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Sample records for salar population-level associations

  1. Confirmation and fine-mapping of a major QTL for resistance to infectious pancreatic necrosis in Atlantic salmon (Salmo salar: population-level associations between markers and trait

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    Moen Thomas

    2009-08-01

    multi-marker haplotypes. One four-marker haplotype was found to be the best predictor of QTL alleles, and was successfully used to deduce genotypes of the underlying polymorphism in 72% of the parents of the next generation within a breeding nucleus. A highly significant population-level correlation was found between deduced alleles at the underlying polymorphism and survival of offspring groups in the fry challenge test, parents with the three deduced genotypes (QQ, Qq, qq having mean offspring mortality rates of 0.13, 0.32, and 0.49, respectively. The frequency of the high-resistance allele (Q in the population was estimated to be 0.30. Apart from this major QTL, one other experiment-wise significant QTL for IPN-resistance was detected, located on linkage group 4. Conclusion The QTL confirmed in this study represents a case of a major gene explaining the bulk of genetic variation for a presumed complex trait. QTL genotypes were deduced within most parents of the 2005 generation of a major breeding company, providing a solid framework for linkage-based MAS within the whole population in subsequent generations. Since haplotype-trait associations valid at the population level were found, there is also a potential for MAS based on linkage disequilibrium (LD. However, in order to use MAS across many generations without reassessment of linkage phases between markers and the underlying polymorphism, the QTL needs to be positioned with even greater accuracy. This will require higher marker densities than are currently available.

  2. Confirmation and fine-mapping of a major QTL for resistance to infectious pancreatic necrosis in Atlantic salmon (Salmo salar): population-level associations between markers and trait

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    Moen, Thomas; Baranski, Matthew; Sonesson, Anna K; Kjøglum, Sissel

    2009-01-01

    . One four-marker haplotype was found to be the best predictor of QTL alleles, and was successfully used to deduce genotypes of the underlying polymorphism in 72% of the parents of the next generation within a breeding nucleus. A highly significant population-level correlation was found between deduced alleles at the underlying polymorphism and survival of offspring groups in the fry challenge test, parents with the three deduced genotypes (QQ, Qq, qq) having mean offspring mortality rates of 0.13, 0.32, and 0.49, respectively. The frequency of the high-resistance allele (Q) in the population was estimated to be 0.30. Apart from this major QTL, one other experiment-wise significant QTL for IPN-resistance was detected, located on linkage group 4. Conclusion The QTL confirmed in this study represents a case of a major gene explaining the bulk of genetic variation for a presumed complex trait. QTL genotypes were deduced within most parents of the 2005 generation of a major breeding company, providing a solid framework for linkage-based MAS within the whole population in subsequent generations. Since haplotype-trait associations valid at the population level were found, there is also a potential for MAS based on linkage disequilibrium (LD). However, in order to use MAS across many generations without reassessment of linkage phases between markers and the underlying polymorphism, the QTL needs to be positioned with even greater accuracy. This will require higher marker densities than are currently available. PMID:19664221

  3. Population levels of wellbeing and the association with social capital.

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    Taylor, A W; Kelly, G; Dal Grande, E; Kelly, D; Marin, T; Hey, N; Burke, K J; Licinio, J

    2017-07-03

    This research investigates wellbeing at the population level across demographic, social and health indicators and assesses the association between wellbeing and social capital. Data from a South Australian monthly chronic disease/risk factor surveillance system of randomly selected adults (mean age 48.7 years; range 16-99) from 2014/5 (n = 5551) were used. Univariable analyses compared wellbeing/social capital indicators, socio-demographic, risk factors and chronic conditions. Multi-nominal logistic regression modelling, adjusting for multiple covariates was used to simultaneously estimate odds ratios for good wellbeing (reference category) versus neither good nor poor, and good wellbeing versus poor wellbeing. 48.6% were male, mean age 48.7 (sd 18.3), 54.3% scored well on all four of the wellbeing indicators, and positive social capital indicators ranged from 93.1% for safety to 50.8% for control over decisions. The higher level of social capital corresponded with the good wellbeing category. Modeling showed higher odds ratios for all social capital variables for the lowest level of wellbeing. These higher odds ratios remained after adjusting for confounders. The relationship between wellbeing, resilience and social capital highlights areas for increased policy focus.

  4. A population-level study of place of death and associated factors in Sweden.

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    Håkanson, Cecilia; Öhlén, Joakim; Morin, Lucas; Cohen, Joachim

    2015-11-01

    The aims of this study were to examine, on a population level, where people die in Sweden, and to investigate associations between place of death and underlying cause of death, socioeconomic and environmental characteristics, with a particular interest in people dying from life-limiting conditions typically in need of palliative care. This population-level study is based on death certificate data for all deceased individuals in Sweden in 2012, with a registered place of death (n=83,712). Multivariable logistic regression was performed to investigate associations between place of death and individual, socioeconomic and environmental characteristics. The results show that, in 2012, 42.1% of all deaths occurred in hospitals, 17.8% occurred at home and 38.1% in nursing home facilities. Individuals dying of conditions indicative of potential palliative care needs were less likely to die in hospital than those dying of other conditions (OR = 0.73; 95% CI = 0.70-0.77). Living at home in urban areas was associated with higher likelihood of dying in hospital or in a nursing home (OR = 1.04 and 1.09 respectively). Educational attainment and marital status were found to be somewhat associated with the place of death. The majority of deaths in Sweden occur in institutional settings, with comparatively larger proportions of nursing home deaths than most countries. Associations between place of death and other variables point to inequalities in availability and/or utilization of health services at the end of life. © 2015 the Nordic Societies of Public Health.

  5. Population-level associations between preschool vulnerability and grade-four basic skills.

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    Amedeo D'Angiulli

    2009-11-01

    Full Text Available This is a predictive validity study examining the extent to which developmental vulnerability at kindergarten entry (as measured by the Early Development Instrument, EDI is associated with children's basic skills in 4th grade (as measured by the Foundation Skills Assessment, FSA.Relative risk analysis was performed on a large database linking individual-level EDI ratings to the scores the same children obtained on a provincial assessment of academic skills (FSA--Foundation Skills Assessment four years later. We found that early vulnerability in kindergarten is associated with the basic skills that underlie populations of children's academic achievement in reading, writing and math, indicating that the Early Development Instrument permits to predict achievement-related skills four years in advance.The EDI can be used to predict children's educational trends at the population level and can help select early prevention and intervention programs targeting pre-school populations at minimum cost.

  6. Population-Level Associations between Preschool Vulnerability and Grade-Four Basic Skills

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    D'Angiulli, Amedeo; Warburton, William; Dahinten, Susan; Hertzman, Clyde

    2009-01-01

    Background This is a predictive validity study examining the extent to which developmental vulnerability at kindergarten entry (as measured by the Early Development Instrument, EDI) is associated with children's basic skills in 4th grade (as measured by the Foundation Skills Assessment, FSA). Methodology/Principal Findings Relative risk analysis was performed on a large database linking individual-level EDI ratings to the scores the same children obtained on a provincial assessment of academic skills (FSA – Foundation Skills Assessment) four years later. We found that early vulnerability in kindergarten is associated with the basic skills that underlie populations of children's academic achievement in reading, writing and math, indicating that the Early Development Instrument permits to predict achievement-related skills four years in advance. Conclusions/Significance The EDI can be used to predict children's educational trends at the population level and can help select early prevention and intervention programs targeting pre-school populations at minimum cost. PMID:19946366

  7. Association of RGS4 variants with schizotypy and cognitive endophenotypes at the population level

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    Smyrnis Nikos

    2008-10-01

    Full Text Available Abstract Background While association studies on schizophrenia show conflicting results regarding the importance of the regulator of the G-protein signaling 4 (RGS4 gene, recent work suggests that RGS4 may impact on the structural and functional integrity of the prefrontal cortex. We aimed to study associations of common RGS4 variants with prefrontal dependent cognitive performance and schizotypy endophenotypes at the population level. Methods Four RGS4 single nucleotide polymorphisms (SNP1 [rs10917670], SNP4 [rs951436], SNP7 [rs951439], and SNP18 [rs2661319] and their haplotypes were selected. Their associations with self-rated schizotypy (SPQ, vigilance, verbal, spatial working memory and antisaccade eye performance were tested with regressions in a representative population of 2,243 young male military conscripts. Results SNP4 was associated with negative schizotypy (higher SPQ negative factor for common T allele, p = 0.009; p = 0.031 for differences across genotypes and a similar trend was seen also for common A allele of SNP18 (p = 0.039 for allele-load model; but p = 0.12 for genotype differences. Haplotype analyses showed a similar pattern with a dose-response for the most common haplotype (GGGG on the negative schizotypy score with or without adjustment for age, IQ and their interaction (p = 0.011 and p = 0.024, respectively. There was no clear evidence for any association of the RGS4 variants with cognitive endophenotypes, except for an isolated effect of SNP18 on antisaccade error rate (p = 0.028 for allele-load model. Conclusion Common RGS4 variants were associated with negative schizotypal personality traits amongst a large cohort of young healthy individuals. In accordance with recent findings, this may suggest that RGS4 variants impact on the functional integrity of the prefrontal cortex, thus increasing susceptibility for psychotic spectrum disorders.

  8. Association between immunisation, reduced weight gain and plasma cortisol concentrations in juvenile Baltic salmon (Salmo salar).

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    Engelbrecht Nielsen, M; Buchmann, K

    1997-01-01

    The changes in plasma cortisol levels, immune response parameters and growth of juvenile Atlantic salmon (Salmo salar) were monitored during a 50 days period following a DNP-HSA (di-nitrophenyl human serum albumin) immunisation program. Antibody titers rose significantly after a single immunisation. An increased plasma cortisol concentration was observed in association with injection of both antigen and saline. A single injection had a significant negative effect on growth of fish and fish subjected to 2 injections with a 25 days interval had an even larger growth reduction. The plasma cortisol concentration and the specific antibody response were compared at an individual level but no correlation was found. Total serum protein increased during the experimental period independently of immunisation. In contrast the total serum immunoglobulin 50 days after the first immunisation was clearly connected to antigen exposure. The observations are discussed in relation to immunophysiological changes during immunisation and stress induction.

  9. Dispersal variability and associated population-level consequences in tree-killing bark beetles.

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    Kautz, Markus; Imron, Muhammad Ali; Dworschak, Kai; Schopf, Reinhard

    2016-01-01

    Dispersal is a key process in the response of insect populations to rapidly changing environmental conditions. Variability among individuals, regarding the timing of dispersal initiation and travelled distance from source, is assumed to contribute to increased population success through risk spreading. However, experiments are often limited in studying complex dispersal interactions over space and time. By applying a local-scaled individual-based simulation model we studied dispersal and emerging infestation patterns in a host - bark beetle system (Picea abies - Ips typgraphus). More specifically, we (i) investigated the effect of individual variability in beetle physiology (flight capacity) and environmental heterogeneity (host susceptibility level) on population-level dispersal success, and (ii) elucidated patterns of spatial and/or temporal variability in individual dispersal success, host selectivity, and the resulting beetle density within colonized hosts in differently susceptible environments. Individual variability in flight capacity of bark beetles causes predominantly positive effects on population-level dispersal success, yet these effects are strongly environment-dependent: Variability is most beneficial in purely resistant habitats, while positive effects are less pronounced in purely susceptible habitats, and largely absent in habitats where host susceptibility is spatially scattered. Despite success rates being highest in purely susceptible habitats, scattered host susceptibility appeared most suitable for dispersing bark beetle populations as it ensures population spread without drastically reducing success rates. At the individual level, dispersal success generally decreases with distance to source and is lowest in early flight cohorts, while host selectivity increased and colonization density decreased with increasing distance across all environments. Our modelling approach is demonstrated to be a powerful tool for studying movement ecology in

  10. Dietary soybean protein concentrate-induced intestinal disorder in marine farmed Atlantic salmon, Salmo salar is associated with alterations in gut microbiota.

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    Green, Timothy J; Smullen, Richard; Barnes, Andrew C

    2013-09-27

    The aquaculture industry has made substantial progress in reducing the fishmeal content of feeds for carnivorous species, driven by demand for improved sustainability and reduced cost. Soybean protein concentrate (SPC) is an attractive replacement for fishmeal, but intestinal disorders have been reported in Atlantic salmon (Salmo salar) fed these diets at high seawater temperatures, with preliminary evidence suggesting SPC induces these disorders by altering the intestinal microbiota. We compared the intestinal microbiota of marine-farmed S. salar fed experimental diets with varying levels of SPC in mid- and late-summer. Terminal restriction fragment length polymorphism (T-RFLP) and 16S rRNA clone library analysis revealed the microbiota adherent to the intestinal tract of salmon is complex at the population level, but simple and highly variable at the individual level. Temporal changes were observed with the bacterial diversity increasing in the intestinal tract in late summer. A Verrucomicrobia was the most frequently observed ribotype in early summer, whilst an Aliivibrio was the most frequently observed ribotype in late summer. Feeding SPC to salmon increased the bacterial diversity of the intestinal tract and resulted in the presence of bacteria not normally associated with marine fish (Escherichia and Propionibacterium). These diet-induced changes to the intestinal-microbiome could be ameliorated by inclusion of a prebiotic (mannan-oligosaccharide or MOS) to the diet. None of the experimental diets induced inflammation of the intestine as assessed by histopathology and expression of inflammatory cytokines. Our results support the "dysbiosis" hypothesis that SPC adversely affects the intestinal microbiota of Atlantic salmon. Crown Copyright © 2013. Published by Elsevier B.V. All rights reserved.

  11. Evolutionary history shapes the association between developmental instability and population-level genetic variation in three-spined sticklebacks.

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    Van Dongen, S; Lens, L; Pape, E; Volckaert, F A M; Raeymaekers, J A M

    2009-08-01

    Developmental instability (DI) is the sensitivity of a developing trait to random noise and can be measured by degrees of directionally random asymmetry [fluctuating asymmetry (FA)]. FA has been shown to increase with loss of genetic variation and inbreeding as measures of genetic stress, but associations vary among studies. Directional selection and evolutionary change of traits have been hypothesized to increase the average levels of FA of these traits and to increase the association strength between FA and population-level genetic variation. We test these two hypotheses in three-spined stickleback (Gasterosteus aculeatus L.) populations that recently colonized the freshwater habitat. Some traits, like lateral bone plates, length of the pelvic spine, frontal gill rakers and eye size, evolved in response to selection regimes during colonization. Other traits, like distal gill rakers and number of pelvic fin rays, did not show such phenotypic shifts. Contrary to a priori predictions, average FA did not systematically increase in traits that were under presumed directional selection, and the increases observed in a few traits were likely to be attributable to other factors. However, traits under directional selection did show a weak but significantly stronger negative association between FA and selectively neutral genetic variation at the population level compared with the traits that did not show an evolutionary change during colonization. These results support our second prediction, providing evidence that selection history can shape associations between DI and population-level genetic variation at neutral markers, which potentially reflect genetic stress. We argue that this might explain at least some of the observed heterogeneities in the patterns of asymmetry.

  12. Associations and dynamics of Vibrionaceae in the environment, from the genus to the population level

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    Alison F Takemura

    2014-02-01

    Full Text Available The Vibrionaceae, which encompasses several potential pathogens, including V. cholerae, the causative agent of cholera, and V. vulnificus, the deadliest seafood-borne pathogen, are a well-studied family of marine bacteria that thrive in a diverse habitats. To elucidate the environmental conditions under which vibrios proliferate, numerous studies have examined correlations with bulk environmental variables – e.g., temperature, salinity, nitrogen and phosphate – and association with potential host organisms. However, how meaningful these environmental associations are remains unclear because data are fragmented across studies with variable sampling and analysis methods. Here, we synthesize findings about Vibrio correlations and physical associations using a framework of increasingly fine environmental and taxonomic scales, to better understand their dynamics in the wild. We first conduct a meta-analysis to determine trends with respect to bulk water environmental variables, and find that while temperature and salinity are generally strongly predictive correlates, other parameters are inconsistent and overall patterns depend on taxonomic resolution. Based on the hypothesis that dynamics may better correlate with more narrowly defined niches, we review evidence for specific association with plants, algae, zooplankton, and animals. We find that Vibrio are attached to many organisms, though evidence for enrichment compared to the water column is often lacking. Additionally, contrary to the notion that they flourish predominantly while attached, Vibrio can have, at least temporarily, a free-living lifestyle and even engage in massive blooms. Fine-scale sampling from the water column has enabled identification of such lifestyle preferences for ecologically cohesive populations, and future efforts will benefit from similar analysis at fine genetic and environmental sampling scales to describe the conditions, habitats, and resources shaping Vibrio

  13. Population-level incidence and risk factors for pulmonary toxicity associated with amiodarone.

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    Jackevicius, Cynthia Anne; Tom, Albert; Essebag, Vidal; Eisenberg, Mark J; Rahme, Elham; Tu, Jack Ven; Humphries, Karin; Behlouli, Hassan; Pilote, Louise

    2011-09-01

    Estimates from clinical trials and small observational studies of the incidence of pulmonary toxicity (PT) associated with amiodarone range from 1% to 10%. We report a unique study of the population-based incidence and potential predictors of PT in a real-world atrial fibrillation (AF) population. We conducted a retrospective cohort study of patients ≥65 years old discharged with AF using linked administrative databases from Quebec, Canada from 1999 to 2007. "Users" and "nonusers" of amiodarone were identified by prescriptions dispensed within 7 days after hospital discharge. PT was defined through International Classification of Diseases, Ninth Revision and Tenth Revision codes for pulmonary fibrosis, alveolar/interstitial lung disease, and adult respiratory distress syndrome. Potential risk factors for PT were identified using multivariable Cox regression. PT occurred in 250 of 6,460 amiodarone users (3.87%) and 676 of 50,993 nonusers (1.33%). Age-standardized PT incidences were 28.30 and 16.02 per 1,000 person-years in men and women users, respectively, and 14.05 and 8.82 per 1,000 person-years in nonusers, respectively. It was associated with amiodarone exposure at all doses (≤200 mg/day, hazard ratio 1.62, 1.35 to 1.96; >200 mg/day, 1.46, 1.22 to 1.75). Other predictors of PT included increasing age (1.01 per year, 1.00 to 1.02), male gender (1.37, 1.19 to 1.57), chronic obstructive pulmonary disease (2.53, 2.21 to 2.89), and renal disease (1.26, 1.06 to 1.50). In conclusion, the population-based incidence of amiodarone PT is in the lower range of what has been previously reported. However, patients with AF who use amiodarone have an approximately 50% higher risk of PT than nonusers. Clinicians may be able to use the present results to identify patients at higher risk for PT and implement strategies to increase monitoring or select alternative therapy. Copyright © 2011 Elsevier Inc. All rights reserved.

  14. Diseases of farmed Atlantic salmon Salmo salar associated with infections by the microsporidian Paranucleospora theridion.

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    Nylund, S; Andersen, L; Saevareid, I; Plarre, H; Watanabe, K; Arnesen, C E; Karlsbakk, E; Nylund, A

    2011-03-16

    The microsporidian Paranucleospora theridion was discovered in Atlantic salmon Salmo salar suffering from proliferative gill disease in a marine farm in western Norway in 2008. The parasite develops in cells of the reticuloendothelial system, cells important for normal immune function. The aim of this study was to see if P. theridion could play a part in some of the diseases with unclear causes in salmon production in Norway, i.e. proliferative gill disease (PGI), pancreas disease (PD), heart and skeletal muscle inflammation (HSMI) and cardiomyopathy syndrome (CMS). P. theridion was present in all areas with salmon farming in Norway, but high prevalence and densities of the parasite in salmon and salmon lice were only seen in southern Norway. This region is also the main area for PGI and PD in Norway. Quantification of pathogens associated with PGI, PD, HSMI and CMS diagnoses showed that P. theridion levels are high in southern Norway, and may therefore play a role in susceptibility and disease development. However, among the different diagnoses, fish with PGI are particularly heavily infected with P. theridion. Therefore, P. theridion appears as a possible primary agent in cases with high mortality in connection with PGI in western Norway.

  15. Diseases of farmed Atlantic salmon Salmo salar associated with infections by the microsporidian Paranucleospora theridion

    OpenAIRE

    Nylund, Stian; Andersen, Linda; Sævareid, I.; Plarre, Heidrun; Watanabe, Kuninori; Arnesen, Carl E.; Karlsbakk, Egil; Nylund, Are

    2011-01-01

    The microsporidian Paranucleospora theridion was discovered in Atlantic salmon Salmo salar suffering from proliferative gill disease in a marine farm in western Norway in 2008. The parasite develops in cells of the reticuloendothelial system, cells important for normal immune function. The aim of this study was to see if P. theridion could play a part in some of the diseases with unclear causes in salmon production in Norway, i.e. proliferative gill disease (PGI), pancreas disease...

  16. Population-level diversity in the association of genetic polymorphisms of one-carbon metabolism with breast cancer risk.

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    Naushad, Shaik Mohammad; Divya, Chandrasekhar; Janaki Ramaiah, M; Hussain, Tajamul; Alrokayan, Salman A; Kutala, Vijay Kumar

    2016-10-01

    variations are the likely risk modulators that are contributing toward ethnic- and population-level variations in genetic associations.

  17. Microbial characterization of microbial ecosystems associated to evaporites domes of gypsum in Salar de Llamara in Atacama desert.

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    Rasuk, Maria Cecilia; Kurth, Daniel; Flores, Maria Regina; Contreras, Manuel; Novoa, Fernando; Poire, Daniel; Farias, Maria Eugenia

    2014-10-01

    The Central Andes in northern Chile contains a large number of closed basins whose central depression is occupied by saline lakes and salt crusts (salars). One of these basins is Salar de Llamara (850 m a.s.l.), where large domed structures of seemingly evaporitic origin forming domes can be found. In this work, we performed a detailed microbial characterization of these domes. Mineralogical studies revealed gypsum (CaSO(4)) as a major component. Microbial communities associated to these structures were analysed by 454 16S rDNA amplicon sequencing and compared between winter and summer seasons. Bacteroidetes Proteobacteria and Planctomycetes remained as the main phylogenetic groups, an increased diversity was found in winter. Comparison of the upper air-exposed part and the lower water-submerged part of the domes in both seasons showed little variation in the upper zone, showing a predominance of Chromatiales (Gammaproteobacteria), Rhodospirillales (Alphaproteobacteria), and Sphingobacteriales (Bacteroidetes). However, the submerged part showed marked differences between seasons, being dominated by Proteobacteria (Alpha and Gamma) and Verrucomicrobia in summer, but with more diverse phyla found in winter. Even though not abundant by sequence, Cyanobacteria were visually identified by scanning electron microscopy (SEM), which also revealed the presence of diatoms. Photosynthetic pigments were detected by high-performance liquid chromatography, being more diverse on the upper photosynthetic layer. Finally, the system was compared with other endoevaporite, mats microbialite and Stromatolites microbial ecosystems, showing higher similitude with evaporitic ecosystems from Atacama and Guerrero Negro. This environment is of special interest for extremophile studies because microbial life develops associated to minerals in the driest desert all over the world. Nevertheless, it is endangered by mining activity associated to copper and lithium extraction; thus, its

  18. Indicator 1.08. Population levels of selected representative forest-associated species to describe genetic diversity

    Science.gov (United States)

    C. H. Sieg; S. M. Owen; C. H. Flather

    2011-01-01

    This indicator uses population trends of selected bird and tree species as a surrogate measure of genetic diversity. Population decreases, especially associated with small populations, can lead to decreases in genetic diversity, and contribute to increased risk of extinction. Many forest-associated species rely on some particular forest structure, vegetation...

  19. Evolutionary history shapes the association between developmental instability and population-level genetic variation in three-spined sticklebacks

    OpenAIRE

    van Dongen, S.; Lens, L.; Pape, E.; Volckaert, Filip; Raeymaekers, Joost

    2009-01-01

    Developmental instability (DI) is the sensitivity of a developing trait to random noise and can be measured by degrees of directionally random asymmetry [fluctuating asymmetry (FA)]. FA has been shown to increase with loss of genetic variation and inbreeding as measures of genetic stress, but associations vary among studies. Directional selection and evolutionary change of traits have been hypothesized to increase the average levels of FA of these traits and to increase the association streng...

  20. Association Between Diabetes During Pregnancy and Peripartum Cardiomyopathy: A Population-Level Analysis of 309,825 Women.

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    Dhesi, Sumandeep; Savu, Anamaria; Ezekowitz, Justin A; Kaul, Padma

    2017-07-01

    Peripartum cardiomyopathy (PPCM) is a form of heart failure associated with pregnancy. The objectives of our study were to determine the incidence and outcomes (maternal and neonatal) of PPCM and its association with diabetes mellitus (DM) in a contemporary population-based cohort. The cohort consisted of 309,825 women with a birth of at least 1 live newborn between January 01, 2005 and September 30, 2014, resulting in 469,150 birth events and 477,089 live newborns. A modified PPCM definition was used, allowing from 32 weeks' gestation and up to 6 months postpartum. Women were categorized according to DM status. A total of 194 PPCM birth events were identified, for an incidence rate of 1/2418 births. Women with PPCM were older, often primiparous, and more likely to have multiple gestations, pre-existing DM, and hypertensive disorders of pregnancy. Although the overall numbers were low, the incidence of PPCM was higher in pregnancies in women with pre-existing DM (1/613 birth events) and gestational DM (1/1751 birth events) vs those with neither (1/2550 birth events). Over a mean follow-up of 3.9 years, the mortality rate was higher in women affected by PPCM than in those who were not, with few deaths overall. Neonatal death was uncommon in the entire cohort but was numerically greater in the PPCM group. The incidence of PPCM in Alberta, Canada was approximately 1/2400 births and was modulated by the presence of DM in pregnancy. The relationship between DM status and PPCM may be confounded by other vascular risk factors, including hypertensive disorders of pregnancy. There were few maternal or neonatal deaths in the overall cohort, but they were numerically higher in the PPCM group. Copyright © 2017 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.

  1. The short-term association of temperature and rainfall with mortality in Vadu Health and Demographic Surveillance System: a population level time series analysis

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    Veena Muralidharan

    2012-11-01

    Full Text Available Background: Research in mainly developed countries has shown that some changes in weather are associated with increased mortality. However, due to the lack of accessible data, few studies have examined such effects of weather on mortality, particularly in rural regions in developing countries. Objective: In this study, we aimed to investigate the relationship between temperature and rainfall with daily mortality in rural India. Design: Daily mortality data were obtained from the Health and Demographic Surveillance System (HDSS in Vadu, India. Daily mean temperature and rainfall data were obtained from a regional meteorological center, India Meteorological Department (IMD, Pune. A Poisson regression model was established over the study period (January 2003–May 2010 to assess the short-term relationship between weather variables and total mortality, adjusting for time trends and stratifying by both age and sex. Result: Mortality was found to be significantly associated with daily ambient temperatures and rainfall, after controlling for seasonality and long-term time trends. Children aged 5 years or below appear particularly susceptible to the effects of warm and cold temperatures and heavy rainfall. The population aged 20–59 years appeared to face increased mortality on hot days. Most age groups were found to have increased mortality rates 7–13 days after rainfall events. This association was particularly evident in women. Conclusion: We found the level of mortality in Vadu HDSS in rural India to be highly affected by both high and low temperatures and rainfall events, with time lags of up to 2 weeks. These results suggest that weather-related mortality may be a public health problem in rural India today. Furthermore, as changes in local climate occur, adaptation measures should be considered to mitigate the potentially negative impacts on public health in these rural communities.

  2. Smoke-Free Workplaces Are Associated with Protection from Second-Hand Smoke at Homes in Nigeria: Evidence for Population-Level Decisions

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    Dorota Kaleta

    2015-01-01

    Full Text Available The evidence suggests that smoke-free workplace policies may change social norms towards exposing others to second-hand smoke at home. The aim of the study was to assess whether being employed in a smoke-free workplace (SFWP is associated with living in a smoke-free home (SFH. We used the data from the Global Adult Tobacco Survey conducted in Nigeria in 2012, in which 9,765 individuals were interviewed including 1,856 persons who worked indoors. The percentage of Nigerians employed in SFWP that reported living in a SFH was higher compared to those employed in a workplace where smoking occurred (95% versus 73%. Working in a SFWP was associated with a significantly higher likelihood of living in a SFH (OR = 5.3; p<0.001. Urban inhabitants indicated more frequently that they lived in SFH compared to rural residents (OR = 2.0; p=0.006. The odds of living in a SFH were significantly higher among nonsmokers and nonsmokeless tobacco users compared to smokers and smokeless tobacco users (OR = 28.8; p<0.001; OR = 7.0; p<0.001. These findings support the need for implementation of comprehensive smoke-free policies in Nigeria that result in substantial health benefits.

  3. How Does Neighborhood Quality Moderate the Association Between Online Video Game Play and Depression? A Population-Level Analysis of Korean Students.

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    Kim, Harris Hyun-Soo; Ahn, Sun Joo Grace

    2016-10-01

    The main objective of our study is to assess the relationship between playing online video games and mental wellbeing of adolescents based on a nationally representative sample. Data come from the Korean Children and Youth Panel Survey (KCYPS), a government-funded multiyear research project. Through a secondary analysis of W2 and W3 of data collected in 2011 and 2012, we examine the extent to which time spent playing online games is related to depression, as measured by a battery of items modeled after the abridged version of Center for Epidemiologic Studies Depression Scale Revised (CESD-R). For proper temporal ordering, the outcome variable is drawn from the latter wave (W3), whereas all time-lagged covariates are taken from the earlier wave (W2). Multilevel regression models show that more game playing is associated with greater depression. Findings also indicate that, net of individual-level variables (e.g., gender, health, family background), living in a community with more divorced families adds to adolescent depression. Finally, a cross-level interaction is observed: the positive association between game playing and depression is more pronounced in an area characterized by a lower aggregate divorce rate.

  4. Clinical, demographic and functional characteristics associated with pharmacotherapy for heart failure in older home care clients: a retrospective, population-level, cross-sectional study.

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    Foebel, Andrea D; Heckman, George A; Hirdes, John P; Tyas, Suzanne L; Tjam, Erin Y; McKelvie, Robert S; Maxwell, Colleen J

    2011-07-01

    Use of combination pharmacotherapy, including angiotensin-converting enzyme (ACE) inhibitors, angiotensin II type 1 receptor antagonists (angiotensin receptor blockers) and β-adrenoceptor antagonists (β-blockers) in the management of heart failure (HF) can reduce mortality, prevent functional decline and reduce health service use. However, these first-line therapies are underused in older populations. This article describes the use and predictors of use of first-line HF therapies in a population-based cohort of older home care clients in Ontario, Canada. To examine the use and correlates of first-line pharmacotherapy in older home care clients with HF. This was a retrospective, cross-sectional study of Resident Assessment Instrument - Home Care (RAI-HC) data in individuals aged ≥65 years receiving home care services in the province of Ontario, Canada. Data collected were from all 14 health regions in Ontario. Home care clients with HF were identified from among those aged ≥65 years whose first RAI-HC assessment occurred between January 2004 and December 2007 (n = 176 866). Potential correlates of pharmacotherapy for HF were identified from the RAI-HC and examined using multivariable logistic regression. HF prevalence was 12.4%. Among clients with HF, 28.6% received no first-line pharmacotherapy; this proportion declined by 6% over the 4 years studied. Only 28.0% were receiving recommended combination therapy. First-line pharmacotherapy use was dependent on hypertension and diabetes mellitus status. Use of pharmacotherapy was less likely among older clients and those with functional impairment, airway disease or behavioural symptoms. Approximately 29% of older home care clients with HF received no first-line HF pharmacotherapy, while another 28% received optimal first-line HF pharmacotherapy. In addition to the expected clinical correlates, the increased likelihood of non-use associated with clients' demographic and functional characteristics raises

  5. First detection, isolation and molecular characterization of infectious salmon anaemia virus associated with clinical disease in farmed Atlantic salmon (Salmo salar) in Chile

    Science.gov (United States)

    Godoy, Marcos G; Aedo, Alejandra; Kibenge, Molly JT; Groman, David B; Yason, Carmencita V; Grothusen, Horts; Lisperguer, Angelica; Calbucura, Marlene; Avendaño, Fernando; Imilán, Marcelo; Jarpa, Miguel; Kibenge, Frederick SB

    2008-01-01

    Background Infectious salmon anaemia (ISA) is a viral disease of marine-farmed Atlantic salmon (Salmo salar) caused by ISA virus (ISAV), which belongs to the genus Isavirus, family Orthomyxoviridae. The virus is considered to be carried by marine wild fish and for over 25 years has caused major disease outbreaks in marine-farmed Atlantic salmon in the Northern hemisphere. In the Southern hemisphere, ISAV was first detected in Chile in 1999 in marine-farmed Coho salmon (Oncorhynchus kisutch). In contrast to the classical presentation of ISA in Atlantic salmon, the presence of ISAV in Chile until now has only been associated with a clinical condition called Icterus Syndrome in Coho salmon and virus isolation has not always been possible. During the winter of 2007, unexplained mortalities were registered in market-size Atlantic salmon in a grow-out site located in Chiloé in Region X of Chile. We report here the diagnostic findings of the first significant clinical outbreak of ISA in marine-farmed Atlantic salmon in Chile and the first characterization of the ISAV isolated from the affected fish. Results In mid-June 2007, an Atlantic salmon marine farm site located in central Chiloé Island in Region X of Chile registered a sudden increase in mortality following recovery from an outbreak of Pisciricketsiosis, which rose to a cumulative mortality of 13.6% by harvest time. Based on the clinical signs and lesions in the affected fish, and laboratory tests performed on the fish tissues, a confirmatory diagnosis of ISA was made; the first time ISA in its classical presentation and for the first time affecting farmed Atlantic salmon in Chile. Rapid sequencing of the virus-specific RT-PCR products amplified from the fish tissues identified the virus to belong to the European genotype (Genotype I) of the highly polymorphic region (HPR) group HPR 7b, but with an 11-amino acid insert in the fusion glycoprotein, and ability to cause cytopathic effects (CPE) in CHSE-214 cell line

  6. First detection, isolation and molecular characterization of infectious salmon anaemia virus associated with clinical disease in farmed Atlantic salmon (Salmo salar) in Chile.

    Science.gov (United States)

    Godoy, Marcos G; Aedo, Alejandra; Kibenge, Molly J T; Groman, David B; Yason, Carmencita V; Grothusen, Horts; Lisperguer, Angelica; Calbucura, Marlene; Avendaño, Fernando; Imilán, Marcelo; Jarpa, Miguel; Kibenge, Frederick S B

    2008-08-04

    Infectious salmon anaemia (ISA) is a viral disease of marine-farmed Atlantic salmon (Salmo salar) caused by ISA virus (ISAV), which belongs to the genus Isavirus, family Orthomyxoviridae. The virus is considered to be carried by marine wild fish and for over 25 years has caused major disease outbreaks in marine-farmed Atlantic salmon in the Northern hemisphere. In the Southern hemisphere, ISAV was first detected in Chile in 1999 in marine-farmed Coho salmon (Oncorhynchus kisutch). In contrast to the classical presentation of ISA in Atlantic salmon, the presence of ISAV in Chile until now has only been associated with a clinical condition called Icterus Syndrome in Coho salmon and virus isolation has not always been possible. During the winter of 2007, unexplained mortalities were registered in market-size Atlantic salmon in a grow-out site located in Chiloé in Region X of Chile. We report here the diagnostic findings of the first significant clinical outbreak of ISA in marine-farmed Atlantic salmon in Chile and the first characterization of the ISAV isolated from the affected fish. In mid-June 2007, an Atlantic salmon marine farm site located in central Chiloé Island in Region X of Chile registered a sudden increase in mortality following recovery from an outbreak of Pisciricketsiosis, which rose to a cumulative mortality of 13.6% by harvest time. Based on the clinical signs and lesions in the affected fish, and laboratory tests performed on the fish tissues, a confirmatory diagnosis of ISA was made; the first time ISA in its classical presentation and for the first time affecting farmed Atlantic salmon in Chile. Rapid sequencing of the virus-specific RT-PCR products amplified from the fish tissues identified the virus to belong to the European genotype (Genotype I) of the highly polymorphic region (HPR) group HPR 7b, but with an 11-amino acid insert in the fusion glycoprotein, and ability to cause cytopathic effects (CPE) in CHSE-214 cell line, characteristics

  7. Genomic Organization and Evolution of the Trace Amine-Associated Receptor (TAAR) Repertoire in Atlantic Salmon (Salmo salar)

    Science.gov (United States)

    Tessarolo, Jordan A.; Tabesh, Mohammad J.; Nesbitt, Michael; Davidson, William S.

    2014-01-01

    There is strong evidence that olfaction plays a key role in the homing of salmonids to their natal spawning grounds, particularly in the freshwater phase. However, the physiological and genetic mechanisms behind this biological phenomenon are largely unknown. It has been shown that Pacific salmon respond to dissolved free amino acids from their natal streams. This indicates that amino acids comprise part of the olfcatory cues for imprinting and homing in salmonids. As trace amine-associated receptors (TAARs), a class of olfactory receptors that are close relatives of the G protein-coupled aminergic neurotransmitter receptors, recognize amino acid metabolites, we hypothesize that TAARs play an important role in salmon homing by recognizing olfactory cues. Therefore, to better understand homing in Atlantic salmon, we set out to characterize the TAAR genes in this species. We searched the first assembly of the Atlantic salmon genome for sequences resembling TAARs previously characterized in other teleosts. We identified 27 putatively functional TAAR genes and 25 putative TAAR pseudogenes, which cluster primarily on chromosome 21 (Ssa21). Phylogenetic analysis of TAAR amino acid sequences from 15 vertebrate species revealed the TAAR gene family arose after the divergence of jawed and jawless vertebrates. The TAARs group into three classes with salmon possessing class I and class III TAARs. Within each class, evolution is characterized by species-specific gene expansions, which is in contrast to what is observed in other olfactory receptor families (e.g., OlfCs and oras). PMID:24760389

  8. The biogeography of the atlantic salmon (Salmo salar) gut microbiome

    OpenAIRE

    Llewellyn, Martin S.; McGinnity, Philip; Dionne, Melanie; Letourneau, Justine; Thonier, Florian; Carvalho, Gary R.; Creer, Simon; Derome, Nicolas

    2015-01-01

    Although understood in many vertebrate systems, the natural diversity of host-associated microbiota has been little studied in teleosts. For migratory fishes, successful exploitation of multiple habitats may affect and be affected by the composition of the intestinal microbiome. We collected 96 Salmo salar from across the Atlantic encompassing both freshwater and marine phases. Dramatic differences between environmental and gut bacterial communities were observed. Furthermore, community compo...

  9. The biogeography of the atlantic salmon (Salmo salar) gut microbiome.

    Science.gov (United States)

    Llewellyn, Martin S; McGinnity, Philip; Dionne, Melanie; Letourneau, Justine; Thonier, Florian; Carvalho, Gary R; Creer, Simon; Derome, Nicolas

    2016-05-01

    Although understood in many vertebrate systems, the natural diversity of host-associated microbiota has been little studied in teleosts. For migratory fishes, successful exploitation of multiple habitats may affect and be affected by the composition of the intestinal microbiome. We collected 96 Salmo salar from across the Atlantic encompassing both freshwater and marine phases. Dramatic differences between environmental and gut bacterial communities were observed. Furthermore, community composition was not significantly impacted by geography. Instead life-cycle stage strongly defined both the diversity and identity of microbial assemblages in the gut, with evidence for community destabilisation in migratory phases. Mycoplasmataceae phylotypes were abundantly recovered in all life-cycle stages. Patterns of Mycoplasmataceae phylotype recruitment to the intestinal microbial community among sites and life-cycle stages support a dual role for deterministic and stochastic processes in defining the composition of the S. salar gut microbiome.

  10. Salt reduction strategy at population level

    Directory of Open Access Journals (Sweden)

    Madhavi Bhargava

    2017-01-01

    Full Text Available World is facing a huge burden of noncommunicable diseases such as hypertension, ischemic health diseases, and stroke. Moreover, the developing countries have had a relatively speedy rise of the problem, with noncommunicable diseases occurring at much lower age as compared to the developed world. The World Health Organization, therefore, recommends reduction in salt intake at population level to <5 g/day. Not all researchers and public health physicians agree to it, leading to conflicting information for a primary care physician. This evidence based summary documents this polarization of the recommendations regarding salt reduction and acknowledges the ongoing challenge primary care physicians face when following such evidence based guidelines.

  11. Estimation of Potential Population Level Effects of Contaminants on Wildlife

    Energy Technology Data Exchange (ETDEWEB)

    Loar, J.M.

    2001-06-11

    The objective of this project is to provide DOE with improved methods to assess risks from contaminants to wildlife populations. The current approach for wildlife risk assessment consists of comparison of contaminant exposure estimates for individual animals to literature-derived toxicity test endpoints. These test endpoints are assumed to estimate thresholds for population-level effects. Moreover, species sensitivities to contaminants is one of several criteria to be considered when selecting assessment endpoints (EPA 1997 and 1998), yet data on the sensitivities of many birds and mammals are lacking. The uncertainties associated with this approach are considerable. First, because toxicity data are not available for most potential wildlife endpoint species, extrapolation of toxicity data from test species to the species of interest is required. There is no consensus on the most appropriate extrapolation method. Second, toxicity data are represented as statistical measures (e.g., NOAEL s or LOAELs) that provide no information on the nature or magnitude of effects. The level of effect is an artifact of the replication and dosing regime employed, and does not indicate how effects might increase with increasing exposure. Consequently, slight exceedance of a LOAEL is not distinguished from greatly exceeding it. Third, the relationship of toxic effects on individuals to effects on populations is poorly estimated by existing methods. It is assumed that if the exposure of individuals exceeds levels associated with impaired reproduction, then population level effects are likely. Uncertainty associated with this assumption is large because depending on the reproductive strategy of a given species, comparable levels of reproductive impairment may result in dramatically different population-level responses. This project included several tasks to address these problems: (1) investigation of the validity of the current allometric scaling approach for interspecies extrapolation

  12. Hydrogeology of the lacustrine system of the eastern margin of the Salar the Atacama (Chile); Hidrogeologia del sistema lagunar del margen este del Salar de Atacama (Chile)

    Energy Technology Data Exchange (ETDEWEB)

    Salas, J.; Guimera, J.; Cornella, O.; Aravena, R.; Guzman, E.; Tore, C.; von Igel, W.; Moreno, R.

    2010-07-01

    A hydrogeological conceptual model of the Eastern margin of the Salar de Atacama (Chile) is proposed taking into account climatic, geological, geomorphological, piezometric, chemical and isotopic data. The study establishes the processes that explain the hydrochemical evolution of waters from salty groundwater in the alluvial aquifer located in eastern part of basin until brines at the saline aquifer of the Salar. The main processes associated with this hydrochemical evolution are evaporation and mixing, but water-crust interaction in the discharge areas of the alluvial aquifer associated with the saline wedge also modifies groundwater composition, and plays a role in the dynamics of the evaporitic crusts in the Salar. The existence of low permeability materials near the surface explains the existence of the permanent surface water bodies in the study area. Based on the data collected in the study three different mechanisms are proposed regarding the main sources of water to the lagoons: (1) discharge of saline groundwater from the detrital and volcanic aquifers of the E margin, (2) discharge of surface waters associated to the N area (Burro Muerto channel), and (3) a combination of both previous mechanisms. (Author).

  13. A SNP in the 5′ flanking region of the myostatin-1b gene is associated with harvest traits in Atlantic salmon (Salmo salar)

    Science.gov (United States)

    2013-01-01

    Background Myostatin (MSTN) belongs to the transforming growth factor-β superfamily and is a potent negative regulator of skeletal muscle development and growth in mammals. Most teleost fish possess two MSTN paralogues. However, as a consequence of a recent whole genome-duplication event, salmonids have four: MSTN-1 (−1a and -1b) and MSTN-2 (−2a and -2b). Evidence suggests that teleost MSTN plays a role in the regulation of muscle growth. In the current study, the MSTN-1b gene was re-sequenced and screened for SNP markers in a commercial population of Atlantic salmon. After genotyping 4,800 progeny for the discovered SNPs, we investigated their association with eight harvest traits - four body-weight traits, two ratios of weight traits, flesh colour and fat percentage - using a mixed model association analysis. Results Three novel SNPs were discovered in the MSTN-1b gene of Atlantic salmon. One of the SNPs, located within the 5′ flanking region (g.1086C > T), had a significant association with harvest traits (p  T locus. The alleles at g.1086C > T act in an additive manner and explain a small percentage of the genetic variation of these phenotypes. Conclusions The association analysis revealed that g.1086C > T had a significant association with all body-weight traits under study. Although the SNP explains a small percentage of the variance, our results indicate that a variation in the 5′ flanking region of the myostatin gene is associated with the genetic regulation of growth in Atlantic salmon. PMID:24283985

  14. Assessing the effectiveness of peracetic acid to remediate post-vaccination Saprolegnia spp.-associated mortality in Atlantic salmon Salmo salar parr in recirculation aquaculture systems

    Science.gov (United States)

    Disease is a major barrier to aquaculture production worldwide, and within the salmon industry it is responsible for the majority of market supply fluctuation. Ubiquitous oomycetes of the Saprolegnia genus are particularly problematic disease agents, associated with an estimated 10% mortality among ...

  15. The effects of ozonation on select waterborne steroid hormones in recirculation aquaculture systems containing sexually mature Atlantic salmon Salmo salar

    Science.gov (United States)

    A controlled 3-month study was conducted in 6 replicated water recirculation aquaculture systems (RAS) containing a mixture of sexually mature and immature Atlantic salmon Salmo salar to determine whether water ozonation is associated with a reduction in waterborne hormones. Post-smolt Atlantic salm...

  16. Are antipredator behaviours of hatchery Salmo salar juveniles similar to wild juveniles?

    Science.gov (United States)

    Salvanes, A G V

    2017-05-01

    This study explores how antipredator behaviour of juvenile Atlantic salmon Salmo salar developed during conventional hatchery rearing of eggs from wild brood stock, compared with the behaviour of wild-caught juveniles from the same population. Juveniles aged 1+ years were tested in two unfamiliar environments; in one S. salar were presented with simulated predator attacks and in the other they were given the opportunity to explore an open-field arena. No difference was found in their spontaneous escape responses or ventilation rate (reflex responses) after simulated predator attacks. Hatchery-reared juveniles were more risk-prone in their behaviours than wild-caught individuals. Hatchery juveniles stayed less time in association with shelter. In the open-field arena, hatchery juveniles were more active than wild juveniles. Hatchery juveniles were also immobile for less time and spent a shorter amount of time than wild juveniles in the fringe of the open-field arena. Salmo salar size had no effect on the observed behaviour. Overall, this study provides empirical evidence that one generation of hatchery rearing does not change reflex responses associated with threats, whereas antipredator behaviour, typically associated with prior experience, was less developed in hatchery-reared than in wild individuals. © 2017 The Fisheries Society of the British Isles.

  17. Towards a Long-Term Strategy for Voluntary-Based Internal Radiation Contamination Monitoring: A Population-Level Analysis of Monitoring Prevalence and Factors Associated with Monitoring Participation Behavior in Fukushima, Japan.

    Science.gov (United States)

    Nomura, Shuhei; Tsubokura, Masaharu; Ozaki, Akihiko; Murakami, Michio; Hodgson, Susan; Blangiardo, Marta; Nishikawa, Yoshitaka; Morita, Tomohiro; Oikawa, Tomoyoshi

    2017-04-09

    Following Japan's 2011 Fukushima nuclear incident, we assessed voluntary-based monitoring behavior in Minamisoma City-located 10-40 km from the Fukushima nuclear plant-to inform future monitoring strategies. The monitoring in Minamisoma included occasional free of charge internal-radiation-exposure measurements. Out of around 70,000 individuals residing in the city before the incident, a total of 45,788 residents (female: 52.1%) aged ≥21 were evaluated. The monitoring prevalence in 2011-2012 was only 30.2%, and this decreased to 17.9% in 2013-2014. Regression analyses were performed to estimate factors associated with the monitoring prevalence and participation behavior. The results show that, in comparison with the age cohort of 21-30 years, the cohort of 71-80 and ≥81 years demonstrated significantly lower monitoring prevalence; female residents had higher monitoring prevalence than male residents; those who were living in evacuation zones at the time of the incident had higher monitoring prevalence than those who lived outside any of the evacuation zones; for those living outside Fukushima and neighboring Prefectures post-incident monitoring prevalence decreased significantly in 2013-2014. Our findings inform the discussion on the concepts of radiation risk perception and accessibility to monitoring and societal decision-making regarding the maintenance of the monitoring program with low monitoring prevalence. We also stress the possibility that the monitoring can work both to check that internal contamination levels are within acceptable limits, and as a risk communication tool, alleviating individuals' concern and anxiety over radiation contamination.

  18. Sperm traits in farmed and wild Atlantic salmon Salmo salar.

    Science.gov (United States)

    Camarillo-Sepulveda, N; Hamoutene, D; Lush, L; Burt, K; Volkoff, H; Fleming, I A

    2016-02-01

    Differences in sperm metabolism and morphology between wild and non-local farmed Atlantic salmon Salmo salar were assessed by measuring metabolic enzyme activities and length of sperm flagella. No differences were observed between wild and farmed S. salar sperm with regards to cell counts or any of the biochemical variables assessed. Flagella of sperm cells were significantly longer in wild than farmed S. salar; however, this did not result in higher energy levels or different fertilization rates. © 2015 The Fisheries Society of the British Isles.

  19. The effects of sustained aerobic swimming on osmoregulatory pathways in Atlantic salmon Salmo salar smolts.

    Science.gov (United States)

    Esbaugh, A J; Kristensen, T; Takle, H; Grosell, M

    2014-11-01

    Atlantic salmon Salmo salar smolts were exposed to one of the four different aerobic exercise regimens for 10 weeks followed by a 1 week final smoltification period in fresh water and a subsequent eight-day seawater transfer period. Samples of gill and intestinal tissue were taken at each time point and gene expression was used to assess the effects of exercise training on both branchial and intestinal osmoregulatory pathways. Real-time polymerase chain reaction (PCR) analysis revealed that exercise training up-regulated the expression of seawater relevant genes in the gills of S. salar smolts, including Na(+) , K(+) ATPase (nka) subunit α1b, the Na(+) , K(+) , 2 Cl(-) co-transporter (nkcc1) and cftr channel. These findings suggest that aerobic exercise stimulates expression of seawater ion transport pathways that may act to shift the seawater transfer window for S. salar smolts. Aerobic exercise also appeared to stimulate freshwater ion uptake mechanisms probably associated with an osmorespiratory compromise related to increased exercise. No differences were observed in plasma Na(+) and Cl(-) concentrations as a consequence of exercise treatment, but plasma Na(+) was lower during the final smoltification period in all treatments. No effects of exercise were observed for intestinal nkcc2, nor the Mg(2+) transporters slc41a2 and transient receptor protein M7 (trpm7); however, expression of both Mg(2+) transporters was affected by salinity transfer suggesting a dynamic role in Mg(2+) homeostasis in fishes. © 2014 The Fisheries Society of the British Isles.

  20. Exiled by Definition:The Salar of Northwest China

    Directory of Open Access Journals (Sweden)

    David SG Goodman

    2005-03-01

    Full Text Available The reform of state socialism came relatively late to Qinghai Province in the Northwest of the People’s Republic of China. One of Qinghai’s most dynamic groups in the social leadership of reform has been the Salar. The Salar were one of the officially recognized nationalities identified in the People’s Republic of China during the 1950s. A relatively small group of some 100,000 currently live along the upper reaches of the Yellow River, on the borders of Qinghai and Gansu Provinces. The Salar are characterised by their commitment to both Islam and China, and by their belief that they live in permanent exile, though there is considerable uncertainty about their origins. The evidence of recent research in Qinghai suggests the perspective of being Chinese citizens, yet a people in exile, significantly shapes recent Salar social and economic activism.

  1. High dietary fiber intake prevents stroke at a population level.

    Science.gov (United States)

    Casiglia, Edoardo; Tikhonoff, Valérie; Caffi, Sandro; Boschetti, Giovanni; Grasselli, Carla; Saugo, Mario; Giordano, Nunzia; Rapisarda, Valentina; Spinella, Paolo; Palatini, Paolo

    2013-10-01

    This research was aimed at clarifying whether high dietary fiber intake has an impact on incidence and risk of stroke at a population level. In 1647 unselected subjects, dietary fiber intake (DFI) was detected in a 12-year population-based study, using other dietary variables, anagraphics, biometrics, blood pressure, heart rate, blood lipids, glucose, insulin, uricaemia, fibrinogenaemia, erytrosedimentation rate, diabetes, insulin resistance, smoking, pulmonary disease and left ventricular hypertrophy as covariables. In adjusted Cox models, high DFI reduced the risk of stroke. In analysis based on quintiles of fiber intake adjusted for confounders, HR for incidence of stroke was lower when the daily intake of soluble fiber was >25 g or that of insoluble fiber was >47 g. In multivariate analyses, using these values as cut-off of DFI, the risk of stroke was lower in those intaking more that the cut-off of soluble (HR 0.31, 0.17-0.55) or insoluble (HR 0.35, 0.19-0.63) fiber. Incidence of stroke was also lower (-50%, p dietary DFI is inversely and independently associated to incidence and risk of stroke in general population. Copyright © 2012 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.

  2. Electrophysiological Techniques for Sea Lion Population-Level Audiometry

    Science.gov (United States)

    2009-09-30

    Audiometry James J. Finneran Space and Naval Warfare Systems Center Pacific, Biosciences Division, Code 71510, 53560 Hull Street, San Diego, CA...DATES COVERED 00-00-2009 to 00-00-2009 4. TITLE AND SUBTITLE Electrophysiological Techniques For Sea Lion Population-Level Audiometry 5a

  3. Population-level changes to promote cardiovascular health

    NARCIS (Netherlands)

    T. Jorgensen (Torben); S. Capewell (S.); E. Prescott (E.); S. Allender (S.); S. Sans (Susana); T. Zdrojewski (T.); D. de Bacquer (Dirk); J. de Sutter (Johan); O.H. Franco (Oscar); S. Løgstrup (S.); G. Volpe (Giampiero); S. Malyutina; W.M.M. Verschuren (W. M. Monique); D. Vanuzzo (Diego)

    2012-01-01

    textabstractBackground: Cardiovascular diseases (CVD) cause 1.8 million premature (<75 years) death annually in Europe. The majority of these deaths are preventable with the most efficient and cost-effective approach being on the population level. The aim of this position paper is to assist

  4. Individual and population-level responses to ocean acidification.

    Science.gov (United States)

    Harvey, Ben P; McKeown, Niall J; Rastrick, Samuel P S; Bertolini, Camilla; Foggo, Andy; Graham, Helen; Hall-Spencer, Jason M; Milazzo, Marco; Shaw, Paul W; Small, Daniel P; Moore, Pippa J

    2016-01-29

    Ocean acidification is predicted to have detrimental effects on many marine organisms and ecological processes. Despite growing evidence for direct impacts on specific species, few studies have simultaneously considered the effects of ocean acidification on individuals (e.g. consequences for energy budgets and resource partitioning) and population level demographic processes. Here we show that ocean acidification increases energetic demands on gastropods resulting in altered energy allocation, i.e. reduced shell size but increased body mass. When scaled up to the population level, long-term exposure to ocean acidification altered population demography, with evidence of a reduction in the proportion of females in the population and genetic signatures of increased variance in reproductive success among individuals. Such increased variance enhances levels of short-term genetic drift which is predicted to inhibit adaptation. Our study indicates that even against a background of high gene flow, ocean acidification is driving individual- and population-level changes that will impact eco-evolutionary trajectories.

  5. Precariousness and the end of salarization in the informational society

    Directory of Open Access Journals (Sweden)

    Frederick Harry Pitts

    2014-04-01

    Full Text Available In this piece, I will critically reflect upon some of the claims made about precariousness and the end of salarization in the context of an informational society. The main source and target of the critique will be one of the most notable early renderings of the topic, that of Manuel Castells, with additional material from Michael Hardt and Antonio Negri. The account will conclude, following Paolo Virno’s negative rendition of Marx’s thesis of the general intellect, that precariousness does not herald the end of salarization and the traditional capital-labour relation, but rather its reinforcement.

  6. Estrogen therapy offsets thermal impairment of vitellogenesis, but not zonagenesis, in maiden spawning female Atlantic salmon (Salmo salar).

    Science.gov (United States)

    Anderson, Kelli; Pankhurst, Ned; King, Harry; Elizur, Abigail

    2017-01-01

    In female Atlantic salmon (Salmo salar), exposure to warm summer temperatures causes a reduction in plasma 17β-estradiol (E2), which impairs downstream vitellogenesis and zonagenesis, and reduces egg fertility and embryo survival. The aim of the present study was to determine whether E2-treatment could offset thermal impairment of endocrine function and maintain egg quality in maiden (first-time-spawning) S. salar reared at 22 °C. Treatment with E2 at 22 °C stimulated vitellogenin (vtg) gene expression and subsequent protein synthesis which promoted oocyte growth and increased egg size relative to untreated fish at 14 and 22 °C. However, E2-treatment at 22 °C was not associated with an increase in egg fertility and embryo survival relative to untreated fish at 22 °C, despite the positive effects of E2-treatment on vitellogenesis and oocyte growth. As there was no evidence to suggest that the estrogen receptor alpha expression was suppressed by high temperature, this could be due to the lack of stimulation on zonagenesis by E2-treatment observed at high temperature during oocyte development. Our results demonstrate that treatment with E2 is not able to maintain zonagenesis or egg quality in maiden S. salar at high temperature, even when vtg gene expression, protein synthesis and subsequent oocyte growth is promoted. This implies that the mechanisms regulating zonagenesis, but not vitellogenesis are impaired at elevated temperature in female S. salar broodstock, and highlights the remarkable complexity of thermally induced endocrine disruption in fish.

  7. Effects of feed quality and quantity on growth, early maturation and smolt development in hatchery-reared landlocked Atlantic salmon Salmo salar.

    Science.gov (United States)

    Norrgård, J R; Bergman, E; Greenberg, L A; Schmitz, M

    2014-10-01

    The effects of feed quality and quantity on growth, early male parr maturation and development of smolt characteristics were studied in hatchery-reared landlocked Atlantic salmon Salmo salar. The fish were subjected to two levels of feed rations and two levels of lipid content from first feeding until release in May of their second year. Salmo salar fed high rations, regardless of lipid content, grew the most and those fed low lipid feed with low rations grew the least. In addition, fish fed low lipid feed had lower body lipid levels than fish fed high lipid feed. Salmo salar from all treatments showed some reduction in condition factor (K) and lipid levels during their second spring. Smolt status was evaluated using both physiological and morphological variables. These results, based on gill Na(+) , K(+) -ATPase (NKA) enzyme activity, saltwater tolerance challenges and visual assessments, were consistent with each other, showing that S. salar from all treatments, except the treatment in which the fish were fed low rations with low lipid content, exhibited characteristics associated with smolting at 2 years of age. Sexually mature male parr from the high ration, high lipid content treatment were also subjected to saltwater challenge tests, and were found to be unable to regulate plasma sodium levels. The proportion of sexually mature male parr was reduced when the fish were fed low feed rations, but was not affected by the lipid content of the feed. Salmo salar fed low rations with low lipid content exhibited the highest degree of severe fin erosion. © 2014 The Fisheries Society of the British Isles.

  8. Water chemistry and its effects on the physiology and survival of Atlantic salmon Salmo salar smolts

    Science.gov (United States)

    Liebich, T.; McCormick, S.D.; Kircheis, D.; Johnson, K.; Regal, R.; Hrabik, T.

    2011-01-01

    The physiological effects of episodic pH fluctuations on Atlantic salmon Salmo salar smolts in eastern Maine, U.S.A., were investigated. During this study, S. salar smolts were exposed to ambient stream-water chemistry conditions at nine sites in four catchments for 3 and 6 day intervals during the spring S. salar smolt migration period. Plasma chloride, plasma glucose, gill aluminium and gill Na+- and K+-ATPase levels in S. salar smolts were assessed in relation to ambient stream-water chemistry during this migration period. Changes in both plasma chloride and plasma glucose levels of S. salar smolts were strongly correlated with stream pH, and S. salar smolt mortality occurred in one study site with ambient stream pH between 5??6 and 5??8 during the study period. The findings from this study suggest that physiological effects on S. salar smolts are strongly correlated with stream pH and that in rivers and streams with low dissolved organic carbon (DOC) concentrations the threshold for physiological effects and mortality probably occurs at a higher pH and shorter exposure period than in rivers with higher DOC. Additionally, whenever an acidification event in which pH drops below 5??9 coincides with S. salar smolt migration in eastern Maine rivers, there is potential for a significant reduction in plasma ions of S. salar smolts. ?? 2011 The Fisheries Society of the British Isles.

  9. Evaluation of LANDSAT-2 (ERTS) images applied to geologic structures and mineral resources of South America. [Salar de Coposa, Chile and Salar of Uyuni, Bolivia

    Science.gov (United States)

    Carter, W. D. (Principal Investigator); Kowalik, W. S.

    1976-01-01

    The author has identified the following significant results. The Salar of Coposa is located in northern Chile along the frontier with Bolivia. The surface was divided into six general classes of materials. Analysis of LANDSAT image 1243-14001 by use of interactive multispectral computer (Image 100) enabled accurate repetition of these general classes based on reflectance. The Salar of Uyuni is the largest of the South American evaporite deposits. Using image 1243-13595, and parallel piped computer classification of reflectance units, the Salar was divided into nine classes ranging from deep to shallow water, water over salt, salt saturated with water, and several classes of dry salt.

  10. Ethnoarchéologie du salar d'Uyuni: sel et cultures régionales inter salar

    Directory of Open Access Journals (Sweden)

    1985-01-01

    Full Text Available Le sel a toujours été l'une des denrées fondamentalement indispensables à la vie quotidienne des hommes. Abondant dans les hauts plateaux des Andes centrales, il constitue l'une des principales richesses des populations locales. Transporté par caravanes de lamas vers d'autres écozones où il est troqué, littoral pacifique, moyennes et basses vallées orientales, il permet à chaque communauté d'acquérir les matières premières complémentaires nécessaires à sa propre subsistance: maïs, piment, coca ou algues... En Bolivie, les grands salars d'Uyuni et de Coipasa sont les principaux centres d'approvisionnement en sel. Leur exploitation à l'échelle régionale semblerait remonter bien avant la colonisation espagnole? La zone 'inter salar,' comprise entre ces deux grandes salines proches de la frontière chilienne, est la mieux localisée pour essayer de déterminer l'exploitation dont elles ont pu faire l'objet par les diverses cultures régionales anciennes ou plus contemporaines. Cette interrogation est à la base du projet d'ethnoarchéologie commencé sur cette région. Cet article présente les premiers résultats de la prospection archéologique menée du 15 novembre au 15 décembre 1983 dans le cadre de ce programme. Il révèle l'existence de nombreux sites fortifiés ou d'inhumations pré-inca correspondant, dans leur ensemble, à des cultures ou grandes chefferies régionales ou 'señoríos' post-Tiwanaku, pouvant être liés au salar et au commerce du sel? Il met l'accent sur les problèmes soulevés par cette étude, les possibilités d'interprétation que nous pouvons avancer et les orientations souhaitées pour compléter ce projet. Siempre la sal ha sido uno de los productos fundamentalmente necesarios para la vida cotidiana del ser humano. Muy abundante en el altiplano de los Andes centrales, la sal constituye, para las poblaciones locales, una de sus riquezas más valiosas. Cargada y trasladada por caravanas de

  11. Photoperiod control of downstream movements of Atlantic salmon Salmo salar smolts

    Science.gov (United States)

    Zydlewski, Gayle B.; Stich, Daniel S.; McCormick, Stephen D.

    2014-01-01

    This study provides the first direct observations that photoperiod controls the initiation of downstream movement in Atlantic salmon Salmo salar smolts. Under simulated natural day length (LDN) conditions and seasonal increases in temperature, smolts increased their downstream movements five-fold for a period of 1 month in late spring. Under the same conditions, parr did not show changes in downstream movement behaviour. When given a shortened day length (10L:14D) beginning in late winter, smolts did not increase the number of downstream movements. An early increase in day length (16L:8D) in late winter resulted in earlier initiation and termination of downstream movements compared to the LDN group. Physiological status and behaviour were related but not completely coincident: gill Na+/K+-ATPase activity increased in all treatments and thyroid hormone was elevated prior to movement in 16L:8D treatment. The most parsimonious model describing downstream movement of smolts included synergistic effects of photoperiod treatment and temperature, indicating that peak movements occurred at colder temperatures in the 16L:8D treatment than in LDN, and temperature did not influence movement of smolts in the 10L:14D treatment. The complicated interactions of photoperiod and temperature are not surprising since many organisms have evolved to rely on correlations among environmental cues and windows of opportunity to time behaviours associated with life-history transitions. These complicated interactions, however, have serious implications for phenological adjustments and persistence ofS. salar populations in response to climate change.

  12. Circumpolar contaminant concentrations in polar bears (Ursus maritimus) and potential population-level effects.

    Science.gov (United States)

    Nuijten, R J M; Hendriks, A J; Jenssen, B M; Schipper, A M

    2016-11-01

    Polar bears (Ursus maritimus) currently receive much attention in the context of global climate change. However, there are other stressors that might threaten the viability of polar bear populations as well, such as exposure to anthropogenic pollutants. Lipophilic organic compounds bio-accumulate and bio-magnify in the food chain, leading to high concentrations at the level of top-predators. In Arctic wildlife, including the polar bear, various adverse health effects have been related to internal concentrations of commercially used anthropogenic chemicals like PCB and DDT. The extent to which these individual health effects are associated to population-level effects is, however, unknown. In this study we assembled data on adipose tissue concentrations of ∑PCB, ∑DDT, dieldrin and ∑PBDE in individual polar bears from peer-reviewed scientific literature. Data were available for 14 out of the 19 subpopulations. We found that internal concentrations of these contaminants exceed threshold values for adverse individual health effects in several subpopulations. In an exploratory regression analysis we identified a clear negative correlation between polar bear population density and sub-population specific contaminant concentrations in adipose tissue. The results suggest that adverse health effects of contaminants in individual polar bears may scale up to population-level consequences. Our study highlights the need to consider contaminant exposure along with other threats in polar bear population viability analyses. Copyright © 2016 Elsevier Inc. All rights reserved.

  13. Nódulos opalinos en facies marginales del salar Olaroz (Puna Argentina

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    Alonso, R.

    1989-04-01

    Full Text Available This article reports the results of a petrological and geochemical study of silica nodules from Quaternary alluvial fallS of the Olaroz Salar. The nodules are mainly constituted by C-T opal, d. (101 spacing to 4,11 A, implying a high-disorder; this is commonly observed in opa! rocks formed in near surface environments, without burial and heating. The chemical composition of the nodules is anomalous when compared with other typical silica-rocks formed in arid continental closed basin, without any eruptive environments (for instance the Cuenca del Tajo in Spain. The siliceous nodules do not have the characteristics of the silcretes and are not associated to the evaporitic facies of the salar. Their genesis is probably related to contamination of groundwater of the alluvial fan with high-silica thermal water. The C-T opal would thus precipitate by either displacing tbe terrigenous host-rock or replacing previous ulexite nodules.Se realiza un estudio petrológico y geoquímico de los nódulos silíceos que se encuentran incluidos en sedimentos terrígenos cuaternarios de la Cuenca de Olaroz (La Puna, Argentina. Estos nódulos se localizan en abanicos aluviales que aparecen encajados, debido a los cambios en el nivel de base que se produce desde el Pleistoceno a la actualidad, durante la evolución de los cuerpos lacustres a salares. Un estudio mediante DRX revela que son rocas constituidas por ópalo C-T, con un espaciado (101 a 4,11 A, que implica un grado de desorden alto, típico de las rocas silíceas formadas en superficie y que no han sufrido enterramiento ni influencia térmica. Su composición química es anómala si se compara con rocas silíceas continentales formadas en ambiente endorreico y fuera de un marco volcánico (Mioceno de la Cuenca del Tajo. No poseyendo características de silcretas y no estando asociadas a la sedimentación evaporítica de los salares, se considera la influencia de aguas termales. La contaminación local y en

  14. Summary Report: Risk Assessment Forum Technical Workshop on Population-level Ecological Risk Assessment

    Science.gov (United States)

    2008 technical workshop regarding development of additional guidelines or best practices for planning, implementing and interpreting ecological risk assessments that involve population-level assessment endpoints.

  15. Neurotrophin and Trk neurotrophin receptors in the inner ear of Salmo salar and Salmo trutta

    National Research Council Canada - National Science Library

    Catania, S; Germanà, A; Cabo, R; Ochoa‐Erena, F. J; Guerrera, M. C; Hannestad, J; Represa, J; Vega, J. A

    2007-01-01

    .... Thus, in the present study, we used Western‐blot analysis and immunohistochemistry to investigate the expression and cell localization of both NTs and Trk receptors in the inner ear of alevins of Salmo salar and Salmo trutta . Western...

  16. Farmed Atlantic salmon Salmo salar L. parr may reduce early survival of wild fish.

    Science.gov (United States)

    Sundt-Hansen, L; Huisman, J; Skoglund, H; Hindar, K

    2015-06-01

    The study examined the density-mediated effects on growth, survival and dispersal of wild and farmed Atlantic salmon Salmo salar offspring in the period immediately following emergence, using a substitutive design. In small confined stream channels, wild parr coexisting with farmed parr had a significantly poorer survival, than wild parr alone. Density did not affect this relationship. In larger unconfined stream channels, wild parr coexisting with farmed parr entered a downstream trap in higher numbers than wild parr in allopatry. The results suggests that during the earliest life stages, farmed S. salar can outcompete wild S. salar, resulting in a reduced survival of wild S. salar. © 2015 The Fisheries Society of the British Isles.

  17. The impact of the genotype on the prevalence of classical scrapie at population level

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    Ortiz-Pelaez Angel

    2011-02-01

    Full Text Available Abstract Total number and genotypes of animals in holdings selected for the genotype & cull option in the Compulsory Scrapie Flock Scheme (CSFS in Great Britain were extracted from the National Scrapie Plan data warehouse. The association between various genotype-related measures and scrapie prevalence infection was tested using zero-inflated negative binomial models with the counts of positive cases as dependent variable, and country, number of flocks in the scheme, flock size, surveillance source and the following genotype-related measurements: the centered-log ratios (clr oof the 15 genotypes, of the proportions of the 5 alleles at codons 136, 154 and 171, of the proportions of the 5 NSP types, and two flock-susceptibility risk indicators, as explanatory variables. A total of 319341 genotyped animals from 168 holdings were included in the analysis. An increased proportion of the ARR/ARR genotype corresponded to a decrease in the number of scrapie cases. ARR/AHQ, AHQ/VRQ, ARH/VRQ and ARQ/VRQ genotypes, NSP type V, ARH, ARQ, AHQ and VRQ alleles and the low and high-susceptibility risk indicators are all associated with an increase risk in the number of scrapie cases. Regardless the management practices; the increased susceptibility that the non-ARR alleles confer on an individual could be extrapolated at the population level. Increasing prevalence of ARR allele reduces the overall risk of scrapie at population level. At genotype level, the VRQ/VRQ genotype, present a very low frequency in the study population, seems to play a residual effect in the overall risk of scrapie in a flock.

  18. Multiple Stressor Differential Tolerances: Possible Implications at the Population Level.

    Science.gov (United States)

    Venâncio, Cátia; Ribeiro, Rui; Soares, Amadeu; Lopes, Isabel

    2016-01-01

    The probability of the most sensitive genotypes being eliminated from a population due to a contaminant pulse--genetic erosion--is negatively associated to the within-genotype variation. A sensitive genotype with a small phenotypic variation would be more prone to be lost-a critically sensitive genotype. Furthermore, natural populations inhabiting contaminated sites are usually exposed to several pollutants. Such co- or sequential exposure can have severe effects if at least some tolerant clonal lineages surviving one contaminant are sensitive to the others. Such an inverse relationship coupled with a low within-genotype variation potentially enhances genetic erosion. Accordingly, this study evaluated co-tolerance and the occurrence of clonal lineages critically sensitive to 48-hours lethal exposures of copper, zinc, cobalt, and chromium among eight clonal lineages of the cladocerans Daphnia longispina. Median lethal concentrations (LC50) of each metal were found to have the potential to provoke genetic erosion. Pairwise comparisons of LC50, from the eight clonal lineages, revealed neither negative nor positive correlations (r ≤ |0.56|; p ≥ 0.18), but inversely sensitive clonal lineages were found for all pairs of metals. Therefore, besides having the potential to eliminate critically sensitive clonal lineages in a first intermediately lethal pulse, all tested metals may provoke further losses of clonal lineages in an already genetically eroded population.

  19. Long-term hypo-osmoregulatory capacity in downstream migrating Atlantic salmon Salmo salar L. smolts.

    Science.gov (United States)

    Urke, H A; Arnekleiv, J V; Nilsen, T O; Nilssen, K J; Rønning, L; Ulvund, J B; Kristensen, T

    2014-10-01

    The duration of hypo-osmoregulatory capacity in downstream migrating Atlantic salmon Salmo salar L smolts previously stocked as startfed young-of-the year (YOY) parr was tested in the River Dalåa from mid-May to late-June 1999. Hypo-osmoregulatory capacity, measured as plasma osmolality and chloride, was assessed after seawater (SW) challenge tests (168 h, salinity = 35). All S. salar exhibited sufficient hypo-osmoregulatory capacity at the initiation of downstream migration in mid-May. Migrating S. salar smolts caught in mid-May and retained in fresh water displayed no signs of de-smoltification as they maintained hypo-osmoregulatory capacity through June. This indicates a physiological smolt window that lasts a minimum of 6 weeks (330 degree days; D°) for hatchery-produced S. salar smolts stocked as YOY parr. Based on the observed river migration speeds, it can be assumed that the S. salar smolts entered SW 2-4 weeks after initiation of migration in the upper parts of the River Dalåa. Hence, based on smolt migration and SW tolerance, it is suggested that stocking of YOY parr is a viable enhancement strategy in the River Dalåa. © 2014 The Fisheries Society of the British Isles.

  20. Protective oral vaccination against infectious salmon anaemia virus in Salmo salar.

    Science.gov (United States)

    Caruffo, Mario; Maturana, Carlos; Kambalapally, Swetha; Larenas, Julio; Tobar, Jaime A

    2016-07-01

    Infectious salmon anemia (ISA) is a systemic disease caused by an orthomyxovirus, which has a significant economic impact on the production of Atlantic salmon (Salmo salar). Currently, there are several commercial ISA vaccines available, however, those products are applied through injection, causing stress in the fish and leaving them susceptible to infectious diseases due to the injection process and associated handling. In this study, we evaluated an oral vaccine against ISA containing a recombinant viral hemagglutinin-esterase and a fusion protein as antigens. Our findings indicated that oral vaccination is able to protect Atlantic salmon against challenge with a high-virulence Chilean isolate. The oral vaccination was also correlated with the induction of IgM-specific antibodies. On the other hand, the vaccine was unable to modulate expression of the antiviral related gene Mx, showing the importance of the humoral response to the disease survival. This study provides new insights into fish protection and immune response induced by an oral vaccine against ISA, but also promises future development of preventive solutions or validation of the current existing therapies. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. Piscine orthoreovirus (PRV) in red and melanised foci in white muscle of Atlantic salmon (Salmo salar).

    Science.gov (United States)

    Bjørgen, Håvard; Wessel, Øystein; Fjelldal, Per Gunnar; Hansen, Tom; Sveier, Harald; Sæbø, Håkon Rydland; Enger, Katrine Bones; Monsen, Eirik; Kvellestad, Agnar; Rimstad, Espen; Koppang, Erling Olaf

    2015-09-08

    Melanised focal changes (black spots) are common findings in the white skeletal muscle of seawater-farmed Atlantic salmon (Salmo salar). Fillets with melanised focal changes are considered as lower quality and cause large economic losses. It has been suggested that red focal changes (red spots) precede the melanised focal changes. In the present work, we examined different populations of captive and wild salmon for the occurrence of both types of changes, which were investigated for the presence of different viruses by immunohistochemistry and RT-qPCR. The occurrence of red or melanised foci varied significantly between the populations, from none in wild fish control group, low prevalence of small foci in fish kept in in-house tanks, to high prevalence of large foci in farm-raised salmon. Large amounts of Piscine orthoreovirus (PRV) antigen were detected in all foci. No other viruses were detected. Red focal changes contained significantly higher levels of PRV RNA than apparently non-affected areas in white muscle of the same individuals. Some changes displayed a transient form between a red and melanised pathotype, indicating a progression from an acute to a chronic manifestation. We conclude that PRV is associated with the focal pathological changes in the white muscle of farmed Atlantic salmon and is a premise for the development of focal melanised changes.

  2. Prokaryotic diversity and biogeochemical characteristics of benthic microbial ecosystems at La Brava, a hypersaline lake at Salar de Atacama, Chile.

    Directory of Open Access Journals (Sweden)

    Maria Eugenia Farias

    Full Text Available Benthic microbial ecosystems of Laguna La Brava, Salar de Atacama, a high altitude hypersaline lake, were characterized in terms of bacterial and archaeal diversity, biogeochemistry, (including O2 and sulfide depth profiles and mineralogy, and physicochemical characteristics. La Brava is one of several lakes in the Salar de Atacama where microbial communities are growing in extreme conditions, including high salinity, high solar insolation, and high levels of metals such as lithium, arsenic, magnesium, and calcium. Evaporation creates hypersaline conditions in these lakes and mineral precipitation is a characteristic geomicrobiological feature of these benthic ecosystems. In this study, the La Brava non-lithifying microbial mats, microbialites, and rhizome-associated concretions were compared to each other and their diversity was related to their environmental conditions. All the ecosystems revealed an unusual community where Euryarchaeota, Crenarchaeota, Acetothermia, Firmicutes and Planctomycetes were the most abundant groups, and cyanobacteria, typically an important primary producer in microbial mats, were relatively insignificant or absent. This suggests that other microorganisms, and possibly novel pathways unique to this system, are responsible for carbon fixation. Depth profiles of O2 and sulfide showed active production and respiration. The mineralogy composition was calcium carbonate (as aragonite and increased from mats to microbialites and rhizome-associated concretions. Halite was also present. Further analyses were performed on representative microbial mats and microbialites by layer. Different taxonomic compositions were observed in the upper layers, with Archaea dominating the non-lithifying mat, and Planctomycetes the microbialite. The bottom layers were similar, with Euryarchaeota, Crenarchaeota and Planctomycetes as dominant phyla. Sequences related to Cyanobacteria were very scarce. These systems may contain previously

  3. Population-Level Exposure to Particulate Air Pollution during Active Travel: Planning for Low-Exposure, Health-Promoting Cities

    Science.gov (United States)

    Hankey, Steve; Lindsey, Greg; Marshall, Julian D.

    2016-01-01

    Background: Providing infrastructure and land uses to encourage active travel (i.e., bicycling and walking) are promising strategies for designing health-promoting cities. Population-level exposure to air pollution during active travel is understudied. Objectives: Our goals were a) to investigate population-level patterns in exposure during active travel, based on spatial estimates of bicycle traffic, pedestrian traffic, and particulate concentrations; and b) to assess how those exposure patterns are associated with the built environment. Methods: We employed facility–demand models (active travel) and land use regression models (particulate concentrations) to estimate block-level (n = 13,604) exposure during rush-hour (1600–1800 hours) in Minneapolis, Minnesota. We used the model-derived estimates to identify land use patterns and characteristics of the street network that are health promoting. We also assessed how exposure is correlated with indicators of health disparities (e.g., household income, proportion of nonwhite residents). Our work uses population-level rates of active travel (i.e., traffic flows) rather than the probability of walking or biking (i.e., “walkability” or “bikeability”) to assess exposure. Results: Active travel often occurs on high-traffic streets or near activity centers where particulate concentrations are highest (i.e., 20–42% of active travel occurs on blocks with high population-level exposure). Only 2–3% of blocks (3–8% of total active travel) are “sweet spots” (i.e., high active travel, low particulate concentrations); sweet spots are located a) near but slightly removed from the city-center or b) on off-street trails. We identified 1,721 blocks (~ 20% of local roads) where shifting active travel from high-traffic roads to adjacent low-traffic roads would reduce exposure by ~ 15%. Active travel is correlated with population density, land use mix, open space, and retail area; particulate concentrations were

  4. Late Mesozoic to Paleogene stratigraphy of the Salar de Atacama Basin, Antofagasta, Northern Chile: Implications for the tectonic evolution of the Central Andes

    Science.gov (United States)

    Mpodozis, Constantino; Arriagada, César; Basso, Matilde; Roperch, Pierrick; Cobbold, Peter; Reich, Martin

    2005-04-01

    The Salar de Atacama basin, the largest "pre-Andean" basin in Northern Chile, was formed in the early Late Cretaceous as a consequence of the tectonic closure and inversion of the Jurassic-Early Cretaceous Tarapacá back arc basin. Inversion led to uplift of the Cordillera de Domeyko (CD), a thick-skinned basement range bounded by a system of reverse faults and blind thrusts with alternating vergence along strike. The almost 6000-m-thick, upper Cretaceous to lower Paleocene sequences (Purilactis Group) infilling the Salar de Atacama basin reflects rapid local subsidence to the east of the CD. Its oldest outcropping unit (Tonel Formation) comprises more than 1000 m of continental red sandstones and evaporites, which began to accumulate as syntectonic growth strata during the initial stages of CD uplift. Tonel strata are capped by almost 3000 m of sandstones and conglomerates of western provenance, representing the sedimentary response to renewed pulses of tectonic shortening, which were deposited in alluvial fan, fluvial and eolian settings together with minor lacustrine mudstone (Purilactis Formation). These are covered by 500 m of coarse, proximal alluvial fan conglomerates (Barros Arana Formation). The top of the Purilactis Group consists of Maastrichtian-Danian alkaline lava and minor welded tuffs and red beds (Cerro Totola Formation: 70-64 Ma K/Ar) deposited during an interval of tectonic quiescence when the El Molino-Yacoraite Late Cretaceous sea covered large tracts of the nearby Altiplano-Puna domain. Limestones interbedded with the Totola volcanics indicate that this marine incursion advanced westwards to reach the eastern CD slope. CD shortening in the Late Cretaceous was accompanied by volcanism and continental sedimentation in fault bounded basins associated to strike slip along the north Chilean magmatic arc to the west of the CD domain, indicating that oblique plate convergence prevailed during the Late Cretaceous. Oblique convergence seems to have

  5. Ethical issues in using Twitter for population-level depression monitoring: a qualitative study.

    Science.gov (United States)

    Mikal, Jude; Hurst, Samantha; Conway, Mike

    2016-04-14

    Recently, significant research effort has focused on using Twitter (and other social media) to investigate mental health at the population-level. While there has been influential work in developing ethical guidelines for Internet discussion forum-based research in public health, there is currently limited work focused on addressing ethical problems in Twitter-based public health research, and less still that considers these issues from users' own perspectives. In this work, we aim to investigate public attitudes towards utilizing public domain Twitter data for population-level mental health monitoring using a qualitative methodology. The study explores user perspectives in a series of five, 2-h focus group interviews. Following a semi-structured protocol, 26 Twitter users with and without a diagnosed history of depression discussed general Twitter use, along with privacy expectations, and ethical issues in using social media for health monitoring, with a particular focus on mental health monitoring. Transcripts were then transcribed, redacted, and coded using a constant comparative approach. While participants expressed a wide range of opinions, there was an overall trend towards a relatively positive view of using public domain Twitter data as a resource for population level mental health monitoring, provided that results are appropriately aggregated. Results are divided into five sections: (1) a profile of respondents' Twitter use patterns and use variability; (2) users' privacy expectations, including expectations regarding data reach and permanence; (3) attitudes towards social media based population-level health monitoring in general, and attitudes towards mental health monitoring in particular; (4) attitudes towards individual versus population-level health monitoring; and (5) users' own recommendations for the appropriate regulation of population-level mental health monitoring. Focus group data reveal a wide range of attitudes towards the use of public

  6. Quantitative genetics of disease resistance in vaccinated and unvaccinated Atlantic salmon (Salmo salar L.)

    Science.gov (United States)

    Drangsholt, T M K; Gjerde, B; Ødegård, J; Finne-Fridell, F; Evensen, Ø; Bentsen, H B

    2011-01-01

    Furunculosis (Aeromonoas salmonicida) is an important disease in Atlantic salmon (Salmo salar) farming. Vaccination and selective breeding for increased resistance to the disease on the basis of challenge tests of unvaccinated fish are used as complementary prophylactic methods. An important issue is whether genetic predisposition to infection is consistent across vaccinated and unvaccinated fish. Hence, the main objective of this study was to determine the magnitude of the genetic associations (correlations) between resistance to furunculosis in vaccinated and unvaccinated fish, and to estimate the magnitude of the correlation of resistance to furunculosis with resistance to the viral diseases infectious pancreatic necrosis (IPN) and infectious salmon anaemia (ISA). Sub-samples of unvaccinated and vaccinated salmon from 150 full-sib families were subjected to separate cohabitation challenge tests. Substantial genetic variation was found in resistance to furunculosis in both the unvaccinated (heritabilities of 0.51±0.05) and vaccinated (0.39±0.06) fish. However, the genetic correlation between resistance to furunculosis in the two groups was low (0.32±0.13), indicating a weak genetic association between resistance in the two groups. Hence, the current selection strategy on the basis of challenge tests of unvaccinated fish is likely to produce low genetic improvement in resistance to furunculosis under field conditions, where fish are vaccinated with an effective vaccine. Evidence was found of significantly favourable genetic associations of resistance to furunculosis in unvaccinated (but less so for vaccinated) fish with resistance to both IPN and ISA (unvaccinated fish), indicating that vaccination ‘mask' genetic associations between resistance to different diseases. PMID:21559049

  7. Population level of main microbiota and yeast-like Candida fungi in women with vulvovaginal candidiasis

    Directory of Open Access Journals (Sweden)

    N. D. Yakovychuk

    2017-06-01

    Full Text Available Aim - to determine population levels of main microbiota and yeast-like fungi of the genus Candida in healthy women and in women with vulvovaginal candidiasis. Materials and methods. For 10 years we have been surveyed 270 women in reproductive age from 19 to 34 years old with vulvovaginal candidiasis and 73 healthy women. In all patients population level of main microflora and yeast-like fungi of the genus Candida in vulvovaginal content has been determined. The isolation of yeast-like fungi of the genus Candida has been performed by seeding of vulvovaginal content on a solid Saboaraud nutrient medium and on Saboaraud medium with the addition of cycloheximide, relatively with pure culture. "Seedlings test" and identification by species with establishment of population level had been performed in each individual case. Results. Coexistence of representatives of the ecosystem "microorganism - microbiota" and compared the changes of microecology of vulvovaginal content in healthy women and women with vulvovaginal candidiasis were defined. In the study of population level of yeast-like fungi of the genus Candida in vulvovaginal content in women with vulvovaginal candidiasis it was found that the dominant species was C. albicans, of population level of which were different from other species, such as C. guillіermondii by 1.77 %, C. krusei - by 4.82 %, C. glabrata - by 5.78 %, C. kefyr – by 8.19 %, C. tropicalis – by 8,35 %, C. inconspicua and C. zeylanoides by 15.08 %. Thus, in the vulvovaginal content of women with vulvovaginal candidiasis yeast-like fungi of the genus Candida of 8 different taxons were at the population level over 5,00 lg CFU/ml, which can not only persist but they were suspected to be agents of inflammation. The results of the study of population levels of autochtonous obligate and facultative bacteria of vulvovaginal content of women with vulvovaginal candidiasis indicated that the level of Lactobacteria decreased by 67

  8. How do protected landscapes associated with high biodiversity and population levels change?

    Directory of Open Access Journals (Sweden)

    Pablo Cuenca

    Full Text Available Most protected areas (PA try to limit logging of forests by means of restrictions on access and use, especially in areas where local communities coexist with the forests and depend on resources derived from PAs. In such contexts, achieving full or effective protection of the forests is almost impossible. This fact has led to researching beyond PAs boundaries in order to examine large surrounding landscapes with multiple forms of properties and restriction on forests use. The present study assessed the change in forest cover and fragmentation between 1990 and 2014, in addition to the drivers that explain such changes in a landscape with the presence of PAs and high-density population belonging to the Chocó-Darien biodiversity hotspot. Results indicated differences in the extent and spatial patterns of change in forest cover of PAs and their surrounding landscapes. Two PAs exhibited a tendency to increase fragmentation and lose their forests in comparison with the stable protection of the forests in other PAs during this period. However, the greatest change in forest cover and fragmentation was observed in the surrounding landscapes, where the best connection to markets and transport networks were the dominating deforestation drivers. Our findings corroborated that the PAs were a shield against the deforestation of the tropical Andean forest, especially in landscapes with high-density population. However, the fragmentation of the forest cannot be avoided around the PAs limits. It is expected that, if this tendency continues in the future, the biodiversity in the Chocó-Darien hotspot will be seriously affected.

  9. Achieving population-level immunity to rabies in free-roaming dogs in Africa and Asia.

    Directory of Open Access Journals (Sweden)

    Michelle K Morters

    Full Text Available Canine rabies can be effectively controlled by vaccination with readily available, high-quality vaccines. These vaccines should provide protection from challenge in healthy dogs, for the claimed period, for duration of immunity, which is often two or three years. It has been suggested that, in free-roaming dog populations where rabies is endemic, vaccine-induced protection may be compromised by immuno-suppression through malnutrition, infection and other stressors. This may reduce the proportion of dogs that seroconvert to the vaccine during vaccination campaigns and the duration of immunity of those dogs that seroconvert. Vaccination coverage may also be limited through insufficient vaccine delivery during vaccination campaigns and the loss of vaccinated individuals from populations through demographic processes. This is the first longitudinal study to evaluate temporal variations in rabies vaccine-induced serological responses, and factors associated with these variations, at the individual level in previously unvaccinated free-roaming dog populations. Individual-level serological and health-based data were collected from three cohorts of dogs in regions where rabies is endemic, one in South Africa and two in Indonesia. We found that the vast majority of dogs seroconverted to the vaccine; however, there was considerable variation in titres, partly attributable to illness and lactation at the time of vaccination. Furthermore, >70% of the dogs were vaccinated through community engagement and door-to-door vaccine delivery, even in Indonesia where the majority of the dogs needed to be caught by net on successive occasions for repeat blood sampling and vaccination. This demonstrates the feasibility of achieving population-level immunity in free-roaming dog populations in rabies-endemic regions. However, attrition of immune individuals through demographic processes and waning immunity necessitates repeat vaccination of populations within at least

  10. Achieving Population-Level Immunity to Rabies in Free-Roaming Dogs in Africa and Asia

    Science.gov (United States)

    Morters, Michelle K.; McKinley, Trevelyan J.; Horton, Daniel L.; Cleaveland, Sarah; Schoeman, Johan P.; Restif, Olivier; Whay, Helen R.; Goddard, Amelia; Fooks, Anthony R.; Damriyasa, I. Made; Wood, James L. N.

    2014-01-01

    Canine rabies can be effectively controlled by vaccination with readily available, high-quality vaccines. These vaccines should provide protection from challenge in healthy dogs, for the claimed period, for duration of immunity, which is often two or three years. It has been suggested that, in free-roaming dog populations where rabies is endemic, vaccine-induced protection may be compromised by immuno-suppression through malnutrition, infection and other stressors. This may reduce the proportion of dogs that seroconvert to the vaccine during vaccination campaigns and the duration of immunity of those dogs that seroconvert. Vaccination coverage may also be limited through insufficient vaccine delivery during vaccination campaigns and the loss of vaccinated individuals from populations through demographic processes. This is the first longitudinal study to evaluate temporal variations in rabies vaccine-induced serological responses, and factors associated with these variations, at the individual level in previously unvaccinated free-roaming dog populations. Individual-level serological and health-based data were collected from three cohorts of dogs in regions where rabies is endemic, one in South Africa and two in Indonesia. We found that the vast majority of dogs seroconverted to the vaccine; however, there was considerable variation in titres, partly attributable to illness and lactation at the time of vaccination. Furthermore, >70% of the dogs were vaccinated through community engagement and door-to-door vaccine delivery, even in Indonesia where the majority of the dogs needed to be caught by net on successive occasions for repeat blood sampling and vaccination. This demonstrates the feasibility of achieving population-level immunity in free-roaming dog populations in rabies-endemic regions. However, attrition of immune individuals through demographic processes and waning immunity necessitates repeat vaccination of populations within at least two years to ensure

  11. Effects of episodic acidification on Atlantic salmon (Salmo salar) smolts

    Science.gov (United States)

    Magee, J.A.; Obedzinski, M.; McCormick, S.D.; Kocik, J.F.

    2003-01-01

    The effect of episodic acidification on Atlantic salmon (Salmo salar) smolt physiology and survival in fresh water (FW) and seawater (SW) was investigated. Smolts were held in either ambient (control, pH 6.0-6.6), acidified (chronic, pH 4.4-6.1), or episodically acidified (episodic, pH reduction from control levels to pH ???5.2 for 48 h once weekly) river water for 31 days and then transferred to 34??? SW. Smolts fed little while in acidified conditions and chronic smolts did not grow in length or weight. In FW, chronic smolts experienced increases in hematocrit and plasma potassium and reductions in plasma sodium and chloride. Upon transfer to SW, chronic and episodic smolts experienced reductions in hematocrit, increases in plasma sodium, chloride, and potassium levels, and suffered mortalities. Gill Na+,K+-ATPase and citrate synthase activities were reduced by exposure to acid. For most parameters, the effect of episodic acid exposure was less than that of chronic acidification. Exposure to acidic conditions, even when short in duration and followed by a 30-h recovery period in suitable water (pH 6.5), led to a 35% mortality of smolts upon transfer to SW. This study highlights the importance of measuring and assessing sublethal stresses in FW and their ultimate effects in marine ecosystems.

  12. Quality grading of Atlantic salmon (Salmo salar) by computer vision.

    Science.gov (United States)

    Misimi, E; Erikson, U; Skavhaug, A

    2008-06-01

    In this study, we present a promising method of computer vision-based quality grading of whole Atlantic salmon (Salmo salar). Using computer vision, it was possible to differentiate among different quality grades of Atlantic salmon based on the external geometrical information contained in the fish images. Initially, before the image acquisition, the fish were subjectively graded and labeled into grading classes by a qualified human inspector in the processing plant. Prior to classification, the salmon images were segmented into binary images, and then feature extraction was performed on the geometrical parameters of the fish from the grading classes. The classification algorithm was a threshold-based classifier, which was designed using linear discriminant analysis. The performance of the classifier was tested by using the leave-one-out cross-validation method, and the classification results showed a good agreement between the classification done by human inspectors and by the computer vision. The computer vision-based method classified correctly 90% of the salmon from the data set as compared with the classification by human inspector. Overall, it was shown that computer vision can be used as a powerful tool to grade Atlantic salmon into quality grades in a fast and nondestructive manner by a relatively simple classifier algorithm. The low cost of implementation of today's advanced computer vision solutions makes this method feasible for industrial purposes in fish plants as it can replace manual labor, on which grading tasks still rely.

  13. Population-level impact, herd immunity, and elimination after human papillomavirus vaccination

    DEFF Research Database (Denmark)

    Brisson, Marc; Bénard, Élodie; Drolet, Mélanie

    2016-01-01

    BackgroundModelling studies have been widely used to inform human papillomavirus (HPV) vaccination policy decisions; however, many models exist and it is not known whether they produce consistent predictions of population-level effectiveness and herd effects. We did a systematic review and meta-a...

  14. Bioecological Theory, Early Child Development and the Validation of the Population-Level Early Development Instrument

    Science.gov (United States)

    Guhn, Martin; Goelman, Hillel

    2011-01-01

    The Early Development Instrument (EDI; Janus and Offord in "Canadian Journal of Behavioural Science" 39:1-22, 2007) project is a Canadian population-level, longitudinal research project, in which teacher ratings of Kindergarten children's early development and wellbeing are linked to health and academic achievement variables at the…

  15. Unmet Health Care Needs of People with Disabilities: Population Level Evidence

    Science.gov (United States)

    McColl, Mary Ann; Jarzynowska, Anna; Shortt, S. E. D.

    2010-01-01

    The present study examined population level data on unmet needs for adults with physical, sensory and cognitive disabilities, using the National Population Health Survey. The study revealed that disabled adults (aged 20-64) reported more than three times as many unmet health care needs as their non-disabled counterparts. Even after controlling for…

  16. Facultative anadromy in salmonids: linking habitat, individual life history decisions, and population-level consequences

    Science.gov (United States)

    Steven F. Railsback; Bret C. Harvey; Jason L. White

    2014-01-01

    Modeling and management of facultative anadromous salmonids is complicated by their ability to select anadromous or resident life histories. Conventional theory for this behavior assumes individuals select the strategy offering highest expected reproductive success but does not predict how population-level consequences such as a stream’s smolt production emerge from...

  17. Determinants of occupational diseases in the netherlands: risks at the individual and the population level: abstract

    NARCIS (Netherlands)

    Steenbeek, R.; Dam, L. van; Vroome, E. de

    2017-01-01

    Oral presentation Eliminating Occupational Disease: Translating Research into Action, EPICOH 2017, EPICOH 2017, 28–31 August 2017, Edinburgh, UK. Objective To identify the main determinants of occupational diseases at both the individual and the population level. Methods This study used data from

  18. Ecological interactions affecting population-level responses to chemical stress in Mesocyclops leuckarti.

    Science.gov (United States)

    Kulkarni, Devdutt; Hommen, Udo; Schäffer, Andreas; Preuss, Thomas G

    2014-10-01

    Higher tiers of ecological risk assessment (ERA) consider population and community-level endpoints. At the population level, the phenomenon of density dependence is one of the most important ecological processes that influence population dynamics. In this study, we investigated how different mechanisms of density dependence would influence population-level ERA of the cyclopoid copepod Mesocyclops leuckarti under toxicant exposure. We used a combined approach of laboratory experiments and individual-based modelling. An individual-based model was developed for M. leuckarti to simulate population dynamics under triphenyltin exposure based on individual-level ecological and toxicological data from laboratory experiments. The study primarily aimed to-(1) determine which life-cycle processes, based on feeding strategies, are most significant in determining density dependence (2) explore how these mechanisms of density dependence affect extrapolation from individual-level effects to the population level under toxicant exposure. Model simulations showed that cannibalism of nauplii that were already stressed by TPT exposure contributed to synergistic effects of biotic and abiotic factors and led to a twofold stress being exerted on the nauplii, thereby resulting in a higher population vulnerability compared to the scenario without cannibalism. Our results suggest that in population-level risk assessment, it is easy to underestimate toxicity unless underlying ecological interactions including mechanisms of population-level density regulation are considered. This study is an example of how a combined approach of experiments and mechanistic modelling can lead to a thorough understanding of ecological processes in ecotoxicology and enable a more realistic ERA. Copyright © 2014 Elsevier Ltd. All rights reserved.

  19. Sodium-potassium dependent adenosine triphosphatase activity in gills and kidneys of Atlantic salmon (Salmo salar)

    Science.gov (United States)

    McCartney, T.H.

    1976-01-01

    1. Gill and kidney ATPase activities of 2-year-old Atlantic salmon (Salmo salar) were determined periodically from March to July.2. Na-K ATPase activity increased in the gill and declined in the kidney during the time encompassing transformation of parr to smolt under hatchery conditions.

  20. Hormone receptors in gills of smolting Atlantic salmon, Salmo salar

    DEFF Research Database (Denmark)

    Kiilerich, Pia; Kristiansen, Karsten; Madsen, Steffen

    2007-01-01

    This is the first study to report concurrent dynamics in mRNA expression of growth hormone receptor (GHR), prolactin receptor (PRLR), gluco- and mineralocorticoid receptor (GR and MR) and the 11beta-hydroxysteroid dehydrogenase type-2 enzyme (11beta-HSD2) in Atlantic salmon (Salmo salar) gill...

  1. Movements of two strains of radio tagged Atlantic salmon, Salmo salar L., smolts through a reservoir

    DEFF Research Database (Denmark)

    Aarestrup, Kim; Jepsen, Niels; Rasmusssen, Gorm

    1999-01-01

    Smolt migration through a shallow and turbid hydro-reservoir in a major Danish river system was investigated using radiotelemetry. Hatchery-reared 1+-year-old Atlantic salmon, Salmo salar L., smolts of equal size from two different non- native strains were radio-tagged and followed during...

  2. Brief communication: Soybean meal-induced uptake block in Atlantic salmon Salmo salar distal enterocytes

    NARCIS (Netherlands)

    Urán, P.; Aydin, R.; Schrama, J.W.; Verreth, J.A.J.; Rombout, J.H.W.M.

    2008-01-01

    Soybean meal-induced enteritis was characterized by the disappearance of the supranuclear vacuoles (SNV) in the enterocytes of the distal intestine of Atlantic salmon Salmo salar. The loss of SNV was correlated with an endocytosis uptake block as shown with ferritin as a marker molecule.

  3. Population-Level Exposure to Particulate Air Pollution during Active Travel: Planning for Low-Exposure, Health-Promoting Cities.

    Science.gov (United States)

    Hankey, Steve; Lindsey, Greg; Marshall, Julian D

    2017-04-01

    Providing infrastructure and land uses to encourage active travel (i.e., bicycling and walking) are promising strategies for designing health-promoting cities. Population-level exposure to air pollution during active travel is understudied. Our goals were a ) to investigate population-level patterns in exposure during active travel, based on spatial estimates of bicycle traffic, pedestrian traffic, and particulate concentrations; and b ) to assess how those exposure patterns are associated with the built environment. We employed facility-demand models (active travel) and land use regression models (particulate concentrations) to estimate block-level ( n = 13,604) exposure during rush-hour (1600-1800 hours) in Minneapolis, Minnesota. We used the model-derived estimates to identify land use patterns and characteristics of the street network that are health promoting. We also assessed how exposure is correlated with indicators of health disparities (e.g., household income, proportion of nonwhite residents). Our work uses population-level rates of active travel (i.e., traffic flows) rather than the probability of walking or biking (i.e., "walkability" or "bikeability") to assess exposure. Active travel often occurs on high-traffic streets or near activity centers where particulate concentrations are highest (i.e., 20-42% of active travel occurs on blocks with high population-level exposure). Only 2-3% of blocks (3-8% of total active travel) are "sweet spots" (i.e., high active travel, low particulate concentrations); sweet spots are located a ) near but slightly removed from the city-center or b ) on off-street trails. We identified 1,721 blocks (~ 20% of local roads) where shifting active travel from high-traffic roads to adjacent low-traffic roads would reduce exposure by ~ 15%. Active travel is correlated with population density, land use mix, open space, and retail area; particulate concentrations were mostly unchanged with land use. Public health officials and

  4. The impact of escaped farmed Atlantic salmon (Salmo salar L.) on catch statistics in Scotland.

    Science.gov (United States)

    Green, Darren M; Penman, David J; Migaud, Herve; Bron, James E; Taggart, John B; McAndrew, Brendan J

    2012-01-01

    In Scotland and elsewhere, there are concerns that escaped farmed Atlantic salmon (Salmo salar L.) may impact on wild salmon stocks. Potential detrimental effects could arise through disease spread, competition, or inter-breeding. We investigated whether there is evidence of a direct effect of recorded salmon escape events on wild stocks in Scotland using anglers' counts of caught salmon (classified as wild or farmed) and sea trout (Salmo trutta L.). This tests specifically whether documented escape events can be associated with reduced or elevated escapes detected in the catch over a five-year time window, after accounting for overall variation between areas and years. Alternate model frameworks were somewhat inconsistent, however no robust association was found between documented escape events and higher proportion of farm-origin salmon in anglers' catch, nor with overall catch size. A weak positive correlation was found between local escapes and subsequent sea trout catch. This is in the opposite direction to what would be expected if salmon escapes negatively affected wild fish numbers. Our approach specifically investigated documented escape events, contrasting with earlier studies examining potentially wider effects of salmon farming on wild catch size. This approach is more conservative, but alleviates some potential sources of confounding, which are always of concern in observational studies. Successful analysis of anglers' reports of escaped farmed salmon requires high data quality, particularly since reports of farmed salmon are a relatively rare event in the Scottish data. Therefore, as part of our analysis, we reviewed studies of potential sensitivity and specificity of determination of farmed origin. Specificity estimates are generally high in the literature, making an analysis of the form we have performed feasible.

  5. The impact of escaped farmed Atlantic salmon (Salmo salar L. on catch statistics in Scotland.

    Directory of Open Access Journals (Sweden)

    Darren M Green

    Full Text Available In Scotland and elsewhere, there are concerns that escaped farmed Atlantic salmon (Salmo salar L. may impact on wild salmon stocks. Potential detrimental effects could arise through disease spread, competition, or inter-breeding. We investigated whether there is evidence of a direct effect of recorded salmon escape events on wild stocks in Scotland using anglers' counts of caught salmon (classified as wild or farmed and sea trout (Salmo trutta L.. This tests specifically whether documented escape events can be associated with reduced or elevated escapes detected in the catch over a five-year time window, after accounting for overall variation between areas and years. Alternate model frameworks were somewhat inconsistent, however no robust association was found between documented escape events and higher proportion of farm-origin salmon in anglers' catch, nor with overall catch size. A weak positive correlation was found between local escapes and subsequent sea trout catch. This is in the opposite direction to what would be expected if salmon escapes negatively affected wild fish numbers. Our approach specifically investigated documented escape events, contrasting with earlier studies examining potentially wider effects of salmon farming on wild catch size. This approach is more conservative, but alleviates some potential sources of confounding, which are always of concern in observational studies. Successful analysis of anglers' reports of escaped farmed salmon requires high data quality, particularly since reports of farmed salmon are a relatively rare event in the Scottish data. Therefore, as part of our analysis, we reviewed studies of potential sensitivity and specificity of determination of farmed origin. Specificity estimates are generally high in the literature, making an analysis of the form we have performed feasible.

  6. Tackling causes and costs of ED presentation for American football injuries: a population-level study.

    Science.gov (United States)

    Smart, Blair J; Haring, R Sterling; Asemota, Anthony O; Scott, John W; Canner, Joseph K; Nejim, Besma J; George, Benjamin P; Alsulaim, Hatim; Kirsch, Thomas D; Schneider, Eric B

    2016-07-01

    injury type-specific variability. Overall, at the US population, estimated total charges of $771299862 were incurred over the 2-year period. In this nationally representative sample, most ED-treated injuries associated with football were not acutely life threatening and very few required major therapeutic intervention. This study provides a cross-sectional overview of ED presentation for acute football-related injury across age groups at the population level in recent years. Longitudinal studies may be warranted to examine associations between the patterns of injury observed in this study and long-term outcomes among American tackle football players. Copyright © 2016 Elsevier Inc. All rights reserved.

  7. Weight loss and fillet quality characteristics of Atlantic salmon (Salmo salar) after purging for 5, 10, 15 or 20 days

    Science.gov (United States)

    Atlantic salmon, Salmo salar, are typically cultured in marine net pens. However, technological advancements in recirculating aquaculture systems have increased the feasibility of culturing Atlantic salmon in land-based systems to alleviate environmental and disease issues limiting sustainability. ...

  8. The role of ethnicity in predicting diabetes risk at the population level

    Science.gov (United States)

    Rosella, Laura C.; Mustard, Cameron A.; Stukel, Therese A.; Corey, Paul; Hux, Jan; Roos, Les; Manuel, Douglas G.

    2012-01-01

    Background. The current form of the Diabetes Population Risk Tool (DPoRT) includes a non-specific category of ethnicity in concordance with publicly data available. Given the importance of ethnicity in influencing diabetes risk and its significance in a multi-ethnic population, it is prudent to determine its influence on a population-based risk prediction tool. Objective. To apply and compare the DPoRT with a modified version that includes detailed ethnic information in Canada's largest and most ethnically diverse province. Methods. Two additional diabetes prediction models were created: a model that contained predictors specific to the following ethnic groups – White, Black, Asian, south Asian, and First Nation; and a reference model which did not include a term for ethnicity. In addition to discrimination and calibration, 10-year diabetes incidence was compared. The algorithms were developed in Ontario using the 1996–1997 National Population Health Survey (N = 19,861) and validated in the 2000/2001 Canadian Community Health Survey (N = 26,465). Results. All non-white ethnicities were associated with higher risk for developing diabetes with south Asians having the highest risk. Discrimination was similar (0.75–0.77) and sufficient calibration was maintained for all models except the detailed ethnicity models for males. DPoRT produced the lowest overall ratio between observed and predicted diabetes risk. DPoRT identified more high risk cases than the other algorithms in males, whereas in females both DPoRT and the full ethnicity model identified more high risk cases. Overall DPoRT and full ethnicity algorithms were very similar in terms of predictive accuracy and population risk. Conclusion. Although from the individual risk perspective, incorporating information on ethnicity is important, when predicting new cases of diabetes at the population level and accounting for other risk factors, detailed ethnic information did not improve the discrimination and

  9. Population level determinants of acute mountain sickness among young men: a retrospective study

    Directory of Open Access Journals (Sweden)

    You Haiyan

    2011-09-01

    Full Text Available Abstract Background Many visitors, including military troops, who enter highland regions from low altitude areas may suffer from acute mountain sickness (AMS, which negatively impacts workable man-hours and increases healthcare costs. The aim of this study was to evaluate the population level risk factors and build a multivariate model, which might be applicable to reduce the effects of AMS on Chinese young men traveling to this region. Methods Chinese highland military medical records were used to obtain data of young men (n = 3727 who entered the Tibet plateau between the years of 2006-2009. The relationship between AMS and travel profile, demographic characteristics, and health behaviors were evaluated by logistic regression. Univariate logistic models estimated the crude odds ratio. The variables that showed significance in the univariate model were included in a multivariate model to derive adjusted odds ratios and build the final model. Data corresponding to odd and even years (2 subsets were analyzed separately and used in a simple cross-validation. Results Univariate analysis indicated that travel profile, prophylactic use, ethnicity, and province of birth were all associated with AMS in both subsets. In multivariate analysis, young men who traveled from lower altitude (600-800 m vs. 1300-1500 m, adjusted odds ratio (AOR = 1.32-1.44 to higher altitudes (4100-4300 m vs. 2900-3100 m, AOR = 3.94-4.12; 3600-3700 m vs. 2900-3100 m, AOR = 2.71-2.74 by air or rapid land transport for emergency mission deployment (emergency land deployment vs. normal land deployment, AOR = 2.08-2.11; normal air deployment vs. normal land deployment, AOR = 2.00-2.20; emergency air deployment vs. normal land deployment, AOR = 2.40-3.34 during the cold season (cold vs. warm, AOR = 1.25-1.28 are at great risk for developing AMS. Non-Tibetan male soldiers (Tibetan vs. Han, AOR = 0.03-0.08, born and raised in lower provinces (eastern vs. northwestern, AOR = 1

  10. Natural selection constrains personality and brain gene expression differences in Atlantic salmon (Salmo salar).

    Science.gov (United States)

    Thörnqvist, Per-Ove; Höglund, Erik; Winberg, Svante

    2015-04-01

    In stream-spawning salmonid fishes there is a considerable variation in the timing of when fry leave the spawning nests and establish a feeding territory. The timing of emergence from spawning nests appears to be related to behavioural and physiological traits, e.g. early emerging fish are bolder and more aggressive. In the present study, emerging Atlantic salmon (Salmo salar L.) alevins were sorted into three fractions: early, intermediate and late emerging. At the parr stage, behaviour, stress responses, hindbrain monoaminergic activity and forebrain gene expression were explored in fish from the early and late emerging fractions (first and last 25%). The results show that when subjected to confinement stress, fish from the late emerging fraction respond with a larger activation of the brain serotonergic system than fish from the early fraction. Similarly, in late emerging fish, stress resulted in elevated expression of mRNA coding for serotonin 1A receptors (5-HT1A), GABA-A receptor-associated protein and ependymin, effects not observed in fish from the early emerging fraction. Moreover, fish from the early emerging fraction displayed bolder behaviour than their late emerging littermates. Taken together, these results suggest that time of emergence, boldness and aggression are linked to each other, forming a behavioural syndrome in juvenile salmon. Differences in brain gene expression between early and late emerging salmon add further support to a relationship between stress coping style and timing of emergence. However, early and late emerging salmon do not appear to differ in hypothalamus-pituitary-interrenal (HPI) axis reactivity, another characteristic of divergent stress coping styles. © 2015. Published by The Company of Biologists Ltd.

  11. Aerobic training stimulates growth and promotes disease resistance in Atlantic salmon (Salmo salar).

    Science.gov (United States)

    Castro, Vicente; Grisdale-Helland, Barbara; Helland, Ståle J; Kristensen, Torstein; Jørgensen, Sven Martin; Helgerud, Jan; Claireaux, Guy; Farrell, Anthony P; Krasnov, Aleksei; Takle, Harald

    2011-10-01

    Improving fish robustness is of utmost relevance to reducing fish losses in farming. Although not previously examined, we hypothesized that aerobic training, as shown for human studies, could strengthen disease resistance in Atlantic salmon (Salmo salar). Thus, we exercised salmon pre-smolts for 6 weeks at two different aerobic training regimes; a continuous intensity training (CT; 0.8bls(-1)) and an interval training (IT; 0.8bl s(-1) 16h and 1.0bl s(-1) 8h) and compared them with untrained controls (C; 0.05bl s(-1)). The effects of endurance training on disease resistance were evaluated using an IPN virus challenge test, while the cardiac immune modulatory effects were characterized by qPCR and microarray gene expression analyses. In addition, swimming performance and growth parameters were investigated. Survival after the IPN challenge was higher for IT (74%) fish than for either CT (64%) or C (61%) fish. While both CT and IT groups showed lower cardiac transcription levels of TNF-α, IL-1β and IL-6 prior to the IPN challenge test, IT fish showed the strongest regulation of genes involved in immune responses and other processes known to affect disease resistance. Both CT and IT regimes resulted in better growth compared with control fish, with CT fish developing a better swimming efficiency during training. Overall, interval aerobic training improved growth and increased robustness of Atlantic salmon, manifested by better disease resistance, which we found was associated with a modulation of relevant gene classes on the cardiac transcriptome. Copyright © 2011 Elsevier Inc. All rights reserved.

  12. Broadened population-level frequency tuning in the auditory cortex of tinnitus patients.

    Science.gov (United States)

    Sekiya, Kenichi; Takahashi, Mariko; Murakami, Shingo; Kakigi, Ryusuke; Okamoto, Hidehiko

    2017-03-01

    Tinnitus is a phantom auditory perception without an external sound source and is one of the most common public health concerns that impair the quality of life of many individuals. However, its neural mechanisms remain unclear. We herein examined population-level frequency tuning in the auditory cortex of unilateral tinnitus patients with similar hearing levels in both ears using magnetoencephalography. We compared auditory-evoked neural activities elicited by a stimulation to the tinnitus and nontinnitus ears. Objective magnetoencephalographic data suggested that population-level frequency tuning corresponding to the tinnitus ear was significantly broader than that corresponding to the nontinnitus ear in the human auditory cortex. The results obtained support the hypothesis that pathological alterations in inhibitory neural networks play an important role in the perception of subjective tinnitus.NEW & NOTEWORTHY Although subjective tinnitus is one of the most common public health concerns that impair the quality of life of many individuals, no standard treatment or objective diagnostic method currently exists. We herein revealed that population-level frequency tuning was significantly broader in the tinnitus ear than in the nontinnitus ear. The results of the present study provide an insight into the development of an objective diagnostic method for subjective tinnitus. Copyright © 2017 the American Physiological Society.

  13. Weathering and solute transport to the Salar de Atacama, northern Chile

    Science.gov (United States)

    Hynek, S. A.; Munk, L. A.; Boutt, D. F.

    2013-12-01

    , and 4) the least radiogenic 87/86 ratios which are found along the western margin of the basin and may have their source in the Cordillera Domeyko. The Sr isotope composition of brine in Salar de Atacama is dominated by sources from the Neogene to modern volcanic arc along its eastern margin. Lithium isotope ratios of freshwater influx are depleted in lithium-7 compared to the brines, and brackish waters are transitional between the two. These data implicate precipitation and/or dissolution of secondary minerals, as the majority of these processes take place where freshwater interacts with evaporite minerals, brackish water, and brines. The lithium isotopic composition of water draining the volcanic arc suggest a limited role for precipitation of Li-bearing secondary minerals associated with freshwater solute fluxes in surface and shallow groundwater. Near surface solute fluxes are constrained by concentrations of tritium, an anthropogenic radioisotope of hydrogen indicative of groundwater recharge (and residence times) within the last 60 years. This multi-isotope approach demonstrates how isotope geochemistry can identify and constrain important processes, pathways and timescales in the Critical Zone.

  14. Antecedentes hidroquímicos del Salar de Aguas Calientes I (Chile

    Directory of Open Access Journals (Sweden)

    Ingrid Garcés Millas

    2012-01-01

    Full Text Available El Salar de Aguas Calientes I es un sistema salino del Altiplano chileno, situado a4.280 m.s.n.m, expuesto a condiciones ambientales áridas. El presente trabajo da cuenta del estudio hidroquímico de las soluciones superficiales existentes en el salar, tanto de soluciones diluidas como concentradas en surgencias y acumulaciones lacustres, así como de la mineralogía de las sales precipitadas por evaporación de estas aguas lacustres. Los principales aportes de agua al salar ingresan por la zona norte y por el sector sur, siendo estos últimos de carácter termal. Los restantes aportes se limitan a escasas precipitaciones en forma de escorrentía superficial o subsuperficial. Todas estas aguas circulan hacia las zonas más bajas del salar, y se acumulan en distintos puntos a lo largo de su sector occidental como consecuencia de un ligero basculamiento en su superficie. Los resultados del análisis químico indican que, a pesar de tratarse de aguas con grados de concentración variable y que oscilan entre muy diluidas y altamente concentradas, todas ellas pertenecen al tipo químico Na-Cl, debido a la interacción de las aguas con los depósitos salinos preexistentes en el salar, en los que predominan halita y yeso. Además, todas las soluciones mostraron elevados contenidos en elementos químicos asociados a actividad hidrotermal como son Li, B y As, encontrándose este último en rangos de toxicidad incluso en las muestras diluidas. En el margen norte del salar, las aguas de una surgencia no termal caracterizadas por ser de muy baja concentración en sales minerales, discurren hacia el salar,alimentando una zona de bofedal en la que se desarrolla importante vida vegetal y sirven de sustento a los rebaños de camélidos del área. En cambio, las aguas de los sectores central y meridional (donde se encuentra una surgencia de carácter termal son mucho más concentradas, acumulándose en lagunas desprovistas de desarrollo vegetal. El an

  15. Active shortening and intermontane basin formation in the central Puna Plateau: Salar de Pocitos, NW Argentina (24°37'S, 67°03'W)

    Science.gov (United States)

    Strecker, Manfred; Bookhagen, Bodo; Freymark, Jessica; Pingel, Heiko; Alonso, Ricardo N.

    2015-04-01

    Similar to other Cenozoic orogenic plateaus, extensional tectonics associated with mafic volcanism typifies the Altiplano-Puna of the southern Central Andes, while the flanks of the plateau and adjacent foreland areas experience shortening. Extensional tectonism in the plateau region since the late Miocene has been explained with delamination of lithospheric mantle. However, new evidence for protracted basin-wide shortening in the Salar de Pocitos region in the south-central Puna documents that the kinematic changeover from shortening to extension is highly diachronous. In this study we assess the deformation and geomorphic history of the Salar de Pocitos region using DGPS surveys, CRN dating of deformed pediment surfaces, and U/Pb dating of volcanic ash horizons in deformed strata. With average elevations of about 3.7 km the Altiplano-Puna is a first-order morphotectonic province of the southern central Andes and constitutes the world's second largest orogenic plateau. With few exceptions the Andean plateau consists of internally drained, partly coalesced sedimentary basins that are mainly bordered by reverse-fault bounded ranges, 5 to 6 km high. While there are many unifying plateau characteristics in the Altiplano (north) and Puna (south), including internal drainage, semi-arid to arid climate and associated deposition of evaporites, there are notable differences between both plateau sectors. In contrast to the vast Altiplano basin of Bolivia, the Argentine Puna comprises numerous, smaller and partly coalesced basins that reflect continued comparmentalization by the combined effects of tectonism and volcanic activity. The N-S oriented Salar de Pocitos basin is the vestige of a formerly contiguous sedimentary basin within the Puna interior. Unlike many other basins in this region it is bordered by the limb of an anticline developed in Tertiary sedimentary rocks on the west, while the eastern border is a reverse-faulted range front. To the north and south the

  16. Population level of microbiota in colon of brestfed infants with acute colienteritis

    Directory of Open Access Journals (Sweden)

    D. V. Rotar

    2017-06-01

    Full Text Available Introduction: Despite the undeniable successes in the study of etiology and pathogenesis of acute intestinal infections in children made in recent decades, unfortunately, its’ result does not guarantee clear determination of etiology and mechanisms of development of the disease. This makes impossible to conduct a successful therapy and prevention. Aim: To determine the quantitative changes of microbiome in colon cavity in breastfed infants suffering from colienteritis. Material and methods: Content of colon cavity of 48 children (one to six months old suffered from colienteritis, which was studied with microbiological examination (control group – 35 samples of colon content of practically healthy children. Results: It was revealed that population level of Bifidobacteria in colon cavity in breastfed infants suffering from colienteritis reaches 10.87±0.79 lg CFU/g, Lactobacilli is lower by 12.29 %, Bacteroides – 51.39 %, Escherichia - by 36.39 %. This leads to the contamination of colon with pathogenic E. coli Hly+ in 27.08 % (7.79±0.27 lg CFU/g. Smaller (6.50±0.22 lg CFU/g population level is found in enteropathogenic Escherichia that contaminate biotope in 29.17 % of patients. There is experiencing elevation of population level of Staphylococci by 2.10 times and colonization of the biotope by pathogenic Escherichia (E. coli Hly+, EPEC and conditionally pathogenic Enterobacteria (Proteus spp., C. diversus, Peptococus. The results demonstrated that in majority of sick children there is formation of dysbacteriosis of I stage, and in other one (35.41 % - II-III stages. Conclusions: Acute colienteritis in one to six months old children, who are bestfeded, develops on the background of prevailing colon dysbiosis of I – III stages. This disturbancy is formed by reducing the number of Bifidobacteria and Lactobacilli and the contamination of colon with E. coli Hly +, enteropathogenic Escherichia and C. diversus, Proteus spp., Peptococi

  17. Population-level impacts of pesticide-induced chronic effects on individuals depend more on ecology than toxicology

    DEFF Research Database (Denmark)

    Dalkvist, Trine; Topping, Christopher John; Forbes, Valery E.

    2009-01-01

    at the population-level. Here we demonstrate how, using ABM modelling, assessments at the population-level can be obtained even for a pesticide with complex long-term effects such as epigenetic transmission of reproductive depression. By objectively fitting nonlinear models to the simulation outputs it was possible...

  18. Sulphated glycosaminoglycans and proteoglycans in the developing vertebral column of juvenile Atlantic salmon (Salmo salar)

    OpenAIRE

    Hannesson, Kirsten O.; Ytteborg, Elisabeth; Takle, Harald; Enersen, Grethe; B?verfjord, Grete; Mona E Pedersen

    2015-01-01

    In the present study, the distribution of sulphated glycosaminoglycans (GAGs) in the developing vertebral column of Atlantic salmon (Salmo salar) at 700, 900, 1100 and 1400?d? was examined by light microscopy. The mineralization pattern was outlined by Alizarin red S and soft structures by Alcian blue. The temporal and spatial distribution patterns of different types of GAGs: chondroitin-4-sulphate/dermatan sulphate, chondroitin-6-sulphate, chondroitin-0-sulphate and keratan sulphate were add...

  19. Genetic Analysis of a Population of Atlantic salmon (Salmo salar, L.)in the Rhine System

    OpenAIRE

    Papa, Laura

    2009-01-01

    The present study was developed under the guidelines of a regional project to support the management of the anadromous salmonids in the Rhine, particularly the reintroduction of the Atlantic salmon (Salmo salar, L.) The main aim was to assign the salmons ascending to the Iffezheim lock to salmons used for reintroduction in the Rhine. It was analysed if such an assignment was reasonably possible. Furthermore, we wanted to find out if an established Rhine population already exists. The Ph.D. st...

  20. Microbial diversity of the hypersaline and lithium-rich Salar de Uyuni, Bolivia.

    Science.gov (United States)

    Haferburg, Götz; Gröning, Janosch A D; Schmidt, Nadja; Kummer, Nicolai-Alexeji; Erquicia, Juan Carlos; Schlömann, Michael

    2017-06-01

    Salar de Uyuni, situated in the Southwest of the Bolivian Altiplano, is the largest salt flat on Earth. Brines of this athalassohaline hypersaline environment are rich in lithium and boron. Due to the ever- increasing commodity demand, the industrial exploitation of brines for metal recovery from the world's biggest lithium reservoir is likely to increase substantially in the near future. Studies on the composition of halophilic microbial communities in brines of the salar have not been published yet. Here we report for the first time on the prokaryotic diversity of four brine habitats across the salar. The brine is characterized by salinity values between 132 and 177 PSU, slightly acidic to near-neutral pH and lithium and boron concentrations of up to 2.0 and 1.4g/L, respectively. Community analysis was performed after sequencing the V3-V4 region of the 16S rRNA genes employing the Illumina MiSeq technology. The mothur software package was used for sequence processing and data analysis. Metagenomic analysis revealed the occurrence of an exclusively archaeal community comprising 26 halobacterial genera including only recently identified genera like Halapricum, Halorubellus and Salinarchaeum. Despite the high diversity of the halobacteria-dominated community in sample P3 (Shannon-Weaver index H'=3.12 at 3% OTU cutoff) almost 40% of the Halobacteriaceae-assigned sequences could not be classified on the genus level under stringent filtering conditions. Even if the limited taxonomic resolution of the V3-V4 region for halobacteria is considered, it seems likely to discover new, hitherto undescribed genera of the family halobacteriaceae in this particular habitat of Salar de Uyuni in future. Copyright © 2017 Elsevier GmbH. All rights reserved.

  1. Use of Social Networking Sites and Risk of Cyberbullying Victimization: A Population-Level Study of Adolescents.

    Science.gov (United States)

    Sampasa-Kanyinga, Hugues; Hamilton, Hayley A

    2015-12-01

    Social networking sites (SNSs) have gained considerable popularity among youth in recent years; however, there is a noticeable paucity of research examining the association between the use of these web-based platforms and cyberbullying victimization at the population level. This study examines the association between the use of SNSs and cyberbullying victimization using a large-scale survey of Canadian middle and high school students. Data on 5,329 students aged 11-20 years were derived from the 2013 Ontario Student Drug Use and Health Survey. Logistic regression was used to examine the relationship between the use of SNSs and cyberbullying victimization while adjusting for covariates. Overall, 19 percent of adolescents were cyberbullied in the past 12 months. Adolescents who were female, younger, of lower socioeconomic status, and who used alcohol or tobacco were at greater odds of being cyberbullied. The use of SNSs was associated with an increased risk of cyberbullying victimization in a dose-response manner (p-trend <0.001). Gender was not a significant moderator of the association between use of SNSs and being cyberbullied. Results from this study underscore the need for raising awareness and educating adolescents on effective strategies to prevent cyberbullying victimization.

  2. Population-level interventions to reduce alcohol-related harm: an overview of systematic reviews.

    Science.gov (United States)

    Martineau, Fred; Tyner, Elizabeth; Lorenc, Theo; Petticrew, Mark; Lock, Karen

    2013-10-01

    To analyse available review-level evidence on the effectiveness of population-level interventions in non-clinical settings to reduce alcohol consumption or related health or social harm. Health, social policy and specialist review databases between 2002 and 2012 were searched for systematic reviews of the effectiveness of population-level alcohol interventions on consumption or alcohol-related health or social outcomes. Data were extracted on review research aim, inclusion criteria, outcome indicators, results, conclusions and limitations. Reviews were quality-assessed using AMSTAR criteria. A narrative synthesis was conducted overall and by policy area. Fifty-two reviews were included from ten policy areas. There is good evidence for policies and interventions to limit alcohol sale availability, to reduce drink-driving, to increase alcohol price or taxation. There is mixed evidence for family- and community-level interventions, school-based interventions, and interventions in the alcohol server setting and the mass media. There is weak evidence for workplace interventions and for interventions targeting illicit alcohol sales. There is evidence of the ineffectiveness of interventions in higher education settings. There is a pattern of support from the evidence base for regulatory or statutory enforcement interventions over local non-regulatory approaches targeting specific population groups. © 2013.

  3. Individual and population level effects of partner notification for Chlamydia trachomatis.

    Directory of Open Access Journals (Sweden)

    Christian L Althaus

    Full Text Available Partner notification (PN or contact tracing is an important aspect of treating bacterial sexually transmitted infections (STIs, such as Chlamydia trachomatis. It facilitates the identification of new infected cases that can be treated through individual case management. PN also acts indirectly by limiting onward transmission in the general population. However, the impact of PN, both at the level of individuals and the population, remains unclear. Since it is difficult to study the effects of PN empirically, mathematical and computational models are useful tools for investigating its potential as a public health intervention. To this end, we developed an individual-based modeling framework called Rstisim. It allows the implementation of different models of STI transmission with various levels of complexity and the reconstruction of the complete dynamic sexual partnership network over any time period. A key feature of this framework is that we can trace an individual's partnership history in detail and investigate the outcome of different PN strategies for C. trachomatis. For individual case management, the results suggest that notifying three or more partners from the preceding 18 months yields substantial numbers of new cases. In contrast, the successful treatment of current partners is most important for preventing re-infection of index cases and reducing further transmission of C. trachomatis at the population level. The findings of this study demonstrate the difference between individual and population level outcomes of public health interventions for STIs.

  4. Social learning may lead to population level conformity without individual level frequency bias.

    Science.gov (United States)

    Eriksson, Kimmo; Cownden, Daniel; Strimling, Pontus

    2017-12-11

    A requirement of culture, whether animal or human, is some degree of conformity of behavior within populations. Researchers of gene-culture coevolution have suggested that population level conformity may result from frequency-biased social learning: individuals sampling multiple role models and preferentially adopting the majority behavior in the sample. When learning from a single role model, frequency-bias is not possible. We show why a population-level trend, either conformist or anticonformist, may nonetheless be almost inevitable in a population of individuals that learn through social enhancement, that is, using observations of others' behavior to update their own probability of using a behavior in the future. The exact specification of individuals' updating rule determines the direction of the trend. These results offer a new interpretation of previous findings from simulations of social enhancement in combination with reinforcement learning, and demonstrate how results of dynamical models may strongly depend on seemingly innocuous choices of model specifications, and how important it is to obtain empirical data on which to base such choices.

  5. Microbial Activity Response to Solar Radiation across Contrasting Environmental Conditions in Salar de Huasco, Northern Chilean Altiplano

    Science.gov (United States)

    Hernández, Klaudia L.; Yannicelli, Beatriz; Olsen, Lasse M.; Dorador, Cristina; Menschel, Eduardo J.; Molina, Verónica; Remonsellez, Francisco; Hengst, Martha B.; Jeffrey, Wade H.

    2016-01-01

    In high altitude environments, extreme levels of solar radiation and important differences of ionic concentrations over narrow spatial scales may modulate microbial activity. In Salar de Huasco, a high-altitude wetland in the Andean mountains, the high diversity of microbial communities has been characterized and associated with strong environmental variability. Communities that differed in light history and environmental conditions, such as nutrient concentrations and salinity from different spatial locations, were assessed for bacterial secondary production (BSP, 3H-leucine incorporation) response from short-term exposures to solar radiation. We sampled during austral spring seven stations categorized as: (a) source stations, with recently emerged groundwater (no-previous solar exposure); (b) stream running water stations; (c) stations connected to source waters but far downstream from source points; and (d) isolated ponds disconnected from ground sources or streams with a longer isolation and solar exposure history. Very high values of 0.25 μE m-2 s-1, 72 W m-2 and 12 W m-2 were measured for PAR, UVA, and UVB incident solar radiation, respectively. The environmental factors measured formed two groups of stations reflected by principal component analyses (near to groundwater sources and isolated systems) where isolated ponds had the highest BSP and microbial abundance (35 microalgae taxa, picoeukaryotes, nanoflagellates, and bacteria) plus higher salinities and PO43- concentrations. BSP short-term response (4 h) to solar radiation was measured by 3H-leucine incorporation under four different solar conditions: full sun, no UVB, PAR, and dark. Microbial communities established in waters with the longest surface exposure (e.g., isolated ponds) had the lowest BSP response to solar radiation treatments, and thus were likely best adapted to solar radiation exposure contrary to ground source waters. These results support our light history (solar exposure) hypothesis

  6. Microbial activity response to solar radiation across contrasting environmental conditions in Salar de Huasco, Northern Chilean Altiplano

    Directory of Open Access Journals (Sweden)

    Klaudia Liliana Hernández

    2016-11-01

    Full Text Available In high altitude environments, extreme levels of solar radiation and important differences of ionic concentrations over narrow spatial scales may modulate microbial activity. In Salar de Huasco, a high-altitude wetland in the Andean mountains, the high diversity of microbial communities has been characterized and associated with strong environmental variability. Communities that differed in light history and environmental conditions, such as nutrient concentrations and salinity from different spatial locations, were assessed for bacterial secondary production (3H-leucine incorporation, BSP response from short-term exposures to solar radiation. We sampled during austral spring seven stations categorized as: a source stations, with recently emerged groundwater (no-previous solar exposure; b stream running water stations; c stations connected to source waters but far downstream from source points; and d isolated ponds disconnected from ground sources or streams with a longer isolation and solar exposure history. Very high values of 0.25 µE m-2 s-1, 72 W m-2 and 12 Wm-2 were measured for PAR, UVA, and UVB incident solar radiation, respectively. The environmental factors measured formed two groups of stations reflected by PCA analyses (near to groundwater sources and isolated systems where isolated ponds had the highest BSP and microbial abundance (35 microalgae taxa, picoeukaryotes, nanoflagellates and bacteria plus higher salinities and PO43- concentrations. BSP short-term response (4 h to solar radiation was measured by 3H-Leucine incorporation under four different solar conditions: full sun, no UVB, PAR, and dark. Microbial communities established in waters with the longest surface exposure (e.g. isolated ponds had the lowest BSP response to solar radiation treatments, and thus were likely best adapted to solar radiation exposure contrary to ground source waters. These results support our light history (solar exposure hypothesis where the more

  7. Microbial Activity Response to Solar Radiation across Contrasting Environmental Conditions in Salar de Huasco, Northern Chilean Altiplano.

    Science.gov (United States)

    Hernández, Klaudia L; Yannicelli, Beatriz; Olsen, Lasse M; Dorador, Cristina; Menschel, Eduardo J; Molina, Verónica; Remonsellez, Francisco; Hengst, Martha B; Jeffrey, Wade H

    2016-01-01

    In high altitude environments, extreme levels of solar radiation and important differences of ionic concentrations over narrow spatial scales may modulate microbial activity. In Salar de Huasco, a high-altitude wetland in the Andean mountains, the high diversity of microbial communities has been characterized and associated with strong environmental variability. Communities that differed in light history and environmental conditions, such as nutrient concentrations and salinity from different spatial locations, were assessed for bacterial secondary production (BSP, 3 H-leucine incorporation) response from short-term exposures to solar radiation. We sampled during austral spring seven stations categorized as: (a) source stations, with recently emerged groundwater (no-previous solar exposure); (b) stream running water stations; (c) stations connected to source waters but far downstream from source points; and (d) isolated ponds disconnected from ground sources or streams with a longer isolation and solar exposure history. Very high values of 0.25 μE m -2 s -1 , 72 W m -2 and 12 W m -2 were measured for PAR, UVA, and UVB incident solar radiation, respectively. The environmental factors measured formed two groups of stations reflected by principal component analyses (near to groundwater sources and isolated systems) where isolated ponds had the highest BSP and microbial abundance (35 microalgae taxa, picoeukaryotes, nanoflagellates, and bacteria) plus higher salinities and PO 4 3- concentrations. BSP short-term response (4 h) to solar radiation was measured by 3 H-leucine incorporation under four different solar conditions: full sun, no UVB, PAR, and dark. Microbial communities established in waters with the longest surface exposure (e.g., isolated ponds) had the lowest BSP response to solar radiation treatments, and thus were likely best adapted to solar radiation exposure contrary to ground source waters. These results support our light history (solar exposure

  8. Multi-temporal remote sensing analysis of salars in El Loa Province, Chile: Implications for water resource management

    Science.gov (United States)

    Markovich, K.; Pierce, S. A.

    2011-12-01

    Salar de Ascotán and Salar de Carcote are internally drained, evaporative basins located in the Atacama Desert, 200 km northeast of Antofogasta in Region II, Chile. The two salars are part of a regional groundwater system that recharges in the adjacent uplands to the east and terminates in the regional topographic low at Salar de Uyuni, Bolivia. This regional groundwater system is discharged locally as spring-fed perennial surface water that flows across the salar surface and either evaporates, or reinfiltrates, in lagoon-like environments. This perennial surface water supports diverse flora and fauna in the salar basins, including flamingo, vicuña, and the endemic fish species Orestias ascotanensis. Mining projects in the region began pumping the groundwater system in the Ascotán basin in the mid-1990's, leading to concern about the preservation of spring-fed surface flows. While hydrologic and ecologic monitoring efforts have been coordinated, data collection is limited to in-situ measurements and antecedent records precede extraction by approximately six months. Remote sensing can provide a means for large scale monitoring of the salars, as well as providing additional historical data to support environmental management of the systems. This comparative study utilizes satellite imagery to detect changes in surface water extent in the two salars and evaluate the results for possible correlation with climatic and/or anthropogenic factors. Landsat TM and ETM+ images from the time period of 1986-2011 are analyzed for surface water extent, and geographic information technologies are used to integrate the remotely sensed data with in-situ measurements. Early results indicate that surface water extent on the salar surface has diminished from 1986 and present day conditions. The decrease is most pronounced in the Ascotán basin, suggesting a possible correlation to anthropogenic influences. Also, the rate of decrease in surface water presence is most elevated in the

  9. The relationship of sugar to population-level diabetes prevalence: an econometric analysis of repeated cross-sectional data.

    Science.gov (United States)

    Basu, Sanjay; Yoffe, Paula; Hills, Nancy; Lustig, Robert H

    2013-01-01

    While experimental and observational studies suggest that sugar intake is associated with the development of type 2 diabetes, independent of its role in obesity, it is unclear whether alterations in sugar intake can account for differences in diabetes prevalence among overall populations. Using econometric models of repeated cross-sectional data on diabetes and nutritional components of food from 175 countries, we found that every 150 kcal/person/day increase in sugar availability (about one can of soda/day) was associated with increased diabetes prevalence by 1.1% (p <0.001) after testing for potential selection biases and controlling for other food types (including fibers, meats, fruits, oils, cereals), total calories, overweight and obesity, period-effects, and several socioeconomic variables such as aging, urbanization and income. No other food types yielded significant individual associations with diabetes prevalence after controlling for obesity and other confounders. The impact of sugar on diabetes was independent of sedentary behavior and alcohol use, and the effect was modified but not confounded by obesity or overweight. Duration and degree of sugar exposure correlated significantly with diabetes prevalence in a dose-dependent manner, while declines in sugar exposure correlated with significant subsequent declines in diabetes rates independently of other socioeconomic, dietary and obesity prevalence changes. Differences in sugar availability statistically explain variations in diabetes prevalence rates at a population level that are not explained by physical activity, overweight or obesity.

  10. Dietary soya saponins increase gut permeability and play a key role in the onset of soyabean-induced enteritis in Atlantic salmon (Salmo salar L.)

    DEFF Research Database (Denmark)

    Knudsen, Sven David Lausten; Jutfelt, Fredrik; Sundh, Henrik

    2008-01-01

    are naturally occurring amphiphilic molecules and have been associated with many biological activities. The aim of the present study was to investigate whether soya saponins trigger the onset of soyabean-induced enteritis in Atlantic salmon (Salmo salar L.), and to examine if dietary soya saponins...... increase the epithelial permeability of the distal intestine in Atlantic salmon. Seven experimental diets containing different levels of soya saponins were fed to seawater-adapted Atlantic salmon for 53 d. The diets included a fishmeal-based control diet, two fishmeal-based diets with different levels...... of added soya saponins, one diet containing 25 % lupin kernel meal, two diets based on 25 % lupin kernel meal with different levels of added soya saponins, and one diet containing 25 % defatted soyabean meal. The effect on intestinal morphology, intestinal epithelial permeability and faecal DM content...

  11. Population-level impact and herd effects following human papillomavirus vaccination programmes

    DEFF Research Database (Denmark)

    Drolet, Mélanie; Bénard, Élodie; Boily, Marie-Claude

    2015-01-01

    -vaccination and post-vaccination periods, in the incidence or prevalence of at least one HPV-related endpoint: HPV infection, anogenital warts, and high-grade cervical lesions. We used random-effects models to derive pooled relative risk (RR) estimates. We stratified all analyses by age and sex. We did subgroup......BACKGROUND: Human papillomavirus (HPV) vaccination programmes were first implemented in several countries worldwide in 2007. We did a systematic review and meta-analysis to assess the population-level consequences and herd effects after female HPV vaccination programmes, to verify whether...... or not the high efficacy reported in randomised controlled clinical trials are materialising in real-world situations. METHODS: We searched the Medline and Embase databases (between Jan 1, 2007 and Feb 28, 2014) and conference abstracts for time-trend studies that analysed changes, between the pre...

  12. Effect of ectoparasite infestation density and life history stages on the swimming performance of Atlantic salmon Salmo salar

    Directory of Open Access Journals (Sweden)

    Samantha Bui

    2016-06-01

    Full Text Available To overcome sustainability obstacles and improve operations, the Atlantic salmon farming industry is testing novel approaches to production. Redistributing farm sites to offshore locations is one such solution; however, tolerance to high-current velocity sites must be considered, particularly if fish health status is compromised by parasites. We tested the effect of parasite density and life-history stage on the swimming performance of Atlantic salmon Salmo salar using a swim flume. Salmon with 3 different salmon lice Lepeophtheirus salmonis densities (0, 0.02 � 0.01 and 0.11 � 0.01 lice cm-2 [mean � SE] were tested across the 4 major life-history stages of lice (copepodid, chalimus, pre-adult and adult for critical swimming performance (Ucrit. Salmon Ucrit declined slightly by a mean of 0.04 to 0.10 body lengths s-1 with high parasite densities compared to uninfested and low densities, across the lice stages, while progression through the parasite life-history stages had little effect on swimming performance. Our results suggest that increasing infestation density of salmon lice incurs negative fitness consequences for farmed Atlantic salmon held in high-current velocity sites, with little difference in costs associated with attachment by different life-history stages of the lice.

  13. Anesthesia induces stress in Atlantic salmon (Salmo salar), Atlantic cod (Gadus morhua) and Atlantic halibut (Hippoglossus hippoglossus).

    Science.gov (United States)

    Zahl, Inger Hilde; Kiessling, Anders; Samuelsen, Ole Bent; Olsen, Rolf Erik

    2010-09-01

    Stress in response to anesthesia with benzocaine, MS-222, metomidate and isoeugenol was studied in Atlantic salmon (Salmo salar), Atlantic halibut (Hippoglossus hippoglossus), and Atlantic cod (Gadus morhua) with no concomitant stress from handling or confinement in association with anesthesia or sampling. All of the anesthetics tested induced a stress response in all species, displayed by a release of cortisol to the water. MS-222 anesthesia elicited the highest cortisol release rates, reaching maximum levels 0.5 h post-exposure and returning to basal levels after 3-4 h. Benzocaine anesthesia caused a bimodal response where the initial peak in cortisol release rate was followed by a second increase lasting towards the end of the trial (6 h). This bimodality was more profound in Atlantic salmon than in Atlantic halibut and Atlantic cod. Metomidate anesthesia induced the lowest release of cortisol of the agents tested in both Atlantic halibut and Atlantic cod, but resulted in a bimodal response in Atlantic salmon where the initial increase in cortisol release was followed by a larger increase peaking at 2-2.5 h post exposure before returning to basal levels after 5 h. The stress induced in Atlantic salmon by isoeugenol anesthesia resembled that of MS-222, but did not reach the same elevated level. Overall, the cortisol release was most profound in Atlantic salmon followed by Atlantic halibut and Atlantic cod.

  14. Baking reduces prostaglandin, resolvin, and hydroxy-fatty acid content of farm-raised Atlantic salmon (Salmo salar).

    Science.gov (United States)

    Raatz, Susan K; Golovko, Mikhail Y; Brose, Stephen A; Rosenberger, Thad A; Burr, Gary S; Wolters, William R; Picklo, Matthew J

    2011-10-26

    The consumption of seafood enriched in n-3 polyunsaturated fatty acids (PUFA) is associated with a decreased risk of cardiovascular disease. Several n-3 oxidation products from eicosapentaenoic acid (EPA; 20:5n-3) and docosahexaenoic acid (22:6n-3) have known protective effects in the vasculature. It is not known whether the consumption of cooked seafood enriched in n-3 PUFA causes appreciable consumption of lipid oxidation products. We tested the hypothesis that baking Atlantic salmon (Salmo salar) increases the level of n-3 and n-6 PUFA oxidation products over raw salmon. We measured the contents of several monohydroxy-fatty acids (MHFA), prostanoids, and resolvins. Our data demonstrate that baking did not change the overall total levels of MHFA. However, baking resulted in selective regioisomeric loss of hydroxy fatty acids from arachidonic acid (20:4n-6) and EPA, while significantly increasing hydroxyl-linoleic acid levels. The contents of prostanoids and resolvins were reduced several-fold with baking. The inclusion of a coating on the salmon prior to baking reduced the loss of some MHFA but had no effect on prostanoid losses incurred by baking. Baking did not decrease n-3 PUFA contents, indicating that baking of salmon is an acceptable means of preparation that does not alter the potential health benefits of high n-3 seafood consumption. The extent to which the levels of MHFA, prostanoids, and resolvins in the raw or baked fish have physiologic consequence for humans needs to be determined.

  15. Population-level impact of active tuberculosis case finding in an Asian megacity.

    Directory of Open Access Journals (Sweden)

    David W Dowdy

    Full Text Available BACKGROUND: The potential population-level impact of private-sector initiatives for tuberculosis (TB case finding in Southeast Asia remains uncertain. In 2011, the Indus Hospital TB Control Program in Karachi, Pakistan, undertook an aggressive case-finding campaign that doubled notification rates, providing an opportunity to investigate potential population-level effects. METHODS: We constructed an age-structured compartmental model of TB in the intervention area. We fit the model using field and literature data, assuming that TB incidence equaled the estimated nationwide incidence in Pakistan (primary analysis, or 1.5 times greater (high-incidence scenario. We modeled the intervention as an increase in the rate of formal-sector TB diagnosis and evaluated the potential impact of sustaining this rate for five years. RESULTS: In the primary analysis, the five-year intervention averted 24% (95% uncertainty range, UR: 18-30% of five-year cumulative TB cases and 52% (95% UR: 45-57% of cumulative TB deaths. Corresponding reductions in the high-incidence scenario were 12% (95% UR: 8-17% and 27% (95% UR: 21-34%, although the absolute number of lives saved was higher. At the end of five years, TB notification rates in the primary analysis were below their 2010 baseline, incidence had dropped by 45%, and annual mortality had fallen by 72%. About half of the cumulative impact on incidence and mortality could be achieved with a one-year intervention. CONCLUSIONS: Sustained, multifaceted, and innovative approaches to TB case-finding in Asian megacities can have substantial community-wide epidemiological impact.

  16. Population-level preferences for primary care physicians' characteristics in Japan: a structural equation modeling.

    Science.gov (United States)

    Takahashi, Osamu; Ohde, Sachiko; Jacobs, Joshua L; Tokuda, Yasuharu; Yanai, Haruo; Okubo, Tomoya; Shimbo, Takuro; Fukuhara, Shunichi; Hinohara, Shigeaki; Fukui, Tsuguya

    2010-01-01

    Primary care has potential to play a role for improving the patient care in Japanese health care system; however, little information is available about how patients perceive the roles of primary care physicians (PCPs) within the Japanese health care system. We aimed to assess population-level preferences for PCPs and investigated the extent to which preferences vary in relation to different population groups in Japan. Data were extracted from a cross-sectional questionnaire survey in October 2003. An 18-item questionnaire was used to measure the preferences for PCPs. Exploratory factor analysis was performed to identify latent factors, while confirmatory factor analysis was used to evaluate the fit of the structure using structural equation modeling (SEM). Nationally representative sample of the adult Japanese general population was chosen by controlling for age, sex, and the size of cities. A total of 2,453 adults>or=18-years-old were analyzed. SEM provided a 4-factor structural model of the population-level preference for PCPs, such as clinical competence (path coefficient (pc)=0.72), gate-keeping (pc=0.64), communication with patients or specialists (pc=0.49) and high education (pc=0.25) and demonstrated the best goodness-of-fit. Those who were middle aged, have a high family income, and a high level of education, placed more importance on gate-keeping characteristics, and the rural residents emphasized communication rather than clinical competence. Our results indicate that the preferences for PCPs are divided into four main factors and underscore the variation among preferences according to different population groups, such as age, socioeconomic and educational status, and places of living. These variations should be considered to improve the primary care system in Japan.

  17. Broadened population-level frequency tuning in human auditory cortex of portable music player users.

    Directory of Open Access Journals (Sweden)

    Hidehiko Okamoto

    Full Text Available Nowadays, many people use portable players to enrich their daily life with enjoyable music. However, in noisy environments, the player volume is often set to extremely high levels in order to drown out the intense ambient noise and satisfy the appetite for music. Extensive and inappropriate usage of portable music players might cause subtle damages in the auditory system, which are not behaviorally detectable in an early stage of the hearing impairment progress. Here, by means of magnetoencephalography, we objectively examined detrimental effects of portable music player misusage on the population-level frequency tuning in the human auditory cortex. We compared two groups of young people: one group had listened to music with portable music players intensively for a long period of time, while the other group had not. Both groups performed equally and normally in standard audiological examinations (pure tone audiogram, speech test, and hearing-in-noise test. However, the objective magnetoencephalographic data demonstrated that the population-level frequency tuning in the auditory cortex of the portable music player users was significantly broadened compared to the non-users, when attention was distracted from the auditory modality; this group difference vanished when attention was directed to the auditory modality. Our conclusion is that extensive and inadequate usage of portable music players could cause subtle damages, which standard behavioral audiometric measures fail to detect in an early stage. However, these damages could lead to future irreversible hearing disorders, which would have a huge negative impact on the quality of life of those affected, and the society as a whole.

  18. Evaluation of population-level ecological risks of fish-eating birds to dioxinlike PCBs exposure

    Energy Technology Data Exchange (ETDEWEB)

    Naito, Wataru; Yoshida, Kikuo [National Institute of Advanced Industrial Science and Technology, Research Center for Chemical Risk Management, Tsukuba (Japan); Murata, Mariko [National Institute of Technology and Evaluation, Tokyo (Japan)

    2004-09-15

    Polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/DFs) and some non- and monoortho- polychlorinated biphenyl congeners that can attain planar configuration (dioxinlike PCBs), which are chemically stable and persistent, are thought to be biomagnified via foodchain. Many studies have revealed that higher levels of these compounds have been observed in fish-eating birds, a top consumer in aquatic biota. Among these compounds, Dioxinlike PCBs has contributed more than 80% of the total TEQs found in eggs of fish-eating birds. In order to evaluate the effects of these compounds on fish-eating birds, therefore, it is important to elucidate exposure pathways and characteristics of dioxinlike PCBs. The conventional ecological risk assessment method of chemicals entails comparing the predicted no effect concentration (PNEC) determined from laboratory toxicity tests with the predicted or observed concentration in a target organism or a surrounding environmental media. Utilizing such a result of simplistic individual-level effect to draw conclusions regarding chemical effects on population is, however, questionable. Since risk management decisions should be based on protecting populations, the methods for population-level ecological risk assessment of chemicals have been of increasing interest for risk assessors and managers. In this study, a population-level ecological risk assessment of dioxinlike PCBs on fish-eating birds was performed to judge the need for risk management measures to protect aquatic wildlife from dioxinlike PCBs contamination in Japan. Egg mortality risk and the changes in population growth rate, {lambda}, in relation to the contamination levels of dioxinlike PCBs in eggs of four different types of fish-eating birds were determined by integrating the results from both bioaccumulation and life-history models.

  19. Preconception healthcare delivery at a population level: construction of public health models of preconception care.

    Science.gov (United States)

    Shannon, Geordan D; Alberg, Corinna; Nacul, Luis; Pashayan, Nora

    2014-08-01

    A key challenge of preconception healthcare is identifying how it can best be delivered at a population level. To review current strategies of preconception healthcare, explore methods of preconception healthcare delivery, and develop public health models which reflect different preconception healthcare pathways. Preconception care strategies, programmes and evaluations were identified through a review of Medline and Embase databases. Search terms included: preconception, pre-pregnancy, intervention, primary care, healthcare, model, delivery, program, prevention, trial, effectiveness, congenital disorders OR abnormalities, evaluation, assessment, impact. Inclusion criteria for review articles were: (1) English, (2) human subjects, (3) women of childbearing age, (4) 1980–current data, (5) all countries, (6) both high risk and universal approaches, (7) guidelines or recommendations, (8) opinion articles, (9) experimental studies. Exclusion criteria were: (1) non-human subjects, (2) non-English, (3) outside of the specified timeframe, (4) articles on male healthcare. The results of the literature review were synthesised into public health models of care: (1) primary care; (2) hospital-based and inter-conception care; (3) specific preconception care clinics; and, (4) community outreach. Fifteen evaluations of preconception care were identified. Community programmes demonstrated a significant impact on substance use, folic acid supplementation, diabetes optimization, and hyperphenylalaninemia. An ideal preconception visits entail risk screening, education, and intervention if indicated. Subsequently, four public health models were developed synthesizing preconception care delivery at a population level. Heterogeneity of risk factors, health systems and strategies of care reflect the lack of consensus about the best way to deliver preconception care. The proposed models aim to reflect differing aspects of preconception healthcare delivery.

  20. The Relationship of Sugar to Population-Level Diabetes Prevalence: An Econometric Analysis of Repeated Cross-Sectional Data

    Science.gov (United States)

    Basu, Sanjay; Yoffe, Paula; Hills, Nancy; Lustig, Robert H.

    2013-01-01

    While experimental and observational studies suggest that sugar intake is associated with the development of type 2 diabetes, independent of its role in obesity, it is unclear whether alterations in sugar intake can account for differences in diabetes prevalence among overall populations. Using econometric models of repeated cross-sectional data on diabetes and nutritional components of food from 175 countries, we found that every 150 kcal/person/day increase in sugar availability (about one can of soda/day) was associated with increased diabetes prevalence by 1.1% (p sugar on diabetes was independent of sedentary behavior and alcohol use, and the effect was modified but not confounded by obesity or overweight. Duration and degree of sugar exposure correlated significantly with diabetes prevalence in a dose-dependent manner, while declines in sugar exposure correlated with significant subsequent declines in diabetes rates independently of other socioeconomic, dietary and obesity prevalence changes. Differences in sugar availability statistically explain variations in diabetes prevalence rates at a population level that are not explained by physical activity, overweight or obesity. PMID:23460912

  1. Population-level impacts of pesticide-induced chronic effects on individuals depend more on ecology than toxicology.

    Science.gov (United States)

    Dalkvist, T; Topping, C J; Forbes, V E

    2009-09-01

    The current method for assessing long-term risk of pesticides to mammals in the EU is based on the individual rather than the population-level and lacks ecological realism. Hence there is little possibility for regulatory authorities to increase ecological realism and understanding of risks at the population-level. Here we demonstrate how, using ABM modelling, assessments at the population-level can be obtained even for a pesticide with complex long-term effects such as epigenetic transmission of reproductive depression. By objectively fitting nonlinear models to the simulation outputs it was possible to compare population depression and recovery rates for a range of scenarios in which toxicity and exposure factors were varied. The system was differentially sensitive to the various factors, but vole ecology and behaviour were at least as important predictors of population-level effects as toxicology. This emphasises the need for greater focus on animal ecology in risk assessments.

  2. Launching a salt substitute to reduce blood pressure at the population level: a cluster randomized stepped wedge trial in Peru

    National Research Council Canada - National Science Library

    Bernabe-Ortiz, Antonio; Diez-Canseco, Francisco; Gilman, Robert H; Cárdenas, María K; Sacksteder, Katherine A; Miranda, J Jaime

    2014-01-01

    .... This study aims to estimate the impact of a population-level intervention based on sodium reduction and potassium increase - in practice, introducing a low-sodium, high-potassium salt substitute...

  3. Population-level effects of risk factors for bovine respiratory disease in Australian feedlot cattle.

    Science.gov (United States)

    Hay, K E; Morton, J M; Clements, A C A; Mahony, T J; Barnes, T S

    2017-05-01

    Results obtained from a nationwide longitudinal study were extended to estimate the population-level effects of selected risk factors on the incidence of bovine respiratory disease (BRD) during the first 50days at risk in medium-sized to large Australian feedlots. Population attributable fractions (PAF) and population attributable risks (PAR) were used to rank selected risk factors in order of importance from the perspective of the Australian feedlot industry within two mutually exclusive categories: 'intervention' risk factors had practical strategies that feedlot managers could implement to avoid exposure of cattle to adverse levels of the risk factor and a precise estimate of the population-level effect while 'others' did not. An alternative method was also used to quantify the expected effects of simultaneously preventing exposure to multiple management-related factors whilst not changing exposure to factors that were more difficult to modify. The most important 'intervention' risk factors were shared pen water (PAF: 0.70, 95% credible interval: 0.45-0.83), breed (PAF: 0.67, 95% credible interval: 0.54-0.77), the animal's prior lifetime history of mixing with cattle from other herds (PAF: 0.53, 95% credible interval: 0.30-0.69), timing of the animal's move to the vicinity of the feedlot (PAF: 0.45, 95% credible interval: 0.17-0.68), the presence of Bovine viral diarrhoea virus 1 (BVDV-1) in the animal's cohort (PAF: 0.30, 95% credible interval: 0.04-0.50), the number of study animals in the animal's group 13days before induction (PAF: 0.30, 95% credible interval: 0.10-0.44) and induction weight (PAF: 0.16, 95% credible interval: 0.09-0.23). Other important risk factors identified and prioritised for further research were feedlot region, season of induction and cohort formation patterns. An estimated 82% of BRD incidence was attributable to management-related risk factors, whereby the lowest risk category of a composite management-related variable comprised

  4. Population-level Spatial Access to Prehospital Care by the National Ambulance Service in Ghana.

    Science.gov (United States)

    Tansley, Gavin; Stewart, Barclay; Zakariah, Ahmed; Boateng, Edmund; Achena, Christiana; Lewis, Daniel; Mock, Charles

    2016-01-01

    Conditions requiring emergency treatment disproportionately affect low- and middle-income countries (LMICs), where there is often insufficient prehospital care capacity. To inform targeted prehospital care development in Ghana, we aimed to describe spatial access to formal prehospital care services and identify ambulance stations for capacity expansion. Cost distance methods were used to evaluate areal and population-level access to prehospital care within 30 and 60 minutes of each of the 128 ambulance stations in Ghana. With network analysis methods, a two-step floating catchment area model was created to identify district-level variability in access. Districts without NAS stations within their catchment areas were identified as candidates for an additional NAS station. Additionally, five candidate stations for capacity expansion (e.g., addition of an ambulance) were then identified through iterative simulations that were designed to identify the stations that had the greatest influence on the access scores of the ten lowest access districts. Following NAS inception, the proportion of Ghana's landmass serviceable within 60 minutes of a station increased from 8.7 to 59.4% from 2004 to 2014, respectively. Over the same time period, the proportion of the population with access to the NAS within 60-minutes increased from 48% to 79%. The two-step floating catchment area model identified considerable variation in district-level access scores, which ranged from 0.05 to 2.43 ambulances per 100,000 persons (median 0.45; interquartile range 0.23-0.63). Seven candidate districts for NAS station addition and five candidate NAS stations for capacity expansion were identified. The addition of one ambulance to each of the five candidate stations improved access scores in the ten lowest access districts by a total 0.22 ambulances per 100,000 persons. The NAS in Ghana has expanded its population-level spatial access to the majority of the population; however, access inequality

  5. Families First Home Visiting programme reduces population-level child health and social inequities.

    Science.gov (United States)

    Chartier, Mariette; Nickel, Nathan C; Chateau, Dan; Enns, Jennifer E; Isaac, Michael R; Katz, Alan; Sarkar, Joykrishna; Burland, Elaine; Taylor, Carole; Brownell, Marni

    2018-01-01

    Home visiting has been shown to reduce child maltreatment and improve child health outcomes. In this observational study, we explored whether Families First, a home visiting programme in Manitoba, Canada, decreased population-level inequities in children being taken into care of child welfare and receiving complete childhood immunisations. De-identified administrative health and social services data for children born 2003-2009 in Manitoba were linked to home visiting programme data. Programme eligibility was determined by screening for family risk factors. We compared probabilities of being taken into care and receiving immunisations among programme children (n=4575), eligible children who did not receive the programme (n=5186) and the general child population (n=87 897) and tested inequities using differences of risk differences (DRDs) and ratios of risk ratios (RRRs). Programme children were less likely to be taken into care (probability (95% CI) at age 1, programme 7.5 (7.0 to 8.0) vs non-programme 10.0 (10.0 to 10.1)) and more likely to receive complete immunisations (probability at age 1, programme 77.3 (76.5 to 78.0) vs non-programme 73.2 (72.1 to 74.3)). Inequities between programme children and the general population were reduced for both outcomes (being taken into care at age 1, DRD -2.5 (-3.7 to 1.2) and RRR 0.8 (0.7 to 0.9); complete immunisation at age 1, DRD 4.1 (2.2 to 6.0) and RRR 1.1 (1.0 to 1.1)); these inequities were also significantly reduced at age 2. Home visiting programmes should be recognised as effective strategies for improving child outcomes and reducing population-level health and social inequities. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  6. The Cool Little Kids randomised controlled trial: Population-level early prevention for anxiety disorders

    Directory of Open Access Journals (Sweden)

    Hiscock Harriet

    2011-01-01

    Full Text Available Abstract Background The World Health Organization predicts that by 2030 internalising problems (e.g. depression and anxiety will be second only to HIV/AIDS in international burden of disease. Internalising problems affect 1 in 7 school aged children, impacting on peer relations, school engagement, and later mental health, relationships and employment. The development of early childhood prevention for internalising problems is in its infancy. The current study follows two successful 'efficacy' trials of a parenting group intervention to reduce internalising disorders in temperamentally inhibited preschool children. Cool Little Kids is a population-level randomised trial to determine the impacts of systematically screening preschoolers for inhibition then offering a parenting group intervention, on child internalising problems and economic costs at school entry. Methods/Design This randomised trial will be conducted within the preschool service system, attended by more than 95% of Australian children in the year before starting school. In early 2011, preschool services in four local government areas in Melbourne, Australia, will distribute the screening tool. The ≈16% (n≈500 with temperamental inhibition will enter the trial. Intervention parents will be offered Cool Little Kids, a 6-session group program in the local community, focusing on ways to develop their child's bravery skills by reducing overprotective parenting interactions. Outcomes one and two years post-baseline will comprise child internalising diagnoses and symptoms, parenting interactions, and parent wellbeing. An economic evaluation (cost-consequences framework will compare incremental differences in costs of the intervention versus control children to incremental differences in outcomes, from a societal perspective. Analyses will use the intention-to-treat principle, using logistic and linear regression models (binary and continuous outcomes respectively to compare outcomes

  7. Population-level intervention to promote chlamydia screening. Moving toward implementation of chlamydia hedis 2000 measure

    Science.gov (United States)

    Oh; Grimley; Heudebert

    2000-05-01

    Background: HEDIS 2000 measure includes chlamydia screening in women which is designed to assess the percentage of sexually active women 15 to 25 years who have received at least one screening test for chlamydia during the reporting year. This study is being undertaken to determine feasibility of implementing a population-level intervention within HMOs to promote chlamydia screening. This abstract presents preliminary findings from the Birmingham project of this multicenter study.Methods: In partnerships with two HMOs, series of outreach methods were used in a stepwise fashion to determine potential barriers and enabling factors for the implementation of chlamydia HEDIS measure in a conservative social environment. Mail outreach was sequentially combined with newspaper, TV, radio advertisements and poster displays. Both qualitative and quantitative impact of the outreach efforts were measured across the timeline. The measures included reporting for chlamydia screening (urine LCR) and infection rate, monitoring chlamydia hotline and staffed phoneline use, and assessment of untoward effects and cost-analysis of the chlamydia outreach campaign.Results: The key findings are: the benefit of chlamydia screening is not understood by general public, letters send by Health Plans to their members are not read by many subscribers, and there are wide gaps between adolescents and their parents, in knowledge, attitudes, beliefs in regard to obtaining information and accessing the screening services (teens prefer hotline, brochure in an envelop addressed to teens, incentives for reporting to the clinic for screening, vs. parents prefer staffed phone consults, "exposed" brochure addressed to parents, and no incentives). A month of sustained and repeat multi-media campaign resulted in 330 hotline calls, 83 phone calls and only 17 subjects being tested (3 were positive) though many more intended to come. Cumulative effects and cost of various outreach efforts are being monitored

  8. Nontarget herbivory by a weed biocontrol insect is limited to spillover, reducing the chance of population-level impacts.

    Science.gov (United States)

    Catton, Haley A; Lalonde, Robert G; De Clerck-Floate, Rosemarie A

    2015-03-01

    Insects approved for classical biocontrol of weeds are often capable of using close relatives of their target weed for feeding, oviposition, or larval development, with reduced preference and performance. When nontarget herbivory occurs and is suspected to reduce survival, growth, or fecundity of individual plants, and insects are capable of reproducing on their nontarget host, characterization of spatial and temporal patterns of the occurrence and intensity of herbivory is valuable for predicting potential population-level effects. Here, we perform a novel post-release manipulative field experiment with a root-feeding biocontrol weevil, Mogulones crucifer, released in Canada to control the rangeland weed Cynoglossum officinale, to test for its ability to establish on the nontarget plant Hackelia micrantha. After Cynoglossum, M. crucifer exhibits its highest preference for and performance on Hackelia spp. We released M. crucifer on Canadian rangeland sites with naturally occurring populations of H. micrantha growing interspersed with the target weed or in the near absence of the target weed. Adult weevil feeding on surrounding plants was monitored for three summers after release (years 0, 1, and 2), and, subsequently, subsets of plants were destructively sampled to determine M. crucifer oviposition levels. Additional oviposition and larval development data were obtained from seven non-experimental sites where weevils were released zero, three, or four years earlier. M. crucifer was not detected on experimental sites without C. officinale after two years, and nontarget herbivory was restricted to rare, low-level spillover. Visible evidence of adult herbivory (i.e., scars on shoots) was associated with oviposition in 90% of targets but only 30% of nontarget plants. We infer, through ecological refuge theory, that nontarget population-level impacts from M. crucifer spillover are unlikely because of temporal, spatial, and probabilistic refuges from herbivory, and make

  9. Individual- and population-level effects of Odocoileus virginianus herbivory on the rare forest herb Scutellaria montana

    Directory of Open Access Journals (Sweden)

    Andrea R. Benson

    2014-08-01

    Full Text Available Odocoileus virginianus  (white-tailed deer grazing can impact rare plant species dramatically given their risk for local extirpation and extinction. To determine if O. virginianus management could aid conservation of federally threatened Scutellaria montana  (large-flowered skullcap, we conducted an exclosure experiment across a large occurrence of this rare species in Catoosa County, Georgia, USA. We aimed to: (1 quantify the effects of O. virginianus  grazing on S. montana  individuals, and (2 evaluate the potential of O. virginianus  to influence S. montana  populations. A lesser percentage of S. montana  individuals protected from O. virginianus  were grazed than plants accessible to grazers and additional protection from smaller grazers did not reduce grazing, suggesting that O. virginianus  primarily do graze S. montana. But grazing did not significantly influence S. montana  individuals as evidenced by changes in stem height or the number of leaves per plant assessed during two single growing seasons or across those growing seasons. At the population-level, grazing impacts were buffered by a lack of grazer preferences for specific plant life stages. Although mostly not significant, our findings are biologically interesting given the numerous ecological concerns associated with O. virginianus abundance, including their demonstrated and proposed impact on rare plants.

  10. Potential population-level effects of increased haulout-related mortality of Pacific walrus calves

    Science.gov (United States)

    Udevitz, Mark S.; Taylor, Rebecca L.; Garlich-Miller, Joel L.; Quakenbush, Lori T.; Snyder, Jonathan A.

    2013-01-01

    Availability of summer sea ice has been decreasing in the Chukchi Sea during recent decades, and increasing numbers of Pacific walruses have begun using coastal haulouts in late summer during years when sea ice retreats beyond the continental shelf. Calves and yearlings are particularly susceptible to being crushed during disturbance events that cause the herd to panic and stampede at these large haulouts, but the potential population-level effects of this mortality are unknown. We used recent harvest data, along with previous assumptions about demographic parameters for this population, to estimate female population size and structure in 2009 and project these numbers forward using a range of assumptions about future harvests and haulout-related mortality that might result from increased use of coastal haulouts during late summer. We found that if demographic parameters were held constant, the levels of harvest that occurred during 1990–2008 would have allowed the population to grow during that period. Our projections indicate, however, that an increase in haulout-related mortality affecting only calves has a greater effect on the population than an equivalent increase in harvest-related mortality distributed among all age classes. Therefore, disturbance-related mortality of calves at coastal haulouts may have relatively important population consequences.

  11. Host Genotype and Hypersensitive Reaction Influence Population Levels of Xanthomonas campestris pv. vitians in Lettuce.

    Science.gov (United States)

    Bull, Carolee T; Gebben, Samantha J; Goldman, Polly H; Trent, Mark; Hayes, Ryan J

    2015-03-01

    Dynamics of population sizes of Xanthomonas campestris pv. vitians inoculated onto or into lettuce leaves were monitored on susceptible and resistant cultivars. In general, population growth was greater for susceptible (Clemente, Salinas 88, Vista Verde) than resistant (Batavia Reine des Glaces, Iceberg, Little Gem) cultivars. When spray-inoculated or infiltrated, population levels of X. campestris pv. vitians were consistently significantly lower on Little Gem than on susceptible cultivars, while differences in the other resistant cultivars were not consistently statistically significant. Populations increased at an intermediate rate on cultivars Iceberg and Batavia Reine des Glaces. There were significant positive correlations between bacterial concentration applied and disease severity for all cultivars, but bacterial titer had a significantly greater influence on disease severity in the susceptible cultivars than in Little Gem and an intermediate influence in Iceberg and Batavia Reine des Glaces. Infiltration of X. campestris pv. vitians strains into leaves of Little Gem resulted in an incompatible reaction, whereas compatible reactions were observed in all other cultivars. It appears that the differences in the relationship between population dynamics for Little Gem and the other cultivars tested were due to the hypersensitive response in cultivar Little Gem. These findings have implications for disease management and lettuce breeding because X. campestris pv. vitians interacts differently with cultivars that differ for resistance mechanisms.

  12. Deterministic and stochastic population-level simulations of an artificial lac operon genetic network

    Directory of Open Access Journals (Sweden)

    Zygourakis Kyriacos

    2011-07-01

    Full Text Available Abstract Background The lac operon genetic switch is considered as a paradigm of genetic regulation. This system has a positive feedback loop due to the LacY permease boosting its own production by the facilitated transport of inducer into the cell and the subsequent de-repression of the lac operon genes. Previously, we have investigated the effect of stochasticity in an artificial lac operon network at the single cell level by comparing corresponding deterministic and stochastic kinetic models. Results This work focuses on the dynamics of cell populations by incorporating the above kinetic scheme into two Monte Carlo (MC simulation frameworks. The first MC framework assumes stochastic reaction occurrence, accounts for stochastic DNA duplication, division and partitioning and tracks all daughter cells to obtain the statistics of the entire cell population. In order to better understand how stochastic effects shape cell population distributions, we develop a second framework that assumes deterministic reaction dynamics. By comparing the predictions of the two frameworks, we conclude that stochasticity can create or destroy bimodality, and may enhance phenotypic heterogeneity. Conclusions Our results show how various sources of stochasticity act in synergy with the positive feedback architecture, thereby shaping the behavior at the cell population level. Further, the insights obtained from the present study allow us to construct simpler and less computationally intensive models that can closely approximate the dynamics of heterogeneous cell populations.

  13. Frequency-specific modulation of population-level frequency tuning in human auditory cortex

    Directory of Open Access Journals (Sweden)

    Roberts Larry E

    2009-01-01

    Full Text Available Abstract Background Under natural circumstances, attention plays an important role in extracting relevant auditory signals from simultaneously present, irrelevant noises. Excitatory and inhibitory neural activity, enhanced by attentional processes, seems to sharpen frequency tuning, contributing to improved auditory performance especially in noisy environments. In the present study, we investigated auditory magnetic fields in humans that were evoked by pure tones embedded in band-eliminated noises during two different stimulus sequencing conditions (constant vs. random under auditory focused attention by means of magnetoencephalography (MEG. Results In total, we used identical auditory stimuli between conditions, but presented them in a different order, thereby manipulating the neural processing and the auditory performance of the listeners. Constant stimulus sequencing blocks were characterized by the simultaneous presentation of pure tones of identical frequency with band-eliminated noises, whereas random sequencing blocks were characterized by the simultaneous presentation of pure tones of random frequencies and band-eliminated noises. We demonstrated that auditory evoked neural responses were larger in the constant sequencing compared to the random sequencing condition, particularly when the simultaneously presented noises contained narrow stop-bands. Conclusion The present study confirmed that population-level frequency tuning in human auditory cortex can be sharpened in a frequency-specific manner. This frequency-specific sharpening may contribute to improved auditory performance during detection and processing of relevant sound inputs characterized by specific frequency distributions in noisy environments.

  14. Current and future assays for identifying recent HIV infections at the population level.

    Science.gov (United States)

    Smoleń-Dzirba, Joanna; Wąsik, Tomasz J

    2011-05-01

    The precise diagnosis of recent human immunodeficiency virus (HIV) infection is crucial for estimating HIV incidence, defined as the number of new infections in a population, per person at risk, during a specified time period. Incidence assessment is considered to be a tool for surveillance, public health and research. Differentiating recent from long-term HIV infections is possible thanks to the evaluation of HIV-specific immune response development or viral markers measurement. Several methods that enable the recognition of recent HIV-1 infection with the use of a single blood specimen have been developed, and their value for use in population level studies has been demonstrated. However, they are still inadequate due to a variable window period and false recent rates among HIV clades and across populations. Application of these assays at an individual level is far more questionable because of person-to-person variability in the antibody response and the course of HIV infection, and because of the prospective regulatory approval requirements. In this article we review the principles and the limitations of the currently available major laboratory techniques that allow detection of recent HIV infection. The assays based on the alteration of serological parameters, as well as the newest method based on an increase of HIV genetic diversity with the progress of infection, are described.

  15. Developing methods to assess and predict the population level effects of environmental contaminants.

    Science.gov (United States)

    Emlen, J.M.; Springman, K.R.

    2007-01-01

    The field of ecological toxicity seems largely to have drifted away from what its title implies--assessing and predicting the ecological consequences of environmental contaminants--moving instead toward an emphasis on individual effects and physiologic case studies. This paper elucidates how a relatively new ecological methodology, interaction assessment (INTASS), could be useful in addressing the field's initial goals. Specifically, INTASS is a model platform and methodology, applicable across a broad array of taxa and habitat types, that can be used to construct population dynamics models from field data. Information on environmental contaminants and multiple stressors can be incorporated into these models in a form that bypasses the problems inherent in assessing uptake, chemical interactions in the environment, and synergistic effects in the organism. INTASS can, therefore, be used to evaluate the effects of contaminants and other stressors at the population level and to predict how changes in stressor levels or composition of contaminant mixtures, as well as various mitigation measures, might affect population dynamics.

  16. Genetic approaches to understanding the population-level impact of wind energy development on migratory bats

    Energy Technology Data Exchange (ETDEWEB)

    Vonhof, Maarten J. [Western Michigan Univ., Kalamazoo MI (United States); Russell, Amy L. [Grand Valley State Univ. Allendale, MI (United States)

    2013-09-30

    Documented fatalities of bats at wind turbines have raised serious concerns about the future impacts of increased wind power development on populations of migratory bat species. Yet there is little data on bat population sizes and trends to provide context for understanding the consequences of mortality due to wind power development. Using a large dataset of both nuclear and mitochondrial DNA variation for eastern red bats, we demonstrated that: 1) this species forms a single, panmictic population across their range with no evidence for the historical use of divergent migratory pathways by any portion of the population; 2) the effective size of this population is in the hundreds of thousands to millions; and 3) for large populations, genetic diversity measures and at least one coalescent method are insensitive to even very high rates of population decline over long time scales and until population size has become very small. Our data provide important context for understanding the population-level impacts of wind power development on affected bat species.

  17. Epithelial Label-Retaining Cells Are Absent during Tooth Cycling in Salmo salar and Polypterus senegalus.

    Directory of Open Access Journals (Sweden)

    Sam Vandenplas

    Full Text Available The Atlantic salmon (Salmo salar and African bichir (Polypterus senegalus are both actinopterygian fish species that continuously replace their teeth without the involvement of a successional dental lamina. Instead, they share the presence of a middle dental epithelium: an epithelial tier enclosed by inner and outer dental epithelium. It has been hypothesized that this tier could functionally substitute for a successional dental lamina and might be a potential niche to house epithelial stem cells involved in tooth cycling. Therefore, in this study we performed a BrdU pulse chase experiment on both species to (1 determine the localization and extent of proliferating cells in the dental epithelial layers, (2 describe cell dynamics and (3 investigate if label-retaining cells are present, suggestive for the putative presence of stem cells. Cells proliferate in the middle dental epithelium, outer dental epithelium and cervical loop at the lingual side of the dental organ to form a new tooth germ. Using long chase times, both in S. salar (eight weeks and P. senegalus (eight weeks and twelve weeks, we could not reveal the presence of label-retaining cells in the dental organ. Immunostaining of P. senegalus dental organs for the transcription factor Sox2, often used as a stem cell marker, labelled cells in the zone of outer dental epithelium which grades into the oral epithelium (ODE transition zone and the inner dental epithelium of a successor only. The location of Sox2 distribution does not provide evidence for epithelial stem cells in the dental organ and, more specifically, in the middle dental epithelium. Comparison of S. salar and P. senegalus reveals shared traits in tooth cycling and thus advances our understanding of the developmental mechanism that ensures lifelong replacement.

  18. Influence of Development and Dietary Phospholipid Content and Composition on Intestinal Transcriptome of Atlantic Salmon (Salmo salar.

    Directory of Open Access Journals (Sweden)

    Christian De Santis

    Full Text Available The inclusion of intact phospholipids in the diet is essential during larval development and can improve culture performance of many fish species. The effects of supplementation of dietary phospholipid from marine (krill or plant (soy lecithin sources were investigated in Atlantic salmon, Salmo salar. First feeding fry were fed diets containing either krill oil or soybean lecithin supplying phospholipid at 2.6%, 3.2%, 3.6% and 4.2% of diet. Fish were sampled at ~ 2.5 g (~1,990°day post fertilization, dpf and ~10 g (2,850°dpf. By comparison of the intestinal transcriptome in specifically chosen contrasts, it was determined that by 2,850°dpf fish possessed a profile that resembled that of mature and differentiated intestinal cell types with a number of changes specific to glycerophospholipid metabolism. It was previously shown that intact phospholipids and particularly phosphatidylcholine are essential during larval development and that this requirement is associated with the inability of enterocytes in young fry to endogenously synthesize sufficient phospholipid for the efficient export of dietary lipid. In the immature phase (~1,990°dpf, the dietary phospholipid content as well as its class composition impacted on several biochemical and morphological parameters including growth, but these differences were not associated with differences in intestinal transcriptomes. The results of this study have made an important contribution to our understanding of the mechanisms associated with lipid transport and phospholipid biosynthesis in early life stages of fish.

  19. Within-farm spread of infectious salmon anemia virus (ISAV) in Atlantic salmon Salmo salar farms in Chile.

    Science.gov (United States)

    Mardones, F O; Jansen, P A; Valdes-Donoso, P; Jarpa, M; Lyngstad, T M; Jimenez, D; Carpenter, T E; Perez, A M

    2013-09-24

    Spread of infectious salmon anemia virus (ISAV) at the cage level was quantified using a subset of data from 23 Atlantic salmon Salmo salar farms located in southern Chile. Data collected from official surveillance activities were systematically organized to obtain detailed information on infectious salmon anemia (ISA) outbreaks. Descriptive statistics for outbreak duration, proportion of infected fish, and time to secondary infection were calculated to quantify the magnitude of ISAV incursions. Linear and multiple failure time (MFT) regression models were used to determine factors associated with the cage-level reproduction number (Rc) and hazard rate (HR) for recurrent events, respectively. In addition, the Knox test was used to assess if cage-to-cage transmissions were clustered in space and time. Findings suggest that within farms, ISA outbreaks, on average, lasted 30 wk (median = 26 wk, 95% CI = 24 to 37 wk) and affected 57.3% (95% CI = 47.7 to 67.0%) of susceptible cages. The median time to secondarily diagnosed cages was 23 d. Occurrence of clinical ISAV outbreaks was significantly associated with increased Rc, whereas increased HR was significantly associated with clinical outbreaks and with a large number of fish. Spatio-temporal analysis failed to identify clustering of cage cases, suggesting that within-farm ISAV spread is independent of the spatial location of the cages. Results presented here will help to better understand ISAV transmission, to improve the design of surveillance programs in Chile and other regions in which salmon are intensively farmed, and to examine the economic impact of ISAV and related management strategies on various cost and demand shifting factors.

  20. Hatchery tank enrichment affects cortisol levels and shelter-seeking in Atlantic salmon (Salmo salar)

    DEFF Research Database (Denmark)

    Näslund, Joacim; Rosengren, Malin; Del Villar, Diego

    2013-01-01

    (Salmo salar) from three different environmental treatments (barren environment, plastic tube enrichment, and plastic shredding enrichment) with regard to plasma cortisol levels, shelter-seeking behaviour, and fin deterioration. Basal plasma cortisol levels were higher in barren-reared fish, indicating...... higher stress levels, while no differences were found in acute cortisol response after a 30 min confinement test. Shelter-seeking was higher in salmon reared in enriched tanks when tested alone, but not when tested in small groups. Barren-reared fish had higher levels of fin deterioration over winter...

  1. Genetic structure of European populations of Salmo salar L (Atlantic salmon) inferred from mitochondrial DNA

    DEFF Research Database (Denmark)

    Eg Nielsen, Einar; Hansen, Michael Møller; Loeschcke, V.

    1996-01-01

    The genetic relationships between the only natural population of Atlantic salmon (Salmo salar L.) in Denmark and seven other European salmon populations were studied using RFLP analysis of PCR amplified mitochondrial DNA segments. Six different haplotypes were detected by restriction enzyme...... analyses of the NADH dehydrogenase 1 segment, employing four endonucleases. Significant genetic differentiation was observed among populations. A hierarchical analysis of the distribution of the mtDNA variability revealed that only a small part was distributed among geographical groups within the study...

  2. Differential effects of mercurial compounds on the electroolfactogram (EOG) of salmon (Salmo salar L.)

    DEFF Research Database (Denmark)

    Baatrup, E; Døving, K B; Winberg, S

    1991-01-01

    The effects on the salmon (Salmo salar L.) electroolfactogram (EOG) of the two mercurials, mercuric chloride (HgCl2) and methylmercuric chloride (CH3HgCl), were studied. The EOG responses were evoked by stimulating the olfactory epithelium with 340 microM L-alanine for 10 sec every second minute...... of this study demonstrate the vulnerability of the olfactory receptor function in fish to mercury exposure. Also, they show the very different effects of inorganic and organic mercurials upon the EOG. Udgivelsesdato: 1990-Dec...

  3. Expansion of the National Salt Reduction Initiative: A Mathematical Model of Benefits and Risks of Population-Level Sodium Reduction.

    Science.gov (United States)

    Choi, Sung Eun; Brandeau, Margaret L; Basu, Sanjay

    2016-01-01

    The National Salt Reduction Initiative, in which food producers agree to lower sodium to levels deemed feasible for different foods, is expected to significantly reduce sodium intake if expanded to a large sector of food manufacturers. Given recent data on the relationship between sodium intake, hypertension, and associated cardiovascular disease at a population level, we sought to examine risks and benefits of the program. To estimate the impact of further expanding the initiative on hypertension, myocardial infarction (MI) and stroke incidence, and related mortality, given food consumption patterns across the United States, we developed and validated a stochastic microsimulation model of hypertension, MI, and stroke morbidity and mortality, using data from food producers on sodium reduction among foods, linked to 24-hour dietary recalls, blood pressure, and cardiovascular histories from the National Health and Nutrition Examination Survey. Expansion of the initiative to ensure all restaurants and manufacturers reach agreed-upon sodium targets would be expected to avert from 0.9 to 3.0 MIs (a 1.6%-5.4% reduction) and 0.5 to 2.8 strokes (a 1.1%-6.2% reduction) per 10,000 Americans per year over the next decade, after incorporating consumption patterns and variations in the effect of sodium reduction on blood pressure among different demographic groups. Even high levels of consumer addition of table salt or substitution among food categories would be unlikely to neutralize this benefit. However, if recent epidemiological associations between very low sodium and increased mortality are causal, then older women may be at risk of increased mortality from excessively low sodium intake. An expanded National Salt Reduction Initiative is likely to significantly reduce hypertension and hypertension-related cardiovascular morbidity but may be accompanied by potential risks to older women. © The Author(s) 2015.

  4. The projected burden of osteoarthritis and rheumatoid arthritis in Australia: A population-level analysis.

    Science.gov (United States)

    Ackerman, Ilana N; Pratt, Clare; Gorelik, Alexandra; Liew, Danny

    2017-09-12

    To forecast the prevalence and direct healthcare costs of osteoarthritis (OA) and rheumatoid arthritis (RA) in Australia to the year 2030. An epidemiological model of the Australian population was developed. Data on the national prevalence of OA and RA were obtained from the Australian Bureau of Statistics (ABS) 2014-2015 National Health Survey. Future prevalence was estimated using ABS population projections for 2020, 2025 and 2030. Available government data on direct healthcare expenditure for OA and RA were modelled to forecast costs (in AUD) for the years 2020, 2025 and 2030, from the perspective of the Australian public healthcare system. The number of people with OA is expected to increase nationally from almost 2.2 million in 2015 to almost 3.1 million Australians in 2030. The number of people with RA is projected to increase from 422,309 in 2015 to 579,915 in 2030. Healthcare costs for OA were estimated to be over $2.1 billion in 2015; by the year 2030, these are forecast to exceed $2.9 billion ($970 for every person with the condition). Healthcare costs for RA were estimated to be over $550 million in 2015, including $273 million spent on biological disease-modifying anti-rheumatic drugs. Healthcare costs for RA are projected to rise to over $755 million by the year 2030. OA and RA are costly conditions that will impose an increasing healthcare burden at the population level. These projections provide tangible data that can be utilised to map future health service provision to expected need. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  5. Present limits to heat-adaptability in corals and population-level responses to climate extremes.

    Directory of Open Access Journals (Sweden)

    Bernhard M Riegl

    Full Text Available Climate change scenarios suggest an increase in tropical ocean temperature by 1-3°C by 2099, potentially killing many coral reefs. But Arabian/Persian Gulf corals already exist in this future thermal environment predicted for most tropical reefs and survived severe bleaching in 2010, one of the hottest years on record. Exposure to 33-35°C was on average twice as long as in non-bleaching years. Gulf corals bleached after exposure to temperatures above 34°C for a total of 8 weeks of which 3 weeks were above 35°C. This is more heat than any other corals can survive, providing an insight into the present limits of holobiont adaptation. We show that average temperatures as well as heat-waves in the Gulf have been increasing, that coral population levels will fluctuate strongly, and reef-building capability will be compromised. This, in combination with ocean acidification and significant local threats posed by rampant coastal development puts even these most heat-adapted corals at risk. WWF considers the Gulf ecoregion as "critically endangered". We argue here that Gulf corals should be considered for assisted migration to the tropical Indo-Pacific. This would have the double benefit of avoiding local extinction of the world's most heat-adapted holobionts while at the same time introducing their genetic information to populations naïve to such extremes, potentially assisting their survival. Thus, the heat-adaptation acquired by Gulf corals over 6 k, could benefit tropical Indo-Pacific corals who have <100 y until they will experience a similarly harsh climate. Population models suggest that the heat-adapted corals could become dominant on tropical reefs within ∼20 years.

  6. Quantitative assessment of the role of male circumcision in HIV epidemiology at the population level.

    Science.gov (United States)

    Alsallaq, Ramzi A; Cash, Brianna; Weiss, Helen A; Longini, Ira M; Omer, Saad B; Wawer, Maria J; Gray, Ronald H; Abu-Raddad, Laith J

    2009-09-01

    Three recent randomized trials have shown that male circumcision (circumcision) reduces HIV incidence in heterosexual men by about 60%. Mathematical models are needed to assess the historical role of circumcision in the observed disparate levels of prevalence in sub-Saharan Africa and to translate these findings into estimates of the population-level impact of circumcision on HIV prevalence. A deterministic compartmental model of HIV dynamics with circumcision was parameterized by empirical data from the Rakai, Masaka, and Four-City studies. Circumcision was found to account for about two-thirds of the differential HIV prevalence between West Africa and East and Southern Africa. We found that in Kisumu, Kenya, and in Rakai, Uganda, universal circumcision implemented in 2008 would reduce HIV prevalence by 19% and 14%, respectively, by 2020. In Kisumu, a setting with high HIV prevalence, about 6 circumcisions would be needed for each infection averted while in Rakai, 11 circumcisions would be needed. Females will also benefit from circumcision with a substantial reduction in prevalence of about 8% in Kisumu and 4% in Rakai within a few years of universal circumcision. The beneficial impact of circumcision for both males and females will not be undermined by risk behavior compensation unless the increase in risk behavior is in excess of 30%. The effectiveness of circumcision as an intervention is maximized by universal circumcision within 2-3 years. In West Africa, circumcision may have "quarantined" the spread of HIV by limiting sustainable transmission to within high risk groups and bridge populations. Our findings indicate that circumcision is an effective intervention in both high and intermediate HIV prevalence settings. Circumcision coverage should be expanded as soon as possible to optimize the epidemiological impact.

  7. Ecological feedbacks can reduce population-level efficacy of wildlife fertility control

    Science.gov (United States)

    Ransom, Jason I.; Powers, Jenny G.; Hobbs, N. Thompson; Baker, Dan L.

    2014-01-01

    1. Anthropogenic stress on natural systems, particularly the fragmentation of landscapes and the extirpation of predators from food webs, has intensified the need to regulate abundance of wildlife populations with management. Controlling population growth using fertility control has been considered for almost four decades, but nearly all research has focused on understanding effects of fertility control agents on individual animals. Questions about the efficacy of fertility control as a way to control populations remain largely unanswered. 2. Collateral consequences of contraception can produce unexpected changes in birth rates, survival, immigration and emigration that may reduce the effectiveness of regulating animal abundance. The magnitude and frequency of such effects vary with species-specific social and reproductive systems, as well as connectivity of populations. Developing models that incorporate static demographic parameters from populations not controlled by contraception may bias predictions of fertility control efficacy. 3. Many population-level studies demonstrate that changes in survival and immigration induced by fertility control can compensate for the reduction in births caused by contraception. The most successful cases of regulating populations using fertility control come from applications of contraceptives to small, closed populations of gregarious and easily accessed species. 4. Fertility control can result in artificial selection pressures on the population and may lead to long-term unintentional genetic consequences. The magnitude of such selection is dependent on individual heritability and behavioural traits, as well as environmental variation. 5. Synthesis and applications. Understanding species' life-history strategies, biology, behavioural ecology and ecological context is critical to developing realistic expectations of regulating populations using fertility control. Before time, effort and funding are invested in wildlife

  8. Cost-effectiveness of population-level physical activity interventions: a systematic review.

    Science.gov (United States)

    Laine, Johanna; Kuvaja-Köllner, Virpi; Pietilä, Eija; Koivuneva, Mikko; Valtonen, Hannu; Kankaanpää, Eila

    2014-01-01

    This systematic review synthesizes the evidence on the cost-effectiveness of population-level interventions to promote physical activity. A systematic literature search was conducted between May and August 2013 in four databases: PubMed, Scopus, Web of Science, and SPORTDiscus. Only primary and preventive interventions aimed at promoting and maintaining physical activity in wide population groups were included. An economic evaluation of both effectiveness and cost was required. Secondary interventions and interventions targeting selected population groups or focusing on single individuals were excluded. Interventions were searched for in six different categories: (1) environment, (2) built environment, (3) sports clubs and enhanced access, (4) schools, (5) mass media and community-based, and (6) workplace. The systematic search yielded 2058 articles, of which 10 articles met the selection criteria. The costs of interventions were converted to costs per person per day in 2012 U.S. dollars. The physical activity results were calculated as metabolic equivalent of task hours (MET-hours, or MET-h) gained per person per day. Cost-effectiveness ratios were presented as dollars per MET-hours gained. The intervention scale and the budget impact of interventions were taken into account. The most efficient interventions to increase physical activity were community rail-trails ($.006/MET-h), pedometers ($.014/MET-h), and school health education programs ($.056/MET-h). Improving opportunities for walking and biking seems to increase physical activity cost-effectively. However, it is necessary to be careful in generalizing the results because of the small number of studies. This review provides important information for decision makers.

  9. Integrating Traditional and Evolutionary Knowledge in Biodiversity Conservation: a Population Level Case Study

    Directory of Open Access Journals (Sweden)

    Dylan J. Fraser

    2006-12-01

    Full Text Available Despite their dual importance in the assessment of endangered/threatened species, there have been few attempts to integrate traditional ecological knowledge (TEK and evolutionary biology knowledge (EBK at the population level. We contrasted long-term aboriginal TEK with previously obtained EBK in the context of seasonal migratory habits and population biology of a salmonid fish, brook charr, (Salvelinus fontinalis inhabiting a large, remote postglacial lake. Compilation of TEK spanning four decades involved analytical workshops, semidirective interviews, and collaborative fieldwork with local aboriginal informants and fishing guides. We found that TEK complemented EBK of brook charr by providing concordant and additional information about (1 population viability; (2 breeding areas and migration patterns of divergent populations; and (3 the behavioral ecology of populations within feeding areas; all of which may ultimately affect the maintenance of population diversity. Aboriginal concerns related to human pressures on this species, not revealed by EBK, also help to focus future conservation initiatives for divergent populations and to encourage restoration of traditional fishing practices. However, relative to EBK, the relevance of TEK to salmonid biodiversity conservation was evident mainly at a smaller spatial scale, for example, that of individual rivers occupied by populations or certain lake sectors. Nevertheless, EBK was only collected over a 4-yr period, so TEK provided an essential long-term temporal window to evaluate population differences and persistence. We concluded that, despite different conceptual underpinnings, spatially and temporally varying TEK and EBK both contribute to the knowledge base required to achieve sustainability and effective biodiversity conservation planning for a given species. Such integration may be particularly relevant in many isolated regions, where intraspecific diversity can go unrecognized due to sparse

  10. The vitamin D receptor and its ligand 1α,25-dihydroxyvitamin D3 in Atlantic salmon (Salmo salar)

    NARCIS (Netherlands)

    Lock, E.J.; Ornsrud, R.; Aksnes, L.; Spanings, F.A.; Waagbo, R.; Flik, G.

    2007-01-01

    Seaward migration of Salmo salar is preceded by preparatory physiological adaptations (parr-smolt transformation) to allow for a switch from freshwater (FW) to seawater (SW), which also means a switch in ambient calcium from hypocalcic (<1 mM Ca(2+)) to the plasma (~1.25 mM Ca(2+)) and to strongly

  11. Systemic granuloma observed in Atlantic salmon Salmo salar raised to market size in a freshwater recirculation aquaculture system

    Science.gov (United States)

    Systemic granuloma was observed in sampled adult Atlantic salmon Salmo salar raised to harvest size in a freshwater recirculation aquaculture system. The prevalence of this condition was estimated at 10-20% of the population, with affected individuals grossly demonstrating pathology in varying degre...

  12. Vaccination improves survival of Baltic salmon ( Salmo salar ) smolts in delayed release sea ranching (net-pen period)

    DEFF Research Database (Denmark)

    Buchmann, Kurt; Dalsgaard, Inger; Nielsen, Michael Engelbrecht

    1997-01-01

    Baltic salmon (Salmo salar) of the Finnish Iijoki stock were hatched and reared in freshwater in a salmon hatchery on the Danish island of Bornholm in the Baltic sea. Salmon parr were divided in three groups each comprising 22 000 fish. One group was vaccinated by intraperitoneal injection...

  13. Population-level effects and recovery of aquatic invertebrates after multiple applications of an insecticide.

    Science.gov (United States)

    Dohmen, G Peter; Preuss, Thomas G; Hamer, Mick; Galic, Nika; Strauss, Tido; van den Brink, Paul J; De Laender, Frederik; Bopp, Stephanie

    2016-01-01

    Standard risk assessment of plant protection products (PPP) combines "worst-case" exposure scenarios with effect thresholds using assessment (safety) factors to account for uncertainties. If needed, risks can be addressed applying more realistic conditions at higher tiers, which refine exposure and/or effect assessments using additional data. However, it is not possible to investigate the wide range of potential scenarios experimentally. In contrast, ecotoxicological mechanistic effect models do allow for addressing a multitude of scenarios. Furthermore, they may aid the interpretation of experiments such as mesocosm studies, allowing extrapolation to conditions not covered in experiments. Here, we explore how to use mechanistic effect models in the aquatic risk assessment of a model insecticide (Modelmethrin), applied several times per season but rapidly dissipating between applications. The case study focuses on potential effects on aquatic arthropods, the most sensitive group for this substance. The models provide information on the impact of a number of short exposure pulses on sensitive and/or vulnerable populations and, when impacted, assess recovery. The species to model were selected based on their sensitivity in laboratory and field (mesocosm) studies. The general unified threshold model for survival (GUTS) model, which describes the toxicokinetics and toxicodynamics of chemicals in individuals, was linked to 3 individual-based models (IBM), translating individual survival of sensitive organisms into population-level effects. The impact of pulsed insecticide exposures on populations were modeled using the spatially explicit IBM metapopulation model for assessing spatial and temporal effects of pesticides (MASTEP) for Gammarus pulex, the Chaoborus IBM for populations of Chaoborus crystallinus, and the "IdamP" model for populations of Daphnia magna. The different models were able to predict the potential effects of Modelmethrin applications to key arthropod

  14. Taxonomic structure and population level of colon microbial contents in white rats with experimental thyrotoxicosis

    Directory of Open Access Journals (Sweden)

    L.I. Sydorchuk

    2017-08-01

    Full Text Available Background. Production of numerous biologically active compounds and their metabolites by intestinal microflora, interaction with the immune and other systems is of great importance while studying its changes in various diseases, one of which is thyrotoxicosis. So, the purpose of this study was to determine the severity of intestine microbioma disorder in white rats with experimental thyrotoxicosis (ET. Materials and methods. Studies were carried out on 25 mature male white rats (15 — control group, 10 — research group. ET was simulated by intragastric administration of L-thyroxine for 14 days. Under sterile conditions a laparotomy was performed, a section (2–3 cm of the large intestine with its contents was taken. Sterile 0.9% NaCl solution was added to the content. Series of ten-fold dilutions with a concentration of the initial mixture of 10–2 to 10–11 was prepared. From each test tube 0.01 ml was seeded on solid nutrient media with subsequent isolation and identification of microbes according to morphological, tinctorial, cultural and biochemical properties. Results. The results of the study demonstrated that in ET animals the main microbioma is represented by bacteria Bifidobacterium, Lactobacillus, Bacteroides, and also opportunistic enterobacteria (Escherichia, Proteus, Klebsiella, peptococcus, staphylococci and clostridia. This is accompanied by the elimination of Peptostreptococcus, Enterococcus from bacterial biotope and the contamination of K. oxytoca and staphylococci. There was a pronounced deficit of bifidobacteria by 42.81 %, lactobacillus by 22.57 %, normal intestinal bacillus by 16.48 %. By the population level, the coefficient of quantitative dominance and the significance factor, the leading place is occupied by bacteroids, role of which is increased by 21.72 %, and lactobacillus role decreases by 39.31 %, bifidobacteria decreases by 51.48 % and E. coli decreases by 57.49 %. In this case, the role of peptococcus 3

  15. Population-Level Prediction of Type 2 Diabetes From Claims Data and Analysis of Risk Factors.

    Science.gov (United States)

    Razavian, Narges; Blecker, Saul; Schmidt, Ann Marie; Smith-McLallen, Aaron; Nigam, Somesh; Sontag, David

    2015-12-01

    We present a new approach to population health, in which data-driven predictive models are learned for outcomes such as type 2 diabetes. Our approach enables risk assessment from readily available electronic claims data on large populations, without additional screening cost. Proposed model uncovers early and late-stage risk factors. Using administrative claims, pharmacy records, healthcare utilization, and laboratory results of 4.1 million individuals between 2005 and 2009, an initial set of 42,000 variables were derived that together describe the full health status and history of every individual. Machine learning was then used to methodically enhance predictive variable set and fit models predicting onset of type 2 diabetes in 2009-2011, 2010-2012, and 2011-2013. We compared the enhanced model with a parsimonious model consisting of known diabetes risk factors in a real-world environment, where missing values are common and prevalent. Furthermore, we analyzed novel and known risk factors emerging from the model at different age groups at different stages before the onset. Parsimonious model using 21 classic diabetes risk factors resulted in area under ROC curve (AUC) of 0.75 for diabetes prediction within a 2-year window following the baseline. The enhanced model increased the AUC to 0.80, with about 900 variables selected as predictive (p predicting diabetes onset 1-3 years and 2-4 years after baseline. The enhanced model improved positive predictive value by at least 50% and identified novel surrogate risk factors for type 2 diabetes, such as chronic liver disease (odds ratio [OR] 3.71), high alanine aminotransferase (OR 2.26), esophageal reflux (OR 1.85), and history of acute bronchitis (OR 1.45). Liver risk factors emerge later in the process of diabetes development compared with obesity-related factors such as hypertension and high hemoglobin A1c. In conclusion, population-level risk prediction for type 2 diabetes using readily available administrative

  16. Stressed mothers - troubled offspring: a study of behavioural maternal effects in farmed Salmo salar.

    Science.gov (United States)

    Eriksen, M S; Faerevik, G; Kittilsen, S; McCormick, M I; Damsgård, B; Braithwaite, V A; Braastad, B O; Bakken, M

    2011-09-01

    Mature female Atlantic salmon Salmo salar were given intraperitoneal cortisol implants 1 week prior to stripping to examine the influence of simulated maternal stress on offspring boldness and social dominance. Behavioural tests originally designed to investigate stress responsiveness and coping styles in salmonids (i.e. feeding in isolation, dominance tests and acute confinement) were carried out on the offspring 1·5 years after hatching. In the feeding test, there were no differences between the two treatment groups in total feeding score or number of pellets eaten, but offspring from the cortisol-implanted females made more unsuccessful feeding attempts than offspring from control females. In dominance tests, there was no difference between controls and cortisol-treated fish regarding propensity to become socially dominant. A higher proportion of individuals with bite marks, however, was observed in the cortisol group when compared to controls. Cortisol-treated offspring that gained dominant rank in the dominance tests performed more aggressive acts after stable dominance-subordinate relationships were established compared to control winners. During acute confinement stress, offspring from cortisol-implanted females showed a reduction in the proportion of time they were moving compared to the controls. These results indicate that the maternal endocrine state at spawning affects several aspects of progeny behaviour potentially related to subsequent success and survival in farmed S. salar. © 2011 The Authors. Journal of Fish Biology © 2011 The Fisheries Society of the British Isles.

  17. Estimating the need for palliative care at the population level: A cross-national study in 12 countries.

    Science.gov (United States)

    Morin, Lucas; Aubry, Régis; Frova, Luisa; MacLeod, Roderick; Wilson, Donna M; Loucka, Martin; Csikos, Agnes; Ruiz-Ramos, Miguel; Cardenas-Turanzas, Marylou; Rhee, YongJoo; Teno, Joan; Öhlén, Joakim; Deliens, Luc; Houttekier, Dirk; Cohen, Joachim

    2017-06-01

    To implement the appropriate services and develop adequate interventions, detailed estimates of the needs for palliative care in the population are needed. To estimate the proportion of decedents potentially in need of palliative care across 12 European and non-European countries. This is a cross-sectional study using death certificate data. All adults (⩾18 years) who died in 2008 in Belgium, Czech Republic, France, Hungary, Italy, Spain (Andalusia, 2010), Sweden, Canada, the United States (2007), Korea, Mexico, and New Zealand ( N = 4,908,114). Underlying causes of death were used to apply three estimation methods developed by Rosenwax et al., the French National Observatory on End-of-Life Care, and Murtagh et al., respectively. The proportion of individuals who died from diseases that indicate palliative care needs at the end of life ranged from 38% to 74%. We found important cross-country variation: the population potentially in need of palliative care was lower in Mexico (24%-58%) than in the United States (41%-76%) and varied from 31%-83% in Hungary to 42%-79% in Spain. Irrespective of the estimation methods, female sex and higher age were independently associated with the likelihood of being in need of palliative care near the end of life. Home and nursing home were the two places of deaths with the highest prevalence of palliative care needs. These estimations of the size of the population potentially in need of palliative care provide robust indications of the challenge countries are facing if they want to seriously address palliative care needs at the population level.

  18. Opioid Dose Reduction in a VA Health Care System--Implementation of a Primary Care Population-Level Initiative.

    Science.gov (United States)

    Westanmo, Anders; Marshall, Peter; Jones, Elzie; Burns, Kevin; Krebs, Erin E

    2015-05-01

    To describe processes and outcomes of a health system quality improvement initiative designed to reduce opioid-related harms. The initiative was a primary care population-level intervention to reduce high-dose opioid prescribing, which was locally defined as >200 morphine-equivalent mg (MED) daily. We describe the implementation process and report prescribing rates and primary care provider (PCP) attitudes and beliefs before and after implementation. A VA health care system comprising one large, urban teaching hospital and 11 outpatient clinics in surrounding suburban and rural locations. All patients who received any prescription from the outpatient pharmacy (unique pharmacy patients) were included in the population. PCPs at the main hospital were surveyed. Prescribing outcomes were determined from merged VA databases by examining rates of opioid dispensing within 90-day time windows before and after implementation. PCP beliefs and attitudes were evaluated with preimplementation and postimplementation surveys. Following implementation, the number of patients prescribed >200 MED daily decreased from 342 (0.65% of unique pharmacy patients) to 65 (0.12%). Overall, the number of unique pharmacy patients who received at least one opioid prescription within 90 days decreased from 6,942 (13.7%) on April 1, 2011 to 5,981 (11.0%) on October 1, 2014 (13.8% decrease). Most PCPs agreed it was reasonable for the medical center to set a 200 MED limit (76% at baseline and 87% at follow up). Opioid Safety Initiative implementation was associated with a substantial reduction in high-dose opioid prescribing. Factors that contributed to initiative success included leadership support and active clinical pharmacy engagement. Wiley Periodicals, Inc.

  19. Community-based population-level interventions for promoting child oral health.

    Science.gov (United States)

    de Silva, Andrea M; Hegde, Shalika; Akudo Nwagbara, Bridget; Calache, Hanny; Gussy, Mark G; Nasser, Mona; Morrice, Hannah R; Riggs, Elisha; Leong, Pamela M; Meyenn, Lisa K; Yousefi-Nooraie, Reza

    2016-09-15

    Dental caries and gingival and periodontal disease are commonly occurring, preventable chronic conditions. Even though much is known about how to treat oral disease, currently we do not know which community-based population-level interventions are most effective and equitable in preventing poor oral health. Primary • To determine the effectiveness of community-based population-level oral health promotion interventions in preventing dental caries and gingival and periodontal disease among children from birth to 18 years of age. Secondary • To determine the most effective types of interventions (environmental, social, community and multi-component) and guiding theoretical frameworks.• To identify interventions that reduce inequality in oral health outcomes.• To examine the influence of context in the design, delivery and outcomes of interventions. We searched the following databases from January 1996 to April 2014: MEDLINE, Embase, the Cochrane Central Register of Controlled Trials (CENTRAL), the Cumulative Index to Nursing and Allied Health Literature (CINAHL), the Education Resource Information Center (ERIC), BIOSIS Previews, Web of Science, the Database of Abstracts of Reviews of Effects (DARE), ScienceDirect, Sociological Abstracts, Social Science Citation Index, PsycINFO, SCOPUS, ProQuest Dissertations & Theses and Conference Proceedings Citation Index - Science. Included studies were individual- and cluster-randomised controlled trials (RCTs), controlled before-and-after studies and quasi-experimental and interrupted time series. To be included, interventions had to target the primary outcomes: dental caries (measured as decayed, missing and filled deciduous teeth/surfaces, dmft/s; Decayed, Missing and Filled permanent teeth/surfaces, DMFT/S) and gingival or periodontal disease among children from birth to 18 years of age. Studies had to report on one or more of the primary outcomes at baseline and post intervention, or had to provide change scores for

  20. WITHDRAWN: Community-based population-level interventions for promoting child oral health.

    Science.gov (United States)

    de Silva, Andrea M; Hegde, Shalika; Akudo Nwagbara, Bridget; Calache, Hanny; Gussy, Mark G; Nasser, Mona; Morrice, Hannah R; Riggs, Elisha; Leong, Pamela M; Meyenn, Lisa K; Yousefi-Nooraie, Reza

    2016-12-22

    Dental caries and gingival and periodontal disease are commonly occurring, preventable chronic conditions. Even though much is known about how to treat oral disease, currently we do not know which community-based population-level interventions are most effective and equitable in preventing poor oral health. Primary • To determine the effectiveness of community-based population-level oral health promotion interventions in preventing dental caries and gingival and periodontal disease among children from birth to 18 years of age. Secondary • To determine the most effective types of interventions (environmental, social, community and multi-component) and guiding theoretical frameworks.• To identify interventions that reduce inequality in oral health outcomes.• To examine the influence of context in the design, delivery and outcomes of interventions. We searched the following databases from January 1996 to April 2014: MEDLINE, Embase, the Cochrane Central Register of Controlled Trials (CENTRAL), the Cumulative Index to Nursing and Allied Health Literature (CINAHL), the Education Resource Information Center (ERIC), BIOSIS Previews, Web of Science, the Database of Abstracts of Reviews of Effects (DARE), ScienceDirect, Sociological Abstracts, Social Science Citation Index, PsycINFO, SCOPUS, ProQuest Dissertations & Theses and Conference Proceedings Citation Index - Science. Included studies were individual- and cluster-randomised controlled trials (RCTs), controlled before-and-after studies and quasi-experimental and interrupted time series. To be included, interventions had to target the primary outcomes: dental caries (measured as decayed, missing and filled deciduous teeth/surfaces, dmft/s; Decayed, Missing and Filled permanent teeth/surfaces, DMFT/S) and gingival or periodontal disease among children from birth to 18 years of age. Studies had to report on one or more of the primary outcomes at baseline and post intervention, or had to provide change scores for

  1. Coping with unpredictability: dopaminergic and neurotrophic responses to omission of expected reward in Atlantic salmon (Salmo salar L..

    Directory of Open Access Journals (Sweden)

    Marco A Vindas

    Full Text Available Comparative studies are imperative for understanding the evolution of adaptive neurobiological processes such as neural plasticity, cognition, and emotion. Previously we have reported that prolonged omission of expected rewards (OER, or 'frustrative nonreward' causes increased aggression in Atlantic salmon (Salmo salar. Here we report changes in brain monoaminergic activity and relative abundance of brain derived neurotrophic factor (BDNF and dopamine receptor mRNA transcripts in the same paradigm. Groups of fish were initially conditioned to associate a flashing light with feeding. Subsequently, the expected food reward was delayed for 30 minutes during two out of three meals per day in the OER treatment, while the previously established routine was maintained in control groups. After 8 days there was no effect of OER on baseline brain stem serotonin (5-HT or dopamine (DA activity. Subsequent exposure to acute confinement stress led to increased plasma cortisol and elevated turnover of brain stem DA and 5-HT in all animals. The DA response was potentiated and DA receptor 1 (D1 mRNA abundance was reduced in the OER-exposed fish, indicating a sensitization of the DA system. In addition OER suppressed abundance of BDNF in the telencephalon of non-stressed fish. Regardless of OER treatment, a strong positive correlation between BDNF and D1 mRNA abundance was seen in non-stressed fish. This correlation was disrupted by acute stress, and replaced by a negative correlation between BDNF abundance and plasma cortisol concentration. These observations indicate a conserved link between DA, neurotrophin regulation, and corticosteroid-signaling pathways. The results also emphasize how fish models can be important tools in the study of neural plasticity and responsiveness to environmental unpredictability.

  2. Uptake and effects of uranium nanoparticles on early life stage of Atlantic salmon (Salmo salar)

    Energy Technology Data Exchange (ETDEWEB)

    Kleiven, M.; Teien, H.C.; Lind, O.C.; Vaa Johnsen, I.; Oughton, D.; Salbu, B. [Norwegian University of Life Sciences (Norway)

    2014-07-01

    Nanotechnology has been, and still is, a major scientific and economic growth area. Over the last decade, the awareness of nano-material as a potential human and environmental hazard has increased dramatically. Being a naturally occurring radionuclide, as well as the major fuel material used in nuclear energy power plants, many sources of uranium (U) are found in the environment. Uranium nanoparticles (NPs) can occur naturally (i.e., colloidal species), as incidental anthropogenic sources (e.g., debris from depleted U weapons and fuel manufacture and reprocessing), or can be intentionally synthesized for use as catalysts. Studies on environmental aspects of U NPs are rather scarce in literature. Thus, the focus of the present work was to obtain information on uptake and potential effects of U NPs on early life stage of Atlantic salmon (Salmo salar). Eggs of Atlantic salmon were exposed to two types of U NPs, U{sub 3}O{sub 8} and UO{sub 2}, as well as to uranyl ions, in natural soft water (TOC 4.5 mg/L) at pH 7.2. Two U NP exposure experiments during fertilization were performed, both with exposure for 24 h. The exposure period was followed by a depuration period in uncontaminated water (7 and 69 days of depuration, respectively). Exposure solutions were subject to a suite of techniques to characterize the exposure during the experiment. Dissection of eggs was performed prior to the determination of U to distinguish between U associated to the shell and U in the egg fluid. Results showed that U was highest in eggs exposed to uranyl, especially during the stage of swelling, and the uptake into the eggs increased with exposure time. The uptake of U in eggs exposed to U NPs was only minor, and may be due to U ions in exposure solutions or released from U-NPs, rather than an actual U NP uptake. However, on the surface of eggs exposed to U NPs large amounts of U NPs were deposited during the experimental duration period, potentially posing a risk over time. There were no

  3. Population-level impact and herd effects following human papillomavirus vaccination programmes: a systematic review and meta-analysis.

    Science.gov (United States)

    Drolet, Mélanie; Bénard, Élodie; Boily, Marie-Claude; Ali, Hammad; Baandrup, Louise; Bauer, Heidi; Beddows, Simon; Brisson, Jacques; Brotherton, Julia M L; Cummings, Teresa; Donovan, Basil; Fairley, Christopher K; Flagg, Elaine W; Johnson, Anne M; Kahn, Jessica A; Kavanagh, Kimberley; Kjaer, Susanne K; Kliewer, Erich V; Lemieux-Mellouki, Philippe; Markowitz, Lauri; Mboup, Aminata; Mesher, David; Niccolai, Linda; Oliphant, Jeannie; Pollock, Kevin G; Soldan, Kate; Sonnenberg, Pam; Tabrizi, Sepehr N; Tanton, Clare; Brisson, Marc

    2015-05-01

    Human papillomavirus (HPV) vaccination programmes were first implemented in several countries worldwide in 2007. We did a systematic review and meta-analysis to assess the population-level consequences and herd effects after female HPV vaccination programmes, to verify whether or not the high efficacy reported in randomised controlled clinical trials are materialising in real-world situations. We searched the Medline and Embase databases (between Jan 1, 2007 and Feb 28, 2014) and conference abstracts for time-trend studies that analysed changes, between the pre-vaccination and post-vaccination periods, in the incidence or prevalence of at least one HPV-related endpoint: HPV infection, anogenital warts, and high-grade cervical lesions. We used random-effects models to derive pooled relative risk (RR) estimates. We stratified all analyses by age and sex. We did subgroup analyses by comparing studies according to vaccine type, vaccination coverage, and years since implementation of the vaccination programme. We assessed heterogeneity across studies using I(2) and χ(2) statistics and we did trends analysis to examine the dose-response association between HPV vaccination coverage and each study effect measure. We identified 20 eligible studies, which were all undertaken in nine high-income countries and represent more than 140 million person-years of follow-up. In countries with female vaccination coverage of at least 50%, HPV type 16 and 18 infections decreased significantly between the pre-vaccination and post-vaccination periods by 68% (RR 0·32, 95% CI 0·19-0·52) and anogenital warts decreased significantly by 61% (0·39, 0·22-0·71) in girls 13-19 years of age. Significant reductions were also recorded in HPV types 31, 33, and 45 in this age group of girls (RR 0·72, 95% CI 0·54-0·96), which suggests cross-protection. Additionally, significant reductions in anogenital warts were also reported in boys younger than 20 years of age (0·66 [95% CI 0·47-0·91

  4. Population-level impact and herd effects following human papillomavirus vaccination programmes: a systematic review and meta-analysis

    Science.gov (United States)

    Drolet, Mélanie; Bénard, Élodie; Boily, Marie-Claude; Ali, Hammad; Baandrup, Louise; Bauer, Heidi; Beddows, Simon; Brisson, Jacques; Brotherton, Julia M L; Cummings, Teresa; Donovan, Basil; Fairley, Christopher K; Flagg, Elaine W; Johnson, Anne M; Kahn, Jessica A; Kavanagh, Kimberley; Kjaer, Susanne K; Kliewer, Erich V; Lemieux-Mellouki, Philippe; Markowitz, Lauri; Mboup, Aminata; Mesher, David; Niccolai, Linda; Oliphant, Jeannie; Pollock, Kevin G; Soldan, Kate; Sonnenberg, Pam; Tabrizi, Sepehr N; Tanton, Clare; Brisson, Marc

    2016-01-01

    Summary Background Human papillomavirus (HPV) vaccination programmes were first implemented in several countries worldwide in 2007. We did a systematic review and meta-analysis to assess the population-level consequences and herd effects after female HPV vaccination programmes, to verify whether or not the high efficacy reported in randomised controlled clinical trials are materialising in real-world situations. Methods We searched the Medline and Embase databases (between Jan 1, 2007 and Feb 28, 2014) and conference abstracts for time-trend studies that analysed changes, between the pre-vaccination and post-vaccination periods, in the incidence or prevalence of at least one HPV-related endpoint: HPV infection, anogenital warts, and high-grade cervical lesions. We used random-effects models to derive pooled relative risk (RR) estimates. We stratified all analyses by age and sex. We did subgroup analyses by comparing studies according to vaccine type, vaccination coverage, and years since implementation of the vaccination programme. We assessed heterogeneity across studies using I2 and χ2 statistics and we did trends analysis to examine the dose–response association between HPV vaccination coverage and each study effect measure. Findings We identified 20 eligible studies, which were all undertaken in nine high-income countries and represent more than 140 million person-years of follow-up. In countries with female vaccination coverage of at least 50%, HPV type 16 and 18 infections decreased significantly between the pre-vaccination and post-vaccination periods by 68% (RR 0·32, 95% CI 0·19–0·52) and anogenital warts decreased significantly by 61% (0·39, 0·22–0·71) in girls 13–19 years of age. Significant reductions were also recorded in HPV types 31, 33, and 45 in this age group of girls (RR 0·72, 95% CI 0·54–0·96), which suggests cross-protection. Additionally, significant reductions in anogenital warts were also reported in boys younger than 20

  5. PROJECTING POPULATION-LEVEL RESPONSE OF PURPLE SEA URCHINS TO LEAD CONTAMINATION FOR AN ESTUARINE ECOLOGICAL RISK ASSESSMENT

    Science.gov (United States)

    As part of an ecological risk assessment case study at the Portsmouth naval Shipyard (PNS), Kittery, Maine, USA, the population level effects of lead exposure to purple sea urchin, Arbacia punctulata, were investigated using a stage-classified matrix population model. The model d...

  6. A quantitative history of precipitation and hydrologic variability for the last 45 ka: Lake Titicaca, Salar de Coipasa and Salar de Uyuni, Peru and Bolivia

    Science.gov (United States)

    Nunnery, A.; Baker, P. A.; Coe, M. T.; Fritz, S. C.; Rigsby, C. A.

    2011-12-01

    Precipitation on the Bolivian/Peruvian Altiplano is dominantly controlled by the South American summer Monsoon (SASM). Over long timescales moisture transport to the Altiplano by the SASM fluctuates in intensity due to precessional insolation forcing as well as teleconnections to millennial scale abrupt temperature shifts in the North Atlantic. These long-term changes in moisture transport have been observed in multiple paleoclimate and paleo-lake level records as advances and retreats of large lakes in the terminal basin (the Salar de Uyuni). Several previous studies using energy/water balance models have been applied to paleoclimate records in attempts to provide quantitative constraints on past precipitation and temperature (P and T). For example, Blodgett et al. concluded that high paleolake stands, first dated at ca. 16,000 cal. yr BP, required P 20% higher and T 5°C colder than modern. We expand on this work conducting two experiments. The first uses a latitudinal paleohydrologic profile to reconstruct hydrological history. The second uses a terrestrial hydrology model (THMB) to "predict" lake level given changes in P and T. The profile is constructed using records from Lake Titicaca (LT), Salar de Coipasa (SC) and Salar de Uyuni (SU). LT carbonate and diatom records indicate a deep, overflowing lake for much of the last 100 ka with a distinct dry, closed-basin phase in the early to mid Holocene. A continuous sediment core from SC indicates lake level fluctuations between deep and shallow phases for the last 45 ka. A natural gamma radiation log from SU, where large paleolakes alternated with shallow salt pans characteristic of drier and/or warmer periods, shows alternation between wet and dry phases through time. These three records give evidence to the complex nature of Altiplano hydrology, most notably the ability to sustain lakes in the SC basin while exhibiting dry conditions in SU. For the second experiment, THMB, which estimates water balance and

  7. Disease, predation and demography: Assessing the impacts of bovine tuberculosis on African buffalo by monitoring at individual and population levels

    Science.gov (United States)

    Cross, P.C.; Heisey, D.M.; Bowers, J.A.; Hay, C.T.; Wolhuter, J.; Buss, P.; Hofmeyr, M.; Michel, A.L.; Bengis, Roy G.; Bird, T.L.F.; du Toit, Johan T.; Getz, W.M.

    2009-01-01

    1. Understanding the effects of disease is critical to determining appropriate management responses, but estimating those effects in wildlife species is challenging. We used bovine tuberculosis (BTB) in the African buffalo Syncerus caffer population of Kruger National Park, South Africa, as a case study to highlight the issues associated with estimating chronic disease effects in a long-lived host. 2. We used known and radiocollared buffalo, aerial census data, and a natural gradient in pathogen prevalence to investigate if: (i) at the individual level, BTB infection reduces reproduction; (ii) BTB infection increases vulnerability to predation; and (iii) at the population level, increased BTB prevalence causes reduced population growth. 3. There was only a marginal reduction in calving success associated with BTB infection, as indexed by the probability of sighting a known adult female with or without a calf (P = 0??065). 4. Since 1991, BTB prevalence increased from 27 to 45% in the southern region and from 4 to 28% in the central region of Kruger National Park. The prevalence in the northern regions was only 1??5% in 1998. Buffalo population growth rates, however, were neither statistically different among regions nor declining over time. 5. Lions Panthera leo did not appear to preferentially kill test-positive buffalo. The best (Akaike's Information Criterion corrected for small sample size) AICc model with BTB as a covariate [exp(??) = 0??49; 95% CI = (0??24-1??02)] suggested that the mortality hazard for positive individuals was no greater than for test-negative individuals. 6. Synthesis and applications. Test accuracy, time-varying disease status, and movement among populations are some of the issues that make the detection of chronic disease impacts challenging. For these reasons, the demographic impacts of bovine tuberculosis in the Kruger National Park remain undetectable despite 6 years of study on known individuals and 40 years of population counts

  8. Remote sensing and in situ mineralogic survey of the Chilean salars: An analog to Mars evaporate deposits?

    Science.gov (United States)

    Flahaut, J.; Martinot, M.; Bishop, J. L.; Davies, G. R.; Potts, N. J.

    2017-01-01

    The identification and characterization of hydrated minerals within ancient aqueous environments on Mars are high priorities for determining the past habitability of the planet. Few studies, however, have focused on characterizing the entire mineral assemblage, even though it could aide our understanding of past environments. In this study we use both spaceborne and field (VNIR spectroscopy) analyses to study the mineralogy of various salt flats (salars) of the northern region of Chile as an analog for Martian evaporites. These data are then compared to laboratory based Raman and XRD analyses for a complete overview on mineral assemblages. Central (core) and marginal zones within the salars are easily distinguished on the Landsat 8 band color composites. These areas host different mineral assemblages that often result in different landscapes. The lower elevation Salar de Atacama, located in the Andean pre-depression, is characterized by a unique thick halite crust at its center, whereas various assemblages of calcium sulfates (gypsum, bassanite, anhydrite) and sodium sulfates (mirabilite, thenardite, blodite, glauberite), borates (ulexite, pinnoite), Al/Fe- clays and carbonates (calcite, aragonite) were found at its margin. Sulfates form the main crust of the Andean salars to the east, although various compositions are observed. These compositions appear controlled by the type of feeder brine (Ca, SO4 or mixed), a result of the local geology among other factors. Sulfate crusts were found to be generally thin (<5 cm) with a sharp transition to the underlying clay, silt, or sand-rich alluvial deposits. Coupled with morphologic analyses, VNIR spectroscopy provides a powerful tool to distinguish different salt crusts. XRD analysis allowed us to quantify the mineral assemblages and assess the limitations of VNIR techniques in the presence of hydrated sulfates, which tend to mask the signatures of other minerals such as clays, chlorides, and carbonates. We found that the

  9. Active shortening and intermontane basin formation in the central Puna Plateau: Salar de Pocitos, NW Argentina (24° 37S, 67° 03W)

    Science.gov (United States)

    Strecker, M. R.; Bookhagen, B.; Alonso, R.

    2012-12-01

    With average elevations of about 3.7 km, the semi-arid to arid Puna Plateau is a first-order morphotectonic province of the southern central Andes and is an integral part of the world's second largest orogenic plateau. With few exceptions, this region consists of internally drained, partly coalesced sedimentary basins that are mainly bordered by 5- to 6-km high reverse-fault bounded basement ranges or volcanic edifices. The basins contain continental evaporites, volcanic and clastic deposits, typically between 3 and 5 km thick, and record protracted sedimentation since the Eo-Oligocene. While these basins and ranges are related to contraction, extensional tectonics associated with mafic volcanism characterizes the eastern and southern sectors of the Puna Plateau, while the eastern flanks of the plateau and the adjacent foreland are subjected to shortening. The changeover from contraction to extension in the Puna appears to have been diachronous. Along the SE plateau margin the changeover based on previously published age dating took place between 7 and 5 Ma, while areas in the central and northern Puna document shortening until 6 and 9 Ma, respectively. In the latter two areas, however, evidence for extension comparable to the eastern and southeastern plateau is scarce. This is compatible with our new observations from the Salar de Pocitos area in the western interior of the plateau, which has been characterized by protracted shortening from the Tertiary to the present-day. The N-S oriented Salar de Pocitos basin (435 km2) is the vestige of a formerly contiguous sedimentary basin that extended to the Salar de Arizaro in the west. Unlike many other basins in this region, the Pocitos basin is bordered by the limb of an anticline developed in Tertiary sedimentary rocks on the west, while the east side comprises the reverse-faulted range front of Sierra Qda. Honda. To the north the basin is closed by transverse-oriented late Miocene volcanic edifices, and to the south

  10. Population Level Effects of a Mass Media Alcohol and Breast Cancer Campaign: A Cross-Sectional Pre-Intervention and Post-Intervention Evaluation.

    Science.gov (United States)

    Martin, Neil; Buykx, Penny; Shevills, Colin; Sullivan, Claire; Clark, Lynsey; Newbury-Birch, Dorothy

    2018-01-01

    To examine the relationship between a TV-led breast cancer mass-media campaign in the North East of England (conducted in two waves: Jul/2015 and Nov/2015), awareness of the link between alcohol and cancer, intention to reduce alcohol consumption and support for alcohol related policies. Three cross-sectional surveys were conducted; one over the 2 weeks pre-campaign (n = 572); one immediately following campaign wave 1 (n = 576); and another immediately following campaign wave 2 (n = 552). Survey questions assessed; campaign exposure; awareness of the links between alcohol and related cancers; intention to change alcohol consumption; and support for alcohol related policies. The proportion of respondents indicating awareness of alcohol as a cancer risk factor was larger post-campaign compared to pre-campaign. The largest increase was seen for breast cancer with 45% aware of the links post-campaign wave 2 compared to 33% pre-campaign. The proportion of respondents indicating 'strong support' of the seven alcohol related policies significantly increased between surveys. The proportion of respondents both aware of alcohol as a cancer risk factor and supportive of the seven alcohol related policies significantly increased between surveys. There was no significant change in self-reported intention to reduce alcohol consumption amongst increasing/higher risk drinkers. These findings indicate that a mass-media campaign raising awareness of the links between alcohol and breast cancer is associated with increased awareness and alcohol related policy support at a population level. However, there was no association found with a change in short-term drinking intentions. A mass-media campaign raising awareness of the links between alcohol and breast cancer is associated with increased awareness and alcohol policy support at a population level but does not appear to be associated with a change in short term drinking intentions.

  11. Effects of passive integrated transponder tags on survival and growth of juvenile Atlantic salmon Salmo salar

    DEFF Research Database (Denmark)

    Larsen, Martin Hage; Thorn, Aske N.; Skov, Christian

    2013-01-01

    following 23 mm PIT-tag implantation had a positive impact on growth of fish smaller than 100 mm FL, we advise against the use of sutures due to high rates of fungal infection around the incision site. Hence, results suggest that surgical implantation of 23 mm PIT tags without suture closure of the incision......Background: A laboratory experiment was conducted to assess the potential impacts of surgically implanted 23 and 32 mm passive integrated transponder (PIT) tags on survival, growth, and body condition of juvenile Atlantic salmon Salmo salar. Rate of tag retention and healing of the tagging incision...... with and without suture closure of the incision, and 32 mm PIT-tag implantation without suture closure. Results: Over the 35-day experiment, mortality occurred only among fish tagged with 32 mm PIT tags (14%) and all fish larger than 103 mm FL survived. Non-sutured Atlantic salmon between 80 and 99 mm FL implanted...

  12. Multigenic Delineation of Lower Jaw Deformity in Triploid Atlantic Salmon (Salmo salar L.).

    Science.gov (United States)

    Amoroso, Gianluca; Ventura, Tomer; Cobcroft, Jennifer M; Adams, Mark B; Elizur, Abigail; Carter, Chris G

    2016-01-01

    Lower jaw deformity (LJD) is a skeletal anomaly affecting farmed triploid Atlantic salmon (Salmo salar L.) which leads to considerable economic losses for industry and has animal welfare implications. The present study employed transcriptome analysis in parallel with real-time qPCR techniques to characterise for the first time the LJD condition in triploid Atlantic salmon juveniles using two independent sample sets: experimentally-sourced salmon (60 g) and commercially produced salmon (100 g). A total of eleven genes, some detected/identified through the transcriptome analysis (fbn2, gal and gphb5) and others previously determined to be related to skeletal physiology (alp, bmp4, col1a1, col2a1, fgf23, igf1, mmp13, ocn), were tested in the two independent sample sets. Gphb5, a recently discovered hormone, was significantly (P physiology in general.

  13. Elemental composition of a migratory and a land-locked strain of Atlantic salmon Salmo salar

    Science.gov (United States)

    Rottiers, D.V.

    1993-01-01

    1. The growth and elemental composition of an anadromous strain and a land-locked strain of Atlantic salmon (Salmo salar) were compared.2. All fish were raised from the egg stage under identical conditions.3. The land-locked strain was significantly higher in lipids than the anadromous strain throughout the study.4. Results of exposure to seawater at 2-week intervals between days 431 and 512 of the study indicated that neither strain produced smolts.5. Strains could not be separated by discriminant analysis into separate groups, based on concentrations of the six most abundant elements or all ten elements sampled during the expected period of smolting (days 440–550).6. The laboratory fish differed significantly in composition from those collected in the Merrimack River.7. The loge of the whole-body element content increased significantly with loge of wet body wt in both strains.

  14. Proteolysis in salmon ( Salmo salar ) during cold storage : Effects of storage time and smoking process

    DEFF Research Database (Denmark)

    Lund, K.E.; Nielsen, Henrik Hauch

    2001-01-01

    Changes in free amino acids (FAAs), small peptides and myofibrillar proteins were investigated in salmon (Salmo salar) muscle stored at OC for up to 23 days and after the stored salmon was smoked. Storage time and smoking process did not increase the formation of FAAs and small peptides indicating...... low exopeptidase activity. During storage, SDS PAGE analysis of myofibrils showed an increase in density of bands at 16, 37, 60, 64, 67, 76 and 130 kDa, a decrease of a 32 kDa band and the appearance of four new bands of 30, 90, 95 and 113 kDa. These results indicate proteolytic degradation. A little...... change of myosin and no change of alpha -actinin and actin were observed. The smoking process itself enhances the intensity of bands, but does not change the pattern markedly except for the appearance of a 25 and 70 kDa band. Degradation pattern after smoking was not affected by storage time....

  15. Sensory and chemical changes in farmed Atlantic salmon ( Salmo salar ) during frozen storage

    DEFF Research Database (Denmark)

    Refsgaard, Hanne; Brockhoff, P.B.; Jensen, Benny

    1998-01-01

    Farmed Atlantic salmon (Salmo salar) were stored as fillets at -10 and -20 degrees C and whole at -30 degrees C. The most pronounced sensory changes were first recognized by the assessors, when the salmon samples were in the oral cavity, and were significant increases in train oil taste, metal...... during storage. The content of lipid hydroperoxides and free fatty acids also increased during storage, and the changes were fastest in salmon stored at -10 degrees C. A decrease in highly unsaturated fatty acids was observed in salmon stored at -10 and -20 degrees C. Peroxide values and the content...... of free fatty acids were shown by a partial least-squares analysis to be the best of the instrumental data in describing the sensory changes....

  16. Quality Index Method (QIM) scheme developed for farmed Atlantic salmon ( Salmo salar )

    DEFF Research Database (Denmark)

    Sveinsdóttir, K.; Hyldig, Grethe; Martinsdóttir, E.

    2003-01-01

    The aim of the study was to develop 'Quality Index Method (QIM) scheme for raw, farmed Atlantic salmon (Salmo salar) and to evaluate the scheme. in a shelf life study. QIM is based on the evaluation of key parameters in the deterioration of seafood's. Demerit points are assigned to selected...... parameters according to their importance and a Quality Index (QI) is established by cumulating the resulting scores. The maximum storage time in ice was determined with Quantitative Descriptive Analysis (QDA) of the salmon after cooking and found to be 20-21 days. This was used as a reference to enable...... prediction of the remaining storage time of raw salmon in ice with QIM. The calculated QI evolved linearly with storage time in ice (QI=0.82x (days in ice)+0.18, R-2=0.97). Individual salmon varied in QI within each storage day. However, the multivariate analysis (PLS1) demonstrated that storage time could...

  17. New immunomodulatory role of neuropeptide Y (NPY) in Salmo salar leucocytes.

    Science.gov (United States)

    González-Stegmaier, Roxana; Villarroel-Espíndola, Franz; Manríquez, René; López, Mauricio; Monrás, Mónica; Figueroa, Jaime; Enríquez, Ricardo; Romero, Alex

    2017-11-01

    Neuropeptide Y (NPY) plays different roles in mammals such as: regulate food intake, memory retention, cardiovascular functions, and anxiety. It has also been shown in the modulation of chemotaxis, T lymphocyte differentiation, and leukocyte migration. In fish, NPY expression and functions have been studied but its immunomodulatory role remains undescribed. This study confirmed the expression and synthesis of NPY in S. salar under inflammation, and validated a commercial antibody for NPY detection in teleost. Additionally, immunomodulatory effects of NPY were assayed in vitro and in vivo. Phagocytosis and superoxide anion production in leukocytes and SHK cells were induced under stimulation with a synthetic peptide. IL-8 mRNA was selectively and strongly induced in the spleen, head kidney, and isolated cells, after in vivo challenge with NPY. All together suggest that NPY is expressed in immune tissues and modulates the immune response in teleost fish. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Reduced rearing density increases postrelease migration success of Atlantic salmon (Salmo salar) smolts

    DEFF Research Database (Denmark)

    Larsen, Martin Hage; Johnsson, Jörgen I; Näslund, Joacim

    2016-01-01

    The overall aim of this study was to investigate the effect of rearing density on the post-release survival of Atlantic salmon (Salmo salar) smolts during seaward migration. Fish were either reared at conventional hatchery density or at one-third of conventional density. Three hundred one-year old...... during rearing in the hatchery. However, individuals reared at reduced density had less eroded dorsal fins and opercula relative to those from the high-density treatment. In the stream, the downstream migration success was 16% higher for fish reared at reduced density than for conspecifics kept at high......-density, but the timing of migration was similar for both groups. These novel results suggest that conventionally high rearing densities may reduce welfare and the post-release migration success of hatchery-reared Atlantic salmon...

  19. Effects of feeding and stocking density on digestion of cultured Atlantic salmon Salmo salar L.

    Science.gov (United States)

    Sun, Guoxiang; Zheng, Jimeng; Liu, Baoliang; Liu, Ying

    2014-11-01

    The combined effects of feeding rate (0.8%, 1.0%, and 1.2% initial body weight/day), feeding frequency (two, three, and four times/day) and stocking density (10, 15, and 20 kg/m3) in recirculating aquaculture systems (RAS) on growth performance, digestion and waste generation of Atlantic salmon ( Salmo salar L.) were investigated in an 8-week orthogonal experiment (L9(3)3) with a constant daily water renewal at 7.50% of total volume. No mortality occurred during the experimental period. Feed conversion ratio (FCR) varied from 0.90 to 1.13 and specific growth rate (SGR) ranged from 0.48% to 0.69%/day. SGR, thermal growth coefficient (TGC) and FCR were not significantly ( P>0.05) affected by the three factors, while net protein utilization (NPU) was significantly ( Psalmon farming industry.

  20. Towards population-level conservation in the critically endangered Antarctic blue whale: the number and distribution of their populations

    Science.gov (United States)

    Attard, Catherine R. M.; Beheregaray, Luciano B.; Möller, Luciana M.

    2016-03-01

    Population-level conservation is required to prevent biodiversity loss within a species, but it first necessitates determining the number and distribution of populations. Many whale populations are still depleted due to 20th century whaling. Whales are one of the most logistically difficult and expensive animals to study because of their mobility, pelagic lifestyle and often remote habitat. We tackle the question of population structure in the Antarctic blue whale (Balaenoptera musculus intermedia) - a critically endangered subspecies and the largest extant animal - by capitalizing on the largest genetic dataset to date for Antarctic blue whales. We found evidence of three populations that are sympatric in the Antarctic feeding grounds and likely occupy separate breeding grounds. Our study adds to knowledge of population structure in the Antarctic blue whale. Future research should invest in locating the breeding grounds and migratory routes of Antarctic blue whales through satellite telemetry to confirm their population structure and allow population-level conservation.

  1. Does Digital Video Advertising Increase Population-Level Reach of Multimedia Campaigns? Evidence From the 2013 Tips From Former Smokers Campaign.

    Science.gov (United States)

    Davis, Kevin C; Shafer, Paul R; Rodes, Robert; Kim, Annice; Hansen, Heather; Patel, Deesha; Coln, Caryn; Beistle, Diane

    2016-09-14

    Federal and state public health agencies in the United States are increasingly using digital advertising and social media to promote messages from broader multimedia campaigns. However, little evidence exists on population-level campaign awareness and relative cost efficiencies of digital advertising in the context of a comprehensive public health education campaign. Our objective was to compare the impact of increased doses of digital video and television advertising from the 2013 Tips From Former Smokers (Tips) campaign on overall campaign awareness at the population level. We also compared the relative cost efficiencies across these media platforms. We used data from a large national online survey of approximately 15,000 US smokers conducted in 2013 immediately after the conclusion of the 2013 Tips campaign. These data were used to compare the effects of variation in media dose of digital video and television advertising on population-level awareness of the Tips campaign. We implemented higher doses of digital video among selected media markets and randomly selected other markets to receive similar higher doses of television ads. Multivariate logistic regressions estimated the odds of overall campaign awareness via digital or television format as a function of higher-dose media in each market area. All statistical tests used the .05 threshold for statistical significance and the .10 level for marginal nonsignificance. We used adjusted advertising costs for the additional doses of digital and television advertising to compare the cost efficiencies of digital and television advertising on the basis of costs per percentage point of population awareness generated. Higher-dose digital video advertising was associated with 94% increased odds of awareness of any ad online relative to standard-dose markets (Pdigital advertising was associated with a marginally nonsignificant increase (46%) in overall campaign awareness regardless of media format (P=.09). Higher

  2. Population-level scaling of avian migration speed with body size and migration distance for powered fliers.

    Science.gov (United States)

    La Sorte, Frank A; Fink, Daniel; Hochachka, Wesley M; DeLong, John P; Kelling, Steve

    2013-08-01

    Optimal migration theory suggests specific scaling relationships between body size and migration speed for individual birds based on the minimization of time, energy, and risk. Here we test if the quantitative predictions originating from this theory can be detected when migration decisions are integrated across individuals. We estimated population-level migration trajectories and daily migration speeds for the combined period 2007-2011 using the eBird data set. We considered 102 North American bird species that use flapping or powered flight during migration. Many species, especially in eastern North America, had looped migration trajectories that traced a clockwise path with an eastward shift during autumn migration. Population-level migration speeds decelerated rapidly going into the breeding season, and accelerated more slowly during the transition to autumn migration. In accordance with time minimization predictions, spring migration speeds were faster than autumn migration speeds. In agreement with optimality predictions, migration speeds of powered flyers scaled negatively with body mass similarly during spring and autumn migration. Powered fliers with longer migration journeys also had faster migration speeds, a relationship that was more pronounced during spring migration. Our findings indicate that powered fliers employed a migration strategy that, when examined at the population level, was in compliance with optimality predictions. These results suggest that the integration of migration decisions across individuals does result in population-level patterns that agree with theoretical expectations developed at the individual level, indicating a role for optimal migration theory in describing the mechanisms underlying broadscale patterns of avian migration for species that use powered flight.

  3. Salares versus coastal ecotypes of quinoa: Salinity responses in Chilean landraces from contrasting habitats.

    Science.gov (United States)

    Ruiz, Karina B; Aloisi, Iris; Del Duca, Stefano; Canelo, Valentina; Torrigiani, Patrizia; Silva, Herman; Biondi, Stefania

    2016-04-01

    Quinoa (Chenopodium quinoa Willd.) is a highly salt-tolerant species subdivided into five ecotypes and exhibiting broad intra-specific differences in tolerance levels. In a greenhouse study, Chilean landraces belonging either to the salares (R49) or coastal lowlands (VI-1, Villarrica) ecotype with contrasting agro-ecological origins were investigated for their responses to high salinity. The effects of two levels of salinity, 100 (T1) and 300 (T2) mM NaCl, on plant growth and on some physiological parameters were measured. Leaf and root Na(+) accumulation differed among landraces. T2 reduced growth and seed yield in all landraces with maximum inhibition relative to controls in R49. Salinity negatively affected chlorophyll and total polyphenol content (TPC) in VI-1 and Villarrica but not R49. Germination on saline or control media of seeds harvested from plants treated or not with NaCl was sometimes different; the best performing landrace was R49 insofar as 45-65% of seeds germinated on 500 mM NaCl-containing medium. In all landraces, average seedling root length declined strongly with increasing NaCl concentration, but roots of R49 were significantly longer than those of VI-1 and Villarrica up to 300 mM NaCl. Salt caused increases in seed TPC relative to controls, but radical scavenging capacity was higher only in seeds from T2 plants of R49. Total SDS-extractable seed proteins were resolved into distinct bands (10-70 kDa) with some evident differences between landraces. Salt-induced changes in protein patterns were landrace-specific. The responses to salinity of the salares landrace are discussed in relation to its better adaptation to an extreme environment. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  4. Características geoquímicas generales del sistema salino del Salar de Llamara (Chile

    Directory of Open Access Journals (Sweden)

    Gimeno, M. J.

    1996-04-01

    Full Text Available «Norte Grande de Chile» is a wide area characterized by arid climatic features. This region contains numerous undrained basins in which development of saline systems called salars takes place. The scattered ponds in «salar de Llamará» system contain nearneutral brines of the Na-Cl type. Moreover, mineralogic composition of this salar deposits is mainly gypsiferous.This saline system has been sampled throughout two summer seasons. Compositional evolution of solutions (through application of chemical divide rule from Hardie and Eugster, 1970 shows that its trend has been influenced by the precipitation of calcite and gypsum. Saturation states calculated by PHRQPITZ geochemical code have pointed out that all brines sampled were saturated with regard to both minerals.Theoretical evolution of brines in advanced evaporative stages has been carried out by means of Valyashko diagram. Saline mineral s which appear together with gypsum in salar deposits confirm the forecasts of this method. After gypsum, progressive evaporation causes the precipitation of halite. Crystallization of more soluble sulphates, borates and nitrates would occur in more advanced stages near to brine dryness.El salar de Llamará es un sistema salino que se mantiene activo gracias a su especial situación geomorfológica y a las características climáticas de la zona donde se localiza, conocida como «Norte Grande de Chile». Las acumulaciones superficiales de agua constituyen verdaderas salmueras de tipo clorurado-sódico y pH aproximadamente neutro. Por otra parte, la composición de los depósitos bajo lámina de agua del salar es fundamentalmente yesífera.El desmuestre realizado sobre el sistema a lo largo de dos campañas estivales, y la interpretación de la evolución temporal de sus características composicionales a través de la regla de la divisoria química, han puesto de manifiesto que la composición de las salmueras se ha encontrado determinada por

  5. State diagram of salmon (Salmo salar) gelatin films.

    Science.gov (United States)

    Díaz, Paulo; López, Daniel; Matiacevich, Silvia; Osorio, Fernando; Enrione, Javier

    2011-11-01

    A state diagram presents different physical states of a biomaterial as a function of solid content and temperature. Despite their technological interest, little information is available on protein systems such as gelatin/water mixtures. The objective of this work was to develop state diagrams of salmon gelatin (SG) and bovine gelatin (BG) in order to determine maximal freeze concentration parameters (T'(g) , T'(m) and X(s') ) and to relate possible differences to their biochemical characteristics. Biochemical characterisation of SG showed lower molecular weight and iminoacid concentration compared with BG. Likewise, the glass transition temperature (T(g) ) was lower for SG at X(s) > 0.8, which was associated with its lower molecular weight. Unexpectedly, the depression of freezing temperature (T(f) ) was greater for SG at X(s) > 0.1, which was associated with its higher ash content. Isothermal annealing produced effective values of T'(g) ≈ - 52 °C, T'(m) ≈ - 46 °C and X'(s) ≈ 0.6 for both gelatins. Interestingly, the enthalpy change associated with T'(m) (ΔH T m) was significantly higher for SG than for BG after annealing, indicating a higher proportion of ice present at about - 50 °C. Maximal freeze concentration parameters were similar between the two gelatins, though differences in biochemical properties were evident. The results show that there are likely different ways of interaction of SG and BG with water. Copyright © 2011 Society of Chemical Industry.

  6. Diet, feeding patterns, and prey selection of subyearling Atlantic salmon (Salmo salar) and subyearling chinook salmon (Oncorhynchus tshawytscha) in a tributary of Lake Ontario

    Science.gov (United States)

    Johnson, J. H.; Nash, K. J.; Chiavelli, R. A.; DiRado, J. A.; Mackey, G. E.; Knight, J. R.; Diaz, A. R.

    2017-01-01

    Since juvenile Atlantic salmon (Salmo salar) and Chinook salmon (Oncorhynchus tshawytscha) occupy a similar habitat in Lake Ontario tributaries, we sought to determine the degree of diet similarity between these species in order to assess the potential for interspecific competition. Atlantic salmon, an historically important but currently extirpated component of the Lake Ontario fish community, are the focus of a bi-national restoration effort. Presently this effort includes the release of hatchery produced juvenile Atlantic salmon in Lake Ontario tributaries. These same tributaries support substantial numbers of naturally reproduced juvenile Pacific salmonids including Chinook salmon. Subyearling Atlantic salmon and subyearling Chinook salmon had significantly different diets during each of the three time periods examined. Atlantic salmon fed slightly more from the benthos than from the drift and consumed mainly chirononmids (47.0%) and ephemeropterans (21.1%). The diet of subyearling Chinook salmon was more closely associated with the drift and consisted mainly of chironomids (60.2%) and terrestrial invertebrates (16.0%). Low diet similarity between subyearling Atlantic salmon and subyearling Chinook salmon likely minimizes competitive interactions for food between these species in Lake Ontario tributaries. However, the availability of small prey such as chironomids which comprise over 50% of the diet of each species, soon after emergence, could constitute a short term resource limitation. To our knowledge this is the first study of interspecific diet associations between these two important salmonid species.

  7. Population-Level Outcomes with a 2-Step Approach for Gestational Diabetes Screening and Diagnosis.

    Science.gov (United States)

    Donovan, L E; Edwards, A L; Savu, A; Butalia, S; Ryan, E A; Johnson, J A; Kaul, P

    2017-12-01

    To examine outcomes associated with alternative glucose thresholds in a 2-step approach for screening and diagnosing gestational diabetes mellitus (GDM). We studied 178,527 pregnancies between 2008 and 2012 in Alberta, Canada. They were categorized retrospectively as normal 50 g screen (n=144,191); normal 75 g oral glucose tolerance test (OGTT) (n=21,248); abnormal at glucose thresholds suggested by the International Association of Diabetes and Pregnancy Group (IADPSG) (HAPO 1.75, n=4308); abnormal at glucose thresholds associated with an odds ratio of 2.0 for adverse events in the Hyperglycemia and Adverse Pregnancy Outcomes (HAPO) study. This latter group, which would have been treated for GDM based on customary care, was further divided into those with 1 (HAPO 2-1 n=5528) or 2 or more abnormal glucose values (HAPO 2-2 n=3252). Main outcomes were large for gestational age (LGA), induced labour and Cesarean-section rates. LGA rates were 8.2%, 10.5%, 14.2%, 11.8% and 16.5% among normal 50 g, normal 75 g OGTT, HAPO 1.75, HAPO 2-1, and HAPO 2-2 groups, respectively. Labour induction and caesarean-section rates were 29.6% and 36.2% in the IADPSG, 38.2% and 36.8% in the HAPO 2-1 group, and 42.3% and 41.1% in the HAPO 2-2 groups, respectively. Excessive maternal weight (≥91 kg) was associated with a higher risk for all adverse outcomes. The 2-step approach effectively identifies pregnancies at low risk for adverse outcomes. Labelling influences induction practice. Any glucose intolerance increases risk for adverse outcomes, and pregnancies with highest (2 or higher) abnormal glucose values remain at greatest risk. Further research is needed to determine whether glycemic thresholds for GDM diagnosis should incorporate information about maternal weight. Copyright © 2017 Diabetes Canada. Published by Elsevier Inc. All rights reserved.

  8. Population-level administration of AlcoholEdu for college: an ARIMA time-series analysis.

    Science.gov (United States)

    Wyatt, Todd M; Dejong, William; Dixon, Elizabeth

    2013-08-01

    Autoregressive integrated moving averages (ARIMA) is a powerful analytic tool for conducting interrupted time-series analysis, yet it is rarely used in studies of public health campaigns or programs. This study demonstrated the use of ARIMA to assess AlcoholEdu for College, an online alcohol education course for first-year students, and other health and safety programs introduced at a moderate-size public university in the South. From 1992 to 2009, the university administered annual Core Alcohol and Drug Surveys to samples of undergraduates (Ns = 498 to 1032). AlcoholEdu and other health and safety programs that began during the study period were assessed through a series of quasi-experimental ARIMA analyses. Implementation of AlcoholEdu in 2004 was significantly associated with substantial decreases in alcohol consumption and alcohol- or drug-related negative consequences. These improvements were sustained over time as succeeding first-year classes took the course. Previous studies have shown that AlcoholEdu has an initial positive effect on students' alcohol use and associated negative consequences. This investigation suggests that these positive changes may be sustainable over time through yearly implementation of the course with first-year students. ARIMA time-series analysis holds great promise for investigating the effect of program and policy interventions to address alcohol- and drug-related problems on campus.

  9. The Relationship Between Structural Game Characteristics and Gambling Behavior: A Population-Level Study.

    Science.gov (United States)

    Leino, Tony; Torsheim, Torbjørn; Blaszczynski, Alex; Griffiths, Mark; Mentzoni, Rune; Pallesen, Ståle; Molde, Helge

    2015-12-01

    The aim of this study was to examine the relationship between the structural characteristics and gambling behavior among video lottery terminal (VLT) gamblers. The study was ecological valid, because the data consisted of actual gambling behavior registered in the participants natural gambling environment without intrusion by researchers. Online behavioral tracking data from Multix, an eight game video lottery terminal, were supplied by Norsk-Tipping (the state owned gambling company in Norway). The sample comprised the entire population of Multix gamblers (N = 31,109) who had gambled in January 2010. The individual number of bets made across games was defined as the dependent variable, reward characteristics of a game (i.e., payback percentage, hit frequency, size of winnings and size of jackpot) and bet characteristics of a game (i.e., range of betting options and availability of advanced betting options) served as the independent variables. Control variables were age and gender. Two separate cross-classified multilevel random intercepts models were used to analyze the relationship between bets made, reward characteristics and bet characteristics, where the number of bets was nested within both individuals and within games. The results show that the number of bets is positively associated with payback percentage, hit frequency, being female and age, and negatively associated with size of wins and range of available betting options. In summary, the results show that the reward characteristics and betting options explained 27% and 15% of the variance in the number of bets made, respectively. It is concluded that structural game characteristics affect gambling behavior. Implications of responsible gambling are discussed.

  10. Modeling the Population-Level Processes of Biodiversity Gain and Loss at Geological Timescales.

    Science.gov (United States)

    Fortelius, Mikael; Geritz, Stefan; Gyllenberg, Mats; Raia, Pasquale; Toivonen, Jaakko

    2015-12-01

    The path of species diversification is commonly observed by inspecting the fossil record. Yet, how species diversity changes at geological timescales relate to lower-level processes remains poorly understood. Here we use mathematical models of spatially structured populations to show that natural selection and gradual environmental change give rise to discontinuous phenotype changes that can be connected to speciation and extinction at the macroevolutionary level. In our model, new phenotypes arise in the middle of the environmental gradient, while newly appearing environments are filled by existing phenotypes shifting their adaptive optima. Slow environmental change leads to loss of phenotypes in the middle of the extant environmental range, whereas fast change causes extinction at one extreme of the environmental range. We compared our model predictions against a well-known yet partially unexplained pattern of intense hoofed mammal diversification associated with grassland expansion during the Late Miocene. We additionally used the model outcomes to cast new insight into Cope's law of the unspecialized. Our general finding is that the rate of environmental change determines where generation and loss of diversity occur in the phenotypic and physical spaces.

  11. [Traumatic experiences in elderly Germans. Importance for mental and physical health at a population level].

    Science.gov (United States)

    Glaesmer, H

    2014-04-01

    World War II (WWII) is probably the most distressing and fatal historical event in Europe's recent past. Research on mental and physical health sequelae of these traumatic experiences from WWII has only started recently. An overview on the findings from several population-based studies investigating the mental and physical health outcomes of traumatic experiences in the German elderly (born prior to 1946), especially from WWII, is given. The results presented here are based on several population-based representative studies regarding several aspects of mental and physical health in the elderly. About 40-50 % of the elderly German population report at least one traumatic event, mostly from WWII. Traumatic experiences are related to higher rates of depressive and somatoform disorders, posttraumatic stress disorder, and physical morbidity, which are associated with increased health care utilization. The findings underline that the negative effects on health are long-term, manifold, and serious. Some of the elderly need psychotherapeutic interventions. Thus, a specific internet-based psychotherapeutic approach (ITT) is briefly presented. However, the majority of the elderly generally use other kinds of medical care, such as primary care, inpatient care, and geriatric care. It seems useful and necessary to pay more attention to the historical and biographical backgrounds of the patients to see and understand the current symptoms from this aspect.

  12. Orthostatic hypotension does not increase cardiovascular risk in the elderly at a population level.

    Science.gov (United States)

    Casiglia, Edoardo; Tikhonoff, Valérie; Caffi, Sandro; Boschetti, Giovanni; Giordano, Nunzia; Guidotti, Federica; Segato, Federico; Mazza, Alberto; Grasselli, Carla; Saugo, Mario; Rigoni, Giulio; Guglielmi, Francesco; Martini, Bortolo; Palatini, Paolo

    2014-01-01

    The general belief that orthostatic hypotension (OH) predisposes to cardiovascular events is based on sparse and contradictory data, rarely derived from population studies. A total of 1,016 men and women aged ≥65 years was studied in a 12-year epidemiological population-based study. Cardiovascular events were detected in subjects with and without OH (blood pressure (BP) decrease ≥20mm Hg for systolic or ≥10mm Hg for diastolic), and Cox analysis was performed including OH as an independent variable. In univariate analysis, coronary (20.2% vs. 13.1%, P = 0.05), cerebrovascular (13.1% vs. 8.4%, P = 0.05), and heart failure (HF) events (20.2% vs. 13.8%, P = 0.03) were apparently more incidental in subjects with OH than in those without OH. Nevertheless, after adjusting for age, gender, and systolic BP as confounders, OH did not act as a cardiovascular predictor (relative risk for cerebrovascular events 1.33, 95% confidence interval (CI), 0.78-2.2, for coronary events 1.25, CI 0.82-1.88, for HF 1.07, CI 0.71-1.62, for arrhythmias 0.82, CI 0.40-1.37, and for syncope 0.58, CI 0.13-2.71). Although OH seems to be a predictor of coronary, cerebrovascular, and HF events, no predictive role was found in models that include biological confounders. Independent of the cause of OH, age and systolic BP, which are positively associated with OH, fully explain the greater incidence of cardiovascular events and the greater cardiovascular risk observed in subjects with OH.

  13. Population-Level Impact of Ontario's Infant Rotavirus Immunization Program: Evidence of Direct and Indirect Effects.

    Directory of Open Access Journals (Sweden)

    Sarah E Wilson

    Full Text Available To evaluate the direct and indirect population impact of rotavirus (RV immunization on hospitalizations and emergency department (ED visits for acute gastroenteritis (AGE in Ontario before and after the publicly-funded RV immunization program.Administrative data was used to identify ED visits and hospitalizations for all Ontarians using ICD-10 codes. We used two outcome definitions: RV-specific AGE (RV-AGE and codes representing RV-, other viral and cause unspecified AGE ("overall AGE". The pre-program and public program periods were August 1, 2005 to July 31, 2011; and August 1, 2011 to March 31, 2013, respectively. A negative binominal regression model that included the effect of time was used to calculate rates and rate ratios (RRs and 95% confidence intervals (CIs for RV-AGE and overall AGE between periods, after adjusting for age, seasonality and secular trends. Analyses were conducted for all ages combined and age stratified.Relative to the pre-program period, the adjusted RRs for RV-AGE and overall AGE hospitalizations in the public program period were 0.29 (95%CI: 0.22-0.39 and 0.68 (95%CI: 0.62-0.75, respectively. Significant reductions in RV-AGE hospitalizations were noted overall and for the following age bands: = 65 years (RR 0.80, 95%CI: 0.72-0.90. The program was associated with adjusted RRs of 0.32 (95% CI: 0.20-0.52 for RV-AGE ED visits and 0.90 (95% CI: 0.85-0.96 for overall AGE ED visits.This large, population-based study provides evidence of the impact of RV vaccine in preventing hospitalizations and ED visits for RV-AGE and overall AGE, including herd effects.

  14. Awareness and perceived fairness of Option B+ in Malawi: A population-level perspective

    Science.gov (United States)

    Yeatman, Sara; Trinitapoli, Jenny

    2017-03-08

    Policies for rationing antiretroviral therapy (ART) have been subject to on-going ethical debates. Introduced in Malawi in 2011, Option B+ prioritized HIV-positive pregnant women for lifelong ART regardless of the underlying state of their immune system, shifting the logic of allocation away from medical eligibility. Despite the rapid expansion of this policy, we know little about how it has been understood and interpreted by the people it affects. We assessed awareness and perceived fairness of the prioritization system for ART among a population-based sample of young women (n = 1440) and their partners (n = 574) in southern Malawi. We use a card-sort technique to elicit understandings of who gets ART under Option B+ and who should be prioritized, and we compare perceptions to actual ART policy using sequence analysis and optimal matching. We then use ordered logistic regression to identify the factors associated with policy awareness. In 2015, only 30.7% of women and 21.1% of male partners understood how ART was being distributed. There was widespread confusion around whether otherwise healthy HIV-positive pregnant women could access ART under Option B + . Nonetheless, more young adults thought that the fairest policy should prioritize such women than believed the actual policy did. Women who were older, more educated or had recently engaged with the health system through antenatal care or ART had more accurate understandings of Option B + . Among men, policy awareness was lower, and was patterned only by education. Although most respondents were unaware that Option B+ afforded ART access to healthy-pregnant women, Malawians support the prioritization of pregnant women. Countries adopting Option B+ or other new ART policies such as universal test-and-treat should communicate the policies and their rationales to the public - such transparency would be more consistent with a fair and ethical process and could additionally serve to clarify confusion and

  15. Changes in Fertility at the Population Level in the Era of ART in Rural Malawi.

    Science.gov (United States)

    McLean, Estelle; Price, Alison; Chihana, Menard; Kayuni, Ndoliwe; Marston, Milly; Koole, Olivier; Zaba, Basia; Crampin, Amelia

    2017-08-01

    HIV reduces fertility through biological and social pathways, and antiretroviral treatment (ART) can ameliorate these effects. In northern Malawi, ART has been available since 2007 and lifelong ART is offered to all pregnant or breastfeeding HIV-positive women. Using data from the Karonga Health and Demographic Surveillance Site in Malawi from 2005 to 2014, we used total and age-specific fertility rates and Cox regression to assess associations between HIV and ART use and fertility. We also assessed temporal trends in in utero and breastfeeding HIV and ART exposure among live births. From 2005 to 2014, there were 13,583 live births during approximately 78,000 person years of follow-up of women aged 15-49 years. The total fertility rate in HIV-negative women decreased from 6.1 [95% confidence interval (CI): 5.5 to 6.8] in 2005-2006 to 5.1 (4.8-5.5) in 2011-2014. In HIV-positive women, the total fertility rate was more stable, although lower, at 4.4 (3.2-6.1) in 2011-2014. In 2011-2014, compared with HIV-negative women, the adjusted (age, marital status, and education) hazard ratio was 0.7 (95% CI: 0.6 to 0.9) and 0.8 (95% CI: 0.6 to 1.0) for women on ART for at least 9 months and not (yet) on ART, respectively. The crude fertility rate increased with duration on ART up to 3 years before declining. The proportion of HIV-exposed infants decreased, but the proportion of ART-exposed infants increased from 2.4% in 2007-2010 to 3.5% in 2011-2014. Fertility rates in HIV-positive women are stable in the context of generally decreasing fertility. Despite a decrease in HIV-exposed infants, there has been an increase in ART-exposed infants.

  16. Effectiveness of emamectin benzoate for treatment of Lepeophtheirus salmonis on farmed Atlantic salmon Salmo salar in the Bay of Fundy, Canada.

    Science.gov (United States)

    Jones, Patti G; Hammell, K Larry; Dohoo, Ian R; Revie, Crawford W

    2012-12-03

    Emamectin benzoate (an avermectin chemotherapeutant administered to fish as an in-feed treatment) has been used to treat infestations of sea lice Lepeophtheirus salmonis on farmed Atlantic salmon Salmo salar in the Bay of Fundy, New Brunswick, Canada, since 1999. This retrospective study examined the effectiveness of 114 emamectin benzoate treatment episodes from 2004 to 2008 across 54 farms. Study objectives were to establish whether changes in the effectiveness of emamectin benzoate were present for this period, examine factors associated with treatment outcome, and determine variables that influenced differences in L. salmonis abundance after treatment. The analysis was carried out in 2 parts: first, trends in treatment effectiveness and L. salmonis abundance were explored, and second, statistical modelling (linear and logistic regression) was used to examine the effects of multiple variables on post-treatment abundance and treatment outcome. Post-treatment sea lice abundance increased in the later years examined. Mean abundance differed between locations in the Bay of Fundy, and higher numbers were found at farms closer to the mainland and lower levels were found in the areas around Grand Manan Island. Treatment effectiveness varied by geographical region and decreased over time. There was an increased risk for unsuccessful treatments in 2008, and treatments applied during autumn months were more likely to be ineffective than those applied during summer months.

  17. Piloting a Non-Invasive Genetic Sampling Method for Evaluating Population-Level Benefits of Wildlife Crossing Structures

    Directory of Open Access Journals (Sweden)

    Anthony P. Clevenger

    2010-03-01

    Full Text Available Intuitively, wildlife crossing structures should enhance the viability of wildlife populations. Previous research has demonstrated that a broad range of species will use crossing structures, however, questions remain as to whether these measures actually provide benefits to populations. To assess this, studies will need to determine the number of individuals using crossings, their sex, and their genetic relationships. Obtaining empirical data demonstrating population-level benefits for some species can be problematic and challenging at best. Molecular techniques now make it possible to identify species, individuals, their sex, and their genetic relatedness from hair samples collected through non-invasive genetic sampling (NGS. We describe efforts to pilot a method to assess potential population-level benefits of wildlife crossing structures. We tested the feasibility of a prototype NGS system designed to sample hair from black bears (Ursus americanus and grizzly bears (U. arctos at two wildlife underpasses. The piloted hair-sampling method did not deter animal use of the trial underpasses and was effective at sampling hair from more than 90% of the bear crossing events at the underpasses. Hair samples were also obtained from non-target carnivore species, including three out of five (60% cougar (Puma concolor crossing events. Individual identification analysis revealed that three female and two male grizzly bears used one wildlife underpass, whereas two female and three male black bears were identified as using the other underpass. Of the 36 hair samples from bears analyzed, five failed, resulting in an 87% extraction success rate, and six more were only identified to species. Overall, 70% of the hair samples from bears collected in the field had sufficient DNA for extraction purposes. Preliminary data from our NGS suggest the technique can be a reliable method to assess the population-level benefits of Banff wildlife crossings. Furthermore, NGS

  18. Overall multi-media persistence as an indicator of potential for population-level intake of environmental contaminants

    Energy Technology Data Exchange (ETDEWEB)

    MacLeod, Matthew; McKone, Thomas E.

    2003-06-01

    Although it is intuitively apparent that population-level exposure to contaminants dispersed in the environment must related to the persistence of the contaminant, there has been little effort to formally quantify this link. In this paper we investigate the relationship between overall persistence in a multimedia environment and the population-level exposure as expressed by intake fraction (iF), which is the cumulative fraction of chemical emitted to the environment that is taken up by members of the population. We first confirm that for any given chemical contaminant and emission scenario the definition of iF implies that it is directly proportional to the overall multi-media persistence, P{sub OV}. We show that the proportionality constant has dimensions of time and represents the characteristic time for population intake (CTI) of the chemical from the environment. We then apply the CalTOX fate and exposure model to explore how P{sub OV} and CTI combine to determine the magnitude of iF. We find that CTI has a narrow range of possible values relative to P{sub OV} across multiple chemicals and emissions scenarios. We use data from the Canadian Environmental Protection Act Priority Substance List (PSL1) Assessments to show that exposure assessments based on empirical observation are consistent with interpretations from the model. The characteristic time for intake along different dominant exposure pathways is discussed. Results indicate that P{sub OV} derived from screening-level assessments of persistence, bioaccumulation potential, and toxicity (PBT) is a useful indicator of the potential for population-level exposure.

  19. What Is the Most Bothersome Lower Urinary Tract Symptom? Individual- and Population-level Perspectives for Both Men and Women

    Science.gov (United States)

    Agarwal, Arnav; Eryuzlu, Leyla N.; Cartwright, Rufus; Thorlund, Kristian; Tammela, Teuvo L.J.; Guyatt, Gordon H.; Auvinen, Anssi; Tikkinen, Kari A.O.

    2014-01-01

    Background No study has compared the bothersomeness of all lower urinary tract symptoms (LUTS) using a population-based sample of adults. Despite this lack of evidence, investigators have often cited their LUTS of interest as the “most bothersome” or “one of the most bothersome.” Objective To compare the population- and individual-level burden of LUTS in men and women. Design, setting, and participants In this population-based cross-sectional study, questionnaires were mailed to 6000 individuals (18–79 yr of age) randomly identified from the Finnish Population Register. Outcome measurements and statistical analysis The validated Danish Prostatic Symptom Score questionnaire was used for assessment of bother of 12 different LUTS. The age-standardized prevalence of at least moderate bother was calculated for each symptom (population-level burden). Among symptomatic individuals, the proportion of affected individuals with at least moderate bother was calculated for each symptom (individual-level bother). Results and limitations A total of 3727 individuals (62.4%) participated (53.7% female). The LUTS with the greatest population-level burden were urgency (7.9% with at least moderate bother), stress urinary incontinence (SUI) (6.5%), nocturia (6.0%), postmicturition dribble (5.8%), and urgency urinary incontinence (UUI) (5.0%). Burden from incontinence symptoms was higher in women than men, and the opposite was true for voiding and postmicturition symptoms. At the individual level, UUI was the most bothersome for both genders. Although the response proportion was high, approximately a third did not participate. Conclusions Both men and women with UUI report moderate or major bother more frequently than individuals with other LUTS. At the population level, the most prevalent bothersome symptoms are urgency, SUI, and nocturia. Patient summary Urinary urgency was the most common troubling symptom in a large population-based study; however, for individuals

  20. Mobile Phone Surveys for Collecting Population-Level Estimates in Low- and Middle-Income Countries: A Literature Review.

    Science.gov (United States)

    Gibson, Dustin G; Pereira, Amanda; Farrenkopf, Brooke A; Labrique, Alain B; Pariyo, George W; Hyder, Adnan A

    2017-05-05

    National and subnational level surveys are important for monitoring disease burden, prioritizing resource allocation, and evaluating public health policies. As mobile phone access and ownership become more common globally, mobile phone surveys (MPSs) offer an opportunity to supplement traditional public health household surveys. The objective of this study was to systematically review the current landscape of MPSs to collect population-level estimates in low- and middle-income countries (LMICs). Primary and gray literature from 7 online databases were systematically searched for studies that deployed MPSs to collect population-level estimates. Titles and abstracts were screened on primary inclusion and exclusion criteria by two research assistants. Articles that met primary screening requirements were read in full and screened for secondary eligibility criteria. Articles included in review were grouped into the following three categories by their survey modality: (1) interactive voice response (IVR), (2) short message service (SMS), and (3) human operator or computer-assisted telephone interviews (CATI). Data were abstracted by two research assistants. The conduct and reporting of the review conformed to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. A total of 6625 articles were identified through the literature review. Overall, 11 articles were identified that contained 19 MPS (CATI, IVR, or SMS) surveys to collect population-level estimates across a range of topics. MPSs were used in Latin America (n=8), the Middle East (n=1), South Asia (n=2), and sub-Saharan Africa (n=8). Nine articles presented results for 10 CATI surveys (10/19, 53%). Two articles discussed the findings of 6 IVR surveys (6/19, 32%). Three SMS surveys were identified from 2 articles (3/19, 16%). Approximately 63% (12/19) of MPS were delivered to mobile phone numbers collected from previously administered household surveys. The majority of MPS (11

  1. Spectral reflectance variations in stay-green and conventional maize hybrids as response to population level stress

    Science.gov (United States)

    Weber, C.; Acciaresi, H. A.; Rodríguez, E. J.; Antonietta, M.; Guiamet, J. J.; Tocho, J. O.

    2011-05-01

    Stress caused by increase population density in maize produce significant yield loss. To remedy it, photosynthetic activity maintenance even under unfavorable conditions is required. Senescence delay induced by stress in stay-green genotypes (SG) could contribute to maintaining photosynthetic capacity. In this work we observed differences in reflectance curves of two hybrids (SG and no SG) when population level increased. Significant differences in chlorophyll absorption spectral region were observed. Therefore spectral signatures studies maize could help to understanding of the physiological basis of SG character to predict the growing conditions in which these hybrids would express their production potential.

  2. A population level atlas of Mus musculus craniofacial skeleton and automated image-based shape analysis.

    Science.gov (United States)

    Maga, A Murat; Tustison, Nicholas J; Avants, Brian B

    2017-09-01

    few cervical vertebrae. We have been using this template in our lab to segment and isolate cranial structures in an automated fashion from a mixed population of mice, including craniofacial mutants, aged 4-12.5 weeks. As a secondary contribution, we demonstrate an application of nearly automated shape analysis, using symmetric diffeomorphic image registration. This approach, which we call diGPA, closely approximates the popular generalized Procrustes analysis (GPA) but negates the collection of anatomical landmarks. We achieve our goals by using the open-source advanced normalization tools (ANT) image quantification library, as well as its associated R library (ANTsR) for statistical image analysis. Finally, we make a plea to investigators to commit to using open imaging standards and software in their labs to the extent possible to increase the potential for data exchange and improve the reproducibility of findings. Future work will incorporate more anatomical detail (such as individual cranial bones, turbinals, dentition, middle ear ossicles) and more diversity into the template. © 2017 Anatomical Society.

  3. Variation in population levels of sedentary time in European adults according to cross-European studies: a systematic literature review within DEDIPAC

    NARCIS (Netherlands)

    Loyen, A.; Verloigne, M.; Hecke, L. van; Hendriksen, I.; Lakerveld, J.; Steene-Johannessen, J.; Koster, A.; Donnelly, A.; Ekelund, U.; Deforche, B.; Bourdeaudhuij, I. de; Brug, J.; Ploeg, H.P. van der

    2016-01-01

    Background: Sedentary behaviour is increasingly recognized as a public health risk that needs to be monitored at the population level. Across Europe, there is increasing interest in assessing population levels of sedentary time. This systematic literature review aims to provide an overview of all

  4. Variation in population levels of sedentary time in European adults according to cross-European studies: a systematic literature review within DEDIPAC

    NARCIS (Netherlands)

    Loyen, A; Verloigne, M.; Van Hecke, L.; Hendriksen, I.; Lakerveld, J.; Steene-Johannessen, J.; Koster, A.; Donnelly, A.; Ekelund, U.; Deforche, B.; De Bourdeaudhuij, I.; Brug, J.; van der Ploeg, H.P.

    2016-01-01

    Background Sedentary behaviour is increasingly recognized as a public health risk that needs to be monitored at the population level. Across Europe, there is increasing interest in assessing population levels of sedentary time. This systematic literature review aims to provide an overview of all

  5. The Population Level Cascade of Care for Hepatitis C in British Columbia, Canada: The BC Hepatitis Testers Cohort (BC-HTC).

    Science.gov (United States)

    Janjua, Naveed Z; Kuo, Margot; Yu, Amanda; Alvarez, Maria; Wong, Stanley; Cook, Darrel; Wong, Jason; Grebely, Jason; Butt, Zahid A; Samji, Hasina; Ramji, Alnoor; Tyndall, Mark; Krajden, Mel

    2016-10-01

    Population-level monitoring of hepatitis C virus (HCV) infected people across the cascade of care identifies gaps in access and engagement in care and treatment. We characterized a population-level cascade of care for HCV in British Columbia (BC), Canada and identified factors associated with leakage at each stage. The BC Hepatitis Testers Cohort (BC-HTC) includes 1.5million individuals tested for HCV, HIV, reported cases of hepatitis B, and active tuberculosis in BC from 1990 to 2013 linked to medical visits, hospitalizations, cancers, prescription drugs and mortality data. We defined six HCV cascade of care stages: 1) estimated population prevalence; 2) HCV diagnosed; 3) HCV RNA tested; 4) genotyped; 5) initiated treatment; and 6) achieved sustained virologic response (SVR). We estimated that 73,203 people were HCV antibody positive in BC in 2012 (undiagnosed: 18,301, 25%; diagnosed: 54,902, 75%). Of these, 56%(40,656) had HCV RNA testing; 34%(26,300) were genotyped; 12%( 8532 ) had received interferon-based therapy and 7%(5197) had SVR. Males, older birth cohorts, and HBV coinfected were less likely to undergo HCV RNA testing. Among those with chronic HCV infection, 32% had received liver-related care. Retention in liver care was more likely in those with HIV, cirrhosis, and drug/alcohol use and less likely in males and HBV coinfected. Although there are gaps in HCV RNA testing and genotyping after HCV diagnosis, the major gap in the cascade of care was low treatment initiation. People with comorbidities progressed through the cascade of testing and care but few received treatment. Copyright © 2016. Published by Elsevier B.V.

  6. Impact assessment of cadmium contamination on rice (Oryza sativa L.) seedlings at molecular and population levels using multiple biomarkers.

    Science.gov (United States)

    Liu, Wan; Yang, Y S; Zhou, Q; Xie, L; Li, P; Sun, T

    2007-04-01

    Assessment of environmental contamination on ecology (plant) at molecular and population levels is important in risk quantification and remediation study. Random amplified polymorphic DNA (RAPD) assay and related other fingerprinting techniques have been employed to detect the genotoxin-induced DNA damage and mutations. This research compared the effects occurring at molecular and population levels in rice seedlings exposed to cadmium (Cd) concentrations of 15-60 mg l(-1) for 8 days with quartz sand culture. Inhibition of root growth and increase of total soluble protein content in root tips of rice seedlings were observed with the increase of Cd concentration. For the RAPD analyses, 12 RAPD primers of 50-70% GC content were found to produce unique polymorphic band patterns and subsequently were used to produce a total of 180 bands of 179-3056 bp in molecular size in the control root tips of rice seedlings. Results produced by these RAPD primers indicate that changes in RAPD profiles of root tips after Cd treatment include modifications in band intensity and gain or loss of bands by comparison with control. The effect of changes was dose-dependent. Genomic template stability compares favourably with the traditional indices such as root growth and soluble protein content. The DNA polymorphisms detected by RAPD analysis can be applied as a suitable biomarker assay for the detection of genotoxic effects of Cd contamination on plants.

  7. Launching a salt substitute to reduce blood pressure at the population level: a cluster randomized stepped wedge trial in Peru.

    Science.gov (United States)

    Bernabe-Ortiz, Antonio; Diez-Canseco, Francisco; Gilman, Robert H; Cárdenas, María K; Sacksteder, Katherine A; Miranda, J Jaime

    2014-03-25

    Controlling hypertension rates and maintaining normal blood pressure, particularly in resource-constrained settings, represent ongoing challenges of effective and affordable implementation in health care. One of the strategies being largely advocated to improve high blood pressure calls for salt reduction strategies. This study aims to estimate the impact of a population-level intervention based on sodium reduction and potassium increase - in practice, introducing a low-sodium, high-potassium salt substitute - on adult blood pressure levels. The proposed implementation research study includes two components: Phase 1, an exploratory component, and Phase 2, an intervention component. The exploratory component involves a triangle taste test and a formative research study designed to gain an understanding of the best implementation methods. Phase 2 involves a pragmatic stepped wedge trial design where the intervention will be progressively implemented in several clusters starting the intervention randomly at different times. In addition, we will evaluate the implementation strategy using a cost-effectiveness analysis. This is the first project in a Latin-American setting to implement a salt substitution intervention at the population level to tackle high blood pressure. Data generated and lessons learnt from this study will provide a strong platform to address potential interventions applicable to other similar low- and middle-income settings. This study is registered in ClinicalTrials.gov NCT01960972.

  8. Population-level lateralized aggressive and courtship displays make better fighters not lovers: evidence from a fly.

    Science.gov (United States)

    Benelli, Giovanni; Romano, Donato; Messing, Russell H; Canale, Angelo

    2015-06-01

    Lateralization (i.e., left-right asymmetries in the brain and behavior) of aggressive and courtship displays has been examined in many vertebrate species, while evidence for invertebrates is limited. We investigated lateralization of aggressive and courtship displays in a lekking tephritid species, the olive fruit fly, Bactrocera oleae. Results showed a left-biased population-level lateralization of aggressive displays, with no differences between the sexes. In both male-male and female-female contests, aggressive behaviors performed with left body parts led to greater fighting success than those performed with right body parts, while no differences in fighting duration were found. Olive fruit fly males also showed a side bias during courtship and mating behavior, courting females more frequently from the left than the right, front, or back sides. No differences were detected between courtship duration and copulation duration following the different male directional approaches. Male mating success was comparable whether females were approached from the left, right, front, or back side. Lateralized aggressive and courtship displays at the population-level may be connected to the prolonged social interactions occurring among lekking flies. Further research is needed on possible benefits arising from lateralization of courtship traits in insects. Copyright © 2015 Elsevier B.V. All rights reserved.

  9. The effects of swimming exercise and dissolved oxygen on growth performance, fin condition and precocious maturation of early-rearing Atlantic salmon Salmo salar

    Science.gov (United States)

    Waldrop, Thomas; Summerfelt, Steven T.; Mazik, Patricia M.; Good, Christopher

    2018-01-01

    Swimming exercise, typically measured in body-lengths per second (BL/s), and dissolved oxygen (DO), are important environmental variables in fish culture. While there is an obvious physiological association between these two parameters, their interaction has not been adequately studied in Atlantic salmon Salmo salar. Because exercise and DO are variables that can be easily manipulated in modern aquaculture systems, we sought to assess the impact of these parameters, alone and in combination, on the performance, health and welfare of juvenile Atlantic salmon. In our study, Atlantic salmon fry were stocked into 12 circular 0.5 m3 tanks in a flow-through system and exposed to either high (1.5–2 BL/s) or low (<0.5 BL/s) swimming speeding and high (100% saturation) or low (70% saturation) DO while being raised from 10 g to approximately 350 g in weight. Throughout the study period, we assessed the impacts of exercise and DO concentration on growth, feed conversion, survival and fin condition. By study's end, both increased swimming speed and higher DO were independently associated with a statistically significant increase in growth performance (p < .05); however, no significant differences were noted in survival and feed conversion. Caudal fin damage was associated with low DO, while right pectoral fin damage was associated with higher swimming speed. Finally, precocious male sexual maturation was associated with low swimming speed. These results suggest that providing exercise and dissolved oxygen at saturation during Atlantic salmon early rearing can result in improved growth performance and a lower incidence of precocious parr.

  10. Intestinal microbiota of healthy and unhealthy Atlantic salmon Salmo salar L. in a recirculating aquaculture system

    Science.gov (United States)

    Wang, Chun; Sun, Guoxiang; Li, Shuangshuang; Li, Xian; Liu, Ying

    2017-04-01

    The present study sampled the intestinal content of healthy and unhealthy Atlantic salmon (Salmo salar L.), the ambient water of unhealthy fish, and the biofilter material in the recirculating aquaculture system (RAS) to understand differences in the intestinal microbiota. The V4-V5 regions of the prokaryotic 16S rRNA genes in the samples were analyzed by MiSeq high-throughput sequencing. The fish were adults with no differences in body length or weight. Representative members of the intestinal microbiota were identified. The intestinal microbiota of the healthy fish included Proteobacteria (44.33%), Actinobacteria (17.89%), Bacteroidetes (15.25%), and Firmicutes (9.11%), among which the families Micrococcaceae and Oxalobacteraceae and genera Sphingomonas, Streptomyces, Pedobacter, Janthinobacterium, Burkholderia, and Balneimonas were most abundant. Proteobacteria (70.46%), Bacteroidetes (7.59%), and Firmicutes (7.55%) dominated the microbiota of unhealthy fish, and Chloroflexi (2.71%), and Aliivibrio and Vibrio as well as genera in the family Aeromonadaceae were most strongly represented. Overall, the intestinal hindgut microbiota differed between healthy and unhealthy fish. This study offers a useful tool for monitoring the health status of fish and for screening the utility of probiotics by studying the intestinal microbiota.

  11. Sulphated glycosaminoglycans and proteoglycans in the developing vertebral column of juvenile Atlantic salmon (Salmo salar).

    Science.gov (United States)

    Hannesson, Kirsten O; Ytteborg, Elisabeth; Takle, Harald; Enersen, Grethe; Bæverfjord, Grete; Pedersen, Mona E

    2015-08-01

    In the present study, the distribution of sulphated glycosaminoglycans (GAGs) in the developing vertebral column of Atlantic salmon (Salmo salar) at 700, 900, 1100 and 1400 d° was examined by light microscopy. The mineralization pattern was outlined by Alizarin red S and soft structures by Alcian blue. The temporal and spatial distribution patterns of different types of GAGs: chondroitin-4-sulphate/dermatan sulphate, chondroitin-6-sulphate, chondroitin-0-sulphate and keratan sulphate were addressed by immunohistochemistry using monoclonal antibodies against the different GAGs. The specific pattern obtained with the different antibodies suggests a unique role of the different GAG types in pattern formation and mineralization. In addition, the distribution of the different GAG types in normal and malformed vertebral columns from 15 g salmon was compared. A changed expression pattern of GAGs was found in the malformed vertebrae, indicating the involvement of these molecules during the pathogenesis. The molecular size of proteoglycans (PGs) in the vertebrae carrying GAGs was analysed with western blotting, and mRNA transcription of the PGs aggrecan, decorin, biglycan, fibromodulin and lumican by real-time qPCR. Our study reveals the importance of GAGs in development of vertebral column also in Atlantic salmon and indicates that a more comprehensive approach is necessary to completely understand the processes involved.

  12. Aluminum exposure impacts brain plasticity and behavior in Atlantic salmon (Salmo salar).

    Science.gov (United States)

    Grassie, C; Braithwaite, V A; Nilsson, J; Nilsen, T O; Teien, H-C; Handeland, S O; Stefansson, S O; Tronci, V; Gorissen, M; Flik, G; Ebbesson, L O E

    2013-08-15

    Aluminum (Al) toxicity occurs frequently in natural aquatic ecosystems as a result of acid deposition and natural weathering processes. Detrimental effects of Al toxicity on aquatic organisms are well known and can have consequences for survival. Fish exposed to Al in low pH waters will experience physiological and neuroendocrine changes that disrupt homeostasis and alter behavior. To investigate the effects of Al exposure on both the brain and behavior, Atlantic salmon (Salmo salar) kept in water treated with Al (pH 5.7, 0.37±0.04 μmol 1(-1) Al) for 2 weeks were compared with fish kept in under control conditions (pH 6.7, physiological stress, indicated by elevated plasma cortisol and glucose levels. Here we show for the first time that exposure to Al in acidic conditions also impaired learning performance in a maze task. Al toxicity also reduced the expression of NeuroD1 transcript levels in the forebrain of exposed fish. As in mammals, these data show that exposure to chronic stress, such as acidified Al, can reduce neural plasticity during behavioral challenges in salmon, and may impair the ability to cope with new environments.

  13. Differential metabolite levels in response to spawning-induced inappetence in Atlantic salmon Salmo salar.

    Science.gov (United States)

    Cipriano, Rocco C; Smith, McKenzie L; Vermeersch, Kathleen A; Dove, Alistair D M; Styczynski, Mark P

    2015-03-01

    Atlantic salmon Salmo salar undergo months-long inappetence during spawning, but it is not known whether this inappetence is a pathological state or one for which the fish are adapted. Recent work has shown that inappetent whale sharks can exhibit circulating metabolite profiles similar to ketosis known to occur in humans during starvation. In this work, metabolite profiling was used to explore differences in analyte profiles between a cohort of inappetent spawning run Atlantic salmon and captively reared animals that were fed up to and through the time of sampling. The two classes of animals were easily distinguished by their metabolite profiles. The sea-run fish had elevated ɷ-9 fatty acids relative to the domestic feeding animals, while other fatty acid concentrations were reduced. Sugar alcohols were generally elevated in inappetent animals, suggesting potentially novel metabolic responses or pathways in fish that feature these compounds. Compounds expected to indicate a pathological catabolic state were not more abundant in the sea-run fish, suggesting that the animals, while inappetent, were not stressed in an unnatural way. These findings demonstrate the power of discovery-based metabolomics for exploring biochemistry in poorly understood animal models. Copyright © 2015 Elsevier Inc. All rights reserved.

  14. Purification and characterization of biliverdin IXalpha from Atlantic salmon (Salmo salar) bile.

    Science.gov (United States)

    Ding, Z K; Xu, Y Q

    2002-08-01

    Biliverdin IXalpha was purified from the bile of Atlantic salmon (Salmo salar) using a silica gel (Wakogel C-200) column. The yield was 49.5 mg per 100 ml of fresh bile and purity 95.3%. The biliverdin IXalpha in the bile was quite stable when the bile was frozen at -80 degrees C for a period of 40 days. However, 7.1% of the biliverdin IXalpha was lost when the bile was stored at 4 degrees C for 20 days. The purified biliverdin IXalpha appeared as a single spot with Rf value of 0.25-0.27 on thin layer chromatography (TLC) and one main peak on high performance liquid chromatography (HPLC) at 436 or 650 nm. When the biliverdin IXalpha was subjected to enzymic reduction with highly purified biliverdin reductase, two clear isobestic points were seen, at 384 and 670 nm. When the products of the reaction with biliverdin IXalpha were extracted in butanol after completion of the reaction, one absorbance peak was observed at 468 nm. The time course of the reduction of biliverdin IXalpha to bilirubin IXalpha catalyzed by biliverdin reductase depended on reduced pyridine nucleotide. The time course of the NADPH-dependent reaction is different from that of the reaction with NADH. In the reduction of biliverdin IXalpha, per mole of biliverdin IXalpha reduced or per mole of bilirubin IXalpha formed 1 mole of reduced pyridine nucleotide was consumed in both the NADH and NADPH systems.

  15. Antibody against infectious salmon anaemia virus among feral Atlantic salmon (Salmo salar)

    Science.gov (United States)

    Cipriano, R.C.

    2009-01-01

    Archived sera from Atlantic salmon (Salmo salar) that returned to the Penobscot River (Maine), Merrimack River (Massachusetts), and Connecticut River (in Massachusetts) from 1995 to 2002 were analysed for antibodies against infectious salmon anaemia virus (ISAV) using an enzyme-linked immunosorbent assay (ELISA). Up to 60 samples were archived per river system per year. In a given year, the number of fish sampled by ELISA for ISAV antibodies in the Penobscot River ranged from 2.9 to 11.2, and the range of salmon sampled in the Merrimack River and the Connecticut River was 31.3-100 and 20.0-67.5, respectively. Archived sera were not available for the 1995 and 2002 year classes from the Connecticut River. In all, 1141 samples were processed; 14 serum samples tested positive for antibodies to ISAV. In the Penobscot River, serum from one fish tested positive in each of the 1995 and 1999 year-class returns, and sera from two fish tested positive in the 1998 returns. In the Merrimack River, sera from four fish tested positive in each of the 1996 and 1997 returns, and sera from two fish were positive in the 2002 return. None of the archived sera from Atlantic salmon that returned to the Connecticut River tested positive. ?? 2009 United States Government, Department of the Interior.

  16. Prokaryotic diversity and community composition in the Salar de Uyuni, a large scale, chaotropic salt flat.

    Science.gov (United States)

    dC Rubin, Sergio S; Marín, Irma; Gómez, Manuel J; Morales, Eduardo A; Zekker, Ivar; San Martín-Uriz, Patxi; Rodríguez, Nuria; Amils, Ricardo

    2017-09-01

    Salar de Uyuni (SdU), with a geological history that reflects 50 000 years of climate change, is the largest hypersaline salt flat on Earth and is estimated to be the biggest lithium reservoir in the world. Its salinity reaches saturation levels for NaCl, a kosmotropic salt, and high concentrations of MgCL2 and LiCl, both salts considered important chaotrophic stressors. In addition, extreme temperatures, anoxic conditions, high UV irradiance, high albedo and extremely low concentrations of phosphorous, make SdU a unique natural extreme environment in which to contrast hypotheses about limiting factors of life diversification. Geophysical studies of brines from different sampling stations show that water activity is rather constant along SdU. Geochemical measurements show significant differences in magnesium concentration, ranging from 0.2 to 2M. This work analyses the prokaryotic diversity and community structure at four SdU sampling stations, selected according to their location and ionic composition. Prokaryotic communities were composed of both Archaea (with members of the classes Halobacteria, Thermoplasmata and Nanohaloarchaea, from the Euryarchaeota and Nanohaloarcheota phyla respectively) and Bacteria (mainly belonging to Bacteroidetes and Proteobacteria phyla). The important differences in composition of microbial communities inversely correlate with Mg2+ concentration, suggesting that prokaryotic diversity at SdU is chaotropic dependent. © 2017 Society for Applied Microbiology and John Wiley & Sons Ltd.

  17. Reproductive performance of alternative male phenotypes of growth hormone transgenic Atlantic salmon (Salmo salar)

    Science.gov (United States)

    Moreau, Darek T R; Conway, Corinne; Fleming, Ian A

    2011-01-01

    Growth hormone (GH) transgenic Atlantic salmon (Salmo salar) is one of the first transgenic animals being considered for commercial farming, yet ecological and genetic concerns remain should they enter the wild and interact reproductively with wild fish. Here, we provide the first empirical data reporting on the breeding performance of GH transgenic Atlantic salmon males, including that of an alternative male reproductive phenotype (i.e. small, precocially mature parr), in pair-wise competitive trials within a naturalised stream mesocosm. Wild anadromous (i.e. large, migratory) males outperformed captively reared transgenic counterparts in terms of nest fidelity, quivering frequency and spawn participation. Similarly, despite displaying less aggression, captively reared nontransgenic mature parr were superior competitors to their transgenic counterparts in terms of nest fidelity and spawn participation. Moreover, nontransgenic parr had higher overall fertilisation success than transgenic parr, and their offspring were represented in more spawning trials. Although transgenic males displayed reduced breeding performance relative to nontransgenics, both male reproductive phenotypes demonstrated the ability to participate in natural spawning events and thus have the potential to contribute genes to subsequent generations. PMID:25568019

  18. Cardiomyopathy syndrome in Atlantic salmon Salmo salar L.: A review of the current state of knowledge.

    Science.gov (United States)

    Garseth, Å H; Fritsvold, C; Svendsen, J C; Bang Jensen, B; Mikalsen, A B

    2017-10-24

    Cardiomyopathy syndrome (CMS) is a severe cardiac disease affecting Atlantic salmon Salmo salar L. The disease was first recognized in farmed Atlantic salmon in Norway in 1985 and subsequently in farmed salmon in the Faroe Islands, Scotland and Ireland. CMS has also been described in wild Atlantic salmon in Norway. The demonstration of CMS as a transmissible disease in 2009, and the subsequent detection and initial characterization of piscine myocarditis virus (PMCV) in 2010 and 2011 were significant discoveries that gave new impetus to the CMS research. In Norway, CMS usually causes mortality in large salmon in ongrowing and broodfish farms, resulting in reduced fish welfare, significant management-related challenges and substantial economic losses. The disease thus has a significant impact on the Atlantic salmon farming industry. There is a need to gain further basic knowledge about the virus, the disease and its epidemiology, but also applied knowledge from the industry to enable the generation and implementation of effective prevention and control measures. This review summarizes the currently available, scientific information on CMS and PMCV with special focus on epidemiology and factors influencing the development of CMS. © 2017 The Authors. Journal of Fish Diseases Published by John Wiley & Sons Ltd.

  19. Daily rhythms in expression of genes of hepatic lipid metabolism in Atlantic salmon (Salmo salar L.).

    Science.gov (United States)

    Betancor, Mónica B; McStay, Elsbeth; Minghetti, Matteo; Migaud, Hervé; Tocher, Douglas R; Davie, Andrew

    2014-01-01

    In mammals, several genes involved in liver lipid and cholesterol homeostasis are rhythmically expressed with expression shown to be regulated by clock genes via Rev-erb 1α. In order to elucidate clock gene regulation of genes involved in lipid metabolism in Atlantic salmon (Salmo salar L.), the orphan nuclear receptor Rev-erb 1α was cloned and 24 h expression of clock genes, transcription factors and genes involved in cholesterol and lipid metabolism determined in liver of parr acclimated to a long-day photoperiod, which was previously shown to elicit rhythmic clock gene expression in the brain. Of the 31 genes analysed, significant daily expression was demonstrated in the clock gene Bmal1, transcription factor genes Srebp1, Lxr, Pparα and Pparγ, and several lipid metabolism genes Hmgcr, Ipi, ApoCII and El. The possible regulatory mechanisms and pathways, and the functional significance of these patterns of expression were discussed. Importantly and in contrast to mammals, Per1, Per2, Fas, Srebp2, Cyp71α and Rev-erb 1α did not display significant daily rhythmicity in salmon. The present study is the first report characterising 24 h profiles of gene expression in liver of Atlantic salmon. However, more importantly, the predominant role of lipids in the nutrition and metabolism of fish, and of feed efficiency in determining farming economics, means that daily rhythmicity in the regulation of lipid metabolism will be an area of considerable interest for future research in commercially important species.

  20. Structural and functional studies of STAT1 from Atlantic salmon (Salmo salar

    Directory of Open Access Journals (Sweden)

    Thim Hanna L

    2010-03-01

    Full Text Available Abstract Background Type I and type II interferons (IFNs exert their effects mainly through the JAK/STAT pathway, which is presently best described in mammals. STAT1 is involved in signaling pathways induced by both types of IFNs. It has a domain-like structure including an amino-terminus that stabilizes interaction between STAT dimers in a promoter-binding situation, a coiled coil domain facilitating interactions to other proteins, a central DNA-binding domain, a SH2 domain responsible for dimerization of phosphorylated STATs and conserved phosphorylation sites within the carboxy terminus. The latter is also the transcriptional activation domain. Results A salmon (Salmo salar STAT1 homologue, named ssSTAT1a, has been identified and was shown to be ubiquitously expressed in various cells and tissues. The ssSTAT1a had a domain-like structure with functional motifs that are similar to higher vertebrates. Endogenous STAT1 was shown to be phosphorylated at tyrosine residues both in salmon leukocytes and in TO cells treated with recombinant type I and type II IFNs. Also ectopically expressed ssSTAT1 was phosphorylated in salmon cells upon in vitro stimulation by the IFNs, confirming that the cloned gene was recognized by upstream tyrosine kinases. Treatment with IFNs led to nuclear translocation of STAT1 within one hour. The ability of salmon STAT1 to dimerize was also shown. Conclusions The structural and functional properties of salmon STAT1 resemble the properties of mammalian STAT1.

  1. Maladaptation and phenotypic mismatch in hatchery-reared Atlantic salmon Salmo salar released in the wild.

    Science.gov (United States)

    Stringwell, R; Lock, A; Stutchbury, C J; Baggett, E; Taylor, J; Gough, P J; Garcia de Leaniz, C

    2014-12-01

    Changes in body shape, fluctuating asymmetry (FA) and crypsis were compared among Atlantic salmon Salmo salar fry kept as controls in captivity and those released and subsequently recaptured in the wild according to a before-after-control-impact (BACI) design. Hatchery fish that survived in the wild became more cryptic and displayed a much lower incidence of fin erosion and of asymmetric individuals than control fish kept in captivity. Significant differences in body shape were also apparent, and survivors had longer heads, thicker caudal peduncles and a more streamlined body shape than hatchery controls as early as 20 days following stocking, most likely as a result of phenotypic plasticity and non-random, selective mortality of maladapted phenotypes. Hatchery-reared fish typically perform poorly in the wild and the results of this study indicate that this may be due to phenotypic mismatch, i.e. because hatcheries generate fish that are phenotypically mismatched to the natural environment. © 2014 The Fisheries Society of the British Isles.

  2. Paternal reproductive strategy influences metabolic capacities and muscle development of Atlantic salmon (Salmo salar L.) embryos.

    Science.gov (United States)

    Morasse, Sébastien; Guderley, Helga; Dodson, Julian J

    2008-01-01

    Male Atlantic salmon follow a conditional strategy, becoming either "combatants" that undertake a seaward migration and spend at least a year at sea or "sneakers" that remain in freshwater and mature as parr. A variety of physiological indices showed significant but small differences between the offspring of males that use these two reproductive tactics. Offspring fathered by anadromous male Atlantic salmon (Salmo salar L.) showed greater muscular development and muscle metabolic capacities but lower spontaneous movements than those fathered by mature male parr. At hatch and at maximum attainable wet weight (MAWW), offspring fathered by anadromous males had higher activities of mitochondrial (cytochrome C oxidase and citrate synthase) and glycolytic (lactate dehydrogenase [LDH]) enzymes than progeny of mature male parr. Enzymatic profiles of progeny of anadromous fathers also suggested greater nitrogen excretion capacity (glutamate dehydrogenase) and increased muscular development (creatine kinase and LDH) than in the progeny of mature parr. At MAWW, juveniles fathered by mature parr made considerably more spontaneous movements, presumably increasing their energy expenditures. For juveniles fathered by anadromous males, total cross-sectional areas of white and red muscle at hatch were higher due to the greater number of large-diameter fibers. We suggest that the slightly lower metabolic capacities and muscular development of alevins fathered by mature parr could reflect differences in energy partitioning during their dependence on vitellus. Greater spontaneous movements of offspring of mature male parr could favor feeding and growth after the resorption of the vitellus.

  3. Predicting the population-level impact of mitigating harbor porpoise bycatch with pingers and time-area fishing closures

    DEFF Research Database (Denmark)

    van Beest, Floris; Kindt-Larsen, Lotte; Bastardie, Francois

    2017-01-01

    efficiency) on the population size using the inner Danish waters as a biological system. The model incorporated empirical data on gillnet fishing effort and noise avoidance behavior by free-ranging harbor porpoises exposed to randomized high-frequency (20- to 160-kHz) pinger signals. The IBM simulations...... and protected marine top predator, involves the use of pingers (acoustic alarms that emit underwater noise) and time-area fishing closures. Although these mitigation measures can reduce harbor porpoise bycatch in gillnet fisheries considerably, inference about the long-term population-level consequences...... revealed a synergistic relationship between the implementation of time-area fishing closures and pinger deployment. Time-area fishing closures reduced bycatch rates substantially but not completely. In contrast, widespread pinger deployment resulted in total mitigation of bycatch but frequent and recurrent...

  4. Predicting the population-level impact of mitigating harbor porpoise bycatch with pingers and time-area fishing closures

    DEFF Research Database (Denmark)

    van Beest, Floris; Kindt-Larsen, Lotte; Bastardie, Francois

    2017-01-01

    and protected marine top predator, involves the use of pingers (acoustic alarms that emit underwater noise) and time-area fishing closures. Although these mitigation measures can reduce harbor porpoise bycatch in gillnet fisheries considerably, inference about the long-term population-level consequences...... is currently lacking. We developed a spatially explicit individual-based simulation model (IBM) with the aim to evaluate the effectiveness of these two bycatch mitigation measures. We quantified both the direct positive effects (i.e. reduced bycatch) as well as any indirect negative effects (i.e. reduced...... simulations revealed a synergistic relationship between the implementation of time-area fishing closures and pinger deployment. Time-area fishing closures reduced bycatch rates substantially but not completely. In contrast, widespread pinger deployment resulted in total mitigation of bycatch but frequent...

  5. Predicting the population-level impact of mitigating harbor porpoise bycatch with pingers and time-area fishing closures

    DEFF Research Database (Denmark)

    van Beest, Floris; Kindt-Larsen, Lotte; Bastardie, Francois

    2017-01-01

    and protected marine top predator, involves the use of pingers (acoustic alarms that emit underwater noise) and time-area fishing closures. Although these mitigation measures can reduce harbor porpoise bycatch in gillnet fisheries considerably, inference about the long-term population-level consequences...... noise avoidance behavior in high-quality foraging habitat negatively affected individual survival and the total population size. When both bycatch mitigation measures were implemented simultaneously, the negative impact of pinger noise-induced sub-lethal behavioral effects on the population was largely...... before enforcing their widespread implementation. Individual-based simulation models, such as the one presented here, offer an efficient and dynamic framework to evaluate the impact of human activities on the long-term survival of marine populations and can serve as a basis to design adaptive management...

  6. Monitoreo geoquímico de un sistema evaporítico natural: salar de Huasco (Chile

    Directory of Open Access Journals (Sweden)

    Ingrid Garcés Millas

    2010-01-01

    Full Text Available Se realizó un proceso de evaporación a escala de laboratorio con salmueras del Salar de Huasco, con el objeto de estudiar la pauta de evolución geoquímica y contrastarlo con el medio natural. La secuencia de precipitación obtenida fue calcita, yeso, thenardita y halita, minerales cuya presencia se comprobó mediante difractometría de rayos X. Estos resultados se corresponden con la sucesión de los estados de equilibrio que alcanzan las salmueras a lo largo de su progresiva concentración por evaporación, de acuerdo con los cálculos geoquímicos realizados con el código PHRQPITZ. La modelización geoquímica ha permitido comprobar que las situaciones de equilibrio se alcanzan en el dispositivo experimental en distintas etapas evolutivas a las observadas en el sistema natural. Este hecho se debe principalmente a dos factores, en primer lugar a la interacción de las soluciones diluidas de recarga del salar con la costra salina periférica rica en yeso, cuya disolución provoca alcanzar el equilibrio con esta fase mineralógica mucho antes en el sistema natural que en el laboratorio; y por otra, a la precipitación de mirabilita como consecuencia de las oscilaciones térmicas diarias, causantes de que el equilibrio con halita se alcance en el salar en una etapa evolutiva más avanzada que en el experimento, resultado del consumo de sodio, por precipitación de mirabilita.

  7. Reconstructing paleo-precipitation amounts using a terrestrial hydrologic model: Lake Titicaca and the Salar de Uyuni, Peru and Bolivia

    Science.gov (United States)

    Nunnery, J. A.; Baker, P. A.; Coe, M. T.; Fritz, S. C.

    2010-12-01

    The Peruvian/Bolivian Altiplano has provided many information-rich records bearing on the history of the South American summer monsoon (SASM), a large-scale circulation system that is responsible for much of the precipitation over the Amazon basin and the southern tropics and subtropics. Examples of these paleoclimate time series include long, drill core records from Lake Titicaca (extending back to ca. 400 Ka, Fritz et al., 2007), the long drill core record from Salar de Uyuni (> 250 Ka, Baker et al., 2001; Fritz et al., 2004), paleo-lake level records from the Salar de Uyuni (e.g. Bills et al., 2004; Placzek et al, 2006); drill core records from the Rio Desaguadero valley (Rigsby et al., 2003), and ice core records from Quelccaya, Illimani, and Sajama (Thompson et al., 2000; Ramirez et al., 2003). Several previous studies using energy and water balance models have been applied to these records in attempts to provide quantitative constraints on paleo-temperature and paleo-precipitation (e.g. Kessler, 1984; Hastenrath and Kutzbach, 1985; Cross et al, 2001; Rowe and Dunbar, 2004; Arnold, 2002; Blodgett et al., 1997). For example, Blodgett et al. concluded that high paleolake stands in the Bolivian Altiplano, dated at ca. 16,000 cal. Yr BP (Bills et al., 1994) required precipitation 20% higher than modern at temperatures 5°C colder than modern. However, their model did not take into account the major overflow from Lake Titicaca. Using the THMB hydrologic model, we show that overflow from Lake Titicaca is necessary to produce and sustain large lakes in the Salar de Uyuni basin. This hydrological connection (via the Rio Desaguadero) between the northern and southern Altiplano likely was only established about 60,000 years ago. Prior to that, there were no sustained, large and deep paleolakes on the southern Altiplano. Rather, drill core evidence indicates a very long sequence of shallow, hypersaline lakes and playas.

  8. The impact of water exchange rate and treatment processes on water-borne hormones in recirculation aquaculture systems containing sexually maturing Atlantic salmon Salmo salar

    Science.gov (United States)

    A controlled seven-month study was conducted in six replicated water recirculation aquaculture systems (WRAS) to assess post-smolt Atlantic salmon (Salmo salar) performance in relation to WRAS water exchange rate. Unexpectedly high numbers of precocious sexually mature fish were observed in all WRAS...

  9. Fillet quality and processing attributes of postsmolt Atlantic salmon, Salmo salar, fed a fishmeal-free diet and a fishmeal-based diet in recirculation aquaculture systems

    Science.gov (United States)

    Many studies have evaluated the adequacy of alternate ingredient diets for Atlantic salmon, Salmo salar, mainly with focus on fish performance and health; however, comprehensive analysis of fillet quality is lacking, particularly for salmon fed these diets in recirculation aquaculture systems (RAS)....

  10. Passing a seawater challenge test is not indicative of hatchery-reared Atlantic salmon Salmo salar smolts performing as well at sea as their naturally produced conspecifics.

    Science.gov (United States)

    Jensen, A J; Berg, M; Bremset, G; Finstad, B; Hvidsten, N A; Jensås, J G; Johnsen, B O; Lund, E

    2016-06-01

    Despite satisfactory reactions to seawater challenge tests indicative of appropriate physiological state, hatchery-reared Atlantic salmon Salmo salar smolts stocked in the Eira River in Norway between 2001 and 2011 performed less well at sea in terms of growth, age at maturity and survival than smolts of natural origin. The mean rates of return to the river for hatchery-reared and naturally produced S. salar were 0·98 and 2·35%. In the Eira River, c. 50 000 hatchery-reared S. salar smolts of local origin were stocked annually to compensate for reduced natural smolt production following regulation for hydroelectric purposes, while a mean of 17 262 smolts were produced naturally in the river. This study demonstrates that, although captive S. salar perform well in seawater challenge tests, hatchery-reared smolts are not necessarily as adaptable to marine life as their naturally produced counterparts. These findings suggest that production of hatchery-reared smolts more similar to naturally produced individuals in morphology, physiology and behaviour will be necessary to improve success of hatchery releases. Where possible, supplementary or alternative measures, including habitat restoration, could be implemented to ensure the long-term viability of wild stocks. © 2016 The Fisheries Society of the British Isles.

  11. Assessment of interbreeding and introgression of farm genes into a small Scottish Atlantic salmon Salmo salar stock: ad hoc samples - ad hoc results?

    Science.gov (United States)

    Verspoor, E; Knox, D; Marshall, S

    2016-12-01

    An eclectic set of tissues and existing data, including purposely collected samples, spanning 1997-2006, was used in an ad hoc assessment of hybridization and introgression of farmed wild Atlantic salmon Salmo salar in the small Loch na Thull (LnT) catchment in north-west Scotland. The catchment is in an area of marine farm production and contains freshwater smolt rearing cages. The LnT S. salar stock was found to be genetically distinctive from stocks in neighbouring rivers and, despite regular reports of feral farm S. salar, there was no evidence of physical or genetic mixing. This cannot be completely ruled out, however, and low level mixing with other local wild stocks has been suggested. The LnT population appeared underpinned by relatively smaller effective number of breeders (Neb ) and showed relatively low levels of genetic diversity, consistent with a small effective population size. Small sample sizes, an incomplete farm baseline and the use of non-diagnostic molecular markers, constrain the power of the analysis but the findings strongly support the LnT catchment having a genetically distinct wild S. salar population little affected by interbreeding with feral farm escapes. © 2016 The Fisheries Society of the British Isles.

  12. Comparative cardiac pathological changes of Atlantic salmon (Salmo salar L.) affected with heart and skeletal muscle inflammation (HSMI), cardiomyopathy syndrome (CMS) and pancreas disease (PD)

    DEFF Research Database (Denmark)

    Yousaf, Muhammad Naveed; Koppang, Erling Olaf; Skjødt, Karsten

    2013-01-01

    The heart is considered the powerhouse of the cardiovascular system. Heart and skeletal muscle inflammation (HSMI), cardiomyopathy syndrome (CMS) and pancreas disease (PD) are cardiac diseases of marine farmed Atlantic salmon (Salmo salar) which commonly affect the heart in addition to the skeletal...

  13. Replacement of dietary soy- with air classified faba bean protein concentrate alters the hepatic transcriptome in Atlantic salmon (Salmo salar) parr.

    Science.gov (United States)

    De Santis, Christian; Crampton, Viv O; Bicskei, Beatrix; Tocher, Douglas R

    2015-12-01

    The production of carnivorous fish such as Atlantic salmon (Salmo salar) is dependent on the availability of high quality proteins for feed formulations. For a number of nutritional, strategic and economic reasons, the use of plant proteins has steadily increased over the years, however a major limitation is associated with the presence of anti-nutritional factors and the nutritional profile of the protein concentrate. Investigating novel raw materials involves understanding the physiological consequences associated with the dietary inclusion of protein concentrates. The primary aim of the present study was to assess the metabolic response of salmon to increasing inclusion of air-classified faba bean protein concentrate (BPC) in feeds as a replacement for soy protein concentrate (SPC). Specifically, we tested treatments with identical contents of fishmeal (222.4gkg(-1)) and progressively higher inclusion of BPC (0gkg(-1), 111.8gkg(-1), 223.6gkg(-1), 335.4gkg(-1), 447.2gkg(-1)) substituting SPC. This study demonstrated a dose-dependent metabolic response to a plant ingredient and was the first to compare the nutrigenomic transcriptional responses after substitution of terrestrial feed ingredients such as BPC and SPC without withdrawal of marine ingredients. It was found that after eight weeks a major physiological response in liver was only evident above 335.4gkg(-1) BPC and included decreased expression of metabolic pathways, and increased expression of genes regulating transcription and translation processes and the innate immune response. Furthermore, we showed that the nutritional stress caused by BPC resembled, at least at hepatic transcriptional level, that caused by soybean meal (included as a positive control in our experimental design). The outcomes of the present study suggested that Atlantic salmon parr might efficiently utilize moderate substitution of dietary SPC with BPC, with the optimum inclusion level being around 120gkg(-1)in the type of feeds

  14. Basin-scale phenology and effects of climate variability on global timing of initial seaward migration of Atlantic salmon (Salmo salar).

    Science.gov (United States)

    Otero, Jaime; L'Abée-Lund, Jan Henning; Castro-Santos, Ted; Leonardsson, Kjell; Storvik, Geir O; Jonsson, Bror; Dempson, Brian; Russell, Ian C; Jensen, Arne J; Baglinière, Jean-Luc; Dionne, Mélanie; Armstrong, John D; Romakkaniemi, Atso; Letcher, Benjamin H; Kocik, John F; Erkinaro, Jaakko; Poole, Russell; Rogan, Ger; Lundqvist, Hans; Maclean, Julian C; Jokikokko, Erkki; Arnekleiv, Jo Vegar; Kennedy, Richard J; Niemelä, Eero; Caballero, Pablo; Music, Paul A; Antonsson, Thorolfur; Gudjonsson, Sigurdur; Veselov, Alexey E; Lamberg, Anders; Groom, Steve; Taylor, Benjamin H; Taberner, Malcolm; Dillane, Mary; Arnason, Fridthjofur; Horton, Gregg; Hvidsten, Nils A; Jonsson, Ingi R; Jonsson, Nina; McKelvey, Simon; Naesje, Tor F; Skaala, Oystein; Smith, Gordon W; Saegrov, Harald; Stenseth, Nils C; Vøllestad, Leif Asbjørn

    2014-01-01

    Migrations between different habitats are key events in the lives of many organisms. Such movements involve annually recurring travel over long distances usually triggered by seasonal changes in the environment. Often, the migration is associated with travel to or from reproduction areas to regions of growth. Young anadromous Atlantic salmon (Salmo salar) emigrate from freshwater nursery areas during spring and early summer to feed and grow in the North Atlantic Ocean. The transition from the freshwater ('parr') stage to the migratory stage where they descend streams and enter salt water ('smolt') is characterized by morphological, physiological and behavioural changes where the timing of this parr-smolt transition is cued by photoperiod and water temperature. Environmental conditions in the freshwater habitat control the downstream migration and contribute to within- and among-river variation in migratory timing. Moreover, the timing of the freshwater emigration has likely evolved to meet environmental conditions in the ocean as these affect growth and survival of the post-smolts. Using generalized additive mixed-effects modelling, we analysed spatio-temporal variations in the dates of downstream smolt migration in 67 rivers throughout the North Atlantic during the last five decades and found that migrations were earlier in populations in the east than the west. After accounting for this spatial effect, the initiation of the downstream migration among rivers was positively associated with freshwater temperatures, up to about 10 °C and levelling off at higher values, and with sea-surface temperatures. Earlier migration occurred when river discharge levels were low but increasing. On average, the initiation of the smolt seaward migration has occurred 2.5 days earlier per decade throughout the basin of the North Atlantic. This shift in phenology matches changes in air, river, and ocean temperatures, suggesting that Atlantic salmon emigration is responding to the

  15. Investigations on the effect of high surface albedo on erythemally effective UV irradiance: results of a campaign at the Salar de Uyuni, Bolivia.

    Science.gov (United States)

    Reuder, Joachim; Ghezzi, Flavio; Palenque, Eduardo; Torrez, Rene; Andrade, Marco; Zaratti, Francesco

    2007-04-02

    Measurements and model calculations have been performed to study the effect of high surface albedo on erythemally effective UV irradiance. A central part of the investigation has been a one week measurement campaign at Salar de Uyuni in the Southern part of the Bolivian Altiplano. The Salar de Uyuni, the largest salt lake of the world, is characterized by largely homogeneous surface conditions during most of the year. Albedo measurements performed by an UV radiometer result in a reflectivity for erythemally effective radiation of 0.69+/-0.02. The measurements show hardly any dependency on solar elevation, indicating the homogeneity of the surface and nearly isotropic reflection properties of the Salar. The effects of the high albedo surface on the erythemally effective irradiance, i.e. the UV index (UVI), has been experimentally determined by simultaneous measurements of several UV radiometers located at different sites around and on the Salar. In this context a method for the minimization of systematic deviations between the individual detectors used for the investigation is presented. It ensures the intercomparability of the performed UV measurements within +/-2% which is a distinct improvement compared to the typical absolute accuracy of UV irradiance measurements in the order of +/-5%. For solar elevations around 50 degrees the UVI measured close to the center of the Salar is typically enhanced by 20% compared to the values determined outside. Towards lower solar elevations this increase becomes slightly weaker. The measurements agree well with both, own corresponding 1D and previously published 3D radiative transfer calculations from literature.

  16. Dose-dependent hepatic transcriptional responses in Atlantic salmon (Salmo salar) exposed to sublethal doses of gamma radiation

    Energy Technology Data Exchange (ETDEWEB)

    Song, You, E-mail: you.song@niva.no [Norwegian University of Life Sciences (NMBU), Faculty of Environmental Science and Technology, Department of Environmental Sciences (IMV), Centre for Environmental Radioactivity - CERAD, P.O. Box 5003, N-1432 Ås (Norway); Norwegian Institute for Water Research (NIVA), Gaustadalléen 21, N-0349 Oslo (Norway); Salbu, Brit; Teien, Hans-Christian; Heier, Lene Sørlie [Norwegian University of Life Sciences (NMBU), Faculty of Environmental Science and Technology, Department of Environmental Sciences (IMV), Centre for Environmental Radioactivity - CERAD, P.O. Box 5003, N-1432 Ås (Norway); Rosseland, Bjørn Olav [Norwegian University of Life Sciences (NMBU), Faculty of Environmental Science and Technology, Department of Environmental Sciences (IMV), Centre for Environmental Radioactivity - CERAD, P.O. Box 5003, N-1432 Ås (Norway); Norwegian University of Life Sciences (NMBU), Department of Ecology and Natural Resource Management, P.O. Box 5003, N-1432 Ås (Norway); Tollefsen, Knut Erik [Norwegian University of Life Sciences (NMBU), Faculty of Environmental Science and Technology, Department of Environmental Sciences (IMV), Centre for Environmental Radioactivity - CERAD, P.O. Box 5003, N-1432 Ås (Norway); Norwegian Institute for Water Research (NIVA), Gaustadalléen 21, N-0349 Oslo (Norway)

    2014-11-15

    Highlights: • First study on early stress responses in salmon exposed to low-dose gamma radiation. • Dramatic dose-dependent transcriptional responses characterized. • Multiple modes of action proposed for gamma radiation. - Abstract: Due to the production of free radicals, gamma radiation may pose a hazard to living organisms. The high-dose radiation effects have been extensively studied, whereas the ecotoxicity data on low-dose gamma radiation is still limited. The present study was therefore performed using Atlantic salmon (Salmo salar) to characterize effects of low-dose (15, 70 and 280 mGy) gamma radiation after short-term (48 h) exposure. Global transcriptional changes were studied using a combination of high-density oligonucleotide microarrays and quantitative real-time reverse transcription polymerase chain reaction (qPCR). Differentially expressed genes (DEGs; in this article the phrase gene expression is taken as a synonym of gene transcription, although it is acknowledged that gene expression can also be regulated, e.g., at protein stability and translational level) were determined and linked to their biological meanings predicted using both Gene Ontology (GO) and mammalian ortholog-based functional analyses. The plasma glucose level was also measured as a general stress biomarker at the organism level. Results from the microarray analysis revealed a dose-dependent pattern of global transcriptional responses, with 222, 495 and 909 DEGs regulated by 15, 70 and 280 mGy gamma radiation, respectively. Among these DEGs, only 34 were commonly regulated by all radiation doses, whereas the majority of differences were dose-specific. No GO functions were identified at low or medium doses, but repression of DEGs associated with GO functions such as DNA replication, cell cycle regulation and response to reactive oxygen species (ROS) were observed after 280 mGy gamma exposure. Ortholog-based toxicity pathway analysis further showed that 15 mGy radiation

  17. Growth and osmoregulation in Salmo salar L. juveniles 1+, 1½ + and 2+ reared under restrained salinity

    Directory of Open Access Journals (Sweden)

    José Fernando Magalhães Gonçalves

    2013-02-01

    Full Text Available The freshwater phase of Atlantic salmon Salmo salar L vary between one and eight years. The reduction of the freshwater phase is desirable to reduce freshwater usage, human resources and to increase year round availability of pan-sized salmon. Three trials were conducted to investigate the possibility of supply the market in a year-round basis, with pan-sized Atlantic salmon Salmo salar L. (250-300 g in Portugal (southern limit of the natural distribution of this species. This study primarily aimed to compare the osmoregulatory ability and growth of different fish sizes, smolts 1+ (trial 1, 1.5+ (trial 2 and 2+ (trial 3, in freshwater and seawater conditions. Additionally, effects of photoperiod were determined in smolts 1.5+ (trial 2 for both freshwater and seawater groups. The increments in the plasma osmolality and chlorine concentrations after seawater transfer suggest an identical development in the hypo-osmoregulation capacity among the different age classes. In all trials, weight gain was smaller after 30 d of saltwater transfer when compared to fish reared in freshwater. However, the growth depression was temporary. Seawater group showed a compensatory growth in the immediate months, which permitted an improvement in growth rates. At the end of trials there were minor differences on growth performance between freshwater and seawater groups. Specific growth rates varied between 0.7 and 1.0 % day-1, according to the age and /or size and transfer season.

  18. Effects of GnRHa treatment during vitellogenesis on the reproductive physiology of thermally challenged female Atlantic salmon (Salmo salar

    Directory of Open Access Journals (Sweden)

    Kelli Anderson

    2017-10-01

    Full Text Available Tasmanian Atlantic salmon (S. salar broodstock can experience temperatures above 20 °C, which impairs reproductive development and inhibits ovulation. The present study investigated the prolonged use of gonadotropin releasing hormone analogue (GnRHa during vitellogenesis as a means of maintaining endocrine function and promoting egg quality at elevated temperature in maiden and repeat spawning S. salar. GnRHa-treatment during vitellogenesis did not compensate for the negative effects of thermal challenge on the timing of ovulation, egg size, egg fertility or embryo survival in any fish maintained at 22 °C relative to 14 °C. The lack of effectiveness was reflected by the endocrine data, as plasma follicle stimulating hormone and luteinising hormone levels were not different between treated and untreated groups at 22 °C. Furthermore, plasma testosterone and E2 levels were unchanged in GnRHa-treated fish at 22 °C, and plasma levels were generally lower in both groups maintained at 22 °C relative to 14 °C. Transcription of vitellogenin, and zona pellucida B and C was not enhanced in GnRHa-treated fish relative to untreated fish at 22 °C, presumably due to observed suppression of plasma E2. These results indicate that thermal impairment of reproduction is likely to occur on multiple levels, and is difficult to overcome via hormonal manipulation.

  19. Effects of GnRHa treatment during vitellogenesis on the reproductive physiology of thermally challenged female Atlantic salmon (Salmo salar).

    Science.gov (United States)

    Anderson, Kelli; Pankhurst, Ned; King, Harry; Elizur, Abigail

    2017-01-01

    Tasmanian Atlantic salmon (S. salar) broodstock can experience temperatures above 20 °C, which impairs reproductive development and inhibits ovulation. The present study investigated the prolonged use of gonadotropin releasing hormone analogue (GnRHa) during vitellogenesis as a means of maintaining endocrine function and promoting egg quality at elevated temperature in maiden and repeat spawning S. salar. GnRHa-treatment during vitellogenesis did not compensate for the negative effects of thermal challenge on the timing of ovulation, egg size, egg fertility or embryo survival in any fish maintained at 22 °C relative to 14 °C. The lack of effectiveness was reflected by the endocrine data, as plasma follicle stimulating hormone and luteinising hormone levels were not different between treated and untreated groups at 22 °C. Furthermore, plasma testosterone and E2 levels were unchanged in GnRHa-treated fish at 22 °C, and plasma levels were generally lower in both groups maintained at 22 °C relative to 14 °C. Transcription of vitellogenin, and zona pellucida B and C was not enhanced in GnRHa-treated fish relative to untreated fish at 22 °C, presumably due to observed suppression of plasma E2. These results indicate that thermal impairment of reproduction is likely to occur on multiple levels, and is difficult to overcome via hormonal manipulation.

  20. Effects of feeding regimes and early maturation on migratory behaviour of landlocked hatchery-reared Atlantic salmon Salmo salar smolts.

    Science.gov (United States)

    Norrgård, J R; Bergman, E; Schmitz, M; Greenberg, L A

    2014-10-01

    The migratory behaviour of hatchery-reared landlocked Atlantic salmon Salmo salar raised under three different feeding regimes was monitored through the lower part of the River Klarälven, Sweden. The smolts were implanted with acoustic transmitters and released into the River Klarälven, 25 km upstream of the outlet in Lake Vänern. Early mature males, which had matured the previous autumn, were also tagged and released. To monitor migration of the fish, acoustic receivers were deployed along the migratory route. The proportion of S. salar that reached Lake Vänern was significantly greater for fish fed fat-reduced feed than for fish given rations with higher fat content, regardless of ration size. Fish from the early mature male group remained in the river to a greater extent than fish from the three feeding regimes. Smolt status (degree of silvering), as visually assessed, did not differ among the feeding regime groups, and moreover, fully-silvered fish, regardless of feeding regime, migrated faster and had a greater migration success than fish with less developed smolt characteristics. Also, successful migrants had a lower condition factor than unsuccessful ones. These results indicate that the migration success of hatchery-reared S. smolts released to the wild can be enhanced by relatively simple changes in feeding regimes and by matching stocking time with smolt development. © 2014 The Fisheries Society of the British Isles.

  1. A Polyprotein-Expressing Salmonid Alphavirus Replicon Induces Modest Protection in Atlantic Salmon (Salmo Salar Against Infectious Pancreatic Necrosis

    Directory of Open Access Journals (Sweden)

    Azila Abdullah

    2015-01-01

    Full Text Available Vaccination is an important strategy for the control and prevention of infectious pancreatic necrosis (IPN in farmed Atlantic salmon (Salmo salar in the post-smolt stage in sea-water. In this study, a heterologous gene expression system, based on a replicon construct of salmonid alphavirus (SAV, was used for in vitro and in vivo expression of IPN virus proteins. The large open reading frame of segment A, encoding the polyprotein NH2-pVP2-VP4-VP3-COOH, as well as pVP2, were cloned and expressed by the SAV replicon in Chinook salmon embryo cells (CHSE-214 and epithelioma papulosum cyprini (EPC cells. The replicon constructs pSAV/polyprotein (pSAV/PP and pSAV/pVP2 were used to immunize Atlantic salmon (Salmo salar by a single intramuscular injection and tested in a subsequent IPN virus (IPNV challenge trial. A low to moderate protection against IPN was observed in fish immunized with the replicon vaccine that encoded the pSAV/PP, while the pSAV/pVP2 construct was not found to induce protection.

  2. Transcriptional responses in Atlantic salmon (Salmo salar) exposed to deltamethrin, alone or in combination with azamethiphos.

    Science.gov (United States)

    Olsvik, Pål A; Ørnsrud, Robin; Lunestad, Bjørn Tore; Steine, Nils; Fredriksen, Børge Nilsen

    2014-05-01

    Recently, Atlantic salmon (Salmo salar) fish farmers have applied a combination of deltamethrin and azamethiphos in high-concentration and short-duration immersion treatment to improve protection against sea-lice (Lepeophtheirus sp.). In this work we aimed to study the effects of deltamethrin, alone or in combination with azamethiphos, on the transcription of stress and detoxification marker genes. Atlantic salmon kept at 12°C (one group was also kept at 4-5°C) were treated with deltamethrin alone or in combination with azamethiphos for a total of 40min, and gill and liver tissue harvested for transcriptional analysis 2 and 24h post treatment. No lethality was observed during the experiment. The result showed that deltamethrin, alone or in combination with azamethiphos, affected the transcriptional levels of several oxidative stress markers, including MnSOD (SOD2) and HSP70 (HSPA8) in the liver, and GPX1, CAT, MnSOD, HSP70 and GSTP1 in the gills. Significant responses for CASP3B, BCLX, IGFBP1B and ATP1A1 (Na-K-ATPase a1b) by some of the treatments suggest that the pharmaceutical drugs may affect apoptosis, growth and ion regulation mechanisms. In fish kept at 4-5°C, different effects were observed, suggesting a temperature-dependent response. In conclusion, the observed responses indicate that short-term exposure to deltamethrin has a profound effect on transcription of the evaluated markers in gills and liver of fish. Co-treatment with azamethiphos appears to have small mitigating effects on the transcriptional response caused by deltamethrin exposure alone. Copyright © 2014 Elsevier Inc. All rights reserved.

  3. Inflammatory responses in primary muscle cell cultures in Atlantic salmon (Salmo salar).

    Science.gov (United States)

    Pooley, Nicholas J; Tacchi, Luca; Secombes, Christopher J; Martin, Samuel A M

    2013-11-01

    The relationship between fish health and muscle growth is critical for continued expansion of the aquaculture industry. The effect of immune stimulation on the expression of genes related to the energy balance of fish is poorly understood. In mammals immune stimulation results in major transcriptional changes in muscle, potentially to allow a reallocation of amino acids for use in the immune response and energy homeostasis. The aim of this study was to investigate the effects of immune stimulation on fish muscle gene expression. Atlantic salmon (Salmo salar) primary muscle cell cultures were stimulated with recombinant (r)IL-1β, a major proinflammatory cytokine, for 24 h in order to simulate an acute immune response. The transcriptomic response was determined by RNA hybridization to a 4 × 44 K Agilent Atlantic salmon microarray platform. The rIL-1β stimulation induced the expression of genes related to both the innate and adaptive immune systems. In addition there were highly significant changes in the expression of genes related to regulation of the cell cycle, growth/structural proteins, proteolysis and lipid metabolism. Of interest were a number of IGF binding proteins that were differentially expressed, which may demonstrate cross talk between the growth and immune systems. We show rIL-1β modulates the expression of not only immune related genes, but also that of genes involved in processes related to growth and metabolism. Co-stimulation of muscle cells with both rIGF-I and rIL-1β demonstrates cross talk between these pathways providing potential avenues for further research. This study highlights the potential negative effects of inflammation on muscle protein deposition and growth in fish and extends our understanding of energy allocation in ectothermic animals.

  4. Water contaminated with Didymosphenia geminata generates changes in Salmo salar spermatozoa activation times.

    Science.gov (United States)

    Olivares, Pamela; Orellana, Paola; Guerra, Guillermo; Peredo-Parada, Matías; Chavez, Viviana; Ramirez, Alfredo; Parodi, Jorge

    2015-06-01

    Didimosphenia geminata ("didymo"), has become a powerful and devastating river plague in Chile. A system was developed in D. geminata channels with the purpose evaluating the effects of water polluted with didymo on the activation of Atlantic salmon (Salmo salar) spermatozoa. Results indicate that semen, when activated with uncontaminated river water had an average time of 60±21s. When using Powermilt, (a commercial activator), times of 240±21s are achieved, while rivers contaminated with D. geminata achieve a motility time of 30±12s. Interestingly enough, the kinetic parameters of VSL, VCL and VAP showed no significant changes under all of the conditions. Furthermore, the presence of D. geminata reduces activation time of the samples as the cells age, indicating increased effects in spermatozoa that are conserved for more than 5 days. D. geminata has antioxidant content, represented by polyphenols; 200ppm of polyphenol were obtained in this study per 10g of microalgae. Spermatozoa exposed to these extracts showed a reduction in mobility time in a dose dependent manner, showing an IC50 of 15ppm. The results suggest an effect on spermatozoa activation, possibly due to the release of polyphenols present in contaminated rivers, facilitating the alteration of sperm motility times, without affecting the viability or kinetics of the cells. These findings have important implications for current policy regarding the control of the algae. Current control measures focus on the number of visible species, and not on the compounds that they release, which this study shows, also have a problematic effect on salmon production. Copyright © 2015 Elsevier B.V. All rights reserved.

  5. Daily rhythms in expression of genes of hepatic lipid metabolism in Atlantic salmon (Salmo salar L..

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    Mónica B Betancor

    Full Text Available In mammals, several genes involved in liver lipid and cholesterol homeostasis are rhythmically expressed with expression shown to be regulated by clock genes via Rev-erb 1α. In order to elucidate clock gene regulation of genes involved in lipid metabolism in Atlantic salmon (Salmo salar L., the orphan nuclear receptor Rev-erb 1α was cloned and 24 h expression of clock genes, transcription factors and genes involved in cholesterol and lipid metabolism determined in liver of parr acclimated to a long-day photoperiod, which was previously shown to elicit rhythmic clock gene expression in the brain. Of the 31 genes analysed, significant daily expression was demonstrated in the clock gene Bmal1, transcription factor genes Srebp1, Lxr, Pparα and Pparγ, and several lipid metabolism genes Hmgcr, Ipi, ApoCII and El. The possible regulatory mechanisms and pathways, and the functional significance of these patterns of expression were discussed. Importantly and in contrast to mammals, Per1, Per2, Fas, Srebp2, Cyp71α and Rev-erb 1α did not display significant daily rhythmicity in salmon. The present study is the first report characterising 24 h profiles of gene expression in liver of Atlantic salmon. However, more importantly, the predominant role of lipids in the nutrition and metabolism of fish, and of feed efficiency in determining farming economics, means that daily rhythmicity in the regulation of lipid metabolism will be an area of considerable interest for future research in commercially important species.

  6. The Skin-Mucus Microbial Community of Farmed Atlantic Salmon (Salmo salar

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    Giusi Minniti

    2017-10-01

    Full Text Available The skin of the teleost is a flexible and scaled structure that protects the fish toward the external environment. The outermost surface of the skin is coated with mucus, which is believed to be colonized by a diverse bacterial community (commensal and/or opportunistic. Little is known about such communities and their role in fish welfare. In aquaculture, fish seem to be more susceptible to pathogens compared to wild fish. Indeed common fish farming practices may play important roles in promoting their vulnerability, possibly by causing changes to their microbiomes. In the present study, 16S rRNA gene amplicon sequencing was employed to analyze the composition of the farmed Salmo salar skin-mucus microbiome before and after netting and transfer. The composition of the bacterial community present in the rearing water was also investigated in order to evaluate its correlation with the community present on the fish skin. Our results reveal variability of the skin-mucus microbiome among the biological replicates before fish handling. On the contrary, after fish handling, the skin-mucus community exhibited structural similarity among the biological replicates and significant changes were observed in the bacterial composition compared to the fish analyzed prior to netting and transfer. Limited correlation was revealed between the skin-mucus microbiome and the bacterial community present in the rearing water. Finally, analysis of skin-mucus bacterial biomasses indicated low abundance for some samples, highlighting the need of caution when interpreting community data due to the possible contamination of water-residing bacteria.

  7. Comparative responses to endocrine disrupting compounds in early life stages of Atlantic salmon, Salmo salar

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    Duffy, Tara A.; Iwanowicz, Luke R.; McCormick, Stephen D.

    2014-01-01

    Atlantic salmon (Salmo salar) are endangered anadromous fish that may be exposed to feminizing endocrine disrupting compounds (EDCs) during early development, potentially altering physiological capacities, survival and fitness. To assess differential life stage sensitivity to common EDCs, we carried out short-term (four day) exposures using three doses each of 17α-ethinylestradiol (EE2), 17β-estradiol (E2), and nonylphenol (NP) on four early life stages; embryos, yolk-sac larvae, feeding fry and one year old smolts. Differential response was compared using vitellogenin (Vtg, a precursor egg protein) gene transcription. Smolts were also examined for impacts on plasma Vtg, cortisol, thyroid hormones (T4/T3) and hepatosomatic index (HSI). Compound-related mortality was not observed in any life stage, but Vtg mRNA was elevated in a dose-dependent manner in yolk-sac larvae, fry and smolts but not in embyos. The estrogens EE2 and E2 were consistently stronger inducers of Vtg than NP. Embryos responded significantly to the highest concentration of EE2 only, while older life stages responded to the highest doses of all three compounds, as well as intermediate doses of EE2 and E2. Maximal transcription was greater for fry among the three earliest life stages, suggesting fry may be the most responsive life stage in early development. Smolt plasma Vtg was also significantly increased, and this response was observed at lower doses of each compound than was detected by gene transcription suggesting this is a more sensitive indicator at this life stage. HSI was increased at the highest doses of EE2 and E2 and plasma T3 decreased at the highest dose of EE2. Our results indicate that all life stages after hatching are potentially sensitive to endocrine disruption by estrogenic compounds and that physiological responses were altered over a short window of exposure, indicating the potential for these compounds to impact fish in the wild.

  8. Simulation to aid in interpreting biological relevance and setting of population-level protection goals for risk assessment of pesticides.

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    Topping, Christopher John; Luttik, Robert

    2017-10-01

    Specific protection goals (SPGs) comprise an explicit expression of the environmental components that need protection and the maximum impacts that can be tolerated. SPGs are set by risk managers and are typically based on protecting populations or functions. However, the measurable endpoints available to risk managers, at least for vertebrates, are typically laboratory tests. We demonstrate, using the example of eggshell thinning in skylarks, how simulation can be used to place laboratory endpoints in context of population-level effects as an aid to setting the SPGs. We develop explanatory scenarios investigating the impact of different assumptions of eggshell thinning on skylark population size, density and distribution in 10 Danish landscapes, chosen to represent the range of typical Danish agricultural conditions. Landscape and timing of application of the pesticide were found to be the most critical factors to consider in the impact assessment. Consequently, a regulatory scenario of monoculture spring barley with an early spray treatment eliciting the eggshell thinning effect was applied using concentrations eliciting effects of zero to 100% in steps of 5%. Setting the SPGs requires balancing scientific, social and political realities. However, the provision of clear and detailed options such as those from comprehensive simulation results can inform the decision process by improving transparency and by putting the more abstract testing data into the context of real-world impacts. Copyright © 2017 Elsevier Inc. All rights reserved.

  9. Population-Level Herd Protection of Males From a Female Human Papillomavirus Vaccination Program: Evidence from Australian Serosurveillance.

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    Pillsbury, Alexis J; Quinn, Helen E; Evans, TaNisha D; McIntyre, Peter B; Brotherton, Julia M L

    2017-09-01

    Australia instituted funded female human papillomavirus (HPV) immunization in 2007, followed by a targeted male vaccination program in 2013. To date, Australia is one of only several countries with a funded male HPV immunization program. In 2012-2013, we conducted a survey of HPV seroprevalence in males to assess whether or not a herd impact of female vaccination could be observed. We conducted a cross-sectional study of de-identified residual diagnostic test serum samples from males aged 15-39 years from laboratories in 3 Australian states and calculated the proportion seropositive to HPV types 6, 11, 16, and 18. We compared type-specific results by age group against those from a baseline 2005 Australian HPV serosurvey. There were decreases in proportion seropositive for every HPV type across all age groups, many statistically significant. The largest decrease was observed for HPV-11, with decreases of 8- and 9-fold for ages 20-29 and 30-39 years, respectively. Despite substantial reductions in seroprevalence, at least 9% of males were seropositive for at least 1 of the 4 HPV types. This is the first serosurvey confirming broad population-level impact in males from female HPV vaccination. Our research may assist policy makers considering implementing HPV vaccination programs.

  10. Non-Vegetated Playa Morphodynamics Using Multi-Temporal Landsat Imagery in a Semi-Arid Endorheic Basin: Salar de Uyuni, Bolivia

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    Jiaguang Li

    2014-10-01

    Full Text Available Playas in endorheic basins are of environmental value and highly scientific because of their natural habitats of a wide variety of species and indicators for climatic changes and tectonic activities within continents. Remote sensing, due to its capability of acquiring repetitive data with synoptic coverage, provides a unique tool to monitor and collect spatial information about playas. Most studies have concentrated on evaporite mineral distribution using remote sensing techniques but research about grain size distribution and geomorphologic changes in playas has been rarely reported. We analysed playa morphodynamics using Landsat time series data in a semi-arid endorheic basin, Salar de Uyuni in Bolivia. The spectral libraries explaining the relationship between surface reflectance and surficial materials are extracted from the Landsat image on 11 November 2012, the collected samples in the area and the precipitation data. Such spectral libraries are then applied to the classification of the other Landsat images from 1985–2011 using maximum likelihood classifier. Four types of surficial materials on the playa are identified: salty surface, silt-rich surface, clay-rich surface and pure salt. The silt-rich surface is related to crevasse splays and river banks while the clay-rich surface is associated with floodplain and channel depressions. The classification results show that the silt-rich surface tends to have a positive relationship with annual precipitation, whereas the salty surface negatively correlates with annual precipitation and there is no correlation between clay-rich surface and annual precipitation. Salty surfaces seem to consist primarily of clay due to their similar characteristics in response to precipitation changes. The classification results also show the development of a crevasse splay and avulsions. The results demonstrate the potential of Landsat imagery to determine the grain size and sedimentary facies distribution on

  11. Characterization of natural variation in North American Atlantic Salmon populations (Salmonidae: Salmo salar) at a locus with a major effect on sea age.

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    Kusche, Henrik; Côté, Guillaume; Hernandez, Cécilia; Normandeau, Eric; Boivin-Delisle, Damien; Bernatchez, Louis

    2017-08-01

    Age at maturity is a key life-history trait of most organisms. In anadromous salmonid fishes such as Atlantic Salmon (Salmo salar), age at sexual maturity is associated with sea age, the number of years spent at sea before the spawning migration. For the first time, we investigated the presence of two nonsynonymous vgll3 polymorphisms in North American Atlantic Salmon populations that relate to sea age in European salmon and quantified the natural variation at these and two additional candidate SNPs from two other genes. A targeted resequencing assay was developed and 1,505 returning adult individuals of size-inferred sea age and sex from four populations were genotyped. Across three of four populations sampled in Québec, Canada, the late-maturing component (MSW) of the population of a given sex exhibited higher proportions of SNP genotypes 54Thr vgll3 and 323Lys vgll3 compared to early-maturing fish (1SW), for example, 85% versus 53% of females from Trinité River carried 323Lys vgll3 (nMSW = 205 vs. n1SW = 30; p sea age was more pronounced in females than in males in the rivers we studied. Logistic regression analysis of vgll3 SNP genotypes revealed increased probabilities of exhibiting higher sea age for 54Thr vgll3 and 323Lys vgll3 genotypes compared to alternative genotypes, depending on population and sex. Moreover, individuals carrying the heterozygous vgll3 SNP genotypes were more likely (>66%) to be female. In summary, two nonsynonymous vgll3 polymorphisms were confirmed in North American populations of Atlantic Salmon and our results suggest that variation at those loci correlates with sea age and sex. Our results also suggest that this correlation varies among populations. Future work would benefit from a more balanced sampling and from adding data on juvenile riverine life stages to contrast our data.

  12. Dietary soya saponins increase gut permeability and play a key role in the onset of soyabean-induced enteritis in Atlantic salmon ( Salmo salar L.).

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    Knudsen, David; Jutfelt, Fredrik; Sundh, Henrik; Sundell, Kristina; Koppe, Wolfgang; Frøkiaer, Hanne

    2008-07-01

    Saponins are naturally occurring amphiphilic molecules and have been associated with many biological activities. The aim of the present study was to investigate whether soya saponins trigger the onset of soyabean-induced enteritis in Atlantic salmon (Salmo salar L.), and to examine if dietary soya saponins increase the epithelial permeability of the distal intestine in Atlantic salmon. Seven experimental diets containing different levels of soya saponins were fed to seawater-adapted Atlantic salmon for 53 d. The diets included a fishmeal-based control diet, two fishmeal-based diets with different levels of added soya saponins, one diet containing 25% lupin kernel meal, two diets based on 25% lupin kernel meal with different levels of added soya saponins, and one diet containing 25% defatted soyabean meal. The effect on intestinal morphology, intestinal epithelial permeability and faecal DM content was examined. Fish fed 25% defatted soyabean meal displayed severe enteritis, whereas fish fed 25% lupin kernel meal had normal intestinal morphology. The combination of soya saponins and fishmeal did not induce morphological changes but fish fed soya saponins in combination with lupin kernel meal displayed significant enteritis. Increased epithelial permeability was observed in fish fed 25% defatted soyabean meal and in fish fed soya saponin concentrate independent of the protein source in the feed. The study demonstrates that soya saponins, in combination with one or several unidentified components present in legumes, induce an inflammatory reaction in the distal intestine of Atlantic salmon. Soya saponins increase the intestinal epithelial permeability but do not, per se, induce enteritis.

  13. Volatile chemical spoilage indexes of raw Atlantic salmon (Salmo salar) stored under aerobic condition in relation to microbiological and sensory shelf lives.

    Science.gov (United States)

    Mikš-Krajnik, Marta; Yoon, Yong-Jin; Ukuku, Dike O; Yuk, Hyun-Gyun

    2016-02-01

    The purpose of this investigation was to identify and quantify the volatile chemical spoilage indexes (CSIs) for raw Atlantic salmon (Salmo salar) fillets stored under aerobic storage conditions at 4, 10 and 21 °C in relation to microbial and sensory shelf lives. The volatile organic compounds (VOCs) were analyzed with SPME-GC-MS technique. Through multivariate chemometric method, hierarchical cluster analysis (HCA) and Pearson's correlations, the CSIs: trimethylamine (TMA), ethanol (EtOH), 3-methyl-1-butanol (3Met-1But), acetoin and acetic acid (C2) were selected from the group of 28 detected VOCs. At the moment of microbiological shelf life established at total viable count (TVC) of 7.0 log CFU/g, the CSIs achieved levels of 11.5, 38.3, 0.3, 24.0 and 90.7 μg/g of salmon for TMA, EtOH, 3M-1But, acetoin and C2, respectively. Pseudomonas spp. was found as major specific spoilage organism (SSOs), suitable for shelf life prediction using modified Gompertz model at the cut-off level of 6.5 log CFU/g. H2S producing bacteria and Brochothrix thermosphacta were considered as important spoilage microorganisms; however, they were not suitable for shelf life estimation. Partial least square (PLS) regression revealed possible associations between microorganisms and synthetized VOCs, showing correlations between Pseudomonas spp. and 3Met-1But and aldehydes synthesis, lactic acid bacteria were linked with EtOH, C2 and esters, and B. thermosphacta with acetoin formation. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. Family-specific differences in growth rate and hepatic gene expression in juvenile triploid growth hormone (GH) transgenic Atlantic salmon (Salmo salar).

    Science.gov (United States)

    Xu, Qingheng; Feng, Charles Y; Hori, Tiago S; Plouffe, Debbie A; Buchanan, John T; Rise, Matthew L

    2013-12-01

    Growth hormone transgenic (GHTg) Atlantic salmon (Salmo salar) have enhanced growth when compared to their non-transgenic counterparts, and this trait can be beneficial for aquaculture production. Biological confinement of GHTg Atlantic salmon may be achieved through the induction of triploidy (3N). The growth rates of triploid GH transgenic (3NGHTg) Atlantic salmon juveniles were found to significantly vary between families in the AquaBounty breeding program. In order to characterize gene expression associated with enhanced growth in juvenile 3NGHTg Atlantic salmon, a functional genomics approach (32K cDNA microarray hybridizations followed by QPCR) was used to identify and validate liver transcripts that were differentially expressed between two fast-growing 3NGHTg Atlantic salmon families (AS11, AS26) and a slow-growing 3NGHTg Atlantic salmon family (AS25); juvenile growth rate was evaluated over a 45-day period. Of 687 microarray-identified differentially expressed features, 143 (116 more highly expressed in fast-growing and 27 more highly expressed in slow-growing juveniles) were identified in the AS11 vs. AS25 microarray study, while 544 (442 more highly expressed in fast-growing and 102 more highly expressed in slow-growing juveniles) were identified in the AS26 vs. AS25 microarray study. Forty microarray features (39 putatively associated with fast growth and 1 putatively associated with slow growth) were present in both microarray experiment gene lists. The expression levels of 15 microarray-identified transcripts were studied using QPCR with individual RNA samples to validate microarray results and to study biological variability of transcript expression. The QPCR results agreed with the microarray results for 12 of 13 putative fast-growth associated transcripts, but QPCR did not validate the microarray results for 2 putative slow-growth associated transcripts. Many of the 39 microarray-identified genes putatively associated at the transcript expression

  15. Move-by-move dynamics of the advantage in chess matches reveals population-level learning of the game.

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    Haroldo V Ribeiro

    Full Text Available The complexity of chess matches has attracted broad interest since its invention. This complexity and the availability of large number of recorded matches make chess an ideal model systems for the study of population-level learning of a complex system. We systematically investigate the move-by-move dynamics of the white player's advantage from over seventy thousand high level chess matches spanning over 150 years. We find that the average advantage of the white player is positive and that it has been increasing over time. Currently, the average advantage of the white player is 0.17 pawns but it is exponentially approaching a value of 0.23 pawns with a characteristic time scale of 67 years. We also study the diffusion of the move dependence of the white player's advantage and find that it is non-Gaussian, has long-ranged anti-correlations and that after an initial period with no diffusion it becomes super-diffusive. We find that the duration of the non-diffusive period, corresponding to the opening stage of a match, is increasing in length and exponentially approaching a value of 15.6 moves with a characteristic time scale of 130 years. We interpret these two trends as a resulting from learning of the features of the game. Additionally, we find that the exponent [Formula: see text] characterizing the super-diffusive regime is increasing toward a value of 1.9, close to the ballistic regime. We suggest that this trend is due to the increased broadening of the range of abilities of chess players participating in major tournaments.

  16. Tapetes microbianos del Salar de Llamará, norte de Chile Microbial mats from the Llamará salt flat, northern Chile

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    CECILIA DEMERGASSO

    2003-09-01

    incluyendo cocos y bacilos no identificados. En todos los tapetes muestreados en el Salar se encontraron bacterias reductoras de sulfato.Stratified photosynthetic microbial mats are described from the Salar de Llamará, a salt flat basin located in the Atacama desert of northern Chile. Microscopic and spectrophotometric techniques were used. The thickness of the photic zone of these communities spans 8 to 30 mm. This is probably due to the grain size and mineralogical composition of associated sediments. Three different types of mats were recognized. A first one was characterized by a green pigmented layer; a second with orange and green coloured layers, and the third with orange and green layers and an additional purple layer. At one sampling site, no pigmented layers were present. Sediments underlying the mats were white, but in one site, black coloured sediments were observed; this dark colour is probably the result of iron sulphide precipitation. Predominant microorganisms in the orange pigmented layers were diatoms and unicellular cyanobacteria, mainly from the Cyanothece and Synechococcus groups. Filamentous cyanobacteria Microleus sp. and Oscillatoria sp. were the most abundant in the green layer. When interstitial brines reached salinities between 12 and 33 %, no diatoms were observed, and the coccoidal cyanobacteria from the Synechococcus, Cyanothece and Gloeocapsa groups and genus Gloeobacter predominated over filamentous Cyanobacteria in the green layer. The purple layer was built primarily of anoxygenic phototrophic bacteria similar to cells of the genera Chromatium and Thiocapsa. Absorption spectra revealed that chlorophyll a is the most abundant pigment in most of analyzed samples. Integrated values of chlorophyll a and bacteriochlorophyll a reached values of up to 230 and 144 mg m-2 along all of the pigmented zone, respectively. Abundant non-photosynthetic microorganisms were found in the mats, including unidentified cocci and bacilli. Sulphate reducing

  17. Beyond the Normalized Difference Vegetation Index (NDVI): Developing a Natural Space Index for population-level health research.

    Science.gov (United States)

    Rugel, Emily J; Henderson, Sarah B; Carpiano, Richard M; Brauer, Michael

    2017-11-01

    Natural spaces can provide psychological benefits to individuals, but population-level epidemiologic studies have produced conflicting results. Refining current exposure-assessment methods is necessary to advance our understanding of population health and to guide the design of health-promoting urban forms. The aim of this study was to develop a comprehensive Natural Space Index that robustly models potential exposure based on the presence, form, accessibility, and quality of multiple forms of greenspace (e.g., parks and street trees) and bluespace (e.g., oceans and lakes). The index was developed for greater Vancouver, Canada. Greenness presence was derived from remote sensing (NDVI/EVI); forms were extracted from municipal and private databases; and accessibility was based on restrictions such as private ownership. Quality appraisals were conducted for 200 randomly sampled parks using the Public Open Space Desktop Appraisal Tool (POSDAT). Integrating these measures in GIS, exposure was assessed for 60,242 postal codes using 100- to 1,600-m buffers based on hypothesized pathways to mental health. A single index was then derived using principal component analysis (PCA). Comparing NDVI with alternate approaches for assessing natural space resulted in widely divergent results, with quintile rankings shifting for 22-88% of postal codes, depending on the measure. Overall park quality was fairly low (mean of 15 on a scale of 0-45), with no significant difference seen by neighborhood-level household income. The final PCA identified three main sets of variables, with the first two components explaining 68% of the total variance. The first component was dominated by the percentages of public and private greenspace and bluespace and public greenspace within 250m, while the second component was driven by lack of access to bluespace within 1 km. Many current approaches to modeling natural space may misclassify exposures and have limited specificity. The Natural Space Index

  18. MDR-TB treatment as prevention: The projected population-level impact of expanded treatment for multidrug-resistant tuberculosis.

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    Kendall, Emily A; Azman, Andrew S; Cobelens, Frank G; Dowdy, David W

    2017-01-01

    the population level. Focusing MDR diagnostic efforts on previously-treated cases is an efficient first-step approach.

  19. A highly redundant BAC library of Atlantic salmon (Salmo salar: an important tool for salmon projects

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    Koop Ben F

    2005-04-01

    Full Text Available Abstract Background As farming of Atlantic salmon is growing as an aquaculture enterprise, the need to identify the genomic mechanisms for specific traits is becoming more important in breeding and management of the animal. Traits of importance might be related to growth, disease resistance, food conversion efficiency, color or taste. To identify genomic regions responsible for specific traits, genomic large insert libraries have previously proven to be of crucial importance. These large insert libraries can be screened using gene or genetic markers in order to identify and map regions of interest. Furthermore, large-scale mapping can utilize highly redundant libraries in genome projects, and hence provide valuable data on the genome structure. Results Here we report the construction and characterization of a highly redundant bacterial artificial chromosome (BAC library constructed from a Norwegian aquaculture strain male of Atlantic salmon (Salmo salar. The library consists of a total number of 305 557 clones, in which approximately 299 000 are recombinants. The average insert size of the library is 188 kbp, representing 18-fold genome coverage. High-density filters each consisting of 18 432 clones spotted in duplicates have been produced for hybridization screening, and are publicly available 1. To characterize the library, 15 expressed sequence tags (ESTs derived overgos and 12 oligo sequences derived from microsatellite markers were used in hybridization screening of the complete BAC library. Secondary hybridizations with individual probes were performed for the clones detected. The BACs positive for the EST probes were fingerprinted and mapped into contigs, yielding an average of 3 contigs for each probe. Clones identified using genomic probes were PCR verified using microsatellite specific primers. Conclusion Identification of genes and genomic regions of interest is greatly aided by the availability of the CHORI-214 Atlantic salmon BAC

  20. Impact of Salmonid alphavirus infection in diploid and triploid Atlantic salmon (Salmo salar L. fry.

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    Tharangani K Herath

    Full Text Available With increasing interest in the use of triploid salmon in commercial aquaculture, gaining an understanding of how economically important pathogens affect triploid stocks is important. To compare the susceptibility of diploid and triploid Atlantic salmon (Salmo salar L. to viral pathogens, fry were experimentally infected with Salmonid alphavirus sub-type 1 (SAV1, the aetiological agent of pancreas disease (PD affecting Atlantic salmon aquaculture in Europe. Three groups of fry were exposed to the virus via different routes of infection: intraperitoneal injection (IP, bath immersion, or cohabitation (co-hab and untreated fry were used as a control group. Mortalities commenced in the co-hab challenged diploid and triploid fish from 11 days post infection (dpi, and the experiment was terminated at 17 dpi. Both diploid and triploid IP challenged groups had similar levels of cumulative mortality at the end of the experimental period (41.1% and 38.9% respectively, and these were significantly higher (p < 0.01 than for the other challenge routes. A TaqMan-based quantitative PCR was used to assess SAV load in the heart, a main target organ of the virus, and also liver, which does not normally display any pathological changes during clinical infections, but exhibited severe degenerative lesions in the present study. The median viral RNA copy number was higher in diploid fish compared to triploid fish in both the heart and the liver of all three challenged groups. However, a significant statistical difference (p < 0.05 was only apparent in the liver of the co-hab groups. Diploid fry also displayed significantly higher levels of pancreatic and myocardial degeneration than triploids. This study showed that both diploid and triploid fry are susceptible to experimental SAV1 infection. The lower virus load seen in the triploids compared to the diploids may possibly be related to differences in cell metabolism between the two groups, however, further

  1. Benzodiazepine Use, Misuse, and Harm at the Population Level in Canada: A Comprehensive Narrative Review of Data and Developments Since 1995.

    Science.gov (United States)

    Murphy, Yoko; Wilson, Emily; Goldner, Elliot M; Fischer, Benedikt

    2016-07-01

    Benzodiazepines are commonly prescribed psycho-pharmaceuticals (e.g., for anxiety, tension, and insomnia); they are generally considered safe but have potential adverse effects. Benzodiazepine use in Canada versus internationally is comparably high, yet no recent comprehensive review of use, misuse, or related (e.g., morbidity, mortality) harm at the population level exists; the present review aimed to fill this gap. We searched four key scientific literature databases (Medline, CINAHL, EBM Reviews, and Web of Science) with relevant search terms, and collected relevant "gray literature" (e.g., survey, monitoring, government reports) data published in 1995-2015. Two reviewers conducted data screening and extraction; results were categorized and narratively summarized by key sub-topics. Levels of benzodiazepine use in the general population have been relatively stable in recent years; medical use is generally highest among older adults. Rates of non-medical use are fairly low in general but higher in marginalized (e.g., street drug use) populations; high and/or inappropriate prescribing appears common in older adults. Benzodiazepines are associated with various morbidity outcomes (e.g., accidents/injuries, cognitive decline, sleep disturbances, or psychiatric issues), again commonly observed in older adults; moreover, benzodiazepines are identified as a contributing factor in suicides and poisoning deaths. Overall there is a substantial benzodiazepine-related health problem burden-although lower than that for other psycho-medications (e.g., opioids)-in Canada, mainly as a result of overuse and/or morbidity. National benzodiazepine prescription guidelines are lacking, and few evaluated interventions to reduce benzodiazepine-related problems exist. There is a clear need for reducing inappropriate benzodiazepine use and related harm in Canada through improved evidence-based practice as well as monitoring and control.

  2. Population-level Consequences of Breeding Phenology in Response to Climate Variability in Seabirds and Landbirds: Two Long-term Studies From California

    Science.gov (United States)

    Warzybok, P.; Nur, N.; Bradley, R.; Sydeman, W. J.; Abraham, C.; Chase, M. K.

    2007-12-01

    Long-term studies conducted on breeding populations on the Farallon Islands (1971 to 2007) and in the Point Reyes National Seashore (1980 to 2007), provide the means to characterize breeding phenology of seabird and landbird species and determine how that has changed over multiple temporal scales (variation among years, among decades, shifts in ocean regimes, etc.). However, to interpret phenological patterns and shifts requires information on the demography and ecological context of these species. Here we describe studies on three seabird species (Common Murre Uria aalge, Cassin's Auklet Ptychoramphus aleuticus, Brandt's Cormorant, Phalacrocorax penicillatus) where we have tied changes in breeding phenology, within a year, and among years, to demographic consequences (reproductive success, proportion of the population that breeds, adult survival, etc.). In addition, for these species we have information on diet choice of parents feeding chicks and how that has varied within and among years, as well as oceanographic correlates (sea surface temperature, upwelling indices, etc). Results reveal marked variation among the species in their response to oceanographic and climate variability, reflecting their different ecologies. We describe how these results can be used to forecast response to future climate change, as well as to interpret year by response to climate variability. We also summarize results from a long-term study of Song Sparrows (Melospiza melodia), where we have investigated onset and termination of breeding and the climate factors that may influence it, while identifying the population-level responses associated with phenological shifts. We close by making recommendations for large-scale monitoring of phenology based on these more localized studies.

  3. Analytic Review of Modeling Studies of ARV Based PrEP Interventions Reveals Strong Influence of Drug-Resistance Assumptions on the Population-Level Effectiveness

    Science.gov (United States)

    Dimitrov, Dobromir; Boily, Marie-Claude; Brown, Elizabeth R.; Hallett, Timothy B.

    2013-01-01

    Background Four clinical trials have shown that oral and topical pre-exposure prophylaxis (PrEP) based on tenofovir may be effective in preventing HIV transmission. The expected reduction in HIV transmission and the projected prevalence of drug resistance due to PrEP use vary significantly across modeling studies as a result of the broad spectrum of assumptions employed. Our goal is to quantify the influence of drug resistance assumptions on the predicted population-level impact of PrEP. Methods All modeling studies which evaluate the impact of oral or topical PrEP are reviewed and key assumptions regarding mechanisms of generation and spread of drug-resistant HIV are identified. A dynamic model of the HIV epidemic is developed to assess and compare the impact of oral PrEP using resistance assumptions extracted from published studies. The benefits and risks associated with ten years of PrEP use are evaluated under identical epidemic, behavioral and intervention conditions in terms of cumulative fractions of new HIV infections prevented, resistance prevalence among those infected with HIV, and fractions of infections in which resistance is transmitted. Results Published models demonstrate enormous variability in resistance-generating assumptions and uncertainty in parameter values. Depending on which resistance parameterization is used, a resistance prevalence between 2% and 44% may be expected if 50% efficacious oral PrEP is used consistently by 50% of the population over ten years. We estimated that resistance may be responsible for up to a 10% reduction or up to a 30% contribution to the fraction of prevented infections predicted in different studies. Conclusions Resistance assumptions used in published studies have a strong influence on the projected impact of PrEP. Modelers and virologists should collaborate toward clarifying the set of resistance assumptions biologically relevant to the PrEP products which are already in use or soon to be added to the arsenal

  4. Impacts of episodic acidification on in-stream survival and physiological impairment of Atlantic salmon (Salmo salar) smolts

    Science.gov (United States)

    McCormick, S.D.; Keyes, A.; Nislow, K.H.; Monette, M.Y.

    2009-01-01

    We conducted field studies to determine the levels of acid and aluminum (Al) that affect survival, smolt development, ion homeostasis, and stress in Atlantic salmon (Salmo salar) smolts in restoration streams of the Connecticut River in southern Vermont, USA. Fish were held in cages in five streams encompassing a wide range of acid and Al levels for two 6-day intervals during the peak of smolt development in late April and early May. Physiological parameters were unchanged from initial sampling at the hatchery and the high water quality reference site (pH > 7.0, inorganic Al water chemistry alone. The results indicate that Al and low pH under field conditions in some New England streams can cause mortality and impair smolt development in juvenile Atlantic salmon and provide direct evidence that episodic acidification is impacting conservation and recovery of Atlantic salmon in the northeastern USA.

  5. Biological variation of lipid constituents and distribution of tocopherols and astaxanthin in farmed Atlantic salmon (Salmo salar)

    DEFF Research Database (Denmark)

    Refsgaard, Hanne; Brockhoff, Per B; Jensen, Benny

    1998-01-01

    The contents of fat, astaxanthin, and tocogherols and the fatty acid composition of a homogeneous group of 145 farmed Atlantic salmon (Salmo salar) were determined. The analytical variation of the data was stastistically-separated from the biological variation. The fat content in the muscle near....... The concentrations of alpha-, gamma-, and delta-tocopherols were approximately 32, 2.9, and 0.4 mg/kg of muscle, respectively, and the biological standard deviations were 4.5, 0.4, and 0.07 mg/kg (14, 14, and 20%), respectively. in another group of five salmon the distributions throughout the fillet were determined......, longitudinally as well as transversally. The distribution of fat, astaxanthin, and tocopherols varied throughout the salmon. The fatty acid composition varied little between extracts from different locations of the fillet...

  6. Characterization of Mycobacterium salmoniphilum as causal agent of mycobacteriosis in Atlantic salmon, Salmo salar L., from a freshwater recirculation system.

    Science.gov (United States)

    Aro, L; Correa, K; Martínez, A; Ildefonso, R; Yáñez, J M

    2014-04-01

    Thirty Atlantic salmon, Salmo salar L., with low corporal condition relative to other fish present in the culture system, were sampled from a freshwater recirculation pisciculture located in Chile. The most characteristic signs and lesions were cachexia and presence of multiple greyish-white granulomas within internal organs. The external and internal lesions, along with the microscopic, histologic and biochemical findings, were consistent with mycobacteriosis. The identification of Mycobacterium salmoniphilum as the causal agent of the lesions was possible through the use of molecular analyses. This study represents the first report of Mycobacterium salmoniphilum in a freshwater recirculation system and the first case of fish mycobacteriosis described in Chile. © 2013 John Wiley & Sons Ltd.

  7. Evaluation of the rivers Vilnia and Siesartis ecotoxicological state based on morphological indexes of juvenile Atlantic salmon (Salmo salar L.

    Directory of Open Access Journals (Sweden)

    Gintarė Sauliutė

    2015-10-01

    Full Text Available Objective of the study – to evaluate ecotoxicological state of two probably differently polluted salmon rivers: the Vilnia and Siesartis based on Atlantic salmon (Salmo salar L. juvenile’s morphological indexes. Statistical analysis of estimated fish morphometric parameters and morphological indexes showed that the Vilnia and Siesartis Rivers’ salmon juveniles differ significantly. Condition factor (CF and the gills-somatic index (GSI were found to be the most sensitive biomarkers reflecting the physiological state of the fish. The Vilnia River salmon juvenile CF and GSI value was significantly different as compared with the Siesartis River’s salmon juvenile indexes, apparently, due to the increased water pollution. Since according to the classical physico-chemical parameters, both rivers’ water was very similar [no significant differences were found (p > 0.1], it was suggested that here exist other non-specific chemical factors (pollutants in water, which determine fish physiological and indicate river ecotoxicological states.

  8. Effects of TLR agonists and viral infection on cytokine and TLR expression in Atlantic salmon (Salmo salar).

    Science.gov (United States)

    Arnemo, Marianne; Kavaliauskis, Arturas; Gjøen, Tor

    2014-10-01

    The development of efficient and cheap vaccines against several aquatic viruses is necessary for a sustainable fish farming industry. Toll-like receptor (TLR) ligands have already been used as good adjuvants in human vaccines. With more understanding of TLR expression, function, and ligand specificity in fish, more efficient adjuvants for fish viral vaccines can be developed. In this paper, we examine all known TLRs in Atlantic salmon (Salmo salar) and demonstrate that head kidney and spleen are the main organs expressing TLRs in salmon. We also show that adherent head kidney leucocytes from salmon are able to respond to many of the known agonists for human TLRs, and that viral infection can induce up-regulation of several TLRs. These findings substantiate these receptors' role in immune responses to pathogens in salmonids making their ligands attractive as vaccine adjuvant candidates. Copyright © 2014 Elsevier Ltd. All rights reserved.

  9. Migratory behaviour and survival rates of wild northern Atlantic salmon Salmo salar post-smolts: Effects of environmental factors

    Science.gov (United States)

    Davidsen, J.G.; Rikardsen, A.H.; Halttunen, E.; Thorstad, E.B.; Okland, F.; Letcher, B.H.; Skarhamar, J.; Naesje, T.F.

    2009-01-01

    To study smolt behaviour and survival of a northern Atlantic salmon Salmo salar population during river descent, sea entry and fjord migration, 120 wild S. salar were tagged with acoustic tags and registered at four automatic listening station arrays in the mouth of the north Norwegian River Alta and throughout the Alta Fjord. An estimated 75% of the post-smolts survived from the river mouth, through the estuary and the first 17 km of the fjord. Survival rates in the fjord varied with fork length (LF), and ranged from 97??0 to 99??5% km-1. On average, the post-smolts spent 1??5 days (36 h, range 11-365 h) travelling from the river mouth to the last fjord array, 31 km from the river mouth. The migratory speed was slower (1??8 LF s-1) in the first 4 km after sea entry compared with the next 27 km (3??0 LF s-1). Post-smolts entered the fjord more often during the high or ebbing tide (70%). There was no clear diurnal migration pattern within the river and fjord, but most of the post-smolts entered the fjord at night (66%, 2000-0800 hours), despite the 24 h daylight at this latitude. The tidal cycle, wind-induced currents and the smolts' own movements seemed to influence migratory speeds and routes in different parts of the fjord. A large variation in migration patterns, both in the river and fjord, might indicate that individuals in stochastic estuarine and marine environments are exposed to highly variable selection regimes, resulting in different responses to environmental factors on both temporal and spatial scales. Post-smolts in the northern Alta Fjord had similar early marine survival rates to those observed previously in southern fjords; however, fjord residency in the north was shorter. ?? 2009 The Fisheries Society of the British Isles.

  10. Physiological preparedness and performance of Atlantic salmon Salmo salar smolts in relation to behavioural salinity preferences and thresholds.

    Science.gov (United States)

    Stich, D S; Zydlewski, G B; Zydlewski, J D

    2016-02-01

    This study investigated the relationships between behavioural responses of Atlantic salmon Salmo salar smolts to saltwater (SW) exposure and physiological characteristics of smolts in laboratory experiments. It concurrently described the behaviour of acoustically tagged smolts with respect to SW and tidal cycles during estuary migration. Salmo salar smolts increased their use of SW relative to fresh water (FW) from April to June in laboratory experiments. Mean preference for SW never exceeded 50% of time in any group. Preference for SW increased throughout the course of smolt development. Maximum continuous time spent in SW was positively related to gill Na(+), K(+)-ATPase (NKA) activity and osmoregulatory performance in full-strength SW (measured as change in gill NKA activity and plasma osmolality). Smolts decreased depth upon reaching areas of the Penobscot Estuary where SW was present, and all fish became more surface oriented during passage from head of tide to the ocean. Acoustically tagged, migrating smolts with low gill NKA activity moved faster in FW reaches of the estuary than those with higher gill NKA activity. There was no difference in movement rate through SW reaches of the estuary based on gill NKA activity. Migrating fish moved with tidal flow during the passage of the lower estuary based on the observed patterns in both vertical and horizontal movements. The results indicate that smolts select low-salinity water during estuary migration and use tidal currents to minimize energetic investment in seaward migration. Seasonal changes in osmoregulatory ability highlight the importance of the timing of stocking and estuary arrival. © 2015 The Fisheries Society of the British Isles.

  11. Gill damage to Atlantic salmon (Salmo salar) caused by the common jellyfish (Aurelia aurita) under experimental challenge.

    Science.gov (United States)

    Baxter, Emily J; Sturt, Michael M; Ruane, Neil M; Doyle, Thomas K; McAllen, Rob; Harman, Luke; Rodger, Hamish D

    2011-04-07

    Over recent decades jellyfish have caused fish kill events and recurrent gill problems in marine-farmed salmonids. Common jellyfish (Aurelia spp.) are among the most cosmopolitan jellyfish species in the oceans, with populations increasing in many coastal areas. The negative interaction between jellyfish and fish in aquaculture remains a poorly studied area of science. Thus, a recent fish mortality event in Ireland, involving Aurelia aurita, spurred an investigation into the effects of this jellyfish on marine-farmed salmon. To address the in vivo impact of the common jellyfish (A. aurita) on salmonids, we exposed Atlantic salmon (Salmo salar) smolts to macerated A. aurita for 10 hrs under experimental challenge. Gill tissues of control and experimental treatment groups were scored with a system that rated the damage between 0 and 21 using a range of primary and secondary parameters. Our results revealed that A. aurita rapidly and extensively damaged the gills of S. salar, with the pathogenesis of the disorder progressing even after the jellyfish were removed. After only 2 hrs of exposure, significant multi-focal damage to gill tissues was apparent. The nature and extent of the damage increased up to 48 hrs from the start of the challenge. Although the gills remained extensively damaged at 3 wks from the start of the challenge trial, shortening of the gill lamellae and organisation of the cells indicated an attempt to repair the damage suffered. Our findings clearly demonstrate that A. aurita can cause severe gill problems in marine-farmed fish. With aquaculture predicted to expand worldwide and evidence suggesting that jellyfish populations are increasing in some areas, this threat to aquaculture is of rising concern as significant losses due to jellyfish could be expected to increase in the future.

  12. Distribution by origin and sea age of Atlantic salmon (Salmo salar) in the sea around the Faroe Islands based on analysis of historical tag recoveries

    DEFF Research Database (Denmark)

    Jacobsen, Jan Arge; Hansen, Lars P.; Bakkestuen, Vegar

    2012-01-01

    Distribution by origin and sea age of Atlantic salmon (Salmo salar) in the sea around the Faroe Islands based on analysis of historical tag recoveries. – ICES Journal of Marine Science, 69: 1598–1608.A database of 2651 tags applied to Atlantic salmon (Salmo salar) smolts in 13 countries...... countries in the southern European stock complex. Furthermore, the proportion of tag recoveries from southern European countries was higher in autumn, and the proportion recovered from northern European countries higher in winter. The apparent temporal and spatial segregation of stocks of different origin...... suggests that there may have been differential exploitation on these stocks, which provides information that could inform fishery management with regard to temporal and/or spatial fishery options for the Faroes commercial salmon fishery should it recommence in future...

  13. Comparison of laboratory single species and field population-level effects of the pyrethroid insecticide lambda-cyhalothrin on freshwater invertebrates

    NARCIS (Netherlands)

    Schroer, A.F.W.; Belgers, J.D.M.; Brock, T.C.M.; Matser, A.M.; Maund, S.J.; Brink, van den P.J.

    2004-01-01

    The toxicity of the pyrethroid insecticide lambda-cyhalothrin to freshwater invertebrates has been investigated using data from short-term laboratory toxicity tests and in situ bioassays and population-level effects in field microcosms. In laboratory tests, patterns of toxicity were consistent with

  14. Variation in population levels of physical activity in European adults according to cross-European studies: a systematic literature review within DEDIPAC

    NARCIS (Netherlands)

    Loyen, A.; Hecke, L. van; Verloigne, M.; Hendriksen, I.; Lakerveld, J.; Steene-Johannessen, J.; Vuillemin, A.; Koster, A.; Donnelly, A.; Ekelund, U.; Deforche, B.; Bourdeaudhuij, I. de; Brug, J.; Ploeg, H.P. van der

    2016-01-01

    Background: Physical inactivity is a well-known public health risk that should be monitored at the population level. Physical activity levels are often surveyed across Europe. This systematic literature review aims to provide an overview of all existing cross-European studies that assess physical

  15. Variation in population levels of physical activity in European adults according to cross-European studies: a systematic literature review within DEDIPAC

    NARCIS (Netherlands)

    Loyen, A.; Van Hecke, L.; Verloigne, M.; Hendriksen, I.; Lakerveld, J.; Steene-Johannessen, J.; Vuillemin, A.; Koster, A.; Donnelly, A.; Ekelund, U.; Deforche, B.; De Bourdeaudhuij, I.; Brug, J.; van der Ploeg, H.P.

    2016-01-01

    Background Physical inactivity is a well-known public health risk that should be monitored at the population level. Physical activity levels are often surveyed across Europe. This systematic literature review aims to provide an overview of all existing cross-European studies that assess physical

  16. Socio-behavioural aspects in the prevention and control of dental caries and periodontal diseases at an individual and population level

    NARCIS (Netherlands)

    Sälzer, S.; Alkilzy, M.; Slot, D.E.; Dörfer, C.E.; Schmoeckel, J.; Splieth, C.H.

    AIM: Aim was to systematically review behavioural aspects in the prevention and control of dental caries and periodontal diseases at individual and population level. MATERIAL & METHODS: With regard to caries, MEDLINE/PubMed was searched on three subheadings focusing on early childhood, proximal and

  17. Landlocked Atlantic salmon Salmo salar L. and trout Salmo trutta L. in the regulated River Klarälven, Sweden : Implications for conservation and management

    OpenAIRE

    Norrgård, Johnny R

    2011-01-01

    Conservation and management of migratory salmonids requires an understanding of their ecology at multiple scales, and a holistic view, including assessment of historical and present anthropogenic impacts. In the regulated River Klarälven, with 11 hydropower dams, populations of landlocked Atlantic salmon Salmo salar and migratory brown trout Salmo trutta have declined due to human activities. Maintaining viable populations of salmon in the River Klarälven has high priority, given there are fe...

  18. Testing three common stocking methods: Differences in smolt size, migration rate and timing of two strains of stocked Atlantic salmon ( Salmo salar )

    DEFF Research Database (Denmark)

    Birnie-Gauvin, Kim; Larsen, Martin Hage; Thomassen, Søren T.

    2018-01-01

    The influence of three common stocking practices for two strains (Ätran and Burrishoole) of hatchery-reared Atlantic salmon, Salmo salar, on smolt size, migration probability and migration timing were investigated in situ. Using a common garden experiment, fish from these populations were released...... to inherited factors, and emphasize the importance of considering age of fish and time spent in the hatchery when stocking populations in the wild to maximize smolt output...

  19. Assessing groundwater recharge in an Andean closed basin using isotopic characterization and a rainfall-runoff model: Salar del Huasco basin, Chile

    Science.gov (United States)

    Uribe, Javier; Muñoz, José F.; Gironás, Jorge; Oyarzún, Ricardo; Aguirre, Evelyn; Aravena, Ramón

    2015-11-01

    Closed basins are catchments whose drainage networks converge to lakes, salt flats or alluvial plains. Salt flats in the closed basins in arid northern Chile are extremely important ecological niches. The Salar del Huasco, one of these salt flats located in the high plateau (Altiplano), is a Ramsar site located in a national park and is composed of a wetland ecosystem rich in biodiversity. The proper management of the groundwater, which is essential for the wetland function, requires accurate estimates of recharge in the Salar del Huasco basin. This study quantifies the spatio-temporal distribution of the recharge, through combined use of isotopic characterization of the different components of the water cycle and a rainfall-runoff model. The use of both methodologies aids the understanding of hydrological behavior of the basin and enabled estimation of a long-term average recharge of 22 mm/yr (i.e., 15 % of the annual rainfall). Recharge has a high spatial variability, controlled by the geological and hydrometeorological characteristics of the basin, and a high interannual variability, with values ranging from 18 to 26 mm/yr. The isotopic approach allowed not only the definition of the conceptual model used in the hydrological model, but also eliminated the possibility of a hydrogeological connection between the aquifer of the Salar del Huasco basin and the aquifer that feeds the springs of the nearby town of Pica. This potential connection has been an issue of great interest to agriculture and tourism activities in the region.

  20. HIV-1 transmission patterns in antiretroviral therapy-naive, HIV-infected North Americans based on phylogenetic analysis by population level and ultra-deep DNA sequencing.

    Directory of Open Access Journals (Sweden)

    Lisa L Ross

    Full Text Available Factors that contribute to the transmission of human immunodeficiency virus type 1 (HIV-1, especially drug-resistant HIV-1 variants remain a significant public health concern. In-depth phylogenetic analyses of viral sequences obtained in the screening phase from antiretroviral-naïve HIV-infected patients seeking enrollment in EPZ108859, a large open-label study in the USA, Canada and Puerto Rico (ClinicalTrials.gov NCT00440947 were examined for insights into the roles of drug resistance and epidemiological factors that could impact disease dissemination. Viral transmission clusters (VTCs were initially predicted from a phylogenetic analysis of population level HIV-1 pol sequences obtained from 690 antiretroviral-naïve subjects in 2007. Subsequently, the predicted VTCs were tested for robustness by ultra deep sequencing (UDS using pyrosequencing technology and further phylogenetic analyses. The demographic characteristics of clustered and non-clustered subjects were then compared. From 690 subjects, 69 were assigned to 1 of 30 VTCs, each containing 2 to 5 subjects. Race composition of VTCs were significantly more likely to be white (72% vs. 60%; p = 0.04. VTCs had fewer reverse transcriptase and major PI resistance mutations (9% vs. 24%; p = 0.002 than non-clustered sequences. Both men-who-have-sex-with-men (MSM (68% vs. 48%; p = 0.001 and Canadians (29% vs. 14%; p = 0.03 were significantly more frequent in VTCs than non-clustered sequences. Of the 515 subjects who initiated antiretroviral therapy, 33 experienced confirmed virologic failure through 144 weeks while only 3/33 were from VTCs. Fewer VTCs subjects (as compared to those with non-clustering virus had HIV-1 with resistance-associated mutations or experienced virologic failure during the course of the study. Our analysis shows specific geographical and drug resistance trends that correlate well with transmission clusters defined by HIV sequences of similarity

  1. Dose-dependent consumption of farmed Atlantic salmon (Salmo salar) increases plasma phospholipid n-3 fatty acids differentially.

    Science.gov (United States)

    Raatz, Susan K; Rosenberger, Thad A; Johnson, LuAnn K; Wolters, William W; Burr, Gary S; Picklo, Matthew J

    2013-02-01

    Enhanced n-3 fatty acid intake benefits cardiovascular disease (CVD) risk reduction. Increasing consumption at a population level may be better addressed by diet than through supplementation. However, limited data are available on the effect of the dose response to fish intake on plasma levels of n-3 fatty acids. To compare the effects of different doses of farmed Atlantic salmon on plasma phospholipid fatty acid proportions and CVD risk biomarkers (eg, glucose, insulin, homeostasis model of assessment-insulin resistance, high-sensitivity C-reactive protein, and interleukin-6) in healthy subjects we performed a randomized three-period crossover-designed trial (4-week treatment, 4- to 8-week washout) to compare the effects of twice per week consumption of farmed Atlantic salmon at doses of 90, 180, and 270 g in 19 apparently healthy men and women (mean age 40 to 65 years) and a body mass index between 25 and 34.9. All study visits were conducted at the US Department of Agriculture Agricultural Research Service Grand Forks Human Nutrition Research Center. Eicosapentaenoic acid and total n-3 concentrations were increased (Pfarmed Atlantic salmon to the diet twice per week for 4 weeks at portions of 180 g and 270 g modifies phospholipid fatty acid proportions of n-3 and n-6 in a level associated with decreased risk for CVD. Copyright © 2013 Academy of Nutrition and Dietetics. Published by Elsevier Inc. All rights reserved.

  2. Trophic calculations reveal the mechanism of population-level variation in mercury concentrations between marine ecosystems: case studies of two polar seabirds.

    Science.gov (United States)

    Brasso, Rebecka L; Polito, Michael J

    2013-10-15

    The incorporation of quantitative trophic level analysis in ecotoxicological studies provides explanatory power to identify the factors, trophic or environmental, driving population-level variation in mercury exposure at large geographic scales. In the Antarctic marine ecosystem, mercury concentrations and stable isotope values in Adélie penguins (Pygoscelis adeliae) were compared between the Antarctic Peninsula and the Ross Sea. Correcting tissue δ(15)N values for baseline δ(15)N values revealed population-level differences in trophic position which contributes to differences in mercury. Data from Thick-billed murres (Uria lomvia) were synthesized from published values from Baffin Bay and Svalbard to demonstrate the utility of baseline δ(15)N values in identifying differences in environmental mercury exposure independent of diet. Here, we demonstrate the importance of calculating population-specific trophic level data to uncover the source of variation in mercury concentrations between geographically distinct populations of marine predators. Copyright © 2013 Elsevier Ltd. All rights reserved.

  3. Monitoring Child Abuse and Neglect at a Population Level: Patterns of Hospital Admissions for Maltreatment and Assault

    Science.gov (United States)

    O'Donnell, Melissa; Nassar, Natasha; Leonard, Helen; Mathews, Richard; Patterson, Yvonne; Stanley, Fiona

    2010-01-01

    Objectives: To investigate the prevalence, trends, and characteristics of maltreatment and assault related hospital admissions and deaths among children; and identify common injuries and conditions associated with these admissions using routinely collected morbidity and mortality data. Methods: A retrospective cohort study of all children aged…

  4. Criterion 1: Conservation of biological diversity - Indicator 9: Population levels of representative species from diverse habitats monitored across their range

    Science.gov (United States)

    Carolyn Hull Sieg; Curtis H. Flather; Noah Barstatis

    2003-01-01

    This indicator estimates population trends of selected species as a surrogate measure of genetic diversity. Decreases in genetic diversity as populations decline, particularly if associated with small populations, contribute to increased risk of extinction. This indicator also provides an important measure of general biodiversity, as changes in species abundances are a...

  5. Employing individual measures of baseline glucocorticoids as population-level conservation biomarkers: considering within-individual variation in a breeding passerine.

    Science.gov (United States)

    Madliger, Christine L; Love, Oliver P

    2016-01-01

    Labile physiological variables, such as stress hormones [i.e. glucocorticoids (GCs)], allow individuals to react to perturbations in their environment and may therefore reflect the effect of disturbances or positive conservation initiatives in advance of population-level demographic measures. Although the application of GCs as conservation biomarkers has been of extensive interest, few studies have explicitly investigated whether baseline GC concentrations respond to disturbances consistently across individuals. However, confirmation of consistent responses is of paramount importance to assessing the ease of use of GCs in natural systems and to making valid interpretations regarding population-level change (or lack of change) in GC concentrations. We investigated whether free-ranging female tree swallows (Tachycineta bicolor) display individually specific changes in baseline glucocorticoid concentrations naturally over the breeding season (from incubation to offspring provisioning) and in response to a manipulation of foraging profitability (representing a decrease in access to food resources). We show that baseline GC concentrations are repeatable within individuals over reproduction in natural conditions. However, in response to a reduction in foraging ability, baseline GC concentrations increase at the population level but are not repeatable within individuals, indicating a high level of within-individual variation. Overall, we suggest that baseline GCs measured on a subset of individuals may not provide a representative indication of responses to environmental change at the population level, and multiple within-individual measures may be necessary to determine the fitness correlates of GC concentrations. Further validation should be completed across a variety of taxa and life-history stages. Moving beyond a traditional cross-sectional approach by incorporating repeated-measures methods will be necessary to assess the suitability of baseline GCs as biomarkers of

  6. Contrasting population-level responses to Pleistocene climatic oscillations in an alpine bat revealed by complete mitochondrial genomes and evolutionary history inference

    DEFF Research Database (Denmark)

    Alberdi, Antton; Gilbert, M. Thomas P; Razgour, Orly

    2015-01-01

    Aim: We used an integrative approach to reconstruct the evolutionary history of the alpine long-eared bat, Plecotus macrobullaris, to test whether the variable effects of Pleistocene climatic oscillations across geographical regions led to contrasting population-level demographic histories within...... a single species. Location: The Western Palaearctic. Methods: We sequenced the complete mitochondrial genomes of 57 individuals from across the distribution of the species. The analysis integrated ecological niche modelling (ENM), approximate Bayesian computation (ABC), measures of genetic diversity...

  7. Selective toxin effects on faster and slower growing individuals in the formation of hormesis at the population level - A case study with Lactuca sativa and PCIB.

    Science.gov (United States)

    Belz, Regina G; Sinkkonen, Aki

    2016-10-01

    Natural plant populations have large phenotypic plasticity that enhances acclimation to local stress factors such as toxin exposures. While consequences of high toxin exposures are well addressed, effects of low-dose toxin exposures on plant populations are seldom investigated. In particular, the importance of 'selective low-dose toxicity' and hormesis, i.e. stimulatory effects, has not been studied simultaneously. Since selective toxicity can change the size distribution of populations, we assumed that hormesis alters the size distribution at the population level, and investigated whether and how these two low-dose phenomena coexist. The study was conducted with Lactuca sativa L. exposed to the auxin-inhibitor 2-(p-chlorophenoxy)-2-methylpropionic acid (PCIB) in vitro. In two separate experiments, L. sativa was exposed to 12 PCIB doses in 24 replicates (50 plants/replicate). Shoot/root growth responses at the population level were compared to the fast-growing (≥90% percentile) and the slow-growing subpopulations (≤10% percentile) by Mann-Whitney U testing and dose-response modelling. In the formation of pronounced PCIB hormesis at the population level, low-dose effects proved selective, but widely stimulatory which seems to counteract low-dose selective toxicity. The selectivity of hormesis was dose- and growth rate-dependent. Stimulation occurred at lower concentrations and stimulation percentage was higher among slow-growing individuals, but partly or entirely masked at the population level by moderate or negligible stimulation among the faster growing individuals. We conclude that the hormetic effect up to the maximum stimulation may be primarily facilitated by an increase in size of the most slow-growing individuals, while thereafter it seems that mainly the fast-growing individuals contributed to the observed hormesis at the population level. As size distribution within a population is related to survival, our study hints that selective effects on slow

  8. Quantifying population-level risks using an individual-based model: sea otters, Harlequin Ducks, and the Exxon Valdez oil spill.

    Science.gov (United States)

    Harwell, Mark A; Gentile, John H; Parker, Keith R

    2012-07-01

    Ecological risk assessments need to advance beyond evaluating risks to individuals that are largely based on toxicity studies conducted on a few species under laboratory conditions, to assessing population-level risks to the environment, including considerations of variability and uncertainty. Two individual-based models (IBMs), recently developed to assess current risks to sea otters and seaducks in Prince William Sound more than 2 decades after the Exxon Valdez oil spill (EVOS), are used to explore population-level risks. In each case, the models had previously shown that there were essentially no remaining risks to individuals from polycyclic aromatic hydrocarbons (PAHs) derived from the EVOS. New sensitivity analyses are reported here in which hypothetical environmental exposures to PAHs were heuristically increased until assimilated doses reached toxicity reference values (TRVs) derived at the no-observed-adverse-effects and lowest-observed-adverse-effects levels (NOAEL and LOAEL, respectively). For the sea otters, this was accomplished by artificially increasing the number of sea otter pits that would intersect remaining patches of subsurface oil residues by orders of magnitude over actual estimated rates. Similarly, in the seaduck assessment, the PAH concentrations in the constituents of diet, sediments, and seawater were increased in proportion to their relative contributions to the assimilated doses by orders of magnitude over measured environmental concentrations, to reach the NOAEL and LOAEL thresholds. The stochastic IBMs simulated millions of individuals. From these outputs, frequency distributions were derived of assimilated doses for populations of 500,000 sea otters or seaducks in each of 7 or 8 classes, respectively. Doses to several selected quantiles were analyzed, ranging from the 1-in-1000th most-exposed individuals (99.9% quantile) to the median-exposed individuals (50% quantile). The resulting families of quantile curves provide the basis for

  9. Quantifying Population-Level Risks Using an Individual-Based Model: Sea Otters, Harlequin Ducks, and the Exxon Valdez Oil Spill

    Science.gov (United States)

    Harwell, Mark A; Gentile, John H; Parker, Keith R

    2012-01-01

    Ecological risk assessments need to advance beyond evaluating risks to individuals that are largely based on toxicity studies conducted on a few species under laboratory conditions, to assessing population-level risks to the environment, including considerations of variability and uncertainty. Two individual-based models (IBMs), recently developed to assess current risks to sea otters and seaducks in Prince William Sound more than 2 decades after the Exxon Valdez oil spill (EVOS), are used to explore population-level risks. In each case, the models had previously shown that there were essentially no remaining risks to individuals from polycyclic aromatic hydrocarbons (PAHs) derived from the EVOS. New sensitivity analyses are reported here in which hypothetical environmental exposures to PAHs were heuristically increased until assimilated doses reached toxicity reference values (TRVs) derived at the no-observed-adverse-effects and lowest-observed-adverse-effects levels (NOAEL and LOAEL, respectively). For the sea otters, this was accomplished by artificially increasing the number of sea otter pits that would intersect remaining patches of subsurface oil residues by orders of magnitude over actual estimated rates. Similarly, in the seaduck assessment, the PAH concentrations in the constituents of diet, sediments, and seawater were increased in proportion to their relative contributions to the assimilated doses by orders of magnitude over measured environmental concentrations, to reach the NOAEL and LOAEL thresholds. The stochastic IBMs simulated millions of individuals. From these outputs, frequency distributions were derived of assimilated doses for populations of 500 000 sea otters or seaducks in each of 7 or 8 classes, respectively. Doses to several selected quantiles were analyzed, ranging from the 1-in-1000th most-exposed individuals (99.9% quantile) to the median-exposed individuals (50% quantile). The resulting families of quantile curves provide the basis for

  10. Transcriptomic and physiological responses to fishmeal substitution with plant proteins in formulated feed in farmed Atlantic salmon (Salmo salar).

    Science.gov (United States)

    Tacchi, Luca; Secombes, Christopher J; Bickerdike, Ralph; Adler, Michael A; Venegas, Claudia; Takle, Harald; Martin, Samuel A M

    2012-08-01

    Aquaculture of piscivorous fish is in continual expansion resulting in a global requirement to reduce the dependence on wild caught fish for generation of fishmeal and fish oil. Plant proteins represent a suitable protein alternative to fish meal and are increasingly being used in fish feed. In this study, we examined the transcriptional response of Atlantic salmon (Salmo salar) to a high marine protein (MP) or low fishmeal, higher plant protein replacement diet (PP), formulated to the same nutritional specification within previously determined acceptable maximum levels of individual plant feed materials. After 77 days of feeding the fish in both groups doubled in weight, however neither growth performance, feed efficiency, condition factor nor organ indices were significantly different. Assessment of histopathological changes in the heart, intestine or liver did not reveal any negative effects of the PP diet. Transcriptomic analysis was performed in mid intestine, liver and skeletal muscle, using an Atlantic salmon oligonucleotide microarray (Salar_2, Agilent 4x44K). The dietary comparison revealed large alteration in gene expression in all the tissues studied between fish on the two diets. Gene ontology analysis showed, in the mid intestine of fish fed PP, higher expression of genes involved in enteritis, protein and energy metabolism, mitochondrial activity/kinases and transport, and a lower expression of genes involved in cell proliferation and apoptosis compared to fish fed MP. The liver of fish fed PP showed a lower expression of immune response genes but a higher expression of cell proliferation and apoptosis processes that may lead to cell reorganization in this tissue. The skeletal muscle of fish fed PP vs MP was characterized by a suppression of processes including immune response, energy and protein metabolism, cell proliferation and apoptosis which may reflect a more energy efficient tissue. The PP diet resulted in significant effects on transcription

  11. HIV-1 Adaptation to Antigen Processing Results in Population-Level Immune Evasion and Affects Subtype Diversification

    DEFF Research Database (Denmark)

    Tenzer, Stefan; Crawford, Hayley; Pymm, Phillip

    2014-01-01

    The recent HIV-1 vaccine failures highlight the need to better understand virus-host interactions. One key question is why CD8(+) T cell responses to two HIV-Gag regions are uniquely associated with delayed disease progression only in patients expressing a few rare HLA class I variants when these...... people vaccinated with natural HIV-1 sequence constructs. Our results suggest that artificial sequence modifications at subtype-specific positions in vitro could refocus and reverse the poor immunogenicity of HIV proteins.......The recent HIV-1 vaccine failures highlight the need to better understand virus-host interactions. One key question is why CD8(+) T cell responses to two HIV-Gag regions are uniquely associated with delayed disease progression only in patients expressing a few rare HLA class I variants when...... these regions encode epitopes presented by ~30 more common HLA variants. By combining epitope processing and computational analyses of the two HIV subtypes responsible for ~60% of worldwide infections, we identified a hitherto unrecognized adaptation to the antigen-processing machinery through substitutions...

  12. LOS CONFLICTOS ETNOAMBIENTALES DE "PAMPA COLORADA" Y "EL TATIO" EN EL SALAR DE ATACAMA, NORTE DE CHILE: PROCESOS ÉTNICOS EN UN CONTEXTO MINERO Y TURÍSTICO TRANSNACIONAL

    OpenAIRE

    Bolados García,Paola

    2014-01-01

    En el segundo lustro del 2000, las poblaciones indígenas del salar de Atacama (norte de Chile) fueron protagonistas de dos emblemáticos conflictos conocidos como "Pampa Colorada" y "la Defensa del Tatio".Analizamos en este artículo las relaciones entre los procesos étnicos de los años noventa experimentados en el salar y las economías transnacionales de enclave, como la minería y el turismo, que ingresaron en ese mismo período a esta región, producto de un cambio en el marco jurídico y legal ...

  13. Effect of intercropping of maize, bean, cabbage and toxicants on the population levels of some insect pests and associated predators in sugar beet plantations

    Directory of Open Access Journals (Sweden)

    S.K.M. El-Fakharany

    2012-01-01

    Full Text Available Experiments were carried out at El-Riad district, Kafr El-Sheikh Governorate in two successive growing seasons (2009/10 and 2010/11 to study the effect of intercropping of faba bean, maize and cabbage with sugar beet on the population density of Empoasca spp. (nymphs and adults, Aphis spp. (nymphs and adults, Bemisia tabaci (adults, Pegomyia mixta (eggs and larvae, Cassida vittata (larvae, pupae and adults and predators in sugar beet plantations compared with the non-intercropped plants and the resulting yield. The toxicity of certain compounds: fenitrothion, super misrona, sour orange oil, acidless orange oil, and Bermectine in reducing the population density of P. mixta and C. vittata larvae infesting sugar beet was evaluated. The rate of infestation was higher in the sole sugar beet plants than in those intercropped with faba bean, maize and cabbage plants which caused reduction of sucking pests and P. mixta eggs in the two seasons. The intercropping of faba bean plants led to higher infestation rate of P. mixta larvae in the two seasons and C. vittata (larvae, pupae and adults in the first season. The intercropping with maize led to a higher population density of Chrysoperla carnea, Paederus alfierii and Scymnus spp. in the two seasons. Low population density of true spiders was observed in sole sugar beet (control when compared with faba bean, maize and cabbage plants intercropped in the two seasons. Concerning the obtained root yield, the intercropping with maize and cabbage plants reduced the resultant yield of sugar beet roots in the two seasons. Bermectine and fenitrothion were the most effective toxicants followed by super misrona and then, sour orange that induced the lowest reduction in P. mixta larvae. Also, fenitrothion and Bermectine were the most potent compounds in reducing the population density of C. vittata larvae followed by super misrona and then, plant oil extracts. Concerning the side effects of these compounds on predators, sour orange oil and acidless orange oil had slight effects, whereas Bermectine and super misrona caused a moderate effect against predators. However, fenitrothion was the most highest toxic compound against predators.

  14. Self-reported oral health of a metropolitan homeless population in Australia: comparisons with population-level data.

    Science.gov (United States)

    Parker, E J; Jamieson, L M; Steffens, M A; Cathro, P; Logan, R M

    2011-09-01

    There is limited information on self-perceived oral health of homeless populations. This study quantified self-reported oral health among a metropolitan homeless adult population and compared against a representative sample of the metropolitan adult population obtained from the National Survey of Adult Oral Health. A total of 248 homeless participants (age range 17-78 years, 79% male) completed a self-report questionnaire. Data for an age-matched, representative sample of metropolitan-dwelling adults were obtained from Australia's second National Survey of Adult Oral Health. Percentage responses and 95% confidence intervals were calculated, with non-overlapping 95% confidence intervals used to identify statistically significant differences between the two groups. Homeless adults reported poorer oral health than their age-matched general population counterparts. Twice as many homeless adults reported visiting a dentist more than a year ago and that their usual reason for dental attendance was for a dental problem. The proportion of homeless adults with a perceived need for fillings or extractions was also twice that of their age-matched general population counterparts. Three times as many homeless adults rated their oral health as 'fair' or 'poor'. A significantly greater proportion of homeless adults in an Australian metropolitan location reported poorer oral health compared with the general metropolitan adult population. © 2011 Australian Dental Association.

  15. Community- and population-level changes in diatom size structure in a subarctic lake over the last two centuries

    Directory of Open Access Journals (Sweden)

    Elizabeth A. Kerrigan

    2015-07-01

    Full Text Available Climate change over the last two centuries has been associated with significant shifts in diatom community structure in lakes from the high arctic to temperate latitudes. To test the hypotheses that recent climate warming selects for species of smaller size within communities and a decrease in the average size of species within populations, we quantified the size of individual diatom valves from 10 depths in a sediment core covering the last ∼200 years from a pristine subarctic lake. Over the last ∼200 years, changes in the relative abundance of species of different average size and changes in the average valve size of populations of species contribute equally to the changes in community size structure, but are often opposite in sign, compensating for one another and moderating temporal changes in community size structure. In the surface sediments that correspond to the recent decades when air temperatures have warmed, the mean size of valves in the diatom community has significantly decreased due to an increase in the proportion of smaller-sized planktonic diatom species.

  16. Population-level correlates of preterm delivery among black and white women in the U.S.

    Directory of Open Access Journals (Sweden)

    Suzan L Carmichael

    Full Text Available OBJECTIVE: This study examined the ability of social, demographic, environmental and health-related factors to explain geographic variability in preterm delivery among black and white women in the US and whether these factors explain black-white disparities in preterm delivery. METHODS: We examined county-level prevalence of preterm delivery (20-31 or 32-36 weeks gestation among singletons born 1998-2002. We conducted multivariable linear regression analysis to estimate the association of selected variables with preterm delivery separately for each preterm/race-ethnicity group. RESULTS: The prevalence of preterm delivery varied two- to three-fold across U.S. counties, and the distributions were strikingly distinct for blacks and whites. Among births to blacks, regression models explained 46% of the variability in county-level risk of delivery at 20-31 weeks and 55% for delivery at 32-36 weeks (based on R-squared values. Respective percentages for whites were 67% and 71%. Models included socio-environmental/demographic and health-related variables and explained similar amounts of variability overall. CONCLUSIONS: Much of the geographic variability in preterm delivery in the US can be explained by socioeconomic, demographic and health-related characteristics of the population, but less so for blacks than whites.

  17. Inland hypersaline lakes and the brine shrimp Artemia as simple models for biodiversity analysis at the population level

    Science.gov (United States)

    Gajardo, Gonzalo M; Sorgeloos, Patrick; Beardmore, John A

    2006-01-01

    Biodiversity can be measured at different hierarchical levels, from genetic diversity within species to diversity of ecosystems, though policy-makers tend to use species richness. The 2010 goal of reducing biodiversity loss, agreed by the subscribers to the Convention on Biological Diversity, requires simple and reliable protocols to evaluate biodiversity at any level in a given ecosystem. Stakeholders, particularly policy makers, need to understand how ecosystem components interact to produce social and economic benefits on the long run, whilst scientists are expected to fulfil this demand by testing and modelling ideally simple (low diversity) ecosystems, and by monitoring key species. This work emphasizes the unique opportunity offered by inland, isolated salt lakes and the brine shrimp Artemia, an example of biodiversity contained at the intra-specific level, as simple models to understand and monitor biodiversity, as well as to assess its predicted positive association with ecosystem stability. In addition to having well identified species and strains and even clones, that allow to test reproductive effects (sexual versus asexual), Artemia benefits from the possibility to set up experimental testing at both laboratory scale and outdoor pond systems, for which a comprehensive cyst bank with sufficient amount of samples from all over the world is available. PMID:17132175

  18. Differential correlation of suicide and homicide rates according to geographical areas: A study with population-level data.

    Science.gov (United States)

    Fountoulakis, Konstantinos N; Gonda, Xenia

    2017-03-01

    The current study investigated the relationship of suicide and homicide rates internationally. WHO database mortality data for 82 countries concerning suicide, homicides, and cancer and traffic accidents as controls were used. The analysis included Pearson correlation and multiple linear regression analysis. Worldwide homicidal rates explained 55.42%, 43.86% and 41.7% of male and 22.0%, 22.14% and 13.25% of female suicides for 2000, 2005 and 2010 respectively. In Europe there was a positive correlation between male suicide rates and all homicide rates including homicide rates in both genders, in male victims, and in female victims. In America there is no significant correlation. In Asia there is a significant correlation of male suicidal rates only with homicide rates of female victims. We observed marked and interesting differences in the pattern of association between Europe and the Americas. Overall the current paper suggests that at least in some human populations, suicidality and homicidality share common etiopathogenetic substrates and could be triggered by the same internal or external events or might develop based on common genetic background. Empirically it has been suggested that suicide is related to higher living standards while murder is related to poor quality of life and lower living standards. Copyright © 2017 Elsevier Ireland Ltd. All rights reserved.

  19. Relationship between out-of-home care placement history characteristics and educational achievement: A population level linked data study.

    Science.gov (United States)

    Maclean, Miriam J; Taylor, Catherine L; O'Donnell, Melissa

    2017-08-01

    Studies generally show children who have entered out-of-home care have worse educational outcomes than the general population, although recent research suggests maltreatment and other adversities are major contributing factors. Children's out-of-home care experiences vary and may affect their outcomes. This study examined the influence of placement stability, reunification, type of care, time in care and age at entry to care on children's educational outcomes. We conducted a population-based record-linkage study of children born in Western Australia between 1990 and 2010 who sat State or national Year 3 reading achievement tests (N=235,045 children, including 2160 children with a history of out-of-home care). Children's educational outcomes varied with many aspects of their care experience. Children placed in residential care were particularly likely to have low scores, with an unadjusted OR 6.81, 95% CI[4.94, 9.39] for low reading scores, which was partially attenuated after adjusting for background risk factors but remained significant (OR=1.50, 95% CIs [1.08, 2.08]). Reading scores were also lower for children who had experienced changes in care arrangements in the year of the test. A dose-response effect for multiple placements was expected but not found. Older age at entering care was also associated with worse reading scores. Different characteristics of a child's care history were interwoven with each other as well as child, family and neighbourhood characteristics, highlighting a need for caution in attributing causality. Although the level of educational difficulties varied, the findings suggest a widespread need for additional educational support for children who have entered care, including after reunification. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Place of death of people living with Parkinson's disease: a population-level study in 11 countries.

    Science.gov (United States)

    Moens, Katrien; Houttekier, Dirk; Van den Block, Lieve; Harding, Richard; Morin, Lucas; Marchetti, Stefano; Csikos, Agnes; Loucka, Martin; Naylor, Wayne A; Wilson, Donna M; Teno, Joan; Cardenas-Turanzas, Marylou; Rhee, YongJoo; Garcia-Leon, Francisco Javier; Deliens, Luc; Cohen, Joachim

    2015-05-20

    Most people prefer to receive end-of-life care in familiar surroundings rather than in hospital. This study examines variation in place of death for people dying from Parkinson's disease (PD) across 11 European and non-European countries. Using death certificate data of 2008 for Belgium, France, Italy, Hungary, Czech Republic, New Zealand, USA, Canada, Mexico, South Korea and Spain for all deaths with PD as an underlying cause (ICD-10 code: G20) cross-national differences in place of death were examined. Associations between place of death and patient socio-demographic and regional characteristics were evaluated using multivariable binary logistic regression analyses. The proportion of deaths in hospital ranged from 17% in the USA to 75% in South Korea. Hospital was the most prevalent place of death in France (40%), Hungary (60%) and South Korea; nursing home in New Zealand (71%), Belgium (52%), USA (50%), Canada (48%) and Czech Republic (44%); home in Mexico (73%), Italy (51%) and Spain (46%). The chances of dying in hospital were consistently higher for men (Belgium, France, Italy, USA, Canada), those younger than 80 years (Belgium, France, Italy, USA, Mexico), and those living in areas with a higher provision of hospital beds (Italy, USA). In several countries a substantial proportion of deaths from PD occurs in hospitals, although this may not be the most optimal place of terminal care and death. The wide variation between countries in the proportion of deaths from PD occurring in hospital indicates a potential for many countries to reduce these proportions.

  1. Individual and Population Level Resource Selection Patterns of Mountain Lions Preying on Mule Deer along an Urban-Wildland Gradient

    Science.gov (United States)

    Benson, John F.; Sikich, Jeff A.; Riley, Seth P. D.

    2016-01-01

    Understanding population and individual-level behavioral responses of large carnivores to human disturbance is important for conserving top predators in fragmented landscapes. However, previous research has not investigated resource selection at predation sites of mountain lions in highly urbanized areas. We quantified selection of natural and anthropogenic landscape features by mountain lions at sites where they consumed their primary prey, mule deer (Odocoileus hemionus), in and adjacent to urban, suburban, and rural areas in greater Los Angeles. We documented intersexual and individual-level variation in the environmental conditions present at mule deer feeding sites relative to their availability across home ranges. Males selected riparian woodlands and areas closer to water more than females, whereas females selected developed areas marginally more than males. Females fed on mule deer closer to developed areas and farther from riparian woodlands than expected based on the availability of these features across their home ranges. We suggest that mortality risk for females and their offspring associated with encounters with males may have influenced the different resource selection patterns between sexes. Males appeared to select mule deer feeding sites mainly in response to natural landscape features, while females may have made kills closer to developed areas in part because these are alternative sites where deer are abundant. Individual mountain lions of both sexes selected developed areas more strongly within home ranges where development occurred less frequently. Thus, areas near development may represent a trade-off for mountain lions such that they may benefit from foraging near development because of abundant prey, but as the landscape becomes highly urbanized these benefits may be outweighed by human disturbance. PMID:27411098

  2. Estimation of HIV-testing rates to maximize early diagnosis-derived benefits at the individual and population level.

    Science.gov (United States)

    Dilernia, Dario A; Monaco, Daniela C; Cesar, Carina; Krolewiecki, Alejandro J; Friedman, Samuel R; Cahn, Pedro; Salomon, Horacio

    2013-01-01

    In HIV infection, initiation of treatment is associated with improved clinical outcom and reduced rate of sexual transmission. However, difficulty in detecting infection in early stages impairs those benefits. We determined the minimum testing rate that maximizes benefits derived from early diagnosis. We developed a mathematical model of HIV infection, diagnosis and treatment that allows studying both diagnosed and undiagnosed populations, as well as determining the impact of modifying time to diagnosis and testing rates. The model's external consistency was assessed by estimating time to AIDS and death in absence of treatment as well as by estimating age-dependent mortality rates during treatment, and comparing them with data previously reported from CASCADE and DHCS cohorts. In our model, life expectancy of patients diagnosed before 8 years post infection is the same as HIV-negative population. After this time point, age at death is significantly dependent on diagnosis delay but initiation of treatment increases life expectancy to similar levels as HIV-negative population. Early mortality during HAART is dependent on treatment CD4 threshold until 6 years post infection and becomes dependent on diagnosis delay after 6 years post infection. By modifying testing rates, we estimate that an annual testing rate of 20% leads to diagnosis of 90% of infected individuals within the first 8.2 years of infection and that current testing rate in middle-high income settings stands close to 10%. In addition, many differences between low-income and middle-high incomes can be predicted by solely modifying the diagnosis delay. To increase testing rate of undiagnosed HIV population by two-fold in middle-high income settings will minimize early mortality during initiation of treatment and global mortality rate as well as maximize life expectancy. Our results highlight the impact of achieving early diagnosis and the importance of strongly work on improving HIV testing rates.

  3. Estimation of HIV-testing rates to maximize early diagnosis-derived benefits at the individual and population level.

    Directory of Open Access Journals (Sweden)

    Dario A Dilernia

    Full Text Available In HIV infection, initiation of treatment is associated with improved clinical outcom and reduced rate of sexual transmission. However, difficulty in detecting infection in early stages impairs those benefits. We determined the minimum testing rate that maximizes benefits derived from early diagnosis.We developed a mathematical model of HIV infection, diagnosis and treatment that allows studying both diagnosed and undiagnosed populations, as well as determining the impact of modifying time to diagnosis and testing rates. The model's external consistency was assessed by estimating time to AIDS and death in absence of treatment as well as by estimating age-dependent mortality rates during treatment, and comparing them with data previously reported from CASCADE and DHCS cohorts.In our model, life expectancy of patients diagnosed before 8 years post infection is the same as HIV-negative population. After this time point, age at death is significantly dependent on diagnosis delay but initiation of treatment increases life expectancy to similar levels as HIV-negative population. Early mortality during HAART is dependent on treatment CD4 threshold until 6 years post infection and becomes dependent on diagnosis delay after 6 years post infection. By modifying testing rates, we estimate that an annual testing rate of 20% leads to diagnosis of 90% of infected individuals within the first 8.2 years of infection and that current testing rate in middle-high income settings stands close to 10%. In addition, many differences between low-income and middle-high incomes can be predicted by solely modifying the diagnosis delay.To increase testing rate of undiagnosed HIV population by two-fold in middle-high income settings will minimize early mortality during initiation of treatment and global mortality rate as well as maximize life expectancy. Our results highlight the impact of achieving early diagnosis and the importance of strongly work on improving HIV

  4. Health utilities in people with chronic pain using a population-level survey and linked health care administrative data.

    Science.gov (United States)

    Hogan, Mary-Ellen; Taddio, Anna; Katz, Joel; Shah, Vibhuti; Krahn, Murray

    2017-03-01

    Health utilities are a preference-based measure of health-related quality of life that facilitates comparison of disease burden across conditions. We estimated utilities using a population-based, matched sample of adolescents and adults with and without chronic pain, controlling for comorbidity. Ontarians aged ≥12 years with and without chronic pain were identified from the Canadian Community Health Survey (CCHS) 2000-2001 and 2009-2010 and linked to their provincial health care administrative data. Individuals with chronic pain were matched to those without using age, sex, survey year, and a propensity score for having chronic pain estimated from a rurality index, income quintile, and comorbidity. The Health Utilities Index Mark 3 instrument, included in the Canadian Community Health Survey, was used. Mean utilities were calculated for each group. Utility decrement for chronic pain was also calculated for each matched pair. A total of 65,246 responses were available for analysis. After matching, there were 12,146 matched pairs with and without pain. In the matched cohort, mean age was 54 years (SD 12); 61% were female. The matched cohort with chronic pain had a mean utility of 0.59 (95% confidence interval 0.58-0.59), and the decrement associated with chronic pain was 0.32 (95% confidence interval 0.31-0.32). Utilities in people with chronic pain were lower than, and decrements larger than, those seen with most other chronic diseases including heart disease, diabetes, and chronic obstructive pulmonary disease. These data will be useful to inform priorities and future strategies for the prevention and control of chronic pain.

  5. The culturable intestinal microbiota of triploid and diploid juvenile Atlantic salmon (Salmo salar - a comparison of composition and drug resistance

    Directory of Open Access Journals (Sweden)

    Cantas Leon

    2011-11-01

    Full Text Available Abstract Background With the increased use of ploidy manipulation in aquaculture and fisheries management this investigation aimed to determine whether triploidy influences culturable intestinal microbiota composition and bacterial drug resistance in Atlantic salmon (Salmo salar. The results could provide answers to some of the physiological differences observed between triploid and diploid fish, especially in terms of fish health. Results No ploidy effect was observed in the bacterial species isolated, however, triploids were found to contain a significant increase in total gut microbiota levels, with increases in Pseudomonas spp., Pectobacterium carotovorum, Psychrobacter spp., Bacillus spp., and Vibrio spp., (12, 42, 9, 10, and 11% more bacteria in triploids than diploids, respectively, whereas a decrease in Carnobacterium spp., within triploids compared to diploids was close to significant (8% more bacteria in diploids. With the exception of gentamicin, where no bacterial resistance was observed, bacterial isolates originating from triploid hosts displayed increased resistance to antibacterials, three of which were significant (tetracycline, trimethoprim, and sulphonamide. Conclusion Results indicate that triploidy influences both the community and drug resistance of culturable intestinal microbiota in juvenile salmon. These results demonstrate differences that are likely to contribute to the health of triploid fish and have important ramifications on the use of antibacterial drugs within aquaculture.

  6. Skeletal muscle protease activities in the early growth and development of wild Atlantic salmon (Salmo salar L.).

    Science.gov (United States)

    Lysenko, Liudmila A; Kantserova, Nadezda P; Kaivarainen, Elena I; Krupnova, Marina Yu; Nemova, Nina N

    2017-09-01

    Growth-related dynamics of intracellular protease activities in four year classes of the Atlantic salmon (Salmo salar L. 1758) parr and smolts inhabiting salmon rivers of northwestern Russia (the White Sea basin) were studied. Cathepsin B, cathepsin D, proteasome, and calpain activities in the skeletal muscles of salmon were assessed to investigate their relative contribution to the total protein degradation as well as to young fish growth process. It was confirmed that calpain activity dominates in salmon muscles while proteasome plays a minor role, in contrast to terrestrial vertebrates. Calpain and proteasome activities were maximal at the early post-larval stage (in parrs 0+) and declined with age (parrs 1+ through 2+) dropping to the lowest level in salmon smolts. Annual growth increments and proteolytic activities of calpains and proteasome in the muscles of salmon juveniles changed with age in an orchestrated manner, while lysosomal cathepsin activities increased with age. Comparing protease activities and growth increments in salmon parr and smolts we suggested that the partial suppression of the protein degradation could be a mechanism stimulating efficient growth in smoltifying salmon. Growth and smoltification-related dynamics of protease activities was quite similar in salmon populations from studied spawning rivers, such as Varzuga and Indera; however, some habitat-related differences were observed. Growth increments and protease activities varied in salmon parr 0+ (but not on later ages) inhabiting either main rivers or small tributaries apparently due to habitat difference on the resources for fish growth. Copyright © 2017 Elsevier Inc. All rights reserved.

  7. Paranucleospora theridion (Microsporidia) infection dynamics in farmed Atlantic salmon Salmo salar put to sea in spring and autumn.

    Science.gov (United States)

    Sveen, S; Øverland, H; Karlsbakk, E; Nylund, A

    2012-10-10

    The microsporidian Paranucleospora theridion (syn. Desmozoon lepeophtheirii) is a parasite of Atlantic salmon Salmo salar and also a hyperparasite of the salmon louse Lepeophtheirus salmonis. The parasite develops 2 types of spores in salmon, cytoplasmic spores in phagocytes and intranuclear spores in epidermal cells. The former type of development is assumed to be propagative (autoinfection), while the epidermal spores transfer the parasite to lice. Development in lice is extensive, with the formation of xenoma-like hypertrophic cells filled with microsporidian spores. We show that salmon are infected in the absence of lice, likely through waterborne spores that initiate infections in the gills. During summer and autumn the parasite propagates in the kidney, as evidenced by peaking normalised expression of P. theridion rRNA. Lice become infected during autumn, and develop extensive infections during winter. Lice mortality in winter and spring is likely responsible for a reservoir of spores in the water. Salmon transferred to sea in November (low temperature) did not show involvement of the kidney in parasite propagation and lice on such fish did not become infected. Apparently, low temperatures inhibit normal P. theridion development in salmon.

  8. Negligible differences in metabolism and thermal tolerance between diploid and triploid Atlantic salmon (Salmo salarL.).

    Science.gov (United States)

    Bowden, A J; Andrewartha, S J; Elliott, N G; Frappell, P B; Clark, T D

    2018-01-04

    The mechanisms that underlie thermal tolerance in aquatic ectotherms remain unresolved. Triploid fish have been reported to exhibit lower thermal tolerance than diploids, offering a potential model organism to better understand the physiological drivers of thermal tolerance. Here, we compared triploid and diploid juvenile Atlantic salmon ( Salmo salar ) in freshwater to investigate the proposed link between aerobic capacity and thermal tolerance. We measured specific growth rates (SGR) and resting (aerobic) metabolic rates (RMR) in freshwater at 3, 7 and 9 weeks of acclimation to either 10, 14 or 18°C. Additionally, maximum metabolic rates (MMR) were measured at 3 and 7 weeks of acclimation, and critical thermal maxima (CT max ) were measured at 9 weeks. Mass, SGR, and RMR differed between ploidies across all temperatures at the beginning of the acclimation period, but all three metrics converged between ploidies by week 7. Aerobic scope (MMR - RMR) remained consistent across ploidies, acclimation temperatures, and time. At 9 weeks, CT max was independent of ploidy, but correlated positively with acclimation temperature despite the similar aerobic scope between acclimation groups. Our findings suggest that acute thermal tolerance is not modulated by aerobic scope, and the altered genome of triploid Atlantic salmon does not translate to reduced thermal tolerance of juvenile fish in freshwater. © 2018. Published by The Company of Biologists Ltd.

  9. Atlantic salmon reovirus infection causes a CD8 T cell myocarditis in Atlantic salmon (Salmo salar L..

    Directory of Open Access Journals (Sweden)

    Aase B Mikalsen

    Full Text Available Heart and skeletal inflammation (HSMI of farmed Atlantic salmon (Salmo salar L. is a disease characterized by a chronic myocarditis involving the epicardium and the compact and spongious part of the heart ventricle. Chronic myositis of the red skeletal muscle is also a typical finding of HSMI. Piscine reovirus (PRV has been detected by real-time PCR from farmed and wild salmon with and without typical changes of HSMI and thus the causal relationship between presence of virus and the disease has not been fully determined. In this study we show that the Atlantic salmon reovirus (ASRV, identical to PRV, can be passaged in GF-1 cells and experimental challenge of naïve Atlantic salmon with cell culture passaged reovirus results in cardiac and skeletal muscle pathology typical of HSMI with onset of pathology from 6 weeks, peaking by 9 weeks post challenge. ASRV replicates in heart tissue and the peak level of virus replication coincides with peak of heart lesions. We further demonstrate mRNA transcript assessment and in situ characterization that challenged fish develop a CD8+ T cell myocarditis.

  10. The effect of stunning methods and season on muscle texture hardness in Atlantic salmon (Salmo salar L.).

    Science.gov (United States)

    Merkin, Grigory V; Stien, Lars Helge; Pittman, Karin; Nortvedt, Ragnar

    2014-06-01

    Commercially collected records of Atlantic salmon (Salmo salar L.) muscle texture hardness were used to evaluate the effect of slaughter procedures and seasonality on texture quality. A database collected by Marine Harvest® contained flesh hardness records of Atlantic salmon slaughtered at processing plants in Norway from summer 2010 to summer 2011. The fish were slaughtered either by (1) percussion followed by automated bleeding ("Percussive") or (2) live chilling with exposure to carbon dioxide (CO2 ) followed by manual severing gill arches and bleeding ("CO2 ") or (3) live chilling with exposure to CO2 followed by percussive stunning and at the end automated bleeding ("CO2 ·percussive"). Hardness in salmon muscle cutlets was measured in Newtons (N) by Materials Testing Machine Zwick 500N. The hardness in salmon varied significantly over the study period (P hardness (P < 0.05, mixed effect model), where percussion followed by automated bleeding resulted in the hardest value (24.0 ± 0.4 N) as compared with CO2 stunning (21.8 ± 0.2 N) and combination of CO2 and percussive stunning (23.1 ± 0.15 N). CO2 is suspected as a causal factor in accelerated postmortem softening of the salmon muscle. Commercial use of CO2 in combination with live chilling results in accelerated postmortem softening of the muscle tissue in salmon and should be avoided. © 2014 Institute of Food Technologists®

  11. A non-lethal method to estimate CYP1A expression in laboratory and wild Atlantic salmon (Salmo salar)

    Science.gov (United States)

    Rees, C.B.; McCormick, S.D.; Li, W.

    2005-01-01

    Expression of cytochrome P4501A (CYP1A) has been used as a biomarker for possible exposure to contaminants such as PCBs and dioxins in teleost fish. Using a quantitative reverse transcription-polymerase chain reaction (Q-RT-PCR) and a non-lethal gill biopsy, we estimated levels of CYP1A mRNA expression in Atlantic salmon (Salmo salar). Groups of ten Atlantic salmon juveniles (48–76 g) received an intraperitoneal injection of 50 μg g− 1 β-naphthoflavone (BNF) or vehicle. Their gill tissues were repeatedly sampled by non-lethal biopsies on day 0, 1, 2 and 7. Control fish expressed basal levels of CYP1A over the duration of sampling. BNF-treated salmon demonstrated similar levels of CYP1A to control fish at day 0 and higher levels over the course of each additional sampling point. Gill biopsies from wild salmon sampled from Millers River (South Royalston, Worcester County, MA, USA), known to contain PCBs, showed significantly higher CYP1A levels over an uncontaminated reference stream, Fourmile Brook (Northfield, Franklin County, MA, USA). We conclude that gill biopsies coupled with Q-RT-PCR analysis is a valuable tool in environmental assessment of wild Atlantic salmon populations and has the potential to be applied to other populations of fish as well.

  12. Sequential protein extraction as an efficient method for improved proteome coverage in larvae of Atlantic salmon (Salmo salar).

    Science.gov (United States)

    Nuez-Ortín, Waldo G; Carter, Chris G; Nichols, Peter D; Wilson, Richard

    2016-07-01

    Understanding diet- and environmentally induced physiological changes in fish larvae is a major goal for the aquaculture industry. Proteomic analysis of whole fish larvae comprising multiple tissues offers considerable potential but is challenging due to the very large dynamic range of protein abundance. To extend the coverage of the larval phase of the Atlantic salmon (Salmo salar) proteome, we applied a two-step sequential extraction (SE) method, based on differential protein solubility, using a nondenaturing buffer containing 150 mM NaCl followed by a denaturing buffer containing 7 M urea and 2 M thiourea. Extracts prepared using SE and one-step direct extraction were characterized via label-free shotgun proteomics using nanoLC-MS/MS (LTQ-Orbitrap). SE partitioned the proteins into two fractions of approximately equal amounts, but with very distinct protein composition, leading to identification of ∼40% more proteins than direct extraction. This fractionation strategy enabled the most detailed characterization of the salmon larval proteome to date and provides a platform for greater understanding of physiological changes in whole fish larvae. The MS data are available via the ProteomeXchange Consortium PRIDE partner repository, dataset PXD003366. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Consistency of standard metabolic rate in relation to life history strategy of juvenile Atlantic salmon Salmo salar.

    Science.gov (United States)

    Seppänen, Eila; Piironen, Jorma; Huuskonen, Hannu

    2010-06-01

    Temporal consistency of relative standard metabolic rate (rSMR) of individual Atlantic salmon Salmo salar juveniles in three stocks was investigated. The stocks differed in their geographical origin and natal habitat (fresh water, brackish water, seawater). Oxygen consumption measurements of hatchery-reared fish hatched in February 2005 were conducted three times: in early spring 2006, in autumn 2006, and in late spring 2007. The results partly disagreed and partly agreed with earlier studies, in which temporal consistency of SMR in juvenile salmonids have been addressed. In the first period from early spring to autumn, no correlation between rSMR statuses of individuals was found whereas in the second period from autumn to late spring, fish were mainly observed to maintain their relative SMR level indicating a significant repeatability of individual rSMR status over the latter period. Furthermore, a relationship between rSMR status and life history strategy was found: post-smolts and smolts had higher SMR than non-smolts. Copyright 2010 Elsevier Inc. All rights reserved.

  14. Regulation of the glucocorticoid receptor mRNA levels in the gills of Atlantic salmon (Salmo salar during smoltification

    Directory of Open Access Journals (Sweden)

    MAZURAIS D.

    1998-07-01

    Full Text Available The regulation of the Glucocorticoid Receptor (GR transcript was investigated in the gills of Atlantic salmon (Salmo salar during the parr-smolt transformation. Sampling of parr and smolt fish was performed between December and July and in particular during the smoltification period occurring in spring. Quantification of GR transcripts revealed differences between the two groups in March and at the beginning of April. During these dates, the amounts of GR mRNA in parr gills were respectively three and two fold lower than those measured in smolts. In order to determine which factors are responsible for these differences, we studied the long-term effects of prolactin and Cortisol treatments on GR transcript in the gills of presmolt fish. The plasma levels of these two hormones respectively drop and rise during smoltification. Contrary to Cortisol long-term treatment which did not modify the amount of gill GR transcript, short-term treatment induced a significant decrease within 12 hours. Prolactin long-term treatment caused a significant increase of GR transcript abundance after 13 days of implant treatment. This result is unexpected with regard to those obtained in the smoltification analysis but is in agreement with previous studies performed in mammary gland revealing a positive control of PRL on GR in epithelial cells. Our data suggest that the regulation of the GR transcript during the parr-smolt transformation probably involves several hormonal factors.

  15. Somatosensory evoked potentials in the telencephalon of Atlantic salmon (Salmo salar) following galvanic stimulation of the tail.

    Science.gov (United States)

    Nordgreen, Janicke; Horsberg, Tor Einar; Ranheim, Birgit; Chen, Andrew C N

    2007-12-01

    Electric activity in the brain which is time-locked to a given stimulation of the somatosensory system can be recorded as a somatosensory evoked potential (SEP). We investigated whether a galvanic stimulation of the tail base in Atlantic salmon (Salmo salar) would elicit a SEP in the telencephalon. The telencephalon is central in learning and memory, and activity here may be a prerequisite for processing of external stimuli on a cognitive or emotional level. Anaesthetized salmon (n = 11) were subjected to craniotomy and a recording electrode was inserted into the telencephalon. The fish were given stimulations of four intensities, i.e., 2, 5, 10 and 20 mA. A SEP was elicited in the contralateral dorsal telencephalon for all intensities. This result agrees with findings in other fish species. Furthermore, there was a significant difference between the maximum peak amplitude and mean amplitude of the SEP elicited by putative non-noxious (2 mA) and putative noxious (20 mA) stimulation intensities (P stimulation intensities also tend to introduce longer-latencies components in the SEP. The results added to the body of literature indicates that the exteroceptive senses are represented by processing within the telencephalon of the fish.

  16. Carbon monoxide as stunning/killing method on farmed Atlantic salmon (Salmo salar): effects on lipid and cholesterol oxidation.

    Science.gov (United States)

    Secci, Giulia; Serra, Andrea; Concollato, Anna; Conte, Giuseppe; Mele, Marcello; Olsen, Rolf E; Parisi, Giuliana

    2016-05-01

    Carbon monoxide (CO) has been recently utilized as a new stunning/killing procedure for Atlantic salmon (Salmo salar). Its effects on lipid and cholesterol oxidation of farmed Atlantic salmon fillets were evaluated at two times of refrigerated (2.5 °C) storage, T0 (64 h after death) and T14 (14 days from T0). The use of CO was compared with the commonly utilized percussion (P) method. Fatty acid profile, primary (conjugated dienes) and secondary (TBARS) oxidation products, cholesterol oxidation products (COPs) and carotenoids were unaffected by the killing method. Despite the low oxidative status of lipid (0.66 and 0.60 mg malondialdehyde kg(-1) muscle in P and CO fish respectively), cholesterol was found to be highly oxidized (0.17 and 0.13 mg COPs kg(-1) ). Storage significantly affected oxidative stability of fish muscle by increasing oxidation products. Interestingly, TBARS content doubled while the increase for COPs was not homogeneous: α- and β-epoxycholesterol increased by 25%, whereas triol and 7-ketocholesterol increased by 48 and 62% respectively. The quality of salmon fillets just after slaughtering and after 14 days of refrigerated storage at 2.5 °C did not change, irrespective of the killing method adopted, suggesting that the CO method may be applied without any detrimental effect on the quality of fish fillets. © 2015 Society of Chemical Industry. © 2015 Society of Chemical Industry.

  17. The effect of light on the settlement of the salmon louse, Lepeophtheirus salmonis, on Atlantic salmon, Salmo salar L.

    Science.gov (United States)

    Browman, H I; Boxaspen, K; Kuhn, P

    2004-12-01

    The salmon louse, Lepeophtheirus salmonis, is an ectoparasitic copepod that infests both wild and farmed salmonid fish. Salmon lice are a major disease problem in the farming of Atlantic salmon, Salmo salar L., and the possibility of salmon lice playing a role in the decline of wild anadromous stocks has also been raised. Lepeophtheirus salmonis can detect a range of stimuli (pressure/moving water, chemicals and light) in the external environment. However, the response thresholds to various stimuli, and the spatial and temporal scales over which they operate in the context of host location, are largely unknown. In this context, we attempted to determine whether salmon lice copepodids settle onto hosts more effectively, or at different locations on the fish's body, under different qualities of light. Lice settlement trials were conducted under three lighting conditions; L1: unpolarized under ultraviolet A (UVA)-through visible; L2: unpolarized without UVA (control); L3: 100% linearly polarized without UVA. A dark control was also conducted. No statistically significant difference in lice settlement was found. While changes in light intensity are involved in host detection at spatial scales on the order of metres, the results presented here suggest that it is not the primary sensory modality underlying host location at smaller spatial scales (cm to mm).

  18. Histological changes in intestine of Atlantic salmon (Salmo salar L.) following in vitro exposure to pathogenic and probiotic bacterial strains.

    Science.gov (United States)

    Ringø, E; Salinas, I; Olsen, R E; Nyhaug, A; Myklebust, R; Mayhew, T M

    2007-04-01

    Furunculosis and vibriosis are diseases that cause severe economic losses in the fish-farming industry. The foregut of the Atlantic salmon (Salmo salar L.) was exposed in vitro to two fish pathogens, Aeromonas salmonicida (causative agent of furunculosis) and Vibrio anguillarum (causative agent of vibriosis), and to one probiotic strain, Carnobacterium divergens, at 6 x 10(4) or 6 x 10(6) viable bacteria per milliliter. Histological changes following bacterial exposure were assessed by light and electron microscopy. Control samples (foregut exposed to Ringer's solution only) and samples exposed only to C. divergens had a similar appearance to intact intestinal mucosal epithelium, with no signs of damage. However, exposure of the foregut to the pathogenic bacteria resulted in damaged epithelial cells, cell debris in the lumen, and disorganization of the microvilli. Co-incubation of the foregut with a pathogen and C. divergens did not reverse the damaging effects caused by the pathogen, although these were alleviated when probiotic bacteria were used. Based on these results, we suggest that the probiotic bacterium, C. divergens, is able to prevent, to some extent, pathogen-induced damage in the Atlantic salmon foregut.

  19. Ectoparasite Caligus rogercresseyi modifies the lactate response in Atlantic salmon (Salmo salar) and Coho salmon (Oncorhynchus kisutch).

    Science.gov (United States)

    Vargas-Chacoff, L; Muñoz, J L P; Hawes, C; Oyarzún, R; Pontigo, J P; Saravia, J; González, M P; Mardones, O; Labbé, B S; Morera, F J; Bertrán, C; Pino, J; Wadsworth, S; Yáñez, A

    2017-08-30

    Although Caligus rogercresseyi negatively impacts Chilean salmon farming, the metabolic effects of infection by this sea louse have never been completely characterized. Therefore, this study analyzed lactate responses in the plasma, as well as the liver/muscle lactate dehydrogenase (LDH) activity and gene expression, in Salmo salar and Oncorhynchus kisutch infested by C. rogercresseyi. The lactate responses of Atlantic and Coho salmon were modified by the ectoparasite. Both salmon species showed increasing in plasma levels, whereas enzymatic activity increased in the muscle but decreased in the liver. Gene expression was overexpressed in both Coho salmon tissues but only in the liver for Atlantic salmon. These results suggest that salmonids need more energy to adapt to infection, resulting in increased gene expression, plasma levels, and enzyme activity in the muscles. The responses differed between both salmon species and over the course of infection, suggesting potential species-specific responses to sea-lice infection. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. Quaternary shortening in the central Puna Plateau of NW Argentina: Preliminary results from the Salar de Pocitos, Salta province (24.5° S, 67° W)

    Science.gov (United States)

    Freymark, Jessica; Strecker, Manfred R.; Bookhagen, Bodo; Bekeschus, Benjamin; Eckelmann, Felix; Alonso, Ricardo

    2013-04-01

    Active tectonism in Cenozoic orogenic plateaus is often characterized by a combination of active extensional and strike-slip faulting subsequent to protracted phases of shortening and the build-up of high topography. In the Puna Plateau of NW Argentina, the southern part of the world's second largest orogenic plateau, the changeover from shortening to extensional tectonics is thought to have occured between 7 and 5 Ma along the southeastern plateau margin, while the central and northern plateau areas apparently changed into an extensional regime between 9 and 6 Ma (Cladouhos et al., 1994). Despite these observations of extensional structures we report on new data from the Salar de Pocitos that show sustained shortening in the south-central part of the plateau. The south-central Puna Plateau is characterized by an average elevation of about 3700 m with low relief and internally drained basins, which are bordered by reverse-fault bounded ranges. The N-S oriented Salar de Pocitos is an integral part of these contractional structures and covers an area of ~435 km². The western border of the basin constitutes the eastern flank of an anticline involving Tertiary and Quaternary sediments, while the eastern border is delimited by a N-S striking reverse fault, bounding the range front of the Sierra Qda. Honda. In the north of the Salar de Pocitos the three Miocene volcanoes Tultul, Delmedio and Pocitos form a barrier with the Salar del Rincón, and the south of the basin is bordered by fault blocks involving Ordovician lithologies that have left only a narrow valley that may have provided an outlet of the basin in the past. Multiple terraces generated during Late Pleistocene and Holocene lake highstands straddle the Pocitos Basin and serve as excellent strain markers to assess neotectonic deformation. We surveyed the terraces along N-S and E-W transects using a differential GPS. The E-W surveys are perpendicular to the structures that bound the basin and record

  1. Determining the best population-level alcohol consumption model and its impact on estimates of alcohol-attributable harms

    Directory of Open Access Journals (Sweden)

    Kehoe Tara

    2012-04-01

    Full Text Available Abstract Background The goals of our study are to determine the most appropriate model for alcohol consumption as an exposure for burden of disease, to analyze the effect of the chosen alcohol consumption distribution on the estimation of the alcohol Population- Attributable Fractions (PAFs, and to characterize the chosen alcohol consumption distribution by exploring if there is a global relationship within the distribution. Methods To identify the best model, the Log-Normal, Gamma, and Weibull prevalence distributions were examined using data from 41 surveys from Gender, Alcohol and Culture: An International Study (GENACIS and from the European Comparative Alcohol Study. To assess the effect of these distributions on the estimated alcohol PAFs, we calculated the alcohol PAF for diabetes, breast cancer, and pancreatitis using the three above-named distributions and using the more traditional approach based on categories. The relationship between the mean and the standard deviation from the Gamma distribution was estimated using data from 851 datasets for 66 countries from GENACIS and from the STEPwise approach to Surveillance from the World Health Organization. Results The Log-Normal distribution provided a poor fit for the survey data, with Gamma and Weibull distributions providing better fits. Additionally, our analyses showed that there were no marked differences for the alcohol PAF estimates based on the Gamma or Weibull distributions compared to PAFs based on categorical alcohol consumption estimates. The standard deviation of the alcohol distribution was highly dependent on the mean, with a unit increase in alcohol consumption associated with a unit increase in the mean of 1.258 (95% CI: 1.223 to 1.293 (R2 = 0.9207 for women and 1.171 (95% CI: 1.144 to 1.197 (R2 = 0. 9474 for men. Conclusions Although the Gamma distribution and the Weibull distribution provided similar results, the Gamma distribution is recommended to model alcohol

  2. Molecular analysis of enrichment cultures of ammonia oxidizers from the Salar de Huasco, a high altitude saline wetland in northern Chile

    OpenAIRE

    Dorador, C.; Busekov, A.; Vila, I.; Johannes F Imhoff; Witzel, K.-P.

    2008-01-01

    We analyzed enrichment cultures of ammonia-oxidizing bacteria (AOB) collected from different areas of Salar de Huasco, a high altitude, saline, pH-neutral water body in the Chilean Altiplano. Samples were inoculated into mineral media with 10?mM NH4 + at five different salt concentrations (10, 200, 400, 800 and 1,400?mM NaCl). Low diversity (up to three phylotypes per enrichment) of beta-AOB was detected using 16S rDNA and amoA clone libraries. Growth of beta-AOB was only recorded in a few en...

  3. Attempt to validate breakpoint MIC values estimated from pharmacokinetic data obtained during oxolinic acid therapy of winter ulcer disease in Atlantic salmon ( Salmo salar )

    DEFF Research Database (Denmark)

    Coyne, R.; Bergh, Ø.; Samuelsen, O.

    2004-01-01

    Concentrations of oxolinic acid (OXA) were measured in the plasma, muscle, liver, and kidney of 48 Atlantic salmons (Salmo salar) 1 day after the end of an oral administration. OXA was administered over a period of 13 days to control an outbreak of winter ulcer disease in a commercial marine farm....... On the basis of their behaviour, the fish were classified as healthy (n=18), moribund (n=20), or dead (n=10). There was a dramatic difference in the OXA concentrations in the healthy fish and those classified as moribund or dead. There was no evidence of bacterial infection in the 18 healthy fish, all of which...

  4. Comparison of two pre-enrichments broths for recovering Listeria spp. from salmon (Salmo salar) and salmon-trout (Oncorhynchus mykiss)

    OpenAIRE

    Vaz-Velho,Manuela; Duarte, Gabriela; Gibbs, Paul

    2001-01-01

    Low levels of occurrence of Listeria spp. in fresh salmon (Salmo_salar ) and salmon-trout (Oncorhynchus mykiss), may be related to the selectivity of the pre-enrichment broth recommended by ISO 11290-1. The purpose of this study was to compare the abilities of Fraser base (without supplements) and 0.1% (w/v) peptone water for recovering Listeria spp. from the fresh fish samples. Fifty-six fish were swabbed and the swabs placed in Fraser base and in 0.1% (w/v) peptone water. Samples were a...

  5. Tapetes microbianos del Salar de Llamará, norte de Chile Microbial mats from the Llamará salt flat, northern Chile

    OpenAIRE

    CECILIA DEMERGASSO; GUILLERMO CHONG; PEDRO GALLEGUILLOS; LORENA ESCUDERO; MAIRA MARTíNEZ-ALONSO; ISABEL ESTEVE

    2003-01-01

    Se estudiaron las comunidades estratificadas de microorganismos fotosintéticos que se encuentran en el Salar de Llamará ubicado en el desierto de Atacama, norte de Chile, mediante métodos microscópicos y espectrofotométricos. El espesor de la zona fótica de los tapetes descritos varió entre 8 y 30 mm lo cual podría atribuirse a la granulometría y la composición mineralógica de los sedimentos. Se diferencian tres tipos de tapetes. El primero con una única capa pigmentada de color verde; el seg...

  6. Quality of raw and smoked fillets from clinically healthy Atlantic salmon, Salmo salar L., following an outbreak of pancreas disease (PD)

    DEFF Research Database (Denmark)

    Taksdal, T.; Wiik‐Nielsen, J.; Birkeland, S.

    2012-01-01

    Pancreas disease (PD) is a viral disease of farmed salmonid fish, which causes huge economic losses. Pathological changes in skeletal muscle, pancreas and heart are hallmarks of PD. Stakeholders in the fish‐smoking industry have claimed that fillets from PD‐affected Atlantic salmon, Salmo salar L...... provided a paler raw fillet and a yellowish and harder cold‐smoked fillet than normal. PD had no significant effect on fillet gaping, bacteriological quality or off‐odour development during storage. An unexpected finding was a significant subendocardial fibrosis in 23% of the PD‐affected fish. The latter...

  7. Effects of genotoxicity and its consequences at the population level in sexual and asexual Artemia assessed by analysis of inter-simple sequence repeats (ISSR).

    Science.gov (United States)

    Sukumaran, Sandhya; Grant, Alastair

    2013-09-18

    There is considerable evidence that genetic damage in organisms occurs in the environment as a result of exposure to genotoxins and ionising radiation, but we have limited understanding of the extent to which this results in adverse consequences at a population level. We used inter-simple sequence repeat (ISSR) markers to quantify genotoxic effects of the mutagen ethylmethane sulfonate (EMS) on a sexual (Artemia franciscana) and an asexual (Artemia parthenogenetica) species of brine shrimp. The method provides information similar to that obtained with assessment of RAPD (random amplification of polymorphic DNA) but is more robust. Genetic damage was transmitted to the F1 generation in both Artemia species, but the sexual species showed a greater degree of recovery, as shown by higher values of genomic template stability. There was a strong correlation between DNA damage and effects on individual fitness parameters: size, survival, reproduction and population growth. These effects persisted into the F2 generation in A. parthenogenetica, but in the sexual A. franciscana only effects on fecundity continued beyond the exposed generation, even though there were substantial alterations in ISSR patterns in the F1 generation. Genetic biomarkers can thus be indicative of effects at the population level, but sexually reproducing species have a considerable assimilative capacity for the effects of genotoxins. Copyright © 2013 Elsevier B.V. All rights reserved.

  8. Moritella viscosus infected Atlantic salmon (Salmo salar) express genes during infection associated with quality changes after recovery

    DEFF Research Database (Denmark)

    Ingerslev, Hans-Christian; Nielsen, Michael Engelbrecht

    The gram-negative bacterium Moritella viscosus comprise a huge problem for farmed salmonid fish during cold periods and is the main aetiological agent of winter ulcers. Infection by M. viscosus causes excessive development of punctual lesions in the musculature of the fish, which can cover large...... parts of the body. Infected fish are able to recover and regenerate new skin despite previously heavy wounding. Recovery usually occurs when the water temperature rises above 10-12 °C or the salinity of the water decrease below 12-15 ‰. Regardless of surface/skin recovery, the underlying musculature can...

  9. A NOR-associated repetitive element present in the genome of two Salmo species (Salmo salar and S. trutta)

    Digital Repository Service at National Institute of Oceanography (India)

    Abuin, M.; Clabby, C.; Martinez, P.; Goswami, U.; Flavin, F.; Wilkins, N.P.; Houghton, J.A.; Powell, R.; Sanchez, L.

    , internal repetition, and long direct repeats with deletions and insertions between individual units. The repetitive element was shown to have a tandem unit arrangement and was estimated to occupy between two and three percent of the Atlantic salmon genome...

  10. Expression of gill vacuolar-type H+-ATPase B subunit, and Na+, K+-ATPase alpha- and beta- subunit messenger RNAs in smolting Salmo salar

    DEFF Research Database (Denmark)

    Seidelin, Michel; Madsen, Steffen; Cutler, Christopher P

    2001-01-01

    Changes in gill vacuolar-type H+-ATPase B subunit, and Na+,K+-ATPase alpha and beta subunit mRNA expression were examined during the course of smoltification in Salmo salar. We cloned and sequenced cDNA fragments of S. salar gill i) vacuolar-type H+-ATPase (V-H+-ATPase) B subunit, ii) Na......+,K+-ATPase alpha (1) subunit, and iii) Na+,K+-ATPase beta (1) subunit, and used these as Northern blotting probes. During smoltification, the salmon showed a typical increase in gill Na+,K+-ATPase activity and improved hypo-osmoregulatory ability as judged by their ability to regulate plasma [Cl-] in a 24-hr...... seawater challenge test (35 ppt). Gill Na+,K+-ATPase alpha (1) and beta (1) subunit mRNA levels were regulated at a constant ratio during smoltification. Both transcripts were elevated during the build-up of gill Na+,K+-ATPase activity, underlining the importance of increased mRNA levels for increased...

  11. Salmo salar and Esox lucius full-length cDNA sequences reveal changes in evolutionary pressures on a post-tetraploidization genome

    Directory of Open Access Journals (Sweden)

    Holt Robert A

    2010-04-01

    Full Text Available Abstract Background Salmonids are one of the most intensely studied fish, in part due to their economic and environmental importance, and in part due to a recent whole genome duplication in the common ancestor of salmonids. This duplication greatly impacts species diversification, functional specialization, and adaptation. Extensive new genomic resources have recently become available for Atlantic salmon (Salmo salar, but documentation of allelic versus duplicate reference genes remains a major uncertainty in the complete characterization of its genome and its evolution. Results From existing expressed sequence tag (EST resources and three new full-length cDNA libraries, 9,057 reference quality full-length gene insert clones were identified for Atlantic salmon. A further 1,365 reference full-length clones were annotated from 29,221 northern pike (Esox lucius ESTs. Pairwise dN/dS comparisons within each of 408 sets of duplicated salmon genes using northern pike as a diploid out-group show asymmetric relaxation of selection on salmon duplicates. Conclusions 9,057 full-length reference genes were characterized in S. salar and can be used to identify alleles and gene family members. Comparisons of duplicated genes show that while purifying selection is the predominant force acting on both duplicates, consistent with retention of functionality in both copies, some relaxation of pressure on gene duplicates can be identified. In addition, there is evidence that evolution has acted asymmetrically on paralogs, allowing one of the pair to diverge at a faster rate.

  12. Developmental Hypoxia Has Negligible Effects on Long-Term Hypoxia Tolerance and Aerobic Metabolism of Atlantic Salmon (Salmo salar).

    Science.gov (United States)

    Wood, Andrew T; Clark, Timothy D; Andrewartha, Sarah J; Elliott, Nicholas G; Frappell, Peter B

    Exposure to developmental hypoxia can have long-term impacts on the physiological performance of fish because of irreversible plasticity. Wild and captive-reared Atlantic salmon (Salmo salar) can be exposed to hypoxic conditions during development and continue to experience fluctuating oxygen levels as juveniles and adults. Here, we examine whether developmental hypoxia impacts subsequent hypoxia tolerance and aerobic performance of Atlantic salmon. Individuals at 8°C were exposed to 50% (hypoxia) or 100% (normoxia) dissolved oxygen (DO) saturation (as percent of air saturation) from fertilization for ∼100 d (800 degree days) and then raised in normoxic conditions for a further 15 mo. At 18 mo after fertilization, aerobic scope was calculated in normoxia (100% DO) and acute (18 h) hypoxia (50% DO) from the difference between the minimum and maximum oxygen consumption rates ([Formula: see text] and [Formula: see text], respectively) at 10°C. Hypoxia tolerance was determined as the DO at which loss of equilibrium (LOE) occurred in a constantly decreasing DO environment. There was no difference in [Formula: see text], [Formula: see text], or aerobic scope between fish raised in hypoxia or normoxia. There was some evidence that hypoxia tolerance was lower (higher DO at LOE) in hypoxia-raised fish compared with those raised in normoxia, but the magnitude of the effect was small (12.52% DO vs. 11.73% DO at LOE). Acute hypoxia significantly reduced aerobic scope by reducing [Formula: see text], while [Formula: see text] remained unchanged. Interestingly, acute hypoxia uncovered individual-level relationships between DO at LOE and [Formula: see text], [Formula: see text], and aerobic scope. We discuss our findings in the context of developmental trajectories and the role of aerobic performance in hypoxia tolerance.

  13. Physiological preparedness and performance of Atlantic salmon Salmo salar smolts in relation to behavioural salinity preferences and thresholds

    Science.gov (United States)

    Stich, D.S.; Zydlewski, G.B.; Zydlewski, Joseph D.

    2015-01-01

    This study investigated the relationships between behavioural responses of Atlantic salmon Salmo salarsmolts to saltwater (SW) exposure and physiological characteristics of smolts in laboratory experiments. It concurrently described the behaviour of acoustically tagged smolts with respect to SW and tidal cycles during estuary migration. Salmo salar smolts increased their use of SW relative to fresh water (FW) from April to June in laboratory experiments. Mean preference for SW never exceeded 50% of time in any group. Preference for SW increased throughout the course of smolt development. Maximum continuous time spent in SW was positively related to gill Na+, K+-ATPase (NKA) activity and osmoregulatory performance in full-strength SW (measured as change in gill NKA activity and plasma osmolality). Smolts decreased depth upon reaching areas of the Penobscot Estuary where SW was present, and all fish became more surface oriented during passage from head of tide to the ocean. Acoustically tagged, migrating smolts with low gill NKA activity moved faster in FW reaches of the estuary than those with higher gill NKA activity. There was no difference in movement rate through SW reaches of the estuary based on gill NKA activity. Migrating fish moved with tidal flow during the passage of the lower estuary based on the observed patterns in both vertical and horizontal movements. The results indicate that smolts select low-salinity water during estuary migration and use tidal currents to minimize energetic investment in seaward migration. Seasonal changes in osmoregulatory ability highlight the importance of the timing of stocking and estuary arrival.

  14. Expression of Vibrio salmonicida virulence genes and immune response parameters in experimentally challenged Atlantic salmon (Salmo salar L.

    Directory of Open Access Journals (Sweden)

    Ane Mohn Bjelland

    2013-12-01

    Full Text Available The Gram-negative bacterium Vibrio salmonicida is the causative agent of cold-water vibriosis (CV, a hemorrhagic septicemia that primarily affects farmed Atlantic salmon (Salmo salar L.. The mechanisms of disease development, host specificity and adaptation, as well as the immunogenic properties of V. salmonicida are largely unknown. Therefore, to gain more knowledge on the pathogenesis of CV, 90 Atlantic salmon parr were injected intraperitonellay with 6 x 106 CFU of V. salmonicida LFI1238. Samples from blood and spleen tissue were taken at different time points throughout the challenge for gene expression analysis by two-step reverse transcription quantitative real-time polymerase chain reaction. Out of a panel of six housekeeping genes, accD, gapA and 16S rDNA were found to be the most suitable references for expression analysis in Vibrio salmonicida. The bacterial proliferation during challenge was monitored based on the expression of the 16S rRNA encoding gene. Before day 4, the concentrations of V. salmonicida in blood and spleen tissue demonstrated a lag phase. From day 4, the bacterial proliferation was exponential. The expression profiles of eight genes encoding potential virulence factors of V. salmonicida were studied. Surprisingly, all tested virulence genes were generally highest expressed in broth cultures compared to the in vivo samples. We hypothesize that this general muting of gene expression in vivo may be a strategy for V. salmonicida to hide from the host immune system. To further investigate this hypothesis, the expression profiles of eight genes encoding innate immune factors were analyzed. The results demonstrated a strong and rapid, but short-lasting innate immune response against V. salmonicida. These results suggest that the bacterium possesses mechanisms that inhibit and/or resist the salmon innate immune system until the host becomes exhausted of fighting the on-going and eventually overwhelming infection.

  15. Population dynamics of Vibrio and Pseudomonas species isolated from farmed Tasmanian Atlantic salmon (Salmo salar L.): a seasonal study.

    Science.gov (United States)

    Hatje, Eva; Neuman, Christina; Stevenson, Hollie; Bowman, John P; Katouli, Mohammad

    2014-11-01

    Vibrio and Pseudomonas species have been shown to be part of the normal microbiota of Atlantic salmon (Salmo salar L.), with some strains causing disease in fish. The factors affecting their prevalence and persistence in the salmon gut, however, have not been well studied. In this study, we collected 340 Vibrio and 150 Pseudomonas isolates from the hindgut of farmed Tasmanian Atlantic salmon, fed with two commercially available diets. Samples were collected every 6-8 weeks between July 2011 and May 2012. Isolates from selective agar were initially identified using biochemical tests and confirmed using genus-specific primers and 16S ribosomal RNA (16S rRNA) sequencing. Random amplified polymorphic DNA (RAPD) PCR was used to type both Pseudomonas and Vibrio; the latter was further typed using a biochemical fingerprinting method (PhP-RV plates). We observed low species diversity with strains comprising Vibrio ichthyoenteri/Vibrio scophthalmi, Vibrio crassostreae/Vibrio splendidus, Aliivibrio finisterrensis, Photobacterium phosphoreum and Pseudomonas fragi. Out of 340 Vibrio isolates, 238 (70 %) belonged to 21 clonal types and were found predominantly during summer when water temperatures reached 15 to 21 °C. Of these, the four major clonal types were found in multiple samples (70 %). P. fragi, on the other hand, was only found during the colder water temperatures and belonged to 18 clonal types. The presence of both groups of bacteria and their clonal types were independent of the fish diets used, suggesting that the water temperature was the main factor of the prevalence and persistence of these bacteria in the gut of Atlantic salmon.

  16. Natural infection of Atlantic salmon (Salmo salar L.) with salmonid alphavirus 3 generates numerous viral deletion mutants.

    Science.gov (United States)

    Petterson, Elin; Stormoen, Marit; Evensen, Øystein; Mikalsen, Aase B; Haugland, Øyvind

    2013-09-01

    Salmon pancreas disease virus (SPDV) also referred to as salmonid alphavirus (SAV) is a virus causing pancreas disease in Atlantic salmon (Salmo salar L.) and rainbow trout (Oncorhynchus mykiss). Although the virus causes an economically important disease, relatively few full-length genome sequences of SAV strains are currently available. Here, we report full-length genome sequences of nine SAV3 strains from sites farming Atlantic salmon geographically spread along the Norwegian coastline. The virus genomes were sequenced directly from infected heart tissue, to avoid culture selection bias. Sequence analysis confirmed a high level of sequence identity within SAV3 strains, with a mean nucleotide diversity of 0.11 %. Sequence divergence was highest in 6K and E2, while lowest in the capsid protein and the non-structural proteins (nsP4 and nsP2). This study reports for the first time that numerous defective viruses containing genome deletions are generated during natural infection with SAV. Deletions occurred in all virus strains and were not distributed randomly throughout the genome but instead tended to aggregate in certain areas. We suggest imprecise homologous recombination as an explanation for generation of defective viruses with genome deletions. The presence of such viruses, provides a possible explanation for the difficulties in isolating SAV in cell culture. Primary virus isolation was successfully achieved for only two of eight strains, despite extensive attempts using three different cell lines. Both SAV isolates were easily propagated further and concomitant viral deletion mutants present in clinically infected heart tissue were maintained following serial passage in CHH-1 cells.

  17. Delousing efficiency of farmed ballan wrasse (Labrus bergylta) against Lepeophtheirus salmonis infecting Atlantic salmon (Salmo salar) post-smolts.

    Science.gov (United States)

    Leclercq, Eric; Davie, Andrew; Migaud, Hervé

    2014-08-01

    Cleaner-fish (wrasse, Labridae) are increasingly deployed within the Atlantic salmon (Salmo salar L.) industry as a biological control against sea-lice (Lepeophtheirus salmonis Krøyer). Two tank-based trials were performed to test the effect of farmed ballan wrasse (Labrus bergylta Ascanius) body mass and supplementary feeding on the delousing of Atlantic salmon post-smolts with an initial infection level of ∼12 lice salmon(-1) and a ∼5% wrasse:salmon ratio. Sea-louse levels below 0.5 lice salmon(-1) were obtained within 84 h, and preferential preying upon larger motile stages was found. The wrasse body mass and the availability of fresh, opened blue mussels (Mytilus edulis L.) did not significantly affect delousing efficiency. The functional predator response was linear, showing no minimum prey density threshold for sea-louse foraging and no satiation plateau, in spite of the high consumption rates measured. Sea-louse infection levels declined following a one-phase exponential decay model, with a standardised decline time constant of 0.8-1.3% h(-1) for each wrasse stocked per 100 salmon. Farmed ballan wrasse are confirmed as highly effective therapeutic and preventive biological controls against sea-lice. The study supports the current minimum hatchery size target (10 mm total length) and the use of supplementary feeding to sustain the wrasse stocks in operation. The functional predator response and the standardised decline time constant of sea-louse abundance are proposed as useful indicators of delousing efficiency. © 2013 Society of Chemical Industry.

  18. Contaminant levels in Norwegian farmed Atlantic salmon (Salmo salar) in the 13-year period from 1999 to 2011.

    Science.gov (United States)

    Nøstbakken, Ole Jakob; Hove, Helge T; Duinker, Arne; Lundebye, Anne-Katrine; Berntssen, Marc H G; Hannisdal, Rita; Lunestad, Bjørn Tore; Maage, Amund; Madsen, Lise; Torstensen, Bente E; Julshamn, Kåre

    2015-01-01

    Environmental pollutants such as dioxins and PCBs, heavy metals, and organochlorine pesticides are a global threat to food safety. In particular, the aquatic biota can bioaccumulate many of these contaminants potentially making seafood of concern for chronic exposure to humans. The main objective was to evaluate trends of contaminant levels in Norwegian farmed Atlantic salmon in light of the derived tolerable intakes. Through an EU-instigated surveillance programme, the Norwegian Food Safety Authority (NFSA) has between 1999 and 2011 collected more than 2300 samples of Norwegian farmed Atlantic salmon (Salmo salar) for contaminant analyses. The fillets of these fish were homogenised and analysed for dioxins, PCBs, heavy metals and organochlorine pesticides. The levels of the contaminants mercury, arsenic, dioxins, dioxin-like PCBs and DDT in Norwegian farmed salmon fillet have decreased during our period of analyses. The levels of cadmium, lead and several organochlorine pesticides were too close to the limit of quantification to calculate time trends. For PCB6 and quantifiable amounts of pesticides, except DDT, stable levels were observed. The contaminant levels in Norwegian farmed salmon have generally decreased between 1999 and 2011. Excluding other dietary sources, the levels of dioxins and dioxin-like PCBs in 2011 allowed consumption of up to 1.3kg salmon per week to reach the tolerable weekly intake. The group of contaminants which was the limiting factor for safe consumption of Norwegian farmed salmon, based on currently established TWI values, is the sum of dioxins and dioxin-like PCBs. Copyright © 2014. Published by Elsevier Ltd.

  19. Social hierarchies, growth and brain serotonin metabolism in Atlantic salmon (Salmo salar) kept under commercial rearing conditions.

    Science.gov (United States)

    Cubitt, K Fiona; Winberg, Svante; Huntingford, Felicity A; Kadri, Sunil; Crampton, Vivian O; Overli, Oyvind

    2008-07-05

    Monitoring social interactions between individuals in large, high-density groups poses several challenges. Here we demonstrate that relative concentrations of serotonin (5-Hydroxytryptamine, 5-HT) and its principal catabolite 5-Hydroxyindoleacetic acid (5-HIAA) in brain tissue of individual fish reflect social organisation in large groups of farmed Atlantic salmon. In the central nervous system of vertebrates, the monoamine neurotransmitter/neuromodulator 5-HT is critical for maintaining adaptive physiological, cognitive and emotional processes. In both teleost fish and mammals it has previously been shown that social interactions in small groups lead to elevated 5-HT release and/or metabolism in subordinate individuals, as indicated by the 5-HIAA/5-HT concentration ratio. In the current study, evidence is presented of non-linear dominance hierarchies in farmed Atlantic salmon (Salmo salar) kept at high rearing densities. The physiological effect of these hierarchies was decreased when food resources were abundant, although some subordinate fish still showed altered brain serotonergic activity and failed to grow even feed was available in excess. The largest effect of decreased feed rations was seen in fish of intermediate size, where competition appeared to increase with reduced access to feed. The largest individuals in each rearing unit showed low 5-HIAA/5-HT ratios independent of feeding regime. A novel observation, with respect to previous studies, was that elevated brain 5-HIAA/5-HT ratios resulted from decreased 5-HT concentrations rather than elevated 5-HIAA in small fish. Thus, in light of the serotonin deficit hypothesis of depression, it cannot be excluded that social stress is important for animal welfare even in large, relatively homogenous groups of animals reared in captivity.

  20. Metabolic effects of amoebic gill disease (AGD) and chloramine-T exposure in seawater-acclimated Atlantic salmon Salmo salar.

    Science.gov (United States)

    Leef, M J; Harris, J O; Powell, M D

    2007-10-31

    Our aim was to determine possible metabolic effects amoebic gill disease (AGD) on Atlantic salmon Salmo salar. Standard (R(S)) and routine (R(ROU)) metabolic rates were evaluated by continually measuring oxygen consumption in 2 independent tanks of fish (18.69 +/- 1.01 kg m(-3), mean +/- SE). Active metabolic rate (R(ACT)) and metabolic scope (R(ACT) - R(S)) were assessed using a chasing protocol and determined at 3 time periods: (1) pre-infection, (2) 3 d post-infection, and (3) 2 d post-treatment. On Day 3 of the study, the fish were infected with amoebae isolated from the gills of AGD-affected salmon (2300 cells l(-1)). No significant elevations in R(ACT) or metabolic scope were detected 3 d post-infection and 2 d post-treatment; however, significant elevations in R(S) and R(ROU) were detected 3 d post-infection and 2 d post-treatment. Assessment of R(ROU) data, especially for the light period, also indicated a rise in oxygen consumption rate over the course of the experiment. Treatment of AGD-affected Atlantic salmon with chloramine-T (CL-T) appeared to briefly mitigate the rise in R(S), as there was a 30% drop (though non-significant) in R(S) following treatment. Despite this, R(S) continued the upward trend 1 d following treatment. These results suggest that over the course of AGD development, R(S) in Atlantic salmon increases. Therefore, considering the physical conditions which constrain R(ACT), we expect that metabolic scope would become compromised in fish more heavily affected with AGD. Treatment with CL-T shows promise for mitigating the respiratory effects of AGD and potentially minimising the loss of metabolic scope.

  1. Effects of algal-produced neurotoxins on metabolic activity in telencephalon, optic tectum and cerebellum of Atlantic salmon (Salmo salar)

    Energy Technology Data Exchange (ETDEWEB)

    Bakke, Marit Jorgensen [Department of Pharmacology and Toxicology, Norwegian School of Veterinary Science, PO Box 8146 Dep., N-0033 Oslo (Norway); Horsberg, Tor Einar [Department of Pharmacology and Toxicology, Norwegian School of Veterinary Science, PO Box 8146 Dep., N-0033 Oslo (Norway)], E-mail: tor.e.horsberg@veths.no

    2007-11-30

    Neurotoxins from algal blooms have been reported to cause mortality in a variety of species, including sea birds, sea mammals and fish. Farmed fish cannot escape harmful algal blooms and their potential toxins, thus they are more vulnerable for exposure than wild stocks. Sublethal doses of the toxins are likely to affect fish behaviour and may impair cognitive abilities. In the present study, changes in the metabolic activity in different parts of the Atlantic salmon (Salmo salar) brain involved in central integration and cognition were investigated after exposure to sublethal doses of three algal-produced neurotoxins; saxitoxin (STX), brevetoxin (BTX) and domoic acid (DA). Fish were randomly selected to four groups for i.p. injection of saline (control) or one of the neurotoxins STX (10 {mu}g STX/kg bw), BTX (68 {mu}g BTX/kg bw) or DA (6 mg DA/kg bw). In addition, {sup 14}C-2-deoxyglucose was i.m. injected to measure brain metabolic activity by autoradiography. The three regions investigated were telencephalon (Tel), optic tectum (OT) and cerebellum (Ce). There were no differences in the metabolic activity after STX and BTX exposure compared to the control in these regions. However, a clear increase was observed after DA exposure. When the subregions with the highest metabolic rate were pseudocoloured in the three brain regions, the three toxins caused distinct differences in the respective patterns of metabolic activation. Fish exposed to STX displayed similar patterns as the control fish, whereas fish exposed to BTX and DA showed highest metabolic activity in subregions different from the control group. All three neurotoxins affected subregions that are believed to be involved in cognitive abilities in fish.

  2. Multi-level assessment of chronic toxicity of estuarine sediments with the amphipod Gammarus locusta: II. Organism and population-level endpoints.

    Science.gov (United States)

    Costa, Filipe O; Neuparth, Teresa; Correia, Ana D; Costa, Maria Helena

    2005-07-01

    This study aimed to test the performance of the amphipod Gammarus locusta (L.) in chronic sediment toxicity tests. It constitutes part of a multi-level assessment of chronic toxicity of estuarine sediments, integrating organism and population-level endpoints with biochemical markers responses. Here we account for organism and population-level effects, while biomarker responses were reported in a companion article. Five moderately contaminated sediments from Sado and Tagus estuaries were tested, comprising 3 muddy and 2 sandy sediments. These sediments either did not show acute toxicity or were diluted with control sediment as much as required to remove acute toxicity. Subsequent chronic tests consisted of 28-day exposures with survival, individual growth and reproductive traits as endpoints. Two of the muddy sediments induced higher growth rates in the amphipods, and improved reproductive traits. This was understood to be a consequence of the amount of organic matter in the sediment, which was nutritionally beneficial to the amphipods, while concurrently decreasing contaminant bioavailability. Biomarker responses did not reveal toxicant-induced stress in amphipods exposed to these sediments. One of the sandy sediments was acutely toxic at 50% dilution, but in contrast stimulated amphipod growth when diluted 75%. This was presumed to be an indication of a hormetic response. Finally the two remaining contaminated sediments showed pronounced chronic toxicity, affecting survival and reproduction. The sex ratio of survivors was highly biased towards females, and offspring production was severely impaired. The particulars of the responses of this amphipod were examined, as well as strengths versus limitations of the sediment test. This study illustrates the utility of this chronic test for toxicity assessment of contaminated estuarine sediments, with potential application all along Atlantic Europe.

  3. The Relationship Between Population-Level Exposure to Alcohol Advertising on Television and Brand-Specific Consumption Among Underage Youth in the US

    Science.gov (United States)

    Ross, Craig S.; Maple, Emily; Siegel, Michael; DeJong, William; Naimi, Timothy S.; Padon, Alisa A.; Borzekowski, Dina L.G.; Jernigan, David H.

    2015-01-01

    Aims: We investigated the population-level relationship between exposure to brand-specific advertising and brand-specific alcohol use among US youth. Methods: We conducted an internet survey of a national sample of 1031 youth, ages 13–20, who had consumed alcohol in the past 30 days. We ascertained all of the alcohol brands respondents consumed in the past 30 days, as well as which of 20 popular television shows they had viewed during that time period. Using a negative binomial regression model, we examined the relationship between aggregated brand-specific exposure to alcohol advertising on the 20 television shows [ad stock, measured in gross rating points (GRPs)] and youth brand-consumption prevalence, while controlling for the average price and overall market share of each brand. Results: Brands with advertising exposure on the 20 television shows had a consumption prevalence about four times higher than brands not advertising on those shows. Brand-level advertising elasticity of demand varied by exposure level, with higher elasticity in the lower exposure range. The estimated advertising elasticity of 0.63 in the lower exposure range indicates that for each 1% increase in advertising exposure, a brand's youth consumption prevalence increases by 0.63%. Conclusions: At the population level, underage youths' exposure to brand-specific advertising was a significant predictor of the consumption prevalence of that brand, independent of each brand's price and overall market share. The non-linearity of the observed relationship suggests that youth advertising exposure may need to be lowered substantially in order to decrease consumption of the most heavily advertised brands. PMID:25754127

  4. Enhanced transcriptomic responses in the Pacific salmon louse Lepeophtheirus salmonis oncorhynchi to the non-native Atlantic Salmon Salmo salar suggests increased parasite fitness.

    Science.gov (United States)

    Braden, Laura M; Sutherland, Ben J G; Koop, Ben F; Jones, Simon R M

    2017-01-30

    Outcomes of infections with the salmon louse Lepeophtheirus salmonis vary considerably among its natural hosts (Salmo, Oncorhynchus spp.). Host-parasite interactions range from weak to strong host responses accompanied by high to low parasite abundances, respectively. Parasite behavioral studies indicate that the louse prefers the host Atlantic Salmon (Salmo salar), which is characterized by a weak immune response, and that this results in enhanced parasite reproduction and growth rates. Furthermore, parasite-derived immunosuppressive molecules (e.g., proteases) have been detected at higher amounts in response to the mucus of Atlantic Salmon relative to Coho Salmon (Oncorhynchus kisutch). However, the host-specific responses of the salmon louse have not been well characterized in either of the genetically distinct sub-species that occur in the Atlantic and Pacific Oceans. We assessed and compared the transcriptomic feeding response of the Pacific salmon louse (L. salmonis oncorhynchi,) while parasitizing the highly susceptible Atlantic Salmon and Sockeye Salmon (Oncorhynchus nerka) or the more resistant Coho Salmon (Oncorhynchus kisutch) using a 38 K oligonucleotide microarray. The response of the louse was enhanced both in the number of overexpressed genes and in the magnitude of expression while feeding on the non-native Atlantic Salmon, compared to either Coho or Sockeye Salmon. For example, putative virulence factors (e.g., cathepsin L, trypsin, carboxypeptidase B), metabolic enzymes (e.g., cytochrome B, cytochrome C), protein synthesis enzymes (e.g., ribosomal protein P2, 60S ribosomal protein L7), and reproduction-related genes (e.g., estrogen sulfotransferase) were overexpressed in Atlantic-fed lice, indicating heightened parasite fitness with this host species. In contrast, responses in Coho- or Sockeye-fed lice were more similar to those of parasites deprived of a host. To test for host acclimation by the parasite, we performed a reciprocal host transfer

  5. Individual and population level impacts of illicit drug use, sexual risk behaviours on sexually transmitted infections among young Aboriginal and Torres Strait Islander people: results from the GOANNA survey

    Directory of Open Access Journals (Sweden)

    Handan Wand

    2016-07-01

    Full Text Available Abstract Background Sexually transmitted infections (STIs have been increasing among Australian Indigenous young people for over two decades. Little is known about the association between alcohol and other drug use and sexual risk behaviours and diagnosis of STIs among this population. Methods A cross-sectional, community based self-administered survey was conducted among young Aboriginal people aged 16–29 years of age. Questionnaires included socio-demographic characteristics, knowledge, sexual risk behaviours alcohol and other drug use and health service access including self-reported history of diagnosis with a STI. Logistic regression models and population attributable risks were used to assess individual and population level impacts of illicit drug use on high risk sexual behaviours and ever reported diagnosis of an STI. Results Of the 2877 participants, 2320 (81 % identified as sexually active and were included in this study. More than 50 % of the study population reported that they had used at least one illicit drug in past year. Cannabis, ecstasy and methamphetamines were the three most commonly used illicit drugs in the past year. The prevalence of self-reported STI diagnosis was 25 %. Compared with people who did not report using illicit drugs, risky alcohol use and sexual behaviours including inconsistent condom use, multiple sexual partners in the past year and sex with casual partners were all significantly higher among illicit drug users. In adjusted analysis, participants who reported using illicit drugs were significantly more likely to engage in sexual risk behaviours and to ever have been diagnosed with an STI. Adjusted Odds Ratios ranged from 1.86 to 3.00 (males and from 1.43 to 2.46 (females. At the population level, more than 70 % of the STI diagnoses were attributed to illicit drug-use and sexual risk behaviours for males and females. Conclusion Illicit drug use in this population is relatively high compared to other

  6. Effects of crowding on blood constituents and flesh quality variables in Atlantic salmon (Salmo salar L.) Efecto del confinamiento sobre las variables sanguíneas y calidad de carne de Salmón Atlántico (Salmo salar L.)

    OpenAIRE

    MC Gatica; GE Monti; TG Knowles; CB Gallo

    2010-01-01

    The effects of anaesthesia (as a control treatment) and controlled crowding, with its concomitant low oxygen level, on harvest size salmon (Salmo salar) were compared in terms of blood constituents and flesh quality variables, at 0, 1, 4, 7 and 10 days post-mortem. Fish were held in tanks in triplicate and were sampled after anaesthetizing with AQUI-S® and after crowding for one hour. Eighteen fish from each treatment were stunned, blood sampled from the posterior aorta and the fish bled by g...

  7. Combined effects of gamma irradiation and cadmium on cellular and population-level endpoints of the micro-alga Pseudokirchneriella subcapitata

    Energy Technology Data Exchange (ETDEWEB)

    Bradshaw, C. [Stockholm University (Sweden); Abdul Meseh, D.; Alasawi, H.; Qiang, M.; Nascimento, F. [Dept of Ecology, Environment and Plant Sciences (Sweden)

    2014-07-01

    A major challenge in evaluating the risks of radiation to organisms is that radioactive substances often co-occur with other contaminants in the environment. The combined effects of multiple contaminants is poorly understood, particularly where radiation is involved, but mixture toxicity can give rise to synergistic, antagonistic or additive effects. The challenge of understanding mixture toxicity in a radiation context is the focus of one of the work packages of the STAR EU Network of Excellence in Radioecology, of which this study is a part. This paper presents results from an experiment where the green micro-alga Pseudokirchneriella subcapitata was exposed to both acute external gamma irradiation and the toxic metal cadmium (Cd) (over 72 hours); the experiment had a fully factorial design with 4 gamma doses and 4 Cd concentrations. The endpoints measured were chosen to reflect subcellular, cellular and population-level effects: antioxidant enzyme expression; membrane damage; protein, vitamin and pigment content of the cells; individual cell biomass and growth; population growth (biomass per ml and cells per ml). Preliminary results suggest effects of both Cd and gamma on some of the cellular and subcellular endpoints such as thiamine (vitamin B1) and chlorophyll concentrations in the cells, and individual cell biomass. In some cases interactive effects of the combined Cd and gamma treatments were seen, and these appeared to be dose level dependent. This lack of a consistent pattern of interactive mixture toxicity effects across the endpoints measured means that such effects would be very hard to predict in a risk assessment context. The lack of measurable effects at the population level was probably due to the short experimental duration (72 hours). Other experiments in our research group on the same micro-alga species that have looked at longer term effects (weeks) have shown that effects may not manifest themselves until at least a week after an acute gamma

  8. A critical life stage of the Atlantic salmon Salmo salar: behaviour and survival during the smolt and initial post-smolt migration.

    Science.gov (United States)

    Thorstad, E B; Whoriskey, F; Uglem, I; Moore, A; Rikardsen, A H; Finstad, B

    2012-07-01

    The anadromous life cycle of Atlantic salmon Salmo salar involves long migrations to novel environments and challenging physiological transformations when moving between salt-free and salt-rich waters. In this article, (1) environmental factors affecting the migration behaviour and survival of smolts and post-smolts during the river, estuarine and early marine phases, (2) how behavioural patterns are linked to survival and (3) how anthropogenic factors affect migration and survival are synthesized and reviewed based on published literature. The timing of the smolt migration is important in determining marine survival. The timing varies among rivers, most likely as a consequence of local adaptations, to ensure sea entry during optimal periods. Smolts and post-smolts swim actively and fast during migration, but in areas with strong currents, their own movements may be overridden by current-induced transport. Progression rates during the early marine migration vary between 0.4 and 3.0 body lengths s(-1) relative to the ground. Reported mortality is 0.3-7.0% (median 2.3) km(-1) during downriver migration, 0.6-36% (median 6.0) km(-1) in estuaries and 0.3-3.4% (median 1.4) km(-1) in coastal areas. Estuaries and river mouths are the sites of the highest mortalities, with predation being a common cause. The mortality rates varied more among studies in estuaries than in rivers and marine areas, which probably reflects the huge variation among estuaries in their characteristics. Behaviour and survival during migration may also be affected by pollution, fish farming, sea lice Lepeophtheirus salmonis, hydropower development and other anthropogenic activities that may be directly lethal, delay migration or have indirect effects by inhibiting migration. Total mortality reported during early marine migration (up to 5-230 km from the river mouths) in the studies available to date varies between 8 and 71%. Hence, the early marine migration is a life stage with high mortalities, due

  9. Chronic dietary mercury exposure causes oxidative stress, brain lesions, and altered behaviour in Atlantic salmon (Salmo salar) parr

    Energy Technology Data Exchange (ETDEWEB)

    Berntssen, Marc H.G.; Aatland, Aase; Handy, Richard D

    2003-10-08

    Atlantic salmon (Salmo salar L.) parr were fed for 4 months on fish meal based diets supplemented with mercuric chloride (0, 10, or 100 mg Hg kg{sup -1} DW) or methylmercury chloride (0, 5, or 10 mg Hg kg{sup -1} DW) to assess the effects of inorganic (Hg) and organic dietary mercury on brain lipid peroxidation and neurotoxicity. Lipid peroxidative products, endogenous anti oxidant enzymes, brain histopathology, and overall behaviour were measured. Methylmercury accumulated significantly in the brain of fish fed 5 or 10 mg kg{sup -1} by the end of the experiment, and inorganic mercury accumulated significantly in the brain only at 100 mg kg{sup -1} exposure levels. No mortality or growth reduction was observed in any of the exposure groups. Fish fed 5 mg kg{sup -1} methylmercury had a significant increase (2-fold) in the antioxidant enzyme super oxide dismutase (SOD) in the brain. At dietary levels of 10 mg kg{sup -1} methylmercury, a significant increase (7-fold) was observed in lipid peroxidative products (thiobarbituric acid reactive substances, TBARS) and a subsequently decrease (1.5-fold) in anti oxidant enzyme activity (SOD and glutathione peroxidase, GSH-Px). Fish fed 10 mg kg{sup -1} methylmercury also had pathological damage (vacoulation and necrosis), significantly reduced neural enzyme activity (5-fold reduced monoamine oxidase, MAO, activity), and reduced overall post-feeding activity behaviour. Pathological injury started in the brain stem and became more widespread in other areas of the brain at higher exposure levels. Fish fed 100 mg Hg kg{sup -1} inorganic mercury had significant reduced neural MAO activity and pathological changes (astrocyte proliferation) in the brain, however, neural SOD and GSH-Px enzyme activity, lipid peroxidative products (TBARS), and post feeding behaviour did not differ from controls. Compared with other organs, the brain is particular susceptible for dietary methylmercury induced lipid peroxidative stress at relative low

  10. Annotated Expressed Sequence Tags (ESTs from pre-smolt Atlantic salmon (Salmo salar in a searchable data resource

    Directory of Open Access Journals (Sweden)

    Ruden Torgeir A

    2007-07-01

    Full Text Available Abstract Background To identify as many different transcripts/genes in the Atlantic salmon genome as possible, it is crucial to acquire good cDNA libraries from different tissues and developmental stages, their relevant sequences (ESTs or full length sequences and attempt to predict function. Such libraries allow identification of a large number of different transcripts and can provide valuable information on genes expressed in a particular tissue at a specific developmental stage. This data is important in constructing a microarray chip, identifying SNPs in coding regions, and for future identification of genes in the whole genome sequence. An important factor that determines the usefulness of generated data for biologists is efficient data access. Public searchable databases play a crucial role in providing such service. Description Twenty-three Atlantic salmon cDNA libraries were constructed from 15 tissues, yielding nearly 155,000 clones. From these libraries 58,109 ESTs were generated, of which 57,212 were used for contig assembly. Following deletion of mitochondrial sequences 55,118 EST sequences were submitted to GenBank. In all, 20,019 unique sequences, consisting of 6,424 contigs and 13,595 singlets, were generated. The Norwegian Salmon Genome Project Database has been constructed and annotation performed by the annotation transfer approach. Annotation was successful for 50.3% (10,075 of the sequences and 6,113 sequences (30.5% were annotated with Gene Ontology terms for molecular function, biological process and cellular component. Conclusion We describe the construction of cDNA libraries from juvenile/pre-smolt Atlantic salmon (Salmo salar, EST sequencing, clustering, and annotation by assigning putative function to the transcripts. These sequences represents 97% of all sequences submitted to GenBank from the pre-smoltification stage. The data has been grouped into datasets according to its source and type of annotation. Various data

  11. Lack of arterial PO2 downregulation in Atlantic salmon (Salmo salar L.) during long-term normoxia and hyperoxia.

    Science.gov (United States)

    Kristensen, T; Rosseland, B O; Kiessling, A; Djordevic, B; Massabau, J C

    2010-12-01

    Regulation of arterial partial pressure of O2 (PaO2) in Atlantic salmon (Salmo salar) was investigated during resting conditions in normoxic and hyperoxic water. Dorsal aorta cannulated adult Atlantic salmon (1.2-1.6 kg, n=8) were exposed to 2 week sequential periods of normoxia [16.7±1.1 kPa (mean±SD)] and hyperoxia (34.1±4.9 kPa) in individual tanks containing seawater (33.7±0.2 ppt) at stable temperature conditions (8.7±0.7°C) and a light regime of L:D=12:12. Tank design and sampling procedures were optimized to provide suitable shelter and current for the fish, and to allow repeated, undisturbed sampling of blood from free-swimming fish. Fish were sampled regularly through the experimental period. PwO2, PaO2, blood ion composition (Na+, K+, Cl-), acid-base status (pH, PCO2, HCO3-), haematocrit and glucose were measured. The most frequently observed PaO2 values were in the range of 60-80% of PwO2, both during normoxia and hyperoxia, and PaO2 values were significantly lower during normoxia than during hyperoxia. Blood pH, PCO2 and HCO3- were significantly elevated during hyperoxia, while, Na+, Cl- and Hct were significantly lower. K+ and glucose showed no significant differences. This study demonstrates a lack PaO2 regulation in Atlantic salmon to low partial pressures, in contrast to previous reports for many aquatic gill breathing animals. Both during normoxia and hyperoxia, PaO2 reflects PwO2, and alterations in external PO2 consequently result in proportional arterial PO2 changes. Physiological adaptation to hyperoxia, as illustrated by changes in several blood parameters, does not include down-regulation of PaO2 in Atlantic salmon. The lack of PaO2 regulation may make Atlantic salmon vulnerable to the oxidative stress caused by increased free radical formation in hyperoxic conditions.

  12. Hepatic transcriptional responses in Atlantic salmon (Salmo salar) exposed to gamma radiation and depleted uranium singly and in combination

    Energy Technology Data Exchange (ETDEWEB)

    Song, You, E-mail: yso@niva.no [Norwegian University of Life Sciences (NMBU), Faculty of Environmental Science and Technology, Department of Environmental Sciences (IMV), Centre for Environmental Radioactivity - CERAD, P.O. Box 5003, N-1432 Ås (Norway); Norwegian Institute for Water Research (NIVA), Gaustadalléen 21, N-0349 Oslo (Norway); Salbu, Brit; Teien, Hans-Christian [Norwegian University of Life Sciences (NMBU), Faculty of Environmental Science and Technology, Department of Environmental Sciences (IMV), Centre for Environmental Radioactivity - CERAD, P.O. Box 5003, N-1432 Ås (Norway); Evensen, Øystein [Norwegian University of Life Sciences (NMBU), Department of Basic Sciences and Aquatic Medicine, P.O. Box 8146 Dep., N-0033 Oslo (Norway); Lind, Ole Christian [Norwegian University of Life Sciences (NMBU), Faculty of Environmental Science and Technology, Department of Environmental Sciences (IMV), Centre for Environmental Radioactivity - CERAD, P.O. Box 5003, N-1432 Ås (Norway); Rosseland, Bjørn Olav [Norwegian University of Life Sciences (NMBU), Faculty of Environmental Science and Technology, Department of Environmental Sciences (IMV), Centre for Environmental Radioactivity - CERAD, P.O. Box 5003, N-1432 Ås (Norway); Norwegian University of Life Sciences (NMBU), Department of Ecology and Natural Resource Management (INA), P.O. Box 5003, N-1432 Ås (Norway); and others

    2016-08-15

    Radionuclides are a special group of substances posing both radiological and chemical hazards to organisms. As a preliminary approach to understand the combined effects of radionuclides, exposure studies were designed using gamma radiation (Gamma) and depleted uranium (DU) as stressors, representing a combination of radiological (radiation) and chemical (metal) exposure. Juvenile Atlantic salmon (Salmo salar) were exposed to 70 mGy external Gamma dose delivered over the first 5 h of a 48 h period (14 mGy/h), 0.25 mg/L DU were exposed continuously for 48 h and the combination of the two stressors (Combi). Water and tissue concentrations of U were determined to assess the exposure quality and DU bioaccumulation. Hepatic gene expression changes were determined using microarrays in combination with quantitative real-time reverse transcription polymerase chain reaction (qPCR). Effects at the higher physiological levels were determined as plasma glucose (general stress) and hepatic histological changes. The results show that bioaccumulation of DU was observed after both single DU and the combined exposure. Global transcriptional analysis showed that 3122, 2303 and 3460 differentially expressed genes (DEGs) were significantly regulated by exposure to gamma, DU and Combi, respectively. Among these, 349 genes were commonly regulated by all treatments, while the majority was found to be treatment-specific. Functional analysis of DEGs revealed that the stressors displayed similar mode of action (MoA) across treatments such as induction of oxidative stress, DNA damage and disturbance of oxidative phosphorylation, but also stressor-specific mechanisms such as cellular stress and injury, metabolic disorder, programmed cell death, immune response. No changes in plasma glucose level as an indicator of general stress and hepatic histological changes were observed. Although no direct linkage was successfully established between molecular responses and adverse effects at the organism

  13. A comprehensive assessment of mercury exposure in penguin populations throughout the Southern Hemisphere: Using trophic calculations to identify sources of population-level variation.

    Science.gov (United States)

    Brasso, Rebecka L; Chiaradia, André; Polito, Michael J; Raya Rey, Andrea; Emslie, Steven D

    2015-08-15

    The wide geographic distribution of penguins (Order Sphenisciformes) throughout the Southern Hemisphere provided a unique opportunity to use a single taxonomic group as biomonitors of mercury among geographically distinct marine ecosystems. Mercury concentrations were compared among ten species of penguins representing 26 geographically distinct breeding populations. Mercury concentrations were relatively low (⩽2.00ppm) in feathers from 18/26 populations considered. Population-level differences in trophic level explained variation in mercury concentrations among Little, King, and Gentoo penguin populations. However, Southern Rockhopper and Magellanic penguins breeding on Staten Island, Tierra del Fuego, had the highest mercury concentrations relative to their conspecifics despite foraging at a lower trophic level. The concurrent use of stable isotope and mercury data allowed us to document penguin populations at the greatest risk of exposure to harmful concentrations of mercury as a result of foraging at a high trophic level or in geographic 'hot spots' of mercury availability. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. A review of the validity and reliability of alcohol retail sales data for monitoring population levels of alcohol consumption: a Scottish perspective.

    Science.gov (United States)

    Robinson, Mark; Thorpe, Rachel; Beeston, Clare; McCartney, Gerry

    2013-01-01

    To assess the validity and reliability of using alcohol retail sales data to measure and monitor population levels of alcohol consumption. Potential sources of bias that could lead to under- or overestimation of population alcohol consumption based on alcohol retail sales data were identified and, where possible, quantified. This enabled an assessment of the potential impact of each bias on alcohol consumption estimates in Scotland. Overall, considering all the possible sources of overestimation and underestimation, and taking into account the potential for sampling variability to impact on the results, the range of uncertainty of consumption during 2010 was from an overestimate of 0.3 l to an underestimate of 2.4 l of pure alcohol per adult. This excludes the impacts of alcohol stockpiling and alcohol sold through outlets not included in the sampling frame. On balance, there is therefore far greater scope for alcohol retail sales data to be underestimating per adult alcohol consumption in Scotland than there is for overestimation. Alcohol retail sales data offer a robust source of data for monitoring per adult alcohol consumption in Scotland. Consideration of the sources of bias and a comprehensive understanding of data collection methods are essential for using sales data to monitor trends in alcohol consumption.

  15. Socio-behavioural aspects in the prevention and control of dental caries and periodontal diseases at an individual and population level.

    Science.gov (United States)

    Sälzer, Sonja; Alkilzy, Mohammad; Slot, Dagmar E; Dörfer, Christof E; Schmoeckel, Julian; Splieth, Christian H

    2017-03-01

    Aim was to systematically review behavioural aspects in the prevention and control of dental caries and periodontal diseases at individual and population level. With regard to caries, MEDLINE/PubMed was searched on three subheadings focusing on early childhood, proximal and root caries. For periodontal diseases, a meta-review on systematic reviews was performed; thus, the search strategy included specific interventions to change behaviour in order to perform a meta-review on systematic reviews. After extraction of data and conclusions, the potential risk of bias was estimated and the emerging evidence was graded. Regarding early childhood, proximal and root caries, 28, 6 and 0 papers, respectively, could be included, which predominantly reported on cohort studies. Regarding periodontal diseases, five systematic reviews were included. High evidence of mostly high magnitude was retrieved for behavioural interventions in early childhood caries (ECC), weak evidence for a small effect in proximal caries and an unclear effect of specific informational/motivational programmes on prevention of periodontal diseases and no evidence of root caries. Early childhood caries can be successfully prevented by population-based preventive programmes via aiming at the change in behaviour. The effect of individual specific motivational/informational interventions has not yet been clearly demonstrated neither for the prevention of caries nor for periodontal diseases. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  16. Evaluación de la alimentación de Salmo salar en piscicultura, utilizando dispensadores automáticos

    Directory of Open Access Journals (Sweden)

    A. Mardones

    2013-09-01

    Full Text Available El cultivo de salmones, específicamente Salmo salar es una industria que genera aspectos básicos y aplicados destinado a su producción intensiva. En este contexto, el presente estudio evaluó el crecimiento de salmones en cultivo bajo tres condiciones, alimentador manual con alimentación diurna, con alimentación nocturna, y día y noche, y un grupo control con alimentación manual a saciedad. Se encontró menor crecimiento en el grupo control respecto a los tres grupos alimentados con alimentador artificial. Estos resultados concuerdan con las descripciones de la literatura para el hemisferio norte.

  17. Net ground speed of downstream migrating radio-tagged Atlantic salmon ( Salmo salar L.) and brown trout ( Salmo trutta L.) smolts in relation to environmental factors

    DEFF Research Database (Denmark)

    Aarestrup, Kim; Nielsen, C.; Koed, Anders

    2002-01-01

    tagged and released in the Danish River Lilleaa. The downstream migration of the different groups of fish was monitored by manual tracking and by three automatic listening stations. The downstream migration of radio tagged smolts of both species occurred concurrently with their untagged counterparts......The downstream migration of Atlantic salmon (Salmo salar L.) and sea trout smolt (S. trutta L.) was investigated using radio telemetry in the spring of 1999 and 2000. Forty wild sea trout smolts, 20 F1 sea trout smolts, 20 hatchery salmon smolts and 20 salmon smolts from river stockings were radio....... The diel migration pattern of the radio tagged smolts was predominantly nocturnal in both species. Wild sea trout smolt migrated significantly faster than both the F1 trout and the introduced salmon. There was no correlation between net ground speed, gill Na+, K+-ATPase activity or fish length in any...

  18. Histochemical demonstration of mercury in the olfactory system of salmon (Salmo salar L.) following treatments with dietary methylmercuric chloride and dissolved mercuric chloride

    DEFF Research Database (Denmark)

    Baatrup, E; Døving, K B

    1991-01-01

    in the olfactory rosettes and their nerves. Tissue sections from the rosettes and olfactory nerves were subjected to autometallographic silver enhancement, thereby rendering mercury deposits visible for light and electron microscopy. Microscopic analysis demonstrated an intense and comprehensive Hg deposition......The deposition of organic and inorganic mercury compounds was studied histochemically in the salmon (Salmo salar L.) olfactory system. One group of salmon was given fodder pellets containing methylmercuric chloride (CH3HgCl, 99 micrograms Hg/g) for 4 weeks. Other groups of fish were exposed...... to dissolved mercuric chloride (HgCl2, 270 micrograms Hg/liter) for 2, 6, and 12 hr, respectively. In both series of experiments, the radioisotope 203Hg was included in order to determine the accumulation of mercury in the olfactory system. Gamma-spectrometry showed that both mercury compounds accumulated...

  19. Extraction of gelatin from salmon (Salmo salar) fish skin using trypsin-aided process: optimization by Plackett-Burman and response surface methodological approaches.

    Science.gov (United States)

    Fan, HuiYin; Dumont, Marie-Josée; Simpson, Benjamin K

    2017-11-01

    Gelatin from salmon (Salmo salar) skin with high molecular weight protein chains (α-chains) was extracted using trypsin-aided process. Response surface methodology was used to optimise the extraction parameters. Yield, hydroxyproline content and protein electrophoretic profile via sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis of gelatin were used as responses in the optimization study. The optimum conditions were determined as: trypsin concentration at 1.49 U/g; extraction temperature at 45 °C; and extraction time at 6 h 16 min. This response surface optimized model was significant and produced an experimental value (202.04 ± 8.64%) in good agreement with the predicted value (204.19%). Twofold higher yields of gelatin with high molecular weight protein chains were achieved in the optimized process with trypsin treatment when compared to the process without trypsin.

  20. The effect of Cu (II) on the electro-olfactogram (EOG) of the Atlantic salmon (Salmo salar L) in artificial freshwater of varying inorganic carbon concentrations

    DEFF Research Database (Denmark)

    Winberg, S; Bjerselius, R; Baatrup, E

    1993-01-01

    The effect of inorganic copper species was studied by recording the receptor potential, electro-olfactogram (EOG), from the olfactory epithelium of Atlantic salmon (Salmo salar L). In a series of experiments, the olfactory organ was irrigated with aqueous copper solutions with concentrations...... of the free cupric ion (Cu2+) ranging from 0.2 to 9.7 microM. The diverse copper species were created by varying the amount of bicarbonate (NaHCO3) in artificial freshwater solutions of equal total copper concentrations. In general, these copper solutions induced a slow depolarization of the baseline followed...... by a hyperpolarization. The amplitudes of these variations in baseline potentials increased with increasing concentrations of Cu2+ ion, i.e., decreasing concentrations of NaHCO3. Stimulating the olfactory epithelium with L-alanine during the copper exposure evoked atypical EOG responses. The amplitudes and form...

  1. Evidence acquisition and evaluation for evidence summit on population-level behavior change to enhance child survival and development in low- and middle-income countries.

    Science.gov (United States)

    Balster, Robert L; Levy, Stephanie; Stammer, Emily

    2014-01-01

    Recognizing the need for evidence to inform public health officials and health care workers in the U.S. government and low- and middle-income country governments on efficient, effective behavior change policies, strategies, and programs for child health and development, the U.S. government convened the Evidence Summit on Enhancing Child Survival and Development in Lower- and Middle-Income Countries by Achieving Population-Level Behavior Change. This article summarizes the background and methods for the acquisition and evaluation of the evidence used to the achieve the goals of the summit that is reviewed in other articles in this special issue of the Journal of Health Communication. The process began by identifying focal questions intended to inform the U.S. and low- and middle-income governments about behavior change interventions that accelerate reductions in under-5 mortality and optimize healthy and protective child development to 5 years of age. Experts were selected representing the research and program communities, academia, relevant nongovernmental organizations, and government agencies and assembled into evidence review teams. This was followed by the systematic gathering of relevant peer-reviewed literature that would inform the focal questions. Members of the evidence review teams were invited to add relevant articles not identified in the initial literature review to complete the bibliographies. Details of the search processes and methods used for screening and quality reviews are described. The evidence review teams were asked to comply with a specific evaluation framework for recommendations on practice and policy on the basis of both expert opinion and the quality of the data reviewed.

  2. Understanding the sub-cellular dynamics of silicon transportation and synthesis in diatoms using population-level data and computational optimization.

    Directory of Open Access Journals (Sweden)

    Narjes Javaheri

    2014-06-01

    Full Text Available Controlled synthesis of silicon is a major challenge in nanotechnology and material science. Diatoms, the unicellular algae, are an inspiring example of silica biosynthesis, producing complex and delicate nano-structures. This happens in several cell compartments, including cytoplasm and silica deposition vesicle (SDV. Considering the low concentration of silicic acid in oceans, cells have developed silicon transporter proteins (SIT. Moreover, cells change the level of active SITs during one cell cycle, likely as a response to the level of external nutrients and internal deposition rates. Despite this topic being of fundamental interest, the intracellular dynamics of nutrients and cell regulation strategies remain poorly understood. One reason is the difficulties in measurements and manipulation of these mechanisms at such small scales, and even when possible, data often contain large errors. Therefore, using computational techniques seems inevitable. We have constructed a mathematical model for silicon dynamics in the diatom Thalassiosira pseudonana in four compartments: external environment, cytoplasm, SDV and deposited silica. The model builds on mass conservation and Michaelis-Menten kinetics as mass transport equations. In order to find the free parameters of the model from sparse, noisy experimental data, an optimization technique (global and local search, together with enzyme related penalty terms, has been applied. We have connected population-level data to individual-cell-level quantities including the effect of early division of non-synchronized cells. Our model is robust, proven by sensitivity and perturbation analysis, and predicts dynamics of intracellular nutrients and enzymes in different compartments. The model produces different uptake regimes, previously recognized as surge, externally-controlled and internally-controlled uptakes. Finally, we imposed a flux of SITs to the model and compared it with previous classical kinetics

  3. Is electroconvulsive therapy use among young-old and old-old adults comparable? A 10-year population-level analysis of service provision.

    Science.gov (United States)

    Plakiotis, Chris; George, Kuruvilla; OʼConnor, Daniel W

    2014-09-01

    Existing research on electroconvulsive therapy (ECT) in older adults has largely examined its efficacy and safety in treating depression, but there are few population-level studies of its use in this patient group. Our objective was to provide a comprehensive 10-year picture of ECT use among adults aged 65 years and older in the State of Victoria, Australia. We focused especially on comparing patterns of ECT use between young-old and old-old individuals, to better inform practicing physicians, policy makers, and researchers about ECT practices in this diverse range of patients. We analyzed statewide ECT service provision data from 1998 to 2007 provided by the Office of the Chief Psychiatrist of Victoria. Age-adjustment of crude data revealed that old-old adults had the highest rate of ECT use overall (especially women) as well as the highest utilization rates for depression and public sector treatment. Although the highest rate of exclusively involuntary treatment under the Mental Health Act was also observed among old-old adults, most of the old-old patients were treated on an exclusively voluntary basis. The number of ECT treatments administered to young-old and old-old patients did not differ. The higher ECT utilization rates we previously reported in older adults as a whole were further accentuated in old-old individuals. Old-old adults may have medical comorbidities and personal care needs that have implications for ECT technique and service delivery. Our findings underscore the need for greater inclusion of old-old patients in future ECT research to increase its clinical applicability.

  4. Setting Quality Improvement Priorities for Women Receiving Systemic Therapy for Early-Stage Breast Cancer by Using Population-Level Administrative Data.

    Science.gov (United States)

    Enright, Katherine A; Taback, Nathan; Powis, Melanie Lynn; Gonzalez, Alejandro; Yun, Lingsong; Sutradhar, Rinku; Trudeau, Maureen E; Booth, Christopher M; Krzyzanowska, Monika K

    2017-10-01

    Purpose Routine evaluation of quality measures (QMs) can drive improvement in cancer systems by highlighting gaps in care. Targeting quality improvement at QMs that demonstrate substantial variation has the potential to make the largest impact at the population level. We developed an approach that uses both variation in performance and number of patients affected by the QM to set priorities for improving the quality of systemic therapy for women with early-stage breast cancer (EBC). Patients and Methods Patients with EBC diagnosed from 2006 to 2010 in Ontario, Canada, were identified in the Ontario Cancer Registry and linked deterministically to multiple health care databases. Individual QMs within a panel of 15 QMs previously developed to assess the quality of systemic therapy across four domains (access, treatment delivery, toxicity, and safety) were ranked on interinstitutional variation in performance (using interquartile range) and the number of patients who were affected; then the two rankings were averaged for a summative priority ranking. Results We identified 28,427 patients with EBC who were treated at 84 institutions. The use of computerized physician electronic order entry for chemotherapy, emergency room visits or hospitalizations during chemotherapy, and timely receipt of chemotherapy were identified as the QMs that had the largest potential to improve quality of care at a system level within this cohort. Conclusion A simple ranking system based on interinstitutional variation in performance and patient volume can be used to identify high-priority areas for quality improvement from a population perspective. This approach is generalizable to other health care systems that use QMs to drive improvement.

  5. A population-level approach to promoting healthy child development and school success in low-income, urban neighborhoods: impact on parenting and child conduct problems.

    Science.gov (United States)

    Dawson-McClure, Spring; Calzada, Esther; Huang, Keng-Yen; Kamboukos, Dimitra; Rhule, Dana; Kolawole, Bukky; Petkova, Eva; Brotman, Laurie Miller

    2015-02-01

    Minority children living in disadvantaged neighborhoods are at high risk for school dropout, delinquency, and poor health, largely due to the negative impact of poverty and stress on parenting and child development. This study evaluated a population-level, family-centered, school-based intervention designed to promote learning, behavior, and health by strengthening parenting, classroom quality, and child self-regulation during early childhood. Ten schools in urban districts serving primarily low-income Black students were randomly assigned to intervention or a "pre-kindergarten education as usual" control condition. Intervention included a family program (a 13-week behavioral parenting intervention and concurrent group for children) and professional development for early childhood teachers. The majority (88 %) of the pre-kindergarten population (N = 1,050; age 4) enrolled in the trial, and nearly 60 % of parents in intervention schools participated in the family program. This study evaluated intervention impact on parenting (knowledge, positive behavior support, behavior management, involvement in early learning) and child conduct problems over a 2-year period (end of kindergarten). Intent-to-treat analyses found intervention effects on parenting knowledge, positive behavior support, and teacher-rated parent involvement. For the highest-risk families, intervention also resulted in increased parent-rated involvement in early learning and decreased harsh and inconsistent behavior management. Among boys at high risk for problems based on baseline behavioral dysregulation (age 4, 23 % of sample), intervention led to lower rates of conduct problems at age 6. Family-centered intervention at the transition to school has potential to improve population health and break the cycle of disadvantage for low-income, minority families.

  6. Schneidia zacatense sp. nov. - First population level study of Ataxioceratinae from the Lower Kimmeridgian in northern Mexico — Biostratigraphic and palaeobiogeographic significance

    Science.gov (United States)

    Villaseñor, Ana B.; Moliner, Luis; Olóriz, Federico

    2015-11-01

    Lower Kimmeridgian ataxioceratin ammonites have been reported from Mexico for a long-time. This research shows the first analysis made on a population level study based on the material collected in a bed-by-bed sampling in the Cañón de Las Bocas section, Zacatecas, north-central Mexico. Aside from obtaining ribbing curves and coiling degree values, as well as the application of image analysis for the precise identification of preserved ribbing style details, principal component and cluster analyses has been applied to evaluate morpho-grouping of those individuals providing precise values of selected variables among preserved shell features of the 323 ammonite remains collected in situ. The coiling degree and the ribbing pattern are the most useful traits for phenotype characterization and interpretation at the genus and species levels. A more intricate combination of measured phenotype features is recognized at intra-species level. The new species level taxon Schneidia zacatense sp. nov. is erected and compared with European species of the same genus. The biochronostratigraphic interpretation points to a latest Platynota Chron age, which in turn could represent a local expression of a slightly wider time range -i.e., potential, local fluctuations of the stratigraphic range assumed in Mexico for the Schneidia Assemblage cannot be ruled out at the present state of knowledge. The palaeobiogeographic analysis is approached taking into account the eco-sedimentary context derived from a particular phase in the geodynamic evolution of the Mexico-Caribbean area during Late Oxfordian to Early Kimmeridgian times. Based on the composition of the macroinvertebrate fossil assemblage analysed and its stratigraphic range, the interpreted biogeographic dynamics points to an incursion epibole, followed by ecological epibole and local extinctions events. Two alternative hypotheses are evaluated for interpreting Panthalassic against west-Tethyan origins for the colonizers. A

  7. A novel totivirus and piscine reovirus (PRV in Atlantic salmon (Salmo salar with cardiomyopathy syndrome (CMS

    Directory of Open Access Journals (Sweden)

    Nederbragt Alexander J

    2010-11-01

    Full Text Available Abstract Background Cardiomyopathy syndrome (CMS is a severe disease affecting large farmed Atlantic salmon. Mortality often appears without prior clinical signs, typically shortly prior to slaughter. We recently reported the finding and the complete genomic sequence of a novel piscine reovirus (PRV, which is associated with another cardiac disease in Atlantic salmon; heart and skeletal muscle inflammation (HSMI. In the present work we have studied whether PRV or other infectious agents may be involved in the etiology of CMS. Results Using high throughput sequencing on heart samples from natural outbreaks of CMS and from fish experimentally challenged with material from fish diagnosed with CMS a high number of sequence reads identical to the PRV genome were identified. In addition, a sequence contig from a novel totivirus could also be constructed. Using RT-qPCR, levels of PRV in tissue samples were quantified and the totivirus was detected in all samples tested from CMS fish but not in controls. In situ hybridization supported this pattern indicating a possible association between CMS and the novel piscine totivirus. Conclusions Although causality for CMS in Atlantic salmon could not be proven for either of the two viruses, our results are compatible with a hypothesis where, in the experimental challenge studied, PRV behaves as an opportunist whereas the totivirus might be more directly linked with the development of CMS.

  8. Comparative genomics identifies candidate genes for infectious salmon anemia (ISA) resistance in Atlantic salmon (Salmo salar).

    Science.gov (United States)

    Li, Jieying; Boroevich, Keith A; Koop, Ben F; Davidson, William S

    2011-04-01

    Infectious salmon anemia (ISA) has been described as the hoof and mouth disease of salmon farming. ISA is caused by a lethal and highly communicable virus, which can have a major impact on salmon aquaculture, as demonstrated by an outbreak in Chile in 2007. A quantitative trait locus (QTL) for ISA resistance has been mapped to three microsatellite markers on linkage group (LG) 8 (Chr 15) on the Atlantic salmon genetic map. We identified bacterial artificial chromosome (BAC) clones and three fingerprint contigs from the Atlantic salmon physical map that contains these markers. We made use of the extensive BAC end sequence database to extend these contigs by chromosome walking and identified additional two markers in this region. The BAC end sequences were used to search for conserved synteny between this segment of LG8 and the fish genomes that have been sequenced. An examination of the genes in the syntenic segments of the tetraodon and medaka genomes identified candidates for association with ISA resistance in Atlantic salmon based on differential expression profiles from ISA challenges or on the putative biological functions of the proteins they encode. One gene in particular, HIV-EP2/MBP-2, caught our attention as it may influence the expression of several genes that have been implicated in the response to infection by infectious salmon anemia virus (ISAV). Therefore, we suggest that HIV-EP2/MBP-2 is a very strong candidate for the gene associated with the ISAV resistance QTL in Atlantic salmon and is worthy of further study.

  9. Atlantic salmon (Salmo salar) liver transcriptome response to diets containing Camelina sativa products.

    Science.gov (United States)

    Xue, Xi; Hixson, Stefanie M; Hori, Tiago S; Booman, Marije; Parrish, Christopher C; Anderson, Derek M; Rise, Matthew L

    2015-06-01

    Due to increasing demand for fish oil (FO) and fish meal (FM) in aquafeeds, more sustainable alternatives such as plant-derived oils and proteins are needed. Camelina sativa products are viable feed ingredients given the high oil and crude protein content in the seed. Atlantic salmon were fed diets with complete or partial replacement of FO and/or FM with camelina oil (CO) and/or camelina meal (CM) in a 16-week trial [Control diet: FO; Test diets: 100% CO replacement of FO (100CO), or 100CO with solvent-extracted FM (100COSEFM), 10% CM (100CO10CM), or SEFM+10% CM (100COSEFM10CM)]. Diet composition, growth, and fatty acid analyses for this feeding trial were published previously. A 44K microarray experiment identified liver transcripts that responded to 100COSEFM10CM (associated with reduced growth) compared to controls, yielding 67 differentially expressed features (FDRcamelina-containing diet groups compared with controls. Multivariate statistics were used to correlate hepatic desaturase and elongase gene expression data with tissue fatty acid profiles, indicating the involvement of these genes in LC-PUFA biosynthesis. This nutrigenomic study provides molecular biomarkers for use in developing novel aquafeeds using camelina products. Copyright © 2015 Elsevier Inc. All rights reserved.

  10. Jellyfish as vectors of bacterial disease for farmed salmon (Salmo salar).

    Science.gov (United States)

    Ferguson, Hugh W; Delannoy, Christian M J; Hay, Stephen; Nicolson, James; Sutherland, David; Crumlish, Margaret

    2010-05-01

    Swarms or blooms of jellyfish are increasingly problematic and can result in high mortality rates of farmed fish. Small species of jellyfish, such as Phialella quadrata (13 mm in diameter), are capable of passing through the mesh of sea cages and being sucked into the mouth of fish during respiration. Results of the current study show that the initial damage to gills of farmed Atlantic salmon, likely produced by nematocyst-derived toxins from the jellyfish, was compounded by secondary bacterial infection with Tenacibaculum maritimum. Results also demonstrate that these filamentous bacteria were present on the mouth of the jellyfish and that their DNA sequences were almost identical to those of bacteria present on the salmon gills. This suggests that the bacterial lesions were not the result of an opportunistic infection of damaged tissue, as previously thought. Instead, P. quadrata is probably acting as a vector for this particular bacterial pathogen, and it is the first time that evidence to support such a link has been presented. No prior literature describing the presence of bacteria associated with jellyfish, except studies about their decay, could be found. It is not known if all jellyfish of this and other species carry similar bacteria or the relationship to each other. Their source, the role they play under other circumstances, and indeed whether the jellyfish were themselves diseased are also not known. The high proteolytic capabilities of T. maritimum mean that partially digested gill tissues were readily available to the jellyfish, which rely heavily on intracellular digestion for their nutrition.

  11. Genetic stock identification of Atlantic salmon (Salmo salar populations in the southern part of the European range

    Directory of Open Access Journals (Sweden)

    McGinnity Philip

    2010-04-01

    Full Text Available Abstract Background Anadromous migratory fish species such as Atlantic salmon (Salmo salar have significant economic, cultural and ecological importance, but present a complex case for management and conservation due to the range of their migration. Atlantic salmon exist in rivers across the North Atlantic, returning to their river of birth with a high degree of accuracy; however, despite continuing efforts and improvements in in-river conservation, they are in steep decline across their range. Salmon from rivers across Europe migrate along similar routes, where they have, historically, been subject to commercial netting. This mixed stock exploitation has the potential to devastate weak and declining populations where they are exploited indiscriminately. Despite various tagging and marking studies, the effect of marine exploitation and the marine element of the salmon lifecycle in general, remain the "black-box" of salmon management. In a number of Pacific salmonid species and in several regions within the range of the Atlantic salmon, genetic stock identification and mixed stock analysis have been used successfully to quantify exploitation rates and identify the natal origins of fish outside their home waters - to date this has not been attempted for Atlantic salmon in the south of their European range. Results To facilitate mixed stock analysis (MSA of Atlantic salmon, we have produced a baseline of genetic data for salmon populations originating from the largest rivers from Spain to northern Scotland, a region in which declines have been particularly marked. Using 12 microsatellites, 3,730 individual fish from 57 river catchments have been genotyped. Detailed patterns of population genetic diversity of Atlantic salmon at a sub-continent-wide level have been evaluated, demonstrating the existence of regional genetic signatures. Critically, these appear to be independent of more commonly recognised terrestrial biogeographical and political

  12. Influence of Fishmeal-Free Diets on Microbial Communities in Atlantic Salmon (Salmo salar) Recirculation Aquaculture Systems.

    Science.gov (United States)

    Schmidt, Victor; Amaral-Zettler, Linda; Davidson, John; Summerfelt, Steven; Good, Christopher

    2016-08-01

    Reliance on fishmeal as a primary protein source is among the chief economic and environmental concerns in aquaculture today. Fishmeal-based feeds often require harvest from wild fish stocks, placing pressure on natural ecosystems and causing price instability. Alternative diet formulations without the use of fishmeal provide a potential solution to this challenge. Although the impact of alternative diets on fish performance, intestinal inflammation, palatability, and gut microbiota has been a topic of recent interest, less is known about how alternative feeds impact the aquaculture environment as a whole. The recent focus on recirculating aquaculture systems (RAS) and the closed-containment approach to raising food fish highlights the need to maintain stable environmental and microbiological conditions within a farm environment. Microbial stability in RAS biofilters is particularly important, given its role in nutrient processing and water quality in these closed systems. If and how the impacts of alternative feeds on microbial communities in fish translate into changes to the biofilters are not known. We tested the influence of a fishmeal-free diet on the microbial communities in RAS water, biofilters, and salmon microbiomes using high-throughput 16S rRNA gene V6 hypervariable region amplicon sequencing. We grew Atlantic salmon (Salmo salar) to market size in six replicate RAS tanks, three with traditional fishmeal diets and three with alternative-protein, fishmeal-free diets. We sampled intestines and gills from market-ready adult fish, water, and biofilter medium in each corresponding RAS unit. Our results provide data on how fish diet influences the RAS environment and corroborate previous findings that diet has a clear influence on the microbiome structure of the salmon intestine, particularly within the order Lactobacillales (lactic acid bacteria). We conclude that the strong stability of taxa likely involved in water quality processing regardless of diet (e

  13. Comparison of laboratory single species and field population-level effects of the pyrethroid insecticide lambda-cyhalothrin on freshwater invertebrates.

    Science.gov (United States)

    Schroer, A F W; Belgers, J D M; Brock, T C M; Matser, A M; Maund, S J; Van den Brink, P J

    2004-04-01

    The toxicity of the pyrethroid insecticide lambda-cyhalothrin to freshwater invertebrates has been investigated using data from short-term laboratory toxicity tests and in situ bioassays and population-level effects in field microcosms. In laboratory tests, patterns of toxicity were consistent with previous data on pyrethroids. The midge Chaoborus obscuripes was most sensitive (48- and 96-h EC50 = 2.8 ng/L). Other insect larvae (Hemiptera, Ephemeroptera) and macrocrustacea (Amphipoda, Isopoda) were also relatively sensitive, with 48- and 96-h EC50 values between 10 and 100 ng/L. Generally, microcrustacea (Cladocera, Copepoda) and larvae of certain insect groups (Odonata and Chironomidae) were less sensitive, with 48-h EC50 values higher than 100 ng/L. Mollusca and Plathelminthes were insensitive and were unaffected at concentrations at and above the water solubility (5 microg/L). Generally, the EC50 values based on initial population responses in field enclosures were similar to values derived from laboratory tests with the same taxa. Also, the corresponding fifth and tenth percentile hazard concentrations (HC5 and HC10) were similar (laboratory HC5 = 2.7 ng/L and field HC5 = 4.1 ng/L; laboratory and field HC10 = 5.1 ng/L), at least when based on the same sensitive taxonomic groups (insects and crustaceans) and when a similar concentration range was taken into account. In the three field enclosure experiments and at a treatment level of 10 ng/L, consistent effects were observed for only one population (Chaoborus obscuripes), with recovery taking place within 3 to 6 weeks. The laboratory HC5 (2.7 ng/L) and HC10 (5.1 ng/L) based on acute EC50 values of all aquatic arthropod taxa were both lower than this 10 ng/L, a concentration that might represent the "regulatory acceptable concentration." The HC5 and HC10 values in this study in The Netherlands (based on static laboratory tests with freshwater arthropods) were very similar to those derived from a previous study in

  14. Population-level reduction in adult mortality after extension of free anti-retroviral therapy provision into rural areas in northern Malawi.

    Science.gov (United States)

    Floyd, Sian; Molesworth, Anna; Dube, Albert; Banda, Emmanuel; Jahn, Andreas; Mwafulirwa, Charles; Ngwira, Bagrey; Branson, Keith; Crampin, Amelia C; Zaba, Basia; Glynn, Judith R; French, Neil

    2010-10-19

    Four studies from sub-Saharan Africa have found a substantial population-level effect of ART provision on adult mortality. It is important to see if the impact changes with time since the start of treatment scale-up, and as treatment moves to smaller clinics. During 2002-4 a demographic surveillance site (DSS) was established in Karonga district, northern Malawi. Information on births and deaths is collected monthly, with verbal autopsies conducted for all deaths; migrations are updated annually. We analysed mortality trends by comparing three time periods: pre-ART roll-out in the district (August 2002-June 2005), ART period 1 (July 2005-September 2006) when ART was available only in a town 70 km away, and ART period 2 (October 2006-September 2008), when ART was available at a clinic within the DSS area. HIV prevalence and ART uptake were estimated from a sero-survey conducted in 2007/2008. The all-cause mortality rate among 15-59 year olds was 10.2 per 1000 person-years in the pre-ART period (288 deaths/28285 person-years). It fell by 16% in ART period 1 and by 32% in ART period 2 (95% CI 18%-43%), compared with the pre-ART period. The AIDS mortality rate fell from 6.4 to 4.6 to 2.7 per 1000 person-years in the pre-ART period, period 1 and period 2 respectively (rate ratio for period 2 = 0.43, 95% CI 0.33-0.56). There was little change in non-AIDS mortality. Treatment coverage among individuals eligible to start ART was around 70% in 2008. ART can have a dramatic effect on mortality in a resource-constrained setting in Africa, at least in the early years of treatment provision. Our findings support the decentralised delivery of ART from peripheral health centres with unsophisticated facilities. Continued funding to maintain and further scale-up treatment provision will bring large benefits in terms of saving lives.

  15. Parental recommendations for population level interventions to support infant and family dietary choices: a qualitative study from the Growing Up in Wales, Environments for Healthy Living (EHL) study.

    Science.gov (United States)

    Khanom, Ashrafunnesa; Hill, Rebecca A; Morgan, Kelly; Rapport, Frances L; Lyons, Ronan A; Brophy, Sinead

    2015-03-11

    Childhood obesity presents a challenge to public health. This qualitative study explored the main barriers to dietary choices faced by parents with infants, and the types of interventions and policy level recommendations they would like to see put in place, to promote a healthier food environment. 61 semi-structured interviews with prospective parents and parents of infants (61 mothers and 35 fathers) were conducted. Families were selected according to community deprivation levels using the Townsend Deprivation Index to ensure a representative sample from deprived and affluent neighbourhoods. Inductive thematic analysis was used to analyse the data. Parents identified triggers which led to unhealthy dietary choices such as reliance on fast food outlets due to; shift work, lack of access to personal transport, inability to cook, their own childhood dietary experiences, peer pressure and familial relationships. Parents who made healthy dietary choices reported learning cooking skills while at university, attending community cooking classes, having access to quality food provided by church and community organisations or access to Healthy Start vouchers. They called for a reduction in supermarket promotion of unhealthy food and improved access to affordable and high-quality fresh produce in the local area and in supermarkets. There was a strong message to policy makers to work with commercial companies (food manufactures) as they have resources to lower costs and target messages at a diverse population. Provision of targeted advice to fathers, minority ethnic parents, and tailored and practical advice and information on how to purchase, prepare, store and cook food was requested, along with community cookery classes and improved school cookery lessons. There is a need for parent directed community/population level interventions that aims to reduce socio-ecological barriers to making healthy dietary choices. Parents desired improvements in meals provided in workplaces

  16. Stem xylem resistance to cavitation is related to xylem structure but not to growth and water-use efficiency at the within-population level in Populus nigra L.

    Science.gov (United States)

    Guet, Justine; Fichot, Régis; Lédée, Camille; Laurans, Françoise; Cochard, Hervé; Delzon, Sylvain; Bastien, Catherine; Brignolas, Franck

    2015-08-01

    Xylem resistance to drought-induced cavitation is a key trait of plant water relations. This study assesses the genetic variation expressed for stem cavitation resistance within a population of a riparian species, the European black poplar (Populus nigra L.), and explores its relationships with xylem anatomy, water-use efficiency (WUE), and growth. Sixteen structural and physiological traits related to cavitation resistance, xylem anatomy, growth, bud phenology, and WUE were measured on 33 P. nigra genotypes grown under optimal irrigation in a 2-year-old clonal experiment in a nursery. Significant genetic variation was expressed for the xylem tension inducing 50% loss of hydraulic conductivity (Ψ50) within the studied population, as attested by the high value of broad-sense heritability estimated for this trait (H (2) ind = 0.72). Stem cavitation resistance was associated with xylem structure: the more cavitation-resistant genotypes exhibited lower hydraulic efficiency and higher mechanical reinforcement as assessed from stem xylem cross sections. By contrast, Ψ50 was not significantly related to shoot height increment, total above-ground dry mass, or bulk leaf carbon isotope discrimination, a proxy for intrinsic WUE. These findings indicate that the trade-offs between xylem resistance to cavitation, hydraulic efficiency, and mechanical reinforcement can occur at the within-population level. Given that the studied genotypes were exposed to the same environmental conditions and evolutionary drivers in situ, the trade-offs detected at this scale are expected to reflect true functional relationships. © The Author 2015. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  17. Testes and brain gene expression in precocious male and adult maturing Atlantic salmon (Salmo salar)

    Science.gov (United States)

    2010-01-01

    Background The male Atlantic salmon generally matures in fresh water upon returning after one or several years at sea. Some fast-growing male parr develop an alternative life strategy where they sexually mature before migrating to the oceans. These so called 'precocious' parr or 'sneakers' can successfully fertilise adult female eggs and so perpetuate their line. We have used a custom-built cDNA microarray to investigate gene expression changes occurring in the salmon gonad and brain associated with precocious maturation. The microarray has been populated with genes selected specifically for involvement in sexual maturation (precocious and adult) and in the parr-smolt transformation. Results Immature and mature parr collected from a hatchery-reared stock in January were significantly different in weight, length and condition factor. Changes in brain expression were small - never more than 2-fold on the microarray, and down-regulation of genes was much more pronounced than up-regulation. Significantly changing genes included isotocin, vasotocin, cathepsin D, anamorsin and apolipoprotein E. Much greater changes in expression were seen in the testes. Among those genes in the testis with the most significant changes in expression were anti-Mullerian hormone, collagen 1A, and zinc finger protein (Zic1), which were down-regulated in precocity and apolipoproteins E and C-1, lipoprotein lipase and anti-leukoproteinase precursor which were up-regulated in precocity. Expression changes of several genes were confirmed in individual fish by quantitative PCR and several genes (anti-Mullerian hormone, collagen 1A, beta-globin and guanine nucleotide binding protein (G protein) beta polypeptide 2-like 1 (GNB2L1) were also examined in adult maturing testes. Down-regulation of anti-Mullerian hormone was judged to be greater than 160-fold for precocious males and greater than 230-fold for November adult testes in comparison to July testes by this method. For anti-Mullerian hormone

  18. Testes and brain gene expression in precocious male and adult maturing Atlantic salmon (Salmo salar).

    Science.gov (United States)

    Guiry, Aoife; Flynn, Denis; Hubert, Sophie; O'Keeffe, Allan M; LeProvost, Olivier; White, Samantha L; Forde, Patrick F; Davoren, Pamela; Houeix, Benoit; Smith, Terry J; Cotter, Deirdre; Wilkins, Noel P; Cairns, Michael T

    2010-03-30

    The male Atlantic salmon generally matures in fresh water upon returning after one or several years at sea. Some fast-growing male parr develop an alternative life strategy where they sexually mature before migrating to the oceans. These so called 'precocious' parr or 'sneakers' can successfully fertilise adult female eggs and so perpetuate their line. We have used a custom-built cDNA microarray to investigate gene expression changes occurring in the salmon gonad and brain associated with precocious maturation. The microarray has been populated with genes selected specifically for involvement in sexual maturation (precocious and adult) and in the parr-smolt transformation. Immature and mature parr collected from a hatchery-reared stock in January were significantly different in weight, length and condition factor. Changes in brain expression were small - never more than 2-fold on the microarray, and down-regulation of genes was much more pronounced than up-regulation. Significantly changing genes included isotocin, vasotocin, cathepsin D, anamorsin and apolipoprotein E. Much greater changes in expression were seen in the testes. Among those genes in the testis with the most significant changes in expression were anti-Mullerian hormone, collagen 1A, and zinc finger protein (Zic1), which were down-regulated in precocity and apolipoproteins E and C-1, lipoprotein lipase and anti-leukoproteinase precursor which were up-regulated in precocity. Expression changes of several genes were confirmed in individual fish by quantitative PCR and several genes (anti-Mullerian hormone, collagen 1A, beta-globin and guanine nucleotide binding protein (G protein) beta polypeptide 2-like 1 (GNB2L1) were also examined in adult maturing testes. Down-regulation of anti-Mullerian hormone was judged to be greater than 160-fold for precocious males and greater than 230-fold for November adult testes in comparison to July testes by this method. For anti-Mullerian hormone and guanine

  19. Testes and brain gene expression in precocious male and adult maturing Atlantic salmon (Salmo salar

    Directory of Open Access Journals (Sweden)

    Houeix Benoit

    2010-03-01

    Full Text Available Abstract Background The male Atlantic salmon generally matures in fresh water upon returning after one or several years at sea. Some fast-growing male parr develop an alternative life strategy where they sexually mature before migrating to the oceans. These so called 'precocious' parr or 'sneakers' can successfully fertilise adult female eggs and so perpetuate their line. We have used a custom-built cDNA microarray to investigate gene expression changes occurring in the salmon gonad and brain associated with precocious maturation. The microarray has been populated with genes selected specifically for involvement in sexual maturation (precocious and adult and in the parr-smolt transformation. Results Immature and mature parr collected from a hatchery-reared stock in January were significantly different in weight, length and condition factor. Changes in brain expression were small - never more than 2-fold on the microarray, and down-regulation of genes was much more pronounced than up-regulation. Significantly changing genes included isotocin, vasotocin, cathepsin D, anamorsin and apolipoprotein E. Much greater changes in expression were seen in the testes. Among those genes in the testis with the most significant changes in expression were anti-Mullerian hormone, collagen 1A, and zinc finger protein (Zic1, which were down-regulated in precocity and apolipoproteins E and C-1, lipoprotein lipase and anti-leukoproteinase precursor which were up-regulated in precocity. Expression changes of several genes were confirmed in individual fish by quantitative PCR and several genes (anti-Mullerian hormone, collagen 1A, beta-globin and guanine nucleotide binding protein (G protein beta polypeptide 2-like 1 (GNB2L1 were also examined in adult maturing testes. Down-regulation of anti-Mullerian hormone was judged to be greater than 160-fold for precocious males and greater than 230-fold for November adult testes in comparison to July testes by this method. For

  20. Variation in population levels of physical activity in European children and adolescents according to cross-European studies: a systematic literature review within DEDIPAC

    NARCIS (Netherlands)

    Hecke, L. van; Loyen, A.; Verloigne, M.; Ploeg, H.P. van der; Lakerveld, J.; Brug, J.; Bourdeaudhuij, I. de; Ekelund, U.; Donnelly, A.; Hendriksen, I.; Deforche, B.

    2016-01-01

    Background: Regular physical activity is associated with physical, social and mental health benefits, whilst insufficient physical activity is associated with several negative health outcomes (e.g. metabolic problems). Population monitoring of physical activity is important to gain insight into

  1. Influencia del α-tocoferol en la incorporación y peroxidación del ácido araquidónico en alevines parr de salmón del Atlántico (Salmo salar L. Influence of α-tocopherol on arachidonic acid deposition and peroxidation in Atlantic salmon (Salmo salar L. fingerlings

    Directory of Open Access Journals (Sweden)

    Patricio Dantagnan

    2012-09-01

    Full Text Available Se evaluó el efecto sinérgico del ácido araquidónico (ARA (20:4n-6 y el α-tocoferol en la acumulación de estos nutrientes y su peroxidación en el músculo e hígado en juveniles de salmón del Atlántico (Salmo salar. Grupos por triplicado se alimentaron por 12 semanas con ocho dietas experimentales que contenían diferentes niveles de ácido araquidónico y α-tocoferol. Los parámetros productivos no se vieron afectados (P > 0,05 por las dietas suministradas. La acumulación del ARA en el músculo e hígado mostró diferencias significativas (P The synergistic effect of arachidonic acid (ARA (20:4n-6 and α-tocopherol on the accumulation of fatty acids and the peroxidation of lipids in liver and muscle was evaluated in Atlantic salmon (Salmo salar juveniles. Triplicate groups were fed during 12 weeks with eight experimental diets with different levels of ARA and α-tocopherol. In all experimental diets the productive parameters were not affected (P > 0.05. ARA accumulation in muscle and liver showed significant differences (P < 0.05 between treatments. The synergic relationship between ARAAx4ocopherol was influenced (P < 0.05 only in the liver, showing that high levels of α-tocopherol and ARA favored the fatty acids accumulation in this organ. Results indicate that a dietary concentration up to 0.6% ARA, the increment of α-tocopherol is not necessary. The data obtained in this study demonstrated that the interaction between the ARA and α-tocopherol influenced the accumulation of fatty acids in the liver.

  2. FRAME SENTENCES WITH ADVERB-VERB AT SALAR TURKISH AND VIEW OF ADVERB-VERB MARKERS SALAR TÜRKÇESİNDE ZARF-FİİLLİ ÖGE CÜMLELER VE ZARF- FİİLL İŞARETLEYİCİLERİNİN GÖRÜNÜMÜ

    Directory of Open Access Journals (Sweden)

    Gülsün MEHMET

    2010-10-01

    Full Text Available At the Turkish language, non finite, structural independent, finished, verb cores are infinitized by the markers which are appropriate to Turkish with upper structure (at a syntactic level and connected to the concerned syntactic head. These frame sentences are called as verbal noun, verbal adjective and verbal adverb sentences at the classic grammar. Verbal adverb markers make up the basis of the forming a compound structured sentence at the Turkish language. Verbal adverb markers at the Turkish language, take in charge as a kind of action art’s installation or modal verb items which is complementary and describes judgment sorter, depicture of the main verb’s movement from all sides. Nowadays, although the structure of verbal noun and verbal adjective compound sentence at the Salar Turkish which is being spoken by 100.000 (one hundred thousand Salar Turk at the Qing – hai state of People’s Republic of China becomes less, verbal adverb structured sentence forming looks like working strongly. There is not any compound sentence which is formed with conjunction at Salar language. Actions combine the rich verbal adverb markers. Furthermore verbal adverbs are so interesting from the point of detecting the existing local dialect for Salar language and reflecting the characteristics of mixed dialect besides this. Türk dilinde derin yapıda (deep structure çekimlenmiş olan, şekilce bağımsız, bitmiş (finished önermelerin yüklem çekirdekleri, üst yapıda (sentaktik düzlemde Türkçeye özgü işaretleyiciler ile ögeleştirilir (infinitization ve ilgili olduğu sentaktik başa (syntactic head bağlanır. Bu öge cümleler klasik gramerlerde isim-fiil, sıfat-fiil ve zarf-fiil cümleleri olarak adlandırılır. Zarf-fiil işaretleyicileri Türk dilinin birleşik yapılı cümle kurulumuna temel oluşturur. Türk dilinde zarf-fiil işaretleyicileri yargı sıralayıcısı (judgements sorter, ana yüklemdeki hareketi türlü y

  3. Using height-for-age differences (HAD) instead of height-for-age z-scores (HAZ) for the meaningful measurement of population-level catch-up in linear growth in children less than 5 years of age.

    Science.gov (United States)

    Leroy, Jef L; Ruel, Marie; Habicht, Jean-Pierre; Frongillo, Edward A

    2015-10-06

    Evidence from studies conducted in nutritionally deprived children in low- and middle-income countries (LIMC) in past decades showed little or no population-level catch-up in linear growth (mostly defined as reductions in the absolute height deficit) after 2 years of age. Recent studies, however, have reported population-level catch-up growth in children, defined as positive changes in mean height-for-age z-scores (HAZ). The aim of this paper was to assess whether population-level catch-up in linear growth is found when height-for-age difference (HAD: child's height compared to standard, expressed in centimeters) is used instead of HAZ. Our premise is that HAZ is inappropriate to measure changes in linear growth over time because they are constructed using standard deviations from cross-sectional data. We compare changes in growth in populations of children between 2 and 5 years using HAD vs. HAZ using cross-sectional data from 6 Demographic and Health Surveys (DHS) and longitudinal data from the Young Lives and the Consortium on Health-Orientated Research in Transitional Societies (COHORTS) studies. Using HAD, we find not only an absence of population-level catch-up in linear growth, but a continued deterioration reflected in a decrease in mean HAD between 2 and 5 years; by contrast, HAZ shows either no change (DHS surveys) or an improvement in mean HAZ (some of the longitudinal data). Population-level growth velocity was also lower than expected (based on standards) in all four Young Lives data sets, confirming the absence of catch-up growth in height. We show no evidence of population-level catch-up in linear growth in children between 2 to 5 years of age when using HAD (a measure more appropriate than HAZ to document changes as populations of children age), but a continued deterioration reflected in a decrease in mean HAD. The continued widening of the absolute height deficit after 2 years of age does not challenge the critical importance of investing in

  4. Detection of emamectin benzoate tolerance emergence in different life stages of sea lice, Lepeophtheirus salmonis, on farmed Atlantic salmon, Salmo salar L.

    Science.gov (United States)

    Jones, P G; Hammell, K L; Gettinby, G; Revie, C W

    2013-03-01

    Emamectin benzoate has been used to treat sea lice, Lepeophtheirus salmonis, infestations on farmed Atlantic salmon, Salmo salar. Recent evidence suggests a reduction in effectiveness in some locations. A major challenge in the detection of tolerance emergence can be the typically low proportion of resistant individuals in a population during the early phases. The objectives of this study were to develop a method for determining differences in temporal development of tolerance between sea lice life stages and to explore how these differences might be used to improve the monitoring of treatment effectiveness in a clinical setting. This study examined two data sets based on records of sea lice abundance following emamectin benzoate treatments from the west coast of Scotland (2002-2006) and from New Brunswick, Canada (2004-2008). Life stages were categorized into two groups (adult females and the remaining mobile stages) to examine the trends in mean abundance and treatment effectiveness. Differences in emamectin benzoate effectiveness were found between the two groups by year and location, suggesting that an important part of monitoring drug resistance development in aquatic ectoparasites may be the need to focus on key life stages. © 2013 Blackwell Publishing Ltd.

  5. Molecular analysis of enrichment cultures of ammonia oxidizers from the Salar de Huasco, a high altitude saline wetland in northern Chile.

    Science.gov (United States)

    Dorador, Cristina; Busekow, Annika; Vila, Irma; Imhoff, Johannes F; Witzel, Karl-Paul

    2008-05-01

    We analyzed enrichment cultures of ammonia-oxidizing bacteria (AOB) collected from different areas of Salar de Huasco, a high altitude, saline, pH-neutral water body in the Chilean Altiplano. Samples were inoculated into mineral media with 10 mM NH4+ at five different salt concentrations (10, 200, 400, 800 and 1,400 mM NaCl). Low diversity (up to three phylotypes per enrichment) of beta-AOB was detected using 16S rDNA and amoA clone libraries. Growth of beta-AOB was only recorded in a few enrichment cultures and varied according to site or media salinity. In total, five 16S rDNA and amoA phylotypes were found which were related to Nitrosomonas europaea/Nitrosococcus mobilis, N. marina and N. communis clusters. Phylotype 1-16S was 97% similar with N. halophila, previously isolated from Mongolian soda lakes, and phylotypes from amoA sequences were similar with yet uncultured beta-AOB from different biofilms. Sequences related to N. halophila were frequently found at all salinities. Neither gamma-AOB nor ammonia-oxidizing Archaea were recorded in these enrichment cultures.

  6. Water quality limits for Atlantic salmon (Salmo salar L.) exposed to short term reductions in pH and increased aluminum simulating episodes

    Science.gov (United States)

    Kroglund, F.; Rosseland, B. O.; Teien, H.-C.; Salbu, B.; Kristensen, T.; Finstad, B.

    2008-03-01

    Acidification has caused the loss or reduction of numerous Atlantic salmon (Salmo salar L.) populations on both sides of the North Atlantic. Acid deposition peaked in the 1980's and resulted in both chronically and episodically acidified rivers. At present, water quality is improving in all affected rivers due to reduced acid deposition. However, spring snow melt, heavy rainfall and sea salt episodes can still cause short term drops in pH and elevated concentrations of bioavailable aluminum. Technical malfunction in lime dozers will cause short termed episodic spates in the limed rivers. The current situation has prompted a need for dose-response relationships based on short term exposures of Atlantic salmon to assess the potential population effects of episodic acidification. Water quality guidelines for salmon have been lacking, despite a large number of experiments, all demonstrating dose-response relationships between water chemistry and fish health. We have summarized results from 347 short-term (10 days) at an Al dose resulting in a gill Al concentration of up to 300 µg Alg-1 dw, a 3 day exposure resulting in a gill Al accumulation in the range of 25 to 60 µg Alg-1 dw reduces smolt to adult survival in a dose related manner by 20 to 50%. For smolt to adult survival, the biological significant response is delayed relative to the dose and occurs first after the fish enters the marine environment. In addition to exposure intensity and timing, exposure duration is important for the setting of critical limits.

  7. Evaluation of feed and feeding regime on growth performance, flesh quality and fecal viscosity of Atlantic salmon ( Salmo salar L.) in recirculating aquaculture systems

    Science.gov (United States)

    Sun, Guoxiang; Liu, Ying; Li, Yong; Li, Xian; Wang, Shunkui

    2015-10-01

    The effects of different feeds and feeding regimes on growth performance, flesh quality and fecal viscosity of Atlantic salmon ( Salmo salar L.) in recirculating aquaculture systems (RAS) were investigated. Fish (initial body weight of 1677 g ± 157 g) were fed with four commercial feeds (Nosan salmon-NS, Aller gold-AG, Skretting salmon-SS and Han ye-HY) in two feeding regimes (80% and 100% satiation) for 78 d. The results showed that salmon specific growth ratio (SGR) and weight gain ratio (WGR) were significantly affected by feed type and feeding regime ( P enzymes including protease, lipase and amylase were also significantly affected by feed type and feeding regime ( P pH among all groups showed significant differences ( P < 0.05), ranging from 26.67 to 29.67, while no obvious difference was found in flesh color. Fecal viscosity for different treatments showed no significant difference, though improvement was found in 100% satiation group. From present experiment, it was concluded that both feed type and feeding regime can affect the important quality attributes of Atlantic salmon.

  8. The ecological coherence of temperature and salinity tolerance interaction and pigmentation in a non-marine vibrio isolated from Salar de Atacama

    Directory of Open Access Journals (Sweden)

    Karem Gallardo

    2016-12-01

    Full Text Available The occurrence of microorganisms from the Vibrio genus in saline lakes from northern Chile had been evidenced using Numerical Taxonomy decades before and, more recently, by phylogenetic analyses of environmental samples and isolates. Most of the knowledge about this genus came from marine isolates and showed temperature and salinity to be integral agents in shaping the niche of the Vibrio populations. The stress tolerance phenotypes of Vibrio sp. Teb5a1 isolated from Salar de Atacama was investigated. It was able to grow without NaCl and tolerated up to 100 g/L of the salt. Furthermore, it grew between 17° and 49°C (optimum 30°C in the absence of NaCl, and the range was expanded into cold temperature (4-49°C in the presence of the salt. Other additional adaptive strategies were observed in response to the osmotic stress: pigment production, identified as the known antibacterial prodigiosin, swimming and swarming motility and synthesis of a polar flagellum. It is possible to infer that environmental congruence might explain the cellular phenotypes observed in Vibrio sp. considering that coupling between temperature and salinity tolerance, the production of antibacterial agents at higher temperatures, flagellation and motility increase the chance of Vibrio sp. to survive in salty environments with high daily temperature swings and UV radiation.

  9. Dévalaison et survie d'alevins de saumon atlantique (Salmo salar L. en milieu semi-naturel contrôlé

    Directory of Open Access Journals (Sweden)

    BEALL E.

    1983-04-01

    Full Text Available Dans un chenal artificiel expérimental, des œufs de saumon atlantique (Salmo salar L. ont été pondus naturellement ou ont été enfouis au stade embryonné. A la fin de la résorption de la vésicule, une fraction importante des alevins survivants dévale de la zone de frayère. La dévalaison semble stimulée par des baisses de niveau ou des hausses de température et ralentie en période de pleine lune. D'autres facteurs pouvant être responsables de cette dévalaison sont discutés. La survie jusqu'à la collecte de tous les alevins est estimée à 74 p. 100 pour les sujets issus de la reproduction naturelle et est égale à 80 p. 100 pour ceux issus d'œufs introduits dans le gravier au stade embryonné. Des comparaisons entre ces résultats et ceux obtenus dans d'autres chenaux de fraie ou en milieu naturel montrent la validité de cette méthode pour la production d'alevins de saumon atlantique destinés au repeuplement.

  10. The effect of vaccination, ploidy and smolt production regime on pathological melanin depositions in muscle tissue of Atlantic salmon, Salmo salar L.

    Science.gov (United States)

    Larsen, H A S; Austbø, L; Nødtvedt, A; Fraser, T W K; Rimstad, E; Fjelldal, P G; Hansen, T; Koppang, E O

    2014-04-01

    The presence of melanin in muscle fillets of farmed salmon represents a considerable quality problem for the salmon industry with major economic concerns. In this study, we have examined the presence of abnormal pigmentation in vaccinated versus unvaccinated Atlantic salmon, Salmo salar L., and evaluated possible differences between diploid and triploid fish. Furthermore, the impact of the smolt production regime at ambient (4.5 °C) versus elevated temperature (16 °C) was investigated. Pigmented muscle spots were analysed for the expression of genes involved in melanization (tyrosinase gene family) and immune-related response in addition to morphological investigations. The proportion of fish with intramuscular melanin deposits was not significantly different between vaccinated and unvaccinated fish, regardless of ploidy. However, an interaction between vaccination and smolt regime was shown, where smoltification at elevated temperature after vaccination increased the number of affected individuals compared with vaccination followed by simulated natural smoltification. Furthermore, there were overall more fish with melanin spots amongst the triploids compared with their diploid counterparts. Transcription of the tyrosinase gene family confirmed an onsite melanogenesis in all pigment spots. The histological examination and the expression of the immune-related genes revealed a chronic polyphasic myopathy that was not affected by vaccination, ploidy or smolt production regime. © 2013 John Wiley & Sons Ltd.

  11. Food deprivation causes rapid changes in the abundance and glucidic composition of the cutaneous mucous cells of Atlantic salmon Salmo salar L.

    Science.gov (United States)

    Landeira-Dabarca, A; Álvarez, M; Molist, P

    2014-10-01

    Cutaneous mucus is the first physical and chemical barrier of fish. This slime layer is secreted by mucous cells located in the epidermis and is mainly composed of glycoproteins that have their origin in the diet. Therefore, food deprivation can potentially change the abundance and glucidic nature of skin mucous cells, thus changing the mucus properties. To test this hypothesis, we conducted an experiment with Atlantic salmon, Salmo salar L. Changes in the number and glucidic nature of epidermal mucus cells were analysed using standard techniques. The outcome of this study shows that food deprivation caused a rapid decrease in the density of epidermal mucous cells in Atlantic salmon. Lectin histochemistry revealed a change in the presence and stainability of some sugar residues in the mucous cells of unfed fish compared with fed fish. Given that the primary reason for mucus secretion in fish is for protection against infections, we speculate that the changes in the mucus properties caused by nutritional stress may affect their disease resistance. This fact is particularly important for fish that spend a period of time deprived of food, either as a part of their natural life cycle, or as part of farming practices. © 2013 John Wiley & Sons Ltd.

  12. Presence of Anisakis simplex (Rudolphi, 1809 det. Krabbe, 1878) and Hysterothylacium aduncum (Rudolphi, 1802) (Nematoda; Anisakidae) in runts of farmed Atlantic salmon, Salmo salar L.

    Science.gov (United States)

    Mo, T A; Gahr, A; Hansen, H; Hoel, E; Oaland, Ø; Poppe, T T

    2014-02-01

    One hundred farmed Atlantic salmon, Salmo salar L., were examined for the presence of nematodes by digestion of tissue in HCl-pepsin solution. All fish were sampled from one cage in a fish farm on the Norwegian south-west coast. Fifty harvest quality salmon, that is, salmon for human consumption (mean 5.4 kg, variation 3.0-7.6 kg), were sampled at the processing line while 50 salmon runts (mean 1.1 kg, variation 0.4-1.8 kg), discarded due to poor performance, were sampled from the discard bin after the grading station. Runts are individual fish with clear signs of poor performance over time and abnormal appearance and are thus not processed for human consumption. No nematodes were found in the musculature or viscera of the 50 harvest quality salmon. In total, 75 nematodes were found in 10 (20%) of the runts; 53 nematodes in the viscera and 22 in the musculature. Nematodes in the musculature were identified as Anisakis simplex (Rudolphi, 1809 det. Krabbe, 1878), while nematodes in the viscera were identified as A. simplex and Hysterothylacium aduncum (Rudolphi, 1802). © 2013 John Wiley & Sons Ltd.

  13. Bona fide evidence for natural vertical transmission of infectious salmon anemia virus in freshwater brood stocks of farmed Atlantic salmon (Salmo salar) in Southern Chile.

    Science.gov (United States)

    Marshall, Sergio H; Ramírez, Ramón; Labra, Alvaro; Carmona, Marisela; Muñoz, Cristián

    2014-06-01

    Infectious salmon anemia (ISA) is a severe disease that affects farmed Atlantic salmon (Salmo salar), causing outbreaks in seawater in most salmon-producing countries worldwide, with particular aggressiveness in southern Chile. The etiological agent of this disease is a virus belonging to the Orthomyxoviridae family, named infectious salmon anemia virus (ISAV). Although it has been suggested that this virus can be vertically transmitted, even in freshwater, there is a lack of compelling experimental evidence to confirm this. Here we demonstrate significant putative viral loads in the ovarian fluid as well as in the eggs of two brood stock female adult specimens that harbored the virus systemically but without clinical signs. The target virus corresponded to a highly polymorphic region 3 (HPR-3) variant, which is known to be virulent in seawater and responsible for recent and past outbreaks of this disease in Chile. Additionally, the virus recovered from the fluid as well as from the interior of the eggs was fully infective to a susceptible fish cell line. To our knowledge, this is the first robust evidence demonstrating mother-to-offspring vertical transmission of the infective virus on the one hand and the asymptomatic transmission of a virulent form of the virus in freshwater fish on the other hand. The robustness of the data presented here will contribute to a better understanding of the biology of the virus but most importantly will constitute a key management tool in the control of an aggressive agent constantly threatening the sustainability of the global salmon industry.

  14. The effects of dietary lipid and strain difference on polyunsaturated fatty acid composition and conversion in anadromous and landlocked salmon (Salmo salar L.) parr.

    Science.gov (United States)

    Rollin, Xavier; Peng, Jinglan; Pham, Diep; Ackman, Robert G; Larondelle, Yvan

    2003-02-01

    Five experimental diets containing different proportions of olive, sunflower and linseed oils were used in a 55-day feeding trial on both anadromous and landlocked parr of Atlantic salmon (Salmo salar) of the same age, in order to study the effects of diet and strain on growth and fatty acid composition and absolute gains in fish whole body triacylglycerols (TAG) and phospholipids (PL). Growth rate was higher in landlocked than in anadromous parr, but not between the different diets. By contrast, the effect of diet on whole body fatty acid composition was much more pronounced than that of strain difference. The fatty acids deposition results establish significant (Pbody TAG and PL of both stocks. They also indicate the selective deposition of 18:1n-9 compared with linoleic acid (LLA) and linolenic acid (LNA). Finally, the results suggest the occurrence of the conversion of LLA and LNA to long-chain polyunsaturated fatty acids, its stimulation by increased substrate availability, a significantly higher n-3 and n-6 polyunsaturated fatty acids conversion capacity in landlocked than in anadromous parr and a strong genetic influence on docosahexaenoic acid content in salmon parr PL.

  15. The Ecological Coherence of Temperature and Salinity Tolerance Interaction and Pigmentation in a Non-marine Vibrio Isolated from Salar de Atacama.

    Science.gov (United States)

    Gallardo, Karem; Candia, Jonathan E; Remonsellez, Francisco; Escudero, Lorena V; Demergasso, Cecilia S

    2016-01-01

    The occurrence of microorganisms from the Vibrio genus in saline lakes from northern Chile had been evidenced using Numerical Taxonomy decades before and, more recently, by phylogenetic analyses of environmental samples and isolates. Most of the knowledge about this genus came from marine isolates and showed temperature and salinity to be integral agents in shaping the niche of the Vibrio populations. The stress tolerance phenotypes of Vibrio sp. Teb5a1 isolated from Salar de Atacama was investigated. It was able to grow without NaCl and tolerated up to 100 g/L of the salt. Furthermore, it grew between 17° and 49°C (optimum 30°C) in the absence of NaCl, and the range was expanded into cold temperature (4-49°C) in the presence of the salt. Other additional adaptive strategies were observed in response to the osmotic stress: pigment production, identified as the known antibacterial prodigiosin, swimming and swarming motility and synthesis of a polar flagellum. It is possible to infer that environmental congruence might explain the cellular phenotypes observed in Vibrio sp. considering that coupling between temperature and salinity tolerance, the production of antibacterial agents at higher temperatures, flagellation and motility increase the chance of Vibrio sp. to survive in salty environments with high daily temperature swings and UV radiation.

  16. Single nucleotide polymorphism (SNP discovery in duplicated genomes: intron-primed exon-crossing (IPEC as a strategy for avoiding amplification of duplicated loci in Atlantic salmon (Salmo salar and other salmonid fishes

    Directory of Open Access Journals (Sweden)

    Primmer Craig R

    2006-07-01

    Full Text Available Abstract Background Single nucleotide polymorphisms (SNPs represent the most abundant type of DNA variation in the vertebrate genome, and their applications as genetic markers in numerous studies of molecular ecology and conservation of natural populations are emerging. Recent large-scale sequencing projects in several fish species have provided a vast amount of data in public databases, which can be utilized in novel SNP discovery in salmonids. However, the suggested duplicated nature of the salmonid genome may hamper SNP characterization if the primers designed in conserved gene regions amplify multiple loci. Results Here we introduce a new intron-primed exon-crossing (IPEC method in an attempt to overcome this duplication problem, and also evaluate different priming methods for SNP discovery in Atlantic salmon (Salmo salar and other salmonids. A total of 69 loci with differing priming strategies were screened in S. salar, and 27 of these produced ~13 kb of high-quality sequence data consisting of 19 SNPs or indels (one per 680 bp. The SNP frequency and the overall nucleotide diversity (3.99 × 10-4 in S. salar was lower than reported in a majority of other organisms, which may suggest a relative young population history for Atlantic salmon. A subset of primers used in cross-species analyses revealed considerable variation in the SNP frequencies and nucleotide diversities in other salmonids. Conclusion Sequencing success was significantly higher with the new IPEC primers; thus the total number of loci to screen in order to identify one potential polymorphic site was six times less with this new strategy. Given that duplication may hamper SNP discovery in some species, the IPEC method reported here is an alternative way of identifying novel polymorphisms in such cases.

  17. Risk factors for resistance and MDR in community urine isolates: population-level analysis using the NHS Scotland Infection Intelligence Platform.

    Science.gov (United States)

    Malcolm, William; Fletcher, Eilidh; Kavanagh, Kimberley; Deshpande, Ashutosh; Wiuff, Camilla; Marwick, Charis; Bennie, Marion

    2017-10-10

    Urinary tract infections (UTIs) are common. Antibiotic treatment is usually empirical, with the risk of under-treatment of resistant infections. To characterize risk factors for antibiotic-resistant community urine isolates using routine record-linked health data. Within the NHS Scotland Infection Intelligence Platform, national surveillance patient-level data on community urine isolates (January 2012-June 2015) were linked to hospital activity and community prescribing data. Associations between age, gender, comorbidity, care home residence, previous hospitalizations, antibiotic exposure and resistant (any antibiotic) or MDR (≥1 antibiotic from ≥3 categories) urinary isolates were quantified using multivariable logistic regression. Of 40 984 isolates, 28% were susceptible, 45% were resistant and 27% were MDR. Exposure to ≥ 4 different antibiotics in the prior 6 months increased MDR risk (OR 6.81, 95% CI 5.73-8.11). MDR was associated with ≥29 DDD cumulative exposure, in the prior 6 months, for any antibiotic (OR 6.54, 95% CI 5.88-7.27), nitrofurantoin (OR 8.56, 95% CI 6.56-11.18) and trimethoprim (OR 14.61, 95% CI 10.53-20.27). Associations persisted for 10-12 months for nitrofurantoin (OR 2.31, 95% CI 1.93-2.76) and trimethoprim (OR 1.81, 95% CI 1.57-2.09). Increasing age, comorbidity, previous hospitalization and care home residence were independently associated with MDR. For resistant isolates the factors were the same, but with weaker associations. To our knowledge, we have demonstrated, using national capability at scale, the risk of MDR in community urine isolates for the first time and quantified the cumulative and sustained impact of antibiotic exposure. These data will inform the development of decision support tools for UTI treatment.

  18. Population-Level Differentiation in Growth Rates and Leaf Traits in Seedlings of the Neotropical Live Oak Quercus oleoides Grown under Natural and Manipulated Precipitation Regimes

    Directory of Open Access Journals (Sweden)

    Jose A. Ramírez-Valiente

    2017-05-01

    Full Text Available Widely distributed species are normally subjected to spatial heterogeneity in environmental conditions. In sessile organisms like plants, adaptive evolution and phenotypic plasticity of key functional traits are the main mechanisms through which species can respond to environmental heterogeneity and climate change. While extended research has been carried out in temperate species in this regard, there is still limited knowledge as to how species from seasonally-dry tropical climates respond to spatial and temporal variation in environmental conditions. In fact, studies of intraspecific genetically-based differences in functional traits are still largely unknown and studies in these ecosystems have largely focused on in situ comparisons where environmental and genetic effects cannot be differentiated. In this study, we tested for ecotypic differentiation and phenotypic plasticity in leaf economics spectrum (LES traits, water use efficiency and growth rates under natural and manipulated precipitation regimes in a common garden experiment where seedlings of eight populations of the neotropical live oak Quercus oleoides were established. We also examined the extent to which intraspecific trait variation was associated with plant performance under different water availability. Similar to interspecific patterns among seasonally-dry tropical tree species, live oak populations with long and severe dry seasons had higher leaf nitrogen content and growth rates than mesic populations, which is consistent with a “fast” resource-acquisition strategy aimed to maximize carbon uptake during the wet season. Specific leaf area (SLA was the best predictor of plant performance, but contrary to expectations, it was negatively associated with relative and absolute growth rates. This observation was partially explained by the negative association between SLA and area-based photosynthetic rates, which is contrary to LES expectations but similar to other recent

  19. Risk of Adverse Obstetric and Neonatal Outcomes by Maternal Age: Quantifying Individual and Population Level Risk Using Routine UK Maternity Data.

    Directory of Open Access Journals (Sweden)

    Laura Oakley

    Full Text Available The objective of this study was to investigate whether moderately increased maternal age is associated with obstetric and neonatal outcome in a contemporary population, and to consider the possible role of co-morbidities in explaining any increased risk.Secondary analysis of routinely collected data from a large maternity unit in London, UK. Data were available on 51,225 singleton deliveries (≥22 weeks occurring to women aged ≥20 between 2004 and 2012. Modified Poisson regression was used to estimate risk ratios for the association between maternal age and obstetric and neonatal outcome (delivery type, postpartum haemorrhage, stillbirth, low birthweight, preterm birth, small for gestational age, neonatal unit admission, using the reference group 20-24 years. Population attributable fractions were calculated to quantify the population impact.We found an association between increasing maternal age and major postpartum haemorrhage (≥1000ml blood loss (RR 1.36 95% CI 1.18-1.57 for age 25-29 rising to 2.41 95% CI 2.02-2.88 for age ≥40. Similar trends were observed for caesarean delivery, most notably for elective caesareans (RR 1.64 95% CI 1.36-1.96 for age 25-29 rising to 4.94 95% CI 4.09-5.96 for age ≥40. There was evidence that parity modified this association, with a higher prevalence of elective caesarean delivery in older nulliparous women. Women aged ≥35 were at increased risk of low birthweight and preterm birth. We found no evidence that the risk of stillbirth, small for gestational age, or neonatal unit admission differed by maternal age.Our results suggest a gradual increase in the risk of caesarean delivery and postpartum haemorrhage from age 25, persisting after taking into account maternal BMI, hypertension and diabetes. The risk of low birthweight and preterm birth was elevated in women over 35. Further research is needed to understand the reasons behind the high prevalence of elective caesarean delivery in nulliparous

  20. Population-Level Transcriptomic Responses of the Southern Ocean Salp Salpa thompsoni to Environment Variability of the Western Antarctic Peninsula Region

    Science.gov (United States)

    Bucklin, A. C.; Batta Lona, P. G.; Maas, A. E.; O'Neill, R. J.; Wiebe, P. H.

    2015-12-01

    In response to the changing Antarctic climate, the Southern Ocean salp Salpa thompsoni has shown altered patterns of distribution and abundance that are anticipated to have profound impacts on pelagic food webs and ecosystem dynamics. The physiological and molecular processes that underlay ecological function and biogeographical distribution are key to understanding present-day dynamics and predicting future trajectories. This study examined transcriptome-wide patterns of gene expression in relation to biological and physical oceanographic conditions in coastal, shelf and offshore waters of the Western Antarctic Peninsula (WAP) region during austral spring and summer 2011. Based on field observations and collections, seasonal changes in the distribution and abundance of salps of different life stages were associated with differences in water mass structure of the WAP. Our observations are consistent with previous suggestions that bathymetry and currents in Bransfield Strait could generate a retentive cell for an overwintering population of S. thompsoni, which may generate the characteristic salp blooms found throughout the region later in summer. The statistical analysis of transcriptome-wide patterns of gene expression revealed differences among salps collected in different seasons and from different habitats (i.e., coastal versus offshore) in the WAP. Gene expression patterns also clustered by station in austral spring - but not summer - collections, suggesting stronger heterogeneity of environmental conditions. During the summer, differentially expressed genes covered a wider range of functions, including those associated with stress responses. Future research using novel molecular transcriptomic / genomic characterization of S. thompsoni will allow more complete understanding of individual-, population-, and species-level responses to environmental variability and prediction of future dynamics of Southern Ocean food webs and ecosystems.

  1. Impact of Warfarin on Atrial-Fibrillation Outcomes Related to Economic Consumption Patterns: Hospitalization, Cost, and Mortality may be Predictable and Modifiable at the Population Level.

    Science.gov (United States)

    Kim, Michael H; Cai, Qiang; Xu, Liou; Puckrein, Gary A

    2016-09-01

    Warfarin reduces atrial fibrillation (AF)-related strokes and may impact mortality, hospitalizations, and costs. This study investigated the possibility that patterns of warfarin consumption are associated with the frequency of acute events. Annual cost profiles of 9.2 million Medicare beneficiaries with AF were analyzed to identify patterns of benefits consumption from 2000 through 2010. Beneficiaries were divided into five consumption clusters based upon their annual cost profiles, ranging from crisis consumers at the high end to low consumers. Resource-utilization patterns and outcome differences were calculated between AF beneficiaries who received warfarin and those who did not. Propensity score-matched analysis was performed to reduce selection bias. The annual percentages of beneficiaries and expenditures that differentiated each cluster showed stable patterns. Warfarin use influenced consumption patterns and outcomes. The most important financial difference between higher and lower consumers was inpatient cost. AF beneficiaries on warfarin had lower annual cost profiles and had a higher propensity to persist in or migrate to consumption clusters with comparatively small reimbursement claims and lower hospitalization risks. AF beneficiaries not on warfarin had higher cost and mortality. These data signal that a nontrivial portion of acute events (hospitalization and mortality) are amenable to medical intervention (warfarin). When acute events are amenable to medical intervention and occur at a higher frequency because guidelines have not been applied evenly across affected populations, it is appropriate to define those occurrences as disparities associated with systemic failure in evidence-based medicine. Quality-improvement initiatives that reduce therapeutic disparities may result in lower cost and improved outcomes. No funding or sponsorship was received for this study or publication of this article.

  2. Place of death in the population dying from diseases indicative of palliative care need: a cross-national population-level study in 14 countries.

    Science.gov (United States)

    Pivodic, Lara; Pardon, Koen; Morin, Lucas; Addington-Hall, Julia; Miccinesi, Guido; Cardenas-Turanzas, Marylou; Onwuteaka-Philipsen, Bregje; Naylor, Wayne; Ruiz Ramos, Miguel; Van den Block, Lieve; Wilson, Donna M; Loucka, Martin; Csikos, Agnes; Rhee, Yong Joo; Teno, Joan; Deliens, Luc; Houttekier, Dirk; Cohen, Joachim

    2016-01-01

    Studying where people die across countries can serve as an evidence base for health policy on end-of-life care. This study describes the place of death of people who died from diseases indicative of palliative care need in 14 countries, the association of place of death with cause of death, sociodemographic and healthcare availability characteristics in each country and the extent to which these characteristics explain country differences in the place of death. Death certificate data for all deaths in 2008 (age ≥1 year) in Belgium, Canada, the Czech Republic, England, France, Hungary, Italy, Mexico, the Netherlands, New Zealand, South Korea, Spain (Andalusia), the USA and Wales caused by cancer, heart/renal/liver failure, chronic obstructive pulmonary disease, diseases of the nervous system or HIV/AIDS were linked with national or regional healthcare statistics (N=2,220,997). 13% (Canada) to 53% (Mexico) of people died at home and 25% (the Netherlands) to 85% (South Korea) died in hospital. The strength and direction of associations between home death and cause of death, sociodemographic and healthcare availability factors differed between countries. Differences between countries in home versus hospital death were only partly explained by differences in these factors. The large differences between countries in and beyond Europe in the place of death of people in potential need of palliative care are not entirely attributable to sociodemographic characteristics, cause of death or availability of healthcare resources, which suggests that countries' palliative and end-of-life care policies may influence where people die. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

  3. Impact of gestational diabetes mellitus and high maternal weight on the development of diabetes, hypertension and cardiovascular disease: a population-level analysis.

    Science.gov (United States)

    Kaul, P; Savu, A; Nerenberg, K A; Donovan, L E; Chik, C L; Ryan, E A; Johnson, J A

    2015-02-01

    To examine the association between gestational diabetes mellitus (GDM) and high maternal weight and the risk of development of chronic disease. Women with singleton deliveries between April 1999 and March 2010 in Alberta, Canada, were categorized according to pre-pregnancy weight (overweight ≥ 91 kg) and GDM status. Obstetric and neonatal outcomes, as well as the long-term incidence of maternal diabetes, hypertension and cardiovascular disease were examined. Of 240 083 women, 213 765 (89%) had no GDM and were not overweight (reference group), 17 587 (7.3%) were overweight only, 7332 (3%) had GDM only and 1399 (0.6%) had GDM and were overweight. Significant differences in Caesarean section rates, induction rates and birthweight were observed across the four groups. During a median follow-up of 5.3 years, diabetes incidence was 36% in the GDM and overweight, 18.8% in the GDM only, 4.8% in the overweight only and 1.1% in the reference group. With respect to hypertension and cardiovascular disease, the GDM and overweight group had the highest rates (26.8% and 3.1%, respectively) and the reference group had the lowest rates (5.8% and 1.0%, respectively). However, rates were similar in the GDM only (14.9% and 1.9%, respectively) and overweight only groups (14.9% and 1.5%, respectively). Not surprisingly, the presence of both high maternal weight and GDM compounds the risk of developing diabetes. However, the association between overweight alone and GDM alone and hypertension and cardiovascular disease appears similar suggesting a need for effective interventions to manage both these conditions to improve the health of these patients. © 2014 The Authors. Diabetic Medicine © 2014 Diabetes UK.

  4. Epigenetic and conventional regulation is distributed among activators of FLO11 allowing tuning of population-level heterogeneity in its expression.

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    Leah M Octavio

    2009-10-01

    Full Text Available Epigenetic switches encode their state information either locally, often via covalent modification of DNA or histones, or globally, usually in the level of a trans-regulatory factor. Here we examine how the regulation of cis-encoded epigenetic switches controls the extent of heterogeneity in gene expression, which is ultimately tied to phenotypic diversity in a population. We show that two copies of the FLO11 locus in Saccharomyces cerevisiae switch between a silenced and competent promoter state in a random and independent fashion, implying that the molecular event leading to the transition occurs locally at the promoter, in cis. We further quantify the effect of trans regulators both on the slow epigenetic transitions between a silenced and competent promoter state and on the fast promoter transitions associated with conventional regulation of FLO11. We find different classes of regulators affect epigenetic, conventional, or both forms of regulation. Distributing kinetic control of epigenetic silencing and conventional gene activation offers cells flexibility in shaping the distribution of gene expression and phenotype within a population.

  5. A new specific reference gene based on growth hormone gene (GH1) used for detection and relative quantification of Aquadvantage® GM salmon (Salmo salar L.) in food products.

    Science.gov (United States)

    Hafsa, Ahmed Ben; Nabi, Nesrine; Zellama, Mohamed Salem; Said, Khaled; Chaouachi, Maher

    2016-01-01

    Genetic transformation of fish is mainly oriented towards the improvement of growth for the benefit of the aquaculture. Actually, Atlantic salmon (Salmo salar) is the species most transformed to achieve growth rates quite large compared to the wild. To anticipate the presence of contaminations with GM salmon in fish markets and the lack of labeling regulations with a mandatory threshold, the proper methods are needed to test the authenticity of the ingredients. A quantitative real-time polymerase chain reaction (QRT-PCR) method was used in this study. Ct values were obtained and validated using 15 processed food containing salmon. The relative and absolute limits of detection were 0.01% and 0.01 ng/μl of genomic DNA, respectively. Results demonstrate that the developed QRT-PCR method is suitable specifically for identification of S. salar in food ingredients based on the salmon growth hormone gene 1 (GH1). The processes used to develop the specific salmon reference gene case study are intended to serve as a model for performing quantification of Aquadvantage® GM salmon on future genetically modified (GM) fish to be commercialized. Copyright © 2015 Elsevier Ltd. All rights reserved.

  6. The effects of ionic strength on the toxicity of aluminium to Atlantic salmon (Salmo salar under non-steady state chemical conditions

    Directory of Open Access Journals (Sweden)

    Antonio B.S. POLÉO

    2002-02-01

    Full Text Available We have tested the influence of water ionic strength on the toxicity of aluminium in fish by comparing the mortality of Atlantic salmon (Salmo salar parr exposed to Al-rich water with additions of Ca2+ or Na+. The fish were exposed in parallel to Al-rich water (Al 500 μg l-1, pH 5.8 under non-steady state conditions, with and without the addition of one of the two base cations. The amount of Na+ and Ca2+ added to the water was calculated in order to obtain an identical increase in water ionic strength. Fish mortality was dependent on water residence time and whether or not base cations were added to the Al-rich water. In all Al-exposures, the highest mortality was always observed in fish exposed to water with the shortest residence time. Mortality decreased systematically with increasing water residence time through the exposure set-up. The addition of a base cation, Ca2+ or Na+, to the Al-rich water reduced fish mortality significantly compared to the Al-only exposures. Furthermore, increasing ionic strength with Na+ reduced mortality to a larger extent than the corresponding increase in ionic strength by the addition of Ca2+. The variation in mortality between the various aluminium and base cation treatments is discussed in terms of aluminium chemistry, specific mitigating effects of Ca2+ and Na+, and the general importance of water ionic strength. This study clearly demonstrates that Ca2+ does not play an unique role as an ameliorating cation for Al-toxicity in fish under non-steady state chemical conditions. Thus, ionic strength seems to be important, probably for the interaction between aluminium and the gill surface, reducing the possibility for positively charged aluminium species to bind to negatively charged sites.

  7. Nutritional Evaluation of an EPA-DHA Oil from Transgenic Camelina sativa in Feeds for Post-Smolt Atlantic Salmon (Salmo salar L.).

    Science.gov (United States)

    Betancor, Mónica B; Sprague, Matthew; Sayanova, Olga; Usher, Sarah; Metochis, Christoforos; Campbell, Patrick J; Napier, Johnathan A; Tocher, Douglas R

    2016-01-01

    Vegetable oils (VO) are possible substitutes for fish oil in aquafeeds but their use is limited by their lack of omega-3 (n-3) long-chain polyunsaturated fatty acids (LC-PUFA). However, oilseed crops can be modified to produce n-3 LC-PUFA such as eicosapentaenoic (EPA) and docosahexaenoic (DHA) acids, representing a potential option to fill the gap between supply and demand of these important nutrients. Camelina sativa was metabolically engineered to produce a seed oil with around 15% total n-3 LC-PUFA to potentially substitute for fish oil in salmon feeds. Post-smolt Atlantic salmon (Salmo salar) were fed for 11-weeks with one of three experimental diets containing either fish oil (FO), wild-type Camelina oil (WCO) or transgenic Camelina oil (DCO) as added lipid source to evaluate fish performance, nutrient digestibility, tissue n-3 LC-PUFA, and metabolic impact determined by liver transcriptome analysis. The DCO diet did not affect any of the performance or health parameters studied and enhanced apparent digestibility of EPA and DHA compared to the WCO diet. The level of total n-3 LC-PUFA was higher in all the tissues of DCO-fed fish than in WCO-fed fish with levels in liver similar to those in fish fed FO. Endogenous LC-PUFA biosynthetic activity was observed in fish fed both the Camelina oil diets as indicated by the liver transcriptome and levels of intermediate metabolites such as docosapentaenoic acid, with data suggesting that the dietary combination of EPA and DHA inhibited desaturation and elongation activities. Expression of genes involved in phospholipid and triacylglycerol metabolism followed a similar pattern in fish fed DCO and WCO despite the difference in n-3 LC-PUFA contents.

  8. Nutritional Evaluation of an EPA-DHA Oil from Transgenic Camelina sativa in Feeds for Post-Smolt Atlantic Salmon (Salmo salar L..

    Directory of Open Access Journals (Sweden)

    Mónica B Betancor

    Full Text Available Vegetable oils (VO are possible substitutes for fish oil in aquafeeds but their use is limited by their lack of omega-3 (n-3 long-chain polyunsaturated fatty acids (LC-PUFA. However, oilseed crops can be modified to produce n-3 LC-PUFA such as eicosapentaenoic (EPA and docosahexaenoic (DHA acids, representing a potential option to fill the gap between supply and demand of these important nutrients. Camelina sativa was metabolically engineered to produce a seed oil with around 15% total n-3 LC-PUFA to potentially substitute for fish oil in salmon feeds. Post-smolt Atlantic salmon (Salmo salar were fed for 11-weeks with one of three experimental diets containing either fish oil (FO, wild-type Camelina oil (WCO or transgenic Camelina oil (DCO as added lipid source to evaluate fish performance, nutrient digestibility, tissue n-3 LC-PUFA, and metabolic impact determined by liver transcriptome analysis. The DCO diet did not affect any of the performance or health parameters studied and enhanced apparent digestibility of EPA and DHA compared to the WCO diet. The level of total n-3 LC-PUFA was higher in all the tissues of DCO-fed fish than in WCO-fed fish with levels in liver similar to those in fish fed FO. Endogenous LC-PUFA biosynthetic activity was observed in fish fed both the Camelina oil diets as indicated by the liver transcriptome and levels of intermediate metabolites such as docosapentaenoic acid, with data suggesting that the dietary combination of EPA and DHA inhibited desaturation and elongation activities. Expression of genes involved in phospholipid and triacylglycerol metabolism followed a similar pattern in fish fed DCO and WCO despite the difference in n-3 LC-PUFA contents.

  9. Consistent boldness behaviour in early emerging fry of domesticated Atlantic salmon (Salmo salar): Decoupling of behavioural and physiological traits of the proactive stress coping style.

    Science.gov (United States)

    Vaz-Serrano, J; Ruiz-Gomez, M L; Gjøen, H M; Skov, P V; Huntingford, F A; Overli, O; Höglund, E

    2011-06-01

    Individual variation in the way animals cope with stressors has been documented in a number of animal groups. In general, two distinct sets of behavioural and physiological responses to stress have been described: the proactive and the reactive coping styles. Some characteristics of stress coping style seem to be coupled to the time to emerge of fry from spawning redds in natural populations of salmonid fishes. In the present study, behavioural and physiological traits of stress coping styles were compared two and five months after emergence in farmed Atlantic salmon (Salmo salar), using individuals with an early or late time to emerge. Initially, compared to late emerging individuals, early emerging individuals showed a shorter time to resume feeding after transfer to rearing in isolation. Resumption of feeding after isolation was suggested to be related to boldness behaviour, rather than hunger, in the present study. This observation was repeated five months after emergence, demonstrating behavioural consistency over time in this trait. However, in other traits of proactive and reactive stress coping styles, such as social status, resting metabolism or post stress cortisol concentrations, early and late emerging individuals did not differ. Therefore, this study demonstrates that boldness in a novel environment is uncoupled from other traits of the proactive and reactive stress coping styles in farmed salmonids. It is possible that this decoupling is caused by the low competitive environment in which fish were reared. In natural populations of salmonids, however, the higher selection pressure at emergence could select for early emerging individuals with a proactive coping style. Copyright © 2011. Published by Elsevier Inc.

  10. Nutrigenomic profiling of transcriptional processes affected in liver and distal intestine in response to a soybean meal-induced nutritional stress in Atlantic salmon (Salmo salar).

    Science.gov (United States)

    De Santis, Christian; Bartie, Kerry L; Olsen, Rolf E; Taggart, John B; Tocher, Douglas R

    2015-09-01

    The aim of the present study was to generate an experimental model to characterize the nutrigenomic profile of a plant-derived nutritional stress. Atlantic salmon (Salmo salar) was used as the model species. The nutritional stress was induced by inclusion of dietary defatted soybean meal (SBM), as this ingredient had been previously demonstrated to induce enteropathy in the distal intestine and reduce growth in salmon. Triplicate groups of Atlantic salmon were fed concentrations of 0, 100, 200 and 300 g kg(-1) SBM for 12 weeks and reduced growth performance was used as the indicator of nutritional stress. The transcriptome was analyzed in two tissues, liver and distal intestine, with the hypothesis being that the liver transcriptome would be characterized by gene expression responses related to overall growth and health performance, whereas intestinal gene expression would be dominated by specific responses to SBM. A set of 133 genes was differentially expressed in liver including 44 genes in common with the intestinal response. The liver-specific response included up-regulation of genes involved in protein digestion, energy metabolism and immune functions, whereas genes in other metabolic pathways were generally anabolic and down-regulated. These responses may be more related to general nutritional stress than to SBM per se. The transcriptomic profile in the distal intestine was consistent with the enteritis response as described previously. This study provides a comprehensive report on the profiles of liver and distal intestine transcriptomes, specifically highlighting the role of the liver in fish undergoing SBM-induced nutritional stress. Copyright © 2015 Elsevier Inc. All rights reserved.

  11. A review of the likely effects of climate change on anadromous Atlantic salmon Salmo salar and brown trout Salmo trutta, with particular reference to water temperature and flow.

    Science.gov (United States)

    Jonsson, B; Jonsson, N

    2009-12-01

    The present paper reviews the effects of water temperature and flow on migrations, embryonic development, hatching, emergence, growth and life-history traits in light of the ongoing climate change with emphasis on anadromous Atlantic salmon Salmo salar and brown trout Salmo trutta. The expected climate change in the Atlantic is for milder and wetter winters, with more precipitation falling as rain and less as snow, decrease in ice-covered periods and frequent periods with extreme weather. Overall, thermal limits for salmonids are species specific. Scope for activity and growth and optimal temperature for growth increase with temperature to an optimal point before constrain by the oxygen content of the water. The optimal temperature for growth decreases with increasing fish size and varies little among populations within species, whereas the growth efficiency may be locally adapted to the temperature conditions of the home stream during the growth season. Indirectly, temperature influences age and size at smolting through its effect on growth. Time of spawning, egg hatching and emergence of the larvae vary with temperature and selective effects on time of first feeding. Traits such as age at first maturity, longevity and fecundity decrease with increasing temperature whilst egg size increases with temperature. Water flow influences the accessibility of rivers for returning adults and speed of both upstream and downstream migration. Extremes in water flow and temperature can decrease recruitment and survival. There is reason to expect a northward movement of the thermal niche of anadromous salmonids with decreased production and population extinction in the southern part of the distribution areas, migrations earlier in the season, later spawning, younger age at smolting and sexual maturity and increased disease susceptibility and mortality. Future research challenges are summarized at the end of the paper.

  12. Mineralization of the vertebral bodies in Atlantic salmon (Salmo salar L.) is initiated segmentally in the form of hydroxyapatite crystal accretions in the notochord sheath

    Science.gov (United States)

    Wang, Shou; Kryvi, Harald; Grotmol, Sindre; Wargelius, Anna; Krossøy, Christel; Epple, Mattias; Neues, Frank; Furmanek, Tomasz; Totland, Geir K

    2013-01-01

    We performed a sequential morphological and molecular biological study of the development of the vertebral bodies in Atlantic salmon (Salmo salar L.). Mineralization starts in separate bony elements which fuse to form complete segmental rings within the notochord sheath. The nucleation and growth of hydroxyapatite crystals in both the lamellar type II collagen matrix of the notochord sheath and the lamellar type I collagen matrix derived from the sclerotome, were highly similar. In both matrices the hydroxyapatite crystals nucleate and accrete on the surface of the collagen fibrils rather than inside the fibrils, a process that may be controlled by a template imposed by the collagen fibrils. Apatite crystal growth starts with the formation of small plate-like structures, about 5 nm thick, that gradually grow and aggregate to form extensive multi-branched crystal arborizations, resembling dendritic growth. The hydroxyapatite crystals are always oriented parallel to the long axis of the collagen fibrils, and the lamellar collagen matrices provide oriented support for crystal growth. We demonstrate here for the first time by means of synchroton radiation based on X-ray diffraction that the chordacentra contain hydroxyapatite. We employed quantitative real-time PCR to study the expression of key signalling molecule transcripts expressed in the cellular core of the notochord. The results indicate that the notochord not only produces and maintains the notochord sheath but also expresses factors known to regulate skeletogenesis: sonic hedgehog (shh), indian hedgehog homolog b (ihhb), parathyroid hormone 1 receptor (pth1r) and transforming growth factor beta 1 (tgfb1). In conclusion, our study provides evidence for the process of vertebral body development in teleost fishes, which is initially orchestrated by the notochord. PMID:23711083

  13. Detection of vitellogenin and zona radiata protein expressions in surface mucus of immature juvenile Atlantic salmon (Salmo salar) exposed to waterborne nonylphenol

    Energy Technology Data Exchange (ETDEWEB)

    Meucci, Valentina [Department of Veterinary Clinics, Section of Pharmacology and Toxicology, University of Pisa, V. le delle Piagge 2, 56124 Pisa (Italy); Arukwe, Augustine [Department of Biology, Norwegian University of Science and Technology (NTNU), Hoyskoleringen 5, 7491 Trondheim (Norway)]. E-mail: arukwe@bio.ntnu.no

    2005-06-01

    Induction of blood plasma vitellogenin (Vtg) and zona radiata proteins (Zr-proteins) in male and juvenile of oviparous vertebrates was proposed and shown to be sensitive biomarkers for exposure to estrogen mimic. The time- and dose-dependent expression of Vtg and Zr-proteins in nonylphenol (NP) exposed juvenile Atlantic salmon (Salmo salar) is reported. Fish were exposed continuously to waterborne nonylphenol at 5, 15 and 50 {mu}g/L. Blood and surface mucus samples were collected after 3 and 7 days post-exposure. Nonylphenol-induced plasma and surface mucus levels of Vtg and Zr-protein were analysed using immunochemical methods (Western blot and enzyme-linked immunosorbent assay; ELISA). Both Vtg and Zr-protein levels in plasma and surface mucus showed similar and parallel nonylphenol-induced expression patterns after waterborne nonylphenol exposure and in a concentration- and time-dependent manner. Zr-proteins were significantly induced at the lowest concentration of nonylphenol after 3 and 7 days of exposure both in plasma and in surface mucus. We conclude that the detection of Vtg and Zr-proteins directly in the surface mucus of fish, and the correlation of these values with plasma protein biomarker values in xenoestrogen-treated fish represents a sensitive non-invasive system for the detection of these known endocrine disruptor biomarkers. The demonstration of detectable Vtg and Zr-protein levels from surface mucus is a potential biomarker for estrogenic compounds, and their presence should be considered as an improvement in the methods for detection of endocrine disrupting chemicals (EDCs) and related pollutants in the environment.

  14. An EST-based approach for identifying genes expressed in the intestine and gills of pre-smolt Atlantic salmon (Salmo salar

    Directory of Open Access Journals (Sweden)

    Adzhubei Alexei

    2005-12-01

    Full Text Available Abstract Background The Atlantic salmon is an important aquaculture species and a very interesting species biologically, since it spawns in fresh water and develops through several stages before becoming a smolt, the stage at which it migrates to the sea to feed. The dramatic change of habitat requires physiological, morphological and behavioural changes to prepare the salmon for its new environment. These changes are called the parr-smolt transformation or smoltification, and pre-adapt the salmon for survival and growth in the marine environment. The development of hypo-osmotic regulatory ability plays an important part in facilitating the transition from rivers to the sea. The physiological mechanisms behind the developmental changes are largely unknown. An understanding of the transformation process will be vital to the future of the aquaculture industry. A knowledge of which genes are expressed prior to the smoltification process is an important basis for further studies. Results In all, 2974 unique sequences, consisting of 779 contigs and 2195 singlets, were generated for Atlantic salmon from two cDNA libraries constructed from the gills and the intestine, accession numbers [Genbank: CK877169-CK879929, CK884015-CK886537 and CN181112-CN181464]. Nearly 50% of the sequences were assigned putative functions because they showed similarity to known genes, mostly from other species, in one or more of the databases used. The Swiss-Prot database returned significant hits for 1005 sequences. These could be assigned predicted gene products, and 967 were annotated using Gene Ontology (GO terms for molecular function, biological process and/or cellular component, employing an annotation transfer procedure. Conclusion This paper describes the construction of two cDNA libraries from pre-smolt Atlantic salmon (Salmo salar and the subsequent EST sequencing, clustering and assigning of putative function to 1005 genes expressed in the gills and/or intestine.

  15. The kinetics of CD4+ and CD8+ T-cell gene expression correlate with protection in Atlantic salmon (Salmo salar L) vaccinated against infectious pancreatic necrosis.

    Science.gov (United States)

    Munang'andu, Hetron Mweemba; Fredriksen, Børge Nilsen; Mutoloki, Stephen; Dalmo, Roy Ambli; Evensen, Oystein

    2013-04-08

    Infectious pancreatic necrosis virus (IPNV) is a highly contagious disease causing high mortalities in juvenile salmonids. Lack of correlation between neutralizing antibodies and infecting virus suggests a likelihood of involvement of the cellular mediated immune response in vaccine protection. To elucidate the kinetics of CD4 and CD8 T-cells responses in vaccine protection, Atlantic salmon (Salmo salar L) were vaccinated with a high antigen (HiAg) or low antigen (LoAg) dose vaccine and challenged by cohabitation using a highly virulent Norwegian Sp strain. Analysis of T-cell gene expression in lymphoid organs (headkidney and spleen) showed that GATA-3 was positively correlated with increase in antibody levels when T-bet was low. Conversely, T-bet and FoxP3 were positively correlated with viral infection and negatively correlated with increase in antibody levels. Among the CD8+ T cell genes, expression of eomes and CD8α were positively correlated with increase in viral copy numbers and negatively correlated with increase in antibody levels. Up-regulation of granzyme A was highly correlated with increase in viral copy numbers in the LoAg and control groups indicating that this gene could save as a diagnostic marker of acute infection for IPNV during acute infection. In contrast, its down regulation in the HiAg which had low viral copy numbers corresponded with high antibody levels. Overall, these data show that the kinetics of CD4 and CD8 T-cell genes expression follow the same pattern as that observed in higher vertebrates. These findings suggest that functional signatures of the cellular mediated immune response could be evolutionary conserved across the vertebrate taxa and that they can effectively be used to monitor vaccine protection and infection progression of IPNV in Atlantic salmon. Copyright © 2013 Elsevier Ltd. All rights reserved.

  16. Alginate Microencapsulation for Oral Immunisation of Finfish: Release Characteristics, Ex Vivo Intestinal Uptake and In Vivo Administration in Atlantic Salmon, Salmo salar L.

    Science.gov (United States)

    Ghosh, Bikramjit; Nowak, Barbara F; Bridle, Andrew R

    2015-12-01

    This study examined the feasibility of alginate microcapsules manufactured using a low-impact technology and reagents to protect orally delivered immunogens for use as immunoprophylactics for fish. Physical characteristics and protein release kinetics of the microcapsules were examined at different pH and temperature levels using a microencapsulated model protein, bovine serum albumin (BSA). Impact of the microencapsulation process on contents was determined by analysing change in bioactivity of microencapsulated lysozyme. Feasibility of the method for oral immunoprophylaxis of finfish was assessed using FITC-labelled microcapsules. These were applied to distal intestinal explants of Atlantic salmon (Salmo salar) to investigate uptake ex vivo. Systemic distribution of microcapsules was investigated by oral administration of FITC-labelled microcapsules to Atlantic salmon fry by incorporating into feed. The microcapsules produced were structurally robust and retained surface integrity, with a modal size distribution of 250-750 nm and a tendency to aggregate. Entrapment efficiency of microencapsulation was 51.2 % for BSA and 43.2 % in the case of lysozyme. Microcapsules demonstrated controlled release of protein, which increased with increasing pH or temperature, and the process had no significant negative effect on bioactivity of lysozyme. Uptake of fluorescent-labelled microcapsules was clearly demonstrated by intestinal explants over a 24-h period. Evidence of microcapsules was found in the intestine, spleen, kidney and liver of fry following oral administration. Amenability of the microcapsules to intestinal uptake and distribution reinforced the strong potential for use of this microencapsulation method in oral immunoprophylaxis of finfish using sensitive immunogenic substances.

  17. Comparative study of pineal clock gene and AANAT2 expression in relation to melatonin synthesis in Atlantic salmon (Salmo salar) and European seabass (Dicentrarchus labrax).

    Science.gov (United States)

    McStay, Elsbeth; Migaud, Herve; Vera, Luisa Maria; Sánchez-Vázquez, Francisco Javier; Davie, Andrew

    2014-03-01

    The photoreceptive teleost pineal is considered to be essential to the generation, synchronisation and maintenance of biological rhythms, primarily via melatonin release. The role of internal (circadian clock) and external (light) signals controlling melatonin production in the fish pineal differs between species, yet the reasons underpinning this remain largely unknown. Whilst in salmonids, pineal melatonin is apparently regulated directly by light, in all other studied teleosts, rhythmic melatonin production persists endogenously under the regulation of clock gene expression. To better understand the role of clocks in teleost pineals, this study aimed to characterise the expression of selected clock genes in vitro under different photoperiodic conditions in comparison to in vivo in both Atlantic salmon (Salmo salar) and in European seabass (Dicentrarchus labrax) (in vitro 12L:12D), a species known to display endogenous rhythmic melatonin synthesis. Results revealed no rhythmic clock gene (Clock, Period 1 &2) expression in Atlantic salmon or European seabass (Clock and Period 1) pineal in vitro. However rhythmic expression of Cryptochrome 2 and Period 1 in the Atlantic salmon pineal was observed in vivo, which infers extra-pineal regulation of clocks in this species. No rhythmic arylalkylamine N-acetyltransferase 2 (Aanat2) expression was observed in the Atlantic salmon yet in the European seabass, circadian Aanat2 expression was observed. Subsequent in silico analysis of available Aanat2 genomic sequences reveals that Atlantic salmon Aanat2 promoter sequences do not contain similar regulatory architecture as present in European seabass, and previously described in other teleosts which alludes to a loss in functional connection in the pathway. Copyright © 2013 Elsevier Inc. All rights reserved.

  18. Effect of nutritional status and sampling intensity on recovery after dorsal aorta cannulation in free-swimming Atlantic salmon (Salmo salar L.).

    Science.gov (United States)

    Djordjevic, B; Kristensen, T; Øverli, Ø; Rosseland, B O; Kiessling, A

    2012-02-01

    Recovery from implantation of a cannula in the dorsal aorta (DA) of Atlantic salmon (Salmo salar) was studied in relation to nutritional status and sampling intensity. The incentive for the study was the inconsistency between published reports and our own experience of recovery and longevity of fish exposed to this protocol. In two studies using starved fish, blood (0.3 ml) was sampled 0, 1 and 24 h after DA-cannulation, and thereafter at 48 and 72 h and thereafter once weekly for four weeks. In a third study using fed fish, four consecutive samples (0, 3, 6 and 12 h after a meal) were obtained twice a week over a four-week period. All fish displayed a sharp increase in pCO(2) and haematocrit (Hct) during surgery, followed by a marked raise in cortisol, glucose, sodium and potassium (1 h). pCO(2), pH and Hct approached baseline levels as early as the 1 h post-surgery sample, while this was not the case for cortisol and electrolytes before the 24 h post-surgery sample. Glucose did not display any significant changes post surgery. From then on, all variables displayed minor but non-significant (P > 0.05) changes indicating a steady state close to baseline values for unstressed fish. This pattern was independent of sampling procedure, i.e. repeated single or multiple samples and thus volume of blood removed. Nutritional status (fed vs. starved) did not affect post-surgical recovery pattern. Only K(+) and Hct displayed consistent and significant post-prandial patterns. We found marked differences between baseline level of cannulated fish and uncannulated control fish, in pH, K(+) and Hct indicating that cannulation may be the preferred method to obtain representative resting values in fish.

  19. Migratory patterns of hatchery and stream-reared Atlantic salmon Salmo salar smolts in the Connecticut River, U.S.A.

    Science.gov (United States)

    McCormick, S D; Haro, A; Lerner, D T; O'Dea, M F; Regish, A M

    2014-10-01

    The timing of downstream migration and detection rates of hatchery-reared Atlantic salmon Salmo salar smolts and stream-reared smolts (stocked 2 years earlier as fry) were examined in the Connecticut River (U.S.A.) using passive integrated transponder (PIT) tags implanted into fish and then detected at a downstream fish bypass collection facility at Turners Falls, MA (river length 192 km). In two successive years, hatchery-reared smolts were released in mid-April and early May at two sites: the West River (river length 241 km) or the Passumpsic (river length 450 km). Hatchery-reared smolts released higher in the catchment arrived 7 to 14 days later and had significantly lower detection rates than smolts stocked lower in the catchment. Hatchery-reared smolts released 3 weeks apart at the same location were detected downstream at similar times, indicating that early-release smolts had a lower average speed after release and longer residence time. The size and gill Na(+) /K(+) -ATPase (NKA) activity of smolts at the time of release were significantly greater for detected fish (those that survived and migrated) than for those that were not detected. Stream-reared pre-smolts (>11·5 cm) from four tributaries (length 261-551 km) were tagged in autumn and detected during smolt migration the following spring. Stream-reared smolts higher in the catchment arrived later and had significantly lower detection rates. The results indicate that both hatchery and stream-reared smolts from the upper catchment will arrive at the mouth of the river later and experience higher overall mortality than fish from lower reaches, and that both size and gill NKA activity are related to survival during downstream migration. © 2014 The Fisheries Society of the British Isles.

  20. Weighing the Oligocene extensional event in the Salar de Atacama Basin by analysis of depth-converted sections and geophysical data.

    Science.gov (United States)

    Bascunan, S. A.; Maksymowicz, A.; Martínez, F.; Becerra, J.; Rubilar, J. F.; Arriagada, C.; Peña Gomez, M. A.; Gómez, I.

    2016-12-01

    Multiple studies of industry seismic lines across the Salar de Atacama Basin, in the Central Andes of northern Chile (22°-24°S), have led to opposite interpretations regarding its internal architecture, particularly for the Cenozoic successions. These differences can be attributed to the yet uncertain stratigraphy of the 5425 m-deep Toconao-1 well, its relation to outcrops around the El Bordo Escarpment, the tie between the well and the seismic lines, and the lack of a depth conversion of these lines. An analysis of these data allows for the proper location in the depth domain of the most important reflectors found in line Z-1G010, which intersects the borehole. The vertical seismic profile and the density log show that the most significant change in lithological properties occurs at ca. 1 s TWT (1580 m), at the transition from mainly evaporitic deposits to more clastic units, presumably belonging to the Loma Amarilla Formation. This modification in velocity and density can be seen in the seismic line as a major west-dipping surface, dubbed the San Pedro Reflector (SPR). The use of 3D software and the depth conversion allow following the SPR along most of the basin. The surface shows an east-to-west, south-to-north increase in depth, reaching a maximum close to 8 km. The geometry of the surface closely follows the trend of the El Bordo Escarpment. Based on paleomagnetic data, recent mapping and geochronology data, the reflector is estimated to have formed during the Oligocene. Additional extensional features confirm its origin due to small-scale collapse of the Cordillera de Domeyko after the Eocene Incaic Event, after which the deformation front migrated eastwards, thus explaining the presence of extension and compression along the margin at the same time. This change in stress state also affected other parts of the range, such as the Calama Basin.

  1. Influence of stocking density on growth, body composition and energy budget of Atlantic salmon Salmo salar L. in recirculating aquaculture systems

    Science.gov (United States)

    Liu, Baoliang; Liu, Ying; Liu, Ziyi; Qiu, Denggao; Sun, Guoxiang; Li, Xian

    2014-09-01

    Atlantic salmon Salmo salar were reared at four stocking densities—high density D 1 (final density ˜39 kg/m3), medium densities D 2 (˜29 kg/m3) and D 3 (˜19 kg/m3), and low density D 4 (˜12 kg/m3)—for 40 days to investigate the effect of stocking density on their growth performance, body composition and energy budgets. Stocking density did not significantly affect specific growth rate in terms of weight (SGRw) but did affect specific growth rate in terms of energy (SGRe). Stocking density significantly influenced the ration level (RLw and RLe), feed conversion ratio (FCRw and FCRe) and apparent digestibility rate (ADR). Ration level and FCRw tended to increase with increasing density. Fish at the highest density D 1 and lowest density D 4 showed lower FCRe and higher ADR than at medium densities. Stocking density significantly affected protein and energy contents of the body but did not affect its moisture, lipid, or ash contents. The expenditure of energy for metabolism in the low-density and high-density groups was lower than that in the medium-density groups. Stocking density affected energy utilization from the feces but had no effect on excretion rate. The greater energy allocation to growth at high density and low density may be attributed to reduced metabolic rate and increased apparent digestibility rate. These findings provide information that will assist selection of suitable stocking densities in the Atlantic-salmon-farming industry.

  2. Atlantic salmon (Salmo salar) muscle precursor cells differentiate into osteoblasts in vitro: polyunsaturated fatty acids and hyperthermia influence gene expression and differentiation.

    Science.gov (United States)

    Ytteborg, Elisabeth; Vegusdal, Anne; Witten, P Eckhard; Berge, Gerd Marit; Takle, Harald; Østbye, Tone-Kari; Ruyter, Bente

    2010-02-01

    The formation and mineralisation of bone are two critical processes in fast-growing Atlantic salmon (Salmo salar). The mechanisms of these processes, however, have not been described in detail. Thus, in vitro systems that allow the study of factors that influence bone formation in farmed Atlantic salmon are highly warranted. We describe here a method by which unspecialized primary cells from salmon white muscle can differentiate to osteoblasts in vitro. We have subsequently used the differentiated cells as a model system to study the effects of two factors that influence bone formation in Atlantic salmon under commercial farming conditions, namely polyunsaturated fatty acids, PUFAs, and temperature. Muscle precursor cells changed their morphology from triangular or spindle-shaped cells to polygonal or cubical cells after 3 weeks in osteogenic medium. In addition, gene expression studies showed that marker genes for osteoblastogenesis; alp, col1a1, osteocalcin, bmp2 and bmp4 increased after 3 weeks of incubation in osteogenic media showing that these cells have differentiated to osteoblasts at this stage. Adding CLA or DHA to the osteoblast media resulted in a reduced PGE(2) production and increased expression of osteocalcin. Further, temperature studies showed that differentiating osteoblasts are highly sensitive to increased incubation temperature at early stages of differentiation. Our studies show that unspecialized precursor cells isolated from salmon muscle tissue can be caused to differentiate to osteoblasts in vitro. Furthermore, this model system appears to be suitable for the study of osteoblast biology in vitro. 2009 Elsevier B.V. All rights reserved.

  3. The role of gender inequities in women's access to reproductive health care: a population-level study of Namibia, Kenya, Nepal, and India

    Directory of Open Access Journals (Sweden)

    Namasivayam A

    2012-07-01

    Full Text Available Amrita Namasivayam,1 Donatus C Osuorah,2 Rahman Syed,3 Diddy Antai3,41Department of Public Health, Division of Global Health (IHCAR, Karolinska Institute, Stockholm, Sweden; 2Department of Pediatrics, Nnamdi Azikiwe University Teaching Hospital, Nnewi, Anambra, Nigeria; 3Department of Public Health, Division of Social Medicine, Karolinska Institute, Stockholm, Sweden; 4Division of Global Health and Inequalities, The Angels Trust, Abuja, NigeriaBackground: The role of gender inequities in explaining women's access to reproductive health care was examined in four countries (two sub-Saharan African and two South Asian countries. The extent of gender inequities varies across and within countries, and is rooted in the different cultural practices and gender norms within these different countries, and differences in the status and autonomy of women.Methods: Demographic and Health Survey data from women aged 15–49 years within these countries were analyzed with multivariate logistic regression analysis to examine the role of multidimensional characteristics of gender inequities, operationalized as access to skilled antenatal care, tetanus toxoid injection during pregnancy, and access to skilled antenatal care.Results: Significant associations were found between several dimensions of gender inequities (with the exception of decision-making autonomy and reported use of maternal reproductive health care services. Several pathways of influence between the outcome and exposure variables were also identified.Conclusion: Dimensions of gender inequities (with the exception of decision-making autonomy differentially influenced woman's use of reproductive health care services, thus highlighting the urgent need for concerted and sustained efforts to change these harmful traditional values if several of these countries are to meet Millennium Development Goal-5.Keywords: women, gender inequities, reproductive health care, Namibia, Kenya, Nepal, India

  4. Energetic demands of immature sea otters from birth to weaning: implications for maternal costs, reproductive behavior and population-level trends.

    Science.gov (United States)

    Thometz, N M; Tinker, M T; Staedler, M M; Mayer, K A; Williams, T M

    2014-06-15

    Sea otters (Enhydra lutris) have the highest mass-specific metabolic rate of any marine mammal, which is superimposed on the inherently high costs of reproduction and lactation in adult females. These combined energetic demands have been implicated in the poor body condition and increased mortality of female sea otters nearing the end of lactation along the central California coast. However, the cost of lactation is unknown and currently cannot be directly measured for this marine species in the wild. Here, we quantified the energetic demands of immature sea otters across five developmental stages as a means of assessing the underlying energetic challenges associated with pup rearing that may contribute to poor maternal condition. Activity-specific metabolic rates, daily activity budgets and field metabolic rates (FMR) were determined for each developmental stage. Mean FMR of pre-molt pups was 2.29 ± 0.81 MJ day(-1) and increased to 6.16 ± 2.46 and 7.41 ± 3.17 MJ day(-1) in post-molt pups and dependent immature animals, respectively. Consequently, daily energy demands of adult females increase 17% by 3 weeks postpartum and continue increasing to 96% above pre-pregnancy levels by the average age of weaning. Our results suggest that the energetics of pup rearing superimposed on small body size, marine living and limited on-board energetic reserves conspire to make female sea otters exceptionally vulnerable to energetic shortfalls. By controlling individual fitness, maternal behavior and pup provisioning strategies, this underlying metabolic challenge appears to be a major factor influencing current population trends in southern sea otters (Enhydra lutris nereis). © 2014. Published by The Company of Biologists Ltd.

  5. Energetic demands of immature sea otters from birth to weaning: implications for maternal costs, reproductive behavior and population-level trends

    Science.gov (United States)

    Thometz, N.M.; Tinker, M.T.; Staedler, M.M.; Mayer, K.A.; Williams, T.M.

    2014-01-01

    Sea otters (Enhydra lutris) have the highest mass-specific metabolic rate of any marine mammal, which is superimposed on the inherently high costs of reproduction and lactation in adult females. These combined energetic demands have been implicated in the poor body condition and increased mortality of female sea otters nearing the end of lactation along the central California coast. However, the cost of lactation is unknown and currently cannot be directly measured for this marine species in the wild. Here, we quantified the energetic demands of immature sea otters across five developmental stages as a means of assessing the underlying energetic challenges associated with pup rearing that may contribute to poor maternal condition. Activity-specific metabolic rates, daily activity budgets and field metabolic rates (FMR) were determined for each developmental stage. Mean FMR of pre-molt pups was 2.29±0.81 MJ day−1 and increased to 6.16±2.46 and 7.41±3.17 MJ day−1 in post-molt pups and dependent immature animals, respectively. Consequently, daily energy demands of adult females increase 17% by 3 weeks postpartum and continue increasing to 96% above pre-pregnancy levels by the average age of weaning. Our results suggest that the energetics of pup rearing superimposed on small body size, marine living and limited on-board energetic reserves conspire to make female sea otters exceptionally vulnerable to energetic shortfalls. By controlling individual fitness, maternal behavior and pup provisioning strategies, this underlying metabolic challenge appears to be a major factor influencing current population trends in southern sea otters (Enhydra lutris nereis).

  6. Determining the need and utilization of radiotherapy in cancers of the breast, cervix, lung, prostate and rectum: A population level study.

    Science.gov (United States)

    Shack, Lorraine; Lu, Shuang; Weeks, Lee-Anne; Craighead, Peter; Kerba, Marc

    2017-01-01

    Determining the appropriate rate of radiotherapy (RT) utilization is important for health care planning and resource allocation. The difference between the observed and the appropriate RT rate is influenced by the choice of a criterion based benchmarking (CBB) or evidence-based estimates (EBEST) measure. Our primary objective was to determine the utilization of radiotherapy for cancers of the breast (B), cervix (C), lung (L), prostate (P) and rectum (R) in Alberta (AB) Canada and to compare the observed RT rates to estimates of need derived from the criterion based benchmarking (CBB) and evidence-based estimates (EBEST). All incident cases of B,C,L,P and R cancers diagnosed in AB during 2004-8 (prior to the decentralization of provincial RT capacity) were identified from the Alberta Cancer Registry. Patients receiving RT within one year (RT-1y) of diagnosis were identified and the proportion receiving RT-1y was then calculated. Factors associated with RT utilization were analysed by region. Estimates of the need for RT were derived from CBB and EBEST methods in the literature. A total of n=68,164 cancer cases were identified from the ACR. RT-1y rates (95% C.I.) were B: 51.5% (50.1-52.9), C: 48.9% (43.8-54.0), L: 37.1% (35.4-38.8), P: 26.9% (25.1-28.7) and R: 39.3% (36.5-42.1). Observed rates of RT in AB were lower than estimates derived using the CBB and EBEST estimates. Shortfalls varied across cancer sites according to whether a CBB or EBEST estimate was used ranging from a low of -0.3% in cancer of the cervix to a high of 30.3% in rectal cancer. RT shortfalls exist in the utilization of RT in AB, Canada despite centralized cancer care and a publically funded health care system. Decisions to address shortfalls need to be mindful of how model selection can impact on findings. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  7. Using data from patient interactions in primary care for population level chronic disease surveillance: The Sentinel Practices Data Sourcing (SPDS) project.

    Science.gov (United States)

    Ghosh, Abhijeet; Charlton, Karen E; Girdo, Lisa; Batterham, Marijka

    2014-06-05

    monitoring of chronic disease prevalence and its associated risk factors at the local level. Selection of sentinel sites that are representative of the population being served will facilitate an accurate and region-specific system for the purpose of population health planning at the primary care level.

  8. Potential Population-Level Nutritional Impact of Replacing Whole and Reduced-Fat Milk With Low-Fat and Skim Milk Among US Children Aged 2?19?Years

    OpenAIRE

    Rehm, Colin D; Drewnowski, Adam; Monsivais, Pablo

    2015-01-01

    Objective Dietary guidance emphasizes plain low-fat and skim milk over whole, reduced-fat, and flavored milk (milk eligible for replacement [MER]). The objective of this study was to evaluate the population-level impact of such a change on energy, macronutrient and nutrient intakes, and diet cost. Design Cross-sectional modeling study. Setting Data from the 2001?2002 and 2003?2004 National Health and Nutrition Examination Survey. Participants A total of 8,112 children aged 2?19?years. Main Ou...

  9. Prevention and control of dental caries and periodontal diseases at individual and population level: consensus report of group 3 of joint EFP/ORCA workshop on the boundaries between caries and periodontal diseases.

    Science.gov (United States)

    Jepsen, Søren; Blanco, Juan; Buchalla, Wolfgang; Carvalho, Joana C; Dietrich, Thomas; Dörfer, Christof; Eaton, Kenneth A; Figuero, Elena; Frencken, Jo E; Graziani, Filippo; Higham, Susan M; Kocher, Thomas; Maltz, Marisa; Ortiz-Vigon, Alberto; Schmoeckel, Julian; Sculean, Anton; Tenuta, Livia M A; van der Veen, Monique H; Machiulskiene, Vita

    2017-03-01

    The non-communicable diseases dental caries and periodontal diseases pose an enormous burden on mankind. The dental biofilm is a major biological determinant common to the development of both diseases, and they share common risk factors and social determinants, important for their prevention and control. The remit of this working group was to review the current state of knowledge on epidemiology, socio-behavioural aspects as well as plaque control with regard to dental caries and periodontal diseases. Discussions were informed by three systematic reviews on (i) the global burden of dental caries and periodontitis; (ii) socio-behavioural aspects in the prevention and control of dental caries and periodontal diseases at an individual and population level; and (iii) mechanical and chemical plaque control in the simultaneous management of gingivitis and dental caries. This consensus report is based on the outcomes of these systematic reviews and on expert opinion of the participants. Key findings included the following: (i) prevalence and experience of dental caries has decreased in many regions in all age groups over the last three decades; however, not all societal groups have benefitted equally from this decline; (ii) although some studies have indicated a possible decline in periodontitis prevalence, there is insufficient evidence to conclude that prevalence has changed over recent decades; (iii) because of global population growth and increased tooth retention, the number of people affected by dental caries and periodontitis has grown substantially, increasing the total burden of these diseases globally (by 37% for untreated caries and by 67% for severe periodontitis) as estimated between 1990 and 2013, with high global economic impact; (iv) there is robust evidence for an association of low socio-economic status with a higher risk of having dental caries/caries experience and also with higher prevalence of periodontitis; (v) the most important behavioural factor

  10. Cardiac pathological changes of Atlantic salmon (Salmo salar L.) affected with heart and skeletal muscle inflammation (HSMI)

    DEFF Research Database (Denmark)

    Yousaf, Muhammad Naveed; Koppang, Erling Olaf; Skjødt, Karsten

    2012-01-01

    Heart and skeletal muscle inflammation (HSMI) is a disease of marine farmed Atlantic salmon where the pathological changes associated with the disease involve necrosis and an infiltration of inflammatory cells into different regions of the heart and skeletal muscle. The aim of this work...... was to characterize cardiac changes and inflammatory cell types associated with a clinical HSMI outbreak in Atlantic salmon using immunohistochemistry. Different immune cells and cardiac tissue responses associated with the disease were identified using different markers. The spectrum of inflammatory cells associated...... immunostaining was observed for major histocompatibility complex (MHC) class II in HSMI hearts. Although low in number, a few positive cells in diseased hearts were detected using the mature myeloid cell line granulocytes/monocytes antibody indicating more positive cells in diseased than non-diseased hearts...

  11. PCR survey for Paramoeba perurans in fauna, environmental samples and fish associated with marine farming sites for Atlantic salmon (Salmo salar L.).

    Science.gov (United States)

    Hellebø, A; Stene, A; Aspehaug, V

    2017-05-01

    Amoebic gill disease (AGD) caused by the amoeba Paramoeba perurans is an increasing problem in Atlantic salmon aquaculture. In the present PCR survey, the focus was to identify reservoir species or environmental samples where P. perurans could be present throughout the year, regardless of the infection status in farmed Atlantic salmon. A total of 1200 samples were collected at or in the proximity to farming sites with AGD, or with history of AGD, and analysed for the presence of P. perurans. No results supported biofouling organisms, salmon lice, biofilm or sediment to maintain P. perurans. However, during clinical AGD in Atlantic salmon, the amoeba were detected in several samples, including water, biofilm, plankton, several filter feeders and wild fish. It is likely that some of these samples were positive as a result of the continuous exposure through water. Positive wild fish may contribute to the spread of P. perurans. Cleaner fish tested positive for P. perurans when salmon tested negative, indicating that they may withhold the amoeba longer than salmon. The results demonstrate the high infection pressure produced from an AGD-afflicted Atlantic salmon population and thus the importance of early intervention to reduce infection pressure and horizontal spread of P. perurans within farms. © 2016 John Wiley & Sons Ltd.

  12. Towards a Long-Term Strategy for Voluntary-Based Internal Radiation Contamination Monitoring: A Population-Level Analysis of Monitoring Prevalence and Factors Associated with Monitoring Participation Behavior in Fukushima, Japan

    National Research Council Canada - National Science Library

    Shuhei Nomura; Masaharu Tsubokura; Akihiko Ozaki; Michio Murakami; Susan Hodgson; Marta Blangiardo; Yoshitaka Nishikawa; Tomohiro Morita; Tomoyoshi Oikawa

    2017-01-01

    Following Japan’s 2011 Fukushima nuclear incident, we assessed voluntary-based monitoring behavior in Minamisoma City-located 10-40 km from the Fukushima nuclear plant-to inform future monitoring strategies...

  13. The dietary replacement of marine ingredients by terrestrial animal and plant alternatives modulates the antiviral immune response of Atlantic salmon (Salmo salar).

    Science.gov (United States)

    Caballero-Solares, Albert; Hall, Jennifer R; Xue, Xi; Eslamloo, Khalil; Taylor, Richard G; Parrish, Christopher C; Rise, Matthew L

    2017-05-01

    The effects of replacing marine ingredients by terrestrial ingredients on the health of Atlantic salmon (Salmo salar) are poorly understood. During a 14-week trial, Atlantic salmon fed a fish meal-fish oil based diet (MAR) showed similar growth performance to others fed a plant protein/vegetable oil based diet (VEG), whereas poorer performance was observed in those fed an animal by-product meal/vegetable oil based diet (ABP). At the end of the trial, salmon were injected with either phosphate-buffered saline (PBS) or the viral mimic polyriboinosinic polyribocytidylic acid (pIC) and sampled for head kidney RNA after 24 h. The levels of 27 immune-related transcripts, and of 5 others involved in eicosanoid synthesis (including paralogues in both cases) were measured in the head kidney of the salmon using qPCR. All of the assayed immune-related genes and cox2 were pIC-induced, while the other eicosanoid synthesis-related genes were pIC-repressed. Linear regression was used to establish correlations between different immune transcripts, elucidating the cascade of responses to pIC and specialization among paralogues. Regarding the effect of diet on the antiviral immune response, pIC-treated fish fed diets ABP and VEG showed higher transcript levels of tlr3, irf1b, stat1a, isg15b, and gig1 compared to those fed diet MAR. We infer that the observed dietary immunomodulation could be due to the lower proportion of arachidonic acid (ARA), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA) in diets ABP and VEG. Furthermore, our results suggest a major role of dietary ARA in Atlantic salmon immunity, as low ARA proportion in diet VEG coincided with the highest pIC-induction of some immune transcripts (tlr7, stat1c, mxb, and gig1) and the lowest levels of transcripts encoding eicosanoid-synthesizing enzymes (5loxa, 5loxb, and pgds). In contrast, the high ARA/EPA ratio of diet ABP appeared to favor increased expression of transcripts involved in the synthesis of pro

  14. Activity of metabolic enzymes and muscle-specific gene expression in parr and smolts Atlantic salmon Salmo salar L. of different age groups.

    Science.gov (United States)

    Churova, Maria V; Meshcheryakova, Olga V; Veselov, Aleksey E; Efremov, Denis A; Nemova, Nina N

    2017-08-01

    This study was conducted to characterize the energy metabolism level and the features of muscle growth regulation during the development of Atlantic salmon (Salmo salar) inhabiting the Indera River (Kola Peninsula, Russia). The activities of aerobic and anaerobic enzymes (cytochrome c oxidase and lactate dehydrogenase) and carbohydrate metabolism enzymes (glucose-6-phosphate dehydrogenase, glycerol-3-phosphate dehydrogenase, and aldolase) were measured in muscle and liver tissue. Gene expression levels of myosin heavy chain (MyHC), myostatin (MSTN-1a), and myogenic regulatory factors (MRFs-MyoD1a, MyoD1b, MyoD1c, Myf5, myogenin) were measured in the white muscles of salmon parr of ages 0+, 1+, 2+, and 3+ and smolts of ages 2+ and 3+. Multidirectional changes in the activity of enzymes involved in aerobic and anaerobic energy metabolism with age were shown in the white muscles of the parr. The cytochrome c oxidase activity was higher in muscles of underyearlings (0+) and yearlings (1+) and decreased in 2+ and 3+ age groups. The activity of lactate dehydrogenase, in contrast, increased with age. The patterns of changes in expression levels of MyoD1a, MyoD1b, myogenin, MyHC, and MSTN-1a at different ages of the parr were similar. Particularly, the expression of these genes peaked in the yearling parr (1+) and then decreased in elder groups. The differences were revealed in parameters studied between the parr and smolts. The level of aerobic and anaerobic metabolism enzyme activities was higher in the white muscles of smolts than in parr. The activity of carbohydrate metabolism enzymes was decreased in the smolts' livers. The expression levels of MyHC, MyoD1a, MyoD1b, and myogenin were lower in smolts at age 2+ compared to parr. These findings expand our knowledge of age-related and stage-related features of energy metabolism and muscle development regulation in young Atlantic salmon in their natural habitat. The results might be used for monitoring of the salmon

  15. Assessment of Heavy Metals (Cadmium and Lead in Vacuum Packaged Smoked Fish Species (Mackerel, Salmo salar and Oncorhynhus mykiss Marketed in Ankara (Turkey.

    Directory of Open Access Journals (Sweden)

    U. Tansel Şireli

    2015-12-01

    Full Text Available Ankara’daki marketlerde vakum paketli dumanlanmış balık türlerinde (Mackerel, Salmo salar ve Oncorhynhus mykiss ağır metallerin (kadmiyum ve kurşun belirlenmesi. Ankara’daki marketlerde, ticari olarak satılan dumanlanmış ve vakum paketlenmiş balık türlerindeki kadmiyum (Cd ve kurşun (Pb konsantrasyonları değerlendirilmiştir. 2004-2005 yılları arasında Ankara’daki hipermarketlerden toplam 73 adet dumanlanıp paketlenmiş balık fileto örneği temin edilmiştir. İz element konsantrasyonu GFAAS yöntemi ile ölçülmüştür. Cd için sınır değer kuru maddede 0.003-0.034 mg kg -1 olarak bulunurken, Pb için bu değer 0.001-0.791 mg kg-1 olarak bulunmuştur. Analiz edilen tüm balık örneklerinde kadmiyum konsantrasyonu, Türkiye ve Avrupa Birliği Mevzuatı tarafından 0.05 mg kg-1 olarak belirlenen limitlerin altındayken, 27 balık örneğindeki Pb seviyesi Türkiye’deki kabul edilebilir limitleri aşmıştır (0.2 mg kg-1. Buna rağmen, yüksek seviyelerde ölçülen ağır metal konsantrasyonlarında bile, haftada 400 g balık tüketen 60 kg ağırlığında bir yetişkinin tahmini haftalık Pb ve Cd alım miktarı, Joint FAO/WHO Expert Committee tarafından tavsiye edilen geçici tolere edilebilir haftalık alım miktarının (Cd için 7 µg-kg-1 ve Pb için 25 µg kg-1 altında olduğu saptanmıştır

  16. Exploring individual- to population-level impacts of disease on coral reef sponges: using spatial analysis to assess the fate, dynamics, and transmission of Aplysina Red Band Syndrome (ARBS.

    Directory of Open Access Journals (Sweden)

    Cole G Easson

    Full Text Available BACKGROUND: Marine diseases are of increasing concern for coral reef ecosystems, but often their causes, dynamics and impacts are unknown. The current study investigated the epidemiology of Aplysina Red Band Syndrome (ARBS, a disease affecting the Caribbean sponge Aplysina cauliformis, at both the individual and population levels. The fates of marked healthy and ARBS-infected sponges were examined over the course of a year. Population-level impacts and transmission mechanisms of ARBS were investigated by monitoring two populations of A. cauliformis over a three year period using digital photography and diver-collected data, and analyzing these data with GIS techniques of spatial analysis. In this study, three commonly used spatial statistics (Ripley's K, Getis-Ord General G, and Moran's Index were compared to each other and with direct measurements of individual interactions using join-counts, to determine the ideal method for investigating disease dynamics and transmission mechanisms in this system. During the study period, Hurricane Irene directly impacted these populations, providing an opportunity to assess potential storm effects on A. cauliformis and ARBS. RESULTS: Infection with ARBS caused increased loss of healthy sponge tissue over time and a higher likelihood of individual mortality. Hurricane Irene had a dramatic effect on A. cauliformis populations by greatly reducing sponge biomass on the reef, especially among diseased individuals. Spatial analysis showed that direct contact between A. cauliformis individuals was the likely transmission mechanism for ARBS within a population, evidenced by a significantly higher number of contact-joins between diseased sponges compared to random. Of the spatial statistics compared, the Moran's Index best represented true connections between diseased sponges in the survey area. This study showed that spatial analysis can be a powerful tool for investigating disease dynamics and transmission in a

  17. Aplicación de la modelización geoquímica al estudio de pautas evolutivas en las salmueras del Salar de Llamará (Chile. Aproximación de método inverso

    Directory of Open Access Journals (Sweden)

    Gimeno, M. J.

    1996-12-01

    Full Text Available Neutral brines of the Na-Cl type are strongly concentrated by evaporation under and arid climate in the «salar de Llamará» saline system (Chile. The PHRQPITZ geochemical code (which incorporates a chemical model based on Pitzer's equations has been used for calculating ionic activities and saturation indexes, in orden to evaluate the mineral sequence controlling the geochemical evolution of brines. It seems to exist a disequilibrium between brines and atmosphere, since the partial pressure of CO2 calculated by the code shows a progressive increase over the standard mean atmospheric value. All the samples are in equilibrium with both calcite and gypsum. Water activity conditions determine gypsum to be the more stable phase in the Ca-SO4-H2O system. Glauberite reaches saturation at late stage in the brine evolution. The more soluble saline phases do not attain saturation anytime, though more concentrated brines are almost in equilibrium with halite, mirabilite, and thenardite. The results of this thermodynamic treatment are in very good agreement with field observations. Moreover, mass-balance calculations by means of NETPATH code indicate that glauberite precipitation occurs simultaneously with gypsum dissolution.Las salmueras superficiales del salar de Llamará (Chile experimentan un proceso de concentración por evaporación a causa de la aridez del clima al que se ven sometidas. Estas salmueras son del tipo clorurado-sódico y presentan un pH aproximadamente neutro. El tratamiento de los datos hidroquímicos mediante el código de modelización PHRQPITZ (que incorpora un modelo químico basado en las ecuaciones de Pitzer ha permitido realizar el cálculo de actividades iónicas e índices de saturación mineral; estos parámetros se han usado para evaluar la secuencia de precipitación mineral que controla la evolución geoquímica de las salmueras. La presión parcial de CO2 en solución calculada por el código experimenta un ascenso

  18. Microbial diversity in sediment ecosystems (evaporites domes, microbial mats and crusts) of hypersaline Laguna Tebenquiche, Salar de Atacama, Chile

    OpenAIRE

    Ana Beatriz Fernandez; Maria Cecilia Rasuk; Visscher, Pieter T.; Manuel Contreras; Fernando Novoa; Daniel Poire; Patterson, Molly M.; Antonio Ventosa; Maria Eugenia Farias

    2016-01-01

    We combined nucleic acid-based molecular methods, biogeochemical measurements and physicochemical characteristics to investigate microbial sedimentary ecosystems of Laguna Tebenquiche, Atacama Desert, Chile. Molecular diversity and biogeochemistry of hypersaline microbial mats, rhizome-associated concretions and an endoevaporite were compared with: The V4 hypervariable region of the 16S rRNA gene was amplified by pyrosequencing to analyze the total microbial diversity (i.e., bacteria and arch...

  19. Stochastic modelling of direct costs of pancreas disease (PD) in Norwegian farmed Atlantic salmon (Salmo salar L.).

    Science.gov (United States)

    Aunsmo, Arnfinn; Valle, Paul Steinar; Sandberg, Marianne; Midtlyng, Paul Johan; Bruheim, Torkjel

    2010-02-01

    An economic model for estimating the direct costs of disease in industrial aquaculture was developed to include the following areas: biological losses, extraordinary costs, costs of treatment, costs of prevention and insurance pay-out. Direct costs of a pancreas disease (PD) outbreak in Norwegian farmed Atlantic salmon were estimated in the model, using probability distributions for the biological losses and expenditures associated with the disease. The biological effects of PD on mortality, growth, feed conversion and carcass quality and their correlations, together with costs of prevention were established using elicited data from an expert panel, and combined with basal losses in a control model. Extraordinary costs and costs associated with treatment were collected through a questionnaire sent to staff managing disease outbreaks. Norwegian national statistics for 2007 were used for prices and production costs in the model. Direct costs associated with a PD-outbreak in a site stocked with 500,000 smolts (vs. a similar site without the disease) were estimated to NOK (Norwegian kroner) 14.4 million (5% and 95% percentile: 10.5 and 17.8) (NOK=euro0.12 or $0.17 for 2007). Production was reduced to 70% (5% and 95% percentile: 57% and 81%) saleable biomass, and at an increased production cost of NOK 6.0 per kg (5% and 95% percentile: 3.5 and 8.7). Copyright 2009 Elsevier B.V. All rights reserved.

  20. Effect of polyunsatured aldehyde (A3 as an antiparasitary ingredient of Caligus rogercresseyi in the feed of Atlantic salmon, Salmo salar Efecto del aldehído poli-insaturado (A3 como ingrediente antiparasitario de Caligus rogercresseyi en la alimentación de salmón del atlántico, Salmo salar

    Directory of Open Access Journals (Sweden)

    José Troncoso

    2011-11-01

    Full Text Available Some polyunsaturated aldehydes (PUAs such as 2-trans, 4-trans decadenial (A3 have a detrimental effect on the development of copepod sharmful to the salmon industrysuch as Caligus rogercresseyi (sea lice. The purpose of this study was to evaluate the potential use of A3 as a salmon feed ingredient in order to reduce reproduction of Caligus rogercresseyi in infested Atlantic salmon (Salmo salar. The toxicity of A3 was assessed histopathologically for 7 days, using intra-peritoneal injections of different doses (0, 0.24, 0.47, 2.37, 11.86, and 23.71 mg kg-1 in brain, intestine, skin, liver, and muscletissues of Salmosalar at the end of each treatment. The effect of A3 on sea lice was evaluated using 250 Atlantic salmon in an open-flow system of seawater (~13°C. The effect of the dosage in the fish diet was evaluated at two levels (9 mg kg-1, 18 mg kg-1 and considering a control (without A3 for 4, 8, and 12 days, once the sea lice had reached maturity. As a complement, the persistent effect of diluted A3 in sea water (0.5 g L-1 was evaluated at 10, 12, and 14°C for 0, 1, 3, 6, 10, and 15 days; and the maximum persistence was found at 10 days at 10°C. The results showed that the dosages over 0.47 mg kg-1 had no toxic effect on Atlantic salmon, but induced a detrimental effect on Caligus rogercresseyi (reduction of 15% of mature females with a dose of 18 mg kg-1, which could be attributed to alterations in the embryonic development of the sea lice. A3 is a potential supplement in the diet of salmon. However, studies ofits mechanism of action should be undertaken prior to its use.Algunos aldehídos poli-insaturados (PUAs tales como 2-trans, 4-trans decadenal (A3 tienen efecto perjudicial para el desarrollo de copépodos perjudiciales para la industria del salmón, tales como Caligus rogercresseyi (piojo de mar. El objetivo del presente estudio fue evaluar el uso potencial de A3 en alimentación de salmones, de forma de reducir la reproducción de

  1. Microbial Diversity in Sediment Ecosystems (Evaporites Domes, Microbial Mats, and Crusts) of Hypersaline Laguna Tebenquiche, Salar de Atacama, Chile.

    Science.gov (United States)

    Fernandez, Ana B; Rasuk, Maria C; Visscher, Pieter T; Contreras, Manuel; Novoa, Fernando; Poire, Daniel G; Patterson, Molly M; Ventosa, Antonio; Farias, Maria E

    2016-01-01

    We combined nucleic acid-based molecular methods, biogeochemical measurements, and physicochemical characteristics to investigate microbial sedimentary ecosystems of Laguna Tebenquiche, Atacama Desert, Chile. Molecular diversity, and biogeochemistry of hypersaline microbial mats, rhizome-associated concretions, and an endoevaporite were compared with: The V4 hypervariable region of the 16S rRNA gene was amplified by pyrosequencing to analyze the total microbial diversity (i.e., bacteria and archaea) in bulk samples, and in addition, in detail on a millimeter scale in one microbial mat and in one evaporite. Archaea were more abundant than bacteria. Euryarchaeota was one of the most abundant phyla in all samples, and particularly dominant (97% of total diversity) in the most lithified ecosystem, the evaporite. Most of the euryarchaeal OTUs could be assigned to the class Halobacteria or anaerobic and methanogenic archaea. Planctomycetes potentially also play a key role in mats and rhizome-associated concretions, notably the aerobic organoheterotroph members of the class Phycisphaerae. In addition to cyanobacteria, members of Chromatiales and possibly the candidate family Chlorotrichaceae contributed to photosynthetic carbon fixation. Other abundant uncultured taxa such as the candidate division MSBL1, the uncultured MBGB, and the phylum Acetothermia potentially play an important metabolic role in these ecosystems. Lithifying microbial mats contained calcium carbonate precipitates, whereas endoevoporites consisted of gypsum, and halite. Biogeochemical measurements revealed that based on depth profiles of O2 and sulfide, metabolic activities were much higher in the non-lithifying mat (peaking in the least lithified systems) than in lithifying mats with the lowest activity in endoevaporites. This trend in decreasing microbial activity reflects the increase in salinity, which may play an important role in the biodiversity.

  2. Microbial diversity in sediment ecosystems (evaporites domes, microbial mats and crusts of hypersaline Laguna Tebenquiche, Salar de Atacama, Chile

    Directory of Open Access Journals (Sweden)

    Ana Beatriz Fernandez

    2016-08-01

    Full Text Available We combined nucleic acid-based molecular methods, biogeochemical measurements and physicochemical characteristics to investigate microbial sedimentary ecosystems of Laguna Tebenquiche, Atacama Desert, Chile. Molecular diversity and biogeochemistry of hypersaline microbial mats, rhizome-associated concretions and an endoevaporite were compared with: The V4 hypervariable region of the 16S rRNA gene was amplified by pyrosequencing to analyze the total microbial diversity (i.e., bacteria and archaea in bulk samples and, in addition, in detail on a millimeter scale in one microbial mat and in one evaporite. Archaea were more abundant than bacteria. Euryarchaeota was one of the most abundant phyla in all samples, and particularly dominant (97% of total diversity in the most lithified ecosystem, the evaporite. Most of the euryarchaeal OTUs could be assigned to the class Halobacteria or anaerobic and methanogenic archaea. Planctomycetes potentially also play a key role in mats and rhizome-associated concretions, notably the aerobic organoheterotroph members of the class Phycisphaerae. In addition to cyanobacteria, members of Chromatiales and possibly the candidate family Chlorotrichaceae contributed to photosynthetic carbon fixation. Other abundant uncultured taxa such as the candidate division MSBL1, the uncultured MBGB and the phylum Acetothermia potentially play an important metabolic role in these ecosystems. Lithifying microbial mats contained calcium carbonate precipitates, whereas endoevoporites consisted of gypsum and halite. Biogeochemical measurements revealed that based on depth profiles of O2 and sulfide, metabolic activities were much higher in the non-lithifying mat (peaking in the least lithified systems than in lithifying mats with the lowest activity in endoevaporites. This trend in decreasing microbial activity reflects the increase in salinity, which may play an important role in the biodiversity.

  3. Detection of quantitative trait loci (QTL) related to grilsing and late sexual maturation in Atlantic salmon (Salmo salar).

    Science.gov (United States)

    Gutierrez, Alejandro P; Lubieniecki, Krzysztof P; Fukui, Steve; Withler, Ruth E; Swift, Bruce; Davidson, William S

    2014-02-01

    In Atlantic salmon aquaculture, early sexual maturation represents a major problem for producers. This is especially true for grilse, which mature after one sea winter before reaching a desirable harvest weight, rather than after two sea winters. Salmon maturing as grilse have a much lower market value than later maturing individuals. For this reason, most companies desire fish that grow fast and mature late. Marker-assisted selection has the potential to improve the efficiency of selection against early maturation and for late sexual maturation; however, studies identifying age of sexual maturation-related genetic markers are lacking for Atlantic salmon. Therefore, we used a 6.5K single-nucleotide polymorphism (SNP) array to genotype five families from the Mainstream Canada broodstock program and search for SNPs associated with early (grilsing) or late sexual maturation. There were 529 SNP loci that were variable across all five families, and this was the set that was used for quantitative trait loci (QTL) analysis. GridQTL identified two chromosomes, Ssa10 and Ssa21, containing QTL related to grilsing. In contrast, only one QTL, on Ssa18, was found linked to late maturation in Atlantic salmon. Our previous work on these five families did not identify genome-wide significant growth-related QTL on Ssa10, Ssa21, or Ssa18. Therefore, taken together, these results suggest that both grilsing and late sexual maturation are controlled independently of one another and also from growth-related traits. The identification of genomic regions associated with grilsing or late sexual maturation provide an opportunity to incorporate this information into selective breeding programs that will enhance Atlantic salmon farming.

  4. The vgll3 Locus Controls Age at Maturity in Wild and Domesticated Atlantic Salmon (Salmo salar L. Males.

    Directory of Open Access Journals (Sweden)

    Fernando Ayllon

    2015-11-01

    Full Text Available Wild and domesticated Atlantic salmon males display large variation for sea age at sexual maturation, which varies between 1-5 years. Previous studies have uncovered a genetic predisposition for variation of age at maturity with moderate heritability, thus suggesting a polygenic or complex nature of this trait. The aim of this study was to identify associated genetic loci, genes and ultimately specific sequence variants conferring sea age at maturity in salmon. We performed a genome wide association study (GWAS using a pool sequencing approach (20 individuals per river and phenotype of male salmon returning to rivers as sexually mature either after one sea winter (2009 or three sea winters (2011 in six rivers in Norway. The study revealed one major selective sweep, which covered 76 significant SNPs in which 74 were found in a 370 kb region of chromosome 25. Genotyping other smolt year classes of wild and domesticated salmon confirmed this finding. Genotyping domesticated fish narrowed the haplotype region to four SNPs covering 2386 bp, containing the vgll3 gene, including two missense mutations explaining 33-36% phenotypic variation. A single locus was found to have a highly significant role in governing sea age at maturation in this species. The SNPs identified may be both used as markers to guide breeding for late maturity in salmon aquaculture and in monitoring programs of wild salmon. Interestingly, a SNP in proximity of the VGLL3 gene in humans (Homo sapiens, has previously been linked to age at puberty suggesting a conserved mechanism for timing of puberty in vertebrates.

  5. Microbial Diversity in Sediment Ecosystems (Evaporites Domes, Microbial Mats, and Crusts) of Hypersaline Laguna Tebenquiche, Salar de Atacama, Chile

    Science.gov (United States)

    Fernandez, Ana B.; Rasuk, Maria C.; Visscher, Pieter T.; Contreras, Manuel; Novoa, Fernando; Poire, Daniel G.; Patterson, Molly M.; Ventosa, Antonio; Farias, Maria E.

    2016-01-01

    We combined nucleic acid-based molecular methods, biogeochemical measurements, and physicochemical characteristics to investigate microbial sedimentary ecosystems of Laguna Tebenquiche, Atacama Desert, Chile. Molecular diversity, and biogeochemistry of hypersaline microbial mats, rhizome-associated concretions, and an endoevaporite were compared with: The V4 hypervariable region of the 16S rRNA gene was amplified by pyrosequencing to analyze the total microbial diversity (i.e., bacteria and archaea) in bulk samples, and in addition, in detail on a millimeter scale in one microbial mat and in one evaporite. Archaea were more abundant than bacteria. Euryarchaeota was one of the most abundant phyla in all samples, and particularly dominant (97% of total diversity) in the most lithified ecosystem, the evaporite. Most of the euryarchaeal OTUs could be assigned to the class Halobacteria or anaerobic and methanogenic archaea. Planctomycetes potentially also play a key role in mats and rhizome-associated concretions, notably the aerobic organoheterotroph members of the class Phycisphaerae. In addition to cyanobacteria, members of Chromatiales and possibly the candidate family Chlorotrichaceae contributed to photosynthetic carbon fixation. Other abundant uncultured taxa such as the candidate division MSBL1, the uncultured MBGB, and the phylum Acetothermia potentially play an important metabolic role in these ecosystems. Lithifying microbial mats contained calcium carbonate precipitates, whereas endoevoporites consisted of gypsum, and halite. Biogeochemical measurements revealed that based on depth profiles of O2 and sulfide, metabolic activities were much higher in the non-lithifying mat (peaking in the least lithified systems) than in lithifying mats with the lowest activity in endoevaporites. This trend in decreasing microbial activity reflects the increase in salinity, which may play an important role in the biodiversity. PMID:27597845

  6. Genome wide response to dietary tetradecylthioacetic acid supplementation in the heart of Atlantic Salmon (Salmo salar L

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    Grammes Fabian

    2012-05-01

    Full Text Available Abstract Background Under-dimensioned hearts causing functional problems are associated with higher mortality rates in intensive Atlantic salmon aquaculture. Previous studies have indicated that tetradecylthioacetic acid (TTA induces cardiac growth and also stimulates transcription of peroxisome proliferator activated receptors (PPAR αand βin the Atlantic salmon heart. Since cardiac and transcriptional responses to feed are of high interest in aquaculture, the objective of this study was to characterize the transcriptional mechanisms induced by TTA in the heart of Atlantic salmon. Results Atlantic salmon were kept at sea for 17 weeks. During the first 8 weeks the fish received a TTA supplemented diet. Using microarrays, profound transcriptional effects were observed in the heart at the end of the experiment, 9 weeks after the feeding of TTA stopped. Approximately 90% of the significant genes were expressed higher in the TTA group. Hypergeometric testing revealed the over-representation of 35 gene ontology terms in the TTA fed group. The GO terms were generally categorized into cardiac performance, lipid catabolism, glycolysis and TCA cycle. Conclusions Our results indicate that TTA has profound effects on cardiac performance based on results from microarray and qRT-PCR analysis. The gene expression profile favors a scenario of ”physiological”lright hypertrophy recognized by increased oxidative fatty acid metabolism, glycolysis and TCA cycle activity as well as cardiac growth and contractility in the heart ventricle. Increased cardiac efficiency may offer significant benefits in the demanding Aquaculture situations.

  7. Genomewide single nucleotide polymorphism discovery in Atlantic salmon (Salmo salar): validation in wild and farmed American and European populations.

    Science.gov (United States)

    Yáñez, J M; Naswa, S; López, M E; Bassini, L; Correa, K; Gilbey, J; Bernatchez, L; Norris, A; Neira, R; Lhorente, J P; Schnable, P S; Newman, S; Mileham, A; Deeb, N; Di Genova, A; Maass, A

    2016-07-01

    A considerable number of single nucleotide polymorphisms (SNPs) are required to elucidate genotype-phenotype associations and determine the molecular basis of important traits. In this work, we carried out de novo SNP discovery accounting for both genome duplication and genetic variation from American and European salmon populations. A total of 9 736 473 nonredundant SNPs were identified across a set of 20 fish by whole-genome sequencing. After applying six bioinformatic filtering steps, 200 K SNPs were selected to develop an Affymetrix Axiom(®) myDesign Custom Array. This array was used to genotype 480 fish representing wild and farmed salmon from Europe, North America and Chile. A total of 159 099 (79.6%) SNPs were validated as high quality based on clustering properties. A total of 151 509 validated SNPs showed a unique position in the genome. When comparing these SNPs against 238 572 markers currently available in two other Atlantic salmon arrays, only 4.6% of the SNP overlapped with the panel developed in this study. This novel high-density SNP panel will be very useful for the dissection of economically and ecologically relevant traits, enhancing breeding programmes through genomic selection as well as supporting genetic studies in both wild and farmed populations of Atlantic salmon using high-resolution genomewide information. © 2016 John Wiley & Sons Ltd.

  8. Case definition for clinical and subclinical bacterial kidney disease (BKD) in Atlantic Salmon (Salmo salar L.) in New Brunswick, Canada.

    Science.gov (United States)

    Boerlage, A S; Stryhn, H; Sanchez, J; Hammell, K L

    2017-03-01

    Bacterial kidney disease (BKD) is considered an important cause of loss in salmon aquaculture in Atlantic Canada. Causative agent of BKD is the Gram-positive bacteria Renibacterium salmoninarum. Infected salmon are often asymptomatic (subclinical infection), and the disease is considered chronic. One of the challenges in quantifying information from farm production and health records is the application of a standardized case definition. Case definitions for farm-level and cage-level clinical and subclinical BKD were developed using retrospective longitudinal data from aquaculture practices in New Brunswick, Canada, combining (i) industry records of weekly production data including mortalities, (ii) field observations for BKD using reports of veterinarians and/or fish health technicians, (iii) diagnostic submissions and test results and (iv) treatments used to control BKD. Case definitions were evaluated using veterinarians' expert judgements as reference standard. Eighty-nine and 66% of sites and fish groups, respectively, were associated with BKD at least once. For BKD present (subclinical or clinical), sensitivity and specificity of the case definition were 75-100% varying between event, fish group, site cycle and level (site pen). For clinical BKD, sensitivities were 29-64% and specificities 91-100%. Industry data can be used to develop sensitive case definitions. © 2016 John Wiley & Sons Ltd.

  9. Preliminary success using hydrogen peroxide to treat Atlantic salmon, Salmo salar L., affected with experimentally induced amoebic gill disease (AGD).

    Science.gov (United States)

    Adams, M B; Crosbie, P B B; Nowak, B F

    2012-11-01

    Currently, the only effective and commercially used trea