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Sample records for salmo salar linkage

  1. A Dense Brown Trout (Salmo trutta) Linkage Map Reveals Recent Chromosomal Rearrangements in the Salmo Genus and the Impact of Selection on Linked Neutral Diversity

    Science.gov (United States)

    Leitwein, Maeva; Guinand, Bruno; Pouzadoux, Juliette; Desmarais, Erick; Berrebi, Patrick; Gagnaire, Pierre-Alexandre

    2017-01-01

    High-density linkage maps are valuable tools for conservation and eco-evolutionary issues. In salmonids, a complex rediploidization process consecutive to an ancient whole genome duplication event makes linkage maps of prime importance for investigating the evolutionary history of chromosome rearrangements. Here, we developed a high-density consensus linkage map for the brown trout (Salmo trutta), a socioeconomically important species heavily impacted by human activities. A total of 3977 ddRAD markers were mapped and ordered in 40 linkage groups using sex- and lineage-averaged recombination distances obtained from two family crosses. Performing map comparison between S. trutta and its sister species, S. salar, revealed extensive chromosomal rearrangements. Strikingly, all of the fusion and fission events that occurred after the S. salar/S. trutta speciation happened in the Atlantic salmon branch, whereas the brown trout remained closer to the ancestral chromosome structure. Using the strongly conserved synteny within chromosome arms, we aligned the brown trout linkage map to the Atlantic salmon genome sequence to estimate the local recombination rate in S. trutta at 3721 loci. A significant positive correlation between recombination rate and within-population nucleotide diversity (π) was found, indicating that selection constrains variation at linked neutral sites in brown trout. This new high-density linkage map provides a useful genomic resource for future aquaculture, conservation, and eco-evolutionary studies in brown trout. PMID:28235829

  2. A Dense Brown Trout (Salmo trutta Linkage Map Reveals Recent Chromosomal Rearrangements in the Salmo Genus and the Impact of Selection on Linked Neutral Diversity

    Directory of Open Access Journals (Sweden)

    Maeva Leitwein

    2017-04-01

    Full Text Available High-density linkage maps are valuable tools for conservation and eco-evolutionary issues. In salmonids, a complex rediploidization process consecutive to an ancient whole genome duplication event makes linkage maps of prime importance for investigating the evolutionary history of chromosome rearrangements. Here, we developed a high-density consensus linkage map for the brown trout (Salmo trutta, a socioeconomically important species heavily impacted by human activities. A total of 3977 ddRAD markers were mapped and ordered in 40 linkage groups using sex- and lineage-averaged recombination distances obtained from two family crosses. Performing map comparison between S. trutta and its sister species, S. salar, revealed extensive chromosomal rearrangements. Strikingly, all of the fusion and fission events that occurred after the S. salar/S. trutta speciation happened in the Atlantic salmon branch, whereas the brown trout remained closer to the ancestral chromosome structure. Using the strongly conserved synteny within chromosome arms, we aligned the brown trout linkage map to the Atlantic salmon genome sequence to estimate the local recombination rate in S. trutta at 3721 loci. A significant positive correlation between recombination rate and within-population nucleotide diversity (π was found, indicating that selection constrains variation at linked neutral sites in brown trout. This new high-density linkage map provides a useful genomic resource for future aquaculture, conservation, and eco-evolutionary studies in brown trout.

  3. Effects of hydropeaking on the spawning behaviour of Atlantic salmon Salmo salar and brown trout Salmo trutta.

    Science.gov (United States)

    Vollset, K W; Skoglund, H; Wiers, T; Barlaup, B T

    2016-06-01

    An in situ camera set-up was used to study the spawning activity of Atlantic salmon Salmo salar and brown trout Salmo trutta throughout two consecutive seasons in a spawning area affected by hydropower-related pulse flows due to hydropeaking. The purpose was to test whether the flow variation discouraged spawning in shallow areas or motivated spawning into areas with elevated risk of incubation mortality. There were more S. salar observed on the spawning ground during days with high discharge. The presence of S. salar in the spawning grounds was not affected by the hydropeaking cycles of the preceding night. Female S. salar were observed preparing nests within the first hour after water discharge had increased to levels suitable for spawning. In contrast, the number of S. trutta was not correlated with flow and nest preparation was also observed at a discharge corresponding to the lowest discharge levels during a hydropeaking cycle. Survival was generally high in nests excavated the following winter, with only 5·4% suffering mortality due to dewatering. The results suggest that S. salar may respond rapidly to variable-flow conditions and utilize short windows with suitable flows for spawning. Smaller S. trutta may utilize low-flow conditions to spawn in areas that are not habitable by larger S. salar during low flow. © 2016 The Fisheries Society of the British Isles.

  4. 50 CFR 226.217 - Critical habitat for the Gulf of Maine Distinct Population Segment of Atlantic Salmon (Salmo salar).

    Science.gov (United States)

    2010-10-01

    ... Distinct Population Segment of Atlantic Salmon (Salmo salar). 226.217 Section 226.217 Wildlife and... Distinct Population Segment of Atlantic Salmon (Salmo salar). Critical habitat is designated to include all... the Gulf of Maine Distinct Population Segment of Atlantic Salmon (GOM DPS), except for those...

  5. Predictability of multispecies competitive interactions in three populations of Atlantic salmon Salmo salar.

    Science.gov (United States)

    Houde, A L S; Wilson, C C; Neff, B D

    2015-04-01

    Juvenile Atlantic salmon Salmo salar from three allopatric populations (LaHave, Sebago and Saint-Jean) were placed into artificial streams with combinations of four non-native salmonids: brown trout Salmo trutta, rainbow trout Oncorhynchus mykiss, Chinook salmon Oncorhynchus tshawytscha and coho salmon Oncorhynchus kisutch. Non-additive effects, as evidenced by lower performance than predicted from weighted summed two-species competition trials, were detected for S. salar fork length (LF ) and mass, but not for survival, condition factor or riffle use. These data support emerging theory on niche overlap and species richness as factors that can lead to non-additive competition effects. © 2015 The Fisheries Society of the British Isles.

  6. 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...

  7. A microsatellite baseline for genetic stock identification of European Atlantic salmon (Salmo salar L.)

    DEFF Research Database (Denmark)

    Gilbey, John; Coughlan, Jamie; Wennevik, Vidar

    2018-01-01

    Atlantic salmon (Salmo salar L.) populations from different river origins mix in the North Atlantic during the marine life stage. To facilitate marine stock identification, we developed a genetic baseline covering the European component of the species' range excluding the Baltic Sea, from the Rus...

  8. 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...

  9. 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.

  10. Evidence of Atlantic salmon Salmo salar fry movement between fresh water and a brackish environment.

    Science.gov (United States)

    Taal, I; Rohtla, M; Saks, L; Svirgsden, R; Kesler, M; Matetski, L; Vetemaa, M

    2017-08-01

    This study reports descent of Atlantic salmon Salmo salar fry from their natal streams to brackish waters of the Baltic Sea and their use of this environment as an alternative rearing habitat before ascending back to freshwater streams. To the authors' knowledge, residency in a brackish environment has not previously been demonstrated in S. salar fry. Recruitment success and evolutionary significance of this alternative life-history strategy are presently not known. © 2017 The Fisheries Society of the British Isles.

  11. 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...

  12. 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...

  13. Seasonal shift in the effects of predators on juvenile Atlantic salmon (Salmo salar) energetics

    Science.gov (United States)

    Darren M. Ward; Keith H. Nislow; Carol L. Folt; James Grant

    2011-01-01

    Predator effects on prey populations are determined by the number of prey consumed and effects on the traits of surviving prey. Yet the effects of predators on prey traits are rarely evaluated in field studies. We measured the effects of predators on energetic traits (consumption and growth rates) of juvenile Atlantic salmon (Salmo salar) in a...

  14. 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...

  15. Evidence for episodic acidification effects on migrating Atlantic salmon Salmo salar smolts

    Science.gov (United States)

    Kelly, John T; Lerner, Darrren T.; O'Dea, Michael F.; Regish, Amy M.; Monette, Michelle Y.; Hawkes, J.P.; Nislow, Keith H.; McCormick, Stephen

    2015-01-01

    Field studies were conducted to determine levels of gill aluminium as an index of acidification effects on migrating Atlantic salmon Salmo salar smolts in the north-eastern U.S.A. along mainstem river migration corridors in several major river basins. Smolts emigrating from the Connecticut River, where most (but not all) tributaries were well buffered, had low or undetectable levels of gill aluminium and high gill Na+/K+-ATPase (NKA) activity. In contrast, smolts emigrating from the upper Merrimack River basin where most tributaries are characterized by low pH and high inorganic aluminium had consistently elevated gill aluminium and lower gill NKA activity, which may explain the low adult return rates of S. salar stocked into the upper Merrimack catchment. In the Sheepscot, Narraguagus and Penobscot Rivers in Maine, river and year-specific effects on gill aluminium were detected that appeared to be driven by underlying geology and high spring discharge. The results indicate that episodic acidification is affecting S. salar smolts in poorly buffered streams in New England and may help explain variation in S. salar survival and abundance among rivers and among years, with implications for the conservation and recovery of S. salar in the north-eastern U.S.A. These results suggest that the physiological condition of outmigrating smolts may serve as a large-scale sentinel of landscape-level recovery of atmospheric pollution in this and other parts of the North Atlantic region.

  16. A free-living amoeba with unusual pattern of mitochondrial structure isolated from Atlantic salmon, Salmo salar L

    Czech Academy of Sciences Publication Activity Database

    Dyková, Iva; Veverková, Marie; Fiala, Ivan; Macháčková, Blanka

    2002-01-01

    Roč. 41, - (2002), s. 415-419 ISSN 0065-1583 R&D Projects: GA AV ČR IAA6022202 Institutional research plan: CEZ:AV0Z6022909 Keywords : free-living amoeba * mitochondrial cristae * Salmo salar Subject RIV: EA - Cell Biology Impact factor: 0.446, year: 2002

  17. 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...

  18. 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.

  19. Quantification of vitellogenin in Atlantic salmon (Salmo salar) plasma by radioimmunoassay

    International Nuclear Information System (INIS)

    Idler, D.R.; Hwang, S.J.; Crim, L.W.

    1979-01-01

    An antibody prepared against salmon egg yolk proteins has been used to quantify Atlantic salmon (Salmo salar) plasma vitellogenin using radioimmunoassay. A low molecular weight fraction isolated from salmon egg yolk was used for radioiodination and as standard solution because plasma vitellogenin could not be iodinated successfully. Parallelism of the egg yolk standard to displacement given by a fraction isolated from vitellogenic salmon plasma and dilutions of plasma samples allowed the assay to be used to evaluate the state of gonadal development of migrating females several months in advance of spawning and for sexing relatively immature salmon. (author)

  20. 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; Pedersen, Mona E.

    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...

  1. 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...

  2. Phosphorus flux due to Atlantic salmon (Salmo salar) in an oligotrophic upland stream: effects of management and demography

    Science.gov (United States)

    Keith H. Nislow; John D. Armstrong; Simon. McKelvey

    2004-01-01

    Little is known concerning the role of Atlantic salmon (Salmo salar) in the transport of nutrients to and from river systems. We used demographic data from the River Bran, an oligotrophic river in Scotland, UK, to construct a budget for the transport of phosphorus (P) and applied it to investigate the effects of management strategies and demographic...

  3. 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.

  4. Growth evaluation of atlantic salmon (Salmo salar) raised in seawater or freshwater and fed either fishmeal based on marine-free diets

    Science.gov (United States)

    A forty week feeding study was conducted with Atlantic salmon (Salmo salar) smolts in two recirculating aquaculture systems. Twelve salmon (average initial weight 117 g; initial density 9.4 kg/m3) were stocked per tank. Two identical systems were used and contained either freshwater (0 ppt) or sea...

  5. Growth evaluation of Atlantic Salmon (Salmo salar) raised in seawater or freshwater and fed either fishmeal based or marine-free diets

    Science.gov (United States)

    A forty week feeding study was conducted with Atlantic salmon (Salmo salar) smolts in two recirculating aquaculture systems. Two identical systems were used and contained either freshwater (0 ppt) or seawater (about 30 ppt). Fish were fed one of two diets, a control diet containing fishmeal and fi...

  6. Trans-generational maternal effect: temperature influences egg size of the offspring in Atlantic salmon Salmo salar.

    Science.gov (United States)

    Jonsson, B; Jonsson, N

    2016-08-01

    Effect of increased temperature during egg maturation on the mass of single eggs produced by the offspring was investigated experimentally in Atlantic salmon Salmo salar. Mass of eggs produced by next-generation females was larger when their mothers experienced warmer water during the last two months of egg maturation, relative to those that experienced unheated river water. There was no similar trans-generational paternal effect on offspring egg mass. © 2016 The Fisheries Society of the British Isles.

  7. Evidence for an autumn downstream migration of Atlantic salmon Salmo salar (Linnaeus) and brown trout Salmo trutta (Linnaeus) parr to the Baltic Sea

    Science.gov (United States)

    Taal, Imre; Kesler, Martin; Saks, Lauri; Rohtla, Mehis; Verliin, Aare; Svirgsden, Roland; Jürgens, Kristiina; Vetemaa, Markus; Saat, Toomas

    2014-06-01

    In the eastern Baltic rivers, anadromous salmonid parr are known to smoltify and migrate to the sea from March until June, depending on latitude, climate and hydrological conditions. In this study, we present the first records of autumn descent of brown trout Salmo trutta and Atlantic salmon Salmo salar from the Baltic Sea Basin. Otolith microchemistry analyses revealed that these individuals hatched in freshwater and had migrated to the brackish water shortly prior to capture. The fish were collected in 2006, 2008, 2009 and 2013 from Eru Bay (surface salinity 4.5-6.5 ‰), Gulf of Finland. This relatively wide temporal range of observations indicates that the autumn descent of anadromous salmonids is not a random event. These results imply that autumn descent needs more consideration in the context of the effective stock management, assessment and restoration of Baltic salmonid populations and their habitats.

  8. Identification and molecular docking study of novel angiotensin-converting enzyme inhibitory peptides from Salmo salar using in silico methods.

    Science.gov (United States)

    Yu, Zhipeng; Chen, Yang; Zhao, Wenzhu; Li, Jianrong; Liu, Jingbo; Chen, Feng

    2018-01-25

    In order to circumvent some challenges of the classical approach, the in silico method has been applied to the discovery of angiotensin-converting enzyme (ACE) inhibitory peptides from food proteins. In this study, some convenient and efficient in silico tools were utilized to identify novel ACE inhibitory peptides from Salmo salar. Collagen from Salmo salar was digested in silico into hundreds of peptides. Results revealed that tetrapeptides PGAR and IGPR showed potent ACE inhibitory activity, with IC 50 values of 0.598 ± 0.12 and 0.43 ± 0.09 mmol L -1 , respectively. The molecular docking result showed that PGAR and IGPR interact with ACE mostly via hydrogen bonds and attractive charge. Peptide IGPR interacts with Zn + at the ACE active site, showing high inhibitory activity. Interaction with Zn + in ACE may lead to higher inhibitory activity of peptides, and Pi interactions may promote the effect of peptides on ACE. The in silico method can be an effective method to predict potent ACE inhibitory peptides from food proteins. © 2018 Society of Chemical Industry. © 2018 Society of Chemical Industry.

  9. 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, salmon, and may impair the ability to cope with new environments.

  10. Temperature selection of juvenile Atlantic salmon (Salmo salar) as influenced by various toxic substances

    Energy Technology Data Exchange (ETDEWEB)

    Peterson, R H

    1976-08-01

    Previous exposure to sodium pentachlorophenate (NaPCP), Guthion, malathion, Dursban, and Dibrom lowered the preferred temperature for juvenile Atlantic salmon (Salmo salar) tested in a horizontal temperature gradient. Lindane, CuSO/sub 4/, ZnSO/sub 4/, CdSO/sub 4/, Sevin, heptachlor, and fenitrothion did not change the preferred temperature significantly. Comparison with other published results indicates that those substances that increase the preferred temperature are more toxic (based on relevant changes in 24-h LC50) at low temperatures and vice versa. It is suggested that such shifts in selected temperature may be of potential immediate, short-term, survival value to the fish. (auth)

  11. 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)....

  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. 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 release...... 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......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...... as fry, half-year olds and oneyear olds. Our results indicate that fish released at the fry and half-year stage produce smaller smolts, and migrate later in the year than their counterparts released at one-year of age, for both the Ätran and the Burrishoole populations. While fry had the lowest...

  14. Divergent trends in life-history traits between Atlantic salmon Salmo salar of wild and hatchery origin in the Baltic Sea.

    Science.gov (United States)

    Vainikka, A; Kallio-Nyberg, I; Heino, M; Koljonen, M-L

    2010-02-01

    Four Atlantic salmon Salmo salar stocks in the Baltic Sea, varying in their breeding history, were studied for changes in life-history traits over the years 1972-1995. Total length (L(T)) at age of captured (L(TC)) fish had increased throughout the study period, partly due to increased temperature and increased L(T) at release, (L(TR)) but also due to remaining cohort effects that could represent unaccounted environmental or genetic change. Simultaneously, maturation probabilities controlled for water temperature, L(TC) and L(TR) had increased in all stocks. The least change was observed in the River Tornionjoki S. salar that was subject only to supportive stockings originating from wild parents. These results suggest a long-term divergence between semi-natural and broodstock-based S. salar stocks. Increased L(T) at age explained advanced maturation only marginally, and it remains an open question to what extent the generally increased probabilities to mature at early age reflected underlying genetic changes.

  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. 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.

  17. Consistent melanophore spot patterns allow long-term individual recognition of Atlantic salmon Salmo salar.

    Science.gov (United States)

    Stien, L H; Nilsson, J; Bui, S; Fosseidengen, J E; Kristiansen, T S; Øverli, Ø; Folkedal, O

    2017-12-01

    The present study shows that permanent melanophore spot patterns in Atlantic salmon Salmo salar make it possible to use images of the operculum to keep track of individual fish over extended periods of their life history. Post-smolt S. salar (n = 246) were initially photographed at an average mass of 98 g and again 10 months later after rearing in a sea cage, at an average mass of 3088 g. Spots that were present initially remained and were the most overt (largest) 10 months later, while new and less overt spots had developed. Visual recognition of spot size and position showed that fish with at least four initial spots were relatively easy to identify, while identifying fish with less than four spots could be challenging. An automatic image analysis method was developed and shows potential for fast match processing of large numbers of fish. The current findings promote visual recognition of opercular spots as a welfare-friendly alternative to tagging in experiments involving salmonid fishes. © The Authors. Journal of Fish Biology published by John Wiley & Sons Ltd on behalf of The Fisheries Society of the British Isles.

  18. 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.

  19. The effects of long-term 20 mg/L carbon dioxide exposure on the health and performance of Atlantic salmon Salmo salar post-smolts in water recirculation aquaculture systems

    Science.gov (United States)

    Previous research and experience has linked elevated dissolved carbon dioxide (CO2) to reduced growth performance, poor feed conversion, and a variety of health issues in farm-raised fish, including Atlantic salmon Salmo salar. Supplemental control measures in water recirculation aquaculture systems...

  20. 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....... In contrast, no increase of titres was seen in the bath vaccinated and untreated groups. Marked cellular reactions in the abdominal cavity of injected fish were registered. A total of 3000 fish have been tagged and released to evaluate the effect of vaccination on the recapture rate. The implications...

  1. Effects of rearing density and dietary fat content on burst-swim performance and oxygen transport capacity in juvenile Atlantic salmon Salmo salar.

    Science.gov (United States)

    Hammenstig, D; Sandblom, E; Axelsson, M; Johnsson, J I

    2014-10-01

    The effects of hatchery rearing density (conventional or one third of conventional density) and feeding regime (high or reduced dietary fat levels) on burst-swim performance and oxygen transport capacity were studied in hatchery-reared Atlantic salmon Salmo salar, using wild fish as a reference group. There was no effect of rearing density or food regime on swimming performance in parr and smolts. The maximum swimming speed of wild parr was significantly higher than that of hatchery-reared conspecifics, while no such difference remained at the smolt stage. In smolts, relative ventricle mass was higher in wild S. salar compared with hatchery-reared fish. Moreover, wild S. salar had lower maximum oxygen consumption following a burst-swim challenge than hatchery fish. There were no effects of hatchery treatment on maximum oxygen consumption or relative ventricle mass. Haemoglobin and haematocrit levels, however, were lower in low-density fish than in fish reared at conventional density. Furthermore, dorsal-fin damage, an indicator of aggression, was similar in low-density reared and wild fish and lower than in S. salar reared at conventional density. Together, these results suggest that reduced rearing density is more important than reduced dietary fat levels in producing an S. salar smolt suitable for supplementary release. © 2014 The Fisheries Society of the British Isles.

  2. Evidence for long-term change in length, mass and migration phenology of anadromous spawners in French Atlantic salmon Salmo salar.

    Science.gov (United States)

    Bal, G; Montorio, L; Rivot, E; Prévost, E; Baglinière, J-L; Nevoux, M

    2017-06-01

    This study provides new data on Atlantic salmon Salmo salar life-history traits across France. Using a long-term recreational angling database (1987-2013) covering 34 rivers in three regions (genetic units), a decline in individual length, mass and a delayed adult return to French rivers was reported. Temporal similarities in trait variations between regions may be attributed to common change in environmental conditions at sea. The relative rate of change in phenotypic traits was more pronounced in early maturing fish [1 sea-winter (1SW) fish] than in late maturing fish (2SW fish). Such contrasted response within populations highlights the need to account for the diversity in life histories when exploring mechanisms of phenotypic change in S. salar. Such detailed life-history data on returning S. salar have not previously been reported from France. This study on French populations also contributes to reducing the gap in knowledge by providing further empirical evidence of a global pattern in S. salar across its distribution range. Results are consistent with the hypothesis that the observed changes in life-history traits are primarily associated with environmental changes in the North Atlantic Ocean. They also emphasize the presence of less important, but still significant contrasts between region and life history. © 2017 The Fisheries Society of the British Isles.

  3. 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...

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

    Directory of Open Access Journals (Sweden)

    Kelli Anderson

    2017-11-01

    Full Text Available 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.

  5. 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

    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......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...... smolts from each density treatment were individually tagged with passive integrated transponder (PIT) tags and released 3.2 km upstream of a stationary antenna array in a natural stream. There were no significant differences in length, body mass, or condition between fish from the two density treatments...

  6. Development of Atlantic salmon (Salmo salar) eggs and alevins under varied temperature regimes

    Energy Technology Data Exchange (ETDEWEB)

    Peterson, R H; Spinney, H C.E.; Sreedharan, A

    1977-01-01

    Atlantic salmon (Salmo salar) eggs and alevins were raised under conditions where the temperature was systematically varied either at fertilization, at the eyed egg stage, or at hatching. Mortality was more than 20% in eggs started immediately after fertilization at constant incubation temperatures <4/sup 0/C as compared with 5% or less at temperatures >4/sup 0/C. Alevins that eyed at 8/sup 0/C and higher were progressively smaller the higher the temperature. The optimum temperature from fertilization to eye pigmentation was near 6/sup 0/C. Eyed eggs reared at lower temperatures until hatching were larger than those hatched at higher temperatures. This size differential was maintained until the yolk was completely absorbed at all posthatching temperatures investigated. Sudden decreases in temperature at the eyed egg and hatching stages induced severe edema of the alevin yolk sac, resulting in slower growth and increased mortality.

  7. Tissue astaxanthin and canthaxanthin distribution in rainbow trout (Oncorhynchus mykiss) and Atlantic salmon (Salmo salar).

    Science.gov (United States)

    Page, G I; Davies, S J

    2006-01-01

    A comparative investigation of tissue carotenoid distribution between rainbow trout, Oncorhynchus mykiss, and Atlantic salmon, Salmo salar, was undertaken to identify the relative efficiency of utilization of astaxanthin and canthaxanthin. Higher apparent digestibility coefficients (ADCs) (96% in trout vs. 28-31% in salmon; Ptrout vs. 5.5% in salmon; Ptrout. Astaxanthin deposition was higher than canthaxanthin in rainbow trout, while the reverse was true for Atlantic salmon, suggesting species-specificity in carotenoid utilization. The white muscle (95% in trout vs. 93% in salmon) and kidneys (0.5% in trout vs. 0.2% in salmon) represented higher proportions of the total body carotenoid pool in rainbow trout than in Atlantic salmon (Ptrout; Ptrout. Liver catabolism is suspected to be a critical determinant in carotenoid clearance, with higher catabolism expected in Atlantic salmon than in rainbow trout.

  8. Protein degradation systems in the skeletal muscles of parr and smolt Atlantic salmon Salmo salar L. and brown trout Salmo trutta L.

    Science.gov (United States)

    Kantserova, Nadezda P; Lysenko, Liudmila A; Veselov, Alexey E; Nemova, Nina N

    2017-08-01

    Although protein degradation limits the rate of muscle growth in fish, the role of proteolytic systems responsible for degrading myofibrillar proteins in skeletal muscle is not well defined. The study herein aims to evaluate the role of calpains (calcium-activated proteases) and proteasomes (ATP-dependent proteases) in mediating muscle protein turnover at different life stages in wild salmonids. Protease activities were estimated in Atlantic salmon (Salmo salar L.) and brown trout (Salmo trutta L.) parr and smolts from the Indera River (Kola Peninsula, Russia). Calpain and proteasome activities in Atlantic salmon skeletal muscles were lower in smolts as compared with parr. Reduced muscle protein degradation accompanying Atlantic salmon parr-smolt transformation appeared to provide intense muscle growth essential for a minimum threshold size achievement that is required for smoltification. Calpain and proteasome activities in brown trout parr and smolts at age 3+ did not significantly differ. However, calpain activity was higher in smolts brown trout 4+ as compared with parr, while proteasome activity was lower. Results suggest that brown trout smoltification does not correspond with intense muscle growth and is more facultative and plastic in comparison with Atlantic salmon smoltification. Obtained data on muscle protein degradation capacity as well as length-weight parameters of fish reflect differences between salmon and trout in growth and smoltification strategies.

  9. Application of Quality Index Method (QIM) scheme in shelf-life study of farmed Atlantic salmon ( Salmo salar )

    DEFF Research Database (Denmark)

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

    2002-01-01

    measurements (compression test). Maximum storage time in ice was determined with QDA and fat content by Soxhlet extraction. A high correlation between QIM and storage time in ice was found. Storage time could be predicted with +/- 2 d. TVC increased exponentially with storage and was dominated by H2S......Salmon (Salmo salar) was stored in ice up to 24 d, and changes during storage were observed with sensory evaluation using the Quality Index Method (QIM), and Quantitative Descriptive Analysis (QDA), total viable counts (TVC), hydrogen sulfide (H2S)-producing bacteria, and instrumental texture......-producing bacteria after 20 d in ice, which was the maximum storage time. Texture measurements indicated softening of salmon flesh with storage...

  10. From the viral perspective: infectious salmon anemia virus (ISAV) transcriptome during the infective process in Atlantic salmon (Salmo salar).

    Science.gov (United States)

    Valenzuela-Miranda, Diego; Cabrejos, María Eugenia; Yañez, José Manuel; Gallardo-Escárate, Cristian

    2015-04-01

    The infectious salmon anemia virus (ISAV) is a severe disease that mainly affects the Atlantic salmon (Salmo salar) aquaculture industry. Although several transcriptional studies have aimed to understand Salmon-ISAV interaction through the evaluation of host-gene transcription, none of them has focused their attention upon the viral transcriptional dynamics. For this purpose, RNA-Seq and RT-qPCR analyses were conducted in gills, liver and head-kidney of S. salar challenged by cohabitation with ISAV. Results evidence the time and tissue transcript patterns involved in the viral expression and how the transcription levels of ISAV segments are directly linked with the protein abundance found in other virus of the Orthomyxoviridae family. In addition, RT-qPCR result evidenced that quantification of ISAV through amplification of segment 3 would result in a more sensitive approach for detection and quantification of ISAV. This study offers a more comprehensive approach regarding the ISAV infective process and gives novel knowledge for its molecular detection. Copyright © 2014 Elsevier B.V. All rights reserved.

  11. 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.

  12. Transcriptome sequencing of Atlantic salmon (Salmo salar L.) notochord prior to development of the vertebrae provides clues to regulation of positional fate, chordoblast lineage and mineralisation

    OpenAIRE

    Wang, Shou; Furmanek, Tomasz; Kryvi, Harald; Krossøy, Christel; Totland, Geir Kåre; Grotmol, Sindre; Wargelius, Anna

    2014-01-01

    Background In teleosts such as Atlantic salmon (Salmo salar L.), segmentation and subsequent mineralisation of the notochord during embryonic stages are essential for normal vertebrae formation. However, the molecular mechanisms leading to segmentation and mineralisation of the notochord are poorly understood. The aim of this study was to identify genes/pathways acting in gradients over time and along the anterior-posterior axis during notochord segmentation and immediately prior to mineralis...

  13. Accelerated recovery of Atlantic salmon (Salmo salar) from effects of crowding by swimming.

    Science.gov (United States)

    Veiseth, Eva; Fjaera, Svein Olav; Bjerkeng, Bjørn; Skjervold, Per Olav

    2006-07-01

    The effects of post-crowding swimming velocity (0, 0.35, and 0.70 m/s) and recovery time (1.5, 6, and 12 h) on physiological recovery and processing quality parameters of adult Atlantic salmon (Salmo salar) were determined. Atlantic salmon crowded to a density similar to that of a commercial slaughter process (>200 kg/m(3), 40 min) were transferred to a swimming chamber for recovery treatment. Osmolality and concentrations of cortisol, glucose and lactate in blood plasma were used as physiological stress indicators, whereas image analyses of extent and duration of rigor contraction, and fillet gaping were used as measures of processing quality. Crowded salmon had a 5.8-fold higher plasma cortisol concentration than control salmon (Prigor mortis contraction. However, subjecting crowded salmon to active swimming for 6 h before slaughter delayed the onset of rigor mortis contraction from 2.5 to 7.5 h post mortem. The extent of rigor mortis contraction was also affected by crowding and post-stress swimming activity (Prigor mortis contraction, which has a positive technological implication for the salmon processing industry.

  14. Arteriosclerosis in the ventral aorta and epicarditis in the bulbus arteriosus of Atlantic salmon (Salmo salar L).

    Science.gov (United States)

    Dalum, A S; Kristthorsdottir, K H; Griffiths, D J; Bjørklund, K; Poppe, T T

    2017-06-01

    Spontaneous mortality of seemingly healthy, farmed Atlantic salmon (Salmo salar L) is an increasing problem in Norwegian aquaculture. In this study, we present a morphological study of the previously undescribed syndrome of arteriosclerosis of the ventral aorta and epicarditis of the adjacent bulbus arteriosus found in farmed Atlantic salmon, with wild-captured fish as a control group. Both the ventral aorta and epicardium are vital for correct arterial compliance and vascular resistance in the respiratory capillaries of the gills. We discuss the possible implications of ventral aorta arteriosclerosis and epicarditis for blood vascular health and in particular for the increasing frequency of spontaneous gill bleeding in farmed salmon. As both these conditions primarily occur in farmed salmon, we suggest that they should be considered pathological. © 2016 John Wiley & Sons Ltd.

  15. 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...

  16. Genetic variation in threshold reaction norms for alternative reproductive tactics in male Atlantic salmon, Salmo salar.

    Science.gov (United States)

    Piché, Jacinthe; Hutchings, Jeffrey A; Blanchard, Wade

    2008-07-07

    Alternative reproductive tactics may be a product of adaptive phenotypic plasticity, such that discontinuous variation in life history depends on both the genotype and the environment. Phenotypes that fall below a genetically determined threshold adopt one tactic, while those exceeding the threshold adopt the alternative tactic. We report evidence of genetic variability in maturation thresholds for male Atlantic salmon (Salmo salar) that mature either as large (more than 1 kg) anadromous males or as small (10-150 g) parr. Using a common-garden experimental protocol, we find that the growth rate at which the sneaker parr phenotype is expressed differs among pure- and mixed-population crosses. Maturation thresholds of hybrids were intermediate to those of pure crosses, consistent with the hypothesis that the life-history switch points are heritable. Our work provides evidence, for a vertebrate, that thresholds for alternative reproductive tactics differ genetically among populations and can be modelled as discontinuous reaction norms for age and size at maturity.

  17. 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

    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...... were also evaluated. Atlantic salmon of three different size classes (I: 80 to 99 mm fork length (FL), II: 100 to 119 mm FL, III: 120 to 135 mm FL) were allocated to each of five experimental treatment groups: control, sham-operated (surgery without PIT-tag implantation), 23 mm PIT-tag implantation...... 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...

  18. Identification of Atlantic salmon (Salmo salar) and rainbow trout (Oncorhynchus mykiss) by using polymerase chain reaction amplification and restriction analysis of the mitochondrial cytochrome b gene.

    Science.gov (United States)

    Carrera, E; García, T; Céspedes, A; González, I; Sanz, B; Hernández, P E; Martín, R

    1998-04-01

    Restriction site analysis of polymerase chain reaction (PCR) products from a conserved region of the cytochrome b gene has been used for the identification of fresh and smoked samples of Atlantic salmon (Salmo salar) and rainbow trout (Oncorhynchus mykiss). Digestion of the 359-bp PCR product with the endonucleases EcoRV and TaqI yielded specific banding patterns for salmon and trout. This genetic marker can be very useful for detecting fraudulent substitution of the cheaper smoked trout for the more expensive smoked salmon.

  19. Supplementing a commercial diet for atlantic salmon (Salmo salar L.) with arginine, glutamate or tetradecylthioacetic acid (TTA). impact on production efficiency, slaughter parameters and flesh quality

    OpenAIRE

    Rahnama, Behzad

    2010-01-01

    The present study was carried out to evaluate the effects of supplementing a commercial diets with 1.5% L-arginine, 1.5% L-glutamate or 0.25% tetradecylthioacetic acid (TTA) on feed intake, feed utilization and growth parameters of Atlantic salmon (Salmo salar L.) during the critical periods after sea transfer with regard to seawater adaptation and onwards, from April to September. In the case of TTA, fish were fed until they reached a weight gain of 0.2% of the initial body weight, thereafte...

  20. 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.

  1. Early enrichment effects on brain development in hatchery-reared Atlantic salmon (Salmo salar): no evidence for a critical period

    DEFF Research Database (Denmark)

    Näslund, Joacim; Aarestrup, Kim; Thomassen, Søren T.

    2012-01-01

    was released into nature and recaptured at smoltification. These stream-reared smolts developed smaller brains than the hatchery reared smolts, irrespective of initial enrichment treatment. These novel findings do not support the hypothesis that there is a critical early period determining the brain growth...... trajectory. In contrast, our results indicate that brain growth is plastic in relation to environment. In addition, we show allometric growth in brain substructures over juvenile development, which suggests that comparisons between groups of different body size should be made with caution. These results can......In hatcheries, fish are normally reared in barren environments, which have been reported to affect their phenotypic development compared with wild conspecifics. In this study, Atlantic salmon (Salmo salar) alevins were reared in conventional barren hatchery trays or in either of two types...

  2. Ichthyobodo salmonis sp. n. (Ichthyobodonidae, Kinetoplastida), an euryhaline ectoparasite infecting Atlantic salmon (Salmo salar L.)

    Science.gov (United States)

    ISAKSEN, TROND E.; KARLSBAKK, EGIL; WATANABE, KUNINORI; NYLUND, ARE

    2011-01-01

    SUMMARY Phylogenetic analyses of SSU rDNA sequences have previously revealed the existence of 2 Ichthyobodo species able to infect Atlantic salmon (Salmo salar L.). Ichthyobodo necator sensu stricto (s.s.) is assumed to be a freshwater parasite, while a genetically distinct but undescribed species, Ichthyobodo sp. II sensu Todal et al. (2004) have been detected on Atlantic salmon in both fresh- and seawater. In the present study a morphological description of Ichthyobodo sp. II from the gills of salmon reared in fresh-, brackish- and seawater is presented, using both light- and electron microscopy. Comparative morphometry show that Ichthyobodo sp. II from both freshwater and seawater displays a different cell shape, and is significantly smaller than I. necator s.s. Also, ultrastructural characteristics distinguish these two species, notably differences in the attachment region and the presence of spine-like surface projections in Ichthyobodo sp. II. Based on both unique SSU rDNA sequences and morphological characteristics, we conclude that Ichthyobodo sp. II. represents a novel species for which we propose the name Ichthyobodo salmonis sp. n. PMID:21756424

  3. Influence of fluoride on aluminum toxicity to Atlantic salmon (Salmo salar)

    Science.gov (United States)

    Hamilton, Steven J.; Haines, Terry A.

    1995-01-01

    Atlantic salmon (Salmo salar) alevins were exposed to various aluminum (0–4700 μg/L) and four fluoride (0–500 μg/L) concentrations at two pH values (5.5 and 6.5) for 4- and 30-d periods. In the 4-d tests, aluminum with fluoride was less toxic at pH 6.5 than at pH 5.5, whereas without fluoride, pH had no effect. In the 30-d test, mortality in all treatments was 17–21% at pH 5.5, but only 3–7% at pH 6.5. Fish length and weight after 30 d were reduced in all fluoride–aluminum treatments at pH 5.5, but only in the 200-μg/L aluminum without fluoride treatment at pH 6.5. At pH 5.5 and 6.5 without aluminum, histomorphological examinations revealed no abnormalities in gill tissue. However, in aluminum exposure with no fluoride, gill filaments and secondary lamellae were swollen and thickened. Addition of fluoride at pH 6.5 alleviated some gill damage. At pH 5.5 and 200 μg/L aluminum, addition of 100 μg/L fluoride reduced swelling of gill lamellae, but 200 μg/L fluoride did not reduce swelling. Low fluoride concentrations (fluoride concentrations (> 100 μg/L) may not reduce aluminum-induced effects.

  4. Development and validation of a high density SNP genotyping array for Atlantic salmon (Salmo salar)

    Science.gov (United States)

    2014-01-01

    Background Dense single nucleotide polymorphism (SNP) genotyping arrays provide extensive information on polymorphic variation across the genome of species of interest. Such information can be used in studies of the genetic architecture of quantitative traits and to improve the accuracy of selection in breeding programs. In Atlantic salmon (Salmo salar), these goals are currently hampered by the lack of a high-density SNP genotyping platform. Therefore, the aim of the study was to develop and test a dense Atlantic salmon SNP array. Results SNP discovery was performed using extensive deep sequencing of Reduced Representation (RR-Seq), Restriction site-Associated DNA (RAD-Seq) and mRNA (RNA-Seq) libraries derived from farmed and wild Atlantic salmon samples (n = 283) resulting in the discovery of > 400 K putative SNPs. An Affymetrix Axiom® myDesign Custom Array was created and tested on samples of animals of wild and farmed origin (n = 96) revealing a total of 132,033 polymorphic SNPs with high call rate, good cluster separation on the array and stable Mendelian inheritance in our sample. At least 38% of these SNPs are from transcribed genomic regions and therefore more likely to include functional variants. Linkage analysis utilising the lack of male recombination in salmonids allowed the mapping of 40,214 SNPs distributed across all 29 pairs of chromosomes, highlighting the extensive genome-wide coverage of the SNPs. An identity-by-state clustering analysis revealed that the array can clearly distinguish between fish of different origins, within and between farmed and wild populations. Finally, Y-chromosome-specific probes included on the array provide an accurate molecular genetic test for sex. Conclusions This manuscript describes the first high-density SNP genotyping array for Atlantic salmon. This array will be publicly available and is likely to be used as a platform for high-resolution genetics research into traits of evolutionary and economic importance in

  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 head was 15.0% with a biological standard deviation of 3.0%. The astaxanthin concentration was 5.5 mg/kg of muscle with a biological standard deviation of 1.1 mg/kg of muscle, and the canthaxanthin concentration was 200 mu g/kg of muscle with a standard deviation of 47 mu g/kg of muscle....... 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...

  6. 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.

  7. Dietary linoleic acid elevates endogenous 2-arachidonoylglycerol and anandamide in Atlantic salmon (Salmo salar L.) and mice, and induces weight gain and inflammation in mice

    DEFF Research Database (Denmark)

    Alvheim, Anita R.; Torstensen, Bente E.; Lin, Yu Hong

    2013-01-01

    , arachidonic acid (AA), decreased EPA and DHA, elevated the endocannabinoids 2-arachidonoylglycerol (2-AG) and anandamide (AEA), and increased TAG accumulation in the salmon liver. In mice, the SO salmon diet increased LA and AA and decreased EPA and DHA in the liver and erythrocyte phospholipids, and elevated......Dietary intake of linoleic acid (LA) has increased dramatically during the twentieth century and is associated with a greater prevalence of obesity. Vegetable oils are recognised as suitable alternatives to fish oil (FO) in feed for Atlantic salmon (Salmo salar L.) but introduce high amounts of LA......-inflammatory properties of EPA and DHA in mice....

  8. 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.

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

    Science.gov (United States)

    Minniti, Giusi; Hagen, Live Heldal; Porcellato, Davide; Jørgensen, Sven Martin; Pope, Phillip B.; Vaaje-Kolstad, Gustav

    2017-01-01

    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. PMID:29104567

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

    Directory of Open Access Journals (Sweden)

    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.

  11. Spatiotemporal dynamics of the Atlantic salmon (Salmo salar) Greenland fishery inferred from mixed-stock analysis

    Science.gov (United States)

    Gauthier-Ouellet, M.; Dionne, M.; Caron, F.; King, T.L.; Bernatchez, L.

    2009-01-01

    Mixed-stock fisheries refer to the exploitation of admixed fish stocks coming from different origins. We identified the North American origin of 2835 Atlantic salmon (Salmo salar) in the Greenland mixed-stock fishery during 11 years (1995-2006) at three localities using 13 microsatellites. The study included 52 baseline populations representing nine genetically distinct regional groups. The contribution of each group ranged from increasing contribution for Labrador (+14.9%) was observed during the time course of the study. The estimated regional contribution to the Greenland fishery was significantly correlated to the number of multi-sea-winter salmon regionally produced in 2002 (r = 0.79) and 2004 (r = 0.92). No difference in contribution was found between the three Greenland sampling localities. Ungava and Southern Qu??bec regions showed the highest mortality estimates caused by the fishery, ranging from 12.10% to 18.08%, for both years tested. No regional group was overrepresented in landings compared with their respective productivity. Yet, management precautions should still be taken as the fishery strongly selects large females, which could have evolutionary impacts on populations over the long term.

  12. 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.

  13. Lipid peroxidation analysis in salmon (Salmo salar L.) processed by e-beam

    International Nuclear Information System (INIS)

    Thomaz, Fernanda S.; Trindade, Reginaldo A.; Fanaro, Gustavo B.; Araujo, Michel M.; Villavicencio, Ana Lucia C.H.; Mancini-Filho, Jorge

    2007-01-01

    In Brazil the consumption of fish is relatively small when compared with other source of meat protein. However the diets rich in fish have association with a wide range of positive health effects, due your great deal the fat acids omega 3, EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid). Salmon (Salmo salar L.) specifically have those fat acids in main quantity. The omega 3 fat acids are related to the prevention of several not transmissible illness; with emphasis to cardiovascular, hypertriglyceridemia, cancer, osteoporosis and inflammatory and anti immune diseases. Food borne illnesses have been a growing concern to the governments, producers and consumers, mainly regarding the damages they cause to human health. In this context, irradiation is used as a method to preserve food. The present work aim to evaluate the lipid peroxidation in natura salmon filet irradiated on the basis of thiobarbituric acid reactive substances (TBARS). Samples were irradiated in an e beam accelerator (Radiation Dynamics Co. model JOB, New York, USA), 1,5 MeV-25mA at doses of 0, 1.0 and 2.0 kGy, analyzed 7, 15, 21, 30 e 45 days after irradiation. Irradiated samples analyzed during a 45 day period, showed a higher lipid peroxidation than the control samples at the same period, increasing with dose and storage time. However, it did not pass the permitted value. Irradiation demonstrated effective without compromising the quality of the food. (author)

  14. Lipid peroxidation analysis in salmon (Salmo salar L.) processed by e-beam

    Energy Technology Data Exchange (ETDEWEB)

    Thomaz, Fernanda S.; Trindade, Reginaldo A.; Fanaro, Gustavo B.; Araujo, Michel M.; Villavicencio, Ana Lucia C.H. [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)]. E-mail: villavic@ipen.br; Mancini-Filho, Jorge [Universidade de Sao Paulo (USP), Ribeirao Preto, SP (Brazil). Faculdade de Ciencias Farmaceuticas]. E-mail: jmancini@usp.br

    2007-07-01

    In Brazil the consumption of fish is relatively small when compared with other source of meat protein. However the diets rich in fish have association with a wide range of positive health effects, due your great deal the fat acids omega 3, EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid). Salmon (Salmo salar L.) specifically have those fat acids in main quantity. The omega 3 fat acids are related to the prevention of several not transmissible illness; with emphasis to cardiovascular, hypertriglyceridemia, cancer, osteoporosis and inflammatory and anti immune diseases. Food borne illnesses have been a growing concern to the governments, producers and consumers, mainly regarding the damages they cause to human health. In this context, irradiation is used as a method to preserve food. The present work aim to evaluate the lipid peroxidation in natura salmon filet irradiated on the basis of thiobarbituric acid reactive substances (TBARS). Samples were irradiated in an e beam accelerator (Radiation Dynamics Co. model JOB, New York, USA), 1,5 MeV-25mA at doses of 0, 1.0 and 2.0 kGy, analyzed 7, 15, 21, 30 e 45 days after irradiation. Irradiated samples analyzed during a 45 day period, showed a higher lipid peroxidation than the control samples at the same period, increasing with dose and storage time. However, it did not pass the permitted value. Irradiation demonstrated effective without compromising the quality of the food. (author)

  15. Study of the quality characteristics in cold-smoked salmon (Salmo salar) originating from pre- or post-rigor raw material.

    Science.gov (United States)

    Birkeland, S; Akse, L

    2010-01-01

    Improved slaughtering procedures in the salmon industry have caused a delayed onset of rigor mortis and, thus, a potential for pre-rigor secondary processing. The aim of this study was to investigate the effect of rigor status at time of processing on quality traits color, texture, sensory, microbiological, in injection salted, and cold-smoked Atlantic salmon (Salmo salar). Injection of pre-rigor fillets caused a significant (Prigor processed fillets; however, post-rigor (1477 ± 38 g) fillets had a significant (P>0.05) higher fracturability than pre-rigor fillets (1369 ± 71 g). Pre-rigor fillets were significantly (Prigor fillets (37.8 ± 0.8) and had significantly lower (Prigor processed fillets. This study showed that similar quality characteristics can be obtained in cold-smoked products processed either pre- or post-rigor when using suitable injection salting protocols and smoking techniques. © 2010 Institute of Food Technologists®

  16. 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.

  17. 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 vitamin E, hydroxyproline (HYP), liquid loss and muscle pH among all groups showed significant differences ( P important quality attributes of Atlantic salmon.

  18. 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.

  19. The effects of cortisoland actinomycin D injections on choloride cells and branchial N+---K+-ATPase in rainbow trout (Salmo gairdneri)

    Science.gov (United States)

    Eib, D.W.; Hossner, K.L.

    1985-01-01

    Injections of cortisol, actinomycin D, or combined administration of the hormone and the antiobiotic did not effect rainbow trout (Salmo gairdneri) branchial Na+K+-ATPase activity. Numbers of chloride cells also did not change following cortisol and actinomycin D treatment. These results are discussed in light of a similar report concerning Atlantic salmon (Salmo salar).

  20. Short- and long-term effects of dietary l-tryptophan supplementation on the neuroendocrine stress response in seawater-reared Atlantic salmon (Salmo salar)

    DEFF Research Database (Denmark)

    Basic, D.; Krogdahl, T.; Scholden, J.

    2013-01-01

    . Basal plasma cortisol levels were lower among non-stressed fish at 1 and 10. days post dietary Trp supplementation. By comparison, stressed fish displayed stimulatory post-stress plasma cortisol responses at 1 and 2. days after the Trp regimen was terminated. However, a reversed pattern was observed...... as well as habituation to seawater involves the neuroendocrine stress response, suggesting that such environmental factors may modulate the stress-reducing effects of Trp. To date, studies that have investigated the neuroendocrine effects of dietary Trp have only been conducted in rainbow trout...... (. Oncorhynchus mykiss), a salmonid species, under conditions featuring social isolation in the freshwater environment. Here, we address the effects of dietary Trp on post-stress plasma cortisol and hypothalamic monoamines in seawater-adapted Atlantic salmon (. Salmo salar), reared at densities relevant...

  1. Thermal and oxidative stability of Atlantic salmon oil (Salmo salar L. and complexation with β-cyclodextrin

    Directory of Open Access Journals (Sweden)

    Daniel I. Hădărugă

    2016-02-01

    Full Text Available The thermal and oxidative stability of Atlantic salmon oil (Salmo salar L. as well as its β-cyclodextrin (β-CD complexation ability has been verified for the first time. The main omega-3 fatty acids, EPA and DHA, were significantly degraded, even at 50 °C. Their relative concentrations decrease from 6.1% for EPA and 4.1% for DHA to 1.7% and 1.5% after degradation at 150 °C, respectively. On the other hand, the relative concentrations of monounsaturated and saturated fatty acids remained constant or slightly increased by a few percent after degradation (e.g., from 10.7% to 12.9% for palmitic acid. Co-crystallization of ASO with β-CD at a host–guest ratio of 1:1 and 3:1 from an ethanol–water mixture and kneading methods has been used for the preparation of β-CD/ASO complexes. The analysis of the complexes by thermogravimetry, differential scanning calorimetry (DSC, and Karl Fischer titration (KFT as well as the decrease of the “strongly-retained” water content confirm the formation of the inclusion compound. Furthermore, the DSC parameters correlate well with the KFT kinetic data for β-CD/ASO complexes.

  2. 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

    2018-03-01

    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.

  3. 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.

  4. 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.

  5. Global transcriptional analysis of short-term hepatic stress responses in Atlantic salmon (Salmo salar) exposed to depleted uranium

    Science.gov (United States)

    Song, You; Salbu, Brit; Teien, Hans-Christian; Heier, Lene Sørlie; Rosseland, Bjørn Olav; Høgåsen, Tore; Tollefsen, Knut Erik

    2014-01-01

    Potential environmental hazards of radionuclides are often studied at the individual level. Sufficient toxicogenomics data at the molecular/cellular level for understanding the effects and modes of toxic action (MoAs) of radionuclide is still lacking. The current article introduces transcriptomic data generated from a recent ecotoxicological study, with the aims to characterize the MoAs of a metallic radionuclide, deplete uranium (DU) in an ecologically and commercially important fish species, Atlantic salmon (Salmo salar). Salmon were exposed to three concentrations (0.25, 0.5 and 1.0 mg/L) of DU for 48 h. Short-term global transcriptional responses were studied using Agilent custom-designed high density 60,000-feature (60 k) salmonid oligonucleotide microarrays (oligoarray). The microarray datasets deposited at Gene Expression Omnibus (GEO ID: GSE58824) were associated with a recently published study by Song et al. (2014) in BMC Genomics. The authors describe the experimental data herein to build a platform for better understanding the toxic mechanisms and ecological hazard of radionuclides such as DU in fish. PMID:26484125

  6. Global transcriptional analysis of short-term hepatic stress responses in Atlantic salmon (Salmo salar exposed to depleted uranium

    Directory of Open Access Journals (Sweden)

    You Song

    2014-12-01

    Full Text Available Potential environmental hazards of radionuclides are often studied at the individual level. Sufficient toxicogenomics data at the molecular/cellular level for understanding the effects and modes of toxic action (MoAs of radionuclide is still lacking. The current article introduces transcriptomic data generated from a recent ecotoxicological study, with the aims to characterize the MoAs of a metallic radionuclide, deplete uranium (DU in an ecologically and commercially important fish species, Atlantic salmon (Salmo salar. Salmon were exposed to three concentrations (0.25, 0.5 and 1.0 mg/L of DU for 48 h. Short-term global transcriptional responses were studied using Agilent custom-designed high density 60,000-feature (60 k salmonid oligonucleotide microarrays (oligoarray. The microarray datasets deposited at Gene Expression Omnibus (GEO ID: GSE58824 were associated with a recently published study by Song et al. (2014 in BMC Genomics. The authors describe the experimental data herein to build a platform for better understanding the toxic mechanisms and ecological hazard of radionuclides such as DU in fish.

  7. 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.

  8. Survival of Atlantic salmon Salmo salar smolts through a hydropower complex.

    Science.gov (United States)

    Stich, D S; Bailey, M M; Zydlewski, J D

    2014-10-01

    This study evaluated Atlantic salmon Salmo salar smolt survival through the lower Penobscot River, Maine, U.S.A., and characterized relative differences in proportional use and survival through the main-stem of the river and an alternative migration route, the Stillwater Branch. The work was conducted prior to removal of two main-stem dams and operational changes in hydropower facilities in the Stillwater Branch. Survival and proportional use of migration routes in the lower Penobscot were estimated from multistate (MS) models based on 6 years of acoustic telemetry data from 1669 smolts and 2 years of radio-telemetry data from 190 fish. A small proportion (0·12, 95% c.i. = 0·06-0·25) of smolts used the Stillwater Branch, and mean survival through the two operational dams in this part of the river was relatively high (1·00 and 0·97). Survival at Milford Dam, the dam that will remain in the main-stem of the Penobscot River, was relatively low (0·91), whereas survival through two dams that were removed was relatively high (0·99 and 0·98). Smolt survival could decrease in the Stillwater Branch with the addition of two new powerhouses while continuing to meet fish passage standards. The effects of removing two dams in the main-stem are expected to be negligible for smolt survival based on high survival observed from 2005 to 2012 at those locations. Survival through Milford Dam was been well below current regulatory standards, and thus improvement of passage at this location offers the best opportunity for improving overall smolt survival in the lower river. © 2014 The Fisheries Society of the British Isles.

  9. Population transcriptomics of life-history variation in the genus Salmo

    DEFF Research Database (Denmark)

    Giger, T.; Excoffier, L.; Amstutz, U.

    2008-01-01

    with physiological changes that are likely to be involved in preadaptations to seawater in anadromous populations of the genus Salmo, one of which was identified to encode for nucleophosmin 1. Our findings thus provide new molecular insights into salmonid life-history variation, opening new perspectives in the study......In this study, we demonstrate the power of applying complementary DNA (cDNA) microarray technology to identifying candidate loci that exhibit subtle differences in expression levels associated with a complex trait in natural populations of a nonmodel organism. Using a highly replicated experimental...... design involving 180 cDNA microarray experiments, we measured gene-expression levels from 1098 transcript probes in 90 individuals originating from six brown trout (Salmo trutta) and one Atlantic salmon (Salmo salar) population, which follow either a migratory or a sedentary life history. We identified...

  10. 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 pH (5.4-5.6) and highest inorganic Al (50-80 μg·L-1). Moderate loss of plasma chloride, increased plasma cortisol and glucose, and moderately elevated gill Al occurred at less severely impacted sites. Gill Al was a better predictor of integrated physiological impacts than 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.

  11. Applying Fourier Transform Mid Infrared Spectroscopy to Detect the Adulteration of Salmo salar with Oncorhynchus mykiss

    Science.gov (United States)

    Moreira, Maria João

    2018-01-01

    The aim of this study was to evaluate the potential of Fourier transform infrared (FTIR) spectroscopy coupled with chemometric methods to detect fish adulteration. Muscles of Atlantic salmon (Salmo salar) (SS) and Salmon trout (Onconrhynchus mykiss) (OM) muscles were mixed in different percentages and transformed into mini-burgers. These were stored at 3 °C, then examined at 0, 72, 160, and 240 h for deteriorative microorganisms. Mini-burgers was submitted to Soxhlet extraction, following which lipid extracts were analyzed by FTIR. The principal component analysis (PCA) described the studied adulteration using four principal components with an explained variance of 95.60%. PCA showed that the absorbance in the spectral region from 721, 1097, 1370, 1464, 1655, 2805, to 2935, 3009 cm−1 may be attributed to biochemical fingerprints related to differences between SS and OM. The partial least squares regression (PLS-R) predicted the presence/absence of adulteration in fish samples of an external set with high accuracy. The proposed methods have the advantage of allowing quick measurements, despite the storage time of the adulterated fish. FTIR combined with chemometrics showed that a methodology to identify the adulteration of SS with OM can be established, even when stored for different periods of time. PMID:29621135

  12. 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

    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...... 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...

  13. 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 (salmon early rearing can result in improved growth performance and a lower incidence of precocious parr.

  14. Remodeling of the notochord during development of vertebral fusions in Atlantic salmon (Salmo salar).

    Science.gov (United States)

    Ytteborg, Elisabeth; Torgersen, Jacob Seilø; Pedersen, Mona E; Baeverfjord, Grete; Hannesson, Kirsten O; Takle, Harald

    2010-12-01

    Histological characterization of spinal fusions in Atlantic salmon (Salmo salar) has demonstrated shape alterations of vertebral body endplates, a reduced intervertebral space, and replacement of intervertebral cells by ectopic bone. However, the significance of the notochord during the fusion process has not been addressed. We have therefore investigated structural and cellular events in the notochord during the development of vertebral fusions. In order to induce vertebral fusions, Atlantic salmon were exposed to elevated temperatures from fertilization until they attained a size of 15g. Based on results from radiography, intermediate and terminal stages of the fusion process were investigated by immunohistochemistry and real-time quantitative polymerase chain reaction. Examination of structural extracellular matrix proteins such as Perlecan, Aggrecan, Elastin, and Laminin revealed reduced activity and reorganization at early stages in the pathology. Staining for elastic fibers visualized a thinner elastic membrane surrounding the notochord of developing fusions, and immunohistochemistry for Perlecan showed that the notochordal sheath was stretched during fusion. These findings in the outer notochord correlated with the loss of Aggrecan- and Substance-P-positive signals and the further loss of vacuoles from the chordocytes in the central notochord. At more progressed stages of fusion, chordocytes condensed, and the expression of Aggrecan and Substance P reappeared. The hyperdense regions seem to be of importance for the formation of notochordal tissue into bone. Thus, the remodeling of notochord integrity by reduced elasticity, structural alterations, and cellular changes is probably involved in the development of vertebral fusions.

  15. The complete genome sequence of CrRV-Ch01, a new member of the family Rhabdoviridae in the parasitic copepod Caligus rogercresseyi present on farmed Atlantic salmon (Salmo salar) in Chile.

    Science.gov (United States)

    Økland, Arnfinn Lodden; Skoge, Renate Hvidsten; Nylund, Are

    2018-06-01

    We have determined the complete genome sequence of a new rhabdovirus, tentatively named Caligus rogercresseyi rhabdovirus Ch01 (CrRV-Ch01), which was found in the parasite Caligus rogercresseyi, present on farmed Atlantic salmon (Salmo salar) in Chile. The genome encodes the five canonical rhabdovirus proteins in addition to an unknown protein, in the order N-P-M-U (unknown)-G-L. Phylogenetic analysis showed that the virus clusters with two rhabdoviruses (Lepeophtheirus salmonis rhabdovirus No9 and Lepeophtheirus salmonis rhabdovirus No127) obtained from another parasitic caligid, Lepeophtheirus salmonis, present on farmed Atlantic salmon on the west coast of Norway.

  16. A comparison of neutral and immune genetic variation in Atlantic salmon, Salmo salar L. in Chilean aquaculture facilities.

    Directory of Open Access Journals (Sweden)

    David S Portnoy

    Full Text Available Genetic diversity was assessed in samples of cultured Atlantic salmon, Salmo salar L., obtained from facilities in Chile between 2005 and 2010, a period of time during which the infectious pathogens Infectious Salmon Anemia (ISA virus, Caligus rogercresseyi (sea lice, and Piscirickettsia salmonis (salmon rickettsial syndrome were common. Two panels of microsatellite markers were utilized: one with microsatellites with no known gene associations (neutral and one featuring microsatellites linked to putative immune-related genes (immune-related. Allelic richness and gene diversity across samples were significantly greater in neutral loci as compared to immune-related loci. Both diversity measures were homogeneous among samples for immune-related loci and heterogeneous among samples for neutral loci. Immune-related loci were identified as F(ST outliers in pairwise comparisons of samples at a 10-fold higher frequency than neutral loci. These results indicate that neutral and immune-related portions of the Atlantic salmon genome may have differed in response to the gauntlet of pathogens and that monitoring of specific, well characterized immune-related loci as well as neutral loci in cultured species could be useful when disease control and prevention is a goal.

  17. 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...

  18. 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...... administration of OXA. A numerical description of the concentration of the antimicrobial agent achieved in therapy is necessary to determine the resistance or sensitivity of the bacteria involved in the infection. The degree of fish-to-fish variation in the concentrations of OXA, both within the healthy fish...... a useful parameter for describing the concentrations of agents achieved during therapy. The plasma data from this investigation were used to estimate clinically relevant breakpoint minimum inhibitory concentration (MIC) values. The validity of these breakpoint values was discussed with reference...

  19. 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.

  20. 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.

  1. 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

    DEFF Research Database (Denmark)

    Vaz-Serrano, J.; Ruiz-Gomez, M. L.; Gjøen, H. M.

    2011-01-01

    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......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...... 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...

  2. Mate choice for major histocompatibility complex genetic divergence as a bet-hedging strategy in the Atlantic salmon (Salmo salar)

    Science.gov (United States)

    Evans, Melissa L.; Dionne, Mélanie; Miller, Kristina M.; Bernatchez, Louis

    2012-01-01

    Major histocompatibility complex (MHC)-dependent mating preferences have been observed across vertebrate taxa and these preferences are expected to promote offspring disease resistance and ultimately, viability. However, little empirical evidence linking MHC-dependent mate choice and fitness is available, particularly in wild populations. Here, we explore the adaptive potential of previously observed patterns of MHC-dependent mate choice in a wild population of Atlantic salmon (Salmo salar) in Québec, Canada, by examining the relationship between MHC genetic variation and adult reproductive success and offspring survival over 3 years of study. While Atlantic salmon choose their mates in order to increase MHC diversity in offspring, adult reproductive success was in fact maximized between pairs exhibiting an intermediate level of MHC dissimilarity. Moreover, patterns of offspring survival between years 0+ and 1+, and 1+ and 2+ and population genetic structure at the MHC locus relative to microsatellite loci indicate that strong temporal variation in selection is likely to be operating on the MHC. We interpret MHC-dependent mate choice for diversity as a likely bet-hedging strategy that maximizes parental fitness in the face of temporally variable and unpredictable natural selection pressures. PMID:21697172

  3. Toxicity of road deicing salt (NaCl) and copper (Cu) to fertilization and early developmental stages of Atlantic salmon (Salmo salar).

    Science.gov (United States)

    Mahrosh, Urma; Kleiven, Merethe; Meland, Sondre; Rosseland, Bjørn Olav; Salbu, Brit; Teien, Hans-Christian

    2014-09-15

    In many countries, salting of ice or snow covered roads may affect aquatic organisms in the catchment directly or indirectly by mobilization of toxic metals. We studied the toxicity of road deicing salt and copper (Cu) on the vulnerable early life stages of Atlantic salmon (Salmo salar), from fertilization till hatching. Controlled episodic exposure to road salt (≥ 5,000 mg/L) during fertilization resulted in reduced swelling and less percent egg survival. Exposure to Cu both during and post fertilization caused delayed hatching. Larval deformities were, however found as an additional effect, when eggs were exposed to high salt concentration (≥ 5,000 mg/L) mixed with Cu (10 μg Cu/L) during fertilization. Thus, it appears that the sensitivity of early developmental stages of Atlantic salmon increased when exposed to these stressors, and road salt application during spawning can pose threat to Atlantic salmon in water bodies receiving road runoff. The study gives insight on assessment and management of risks on Atlantic salmon population posed by road related hazardous chemicals. Copyright © 2014 Elsevier B.V. All rights reserved.

  4. 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.

  5. Identification and characterisation of TLR18-21 genes in Atlantic salmon (Salmo salar).

    Science.gov (United States)

    Lee, P T; Zou, J; Holland, J W; Martin, S A M; Collet, B; Kanellos, T; Secombes, C J

    2014-12-01

    Teleost fish possess many types of toll-like receptor (TLR) some of which exist in other vertebrate groups and some that do not (ie so-called "fish-specific" TLRs). In this study, we identified in Atlantic salmon (Salmo salar) whole-genome shotgun (WGS) contigs seven TLRs that are not found in mammals, including six types of fish-specific TLRs (one TLR18, one TLR19, and four TLR20 members (two of which are putative soluble forms (s)) and one TLR21. Phylogenetic analysis revealed that teleost TLR19-21 are closely related with murine TLR11-TLR13, whilst teleost TLR18 groups with mammalian TLR1, 2, 6 and 10. A typical TLR protein domain structure was found in all these TLRs with the exception of TLR20b(s) and TLR20c(s). TLR-GFP expression plasmids transfected into SHK-1 cells showed that salmon TLR19, TLR20a and TLR20d were preferentially localised to the intracellular compartment. Real time PCR analysis suggested that salmon TLR19-TLR21 are mainly expressed in immune related organs, such as spleen, head kidney and gills, while TLR18 transcripts are more abundant in muscle. In vitro stimulation of primary head kidney cells with type I IFN, IFNγ and IL-1β had no impact on TLR expression. Infectious salmon anaemia virus (ISAV) infection, in vivo, down-regulated TLR20a, TLR20b(s), TLR20d and TLR21 in infected salmon kidney tissue. In contrast, up-regulation of TLR19 and TLR20a expression was found in posterior kidney in rainbow trout with clinical proliferative kidney disease (PKD). Copyright © 2014 Elsevier Ltd. All rights reserved.

  6. 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.

  7. 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.

  8. Sublethal effects in Atlantic salmon (Salmo salar) exposed to mixtures of copper, aluminium and gamma radiation

    International Nuclear Information System (INIS)

    Heier, Lene Sørlie; Teien, Hans Christian; Oughton, Deborah; Tollefsen, Knut-Erik; Olsvik, Pål A.; Rosseland, Bjørn Olav; Lind, Ole Christian; Farmen, Eivind; Skipperud, Lindis; Salbu, Brit

    2013-01-01

    The present study was designed to investigate the effects in presmolt of Atlantic salmon (Salmo salar) exposed to copper (Cu), aluminium (Al) and gamma radiation, individually or in combination. Fish were exposed for 48 h to metals added to lake water; 10, 40 and 80 μg Cu/L, 250 μg Al/L and a combination of 40 μg Cu/L and 250 μg Al/L. In addition, gamma radiation (4–70 mGy delivered over 48 h) was added as an additional exposure stressor. Selected endpoints were chosen to reveal different toxic mechanisms and included Cu and Al accumulation on gills, blood chemistry and haematological variables (plasma sodium and chloride, haematocrit, glucose), hepatic levels of reduced and oxidised glutathione (GSH and GSSG) and hepatic transcriptional response of glutathione peroxidase (GPx), gamma-glutamylcysteine synthetase (GCS), metallothionein (MT) and ubiquitin. Exposure to Cu alone resulted in gill accumulation of Cu, reduction of plasma ions and increased transcriptional response of GPx, MT and ubiquitin. Exposure to Al alone reduced plasma ion levels but did not affect any of the hepatic biomarkers except for ubiquitin. The combined metal exposure (Cu + Al) altered the GSH levels, however GPx and MT were not affected suggesting a different mode of detoxification in the combined exposure. Gamma radiation appeared to influence GSH and ubiquitin levels. The observed effects seemed to be both stressor and concentration dependent

  9. Gill pathology in Scottish farmed Atlantic salmon, Salmo salar L., associated with the microsporidian Desmozoon lepeophtherii Freeman et Sommerville, 2009.

    Science.gov (United States)

    Matthews, C G G; Richards, R H; Shinn, A P; Cox, D I

    2013-10-01

    Gill disorders have emerged in recent years as a significant problem in the production of marine-stage Atlantic salmon Salmo salar L. The multi-aetiological condition 'proliferative gill inflammation' (PGI) has been reported to cause heavy losses in western Norway, yet reports of Scottish cases of the disease have remained anecdotal. In the present study, histopathological material from a marine production site in the Scottish Highlands experiencing mortalities due to a seasonal gill disease with proliferative-type pathology was examined using light microscopy, special staining techniques and transmission electron microscopy (TEM). The microsporidian Desmozoon lepeophtherii Freeman et Sommerville, 2009 (syn. Paranucleospora theridion) was identified by staining using a Gram Twort method and TEM associated with distinctive proliferative and necrotic pathology confined to the interlamellar Malpighian cell areas of the primary filaments. Epitheliocystis was not a feature of the gill pathology observed. It is believed this is the first report of D. lepeophtherii being identified associated with pathology in a Scottish gill disease case, and supports anecdotal reports that a disease at least partly synonymous with PGI as described by Norwegian researchers is present in Scottish aquaculture. © 2013 John Wiley & Sons Ltd.

  10. 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.

  11. 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

  12. Hepatic transcriptional responses in Atlantic salmon (Salmo salar) exposed to gamma radiation and depleted uranium singly and in combination

    International Nuclear Information System (INIS)

    Song, You; Salbu, Brit; Teien, Hans-Christian; Evensen, Øystein; Lind, Ole Christian; Rosseland, Bjørn Olav

    2016-01-01

    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. 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 (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 exercise and dissolved oxygen at saturation during Atlantic salmon early rearing can result in improved growth performance and a lower incidence of precocious parr.

  14. Intestinal Fluid Permeability in Atlantic Salmon (Salmo salar L. Is Affected by Dietary Protein Source.

    Directory of Open Access Journals (Sweden)

    Haibin Hu

    Full Text Available In Atlantic salmon (Salmo salar L., and also in other fish species, certain plant protein ingredients can increase fecal water content creating a diarrhea-like condition which may impair gut function and reduce fish growth. The present study aimed to strengthen understanding of the underlying mechanisms by observing effects of various alternative plant protein sources when replacing fish meal on expression of genes encoding proteins playing key roles in regulation of water transport across the mucosa of the distal intestine (DI. A 48-day feeding trial was conducted with five diets: A reference diet (FM in which fish meal (72% was the only protein source; Diet SBMWG with a mix of soybean meal (30% and wheat gluten (22%; Diet SPCPM with a mix of soy protein concentrate (30% and poultry meal (6%; Diet GMWG with guar meal (30% and wheat gluten (14.5%; Diet PM with 58% poultry meal. Compared to fish fed the FM reference diet, fish fed the soybean meal containing diet (SBMWG showed signs of enteritis in the DI, increased fecal water content of DI chyme and higher plasma osmolality. Altered DI expression of a battery of genes encoding aquaporins, ion transporters, tight junction and adherens junction proteins suggested reduced transcellular transport of water as well as a tightening of the junction barrier in fish fed the SBMWG diet, which may explain the observed higher fecal water content and plasma osmolality. DI structure was not altered for fish fed the other experimental diets but alterations in target gene expression and fecal water content were observed, indicating that alterations in water transport components may take place without clear effects on intestinal structure.

  15. Atlantic salmon, Salmo salar L. are broadly susceptible to isolates representing the North American genogroups of infectious hematopoietic necrosis virus

    Science.gov (United States)

    Kurath, Gael; Winton, James R.; Dale, Ole B.; Purcell, Maureen K.; Falk, Knut; Busch, Robert D.

    2016-01-01

    Beginning in 1992, three epidemic waves of infectious hematopoietic necrosis, often with high mortality, occurred in farmed Atlantic salmon Salmo salar L. on the west coast of North America. We compared the virulence of eleven strains of infectious hematopoietic necrosis virus (IHNV), representing the U, M and L genogroups, in experimental challenges of juvenile Atlantic salmon in freshwater. All strains caused mortality and there was wide variation within genogroups: cumulative mortality for five U-group strains ranged from 20 to 100%, four M-group strains ranged 30-63% and two L-group strains varied from 41 to 81%. Thus, unlike Pacific salmonids, there was no apparent correlation of virulence in a particular host species with virus genogroup. The mortality patterns indicated two different phenotypes in terms of kinetics of disease progression and final per cent mortality, with nine strains having moderate virulence and two strains (from the U and L genogroups) having high virulence. These phenotypes were investigated by histopathology and immunohistochemistry to describe the variation in the course of IHNV disease in Atlantic salmon. The results from this study demonstrate that IHNV may become a major threat to farmed Atlantic salmon in other regions of the world where the virus has been, or may be, introduced.

  16. Variation in wind and piscivorous predator fields affecting the survival of Atlantic salmon, Salmo salar, in the Gulf of Maine

    Science.gov (United States)

    Friedland, K.D.; Manning, J.P.; Link, Jason S.; Gilbert, J.R.; Gilbert, A.T.; O'Connell, A.F.

    2012-01-01

    Observations relevant to the North American stock complex of Atlantic salmon, Salmo salar L., suggest that marine mortality is influenced by variation in predation pressure affecting post-smolts during the first months at sea. This hypothesis was tested for Gulf of Maine (GOM) stocks by examining wind pseudostress and the distribution of piscivorous predator fields potentially affecting post-smolts. Marine survival has declined over recent decades with a change in the direction of spring winds, which is likely extending the migration of post-smolts by favouring routes using the western GOM. In addition to changes in spring wind patterns, higher spring sea surface temperatures have been associated with shifting distributions of a range of fish species. The abundance of several pelagic piscivores, which based on their feeding habits may predate on salmon post-smolts, has increased in the areas that serve as migration corridors for post-smolts. In particular, populations of silver hake, Merluccius bilinearis (Mitchell), red hake, Urophycis chuss (Walbaum), and spiny dogfish, Squalus acanthias L., increased in size in the portion of the GOM used by post-smolts. Climate variation and shifting predator distributions in the GOM are consistent with the predator hypothesis of recruitment control suggested for the stock complex.

  17. 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.

  18. Associations between piscine reovirus infection and life history traits in wild-caught Atlantic salmon Salmo salar L. in Norway.

    Science.gov (United States)

    Garseth, Ase Helen; Biering, Eirik; Aunsmo, Arnfinn

    2013-10-01

    Piscine Reovirus (PRV), the putative causative agent of heart and skeletal muscle inflammation (HSMI), is widely distributed in both farmed and wild Atlantic salmon (Salmo salar L.) in Norway. While HSMI is a common and commercially important disease in farmed Atlantic salmon, the presence of PRV has so far not been associated with HSMI related lesions in wild salmon. Factors associated with PRV-infection were investigated in returning Atlantic salmon captured in Norwegian rivers. A multilevel mixed-effect logistic regression model confirmed clustering within rivers and demonstrated that PRV-infection is associated with life-history, sex, catch-year and body length as a proxy for sea-age. Escaped farmed salmon (odds ratio/OR: 7.32, p<0.001) and hatchery-reared salmon (OR: 1.69 p=0.073) have higher odds of being PRV-infected than wild Atlantic salmon. Male salmon have double odds of being PRV infected compared to female salmon (OR: 2.11, p<0.001). Odds of being PRV-infected increased with body-length measured as decimetres (OR: 1.20, p=0.004). Since body length and sea-age are correlated (r=0.85 p<0.001), body length serves as a proxy for sea-age, meaning that spending more years in sea increases the odds of being PRV-infected. Copyright © 2013 The Author. Published by Elsevier B.V. All rights reserved.

  19. 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

  20. 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.

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

    Directory of Open Access Journals (Sweden)

    Tacchi Luca

    2012-08-01

    Full Text Available Abstract Background 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. Results 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. Conclusions The PP

  2. 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.

  3. Assessing the sensitivity of Atlantic salmon (Salmo salar) to dietary endosulfan exposure using tissue biochemistry and histology

    International Nuclear Information System (INIS)

    Glover, Chris N.; Petri, Dietrich; Tollefsen, Knut-Erik; Jorum, Nanne; Handy, Richard D.; Berntssen, Marc H.G.

    2007-01-01

    The incorporation of plant-based ingredients, and the possible carry-over of pesticides such as endosulfan, in fish feeds may present new toxicological challenges to aquacultural species. Biological responses of Atlantic salmon (Salmo salar) to a 35-day dietary endosulfan exposure at levels ranging from 4 to 710 μg kg -1 were assessed using tissue histology and biochemistry. Liver 7-ethoxyresorufin-O-deacetylase (EROD) activity was significantly elevated in the highest exposure group (710 μg kg -1 ) by day 35. Other hepatic indicators of stress impacts and responses (glutathione-S-transferase and glutathione peroxidase activities and hepatic α-tocopherol content) remained unchanged. Branchial Na + , K + -ATPase activity was significantly reduced at day 14 in the highest exposure group, but returned to control levels by day 35. Conversely, intestinal Na + , K + -ATPase activity was significantly inhibited at day 35, but again only at the highest exposure level. In contrast to the biochemical results, hepatic and intestinal histology revealed effects of exposure even at the lowest dose tested (4 μg kg -1 ). In the posterior intestine, pathology was characterised by vacuolation and fusion of villi, and in the most severe cases, loss of epithelial integrity in villi tips. In the liver the primary effects were glycogen depletion and lipidosis. These changes were typical of a generalised stress response. While histology endpoints may prove to be the most sensitive indicators of dietary endosulfan exposure, the organismal relevance of these structural changes must be considered in the absence of effects in other biomarkers at dietary levels less than 710 μg kg -1

  4. Biochemical and Physiological Responses in Atlantic Salmon (Salmo salar) Following Dietary Exposure to Copper and Cadmium

    International Nuclear Information System (INIS)

    Lundebye, A.-K.; Berntssen, M.H.G.; Bonga, S.E.Wendelaar; Maage, A.

    1999-01-01

    Three experiments were conducted with Atlantic salmon (Salmo salar) to assess the effects of dietary exposure to copper and cadmium. The results presented here provide an overview, details of each experiment will be published in full elsewhere. In the first experiment, salmon parr exposed for four weeks to 35 and 700 mg Cu kg -1 diet had significantly elevated intestinal copper concentrations, cell proliferation (PCNA) and apoptosis rates compared to control fish. No differences were observed in gill or plasma copper concentrations among the groups. In contrast to the controls, the Cu exposed groups did not grow significantly during the exposure period. The second experiment (three months exposure) was conducted to assess the effects of dietary copper (control, 35, 500, 700, 900 or 1750 mg Cu kg -1 diet) on growth and feed utilization in salmon fingerlings. Growth was significantly reduced after three months exposure to dietary Cu concentrations above 500 mg kg -1 . Similarly, copper body burdens were significantly higher in fish exposed to elevated dietary copper concentrations (above 35 mg Cu kg -1 diet). In the third experiment, salmon parr were exposed to one of six dietary cadmium concentrations (0, 0.5, 5, 25, 125 or 250 mg Cd kg -1 diet) for four months. Cadmium accumulated in the liver>intestine>gills of exposed fish. Rates of apoptosis and cell proliferation in the intestine increased following exposure to dietary cadmium. Exposure to elevated concentrations of dietary cadmium had no effect on growth in salmon parr. Results from these studies indicate that cellular biomarkers have potential as early warning signs of negative effects on the overall fitness of an organism

  5. Comparison of sperm motility subpopulation structure among wild anadromous and farmed male Atlantic salmon (Salmo salar) parr using a CASA system.

    Science.gov (United States)

    Caldeira, Carina; García-Molina, Almudena; Valverde, Anthony; Bompart, Daznia; Hassane, Megan; Martin, Patrick; Soler, Carles

    2018-04-13

    Atlantic salmon (Salmo salar) is an endangered freshwater species that needs help to recover its wild stocks. However, the priority in aquaculture is to obtain successful fertilisation and genetic variability to secure the revival of the species. The aims of the present work were to study sperm subpopulation structure and motility patterns in wild anadromous males and farmed male Atlantic salmon parr. Salmon sperm samples were collected from wild anadromous salmon (WS) and two generations of farmed parr males. Sperm samples were collected from sexually mature males and sperm motility was analysed at different times after activation (5 and 35s). Differences among the three groups were analysed using statistical techniques based on Cluster analysis the Bayesian method. Atlantic salmon were found to have three sperm subpopulations, and the spermatozoa in ejaculates of mature farmed parr males had a higher velocity and larger size than those of WS males. This could be an adaptation to high sperm competition because salmonid species are naturally adapted to this process. Motility analysis enables us to identify sperm subpopulations, and it may be useful to correlate these sperm subpopulations with fertilisation ability to test whether faster-swimming spermatozoa have a higher probability of success.

  6. Selective precipitation reaction: a novel diagnostic test for tissue pathology in Atlantic salmon, Salmo salar, infected with salmonid alphavirus (SAV3).

    Science.gov (United States)

    Braceland, M; Tinsley, J; Cockerill, D; Bickerdike, R; McLoughlin, M F; Eckersall, P D

    2017-08-01

    While investigating biomarkers for infection with salmonid alphavirus (SAV), the cause of pancreas disease (PD), a selective precipitation reaction (SPR) has been discovered in serum which could be an on-farm qualitative test and an in-laboratory quantitative assay for health assessments in aquaculture. Mixing serum from Atlantic salmon, Salmo salar, with SAV infection with a sodium acetate buffer caused a visible precipitation which does not occur with serum from healthy salmon. Proteomic examination of the precipitate has revealed that the components are a mix of muscle proteins, for example enolase and aldolase, along with serum protein such as serotransferrin and complement C9. The assay has been optimized for molarity, pH, temperature and wavelength so that the precipitation can be measured as the change in optical density at 340 nm (Δ 340 ). Application of the SPR assay to serum samples from a cohabitation trial of SAV infection in salmon showed that the Δ 340 in infected fish rose from undetectable to a maximum at 6 weeks post-infection correlating with histopathological score of pancreas, heart and muscle damage. This test may have a valuable role to play in the diagnostic evaluation of stock health in salmon. © 2016 The Authors. Journal of Fish Diseases Published by John Wiley & Sons Ltd.

  7. Efficacy of emamectin benzoate against sea lice infestations of Atlantic salmon, Salmo salar L.: evaluation in the absence of an untreated contemporary control.

    Science.gov (United States)

    Gustafson, L; Ellis, S; Robinson, T; Marenghi, F; Endris, R

    2006-10-01

    The efficacy of emamectin benzoate (SLICE) against sea lice infestations of Atlantic salmon, Salmo salar L., is typically assessed using untreated fish, or fish treated with alternative therapeutants, as controls. The State of Maine, USA, is currently under active management for the OIE-notifiable pathogen, infectious salmon anaemia virus (ISAV); consequently, neither control group is feasible in this region. Untreated salmon risk extensive damage from the ectoparasites, and threaten to increase vector-borne exposure or susceptibility of farms to ISAV; and the only treatment presently available in Maine is SLICE. However, because sea lice infestations are unlikely to resolve spontaneously, and response to treatment occurs within weeks, use of a pretreatment baseline is a reasonable alternative for confirmatory studies. We evaluated SLICE efficacy on Atlantic salmon farms in Cobscook Bay 2002-2005, in the absence of untreated controls, using pretreatment lice loads as a reference for calculation. Maximum efficacy ranged from 68% to 100% reduction from initial levels. Time-to-maximum efficacy ranged from 1 to 8 weeks after treatment initiation. Efficacy duration, measured between first reduction and first progressive rise in counts, ranged from 4 to 16 weeks.

  8. Tentative de réacclimatation de Salmo salar dans le bassin de la Bresle (Normandie, France

    Directory of Open Access Journals (Sweden)

    ARRIGNON J.

    2008-09-01

    Full Text Available La BRESLE, rivière séparant la Haute-Normandie de la Picardie, dans le Nord-Ouest de la France était occasionnellement fréquentée jusqu'en 1964 par le saumon de lAtlantique, Salmo Salar. Le Conseil Supérieur de la Pêche a décidé de diriger l'essentiel des moyens consacrés à cette région à la réacclimatation du saumon, à l'« ensaumonnement » de ce cours d'eau. Le choix a été opéré en fonction de la situation hydrographique, hydraulique et hydrobiologique de la rivière. Les travaux ont porté sur la lutte contre la pollution sévissant dans la basse vallée, la lutte contre le braconnage, l'amélioration du milieu aquatique : franchissement d'obstacles à la remontée des salmonidés migrateurs, ameublissement des frayères, enlèvement des prédateurs. Ils ont également porté sur des introductions annuelles d'environ 100.000 oeufs de saumons à des stades divers. Les résultats montrent que le nombre des smolts s'accroît, de même que, en 1972, le nombre des adultes contrôlés et marqués lors de leurs déplacements. Le nombre modeste des uns et des autres ainsi que le caractère récent de cette réapparition du saumon en Bresle ne permettent pas de dire qu'il y a réacclimatation de l'espèce : il s'agit d'un simple indice favorable à la réacclimatation du saumon. L'auteur conclut en pensant que la truite de mer présente dans les cours d'eau de cette région un intérêt supérieur à celui du Saumon mais que, dans le cas particulier de la rivière la BRESLE, l'introduction du saumon est une initiative intéressante pour les pêcheurs sportifs. Il conviendra toutefois de grossir considérablement l'ensaumonnement en introduisant davantage de smolts. Il sera également important de prévoir une réglementation de la pêche assurant le maintien de l'installation du saumon dans cette rivière. The Bresle river, running between upper Normandy and Picardy in the North-Western part of France, saw occasional runs of

  9. Development of intestinal ion-transporting mechanisms during smoltification and seawater acclimation in Atlantic salmon Salmo salar

    Science.gov (United States)

    Sundh, Henrik; Nilsen, Tom O.; Lindström, Jenny; Hasselberg-Frank, Linda; Stefansson, Sigurd O.; McCormick, Stephen D.; Sundell, K.

    2014-01-01

    This study investigated the expression of ion transporters involved in intestinal fluid absorption and presents evidence for developmental changes in abundance and tissue distribution of these transporters during smoltification and seawater (SW) acclimation of Atlantic salmonSalmo salar. Emphasis was placed on Na+, K+-ATPase (NKA) and Na+, K+, Cl− co-transporter (NKCC) isoforms, at both transcriptional and protein levels, together with transcription of chloride channel genes. The nka α1c was the dominant isoform at the transcript level in both proximal and distal intestines; also, it was the most abundant isoform expressed in the basolateral membrane of enterocytes in the proximal intestine. This isoform was also abundantly expressed in the distal intestine in the lower part of the mucosal folds. The protein expression of intestinal Nkaα1c increased during smoltification. Immunostaining was localized to the basal membrane of the enterocytes in freshwater (FW) fish, and re-distributed to a lateral position after SW entry. Two other Nka isoforms, α1a and α1b, were expressed in the intestine but were not regulated to the same extent during smoltification and subsequent SW transfer. Their localization in the intestinal wall indicates a house-keeping function in excitatory tissues. The absorptive form of the NKCC-like isoform (sub-apically located NKCC2 and/or Na+, Cl−co-transporter) increased during smoltification and further after SW transfer. The cellular distribution changed from a diffuse expression in the sub-apical regions during smoltification to clustering of the transporters closer to the apical membrane after entry to SW. Furthermore, transcript abundance indicates that the mechanisms necessary for exit of chloride ions across the basolateral membrane and into the lateral intercellular space are present in the form of one or more of three different chloride channels: cystic fibrosis transmembrane conductance regulator I and II and chloride channel

  10. Differential response of continental stock complexes of Atlantic salmon (Salmo salar) to the Atlantic Multidecadal Oscillation

    Science.gov (United States)

    Friedland, Kevin D.; Shank, Burton V.; Todd, Christopher D.; McGinnity, Philip; Nye, Janet A.

    2014-05-01

    Atlantic salmon, Salmo salar, in the North Atlantic are managed as a set of population complexes distributed in North America and Europe. In recent years, these complexes have experienced reduced marine survival and many populations within the complexes are at risk, especially those at the southern ends of the species amphi-Atlantic range. Atlantic salmon is an anadromous fish dividing its life history between residence in freshwater and the marine environment. The freshwater portion of the life history includes spawning and the rearing of juveniles where in-river production has tended to be relatively stable, whereas the first year at sea, termed the post-smolt year, is characterized by more variable rates of mortality. Although their habitats are widely separated geographically along the North Atlantic seaboards, strong recruitment coherence exists between North American and European stock complexes. This recruitment coherence is correlated with ocean temperature variation associated with the Atlantic Multidecadal Oscillation (AMO). The North Atlantic Oscillation (NAO) appears to be relatively unimportant as a driver of salmon abundance. The mechanism determining the link between AMO-related thermal variation and abundance appears to differ fundamentally for the two continental stock groupings. Whereas ocean climate variability during the first springtime months of juvenile salmon migration to sea appears to be important to the survival of North American stocks, summer climate variation appears to be central to adult recruitment variation for European stocks. This contrast in seasonal effects appears to be related to the varying roles of predation pressure and size-related mortality on the continental stock complexes. The anticipated warming due to global climate change will impose thermal conditions on salmon populations outside historical context and challenge the ability of many populations to persist.

  11. 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.

  12. Pharmacokinetics and transcriptional effects of the anti-salmon lice drug emamectin benzoate in Atlantic salmon (Salmo salar L.).

    Science.gov (United States)

    Olsvik, Pål A; Lie, Kai K; Mykkeltvedt, Eva; Samuelsen, Ole B; Petersen, Kjell; Stavrum, Anne-Kristin; Lunestad, Bjørn T

    2008-09-11

    Emamectin benzoate (EB) is a dominating pharmaceutical drug used for the treatment and control of infections by sea lice (Lepeophtheirus salmonis) on Atlantic salmon (Salmo salar L). Fish with an initial mean weight of 132 g were experimentally medicated by a standard seven-day EB treatment, and the concentrations of drug in liver, muscle and skin were examined. To investigate how EB affects Atlantic salmon transcription in liver, tissues were assessed by microarray and qPCR at 7, 14 and 35 days after the initiation of medication. The pharmacokinetic examination revealed highest EB concentrations in all three tissues at day 14, seven days after the end of the medication period. Only modest effects were seen on the transcriptional levels in liver, with small fold-change alterations in transcription throughout the experimental period. Gene set enrichment analysis (GSEA) indicated that EB treatment induced oxidative stress at day 7 and inflammation at day 14. The qPCR examinations showed that medication by EB significantly increased the transcription of both HSP70 and glutathione-S-transferase (GST) in liver during a period of 35 days, compared to un-treated fish, possibly via activation of enzymes involved in phase II conjugation of metabolism in the liver. This study has shown that a standard seven-day EB treatment has only a modest effect on the transcription of genes in liver of Atlantic salmon. Based on GSEA, the medication seems to have produced a temporary oxidative stress response that might have affected protein stability and folding, followed by a secondary inflammatory response.

  13. Metabolism, health and fillet nutritional quality in Atlantic salmon (Salmo salar) fed diets containing n-3-rich microalgae.

    Science.gov (United States)

    Kousoulaki, Katerina; Østbye, Tone-Kari Knutsdatter; Krasnov, Aleksei; Torgersen, Jacob Seilø; Mørkøre, Turid; Sweetman, John

    2015-01-01

    Microalgae, as primary producers of EPA and DHA, are among the most prominent alternative sources to fish oil for n-3 long-chain PUFA in animal and human nutrition. The present study aimed to assess technical, nutritional and fish health aspects of producing n-3-rich Atlantic salmon (Salmo salar) fish fillets by dietary supplementation of increasing levels of a DHA-producing Schizochytrium sp. and reduced or without use of supplemental fish oil. Atlantic salmon smolt were fed diets with graded levels of microalgae for 12 weeks, during which all fish showed high feed intake rates with postprandial plasma leptin levels inversely correlating with final mean fish body weights. Fish performance was optimal in all experimental treatments (thermal growth coefficient about 4·0 and feed conversion ratio 0·8-0·9), protein digestibility was equal in all diets, whereas dietary lipid digestibility inversely correlated with the dietary levels of the SFA 16 : 0. Fillet quality was good and similar to the control in all treatments in terms of n-3 long-chain PUFA content, gaping, texture and liquid losses during thawing. Histological fluorescence staining and immunofluorescence analysis of salmon intestines (midgut: base of intestine and villi) revealed significant effects on slime, goblet cell production and inducible nitric oxide synthase (iNOS) activity with increasing levels of dietary Schizochytrium sp. supplementation. Microarray analysis did not reveal any signs of toxicity, stress, inflammation or any other negative effects from Schizochytrium sp. supplementation in diets for Atlantic salmon.

  14. 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.

  15. Assessing the sensitivity of Atlantic salmon (Salmo salar) to dietary endosulfan exposure using tissue biochemistry and histology

    Energy Technology Data Exchange (ETDEWEB)

    Glover, Chris N.; Petri, Dietrich [National Institute of Nutrition and Seafood Research (NIFES), Bergen (Norway); Tollefsen, Knut-Erik [Norwegian Institute for Water Research (NIVA), Oslo (Norway); Jorum, Nanne [Skretting ARC, Stavanger (Norway); Handy, Richard D. [School of Biological Sciences, University of Plymouth, Plymouth (United Kingdom); Berntssen, Marc H.G. [National Institute of Nutrition and Seafood Research (NIFES), Bergen (Norway)], E-mail: marc.berntssen@nifes.no

    2007-10-15

    The incorporation of plant-based ingredients, and the possible carry-over of pesticides such as endosulfan, in fish feeds may present new toxicological challenges to aquacultural species. Biological responses of Atlantic salmon (Salmo salar) to a 35-day dietary endosulfan exposure at levels ranging from 4 to 710 {mu}g kg{sup -1} were assessed using tissue histology and biochemistry. Liver 7-ethoxyresorufin-O-deacetylase (EROD) activity was significantly elevated in the highest exposure group (710 {mu}g kg{sup -1}) by day 35. Other hepatic indicators of stress impacts and responses (glutathione-S-transferase and glutathione peroxidase activities and hepatic {alpha}-tocopherol content) remained unchanged. Branchial Na{sup +}, K{sup +}-ATPase activity was significantly reduced at day 14 in the highest exposure group, but returned to control levels by day 35. Conversely, intestinal Na{sup +}, K{sup +}-ATPase activity was significantly inhibited at day 35, but again only at the highest exposure level. In contrast to the biochemical results, hepatic and intestinal histology revealed effects of exposure even at the lowest dose tested (4 {mu}g kg{sup -1}). In the posterior intestine, pathology was characterised by vacuolation and fusion of villi, and in the most severe cases, loss of epithelial integrity in villi tips. In the liver the primary effects were glycogen depletion and lipidosis. These changes were typical of a generalised stress response. While histology endpoints may prove to be the most sensitive indicators of dietary endosulfan exposure, the organismal relevance of these structural changes must be considered in the absence of effects in other biomarkers at dietary levels less than 710 {mu}g kg{sup -1}.

  16. A SNP Based Linkage Map of the Arctic Charr (Salvelinus alpinus Genome Provides Insights into the Diploidization Process After Whole Genome Duplication

    Directory of Open Access Journals (Sweden)

    Cameron M. Nugent

    2017-02-01

    Full Text Available Diploidization, which follows whole genome duplication events, does not occur evenly across the genome. In salmonid fishes, certain pairs of homeologous chromosomes preserve tetraploid loci in higher frequencies toward the telomeres due to residual tetrasomic inheritance. Research suggests this occurs only in homeologous pairs where one chromosome arm has undergone a fusion event. We present a linkage map for Arctic charr (Salvelinus alpinus, a salmonid species with relatively fewer chromosome fusions. Genotype by sequencing identified 19,418 SNPs, and a linkage map consisting of 4508 markers was constructed from a subset of high quality SNPs and microsatellite markers that were used to anchor the new map to previous versions. Both male- and female-specific linkage maps contained the expected number of 39 linkage groups. The chromosome type associated with each linkage group was determined, and 10 stable metacentric chromosomes were identified, along with a chromosome polymorphism involving the sex chromosome AC04. Two instances of a weak form of pseudolinkage were detected in the telomeric regions of homeologous chromosome arms in both female and male linkage maps. Chromosome arm homologies within the Atlantic salmon (Salmo salar and rainbow trout (Oncorhynchus mykiss genomes were determined. Paralogous sequence variants (PSVs were identified, and their comparative BLASTn hit locations showed that duplicate markers exist in higher numbers on seven pairs of homeologous arms, previously identified as preserving tetrasomy in salmonid species. Homeologous arm pairs where neither arm has been part of a fusion event in Arctic charr had fewer PSVs, suggesting faster diploidization rates in these regions.

  17. 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.

  18. Uptake and effects of 2, 4, 6 - trinitrotoluene (TNT) in juvenile Atlantic salmon (Salmo salar).

    Science.gov (United States)

    Mariussen, Espen; Stornes, Siv Marie; Bøifot, Kari Oline; Rosseland, Bjørn Olav; Salbu, Brit; Heier, Lene Sørlie

    2018-01-01

    Organ specific uptake and depuration, and biological effects in Atlantic salmon (Salmo salar) exposed to 2, 4, 6-trinitrotoluene (TNT) were studied. Two experiments were conducted, the first using radiolabeled TNT ( 14 C-TNT, 0.16mg/L) to study uptake (48h) and depuration (48h), while the second experiment focused on physiological effects in fish exposed to increasing concentrations of unlabeled TNT (1μg-1mg/L) for 48h. The uptake of 14 C-TNT in the gills and most of the organs increased rapidly during the first 6h of exposure (12h in the brain) followed by a rapid decrease even though the fish were still exposed to TNT in the water. The radioactivity in the gall bladder reached a maximum after 55h, 7h after the transfer to the clean water. A high concentration of 14 C-TNT in the gall bladder indicates that TNT is excreted through the gall bladder. Mortality (2 out of 14) was observed at a concentration of 1mg/L, and the surviving fish had hemorrhages in the dorsal muscle tissue near the spine. Analysis of the physiological parameters in blood from the high exposure group revealed severe effects, with an increase in the levels of glucose, urea and HCO 3 , and a decrease in hematocrit and the levels of Cl and hemoglobin. No effects on blood physiology were observed in fish exposed to the lower concentrations of TNT (1-100μg/L). TNT and the metabolites 2-amino-4,6-dinitrotoluene (2-ADNT) and 4-amino-2,6-dinitrotoluene (4-ADNT) were found in the muscle tissue, whereas only 2-ADNT and 4-ADNT were found in the bile. The rapid excretion and estimated bioconcentration factors (range of 2-18 after 48h in gills, blood, liver, kidney, muscle and brain) indicated a low potential for bioaccumulation of TNT. Copyright © 2017 Elsevier B.V. All rights reserved.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    Duffy, T A; Iwanowicz, L R; McCormick, S D

    2014-07-01

    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 (4 day) exposures using three doses each of 17 α-ethinylestradiol (EE2), 17 β-estradiol (E2), and nonylphenol (NP) on four early life stages; embryos, yolk-sac larvae, feeding fry and 1 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 embryos. 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 plasma Vtg is a more sensitive indicator at this life stage. HSI was increased at the highest doses of EE2 and E2, and plasma T3 was decreased at the highest dose of EE2. Our results indicate that all life stages 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. Copyright © 2014 Elsevier B.V. All rights

  1. Early stress responses in Atlantic salmon (Salmo salar) exposed to environmentally relevant concentrations of uranium

    International Nuclear Information System (INIS)

    Song You; Salbu, Brit; Heier, Lene Sørlie; Teien, Hans-Christian; Lind, Ole-Christian; Oughton, Deborah; Petersen, Karina; Rosseland, Bjørn Olav; Skipperud, Lindis; Tollefsen, Knut Erik

    2012-01-01

    Uranium (U) is a naturally occurring heavy metal widely used in many military and civil applications. Uranium contamination and the associated potential adverse effects of U on the aquatic environment have been debated during recent years. In order to understand the effect and mode of action (MoA) of U in vivo, juvenile Atlantic salmon (Salmo salar) were exposed to 0.25 mg/L, 0.5 mg/L and 1.0 mg/L waterborne depleted uranyl acetate, respectively, in a static system for 48 h. The U concentrations in the gill and liver were analyzed by inductively coupled plasma mass spectrometry (ICP-MS) and the resulting biological effects were determined by a combination of analysis of gene expression and micronuclei formation. The hepatic transcriptional level of 12 biomarker genes from four stress–response categories, including oxidative stress (γ-glutamyl cysteine synthetase (GCS), glutathione reductase (GR), glutathione peroxidase (GPx)), DNA damage and repair (P53, cyclin-dependent kinase inhibitor 1 (P21), growth arrest and DNA damage-inducible gene gamma (Gadd45G), proliferating cell nuclear antigen (PCNA), Rad51), apoptosis (Bcl2-associated X protein (BAX), Bcl-x, Caspase 6A,) and protein degradation (Ubiquitin) were evaluated by quantitative real-time polymerase chain reaction (q-rtPCR). The results clearly showed accumulation of U in the gill and liver with increasing concentrations of U in the exposure water. The effects of U on differential hepatic gene expression also occurred in a concentration-dependent manner, although deviations from ideal concentration–response relationships were observed at the highest U concentration (1.0 mg/L). All the genes tested were found to be up-regulated by U while no significant micronuclei formation was identified. The results suggest that U may cause oxidative stress in fish liver at concentrations greater than 0.25 mg/L, giving rise to clear induction of several toxicologically relevant biomarker genes, although no significant

  2. Effects of dietary n-3 fatty acids on Toll-like receptor activation in primary leucocytes from Atlantic salmon (Salmo salar).

    Science.gov (United States)

    Arnemo, Marianne; Kavaliauskis, Arturas; Andresen, Adriana Magalhaes Santos; Bou, Marta; Berge, Gerd Marit; Ruyter, Bente; Gjøen, Tor

    2017-08-01

    The shortage of the n-3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) on the international markets has led to increasing substitution of fish oil by plant oils in Atlantic salmon (Salmo salar) feed and thereby reducing the EPA and DHA content in salmon. However, the minimum required levels of these fatty acids in fish diets for securing fish health are unknown. Fish were fed with 0, 1 or 2% EPA or DHA alone or in combination of both over a period, growing from 50 to 400 g. Primary head kidney leucocytes were isolated and stimulated with Toll-like receptor (TLR) ligands to determine if EPA and DHA deficiency can affect expression of important immune genes and eicosanoid production. Several genes related to viral immune response did not vary between groups. However, there was a tendency that the high-level EPA and DHA groups expressed lower levels of IL-1β in non-stimulated leucocytes. These leucocytes were also more responsive to the TLR ligands, inducing higher expression levels of IL-1β and Mx1 after stimulation. The levels of prostaglandin E2 and leukotriene B4 in serum and media from stimulated leucocytes were lower in both low and high EPA and DHA groups. In conclusion, leucocytes from low EPA and DHA groups seemed to be less responsive towards immunostimulants, like TLR ligands, indicating that low levels or absence of dietary EPA and DHA may have immunosuppressive effects.

  3. Antioxidant properties of salmon (Salmo salar L.) protein fraction hydrolysates revealed following their ex vivo digestion and in vitro hydrolysis.

    Science.gov (United States)

    Borawska, Justyna; Darewicz, Małgorzata; Pliszka, Monika; Vegarud, Gerd E

    2016-06-01

    Salmon (Salmo salar L.) myofibryllar protein (MP) and sarcoplasmic protein (SP) were digested with human gastric and duodenal juices and hydrolysed in vitro with commercial pepsin and Corolase PP. The digestion after duodenal juice/Corolase PP caused almost complete breakdown of peptide bonds in MP and SP. The DPPH(•) scavenging activity of proteins decreased during both ex vivo digestion and in vitro hydrolysis. The highest value of DPPH(•) scavenging activity was shown for the gastric digest of SP (8.88 ± 0.87%). The ABTS(+•) scavenging activity of MP and SP increased during digestion/hydrolysis. The duodenal digest of SP was characterised by the highest value of ABTS(+•) scavenging activity (72.7 ± 1.2%). In turn, the highest value of ferric-reducing power was determined for the gastric digest of SP (84.8 ± 0.2%). Salmon antioxidant peptides Phe-Ile-Lys-Lys, His-Leu, Ile-Tyr, Pro-His-Leu, Pro-Trp, Val-Pro-Trp were identified in both ex vivo digested and in vitro hydrolysed MP and SP. An antioxidant peptide, Val-Tyr, was additionally detected in the in vitro hydrolysate of SP. The results indicate the salmon myofibrillar and sarcoplasmic protein fractions as potential sources of antioxidant peptides that could be released in the gastrointestinal tract but their amino acid sequence and quantification vary. © 2015 Society of Chemical Industry. © 2015 Society of Chemical Industry.

  4. Local and systemic humoral immune response in farmed Atlantic salmon (Salmo salar L.) under a natural amoebic gill disease outbreak.

    Science.gov (United States)

    Marcos-López, Mar; Espinosa Ruiz, Cristóbal; Rodger, Hamish D; O'Connor, Ian; MacCarthy, Eugene; Esteban, M Ángeles

    2017-07-01

    Amoebic gill disease (AGD), caused by the protozoan parasite Neoparamoeba perurans, is one of the most significant infectious diseases for Atlantic salmon (Salmo salar L.) mariculture. The present study investigated the humoral immune response (both local in gill mucus and systemic in serum) of farmed Atlantic salmon naturally infected with N. perurans in commercial sea pens, at two different stages of the disease and after freshwater treatment. Parameters analysed included activity of immune related enzymes (i.e. lysozyme, peroxidase, protease, anti-protease, esterase, alkaline phosphatase), IgM levels, and the terminal carbohydrate profile in the gill mucus. Overall, greater variations between groups were noted in the immune parameters determined in gill mucus than the equivalent in the serum. In gill mucus, IgM levels and peroxidase, lysozyme, esterase and protease activities were decreased in fish showing longer exposure time to the infection and higher disease severity, then showed a sequential increase after treatment. Results obtained highlight the capacity of gills to elicit a local response to the infection, indicate an impaired immune response at the later stages of the disease, and show partial reestablishment of the host immune status after freshwater treatment. In addition to providing data on the humoral response to AGD, this study increases knowledge on gill mucosal humoral immunity, since some of the parameters were analysed for the first time in gill mucus. Copyright © 2017 Elsevier Ltd. All rights reserved.

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

    Science.gov (United States)

    Vindas, Marco A; Sørensen, Christina; Johansen, Ida B; Folkedal, Ole; Höglund, Erik; Khan, Uniza W; Stien, Lars H; Kristiansen, Tore S; Braastad, Bjarne O; Øverli, Øyvind

    2014-01-01

    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.

  6. Characterization of full-length sequenced cDNA inserts (FLIcs) from Atlantic salmon (Salmo salar)

    Science.gov (United States)

    Andreassen, Rune; Lunner, Sigbjørn; Høyheim, Bjørn

    2009-01-01

    DNA libraries generated by SGP represent a valuable cCDS FLIc source. The conservation of 7-mers in 3'UTRs indicates that these motifs are functionally important. Identity between some of these 7-mers and miRNA target sequences suggests that they are miRNA targets in Salmo salar transcripts as well. PMID:19878547

  7. Characterization of full-length sequenced cDNA inserts (FLIcs from Atlantic salmon (Salmo salar

    Directory of Open Access Journals (Sweden)

    Lunner Sigbjørn

    2009-10-01

    suggests that the remaining cDNA libraries generated by SGP represent a valuable cCDS FLIc source. The conservation of 7-mers in 3'UTRs indicates that these motifs are functionally important. Identity between some of these 7-mers and miRNA target sequences suggests that they are miRNA targets in Salmo salar transcripts as well.

  8. Speciation, uptake and toxicity of uranium in Atlantic Salmon (Salmo salar)

    Energy Technology Data Exchange (ETDEWEB)

    Teien, Hans-Christian; Hertel-Aas, Turid; Lind, Ole Christian; Skipperud, Lindis; Oughton, Deborah H.; Salbu, Brit [Norwegian University of Life Sciences (NMBU), Center of Excellence in Environmental Radioactivity (CERAD). P.O. Box 5003, N-1432 Aas (Norway); Thoerring, Haavard [Norwegian Radiation Protection Authority (NRPA), P.O. Box 55, N-1332 Oesteraas (Norway)

    2014-07-01

    To obtain information about the bioavailability of uranium (U) and its chemical toxicity, a significant number of Atlantic Salmon (Salmo salar) juveniles (in total about 800 fish) were exposure to commercial available depleted uranium (DU) in controlled experiments conducted in accordance with the OECD guidelines for acute toxicity tests. Speciation, gill accumulation and induced toxicity of U as a function of varying water concentrations of H{sup +}, Ca{sup 2+}, Mg{sup 2+}, Na{sup +} and K{sup +} as well as U were studied. In addition to recording mortality, blood samples were collected and analysed for general stress parameters (plasma Cl and glucose) prior to fish dissection and collection of different tissues. The observed dose-response demonstrated that varying concentrations of K{sup +}, Na{sup +} or Mg{sup 2+} had no apparent effect on the U induced toxicity in terms of 96 h LC50-values. U toxicity was, however, strongly dependent on pH. Reducing pH from about 6.7 to 6.0 or 5.5 reduced the LC50-value from 3.1 to 1.4 mg U/l. However, by increasing pH to 7.9, LC50-values increased to 25 mg/L. Fractionation of the exposure waters, demonstrated that U was present as dissolved species less than 10 kDa in size predominantly as anion, and that a fraction (30%) was present as U colloids ( 3-10 kDa). Furthermore, U accumulated in fish gills, and the accumulation of U in the fish gills increased with increasing U concentration in the water. U accumulation at >50 μg U/g dry weight gill was correlated with ion regulation problems and stress response in fish, reflected by reduced plasma Cl concentration and increased blood glucose, and mortality was observed at concentration levels >300 μg/g gill dry weight. Thus, toxic effects in fish were correlated to U concentration in gills, and the concentration of U in gills was highly dependent upon pH in water and the U speciation. As presented in detail on a poster at the present conference (Cagno et al.), U did not only

  9. Efecto de reducir la frecuencia de alimentación en la supervivencia, crecimiento, conversión y conducta alimenticia en juveniles de salmón del Atlántico Salmo salar (Linnaeus, 1758: experiencia a nivel productivo Effect of reducing the feeding frequency on the survival, growth, conversion, and feeding behavior of juvenile Atlantic salmon Salmo salar (Linnaeus, 1758: an experience at the productive level

    Directory of Open Access Journals (Sweden)

    Héctor Flores

    2012-09-01

    Full Text Available En Chile, la mayoría de las empresas de cultivo de salmones en la fase parr alimentan a los peces con 24 raciones/día; por otra parte, el alimento en el estómago de los peces, puede permanecer cerca de 4 a 5 h. Este trabajo evalúa en base a procedimientos y protocolos productivos, la disminución en la frecuencia de raciones de alimento y su efecto en la supervivencia, crecimiento, conversión y conducta de alimentación de los peces. Se trabajó en condiciones normales de producción comercial, con aproximadamente 1.200.000 peces de 0,17 g durante cuatro meses. Hubo dos tratamientos, el control con 24 raciones/día y el ensayo, que al inicio de la experiencia se entrego 12 raciones/día y al finalizar la experiencia se proporcionó 4 raciones/día. Se emplearon cinco estanques de 18 m³ para cada tratamiento. La disminución en la frecuencia de alimentación, no afectó la supervivencia de Salmo salar, se obtuvo mayor crecimiento en los peces del ensayo, con mejor conversión de alimento, se logró reducción de alimento depositado en el fondo de los estanques y se visualizó mejor apetito en los peces.In Chile, most salmon-farming companies feed fish in the parr phase 24 rations/day. However, food can remain in fish stomachs for around four or five hours. Using productive procedures and protocols, this study evaluates less frequent food rations and how they affect the survival, growth, conversion, and feeding behavior of the fish. The study was conducted over four months under normal commercial production conditions, using approximately 1,200,000 fish of 0.17 g each. There were two treatments: the control, which received 24 rations/day, and the assay, which received 12 rations/day at the onset of the study and 4 rations/day at the end of this. Five tanks, each 18 m³, were used for each treatment. The lower feeding frequency did not affect the survival of Salmo salar. The fish in the assay obtained greater growth and had better food

  10. Transcriptional changes in Atlantic salmon (Salmo salar) after embryonic exposure to road salt.

    Science.gov (United States)

    Tollefsen, Knut Erik; Song, You; Kleiven, Merethe; Mahrosh, Urma; Meland, Sondre; Rosseland, Bjørn Olav; Teien, Hans-Christian

    2015-12-01

    Road salt is extensively used as a deicing chemical in road maintenance during winter and has in certain areas of the world led to density stratifications in lakes and ponds, and adversely impacted aquatic organisms in the recipients of the road run-off. Aquatic vertebrates such as fish have been particularly sensitive during fertilisation, as the fertilisation of eggs involves rapid uptake of the surrounding water, reduction in egg swelling and in ovo exposure to high road salt concentrations. The present study aimed to identify the persistent molecular changes occurring in Atlantic salmon (Salmo salar) eggs after 24h exposure to high concentrations (5000 mg/L) of road salt at fertilisation. The global transcriptional changes were monitored by a 60k salmonid microarray at the eyed egg stage (cleavage stage, 255 degree days after fertilisation) and identified a high number of transcripts being differentially regulated. Functional enrichment, pathway and gene-gene interaction analysis identified that the differentially expressed genes (DEGs) were mainly associated with toxiciologically relevant processes involved in osmoregulation, ionregulation, oxidative stress, metabolism (energy turnover), renal function and developmental in the embryos. Quantitative rtPCR analysis of selected biomarkers, identified by global transcriptomics, were monitored in the eggs for an extended range of road salt concentrations (0, 50, 100, 500 and 5000 mg/L) and revealed a positive concentration-dependent increase in cypa14, a gene involved in lipid turnover and renal function, and nav1, a gene involved in neuraxonal development. Biomarkers for osmoregulatory responses such as atp1a2, the gene encoding the main sodium/potassium ATP-fueled transporter for chloride ions, and txdc9, a gene involved in regulation of cell redox homeostasis (oxidative stress), displayed apparent concentration-dependency with exposure, although large variance in the control group precluded robust statistical

  11. HPLC confirmatory method development for the determination of seven quinolones in salmon tissue (Salmo salar L.) validated according to the European Union Decision 2002/657/EC.

    Science.gov (United States)

    Evaggelopoulou, Evaggelia N; Samanidou, Victoria F

    2013-01-15

    A confirmatory high pressure liquid chromatographic method for the determination of seven quinolone antibiotics in tissue of Atlantic salmon (Salmo salar L.) was developed. Ciprofloxacin (CIP), danofloxacin (DAN), enrofloxacin (ENR), sarafloxacin (SAR), oxolinic acid (OXO), nalidixic acid (NAL) and flumequine (FLU) were separated on a Perfectsil ODS-2 120 (250 mm × 4 mm, 5 μm) column by gradient elution with a mobile phase consisting of 0.1% trifluoroacetic acid (pH=1), acetonitrile and methanol at 25°C within 22 min. Analytes were monitored at 255 nm (for the determination of OXO, NAL and FLU) and 275 nm (for CIP, DAN, ENR and SAR) by means of photodiode array detector. Examined quinolones were isolated from salmon tissue by extraction with citrate buffer solution (pH=4.7) and purified by solid phase extraction using Oasis HLB (200mg/6 mL) cartridges. The developed method was fully validated in terms of selectivity, linearity, accuracy, precision, stability and sensitivity according to the European Union Decision 2002/657/EC. The accuracy of the method was additionally proved by its application to certified reference material of salmon tissue (BCR® 725). Copyright © 2012 Elsevier Ltd. All rights reserved.

  12. Early life traits of farm and wild Atlantic salmon Salmo salar and first generation hybrids in the south coast of Newfoundland.

    Science.gov (United States)

    Hamoutene, D; Perez-Casanova, J; Burt, K; Lush, L; Caines, J; Collier, C; Hinks, R

    2017-06-01

    This study examined fertilization rates, survival and early life-trait differences of pure farm, wild and first generation (F1) hybrid origin embryos after crossing farm and wild Atlantic salmon Salmo salar. Results show that despite a trend towards higher in vitro fertilization success for wild females, differences in fertilization success in river water are not significantly different among crosses. In a hatchery environment, wild females' progeny (pure wild and hybrids with wild maternal parent) hatched 7-11 days earlier than pure farm crosses and hybrids with farm maternal parents. In addition, pure wild progeny had higher total lengths (L T ) at hatch than pure farm crosses and hybrids. Directions in trait differences need to be tested in a river environment, but results clearly show the maternal influence on early stages beyond egg-size differences. Differences in L T were no longer significant at 70 days post hatch (shortly after the onset of exogenous feeding) showing the need to investigate later developmental stages to better assess somatic growth disparities due to genetic differences. Higher mortality rates of the most likely hybrids (farm female × wild male hybrids) at egg and fry stages and their delayed hatch suggest that these F1 hybrids might be less likely to survive the early larval stages than wild stocks. © 2017 Her Majesty the Queen in Right of Canada. Journal of Fish Biology © 2017 The Fisheries Society of the British Isles.

  13. Establishment and characterization of a new cell line (SSP-9) derived from Atlantic salmon Salmo salar that expresses type I ifn.

    Science.gov (United States)

    Rodriguez Saint-Jean, S; González, C; Monrás, M; Romero, A; Ballesteros, N; Enríquez, R; Perez-Prieto, S

    2014-11-01

    In the present work, the establishment and biological characterization of a new cell line, SSP-9, derived from the pronephros of the Atlantic salmon Salmo salar, are reported. These cells grew well in Leibovitz's (L15) medium supplemented with 10% foetal calf serum at temperatures from 15 to 25° C, and they have been sub-cultured over 100 passages to produce a continuous cell line with an epithelial-like morphology. The SSP-9 cells attached and spread efficiently at different plating densities, retaining 80% of cell viability after storage in liquid nitrogen. When karyotyped, the cells had 40-52 chromosomes, with a modal number of 48. Viral susceptibility tests showed that SSP-9 cells were susceptible to infectious pancreatic necrosis virus and infectious haematopoietic necrosis virus, producing infectious virus and regular cytopathic effects. Moreover, these cells could be stimulated by poly I:C, showing significant up-regulation in the expression of the genes that regulate immune responses, such as ifn and mx-1. SSP-9 cells constitutively express genes characteristic of macrophages, such as major histocompatibility complex (mhc-II) and interleukin 12b (il-12b), and flow cytometry assays confirmed that SSP-9 cells can be permanently transfected with plasmids expressing a reporter gene. Accordingly, this new cell line is apparently suitable for transgenic manipulation, and to study host cell-virus interactions and immune processes. © 2014 The Fisheries Society of the British Isles.

  14. Application of heteroduplex analysis for detecting variation within the growth hormone 2 gene in Salmo trutta L. (brown trout).

    Science.gov (United States)

    Gross, R; Nilsson, J

    1995-03-01

    A new method to detect variation at a single copy nuclear gene in brown trout, Salmo trutta L., is provided. The technique entails (i) selective gene amplification by the polymerase chain reaction (PCR), (ii) digestion of amplification products by restriction endonucleases to obtain fragments of suitable size, (iii) hybridization with heterologous DNA followed by denaturation and reannealing to obtain heteroduplex molecules, and (iv) screening for variation in polyacrylamide gels. Variation was studied within a growth hormone 2 gene 1489 bp segment and polymorphism was detected in two HinfI-digested fragments. Formation of different heteroduplex patterns in experimental mixtures of digested amplification products from brown trout and Atlantic salmon, Salmo salar L., allowed us to determine the genotype of the brown trout. Polymorphism was observed in four out of six studied populations.

  15. The notochord in Atlantic salmon (Salmo salar L.) undergoes profound morphological and mechanical changes during development.

    Science.gov (United States)

    Kryvi, Harald; Rusten, Iselin; Fjelldal, Per Gunnar; Nordvik, Kari; Totland, Geir K; Karlsen, Tine; Wiig, Helge; Long, John H

    2017-11-01

    We present the development of the notochord of the Atlantic salmon (Salmo salar L.), from early embryo to sexually mature fish. Over the salmon's lifespan, profound morphological changes occur. Cells and gross structures of the notochord reorganize twice. In the embryo, the volume of the notochord is dominated by large, vacuolated chordocytes; each cell can be modeled as a hydrostat organized into a larger cellular-hydrostat network, structurally bound together with desmosomes. After the embryo hatches and grows into a fry, vacuolated chordocytes disappear, replaced by extracellular lacunae. The formation of mineralized, segmental chordacentra stiffens the notochord and creates intervertebral joints, where tissue strain during lateral bending is now focused. As development proceeds towards the parr stage, a process of devacuolization and intracellular filament accumulation occur, forming highly dense, non-vacuolated chordocytes. As extracellular lacunae enlarge, they are enclosed by dense filamentous chordocytes that form transverse intervertebral septa, which are connected to the intervertebral ligaments, and a longitudinal notochordal strand. In the vertebral column of pelagic adults, large vacuolated chordocytes reappear; cells of this secondary population have a volume up to 19 000 times larger than the primary vacuolated chordocytes of the early notochord. In adults the lacunae have diminished in relative size. Hydrostatic pressure within the notochord increases significantly during growth, from 525 Pa in the alevins to 11 500 Pa in adults, at a rate of increase with total body length greater than that expected by static stress similarity. Pressure and morphometric measurements were combined to estimate the stress in the extracellular material of the notochordal sheath and intervertebral ligaments and the flexural stiffness of the axial skeleton. The functional significance of the morphological changes in the axial skeleton is discussed in relation to the

  16. Tissue distribution and elimination of deoxynivalenol and ochratoxin A in dietary-exposed Atlantic salmon (Salmo salar).

    Science.gov (United States)

    Bernhoft, Aksel; Høgåsen, Helga R; Rosenlund, Grethe; Ivanova, Lada; Berntssen, Marc H G; Alexander, Jan; Eriksen, Gunnar Sundstøl; Fæste, Christiane Kruse

    2017-07-01

    Post-smolt Atlantic salmon (Salmo salar) were fed standard feed with added 2 or 6 mg kg -1 pure deoxynivalenol (DON), 0.8 or 2.4 mg kg -1 pure ochratoxin A (OTA), or no added toxins for up to 8 weeks. The experiments were performed in duplicate tanks with 25 fish each per diet group, and the feed was given for three 2-h periods per day. After 3, 6 and 8 weeks, 10 fish from each diet group were sampled. In the following hours after the last feeding at 8 weeks, toxin elimination was studied by sampling three fish per diet group at five time points. Analysis of DON and OTA in fish tissues and plasma was conducted by liquid chromatography-mass spectrometry and high-pressure liquid chromatography with fluorescence detection, respectively. DON was distributed to the liver, kidney, plasma, muscle, skin and brain, and the concentrations in liver and muscle increased significantly from 3 to 8 weeks of exposure to the high-DON diet. After the last feeding at 8 weeks, DON concentration in liver reached a maximum at 1 h and decreased thereafter with a half-life (t 1/2 ) of 6.2 h. DON concentration in muscle reached a maximum at 6 h and was then eliminated with a t 1/2  = 16.5 h. OTA was mainly found in liver and kidney, and the concentration in liver decreased significantly from 3 to 8 weeks in the high-OTA group. OTA was eliminated faster than DON from various tissues. By using Norwegian food consumption data and kinetic findings in this study, we predicted the human exposure to DON and OTA from fish products through carryover from the feed. Following a comparison with tolerable daily intakes, we found the risk to human health from the consumption of salmon-fed diets containing maximum recommended levels of these toxins to be negligible.

  17. Hanhaqimei,a Salar Woman

    Institute of Scientific and Technical Information of China (English)

    1997-01-01

    The Salar nationality,with apopulation of 87,697,mainly settles in Xunhua Salar Nationality Autonomous County in eastern Qinghai Province.The Salar have their own spoken language,but no written script.Most of the Salar use Mandarin Chinese.According to legend and historians,their ancestors movde to Xunhua from Middle Asia in the 13th century.The Salar living by the Yellow River engage in agriculture and animal husbandry as their Primary means of support. The Salar believe in Islam and are also greatly influenced by confucian culture developed by the Han nationality.

  18. Effects of algal-produced neurotoxins on metabolic activity in telencephalon, optic tectum and cerebellum of Atlantic salmon (Salmo salar)

    International Nuclear Information System (INIS)

    Bakke, Marit Jorgensen; Horsberg, Tor Einar

    2007-01-01

    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 μg STX/kg bw), BTX (68 μg BTX/kg bw) or DA (6 mg DA/kg bw). In addition, 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

  19. 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.

  20. 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.

  1. Accuracy of Assignment of Atlantic Salmon (Salmo salar L.) to Rivers and Regions in Scotland and Northeast England Based on Single Nucleotide Polymorphism (SNP) Markers

    Science.gov (United States)

    Gilbey, John; Cauwelier, Eef; Coulson, Mark W.; Stradmeyer, Lee; Sampayo, James N.; Armstrong, Anja; Verspoor, Eric; Corrigan, Laura; Shelley, Jonathan; Middlemas, Stuart

    2016-01-01

    Understanding the habitat use patterns of migratory fish, such as Atlantic salmon (Salmo salar L.), and the natural and anthropogenic impacts on them, is aided by the ability to identify individuals to their stock of origin. Presented here are the results of an analysis of informative single nucleotide polymorphic (SNP) markers for detecting genetic structuring in Atlantic salmon in Scotland and NE England and their ability to allow accurate genetic stock identification. 3,787 fish from 147 sites covering 27 rivers were screened at 5,568 SNP markers. In order to identify a cost-effective subset of SNPs, they were ranked according to their ability to differentiate between fish from different rivers. A panel of 288 SNPs was used to examine both individual assignments and mixed stock fisheries and eighteen assignment units were defined. The results improved greatly on previously available methods and, for the first time, fish caught in the marine environment can be confidently assigned to geographically coherent units within Scotland and NE England, including individual rivers. As such, this SNP panel has the potential to aid understanding of the various influences acting upon Atlantic salmon on their marine migrations, be they natural environmental variations and/or anthropogenic impacts, such as mixed stock fisheries and interactions with marine power generation installations. PMID:27723810

  2. Immunomodulatory Effects of Dietary Seaweeds in LPS Challenged Atlantic Salmon Salmo salar as Determined by Deep RNA Sequencing of the Head Kidney Transcriptome

    Science.gov (United States)

    Palstra, Arjan P.; Kals, Jeroen; Blanco Garcia, Ainhoa; Dirks, Ron P.; Poelman, Marnix

    2018-01-01

    Seaweeds may represent immuno-stimulants that could be used as health-promoting fish feed components. This study was performed to gain insights into the immunomodulatory effects of dietary seaweeds in Atlantic salmon. Specifically tested were 10% inclusion levels of Laminaria digitata (SW1) and a commercial blend of seaweeds (Oceanfeed®) (SW2) against a fishmeal based control diet (FMC). Differences between groups were assessed in growth, feed conversion ratio and blood parameters hematocrit and hemoglobin. After a LPS challenge of fish representing each of the three groups, RNAseq was performed on the head kidney as major immune organ to determine transcriptomic differences in response to the immune activation. Atlantic salmon fed with dietary seaweeds did not show major differences in performance in comparison with fishmeal fed fish. RNAseq resulted in ∼154 million reads which were mapped against a NCBI Salmo salar reference and against a de novo assembled S. salar reference for analyses of expression of immune genes and ontology of immune processes among the 87,600 cDNA contigs. The dietary seaweeds provoked a more efficient immune response which involved more efficient identification of the infection site, and processing and presentation of antigens. More specifically, chemotaxis and the chemokine-mediated signaling were improved and therewith the defense response to Gram-positive bacterium reduced. Specific Laminaria digitata effects included reduction of the interferon-gamma-mediated signaling. Highly upregulated and specific for this diet was the expression of major histocompatibility complex class I-related gene protein. The commercial blend of seaweeds caused more differential expression than Laminaria digitata and improved immune processes such as receptor-mediated endocytosis and cell adhesion, and increased the expression of genes involved in response to lipopolysaccharide and inflammatory response. Particularly, expression of many important immune

  3. Carbon monoxide stunning of Atlantic salmon (Salmo salar L.) modifies rigor mortis and sensory traits as revealed by NIRS and other instruments.

    Science.gov (United States)

    Concollato, Anna; Parisi, Giuliana; Masoero, Giorgio; Romvàri, Robert; Olsen, Rolf-Erik; Dalle Zotte, Antonella

    2016-08-01

    Methods of stunning used in salmon slaughter are still the subject of research. Fish quality can be influenced by pre-, ante- and post-mortem conditions, including handling before slaughter, slaughter methods and storage conditions. Carbon monoxide (CO) is known to improve colour stability in red muscle and to reduce microbial growth and lipid oxidation in live fish exposed to CO. Quality differences in Atlantic salmon, Salmo salar L., stunned by CO or percussion, were evaluated and compared by different techniques [near infrared reflectance spectroscopy (NIRS), electronic nose (EN), electronic tongue (ET)] and sensory analysis. Thawed samples, freeze-dried preparates and NIRS devices proved to be the most efficient combinations for discriminating the treatments applied to salmon, i.e. first the stunning methods adopted, then the back-prediction of the maximum time to reach rigor mortis and finally to correlate some sensory attributes. A trained panel found significant differences between control and CO-stunned salmon: reduced tactile crumbliness, reduced odour and aroma intensities, and reduced tenderness of CO-treated fillets. CO stunning reduced radiation absorbance in spectra of thawed and freeze-dried fillets, but not fillet samples stored in ethanol, where it may have interacted with myoglobin and myosin. The good results in a rapid discrimination of thawed samples detected by NIRS suggest suitable applications in the fish industry. CO treatment could mitigate sensory perception, but consumer tests are needed to confirm our findings. © 2015 Society of Chemical Industry. © 2015 Society of Chemical Industry.

  4. A comparative study of diploid versus triploid Atlantic salmon (Salmo salar L.). The effects of rearing temperatures (5, 10 and 15°C) on raw material characteristics and storage quality.

    Science.gov (United States)

    Lerfall, Jørgen; Hasli, Pål Rune; Skare, Even Flønes; Olsen, Rolf Erik; Rotabakk, Bjørn Tore; Roth, Bjørn; Slinde, Erik; Egelandsdal, Bjørg

    2017-06-15

    Several major market operators argue that the current level of knowledge about quality is too scant to justify a switch to a large-scale production of triploid salmon. The aim of the present study was, therefore, to elucidate how rearing conditions (5, 10 and 15°C) affect the flesh quality of triploid Atlantic salmon (Salmo salar L., 1.6±0.3kg). As a reference, diploid salmon kept under equal conditions and with equal genetics were used. The main design discriminant was the holding temperature; increased temperature gave increased blood lactate, rigor index (I r ), drip loss (DL), content of astaxanthin and intensity of redness, but reduced muscle pH, cathepsin activity and fillet lightness. Salmon kept at 10°C grew the fastest. It is concluded that ploidy gave less variation than temperature. Triploids were characterized by lower blood haematocrit (Hct) and I r , higher DL and collagenase activity, and on average, paler and less yellowish fillets. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Immunostimulation of Salmo salar L., and its effect on Lepeophtheirus salmonis (Krøyer) P-glycoprotein mRNA expression following subsequent emamectin benzoate exposure.

    Science.gov (United States)

    Igboeli, O O; Purcell, S L; Wotton, H; Poley, J; Burka, J F; Fast, M D

    2013-03-01

    Control of sea lice, Lepeophtheirus salmonis, on farmed Atlantic salmon, Salmo salar, relies heavily on chemotherapeutants. However, reduced efficacy of many treatments and need for integrated sea lice management plans require innovative strategies. Resistance to emamectin benzoate (EMB), a major sea lice parasiticide, has been linked with P-glycoprotein (P-gp) expression. We hypothesized that host immunostimulation would complement EMB treatment outcome. Lepeophtheirus salmonis-infected Atlantic salmon were fed immunostimulatory or control feeds. Sea lice were collected for 24-h EMB bioassays 1 and 2 weeks prior to commencement of EMB treatment of the fish. Two weeks after cessation of immunostimulant-treated feed, EMB was administered at 150 μg kg(-1) fish biomass for 7 days. The bioassay revealed stage, gender and immunostimulant-related differences in EMB EC(50) . Sea lice attached to salmon with a history of immunostimulation exhibited significantly greater survival than those on control feeds, despite similar levels of EMB in host tissues. Lepeophtheirus salmonis from salmon with a history of immunostimulation also exhibited higher P-gp mRNA expression as well as greater survivability compared to controls. Administration of immunostimulants prior to EMB treatment caused increased expression of P-gp mRNA which could have consequently caused decreased efficacy of the parasiticide. © 2013 Blackwell Publishing Ltd.

  6. Biopsie et mesure de l'activité Na+/K+ ATPasique branchiale : validité et impact sur le développement du smolt de saumon Atlantique (Salmo salar L.

    Directory of Open Access Journals (Sweden)

    SIEGLER L.

    1996-01-01

    Full Text Available Une biopsie de fragment de tissu branchial a été effectuée, durant toute la période de smoltification, sur des juvéniles de saumons Atlantique (Salmo salar élevés en pisciculture. Le microdosage de l'activité de la Na+/K+ ATPase branchiale, effectué sur ce fragment de tissu, a été comparé au macrodosage obtenu à partir des branchies entières. Aucune mortalité n'a été observée chez les saumons biopsies dont le taux de croissance (linéaire et pondérale est resté identique à celui des poissons témoins. La bonne correspondance des cinétiques de l'activité enzymatique obtenues par les deux méthodes valide la technique de microdosage et confirme l'absence d'influence sur le développement physiologique ultérieur du smolt biopsie. Nos résultats montrent les modifications envisageables pour améliorer la sensibilité de la méthode. Cette technique est très prometteuse pour l'analyse des populations naturelles

  7. Sensitivity and toxic mode of action of dietary organic and inorganic selenium in Atlantic salmon (Salmo salar).

    Science.gov (United States)

    Berntssen, M H G; Sundal, T K; Olsvik, P A; Amlund, H; Rasinger, J D; Sele, V; Hamre, K; Hillestad, M; Buttle, L; Ørnsrud, R

    2017-11-01

    Depending on its chemical form, selenium (Se) is a trace element with a narrow range between requirement and toxicity for most vertebrates. Traditional endpoints of Se toxicity include reduced growth, feed intake, and oxidative stress, while more recent finding describe disturbance in fatty acid synthesis as underlying toxic mechanism. To investigate overall metabolic mode of toxic action, with emphasis on lipid metabolism, a wide scope metabolomics pathway profiling was performed on Atlantic salmon (Salmo salar) (572±7g) that were fed organic and inorganic Se fortified diets. Atlantic salmon were fed a low natural background organic Se diet (0.35mg Se kg -1 , wet weight (WW)) fortified with inorganic sodium selenite or organic selenomethionine-yeast (SeMet-yeast) at two levels (∼1-2 or 15mgkg -1 , WW), in triplicate for 3 months. Apparent adverse effects were assessed by growth, feed intake, oxidative stress as production of thiobarbituric acid-reactive substances (TBARS) and levels of tocopherols, as well as an overall metabolomic pathway assessment. Fish fed 15mgkg -1 selenite, but not 15mgkg -1 SeMet-yeast, showed reduced feed intake, reduced growth, increased liver TBARS and reduced liver tocopherol. Main metabolic pathways significantly affected by 15mgkg -1 selenite, and to a lesser extent 15mgkg -1 SeMet-yeast, were lipid catabolism, endocannabinoids synthesis, and oxidant/glutathione metabolism. Disturbance in lipid metabolism was reflected by depressed levels of free fatty acids, monoacylglycerols and diacylglycerols as well as endocannabinoids. Specific for selenite was the significant reduction of metabolites in the S-Adenosylmethionine (SAM) pathway, indicating a use of methyl donors that could be allied with excess Se excretion. Dietary Se levels to respectively 1.1 and 2.1mgkg -1 selenite and SeMet-yeast did not affect any of the above mentioned parameters. Apparent toxic mechanisms at higher Se levels (15mgkg -1 ) included oxidative stress and

  8. Commercial trials using emamectin benzoate to control sea lice Lepeophtheirus salmonis infestations in Atlantic salmon Salmo salar.

    Science.gov (United States)

    Stone, J; Sutherland, I H; Sommerville, C; Richards, R H; Varma, K J

    2000-06-19

    Two trials were conducted at commercial salmon farms to evaluate the efficacy of emamectin benzoate (Slice, 0.2% aquaculture pre-mix, Schering-Plough Animal Health) as a treatment for sea lice Lepeophtheirus salmonis (Krøyer) and Caligus elongatus Nordmann infestations in Atlantic salmon Salmo salar L. Trials were carried out in 15 m2 commercial sea pens, at temperatures of 5.5 to 7.5 degrees C and 10.8 to 13.8 degrees C. Each pen was stocked with 14,000 to 17,500 fish with mean weights of 0.44 to 0.74 and 1.33 to 1.83 kg. Fish were naturally infested with sea lice at the start of each trial. At Day -1, samples of 10 or 15 fish were taken from each pen to determine pre-treatment numbers of lice. Emamectin benzoate was administered in feed, to 4 replicate pens, at a dose of 50 micrograms kg-1 biomass d-1 for 7 consecutive days (Days 0 to 6). Sea lice were counted again, between Days 7 and 77, and comparisons made with untreated control fish. Despite adverse weather conditions, wide variations in fish weights and exposure to new infestations, treatment was effective against chalimus and motile stages of L. salmonis. In the autumn trial, efficacy at Day 27 was 89%, and lice numbers remained lower on treated fish than on control fish 64 d from the start of treatment. In the winter trial, reductions in lice numbers at low temperatures were slower but good efficacy was achieved by Day 35. Although control fish had to be treated with hydrogen peroxide at Day 21, fish treated only with emamectin benzoate on Days 0 to 6 still had 89% fewer lice than control fish at Day 35. There were very few C. elongatus present, but at the end of both trials numbers were lower on treated fish. No adverse effects were associated with treatment of fish with emamectin benzoate.

  9. Comparative analysis of innate immune responses to Streptococcus phocae strains in Atlantic salmon (Salmo salar) and rainbow trout (Oncorhynchus mykiss).

    Science.gov (United States)

    Salazar, Soraya; Oliver, Cristian; Yáñez, Alejandro J; Avendaño-Herrera, Ruben

    2016-04-01

    Streptococcus phocae subsp. salmonis is a Gram-positive bacterium that causes mortality only in Atlantic salmon (Salmo salar) farmed in Chile, even when this species is co-cultured with rainbow trout (Oncorhynchus mykiss). This susceptibility could be determined by innate immune response components and their responses to bacterial infection. This fish pathogen shares subspecies status with Streptococcus phocae subsp. phocae isolated from seals. The present study compared innate immune system mechanisms in Atlantic salmon and rainbow trout when challenged with different S. phocae, including two isolates from Atlantic salmon (LM-08-Sp and LM-13-Sp) and two from seal (ATCC 51973(T) and P23). Streptococcus phocae growth was evaluated in the mucus and serum of both species, with rainbow trout samples evidencing inhibitory effects. Lysozyme activity supported this observation, with significantly higher (p trout serum and mucus as compared to Atlantic salmon. No differences were found in phagocytic capacity between fish species when stimulated with ATCC 51973(T) and P23. Against all S. phocae strains, rainbow trout and Atlantic salmon showed up to two-fold increased bactericidal activity, and rainbow trout demonstrated up to three-fold greater reactive oxygen species production in macrophages. In conclusion, the non-specific humoral and cellular barriers of Atlantic salmon were immunologically insufficient against S. phocae subsp. salmonis, thereby facilitating streptococcosis. Moreover, the more robust response of rainbow trout to S. phocae could not be attributed to any specific component of the innate immune system, but was rather the consequence of a combined response by the evaluated components. Copyright © 2016 Elsevier Ltd. All rights reserved.

  10. Experimental Transmission of Infectious Pancreatic Necrosis Virus from the Blue Mussel, Mytilus edulis, to Cohabitating Atlantic Salmon (Salmo salar) Smolts

    Science.gov (United States)

    Pietrak, Michael R.; Bricknell, Ian

    2013-01-01

    Integrated multitrophic aquaculture (IMTA) reduces the environmental impacts of commercial aquaculture systems by combining the cultivation of fed species with extractive species. Shellfish play a critical role in IMTA systems by filter-feeding particulate-bound organic nutrients. As bioaccumulating organisms, shellfish may also increase disease risk on farms by serving as reservoirs for important finfish pathogens such as infectious pancreatic necrosis virus (IPNV). The ability of the blue mussel (Mytilus edulis) to bioaccumulate and transmit IPNV to naive Atlantic salmon (Salmo salar) smolts was investigated. To determine the ability of mussels to filter and accumulate viable IPNV, mussels were held in water containing log 4.6 50% tissue culture infective dose(s) (TCID50) of the West Buxton strain of IPNV ml−1. Viable IPNV was detected in the digestive glands (DGs) of IPNV-exposed mussels as early as 2 h postexposure. The viral load in mussel DG tissue significantly increased with time and reached log 5.35 ± 0.25 TCID50 g of DG tissue−1 after 120 h of exposure. IPNV titers never reached levels that were significantly greater than that in the water. Viable IPNV was detected in mussel feces out to 7 days postdepuration, and the virus persisted in DG tissues for at least 18 days of depuration. To determine whether IPNV can be transmitted from mussels to Atlantic salmon, IPNV-exposed mussels were cohabitated with naive Atlantic salmon smolts. Transmission of IPNV did occur from mussels to smolts at a low frequency. The results demonstrate that a nonenveloped virus, such as IPNV, can accumulate in mussels and be transferred to naive fish. PMID:23872575

  11. Some quantitative indicators of postovulatory aging and its effect on larval and juvenile development of Atlantic salmon (Salmo salar).

    Science.gov (United States)

    Mommens, Maren; Storset, Arne; Babiak, Igor

    2015-07-01

    Modern out-of-season egg production in Atlantic salmon (Salmo salar) increases the risk of postovulatory aging (POA) of oocytes. Postovulatory aging is known to influence oocyte quality in salmonids, but reliable tests for POA are lacking in Atlantic salmon egg production. To address this problem, we have collected oocytes from the same 20 Atlantic salmon females sequentially in approximately 1-week intervals, from the start of ovulation until 28 days postovulation (dpo), to determine the effect of natural retention of matured oocytes in body coelomic cavity on further performance of embryos and juveniles produced from those oocytes. Also, we investigated oocyte water hardening and several coelomic fluid parameters as potential quantitative indicators of POA. Oocyte quality decreased significantly from 22 dpo onward, as inferred from decrease in fertilization success and survival of embryos, alevins, and juveniles and increase in alevin and juvenile deformity rates. The occurrence of head deformities was significantly related to postovulatory age of oocytes. Coelomic fluid pH decreased significantly at 28 dpo and correlated positively with fertilization rates (r = 0.45), normal eyed embryo rates (r = 0.67), and alevin relative survival rates (r = 0.63) and negatively correlated with total alevin deformity rates (r = -0.59). Oocyte weight gain at 60 minutes decreased significantly at 28 dpo and correlated negatively with total alevin deformities and the occurrence of cranial nodules (r = -0.99). Generally, quality of ovulated oocytes remained stable for the first 2 weeks after ovulation. Later on, POA negatively influenced Atlantic salmon embryo, alevin, and juvenile performance. For the first time, we show a long-term effect of POA on salmonid juvenile performance. Standardized pH measurements of coelomic fluid could potentially improve embryo and juvenile production by identifying low-quality oocytes at an early stage during the production. Copyright © 2015

  12. Tissue sterol composition in Atlantic salmon (Salmo salar L.) depends on the dietary cholesterol content and on the dietary phytosterol:cholesterol ratio, but not on the dietary phytosterol content.

    Science.gov (United States)

    Sissener, Nini H; Rosenlund, Grethe; Stubhaug, Ingunn; Liland, Nina S

    2018-03-01

    The aim of the study was to investigate how the dietary sterol composition, including cholesterol, phytosterol:cholesterol ratio and phytosterols, affect the absorption, biliary excretion, retention, tissue storage and distribution of cholesterol and individual phytosterols in Atlantic salmon (Salmo salar L.). A feeding trial was conducted at two different temperatures (6 and 12°C), using nine different diets with varying contents of phytosterols, cholesterol and phytosterol:cholesterol ratio. Cholesterol retention values were clearly dependent on dietary cholesterol, and showed that fish fed cholesterol levels phytosterol:cholesterol ratio, but not on the dietary phytosterol content in itself. Campesterol and brassicasterol appeared to be the phytosterols with the highest intestinal absorption in Atlantic salmon. There was a high biliary excretion of campesterol, but not of brassicasterol, which accumulated in tissues and particularly in adipose tissue, with 2-fold-higher retention at 12°C compared with 6°C. Campesterol had the second highest retention of the phytosterols in the fish, but with no difference between the two temperatures. Other phytosterols had very low retention. Although brassicasterol retention decreased with increasing dietary phytosterols, campesterol retention decreased with increasing dietary cholesterol, indicating differences in the uptake mechanisms for these two sterols.

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

    Directory of Open Access Journals (Sweden)

    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

  14. 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.

  15. 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.

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

    Science.gov (United States)

    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 ( n MSW  = 205 vs. n 1SW  = 30; p 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.

  17. 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.

  18. A dense SNP-based linkage map for Atlantic salmon (Salmo salar reveals extended chromosome homeologies and striking differences in sex-specific recombination patterns

    Directory of Open Access Journals (Sweden)

    Lien Sigbjørn

    2011-12-01

    Full Text Available Abstract Background The Atlantic salmon genome is in the process of returning to a diploid state after undergoing a whole genome duplication (WGD event between 25 and100 million years ago. Existing data on the proportion of paralogous sequence variants (PSVs, multisite variants (MSVs and other types of complex sequence variation suggest that the rediplodization phase is far from over. The aims of this study were to construct a high density linkage map for Atlantic salmon, to characterize the extent of rediploidization and to improve our understanding of genetic differences between sexes in this species. Results A linkage map for Atlantic salmon comprising 29 chromosomes and 5650 single nucleotide polymorphisms (SNPs was constructed using genotyping data from 3297 fish belonging to 143 families. Of these, 2696 SNPs were generated from ESTs or other gene associated sequences. Homeologous chromosomal regions were identified through the mapping of duplicated SNPs and through the investigation of syntenic relationships between Atlantic salmon and the reference genome sequence of the threespine stickleback (Gasterosteus aculeatus. The sex-specific linkage maps spanned a total of 2402.3 cM in females and 1746.2 cM in males, highlighting a difference in sex specific recombination rate (1.38:1 which is much lower than previously reported in Atlantic salmon. The sexes, however, displayed striking differences in the distribution of recombination sites within linkage groups, with males showing recombination strongly localized to telomeres. Conclusion The map presented here represents a valuable resource for addressing important questions of interest to evolution (the process of re-diploidization, aquaculture and salmonid life history biology and not least as a resource to aid the assembly of the forthcoming Atlantic salmon reference genome sequence.

  19. The mating brain: early maturing sneaker males maintain investment into the brain also under fast body growth in Atlantic salmon (Salmo salar).

    Science.gov (United States)

    Kotrschal, Alexander; Trombley, Susanne; Rogell, Björn; Brannström, Ioana; Foconi, Eric; Schmitz, Monika; Kolm, Niclas

    It has been suggested that mating behaviours require high levels of cognitive ability. However, since investment into mating and the brain both are costly features, their relationship is likely characterized by energetic trade-offs. Empirical data on the subject remains equivocal. We investigated if early sexual maturation was associated with brain development in Atlantic salmon ( Salmo salar ), in which males can either stay in the river and sexually mature at a small size (sneaker males) or migrate to the sea and delay sexual maturation until they have grown much larger (anadromous males). Specifically, we tested how sexual maturation may induce plastic changes in brain development by rearing juveniles on either natural or ad libitum feeding levels. After their first season we compared brain size and brain region volumes across both types of male mating tactics and females. Body growth increased greatly across both male mating tactics and females during ad libitum feeding as compared to natural feeding levels. However, despite similar relative increases in body size, early maturing sneaker males maintained larger relative brain size during ad libitum feeding levels as compared to anadromous males and females. We also detected several differences in the relative size of separate brain regions across feeding treatments, sexes and mating strategies. For instance, the relative size of the cognitive centre of the brain, the telencephalon, was largest in sneaker males. Our data support that a large relative brain size is maintained in individuals that start reproduction early also during fast body growth. We propose that the cognitive demands during complex mating behaviours maintain a high level of investment into brain development in reproducing individuals.

  20. Collagen type XI alpha1 may be involved in the structural plasticity of the vertebral column in Atlantic salmon (Salmo salar L.).

    Science.gov (United States)

    Wargelius, A; Fjelldal, P G; Nordgarden, U; Grini, A; Krossøy, C; Grotmol, S; Totland, G K; Hansen, T

    2010-04-01

    Atlantic salmon (Salmo salar L.) vertebral bone displays plasticity in structure, osteoid secretion and mineralization in response to photoperiod. Other properties of the vertebral bone, such as mineral content and mechanical strength, are also associated with common malformations in farmed Atlantic salmon. The biological mechanisms that underlie these changes in bone physiology are unknown, and in order to elucidate which factors might be involved in this process, microarray assays were performed on vertebral bone of Atlantic salmon reared under natural or continuous light. Eight genes were upregulated in response to continuous light treatment, whereas only one of them was upregulated in a duplicate experiment. The transcriptionally regulated gene was predicted to code for collagen type XI alpha1, a protein known to be involved in controlling the diameter of fibrillar collagens in mammals. Furthermore, the gene was highly expressed in the vertebrae, where spatial expression was found in trabecular and compact bone osteoblasts and in the chordoblasts of the notochordal sheath. When we measured the expression level of the gene in the tissue compartments of the vertebrae, the collagen turned out to be 150 and 25 times more highly expressed in the notochord and compact bone respectively, relative to the expression in the trabecular bone. Gene expression was induced in response to continuous light, and reduced in compressed vertebrae. The downregulation in compressed vertebrae was due to reduced expression in the compact bone, while expression in the trabecular bone and the notochord was unaffected. These data support the hypothesis that this gene codes for a presumptive collagen type XI alpha1, which may be involved in the regulatory pathway leading to structural adaptation of the vertebral architecture.

  1. 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.

  2. 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.

  3. 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.

  4. An analysis of genetic stock identification on a small geographical scale using microsatellite markers, and its application in the management of a mixed-stock fishery for Atlantic salmon Salmo salar in Ireland.

    Science.gov (United States)

    Ensing, D; Crozier, W W; Boylan, P; O'Maoiléidigh, N; McGinnity, P

    2013-06-01

    A genetic stock identification (GSI) study was undertaken in a fishery for Atlantic salmon Salmo salar to determine the effects of restrictive fishery management measures on the stock composition of the fishery, and if accurate and precise stock composition estimates could be achieved on the small geographical scale where this fishery operates, using a suite of only seven microsatellite loci. The stock composition of the Foyle fishery was shown to comprise almost exclusively of Foyle origin fish in the 3 years after restrictive measures were introduced in 2007, compared to 85% the year before. This showed that the restrictive measures resulted in the Foyle fishery being transformed from a mixed-stock fishery to an almost exclusively single-stock fishery, and showed how GSI studies can guide and evaluate management decisions to successfully manage these fisheries. Highly accurate and precise stock composition estimates were achieved in this study, using both cBAYES and ONCOR genetic software packages. This suggests accurate and precise stock composition is possible even on small geographical scales. © 2013 AFBINI. Journal of Fish Biology © 2013 The Fisheries Society of the British Isles.

  5. Low levels of very-long-chain n-3 PUFA in Atlantic salmon (Salmo salar) diet reduce fish robustness under challenging conditions in sea cages.

    Science.gov (United States)

    Bou, Marta; Berge, Gerd M; Baeverfjord, Grete; Sigholt, Trygve; Østbye, Tone-Kari; Ruyter, Bente

    2017-01-01

    The present study aimed to determine the minimum requirements of the essential n -3 fatty acids EPA and DHA in Atlantic salmon ( Salmo salar ) that can secure their health under challenging conditions in sea cages. Individually tagged Atlantic salmon were fed 2, 10 and 17 g/kg of EPA + DHA from 400 g until slaughter size (about 3·5 kg). The experimental fish reared in sea cages were subjected to the challenging conditions typically experienced under commercial production. Salmon receiving the lowest EPA + DHA levels showed lower growth rates in the earlier life stages, but no significant difference in final weights at slaughter. The fatty acid composition of various tissues and organs had remarkably changed. The decreased EPA + DHA in the different tissue membrane phospholipids were typically replaced by pro-inflammatory n -6 fatty acids, most markedly in the skin. The EPA + DHA levels were maintained at a higher level in the liver and erythrocytes than in the muscle, intestine and skin. After delousing at high water temperatures, the mortality rates were 63, 52 and 16 % in the salmon fed 2, 10 and 17 g/kg EPA + DHA. Low EPA + DHA levels also increased the liver, intestinal and visceral fat amount, reduced intervertebral space and caused mid-intestinal hyper-vacuolisation. Thus, 10 g/kg EPA + DHA in the Atlantic salmon diet, a level previously regarded as sufficient, was found to be too low to maintain fish health under demanding environmental conditions in sea cages.

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

    Science.gov (United States)

    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.

  7. Structural alterations in embryos and alevins of the Atlantic salmon, Salmo salar 1. , induced by continuous or short-term exposure to acidic levels of pH

    Energy Technology Data Exchange (ETDEWEB)

    Daye, P.G.; Garside, E.T.

    1980-01-01

    Embryos of the Atlantic Salmon, salmo salar l., were incubated continuously from fertilization, at pH 6.8 (control), 5.0, 4.5, 4.3, 4.0, and 3.7, at 5-6 degrees C. The subsequent alvins in these environments were maintained at these levels for 40 days after hatching. Generally, lethal and sublethal injuries were separable only as to degree and distribution. Sublethal alterations occurred in the integument, gill blood, and blood vascular structures of all live alevins incubated at pH 5.0 and lower. At pH 4.5 and lower, injuries also occurred in brain, optic retina, kidney, and spleen. Some tissue regeneration occurred in the embryonal rudimentary integument at pH 4.5 and lower. Regeneration also occurred but to a lesser degree in pseudobranch, kidney, spleen, and erythrocytes. Injury of the integument was the apparent cause of death in prehatching embryos since it is the major site of respiration and ion exchange. As gills expand in posthatching alevins, they assume these functions and destruction of branchial epithelium then becomes the prime cause of death. The nature of cell injury and consequent dysgenesis at tissue and organ levels are not ascribable uniquely to acidic stress. Some injuries are similar to those caused variously by heavy metals, detergents, halogenated organic compounds, some petroleum fractions, and chronic and acute high temperature in postalevin stages of several species of fish.

  8. Precision-Cut Liver Slices of Salmo salar as a tool to investigate the oxidative impact of CYP1A-mediated PCB 126 and 3-methylcholanthrene metabolism.

    Science.gov (United States)

    Lemaire, Benjamin; Beck, Michaël; Jaspart, Mélanie; Debier, Cathy; Calderon, Pedro Buc; Thomé, Jean-Pierre; Rees, Jean-François

    2011-02-01

    Fish isolated cell systems have long been used to predict in vivo toxicity of man-made chemicals. In present study, we tested the suitability of Precision-Cut Liver Slices (PCLS) as an alternative to these models that allows the evaluation of a global tissue response to toxicants, to investigate oxidative stress response to cytochrome P450 1A (CYP1A) induction in fish liver. PCLS of Salmo salar were exposed for 21 h to increasing doses of 3-methylcholanthrene (3-MC) and Polychlorobiphenyl 126 (PCB 126). 3-MC (25 μM) strongly induced CYP1A transcription. In dose-response analysis (25-100 μM), EROD activity was strongly increased at intermediate 3-MC concentrations. We found the counter-intuitive decline of EROD at the highest 3-MC doses to result from reversible competition with ethoxyresorufin. No increases of H(2)O(2) production, antioxidant enzymes activities or oxidative damage to lipids were found with 3-MC treatments. PCLS subjected to PCB 126 (2-200 nM) showed increased contamination levels and a parallel increased CYP1A mRNA synthesis and EROD activity. H(2)O(2) production tended to increase but no oxidative damage to lipids was found. As antioxidant enzymes activities declined at the highest PCB 126 dose, it is suggested that longer incubation periods could be required to generate oxidative stress in PCLS. Copyright © 2010 Elsevier Ltd. All rights reserved.

  9. a salar elahi

    Indian Academy of Sciences (India)

    Home; Journals; Pramana – Journal of Physics. A SALAR ELAHI. Articles written in Pramana – Journal of Physics. Volume 87 Issue 5 November 2016 pp 81 Regular. Analysis of tokamak plasma confinement modes using the fast Fourier transformation · S R MIRMOEINI A SALAR ELAHI M GHORANNEVISS · More Details ...

  10. Chronic dietary mercury exposure causes oxidative stress, brain lesions, and altered behaviour in Atlantic salmon (Salmo salar) parr

    International Nuclear Information System (INIS)

    Berntssen, Marc H.G.; Aatland, Aase; Handy, Richard D.

    2003-01-01

    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 -1 DW) or methylmercury chloride (0, 5, or 10 mg Hg kg -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 -1 by the end of the experiment, and inorganic mercury accumulated significantly in the brain only at 100 mg kg -1 exposure levels. No mortality or growth reduction was observed in any of the exposure groups. Fish fed 5 mg kg -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 -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 -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 -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 exposure concentrations. Doses of dietary

  11. Oil from transgenic Camelina sativa containing over 25 % n-3 long-chain PUFA as the major lipid source in feed for Atlantic salmon (Salmo salar).

    Science.gov (United States)

    Betancor, Mónica B; Li, Keshuai; Bucerzan, Valentin S; Sprague, Matthew; Sayanova, Olga; Usher, Sarah; Han, Lihua; Norambuena, Fernando; Torrissen, Ole; Napier, Johnathan A; Tocher, Douglas R; Olsen, Rolf E

    2018-06-01

    Facing a bottleneck in the growth of aquaculture, and a gap in the supply and demand of the highly beneficial n-3 long-chain PUFA (LC-PUFA), sustainable alternatives to traditional marine-based feeds are required. Therefore, in the present trial, a novel oil obtained from a genetically engineered oilseed crop, Camelina sativa, that supplied over 25 % n-3 LC-PUFA was tested as a sole dietary-added lipid source in Atlantic salmon (Salmo salar) feed. Three groups of fish were fed three experimental diets for 12 weeks with the same basal composition and containing 20 % added oil supplied by either a blend of fish oil and rapeseed oil (1:3) (COM) reflecting current commercial formulations, wild-type Camelina oil (WCO) or the novel transgenic Camelina oil (TCO). There were no negative effects on the growth, survival rate or health of the fish. The whole fish and flesh n-3 LC-PUFA levels were highest in fish fed TCO, with levels more than 2-fold higher compared with those of fish fed the COM and WCO diets, respectively. Diet TCO had no negative impacts on the evaluated immune and physiological parameters of head kidney monocytes. The transcriptomic responses of liver and mid-intestine showed only mild effects on metabolism genes. Overall, the results clearly indicated that the oil from transgenic Camelina was highly efficient in supplying n-3 LC-PUFA providing levels double that obtained with a current commercial standard, and similar to those a decade ago before substantial dietary fishmeal and oil replacement.

  12. 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

  13. Assessment of a land-locked Atlantic salmon (Salmo salar L.) population as a potential genetic resource with a focus on long-chain polyunsaturated fatty acid biosynthesis.

    Science.gov (United States)

    Betancor, M B; Olsen, R E; Solstorm, D; Skulstad, O F; Tocher, D R

    2016-03-01

    The natural food for Atlantic salmon (Salmo salar) in freshwater has relatively lower levels of omega-3 (n-3) long-chain polyunsaturated fatty acids (LC-PUFA) than found in prey for post-smolt salmon in seawater. Land-locked salmon such as the Gullspång population feed exclusively on freshwater type lipids during its entire life cycle, a successful adaptation derived from divergent evolution. Studying land-locked populations may provide insights into the molecular and genetic control mechanisms that determine and regulate n-3 LC-PUFA biosynthesis and retention in Atlantic salmon. A two factorial study was performed comparing land-locked and farmed salmon parr fed diets formulated with fish or rapeseed oil for 8 weeks. The land-locked parr had higher capacity to synthesise n-3 LC-PUFA as indicated by higher expression and activity of desaturase and elongase enzymes. The data suggested that the land-locked salmon had reduced sensitivity to dietary fatty acid composition and that dietary docosahexaenoic acid (DHA) did not appear to suppress expression of LC-PUFA biosynthetic genes or activity of the biosynthesis pathway, probably an evolutionary adaptation to a natural diet lower in DHA. Increased biosynthetic activity did not translate to enhanced n-3 LC-PUFA contents in the flesh and diet was the only factor affecting this parameter. Additionally, high lipogenic and glycolytic potentials were found in land-locked salmon, together with decreased lipolysis which in turn could indicate increased use of carbohydrates as an energy source and a sparing of lipid. Copyright © 2015 Elsevier B.V. All rights reserved.

  14. Terrestrial liming to promote Atlantic Salmon recovery in Nova Scotia - approaches needed and knowledge gained after a trial application

    Science.gov (United States)

    Sterling, S. M.; Angelidis, C.; Armstrong, M.; Biagi, K. M.; Clair, T. A.; Jackson, N.; Breen, A.

    2014-09-01

    Populations of Atlantic salmon (Salmo salar) in Southwest Nova Scotia (SWNS) have plummeted since the 1980s. Acidification is considered a main threat to this population. The lakes and streams of SWNS were among the most heavily acidified in North America during the last century and calcium levels are predicted to continue to fall in coming decades. One of the most promising mitigation options to reduce the risk of extirpation of the SWNS Salmo salar is terrestrial liming; however, both the chemistry of SWNS rivers, and effective strategies for terrestrial liming in SWNS are poorly understood. Here we have launched the first terrestrial liming study in Nova Scotia, employing a test hydrologic source area liming strategy in a 5 ha experimental catchment in SWNS, Maria Brook; we apply an average local application rate of 13 t ha-1 to 10% of the 47 ha catchment. We employ high frequency stream monitoring to complement grab sampling to identify which constituents pose a threat to Salmo salar and to identify strategies for larger scale terrestrial liming that would fit the local conditions. Results indicate that the water chemistry conditions are currently at toxic levels for Salmo salar throughout the year, with levels of ionic aluminium exceeding toxic thresholds almost 100% of the time. The stream chemistry in Maria Brook is remarkably similar to pre-recovery conditions in other heavily acidified watersheds, such as Birkenes in Norway. Our results support the hypothesis that there has been no recovery from acidification in SWNS. Results from the first year of post-liming do not show an improvement in stream chemistry levels, and further lime application is needed to improve the water chemistry conditions to needed levels for the recovery of Salmo salar.

  15. Transgene and immune gene expression following intramuscular injection of Atlantic salmon (Salmo salar L.) with DNA-releasing PLGA nano- and microparticles.

    Science.gov (United States)

    Hølvold, Linn Benjaminsen; Fredriksen, Børge N; Bøgwald, Jarl; Dalmo, Roy A

    2013-09-01

    The use of poly-(D,L-lactic-co-glycolic) acid (PLGA) particles as carriers for DNA delivery has received considerable attention in mammalian studies. DNA vaccination of fish has been shown to elicit durable transgene expression, but no reports exist on intramuscular administration of PLGA-encapsulated plasmid DNA (pDNA). We injected Atlantic salmon (Salmo salar L.) intramuscularly with a plasmid vector containing a luciferase (Photinus pyralis) reporter gene as a) naked pDNA, b) encapsulated into PLGA nano- (~320 nm) (NP) or microparticles (~4 μm) (MP), c) in an oil-based formulation, or with empty particles of both sizes. The ability of the different pDNA-treatments to induce transgene expression was analyzed through a 70-day experimental period. Anatomical distribution patterns and depot effects were determined by tracking isotope labeled pDNA. Muscle, head kidney and spleen from all treatment groups were analyzed for proinflammatory cytokines (TNF-α, IL-1β), antiviral genes (IFN-α, Mx) and cytotoxic T-cell markers (CD8, Eomes) at mRNA transcription levels at days 1, 2, 4 and 7. Histopathological examinations were performed on injection site samples from days 2, 7 and 30. Injection of either naked pDNA or the oil-formulation was superior to particle treatments for inducing transgene expression at early time-points. Empty particles of both sizes were able to induce proinflammatory immune responses as well as degenerative and inflammatory pathology at the injection site. Microparticles demonstrated injection site depots and an inflammatory pathology comparable to the oil-based formulation. In comparison, the distribution of NP-encapsulated pDNA resembled that of naked pDNA, although encapsulation into NPs significantly elevated the expression of antiviral genes in all tissues. Together the results indicate that while naked pDNA is most efficient for inducing transgene expression, the encapsulation of pDNA into NPs up-regulates antiviral responses that could be

  16. 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

  17. Effects of dehulling, steam-cooking and microwave-irradiation on digestive value of white lupin (Lupinus albus) seed meal for rainbow trout (Oncorhynchus mykiss) and Atlantic salmon (Salmo salar).

    Science.gov (United States)

    Saez, Patricio; Borquez, Aliro; Dantagnan, Patricio; Hernández, Adrián

    2015-01-01

    A digestibility trial was conducted to assess the effect of dehulling, steam-cooking and microwave-irradiation on the apparent digestibility of nutrients in white lupin (Lupinus albus) seed meal when fed to rainbow trout (Oncorhynchus mykiss) and Atlantic salmon (Salmo salar). Six ingredients, whole lupin seed meal (LSM), dehulled LSM, dehulled LSM steam-cooked for 15 or 45 min (SC15 and SC45, respectively) and LSM microwave-irradiated at 375 or 750 W (MW375 and MW750, respectively), were evaluated for digestibility of dry matter, crude protein (CP), lipids, nitrogen-free extractives (NFE) and gross energy (GE). The diet-substitution approach was used (70% reference diet + 30% test ingredient). Faeces from each tank were collected using a settlement column. Dehulled LSM showed higher levels of proximate components (except for NFE and crude fibre), GE and phosphorus in comparison to whole LSM. Furthermore, SC15, SC45, MW375 and MW750 showed slight variations of chemical composition in comparison to dehulled LSM. Results from the digestibility trial indicated that dehulled LSM, SC15, SC45 and MW375 are suitable processing methods for the improvement of nutrients' apparent digestibility coefficient (ADC) in whole LSM. MW750 showed a lower ADC of nutrients (except for CP and lipids for rainbow trout) in comparison with MW350 for rainbow trout and Atlantic salmon, suggesting a heat damage of the ingredient when microwave-irradiation exceeded 350 W.

  18. Baking Reduces Prostaglandin, Resolvin, and Hydroxy-Fatty Acid Content of Farm-Raised Atlantic Salmon (Salmo salar)

    OpenAIRE

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

    2011-01-01

    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 (DHA; 22:6n-3) have known protective effects in the vasculature. It is not known whether 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 sa...

  19. Efficacité d'un exutoire de dévalaison pour smolts de saumon atlantique (Salmo salar L.) et comportement des poissons au niveau de l'aménagement hydroélectrique de Bedous sur le gave d'Aspe étudiés par la technique de marquage-recapture et par radiotélémétrie

    OpenAIRE

    CHANSEAU M.; LARINIER M.; TRAVADE F.

    1999-01-01

    Deux expérimentations ont été conduites en 1995 et 1998 au niveau de la prise d'eau de l'aménagement hydroélectrique de Bedous sur le Gave d'Aspe afin de tester l'efficacité d'un exutoire de dévalaison pour smolts de saumon atlantique (Salmo salar L.). Le dispositif de dévalaison est situé en rive droite à proximité immédiate du plan des grilles. Le débit moyen alimentant l'exutoire a varié au cours de l'étude de 0,4 m3/s à 1,2 m3/s ce qui correspond à 1,6 % à 4,3 % du débit turbiné. Lefficac...

  20. Identification of a low digestibility δ-Conglutin in yellow lupin (Lupinus luteus L.) seed meal for atlantic salmon (Salmo salar L.) by coupling 2D-PAGE and mass spectrometry.

    Science.gov (United States)

    Ogura, Takahiro; Hernández, Adrián; Aizawa, Tomoko; Ogihara, Jun; Sunairi, Michio; Alcaino, Javier; Salvo-Garrido, Haroldo; Maureira-Butler, Iván J

    2013-01-01

    The need of quality protein in the aquaculture sector has forced the incorporation of alternative plant proteins into feeding diets. However, most plant proteins show lower digestibility levels than fish meal proteins, especially in carnivorous fishes. Manipulation of protein content by plant breeding can improve the digestibility rate of plant proteins in fish, but the identification of low digestibility proteins is essential. A reduction of low digestibility proteins will not only increase feed efficiency, but also reduce water pollution. Little is known about specific digestible protein profiles and/or molecular identification of more bioavailable plant proteins in fish diets. In this study, we identified low digestibility L. luteus seed proteins using Atlantic salmon (Salmo salar) crude digestive enzymes in an in vitro assay. Low digestibility proteins were identified by comparing SDS-PAGE banding profiles of digested and non-digested lupin seed proteins. Gel image analysis detected a major 12 kDa protein band in both lupin meal and protein isolate digested products. The 12 kDa was confirmed by 2D-PAGE gels and the extracted protein was analyzed with an ion trap mass spectrometer in tandem mass mode. The MS/MS data showed that the 12 kDa low digestibility protein was a large chain δconglutin, a common seed storage protein of yellow lupin. Comparison of the protein band profiles between lupin meal and protein isolates showed that the isolatation process did not affect the low digestibility of the 12 kDa protein.

  1. Identification of a Low Digestibility δ-Conglutin in Yellow Lupin (Lupinus luteus L.) Seed Meal for Atlantic Salmon (Salmo salar L.) by Coupling 2D-PAGE and Mass Spectrometry

    Science.gov (United States)

    Ogura, Takahiro; Hernández, Adrián; Aizawa, Tomoko; Ogihara, Jun; Sunairi, Michio; Alcaino, Javier; Salvo-Garrido, Haroldo; Maureira-Butler, Iván J.

    2013-01-01

    The need of quality protein in the aquaculture sector has forced the incorporation of alternative plant proteins into feeding diets. However, most plant proteins show lower digestibility levels than fish meal proteins, especially in carnivorous fishes. Manipulation of protein content by plant breeding can improve the digestibility rate of plant proteins in fish, but the identification of low digestibility proteins is essential. A reduction of low digestibility proteins will not only increase feed efficiency, but also reduce water pollution. Little is known about specific digestible protein profiles and/or molecular identification of more bioavailable plant proteins in fish diets. In this study, we identified low digestibility L. luteus seed proteins using Atlantic salmon (Salmo salar) crude digestive enzymes in an in vitro assay. Low digestibility proteins were identified by comparing SDS-PAGE banding profiles of digested and non-digested lupin seed proteins. Gel image analysis detected a major 12 kDa protein band in both lupin meal and protein isolate digested products. The 12 kDa was confirmed by 2D-PAGE gels and the extracted protein was analyzed with an ion trap mass spectrometer in tandem mass mode. The MS/MS data showed that the 12 kDa low digestibility protein was a large chain δconglutin, a common seed storage protein of yellow lupin. Comparison of the protein band profiles between lupin meal and protein isolates showed that the isolatation process did not affect the low digestibility of the 12 kDa protein. PMID:24278278

  2. 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

  3. 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

    2013-08-01

    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. © 2013 Anatomical Society.

  4. Identification of a low digestibility δ-Conglutin in yellow lupin (Lupinus luteus L. seed meal for atlantic salmon (Salmo salar L. by coupling 2D-PAGE and mass spectrometry.

    Directory of Open Access Journals (Sweden)

    Takahiro Ogura

    Full Text Available The need of quality protein in the aquaculture sector has forced the incorporation of alternative plant proteins into feeding diets. However, most plant proteins show lower digestibility levels than fish meal proteins, especially in carnivorous fishes. Manipulation of protein content by plant breeding can improve the digestibility rate of plant proteins in fish, but the identification of low digestibility proteins is essential. A reduction of low digestibility proteins will not only increase feed efficiency, but also reduce water pollution. Little is known about specific digestible protein profiles and/or molecular identification of more bioavailable plant proteins in fish diets. In this study, we identified low digestibility L. luteus seed proteins using Atlantic salmon (Salmo salar crude digestive enzymes in an in vitro assay. Low digestibility proteins were identified by comparing SDS-PAGE banding profiles of digested and non-digested lupin seed proteins. Gel image analysis detected a major 12 kDa protein band in both lupin meal and protein isolate digested products. The 12 kDa was confirmed by 2D-PAGE gels and the extracted protein was analyzed with an ion trap mass spectrometer in tandem mass mode. The MS/MS data showed that the 12 kDa low digestibility protein was a large chain δconglutin, a common seed storage protein of yellow lupin. Comparison of the protein band profiles between lupin meal and protein isolates showed that the isolatation process did not affect the low digestibility of the 12 kDa protein.

  5. Comparison of vaccine efficacy for different antigen delivery systems for infectious pancreatic necrosis virus vaccines in Atlantic salmon (Salmo salar L.) in a cohabitation challenge model.

    Science.gov (United States)

    Munang'andu, Hetron M; Fredriksen, Børge N; Mutoloki, Stephen; Brudeseth, Bjørn; Kuo, Tsun-Yung; Marjara, Inderjit S; Dalmo, Roy A; Evensen, Øystein

    2012-06-08

    Two strains of IPNV made by reverse genetics on the Norwegian Sp strain NVI-015 (GenBank AY379740) backbone encoding the virulent (T(217)A(221)) and avirulent (P(217)T(221)) motifs were used to prepare inactivated whole virus (IWV), nanoparticle vaccines with whole virus, Escherichia coli subunit encoding truncated VP2-TA and VP2-PT, VP2-TA and VP2-PT fusion antigens with putative translocating domains of Pseudomonas aeruginosa exotoxin, and plasmid DNA encoding segment A of the TA strain. Post challenge survival percentages (PCSP) showed that IWV vaccines conferred highest protection (PCSP=42-53) while nanoparticle, sub-unit recombinant and DNA vaccines fell short of the IWV vaccines in Atlantic salmon (Salmo salar L.) postsmolts challenged with the highly virulent Sp strain NVI-015 (TA strain) of IPNV after 560 degree days post vaccination. Antibody levels induced by these vaccines did not show antigenic differences between the virulent and avirulent motifs for vaccines made with the same antigen dose and delivery system after 8 weeks post vaccination. Our findings show that fish vaccinated with less potent vaccines comprising of nanoparticle, DNA and recombinant vaccines got infected much earlier and yielded to higher infection rates than fish vaccinated with IWV vaccines that were highly potent. Ability of the virulent (T(217)A(221)) and avirulent (P(217)T(221)) motifs to limit establishment of infection showed equal protection for vaccines made of the same antigen dose and delivery systems. Prevention of tissue damage linked to viral infection was eminent in the more potent vaccines than the less protective ones. Hence, there still remains the challenge of developing highly efficacious vaccines with the ability to eliminate the post challenge carrier state in IPNV vaccinology. Copyright © 2012 Elsevier Ltd. All rights reserved.

  6. 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

  7. An oil containing EPA and DHA from transgenic Camelina sativa to replace marine fish oil in feeds for Atlantic salmon (Salmo salar L.: Effects on intestinal transcriptome, histology, tissue fatty acid profiles and plasma biochemistry.

    Directory of Open Access Journals (Sweden)

    Mónica B Betancor

    Full Text Available New de novo sources of omega 3 (n-3 long chain polyunsaturated fatty acids (LC-PUFA are required as alternatives to fish oil in aquafeeds in order to maintain adequate levels of the beneficial fatty acids, eicosapentaenoic and docosahexaenoic (EPA and DHA, respectively. The present study investigated the use of an EPA+DHA oil derived from transgenic Camelina sativa in Atlantic salmon (Salmo salar feeds containing low levels of fishmeal (35% and fish oil (10%, reflecting current commercial formulations, to determine the impacts on tissue fatty acid profile, intestinal transcriptome, and health of farmed salmon. Post-smolt Atlantic salmon were fed for 12-weeks with one of three experimental diets containing either a blend of fish oil/rapeseed oil (FO, wild-type camelina oil (WCO or transgenic camelina oil (DCO as added lipid source. The DCO diet did not affect any of the fish performance or health parameters studied. Analyses of the mid and hindgut transcriptomes showed only mild effects on metabolism. Flesh of fish fed the DCO diet accumulated almost double the amount of n-3 LC-PUFA than fish fed the FO or WCO diets, indicating that these oils from transgenic oilseeds offer the opportunity to increase the n-3 LC-PUFA in farmed fish to levels comparable to those found a decade ago.

  8. Predation on Atlantic salmon and sea trout during their first days as postsmolts

    DEFF Research Database (Denmark)

    Dieperink, C.; Bak, B.D.; Pedersen, Lars-Flemming

    2002-01-01

    Radio-tagged smolts of Atlantic salmon Salmo salar and sea trout Salmo trutta were predated heavily by sea birds after crossing the saline limit in the estuary of the River Skjern, Denmark. Most predation took place within the first 9 h after estuarine entry. The field data do not contradict...

  9. Exposure of Atlantic salmon parr (Salmo salar) to a combination of resin acids and a water soluble fraction of diesel fuel oil: A model to investigate the chemical causes of pigmented salmon syndrome

    International Nuclear Information System (INIS)

    Croce, B.; Scottish Environmental Protection Agency, Aberdeen; Stagg, R.M.

    1997-01-01

    Pigmented salmon syndrome is a pollutant-induced hemolytic anemia and hyperbilirubinemia. As part of an investigation of this condition, S2 Atlantic salmon parr (Salmo salar) were exposed to a diesel fuel oil, water soluble fraction (WSF) in combination with a mixture of three resin acids (isopimaric, dehydroabietic, and abietic acids) in a continuous-flow freshwater system. The total nominal concentrations of resin acids in the exposure tanks were 10, 50, and 100 microg/L; the diesel WSF was generated in situ and provided a mean hydrocarbon concentration of 2.0 ± 0.1 mg/L (n = 12) during the 9-d exposure period. Exposure to the diesel WSF alone depressed liver bilirubin UDP-glucuronosyl transferase (UDPGT) activity and induced phenol UDPGT activity. Exposure to the diesel WSF in the absence or presence of resin acids induced liver cytochrome P4501A and increased the concentrations in the plasma of the enzymes lactate dehydrogenase, alkaline phosphatase, and glutamic oxaloacetic transaminase. The combined exposure to diesel WSF with either 50 or 100 microg/L total resin acid caused significant elevations in the concentrations of bilirubin in the plasma and many of these fish had yellow pigmentation on the ventral surface and around the gill arches. The results demonstrate that exposure to combinations of two groups of contaminants can result in the manifestation of toxic effects not apparent from exposure to either of these chemicals in isolation

  10. A description and assessment of the Atlantic salmon (salmo salar) fall pre-smolt migration in relation to the Tobique narrows hydroelectric facility, Tobique River, New Brunswick using radio telemetry

    International Nuclear Information System (INIS)

    Jones, R.A.; Flanagan, J.J.

    2007-01-01

    Atlantic salmon (salmo salar) smolts typically migrate to the ocean in the spring following 2 to 4 years in freshwater. However, in some rivers, migration can also begin in the fall for a small component of the population of known as pre-smolts. These fish do not complete their migration to the ocean in the fall, but rather remain in freshwater, closer to the marine environment, until the following spring when they complete their migration. This report presented the results of a collaborative research project between New Brunswick Power Commission, Fisheries and Oceans Canada, Atlantic Salmon Federation, University of New Brunswick and the Tobique Salmon Protective Association that utilized radio telemetry to study the spatial and temporal movements of fall migrating, wild Atlantic salmon pre-smolts in the upstream and downstream vicinities of the Tobique Narrows Dam. In order to provide an estimation of the fall pre-smolt population migrating from the Tobique River, rotary screw traps were used along with a mark recapture method. It was hoped that the results from this radio tagging experiment would facilitate the establishment of an effective downstream fish passage and/or collection strategies for juvenile salmon. The report described the study area; Tobique Narrows Dam; catches and estimates; radio tagging; fixed radio receivers; and searches. Results were presented for catches and estimates; migration to Arthurette; migration to Tobique Narrows Dam; operating conditions at Tobique Narrows Dam; estimated numbers of pre-smolts up river and down river of the Tobique Narrows Dam; and migration to Beechwood Dam. Recommendations and considerations for future evaluations or research were also presented. 29 refs., 8 tabs., 18 figs., 3 appendices

  11. 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.

  12. 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

  13. 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.

  14. [Evaluation of ten fish species to be included as part of renal diet, due to their protein, phosphorus and fatty acids content].

    Science.gov (United States)

    Castro-González, Maria Isabel; Maafs-Rodríguez, Ana Gabriela; Pérez-Gil Romo, Fernando

    2012-06-01

    Because renal disease is highly complex, its nutritional treatment is complicated and many foods are restricted, including fish because its phosphorus content. The aim of the present study was to analyze ten fillet fish species, commonly consumed in Mexico (Cyprinus carpio carpio, Ophichthus rex, Symphurus elongatus, Eucinostomus entomelas, Chirostoma patzcuaro, Bairdiella chrysoura, Salmo salar Oreochromis urolepis hornorum, Sphyraena guachancho, Istiophorus albicans), to determine their phosphorus (P), protein (Pr), cholesterol, sodium, potassium, vitamins D3 and E, and n-3 PUFA (EPA+DHA) according to the AOAC techniques, in order to identify which species could be included in renal diet; particularly because of their risk:benefit relations (calculated with those results). Protein values ranged from 16.5 to 33.5g/100 g of fillet; the specie with the highest phosphorus contest was Salmo salar, and with the lowest, Symphurus elongatus. EPA+DHA quantity ranged from 79.64 mg/100 g to 1,381.53 mg/100 g. Considering de P/Pr relation recommended to renal patients, all analyzed species (except Salmo salar, Ophichthus rex and Istiophorus albicans) could be included in their diet. As for the P/EPA+DHA relation, the species most recommended to renal patients are Symphurus elongatus, Bairdiella chrysoura and Sphyraena guachancho.

  15. 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

  16. Baltic salmon (Salmo salar) yolk-sac fry mortality is associated with disturbances in the function of hypoxia-inducible transcription factor (HIF-1α) and consecutive gene expression

    International Nuclear Information System (INIS)

    Vuori, Kristiina A.M.; Soitamo, Arto; Vuorinen, Pekka J.; Nikinmaa, Mikko

    2004-01-01

    Baltic salmon (Salmo salar) suffer from abnormally high yolk-sac fry mortality designated as M74-syndrome. In 1990s, 25-80% of salmon females, which ascended rivers to spawn, produced yolk-sac fry suffering from the syndrome. Symptoms of M74-affected fry include neurological disturbances, impaired vascular development and abnormal haemorrhages. The latter symptoms are observed in mammalian embryos if the function of hypoxia inducible transcription factor (HIF-1α), its dimerization partner aryl hydrocarbon nuclear translocator (ARNT) or target gene vascular endothelial growth factor (VEGF) is disturbed. To study the possible involvement of HIF-1α and its target gene VEGF in the development of the syndrome, we collected healthy and M74-affected wild Baltic salmon yolk-sac fry and analyzed HIF-1α mRNA and protein expression, HIF-1α DNA-binding, target gene VEGF protein expression, and blood vessel density in both groups at different stages of yolk-sac fry development. In addition, since Baltic salmon females contain organochlorine contaminants, which have been suggested to be the cause of M74 syndrome via the aryl hydrocarbon receptor (AhR)-dependent gene expression pathway, we studied AhR protein expression, AhR DNA-binding and target gene CYP1A protein expression. Since the parents of both healthy and M74-affected wild fry will have experienced the organochlorine load from the Baltic Sea, hatchery-reared fry were included in the studies as an additional control. The results show that the vascular defects observed in fry suffering from M74 are associated with reduced DNA-binding activity of HIF-1α and subsequent downregulation of its target gene vascular endothelial growth factor (VEGF). In addition, also AhR function is decreased in diseased fry making it unlikely that symptoms of M74-affected fry would be caused by an upregulation of xenobiotically induced AhR-dependent gene expression pathway

  17. Potential physiological effects of pharmaceutical compounds in Atlantic salmon (Salmo salar) implied by transcriptomic analysis.

    Science.gov (United States)

    Hampel, Miriam; Alonso, Esteban; Aparicio, Irene; Bron, James E; Santos, Juan Luis; Taggart, John B; Leaver, Michael J

    2010-05-01

    Pharmaceuticals are emerging pollutants widely used in everyday urban activities which can be detected in surface, ground, and drinking waters. Their presence is derived from consumption of medicines, disposal of expired medications, release of treated and untreated urban effluents, and from the pharmaceutical industry. Their growing use has become an alarming environmental problem which potentially will become dangerous in the future. However, there is still a lack of knowledge about long-term effects in non-target organisms as well as for human health. Toxicity testing has indicated a relatively low acute toxicity to fish species, but no information is available on possible sublethal effects. This study provides data on the physiological pathways involved in the exposure of Atlantic salmon as representative test species to three pharmaceutical compounds found in ground, surface, and drinking waters based on the evaluation of the xenobiotic-induced impairment resulting in the activation and silencing of specific genes. Individuals of Atlantic salmon (Salmo salar) parr were exposed during 5 days to environmentally relevant concentrations of three representative pharmaceutical compounds with high consumption rates: the analgesic acetaminophen (54.77+/-34.67 microg L(-1)), the anticonvulsant carbamazepine (7.85+/-0.13 microg L(-1)), and the beta-blocker atenolol (11.08+/-7.98 microg L(-1)). Five immature males were selected for transcriptome analysis in brain tissues by means of a 17k salmon cDNA microarray. For this purpose, mRNA was isolated and reverse-transcribed into cDNA which was labeled with fluorescent dyes and hybridized against a common pool to the arrays. Lists of significantly up- and down-regulated candidate genes were submitted to KEGG (Kyoto Encyclopedia of Genes and Genomes) in order to analyze for induced pathways and to evaluate the usefulness of this method in cases of not completely annotated test organisms. Exposure during 5 days to

  18. Physiological, molecular, and cellular mechanisms of impaired seawater tolerance following exposure of Atlantic salmon, Salmo salar, smolts to acid and aluminum

    Energy Technology Data Exchange (ETDEWEB)

    Monette, Michelle Y., E-mail: michelle.monette@yale.edu [Organismic and Evolutionary Biology Program, University of Massachusetts, Amherst, MA 01003 (United States); USGS, Conte Anadromous Fish Research Center, Turners Falls, MA 01376 (United States); Yada, Takashi [Freshwater Fisheries Research Department, National Research Institute of Fisheries Science, Nikko (Japan); Matey, Victoria [Department of Biology, San Diego State University, San Diego, CA 92182 (United States); McCormick, Stephen D. [Organismic and Evolutionary Biology Program, University of Massachusetts, Amherst, MA 01003 (United States); USGS, Conte Anadromous Fish Research Center, Turners Falls, MA 01376 (United States)

    2010-08-01

    We examined the physiological, molecular, and cellular mechanisms of impaired ion regulation in Atlantic salmon, Salmo salar, smolts following acute acid and aluminum (Al) exposure. Smolts were exposed to: control (pH 6.5, 3.4 {mu}g l{sup -1} Al), acid and low Al (LAl: pH 5.4, 11 {mu}g l{sup -1} Al), acid and moderate Al (MAl: pH 5.3, 42 {mu}g l{sup -1} Al), and acid and high Al (HAl: pH 5.4, 56 {mu}g l{sup -1} Al) for two and six days. At each time-point, smolts were sampled directly from freshwater treatment tanks and after a 24 h seawater challenge. Exposure to acid/MAl and acid/HAl led to accumulation of gill Al, substantial alterations in gill morphology, reduced gill Na{sup +}/K{sup +}-ATPase (NKA) activity, and impaired ion regulation in both freshwater and seawater. Exposure to acid/MAl for six days also led to a decrease in gill mRNA expression of the apical Cl{sup -} channel (cystic fibrosis transmembrane conductance regulator I), increased apoptosis upon seawater exposure, an increase in the surface expression of mitochondria-rich cells (MRCs) within the filament epithelium of the gill, but reduced abundance of gill NKA-positive MRCs. By contrast, smolts exposed to acid and the lowest Al concentration exhibited minor gill Al accumulation, slight morphological modifications in the gill, and impaired seawater tolerance in the absence of a detectable effect on freshwater ion regulation. These impacts were accompanied by decreased cell proliferation, a slight increase in the surface expression of MRCs within the filament epithelium, but no impact on gill apoptosis or total MRC abundance was observed. However, MRCs in the gills of smolts exposed to acid/LAl exhibited morphological alterations including decreased size, staining intensity, and shape factor. We demonstrate that the seawater tolerance of Atlantic salmon smolts is extremely sensitive to acute exposure to acid and low levels of Al, and that the mechanisms underlying this depend on the time

  19. Physiological, molecular, and cellular mechanisms of impaired seawater tolerance following exposure of Atlantic salmon, Salmo salar, smolts to acid and aluminum

    International Nuclear Information System (INIS)

    Monette, Michelle Y.; Yada, Takashi; Matey, Victoria; McCormick, Stephen D.

    2010-01-01

    We examined the physiological, molecular, and cellular mechanisms of impaired ion regulation in Atlantic salmon, Salmo salar, smolts following acute acid and aluminum (Al) exposure. Smolts were exposed to: control (pH 6.5, 3.4 μg l -1 Al), acid and low Al (LAl: pH 5.4, 11 μg l -1 Al), acid and moderate Al (MAl: pH 5.3, 42 μg l -1 Al), and acid and high Al (HAl: pH 5.4, 56 μg l -1 Al) for two and six days. At each time-point, smolts were sampled directly from freshwater treatment tanks and after a 24 h seawater challenge. Exposure to acid/MAl and acid/HAl led to accumulation of gill Al, substantial alterations in gill morphology, reduced gill Na + /K + -ATPase (NKA) activity, and impaired ion regulation in both freshwater and seawater. Exposure to acid/MAl for six days also led to a decrease in gill mRNA expression of the apical Cl - channel (cystic fibrosis transmembrane conductance regulator I), increased apoptosis upon seawater exposure, an increase in the surface expression of mitochondria-rich cells (MRCs) within the filament epithelium of the gill, but reduced abundance of gill NKA-positive MRCs. By contrast, smolts exposed to acid and the lowest Al concentration exhibited minor gill Al accumulation, slight morphological modifications in the gill, and impaired seawater tolerance in the absence of a detectable effect on freshwater ion regulation. These impacts were accompanied by decreased cell proliferation, a slight increase in the surface expression of MRCs within the filament epithelium, but no impact on gill apoptosis or total MRC abundance was observed. However, MRCs in the gills of smolts exposed to acid/LAl exhibited morphological alterations including decreased size, staining intensity, and shape factor. We demonstrate that the seawater tolerance of Atlantic salmon smolts is extremely sensitive to acute exposure to acid and low levels of Al, and that the mechanisms underlying this depend on the time-course and severity of Al exposure. We propose

  20. Physiological, molecular, and cellular mechanisms of impaired seawater tolerance following exposure of Atlantic salmon, Salmo salar, smolts to acid and aluminum

    Science.gov (United States)

    Monette, M.Y.; Yada, T.; Matey, V.; McCormick, S.D.

    2010-01-01

    We examined the physiological, molecular, and cellular mechanisms of impaired ion regulation in Atlantic salmon, Salmo salar, smolts following acute acid and aluminum (Al) exposure. Smolts were exposed to: control (pH 6.5, 3.4??gl-1 Al), acid and low Al (LAl: pH 5.4, 11??gl-1 Al), acid and moderate Al (MAl: pH 5.3, 42??gl-1 Al), and acid and high Al (HAl: pH 5.4, 56??gl-1 Al) for two and six days. At each time-point, smolts were sampled directly from freshwater treatment tanks and after a 24h seawater challenge. Exposure to acid/MAl and acid/HAl led to accumulation of gill Al, substantial alterations in gill morphology, reduced gill Na+/K+-ATPase (NKA) activity, and impaired ion regulation in both freshwater and seawater. Exposure to acid/MAl for six days also led to a decrease in gill mRNA expression of the apical Cl- channel (cystic fibrosis transmembrane conductance regulator I), increased apoptosis upon seawater exposure, an increase in the surface expression of mitochondria-rich cells (MRCs) within the filament epithelium of the gill, but reduced abundance of gill NKA-positive MRCs. By contrast, smolts exposed to acid and the lowest Al concentration exhibited minor gill Al accumulation, slight morphological modifications in the gill, and impaired seawater tolerance in the absence of a detectable effect on freshwater ion regulation. These impacts were accompanied by decreased cell proliferation, a slight increase in the surface expression of MRCs within the filament epithelium, but no impact on gill apoptosis or total MRC abundance was observed. However, MRCs in the gills of smolts exposed to acid/LAl exhibited morphological alterations including decreased size, staining intensity, and shape factor. We demonstrate that the seawater tolerance of Atlantic salmon smolts is extremely sensitive to acute exposure to acid and low levels of Al, and that the mechanisms underlying this depend on the time-course and severity of Al exposure. We propose that when smolts are

  1. Intestinal cellular localization of PCNA protein and CYP1A mRNA in Atlantic salmon Salmo salar L. exposed to a model toxicant

    Directory of Open Access Journals (Sweden)

    Olsvik Pål A

    2009-03-01

    Full Text Available Abstract Background The aim of the study was to examine the intestinal cellular localization of proliferating cell nuclear antigen (PCNA and cytochrome P450 A1 (CYP1A expression in Atlantic salmon Salmo salar L. exposed to a model toxicant. The stress response was induced by intraperitoneal injection of four salmon with a single dose (50 mg/kg of the CYP1A inducer β-naphthoflavone (BNF and intestinal tissue (mid and distal intestine; MI and DI was sampled seven days later. Samples for histology and gene transcription analysis were collected from four exposed fish and four control fish. PCNA was assessed by immunohistochemistry, CYP1A mRNA was studied by in situ hybridization (ISH and finally the transcription of five genes was quantified by real-time quantitative RT-PCR (real-time RT-PCR; two detoxifying genes (CYP1A and glutathione S-transferase; GST, a stress marker gene (heat shock protein 70; HSP70, PCNA and a gene marker of apoptosis (caspase 6A. Results PCNA protein and CYP1A mRNA were successfully localized in the intestinal cells (MI of both experimental groups. At the cellular level, BNF significantly lowered intestinal cell proliferation and increased the CYP1A mRNA levels compared to the control group. The real-time RT-PCR data, which showed an increased mRNA expression both in the MI and DI of 139- and 62-fold, respectively, confirmed the increased cellular CYP1A mRNA levels detected using ISH. HSP70 expression was also up-regulated in the exposed fish. The other examined genes did not show any differential regulation in the experimental fish group. Conclusion This study showed that CYP1A mRNA had a specific intestinal cellular transcription pattern in Atlantic salmon exposed to BNF. At the cellular level CYP1A mRNA expression was always observed at or around the cell nucleus close to the basolateral cell membrane and at the tissue level CYP1A mRNA expression was most frequently observed in the basal and apex area of the intestinal

  2. Investigating the influence of nitrate nitrogen on post-smolt Atlantic salmon Salmo salar reproductive physiology in water recirculation aquaculture systems

    Science.gov (United States)

    Good, Christopher; Davidson, John; Iwanowicz, Luke R.; Meyer, Michael T.; Dietze, Julie E.; Kolpin, Dana W.; Marancik, David; Birkett, Jill; Williams, Christina; Summerfelt, Steven T.

    2017-01-01

    A major issue affecting land-based, closed containment Atlantic salmon Salmo salar growout production in water recirculation aquaculture systems (RAS) is precocious male maturation, which can negatively impact factors such as feed conversion, fillet yield, and product quality. Along with other water quality parameters, elevated nitrate nitrogen (NO3-N) has been shown to influence the reproductive development and endogenous sex steroid production in a number of aquatic animal species, including Atlantic salmon. We sought to determine whether elevated NO3-N in RAS can influence early maturation in post-smolt Atlantic salmon in an 8-month trial in replicated freshwater RAS. Post-smolt Atlantic salmon (102 ± 1 g) were stocked into six RAS, with three RAS randomly selected for dosing with high NO3-N (99 ± 1 mg/L) and three RAS set for low NO3-N (10 ± 0 mg/L). At 2-, 4-, 6-, and 8-months post-stocking, 5 fish were randomly sampled from each RAS, gonadosomatic index(GSI) data were collected, and plasma was sampled for 11-ketotestosterone(11-KT) quantification. At 4- and 8-months post-stocking, samples of culture tank and spring water (used as “makeup” or replacement water) were collected and tested for a suite of 42 hormonally active compounds using liquid chromatography/mass spectrometry, as well as for estrogenicity using the bioluminescent yeast estrogen screen (BLYES) reporter system. Finally, at 8-months post-stocking 8–9 salmon were sampled from each RAS for blood gas and chemistry analyses, and multiple organ tissues were sampled for histopathology evaluation. Overall, sexually mature males were highly prevalent in both NO3-N treatment groups by study’s end, and there did not appear to be an effect of NO3-N on male maturation prevalence based on grilse identification, GSI, and 11-KT results, indicating that other culture parameters likely instigated early maturation. No important differences were noted between treatment groups for

  3. 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

  4. Functional genomics reveals increases in cholesterol biosynthetic genes and highly unsaturated fatty acid biosynthesis after dietary substitution of fish oil with vegetable oils in Atlantic salmon (Salmo salar

    Directory of Open Access Journals (Sweden)

    Bron James E

    2008-06-01

    Full Text Available Abstract Background There is an increasing drive to replace fish oil (FO in finfish aquaculture diets with vegetable oils (VO, driven by the short supply of FO derived from wild fish stocks. However, little is known of the consequences for fish health after such substitution. The effect of dietary VO on hepatic gene expression, lipid composition and growth was determined in Atlantic salmon (Salmo salar, using a combination of cDNA microarray, lipid, and biochemical analysis. FO was replaced with VO, added to diets as rapeseed (RO, soybean (SO or linseed (LO oils. Results Dietary VO had no major effect on growth of the fish, but increased the whole fish protein contents and tended to decrease whole fish lipid content, thus increasing the protein:lipid ratio. Expression levels of genes of the highly unsaturated fatty acid (HUFA and cholesterol biosynthetic pathways were increased in all vegetable oil diets as was SREBP2, a master transcriptional regulator of these pathways. Other genes whose expression was increased by feeding VO included those of NADPH generation, lipid transport, peroxisomal fatty acid oxidation, a marker of intracellular lipid accumulation, and protein and RNA processing. Consistent with these results, HUFA biosynthesis, hepatic β-oxidation activity and enzymic NADPH production were changed by VO, and there was a trend for increased hepatic lipid in LO and SO diets. Tissue cholesterol levels in VO fed fish were the same as animals fed FO, whereas fatty acid composition of the tissues largely reflected those of the diets and was marked by enrichment of 18 carbon fatty acids and reductions in 20 and 22 carbon HUFA. Conclusion This combined gene expression, compositional and metabolic study demonstrates that major lipid metabolic effects occur after replacing FO with VO in salmon diets. These effects are most likely mediated by SREBP2, which responds to reductions in dietary cholesterol. These changes are sufficient to maintain

  5. Transcriptome sequencing of Atlantic salmon (Salmo salar L.) notochord prior to development of the vertebrae provides clues to regulation of positional fate, chordoblast lineage and mineralisation.

    Science.gov (United States)

    Wang, Shou; Furmanek, Tomasz; Kryvi, Harald; Krossøy, Christel; Totland, Geir K; Grotmol, Sindre; Wargelius, Anna

    2014-02-19

    In teleosts such as Atlantic salmon (Salmo salar L.), segmentation and subsequent mineralisation of the notochord during embryonic stages are essential for normal vertebrae formation. However, the molecular mechanisms leading to segmentation and mineralisation of the notochord are poorly understood. The aim of this study was to identify genes/pathways acting in gradients over time and along the anterior-posterior axis during notochord segmentation and immediately prior to mineralisation of the vertebral bodies in Atlantic salmon. Notochord samples were collected from unsegmented, pre-segmented and segmented developmental stages. In each stage, the cellular core of the notochord was cut into three pieces along the longitudinal axis (anterior, mid, posterior). RNA was sequenced (22 million pair-end 100 bp/ library) and mapped to the salmon genome. 66569 transcripts were predicted and 55775 were annotated. In order to identify possible gradients leading to segmentation of the notochord, all 71 notochord-expressed hox genes were investigated, most of them displaying a typical anterior-posterior expression pattern along the notochord axis. The clustering of hox genes revealed a pattern that could be related to notochord segmentation. We further investigated how mineralisation is initiated in the notochord, and several factors related to chondrogenic lineage were identified (sox9, sox5, sox6, tgfb3, ihhb and col2a1), suggesting a cartilage-like character of the notochord. KEGG analysis of differentially expressed genes between stages revealed down-regulation of pathways associated with ECM, cell division, metabolism and development at onset of notochord segmentation. This implies that inhibitory signals produce segmentation of the notochord. One such potential inhibitory signal was identified, col11a2, which was detected in segments of non-mineralising notochord. An incomplete salmon genome was successfully used to analyse RNA-seq data from the cellular core of the

  6. Digestive efficiency, free amino acid pools and quality of growth performance in Atlantic salmon (Salmo salar L.) affected by light regimes and vaccine types.

    Science.gov (United States)

    Rungruangsak-Torrissen, Krisna; Sunde, Jan; Berg, Arne Erik; Nordgarden, Ulla; Fjelldal, Per Gunnar; Oppedal, Frode

    2009-06-01

    This study comprised the results of three different seawater trials using unique combination of techniques to study protease digestive efficiency and growth performance quality to illustrate the effects of light regimes and vaccine types in Atlantic salmon (Salmo salar L.). Fish with higher growth had higher trypsin (T) and chymotrypsin (C) specific activities with higher T/C ratio or slope T/C ratio [calculated from the regression between trypsin (y) and chymotrypsin (x) specific activities] in the pyloric caeca. The T/C ratios indicated fish growth rates over a period of 1-2 months, while the slope T/C ratios indicated fish growth rates at sampling. Adaptation period for adjustment to the new environment of continuous light was 70 days, indicated by the differences in trypsin specific activities and the crossing of slope T/C ratio regressions following with the changes in growth rate directions between the control and the treated group. Vaccine types affected fish vertebral growth, and additional continuous light enhanced the impact of vaccines on fish growth during springtime, indicated by differences in slope T/C ratios. Continuous light stimulated fish growth during winter to spring, when the natural day length was short, without significantly changing white muscle and oocyte qualities in the fish of about 500 g, except for significantly increased white muscle RNA concentration. Continuous light also reduced fish growth rate later during summer, when the natural day length was long, by precedently decreasing the T/C ratio in late spring. Interestingly, plasma levels of free lysine related to tryptic digestion were correlated with trypsin specific activity levels. Continuous light caused higher levels of most free amino acids (FAA) involved in nitrogen metabolism, higher incorporation of essential FAA for protein synthesis, and higher protein turnover rate (free hydroxyproline levels) in both plasma and white muscle. However, continuous light did not affect

  7. Download this PDF file

    African Journals Online (AJOL)

    DR. AMINU

    TOTAL CAROTENOIDS, TOCOPHEROLS AND FREE FATTY ACIDS LEVELS ... Acid(FFA) levels of oils produced from small scale mills and to evaluate their ..... and lipid contents in muscle of atlantic Salmo. Salar, transferred to seawater as.

  8. Development and bioefficacy study of plant-based proteins diets for ...

    African Journals Online (AJOL)

    SARAH

    2015-10-31

    Oct 31, 2015 ... Keywords: Clarias gariepinus, lactic acids fermentation, malting, plant protein. INTRODUCTION ..... Atlantic salmon (Salmo salar) grow on diets devoid of ... and Fatty Acid Profiles of the Fillets of Channel. Catfish Reared on ...

  9. Potential of bacterial fermentation as a biosafe method of improving ...

    African Journals Online (AJOL)

    STORAGESEVER

    2009-05-04

    May 4, 2009 ... the organic acid content of fermented feeds has been reported to improve ..... fatty acid and ethanol concentration resulting from the natural fermentation of ..... energy in Atlantic salmon (Salmo salar L.) diets. Aquaculture 210:.

  10. 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.

  11. Growth and development of skeletal anomalies in diploid and triploid Atlantic salmon (Salmo salar) fed phosphorus-rich diets with fish meal and hydrolyzed fish protein

    Science.gov (United States)

    Puvanendran, Velmurugu; Riesen, Guido; Seim, Rudi Ripman; Hagen, Ørjan; Martínez-Llorens, Silvia; Falk-Petersen, Inger-Britt; Fernandes, Jorge M. O.; Jobling, Malcolm

    2018-01-01

    Diploid and triploid Atlantic salmon, Salmo salar were fed high-protein, phosphorus-rich diets (56–60% protein; ca 18g phosphorus kg-1 diet) whilst being reared at low temperature from start-feeding until parr-smolt transformation. Performances of salmon fed diets based on fish meal (STD) or a mix of fishmeal and hydrolysed fish proteins (HFM) as the major protein sources were compared in terms of mortality, diet digestibility, growth and skeletal deformities. Separate groups of diploids and triploids were reared in triplicate tanks (initially 3000 fish per tank; tank biomass ca. 620 g) from 0–2745 degree-days post-start feeding (ddPSF). Growth metrics (weight, length, condition factor) were recorded at ca. 4 week intervals, external signs of deformities to the operculum, jaws and spinal column were examined in parr sampled at 1390 ddPSF, and external signs of deformity and vertebral anomalies (by radiography) were examined in fish sampled at the end of the trial (2745 ddPSF). The triploid salmon generally had a lower mass per unit length, i.e. lower condition factor, throughout the trial, but this did not seem to reflect any consistent dietary or ploidy effects on either dietary digestibility or the growth of the fish. By the end of the trial fish in all treatment groups had achieved a weight of 50+ g, and had completed the parr-smolt transformation. The triploids had slightly, but significantly, fewer vertebrae (Triploids STD 58.74 ± 0.10; HFM 58.68 ± 0.05) than the diploids (Diploids STD 58.97 ± 0.14; HFM 58.89 ± 0.01), and the incidence of skeletal (vertebral) abnormalities was higher in triploids (Triploids STD 31 ± 0.90%; HFM 15 ± 1.44%) than in diploids (Diploids STD 4 ± 0.80%; HFM 4 ± 0.83%). The HFM diet gave a significant reduction in the numbers of triploid salmon with vertebral anomalies in comparison with the triploids fed the STD diet possibly as a result of differences in phosphorus bioavailability between the two diets. Overall, the

  12. Brain serotonergic activation in growth-stunted farmed salmon: adaption versus pathology

    DEFF Research Database (Denmark)

    Vindas, Marco A.; Johansen, Ida B.; Folkedal, Ole

    2016-01-01

    Signalling systems activated under stress are highly conserved, suggesting adaptive effects of their function. Pathologies arising from continued activation of such systems may represent a mismatch between evolutionary programming and current environments. Here, we use Atlantic salmon (Salmo salar...

  13. The commercial viability of any intensively cultured fish species ...

    African Journals Online (AJOL)

    spamer

    acids. It is, however, the protein in the diet that pro- vides the amino acids. Inadequate protein in the ..... nivorous species such as Atlantic salmon Salmo salar and striped bass Morone ... tailed investigations on essential fatty acid and amino.

  14. The relative roles of external and internal CO(2) versus H(+) in eliciting the cardiorespiratory responses of Salmo salar and Squalus acanthias to hypercarbia.

    Science.gov (United States)

    Perry, S F; McKendry, J E

    2001-11-01

    Fish breathing hypercarbic water encounter externally elevated P(CO(2)) and proton levels ([H(+)]) and experience an associated internal respiratory acidosis, an elevation of blood P(CO(2)) and [H(+)]. The objective of the present study was to assess the potential relative contributions of CO(2) versus H(+) in promoting the cardiorespiratory responses of dogfish (Squalus acanthias) and Atlantic salmon (Salmo salar) to hypercarbia and to evaluate the relative contributions of externally versus internally oriented receptors in dogfish. In dogfish, the preferential stimulation of externally oriented branchial chemoreceptors using bolus injections (50 ml kg(-1)) of CO(2)-enriched (4 % CO(2)) sea water into the buccal cavity caused marked cardiorespiratory responses including bradycardia (-4.1+/-0.9 min(-1)), a reduction in cardiac output (-3.2+/-0.6 ml min(-1) kg(-1)), an increase in systemic vascular resistance (+0.3+/-0.2 mmHg ml min(-1) kg(-1)), arterial hypotension (-1.6+/-0.2 mmHg) and an increase in breathing amplitude (+0.3+/-0.09 mmHg) (means +/- S.E.M., N=9-11). Similar injections of CO(2)-free sea water acidified to the corresponding pH of the hypercarbic water (pH 6.3) did not significantly affect any of the measured cardiorespiratory variables (when compared with control injections). To preferentially stimulate putative internal CO(2)/H(+) chemoreceptors, hypercarbic saline (4 % CO(2)) was injected (2 ml kg(-1)) into the caudal vein. Apart from an increase in arterial blood pressure caused by volume loading, internally injected CO(2) was without effect on any measured variable. In salmon, injection of hypercarbic water into the buccal cavity caused a bradycardia (-13.9+/-3.8 min(-1)), a decrease in cardiac output (-5.3+/-1.2 ml min(-1) kg(-1)), an increase in systemic resistance (0.33+/-0.08 mmHg ml min(-1) kg(-1)) and increases in breathing frequency (9.7+/-2.2 min(-1)) and amplitude (1.2+/-0.2 mmHg) (means +/- S.E.M., N=8-12). Apart from a small increase

  15. Comportement de l'espèce “Salmo trutta” dans le bassin de la Seine. Suite et fin

    Directory of Open Access Journals (Sweden)

    ARRIGNON J.

    1968-04-01

    — The exotic peninsular (Danish stocks gives a higher rate of migratories than the native continental stocks. — Some fishes have irregular removings, either upstream or downstream, to search a more propicious environment. — The breeders are going more or less far to search proper spawning places. — The native populations are very sedentary, if they lives in a stable and inviolate environment. — The concentrations of fishes in Low-Seine includes, vith the same silverwhite skin : — Salmo trutta fario ; — Salmo trutta gairdneri ; — and Salmo salar. But, it is not possible, to make a discrimination between Salmo trutta fario (dulcaquicola ; and Salmo trutta fario (marina. The migrator fishes of the species changes their skin at the time of the physiological motivation and it can be found all the possible links between the sea-trout and the streamtrout.

  16. Molecular mechanisms of continuous light inhibition of Atlantic salmon parr-smolt transformation

    DEFF Research Database (Denmark)

    Steffansson, Sigurd O.E.; Nielsen, Tom O.; Ebbesson, Lars O.E.

    2007-01-01

    Atlantic salmon (Salmo salar) rely on changes in photoperiod for the synchronization of the developmental events constituting the parr-smolt transformation. In the absence of photoperiod cues, parr-smolt transformation is incomplete, and such 'pseudo-smolts' normally fail to adapt to seawater. Th...

  17. Saponin-containing subfractions of soybean molasses induce enteritis in the distal intestine of Atlantic salmon

    NARCIS (Netherlands)

    Knudsen, D.; Urán, P.; Arnous, A.; Koppe, W.

    2007-01-01

    The current work aimed at tracing the causative components for soybean-induced enteritis in Atlantic salmon (Salmo salar L.). Soybean molasses was subjected to phase separation using n-butanol. Three subfractions were obtained as follows: butanol phase, precipitate, and water phase. The biochemical

  18. 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

  19. Using Linkage Maps as a Tool To Determine Patterns of Chromosome Synteny in the Genus Salvelinus

    Directory of Open Access Journals (Sweden)

    Matthew C. Hale

    2017-11-01

    Full Text Available Next generation sequencing techniques have revolutionized the collection of genome and transcriptome data from nonmodel organisms. This manuscript details the application of restriction site-associated DNA sequencing (RADseq to generate a marker-dense genetic map for Brook Trout (Salvelinus fontinalis. The consensus map was constructed from three full-sib families totaling 176 F1 individuals. The map consisted of 42 linkage groups with a total female map size of 2502.5 cM, and a total male map size of 1863.8 cM. Synteny was confirmed with Atlantic Salmon for 38 linkage groups, with Rainbow Trout for 37 linkage groups, Arctic Char for 36 linkage groups, and with a previously published Brook Trout linkage map for 39 linkage groups. Comparative mapping confirmed the presence of 8 metacentric and 34 acrocentric chromosomes in Brook Trout. Six metacentric chromosomes seem to be conserved with Arctic Char suggesting there have been at least two species-specific fusion and fission events within the genus Salvelinus. In addition, the sex marker (sdY; sexually dimorphic on the Y chromosome was mapped to Brook Trout BC35, which is homologous with Atlantic Salmon Ssa09qa, Rainbow Trout Omy25, and Arctic Char AC04q. Ultimately, this linkage map will be a useful resource for studies on the genome organization of Salvelinus, and facilitates comparisons of the Salvelinus genome with Salmo and Oncorhynchus.

  20. Infection experiments with novel Piscine orthoreovirus from rainbow trout (Oncorhynchus mykiss) in salmonids

    DEFF Research Database (Denmark)

    Hauge, Helena; Vendramin, Niccolò; Taksdal, Torunn

    2017-01-01

    A new disease in farmed rainbow trout (Onchorhyncus mykiss) was described in Norway in 2013. The disease mainly affected the heart and resembled heart and skeletal muscle inflammation (HSMI) in Atlantic salmon (Salmo salar L.). HSMI is associated with Piscine orthoreovirus (PRV), and a search...

  1. Carryover of CH3Hg from feed to sea bass and salmon

    DEFF Research Database (Denmark)

    Rasmussen, Rie Romme; Håland, Weronica; Larsen, Bodil Katrine

    toxicokinetic parameters.The study included Atlantic salmon (Salmo salar), which is one of the main farmed seafood product consumed in Europe and with production in Northen Europe as well as European seabass (Dicentrarchus labrax) produced in Southern Europe, where it is a highly consumed seafood...

  2. Effect of enriched Brachionus plicatilis and Artemia salina nauplii by ...

    African Journals Online (AJOL)

    AJL

    2012-01-05

    Jan 5, 2012 ... medium, especially the short chain fatty acids (C16:0, C18:0 and ... constituted 22.3% of the total fatty acids, due to the presence of DHA ...... to influence tissue fatty acid composition of Atlantic salmon, Salmo salar L., parr.

  3. Dicty_cDB: Contig-U04414-1 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available -1A; AltName: Full... 68 4e-10 AB241241_1( AB241241 |pid:none) Symbiotic protist ...48727 |pid:none) Salmo salar clone ssal-rgb2-626-04... 65 3e-09 AB241242_1( AB241242 |pid:none) Symbiotic

  4. Is humane slaughter of fish possible for industry?

    NARCIS (Netherlands)

    Vis, van de J.W.; Kestin, S.; Robb, D.; Oehlenschlaeger, J.; Lambooij, E.; Kuhlmann, H.; Kloosterboer, K.

    2003-01-01

    The objective was to evaluate industrial and research slaughter methods for Atlantic salmon (Salmo salar), gilt-head seabream (Sparus auratus) and eel (Anguilla anguilla) with respect to welfare and quality. As a general term of reference, an optimal slaughter method should render fish unconscious

  5. Investigation into the susceptibility of saithe Pollachius virens to infectious salmon anaemia virus (ISAV) and their potential role as a vector for viral transmission

    DEFF Research Database (Denmark)

    Snow, M.; Raynard, R.; Bruno, D.W.

    2002-01-01

    salmon Salmo salar. Despite the individual testing of 120 ISAV-exposed saithe, ISAV was not detectable using RT-PCR, the most sensitive ISAV diagnostic tool demonstrated to date. Furthermore, saithe exposed to ISAV-infected salmon were not capable of transmitting virus when transferred to tanks...

  6. Adaptation Turning Points in River Restoration? The Rhine salmon case

    NARCIS (Netherlands)

    Bölscher, T.; Slobbe, van E.J.J.; Vliet, van M.T.H.; Werners, S.E.

    2013-01-01

    Abstract: Bringing a sustainable population of Atlantic salmon (Salmo salar) back into the Rhine, after the species became extinct in the 1950s, is an important environmental ambition with efforts made both by governments and civil society. Our analysis finds a significant risk of failure of salmon

  7. On the validity of setting breakpoint minimum inhibition concentrations at one quarter of the plasma concentration achieved following oral administration of oxytetracycline

    DEFF Research Database (Denmark)

    Coyne, R.; Samuelsen, O.; Bergh, Ø.

    2004-01-01

    Plasma concentrations of oxytetracycline (OTC) were established in two Atlantic salmon (Salmo salar) pre-smolts populations after they had received OTC medicated feed at a rate of 75 mg OTC/kg over 10 days. One population was experiencing an epizootic of furunculosis in a commercial freshwater farm...

  8. The status of limnophilic fish and the need for conservation in floodplains along the lower Rhine, a large regulated river

    NARCIS (Netherlands)

    Grift, R.E.; Buijse, A.D.; Van Geest, G.J.

    2006-01-01

    Recovery of the fish community of the river Rhine focussed mainly on the return of migratory species, in particular the Atlantic Salmon, Salmo salar, and to a lesser extent on rheophilic fish species. Several limnophilic species that characterize remote parts of the floodplains are, however, also

  9. Salmonid Chromosome Evolution as Revealed by a Novel Method for Comparing RADseq Linkage Maps

    Science.gov (United States)

    Gosselin, Thierry; Normandeau, Eric; Lamothe, Manuel; Isabel, Nathalie; Audet, Céline; Bernatchez, Louis

    2016-01-01

    Whole genome duplication (WGD) can provide material for evolutionary innovation. Family Salmonidae is ideal for studying the effects of WGD as the ancestral salmonid underwent WGD relatively recently, ∼65 Ma, then rediploidized and diversified. Extensive synteny between homologous chromosome arms occurs in extant salmonids, but each species has both conserved and unique chromosome arm fusions and fissions. Assembly of large, outbred eukaryotic genomes can be difficult, but structural rearrangements within such taxa can be investigated using linkage maps. RAD sequencing provides unprecedented ability to generate high-density linkage maps for nonmodel species, but can result in low numbers of homologous markers between species due to phylogenetic distance or differences in library preparation. Here, we generate a high-density linkage map (3,826 markers) for the Salvelinus genera (Brook Charr S. fontinalis), and then identify corresponding chromosome arms among the other available salmonid high-density linkage maps, including six species of Oncorhynchus, and one species for each of Salmo, Coregonus, and the nonduplicated sister group for the salmonids, Northern Pike Esox lucius for identifying post-duplicated homeologs. To facilitate this process, we developed MapComp to identify identical and proximate (i.e. nearby) markers between linkage maps using a reference genome of a related species as an intermediate, increasing the number of comparable markers between linkage maps by 5-fold. This enabled a characterization of the most likely history of retained chromosomal rearrangements post-WGD, and several conserved chromosomal inversions. Analyses of RADseq-based linkage maps from other taxa will also benefit from MapComp, available at: https://github.com/enormandeau/mapcomp/ PMID:28173098

  10. Increased susceptibility to infectious salmon anemia virus (ISAv) in Lepeophtheirus salmonis – infected Atlantic salmon

    Science.gov (United States)

    The salmon louse and infectious salmon anemia virus (ISAv) are the two most significant pathogens of concern to the Atlantic salmon (Salmo salar) aquaculture industry. However, the interactions between sea lice and ISAv, as well as the impact of a prior sea lice infection on the susceptibility of th...

  11. Dicty_cDB: Contig-U14682-1 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available nslandica notch mRN... 39 1.4 AF533016_1( AF533016 |pid:none) Salmo salar hyperosmo.... 39 1.4 AK289553_1( AK289553 |pid:none) Homo sapiens cDNA FLJ76207 complet... 39 1.4 EU273942_1( EU273942 |pid:none) Amphimedon quee

  12. Salars evaporation rates evaluation using isotope techniques, Bellavista Salar, Chile

    International Nuclear Information System (INIS)

    Grilli, A.; Ortiz, J.

    1989-01-01

    Long term evaporation rates are evaluated in different soil conditions at Bellavista Salar, using environmental isotope profiles (oxygen-18) of the unsaturated soil zone. The Barnes and Allison model was adapted to stratified soils under non-saturation conditions and for a non-isothermal permanent regime. To apply the proposed model, field data of the different variables were used and the evaporation rates were obtained adjunting the δ 18 O values generated by the model to those experimentally measured in the water extracted from the soil profile of the unsaturated soil zone. (author). 13 refs, 8 figs

  13. Download this PDF file

    African Journals Online (AJOL)

    hakan

    Whole body fat content of the fish fed the diets containing the .... mg vitamin B6; 50 mg vitamin B12; 500 mg D-biotin; 1.200 mg folic acid; 200.000 mg; 300.000 mg inositol; 1.200.000 ..... salmon, Salmo salar L. Aquaculture 185, 299-311. Davis ...

  14. 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

  15. Evaluation of partial water reuse systems used for Atlantic salmon smolt production at the White River National Fish Hatchery

    Science.gov (United States)

    Eight of the existing 9.1 m (30 ft) diameter circular culture tanks at the White River National Fish Hatchery in Bethel, Vermont, were retrofitted and plumbed into two 8,000 L/min partial water reuse systems to help meet the region's need for Atlantic salmon (Salmo salar) smolt production. The part...

  16. Modeling the Salar de Uyuni, Bolivia as an Equipotential Surface of Earth's Gravity Field

    Science.gov (United States)

    Borsa, Adrian; Bills, Bruce

    2004-01-01

    The salar de Uyuni is a massive dry salt lake that lies at the lowest point of an internal/drainage basin in the Bolivian Altiplano. Its topography is remarkable for its extraordinary flatness over almost a full degree of latitude and longitude. We surveyed a 54 x 45 km region of the salar with kinematic GPS in September, 2002 and found a topographic range of only 80 cm over the entire surveyed area. Furthermore, the survey revealed distinct surface features with several dominant wavelengths and orientations. Some of these appear to be aligned with orographic features that intersect the salar, leading us to conjecture that they are the surface expression of high-density mountains that have been buried by low-density basin sediments. Over the oceans, a similar correspondence between basin bathymetry and surface topography is exploited to map the seafloor using sea-surface satellite altimetry measurements, with the sea surface following geoid undulations due to the underwater mass distribution. On the salar, annual flooding creates a shallow lake whose surface also lies on a equipotential surface shaped by the distribution of underlying mass. The link to the actual salar surface is via the dissolution and redeposition of salt by the lake waters, which appears to push the system to an equilibrium of constant water depth and the coincidence of the shapes of the lake surface and bottom. To test our hypothesis about the origin of the surface features on the salar, we compare our GPS survey elevations with the equipotential surface generated from local gravity measurements in conjunction with gravity and potential values from the EGM96 global geopotential model. 50% of the variance of the GPS elevations can be explained by equipotential surface undulations from the EGM96 model alone, and an additional 40% is explained by the shorter-wavelength equipotential surface derived from local gravity. We examine the unexplained 10% of elevation variance from the standpoint of

  17. Infectious salmon anaemia virus (ISAV) in Chilean Atlantic salmon (Salmo salar) aquaculture: emergence of low pathogenic ISAV-HPR0 and re-emergence of virulent ISAV-HPR∆: HPR3 and HPR14

    Science.gov (United States)

    2013-01-01

    Abstact Infectious salmon anaemia (ISA) is a serious disease of marine-farmed Atlantic salmon (Salmo salar) caused by ISA virus (ISAV), which belongs to the genus Isavirus, family Orthomyxoviridae. ISA is caused by virulent ISAV strains with deletions in a highly polymorphic region (HPR) of the hemagglutinin-esterase (HE) protein (designated virulent ISAV-HPR∆). This study shows the historic dynamics of ISAV-HPR∆ and ISAV-HPR0 in Chile, the genetic relationship among ISAV-HPR0 reported worldwide and between ISAV-HPR0 and ISAV-HPR∆ in Chile, and reports the 2013 ISA outbreak in Chile. The first ISA outbreak in Chile occurred from mid-June 2007 to 2010 and involved the virulent ISAV-HPR7b, which was then replaced by a low pathogenic ISAV-HPR0 variant. We analyzed this variant in 66 laboratory-confirmed ISAV-HPR0 cases in Chile in comparison to virulent ISAV-HPR∆ that caused two new ISA outbreaks in April 2013. Multiple alignment and phylogenetic analysis of HE sequences from all ISAV-HPR0 viruses allowed us to identify three genomic clusters, which correlated with three residue patterns of ISAV-HPR0 (360PST362, 360PAN362 and 360PAT362) in HPR. The virus responsible for the 2013 ISAV-HPR∆ cases in Chile belonged to ISAV-HPR3 and ISAV-HPR14, and in phylogenetic analyses, both clustered with the ISAV-HPR0 found in Chile. The ISAV-HPR14 had the ISAV-HPR0 residue pattern 360PAT362, which is the only type of ISAV-HPR0 variant found in Chile. This suggested to us that the 2013 ISAV-HPR∆ re-emerged from ISAV-HPR0 that is enzootic in Chilean salmon aquaculture and were not new introductions of virulent ISAV-HPR∆ to Chile. The clinical presentations and diagnostic evidence of the 2013 ISA cases indicated a mixed infection of ISAV with the ectoparasite Caligus rogercresseyi and the bacterium Piscirickettsia salmonis, which underscores the need for active ISAV surveillance in areas where ISAV-HPR0 is enzootic, to ensure early detection and control of new ISA

  18. 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).

  19. Computer vision-based evaluation of pre- and postrigor changes in size and shape of Atlantic cod (Gadus morhua) and Atlantic salmon (Salmo salar) fillets during rigor mortis and ice storage: effects of perimortem handling stress.

    Science.gov (United States)

    Misimi, E; Erikson, U; Digre, H; Skavhaug, A; Mathiassen, J R

    2008-03-01

    The present study describes the possibilities for using computer vision-based methods for the detection and monitoring of transient 2D and 3D changes in the geometry of a given product. The rigor contractions of unstressed and stressed fillets of Atlantic salmon (Salmo salar) and Atlantic cod (Gadus morhua) were used as a model system. Gradual changes in fillet shape and size (area, length, width, and roundness) were recorded for 7 and 3 d, respectively. Also, changes in fillet area and height (cross-section profiles) were tracked using a laser beam and a 3D digital camera. Another goal was to compare rigor developments of the 2 species of farmed fish, and whether perimortem stress affected the appearance of the fillets. Some significant changes in fillet size and shape were found (length, width, area, roundness, height) between unstressed and stressed fish during the course of rigor mortis as well as after ice storage (postrigor). However, the observed irreversible stress-related changes were small and would hardly mean anything for postrigor fish processors or consumers. The cod were less stressed (as defined by muscle biochemistry) than the salmon after the 2 species had been subjected to similar stress bouts. Consequently, the difference between the rigor courses of unstressed and stressed fish was more extreme in the case of salmon. However, the maximal whole fish rigor strength was judged to be about the same for both species. Moreover, the reductions in fillet area and length, as well as the increases in width, were basically of similar magnitude for both species. In fact, the increases in fillet roundness and cross-section height were larger for the cod. We conclude that the computer vision method can be used effectively for automated monitoring of changes in 2D and 3D shape and size of fish fillets during rigor mortis and ice storage. In addition, it can be used for grading of fillets according to uniformity in size and shape, as well as measurement of

  20. Differentiating the relative importance of land cover change and geomorphic processes on fine sediment sequestration in a logged watershed

    Science.gov (United States)

    Kasprak, Alan; Magilligan, Francis J.; Nislow, Keith H.; Renshaw, Carl E.; Snyder, Noah P.; Dade, W. Brian

    2013-03-01

    Timber harvest often results in accelerated soil erosion and subsequent elevated fine (winnowing these fines from the channel bed. These results further suggest that under contemporary land use conditions, the geomorphic and geologic setting represents a first-order control on channel substrate and habitat suitability for salmonid fishes, including federally endangered Atlantic salmon (Salmo salar), in coastal drainages of northeastern Maine.

  1. Geochemical evolution of brines in the Salar of Uyuni, Bolivia.

    Science.gov (United States)

    Rettig, S.L.; Jones, B.F.; Risacher, F.

    1980-01-01

    Recent analyses of brines from the Salars of Uyuni and Coipasa have been compared with published data for Lakes Titicaca and Poopo to evaluate solute compositional trends in these remnants of two large Pleistocene lakes once connected by overflow from the N to the S of the Bolivian Altiplano. From Titicaca to Poopo the water shows an increase in Cl and N somewhat greater than the total solutes. Ca and SO4 increase to a lesser extent than total dissolved solids, and carbonate species are relatively constant. Between Poopo and Coipasa proportions of Ca, SO4 and CO3 continue to decrease. At Coipasa and Uyuni, the great salars frequently evaporate to halite saturation. Halite crystallization is accompanied by an increased K, Mg and SO4 in residual brines. - from Authors

  2. Upstream Atlantic salmon (Salmo salar) passage

    International Nuclear Information System (INIS)

    Clay, C.H.

    1993-01-01

    Upstream salmon passage though a dam is discussed with respect to three main components: the fishway entrance, the fishway, and the exit. Design considerations and alternative types of components are presented. For fishway entrances, an important consideration is the positioning of the entrance as far upstream as the fish can swim with respect to obstacles. For powerhouses using water diverted from a river, the problem of leading fish past the powerhouse may be overcome by either installing a tailrace barrier or increasing the flow until the home stream odor is sufficient to attract fish. Swimming ability should be the first consideration in fishway design. Fishways with 50 cm drops per pool would be satisfactory in most cases. The problem of headwater fluctuation is overcome through careful fishway selection. Fish locks, hoists, and elevators are other alternatives to pool/weir fishways. The location for a fish exit must be decided on the basis of whether the fishway will be used only for upstream migrations. 5 refs., 1 fig., 1 tab

  3. Iron Overload Is Associated With Oxidative Stress and Nutritional Immunity During Viral Infection in Fish.

    Science.gov (United States)

    Tarifeño-Saldivia, Estefanía; Aguilar, Andrea; Contreras, David; Mercado, Luis; Morales-Lange, Byron; Márquez, Katherine; Henríquez, Adolfo; Riquelme-Vidal, Camila; Boltana, Sebastian

    2018-01-01

    Iron is a trace element, essential to support life due to its inherent ability to exchange electrons with a variety of molecules. The use of iron as a cofactor in basic metabolic pathways is essential to both pathogenic microorganisms and their hosts. During evolution, the shared requirement of micro- and macro-organisms for this important nutrient has shaped the pathogen-host relationship. Infectious pancreatic necrosis virus (IPNv) affects salmonids constituting a sanitary problem for this industry as it has an important impact on post-smolt survival. While immune modulation induced by IPNv infection has been widely characterized on Salmo salar , viral impact on iron host metabolism has not yet been elucidated. In the present work, we evaluate short-term effect of IPNv on several infected tissues from Salmo salar . We observed that IPNv displayed high tropism to headkidney, which directly correlates with a rise in oxidative stress and antiviral responses. Transcriptional profiling on headkidney showed a massive modulation of gene expression, from which biological pathways involved with iron metabolism were remarkable. Our findings suggest that IPNv infection increase oxidative stress on headkidney as a consequence of iron overload induced by a massive upregulation of genes involved in iron metabolism.

  4. Screen for Footprints of Selection during Domestication/Captive Breeding of Atlantic Salmon

    Directory of Open Access Journals (Sweden)

    Anti Vasemägi

    2012-01-01

    Full Text Available Domesticated animals provide a unique opportunity to identify genomic targets of artificial selection to the captive environment. Here, we screened three independent domesticated/captive Atlantic salmon (Salmo salar strains and their wild progenitor populations in an effort to detect potential signals of domestication selection by typing of 261 SNPs and 70 microsatellite loci. By combining information from four different neutrality tests, in total ten genomic regions showed signs of directional selection based on multiple sources of evidence. Most of the identified candidate regions were rather small ranging from zero to a few centimorgans (cM in the female Atlantic salmon linkage map. We also evaluated how adaptation from standing variation affects adjacent SNP and microsatellite variation along the chromosomes and, by using forward simulations with strong selection, we were able to generate genetic differentiation patterns comparable to the observed data. This study highlights the significance of standing genetic variation during the early stages of adaptation and represents a useful step towards identifying functional variants involved in domestication of Atlantic salmon.

  5. Fish responses (Salmo salar) after exposure to trisodiumcitrate; Fiskeresponser (Salmo salar) som foelge av eksponering av trinatriumsitrat

    Energy Technology Data Exchange (ETDEWEB)

    Kroglund, Frode

    2012-07-01

    Statkraft Development AS wants to build an osmotic power plant in Sunndalsoera, Norway. Osmotic power means that the osmotic pressure between fresh and saltwater is utilized where the two water sources are separated by a membrane. These membranes need to be washed. A few times a year washing will include use of chemicals. Trisodiumcitrate is here a relevant chemical. The toxicity of trisodiumcitrate with respect to fish is poorly documented. To bridge this knowledge gap prior to finalizing the project plans, a range-finder test was performed to identify possible adverse effects of the chemical. Trisodiumcitrate is a chelator and will bind to and create loose complexes with ions. Fish can respond negatively to the chemical in itself and/or to water quality changes caused by the chemical addition. The exposures were performed using wild salmon parr, collected by electrofishing in Storelva. Norway. Salmon is normally the most sensitive species to contaminants in Norwegian rivers. The most sensitive life stage is the smolt stage, when the fish undergo physiological changes in preparation for a marine life. Smolt is not present in fall. The use of hatchery reared fall-smolt is not recommended due to differences in size. To provide data to be used in the planning of the power plant, exposures were therefore performed using parr (1+). The wash water will be released over a four hour time span to ensure sufficient dilution. The fish were exposed for 6 days to provoke possible negative responses to the chemicals. Following dilution in the river/estuary, a nominal dose of trisodiumcitrate will be in the range of 10 mg/l. To identify concentrations that could cause negative responses, fish were exposed to a concentration gradient that was 0.1, 0.3, 3 and 10 times the nominal dose. The exposure were performed in a flow-through setup where the chemicals were added continuously to the water. No fish died during the exposure. There were no statistically of biologically significant difference in blood chemistry between the groups and the control. There was a slight tendency towards fish exposed to 30 or 100 mg trisodiumcitrate/l had reduced fright response. This change occurred first after day 4, and was subtle. Salmon is the most sensitive fish species present in Norwegian rivers. The parr stage is less sensitive than the smolt stage. The main smolt run lasts for 2 to 3 weeks in spring with around 6 weeks from start to end. The test can be repeated using smolt to verify the lack of toxicity. It should be possible to avoid discharge of wash water during the main smolt run-period. Based on this exposure, trisodiumcitrate up to 100 mg/l has no visible adverse effect on salmon parr. (Author)

  6. 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.

  7. Exterior indicators and physiological signs' indices of juveniles Salmo salar L. in the rivers of the Kola Peninsula

    Directory of Open Access Journals (Sweden)

    Anokhina V. S.

    2017-06-01

    Full Text Available The range of background values of main parameters of the exterior and indices of morphophysiological features of autumn juvenile salmon Salmon salar L. in four rivers of the Kola Peninsula not affected by hatchery production have been investigated. The importance of such studies is associated with intensification of artificial reproduction of salmon and occurrence of hatchery fish with characters different from wild individuals in the rivers. Currently hatchery reproduction of Atlantic salmon is not carried out in the European North of Russia, however, the need to choose a local salmon population for further hatchery reproduction is obvious. Accumulation of biological data on salmon in the rivers of the Kola Peninsula is important for population monitoring of wild stocks. Samples of juveniles widely varying in size have been collected by electrofishing in the Rivers Pechenga, Zapadnaya Litsa and Titovka of the Barents Sea basin, as well as in the tributaries of the River Varzuga inflowing the White Sea. For each sample individual and group indices of elongation, girth and massiveness have been calculated. The physiological state of the fish has been assessed with allowance for the fatness factor (according to Clark and indices of internal organs. It has been found that in the autumn season (September the average statistical values of the morphological indices characterizing the appearance of the fry from four rivers differ with a high degree of reliability. Individual fluctuations in morphological parameters are in the range of values: elongation – from 311 to 725 %; girth – from 41 to 85 %; massiveness – from 150 to 530 %. The mean values of morphophysiological indices for each of the four river populations have been presented. The obtained values of the studied parameters of juveniles of Atlantic salmon can be used for subsequent monitoring of populations.

  8. Genetic differentiation and forensic efficiency evaluation for Chinese Salar ethnic minority based on a 5-dye multiplex insertion and deletion panel.

    Science.gov (United States)

    Ma, Ruilin; Shen, Chunmei; Wei, Yuanyuan; Jin, Xiaoye; Guo, Yuxin; Mu, Yuling; Sun, Siqi; Chen, Chong; Cui, Wei; Wei, Zhaoming; Lian, Zhenmin

    2018-06-20

    The present study investigated the genetic diversities of 30 autosomal insertion and deletion (InDel) loci of Investigator DIPplex kit (Qiagen) in Chinese Salar ethnic minority and explored the genetic relationships between the studied Salar group and other populations. The allelic frequencies of deletion alleles at the 30 InDel loci were in the range of 0.1739 (HLD64) to 0.8478 (HLD39). The discrimination power, polymorphism information content and probability of exclusion ranged from 0.4101 (HLD39) to 0.6447 (HLD136), 0.2247 (HLD39) to 0.3750 (HLD92) and 0.0400 (HLD39) to 0.2806 (HLD92), respectively. The observed and expected heterozygosity were in the range of 0.2348 (HLD39) to 0.5913 (HLD92), and 0.2580 (HLD39) to 0.5000 (HLD92), respectively. The cumulative discrimination power and probability of exclusion of the 30 loci reached 0.999999999993418 and 0.99039, respectively. The results of population genetic differentiation comparisons revealed that Salar group had similar allele distributions with Qinghai Tibetan, Xibe and Yi groups. Population Bayesian cluster analysis showed that there were similar ancestry components between Salar group and most Chinese populations. Besides, the principal components analysis and phylogenetic reconstructions further indicated that Salar group had intimate genetic relationships with Qinghai Tibetan and Xibe groups. In short, the results of the current studies indicated the genetic distributions of the 30 InDel loci in Salar group were relatively high genetic polymorphisms, which could be used in forensic individual identifications and as a supplementary tool for complex paternity testing. Copyright © 2018 Elsevier B.V. All rights reserved.

  9. Functional characterization and localization of a gill-specific claudin isoform in Atlantic salmon

    DEFF Research Database (Denmark)

    Engelund, Morten Buch; Yu, Alan S L; Li, Jiahua

    2012-01-01

    Claudins are the major determinants of paracellular epithelial permeability in multicellular organisms. In Atlantic salmon (Salmo salar L.), we previously found that mRNA expression of the abundant gill-specific claudin 30 decreases during seawater (SW) acclimation, suggesting that this claudin i...... that claudin 30 functions as a cation barrier between pavement cells in the gill and also has a general role in cell-cell adhesion in deeper layers of the epithelium....

  10. Biologic Effects of Electric and Magnetic Fields Associated with Proposed Project Seafarer

    Science.gov (United States)

    1977-01-01

    antenna operation, and careful studies by radar tracking should be continued using available ELF sources, such as the Wisconsin ’ Pest Facility. It...human triqlyceride concentrations. 3 In another study, Beischer and Brehl used 140 8-week-old virgin female white mice; 70 mice were exposed for 24 h to...conducted by McCleave et al., possible effects of the pro- posed Seafarer system on American eels (Anguilla rostrata) and Atlantic salmon (Salmo salar

  11. Influence of depth, time and human activity on detection rate of acoustic tags: a case study on two fish farms.

    Science.gov (United States)

    Otterå, H; Skilbrei, O T

    2016-03-01

    The detection rates of stationary acoustic transmitters deployed at three depths on two Atlantic salmon Salmo salar cage farms for c. 2 months were investigated. Deployment depth, time of day, day of the year and specific incidences at the farm substantially affected the rate of signal detection by the receiver. © 2016 The Authors. Journal of Fish Biology published by John Wiley & Sons Ltd on behalf of The Fisheries Society of the British Isles.

  12. Larval developmental rate, metabolic rate and future growth performance in Atlantic salmon

    DEFF Research Database (Denmark)

    Serrano, Jonathan Vaz; Åberg, Madelene; Gjoen, Hans Magnus

    2009-01-01

    , quantified as time to first feeding, and growth in later stages was demonstrated in Atlantic salmon (Salmo salar L.). The observed relationship between future growth and larval developmental rate suggests that sorting larvae by time to first feeding can be a potential tool to optimize feeding strategies...... and growth in commercial rearing of Atlantic salmon. Furthermore, the link between larval standard metabolic rate and developmental rate and future growth is discussed in the present study....

  13. When to conduct probabilistic linkage vs. deterministic linkage? A simulation study.

    Science.gov (United States)

    Zhu, Ying; Matsuyama, Yutaka; Ohashi, Yasuo; Setoguchi, Soko

    2015-08-01

    When unique identifiers are unavailable, successful record linkage depends greatly on data quality and types of variables available. While probabilistic linkage theoretically captures more true matches than deterministic linkage by allowing imperfection in identifiers, studies have shown inconclusive results likely due to variations in data quality, implementation of linkage methodology and validation method. The simulation study aimed to understand data characteristics that affect the performance of probabilistic vs. deterministic linkage. We created ninety-six scenarios that represent real-life situations using non-unique identifiers. We systematically introduced a range of discriminative power, rate of missing and error, and file size to increase linkage patterns and difficulties. We assessed the performance difference of linkage methods using standard validity measures and computation time. Across scenarios, deterministic linkage showed advantage in PPV while probabilistic linkage showed advantage in sensitivity. Probabilistic linkage uniformly outperformed deterministic linkage as the former generated linkages with better trade-off between sensitivity and PPV regardless of data quality. However, with low rate of missing and error in data, deterministic linkage performed not significantly worse. The implementation of deterministic linkage in SAS took less than 1min, and probabilistic linkage took 2min to 2h depending on file size. Our simulation study demonstrated that the intrinsic rate of missing and error of linkage variables was key to choosing between linkage methods. In general, probabilistic linkage was a better choice, but for exceptionally good quality data (<5% error), deterministic linkage was a more resource efficient choice. Copyright © 2015 Elsevier Inc. All rights reserved.

  14. Microhabitat preference of Anisakis simplex in 3 salmonid species: Immunological Implications

    DEFF Research Database (Denmark)

    Bahlool, Qusay Zuhair Mohammad; Buchmann, Kurt

    Third stage larvae of Anisakis simplex nematodes are considered to have a low host-specificity and are able to infect a wide range of fish species. However, the physiological and immunological status of the fish species may affect the fate of the worm following infection. We selected three...... different salmonid species to investigate the in vivo behavioural difference of experimentally inoculated Anisakis parasite inside these fishes. Rainbow trout (Oncorhynchus mykiss), Baltic salmon (Salmo salar) and brown trout (Salmo trutta) were used in this experiment. Infection success differed between...... species. Baltic salmon showed a higher number of nematodes successfully established, whereas brown trout and rainbow trout showed a higher natural resistance. Microhabitat results were also different according to the fish species. Anisakis simplex found in brown trout where attached to the digestive tract...

  15. Optimal size at seaward migration in an anadromous salmonid

    OpenAIRE

    Jonsson, Bror; Jonsson, Marius; Jonsson, Nina

    2016-01-01

    In this study, the probabilistic reaction norm was calculated for length at different ages of smolting before seaward migration of Atlantic salmon Salmo salar spawning in the Norwegian River Imsa. The reaction norm was compared with the optimal length at smolting estimated as the product of survival and female fecundity on the return, given their length at smolting. Logistic regression analysis on pre-migratory and migratory fish was used to estimate the probabilistic reaction norm. Length at...

  16. Salar de Surire un ecosistema altoandino en peligro, frente a escenario del cambio climático

    Directory of Open Access Journals (Sweden)

    Ingrid Garcés

    2011-12-01

    Full Text Available Este trabajo realiza un análisis al salar de Surire desde el punto de vista de la biodiversidad y sus implicancias producto del cambio climático. Como resultado se predice que los próximos años serán secos y la temperatura podría ir en aumento, lo cual afectará notablemente a la flora y fauna del altiplano. El salar de Surire es un cuerpo salino ubicado en el altiplano andino chileno, en un entorno geológico de características volcánicas. La climatología actual de aridez no permite una acumulación de agua superficial de gran extensión, y por lo tanto es posible diferenciar tres tipos principales de aguas: los aportes de drenaje, las acumulaciones de agua en la aureola pantanosa externa o “bofedales”, y las aguas del interior del cuerpo salino (surgencias termales y salmueras. Estas condiciones hidrológicas afectan factores abióticos, como anaerobiosis de suelos, disposición de nutrientes y salinidad, factores determinantes del desarrollo de la flora y fauna. Palabras claves: Salar de Surire; Biodiversidad andina; Cambio climático; Ecosistema andino

  17. Modeling the topography of the salar de Uyuni, Bolivia as an equipotential surface of Earth’s gravity field

    OpenAIRE

    Borsa, Adrian

    2008-01-01

    The salar de Uyuni is a massive dry salt lake that lies at the lowest point of an internal drainage basin in the Bolivian Altiplano. A kinematic GPS survey of the salar in September 2002 found a topographic range of only 80 cm over a 54 × 45 km area and subtle surface features that appeared to correlate with mapped gravity. In order to confirm the correlation between topography and gravity/geopotential, we use local gravity measurements and the EGM96 global geopotential model to construct a c...

  18. The genetic architecture of growth and fillet traits in farmed Atlantic salmon (Salmo salar).

    Science.gov (United States)

    Tsai, Hsin Yuan; Hamilton, Alastair; Guy, Derrick R; Tinch, Alan E; Bishop, Stephen C; Houston, Ross D

    2015-05-19

    Performance and quality traits such as harvest weight, fillet weight and flesh color are of economic importance to the Atlantic salmon aquaculture industry. The genetic factors underlying these traits are of scientific and commercial interest. However, such traits are typically polygenic in nature, with the number and size of QTL likely to vary between studies and populations. The aim of this study was to investigate the genetic basis of several growth and fillet traits measured at harvest in a large farmed salmon population by using SNP markers. Due to the marked heterochiasmy in salmonids, an efficient two-stage mapping approach was applied whereby QTL were detected using a sire-based linkage analysis, a sparse SNP marker map and exploiting low rates of recombination, while a subsequent dam-based analysis focused on the significant chromosomes with a denser map to confirm QTL and estimate their position. The harvest traits all showed significant heritability, ranging from 0.05 for fillet yield up to 0.53 for the weight traits. In the sire-based analysis, 1695 offspring with trait records and their 20 sires were successfully genotyped for the SNPs on the sparse map. Chromosomes 13, 18, 19 and 20 were shown to harbor genome-wide significant QTL affecting several growth-related traits. The QTL on chr. 13, 18 and 20 were detected in the dam-based analysis using 512 offspring from 10 dams and explained approximately 6-7 % of the within-family variation in these traits. We have detected several QTL affecting economically important complex traits in a commercial salmon population. Overall, the results suggest that the traits are relatively polygenic and that QTL tend to be pleiotropic (affecting the weight of several components of the harvested fish). Comparison of QTL regions across studies suggests that harvest trait QTL tend to be relatively population-specific. Therefore, the application of marker or genomic selection for improvement in these traits is likely to be

  19. Pressure shock triploidization of Salmo trutta f. lacustris and Salvelinus umbla eggs and its impact on fish development.

    Science.gov (United States)

    Lahnsteiner, Franz; Kletzl, Manfred

    2018-07-15

    The study tested the efficiency of hydrostatic pressure triploidization methods for Salmo trutta f. lacustris and Salvelinus umbla and investigated the effects on survival rate, skeletal malformation, and on morphometrics and cellular composition of gills, spleen, liver, kidney, intestine, and blood. In Salmo trutta f. lacustris a 100% triploidy rate in combination with high larvae survival rate (80% in comparison to control) was obtained when treating eggs with a pressure of 66 × 10 3  kPa 360 °C temperature minutes (CTM) post fertilization for 5 min, in Salvelinus umbla with a similar pressure after 270 CTM. Juvenile triploid Salmo trutta f. lacustris and Salvelinus umbla (145 days post hatch) had neither an increased rate of mortality, nor an increased rate of malformations. In triploid Salmo trutta f. lacustris and Salvelinus umbla the erythrocyte volume was 50% higher and the erythrocyte concentration in peripheral blood 25-35% lower relative to diploids. In triploids also the erythrocytes surface area: volume ratio was reduced. Gills of triploid Salmo trutta f. lacustris and Salvelinus umbla had increased width of primary lamellae and increased length of secondary lamellae which might compensate for unfavorable erythrocytes surface area: volume ratio. Length of the digestive tract and histology of kidney, liver, spleen, and gills were only investigated in Salmo trutta f. lacustris. In triploids the hematopoietic tissue of the kidney was decreased by 12%, the spleen index by 53%, and the erythroblast concentrations of the spleen by 42% relative to diploids, possibly indicating reduced erythropoiesis. Length of the digestive tract and cellular arrangement of intestine, liver, and gills were not affected. In summary, the used triploidization procedure seems a reliable method not counteracting the principles of animal welfare. Copyright © 2018 Elsevier Inc. All rights reserved.

  20. Morphological differences in the skin of marble trout Salmo marmoratus and of brown trout Salmo trutta

    Directory of Open Access Journals (Sweden)

    Urška Sivka

    2012-07-01

    Full Text Available Despite being genetically very closely related, the marble trout Salmo marmoratus and the brown trout Salmo trutta exhibit marked phenotypic differences, particularly with regard to skin pigmentation. Histological analysis of skin from the head and gill cover of differently aged individuals of the two species was carried out in order to characterize differences in skin structure. The basic structure of skin of the individuals studied corresponded with that described for other salmonids, though the head epidermis was somewhat thicker in S. marmoratus than in S. trutta, thickening with age in both species. Numerous secretory goblet cells and sporadic secretory sacciform cells were observed in the upper and middle part of the epidermis in both species. Melanophores were present in both species only in the dermis, and were bigger in S. marmoratus and present at lower average density than in S. trutta, and more or less constant across all age classes. In adult S. marmoratus with fully established marble pigmentation, light areas at low density with small (i.e. aggregated melanophores were present, while in S. trutta melanophores were more uniformly distributed.

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

    Directory of Open Access Journals (Sweden)

    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

  2. Genetic differences in physiology, growth hormone levels and migratory behaviour of Atlantic salmon smolts

    DEFF Research Database (Denmark)

    Nielsen, Christian; Holdensgaard, Gert; Petersen, Hans Christian

    2001-01-01

    Out of five strains of Atlantic salmon Salmo salar of 1 + years released upstream of a fyke net in the River Gudenaa in 1996 three Lagan Atran and Corrib migrated immediately 50% of the recaptured fish reaching the net in 3-6 days. Burrishoole and Conon fish migrated with a 15-19 day delay. Smolt......+.K+-ATPase and seawater tolerance development. The study gives evidence of genetic influence on the timing and intensity of smolting and subsequent migration in Atlantic salmon....

  3. Probabilistic record linkage.

    Science.gov (United States)

    Sayers, Adrian; Ben-Shlomo, Yoav; Blom, Ashley W; Steele, Fiona

    2016-06-01

    Studies involving the use of probabilistic record linkage are becoming increasingly common. However, the methods underpinning probabilistic record linkage are not widely taught or understood, and therefore these studies can appear to be a 'black box' research tool. In this article, we aim to describe the process of probabilistic record linkage through a simple exemplar. We first introduce the concept of deterministic linkage and contrast this with probabilistic linkage. We illustrate each step of the process using a simple exemplar and describe the data structure required to perform a probabilistic linkage. We describe the process of calculating and interpreting matched weights and how to convert matched weights into posterior probabilities of a match using Bayes theorem. We conclude this article with a brief discussion of some of the computational demands of record linkage, how you might assess the quality of your linkage algorithm, and how epidemiologists can maximize the value of their record-linked research using robust record linkage methods. © The Author 2015; Published by Oxford University Press on behalf of the International Epidemiological Association.

  4. Overwintering of sea trout (Salmo trutta) in freshwater

    DEFF Research Database (Denmark)

    Thomsen, Dennis; Koed, Anders; Nielsen, Christian

    2007-01-01

    Brown trout (Salmo trutta) show large phenotypic plasticity. Juveniles may reside in their native freshwater habitat until maturation or migrate into the ocean as 1- to 3-year-old smolts. Sea-going fish (sea trout) reside at sea for 2-3 years until migrating back to their native stream for reprod......Brown trout (Salmo trutta) show large phenotypic plasticity. Juveniles may reside in their native freshwater habitat until maturation or migrate into the ocean as 1- to 3-year-old smolts. Sea-going fish (sea trout) reside at sea for 2-3 years until migrating back to their native stream...... for reproduction. However, immature fish may leave the ocean during their first or second winter at sea and overwinter in freshwater. The question is why does this occur? We tested the hypothesis that hypo-osmoregulatory capacity is compromised by low temperature in two coastal sea trout populations, one...... representing high salinity and the other, low salinity. Immature sea-run trout were caught in lower parts of two rivers during winter and acclimated to laboratory conditions. Subgroups were challenged with high salinity or low water temperature or both, and their osmoregulatory performance was investigated...

  5. Genomic arrangement of salinity tolerance QTLs in salmonids: A comparative analysis of Atlantic salmon (Salmo salar with Arctic charr (Salvelinus alpinus and rainbow trout (Oncorhynchus mykiss

    Directory of Open Access Journals (Sweden)

    Norman Joseph D

    2012-08-01

    Full Text Available Abstract Background Quantitative trait locus (QTL studies show that variation in salinity tolerance in Arctic charr and rainbow trout has a genetic basis, even though both these species have low to moderate salinity tolerance capacities. QTL were observed to localize to homologous linkage group segments within putative chromosomal regions possessing multiple candidate genes. We compared salinity tolerance QTL in rainbow trout and Arctic charr to those detected in a higher salinity tolerant species, Atlantic salmon. The highly derived karyotype of Atlantic salmon allows for the assessment of whether disparity in salinity tolerance in salmonids is associated with differences in genetic architecture. To facilitate these comparisons, we examined the genomic synteny patterns of key candidate genes in the other model teleost fishes that have experienced three whole-genome duplication (3R events which preceded a fourth (4R whole genome duplication event common to all salmonid species. Results Nine linkage groups contained chromosome-wide significant QTL (AS-2, -4p, -4q, -5, -9, -12p, -12q, -14q -17q, -22, and −23, while a single genome-wide significant QTL was located on AS-4q. Salmonid genomes shared the greatest marker homology with the genome of three-spined stickleback. All linkage group arms in Atlantic salmon were syntenic with at least one stickleback chromosome, while 18 arms had multiple affinities. Arm fusions in Atlantic salmon were often between multiple regions bearing salinity tolerance QTL. Nine linkage groups in Arctic charr and six linkage group arms in rainbow trout currently have no synteny alignments with stickleback chromosomes, while eight rainbow trout linkage group arms were syntenic with multiple stickleback chromosomes. Rearrangements in the stickleback lineage involving fusions of ancestral arm segments could account for the 21 chromosome pairs observed in the stickleback karyotype. Conclusions Salinity tolerance in

  6. Testing of an acoustic smolt deflection system, Blantyre hydroelectric power scheme

    International Nuclear Information System (INIS)

    1996-01-01

    The aim of this study was to test the effectiveness of an underwater acoustic barrier as a means of preventing the entry of salmon (Salmo salar) and sea trout (Salmo trutta) smolts and other fish into the water intake of a hydro-electric power (HEP) station. A secondary objective was to measure the injury rate of fish passed through the turbine, so that the risk to any fish that penetrated the acoustic barrier could also be determined. The test site, which was a 575kW Kaplan plant located at Blantyre on the R. Clyde, Lanarkshire, was selected as being representative of run-of-river sites currently being developed under the Government's NFFO (Non-Fossil Fuel Obligation) and SRO (Scottish Renewables Order) schemes. A further objective was to disseminate information arising from the project to the scientific and HEP community. (author)

  7. Effect of fish and oil nature on frying process and nutritional product quality

    OpenAIRE

    Ansorena, D. (Diana); Guembe, A. (Ainhoa); Mendizabal, T. (Tatiana); Astiasarán, I. (Iciar)

    2010-01-01

    The modifications on a lean fish (cod-Gadus morhua) and a fatty fish (farmed salmon-Salmo salar) after the application of pan-frying using 2 types of oil with different lipid profile (extra virgin olive oil and sunflower oil) was the aim of this study. Fat content and total energetic value increased significantly after the frying process only in the lean fish, without relevant changes in the fatty fish. Extra virgin olive oil led to a higher fat absorption rate than sunflower oil in both fish...

  8. The effect of stress and exercise on post-mortem biochemistry of Atlantic salmon and rainbow trout

    DEFF Research Database (Denmark)

    Thomas, P.M.; Pankhurst, N.W.; Bremner, Allan

    1999-01-01

    Freshwater Atlantic salmon Salmo salar and rainbow trout Oncorhynchus mykiss responded similarly to increase in water flow (exercise), reduction in holding tank water level (stress), or 30 min chasing with water level reduction (stress and exercise). Stress generally resulted in elevated plasma c...... and exercise, results in mostly transient changes in post-mortem muscle biochemistry. These changes lead to an earlier onset and resolution of rigor, and lower post-mortem muscle pH in comparison to the control. (C) 1999 The Fisheries Society of the British Isles...

  9. Subsidiary Linkage Patterns

    DEFF Research Database (Denmark)

    Andersson, Ulf; Perri, Alessandra; Nell, Phillip C.

    2012-01-01

    channels for spillovers to competitors. We find a curvilinear relationship between the extent of competitive pressure and the quality of a subsidiary's set of local linkages. Furthermore, the extent to which a subsidiary possesses capabilities moderates this relationship: Very capable subsidiaries...... in strongly competitive environments tend to shy away from high quality linkages. We discuss our findings in light of the literature on spillovers and inter-organizational linkages.......This paper investigates the pattern of subsidiaries' local vertical linkages under varying levels of competition and subsidiary capabilities. Contrary to most previous literature, we explicitly account for the double role of such linkages as conduits of learning prospects as well as potential...

  10. The complete mitogenome of brown trout (Salmo trutta fario) and its phylogeny.

    Science.gov (United States)

    Sahoo, Prabhati K; Singh, Lalit; Sharma, Lata; Kumar, Rohit; Singh, Vijay K; Ali, S; Singh, Atul K; Barat, Ashoktaru

    2016-11-01

    The complete mitochondrial genome of Salmo trutta fario, commonly known as brown trout, was sequenced using NGS technology. The mitochondrial genome size was determined to be 16 677 bp and composed of 13 protein-coding gene (PCG), 22 tRNAs, 2 rRNA genes, and 1 putative control region. The overall mitogenome composition of S. trutta fario is A: 28.13%, G: 16.44%, C: 29.47%, and T: 25.96% with A + T content of 54.09% and G + C content of 45.91%. The gene arrangement and the order are similar to other vertebrates. The phylogenetic tree constructed using 42 complete mitogenomes of Salmonidae fishes confirmed the position of the present species under the genus Salmo of subfamily Salmoninae. NGS platform was proved to be a rapid and time-saving technology to reveal complete mitogenomes.

  11. Étude du comportement du saumon atlantique (Salmo salar L. au niveau de l'aménagement hydroélectrique de Baigts (gave de Pau lors de sa migration anadrome.

    Directory of Open Access Journals (Sweden)

    CHANSEAU M.

    1999-04-01

    Full Text Available Le comportement de 19 saumons adultes (Salmo salar L. a été étudié au niveau de l'aménagement hydroélectrique de Baigts à l'aide de la technique de radiotélémétrie lors de trois expérimentations menées en été et en automne de 1995 à 1997. La majorité des poissons a stationné bien à l'aval de l'obstacle au cours de leur blocage. Les durées de présence en continu sur le site et les départs à l'aval étaient généralement inférieurs à 1 heure, les poissons se repliant au maximum à 200-300 m à l'aval de l'ouvrage avant de se présenter de nouveau sur le site. Lors de replis de durées plus importantes, généralement supérieures à 6 heures, les poissons stationnaient principalement dans un profond s'étendant de 500 m à 1,2 kilomètre de l'obstacle. Les départs du site se produisaient plutôt au crépuscule et les retours au pied de l'obstacle préférentiellement à l'aube, révélant une rythmicité comportementale des poissons au cours du nycthémère. Les températures moyennes journalières de l'eau et les débits turbines au niveau de l'usine ont eu une influence sur les présences des poissons au niveau de l'obstacle. Les saumons se présentaient plus souvent mais stationnaient moins longuement au pied de l'aménagement lorsque les températures étaient supérieures à 16°C. Les présences des poissons dans le canal de fuite étaient nettement réduites pour des températures supérieures à 20°C tandis que le stationnement au pied du barrage était plus important pour un fonctionnement réduit (débits turbines inférieurs à 50 m3/s de l'usine. Les études ont mis en évidence l'impact important de l'aménagement sur la migration anadrome des saumons, en regard notamment des durées de blocage importantes induites par l'aménagement (jusqu'à 137 jours et du faible nombre de poissons (34 % qui a réussi à passer à l'amont. L'emplacement de l'entrée du dispositif de franchissement, situé pourtant à l

  12. Marine migration and habitat use of anadromous brown trout Salmo trutta

    DEFF Research Database (Denmark)

    Eldøy, Sindre Håvarstein; Davidsen, Jan Grimsrud; Thorstad, Eva Bonsak

    2015-01-01

    The biology and ecology of anadromous brown trout (Salmo trutta) at sea is poorly understood. This study provided information on spatial and temporal distribution of sea trout in the ocean. The behaviour of 115 individuals (veteran migrants, 270–700 mm) was tracked by using acoustic telemetry...

  13. Digest: Demographic inferences accounting for selection at linked sites†.

    Science.gov (United States)

    Simon, Alexis; Duranton, Maud

    2018-05-16

    Complex demography and selection at linked sites can generate spurious signatures of divergent selection. Unfortunately, many attempts at demographic inference consider overly simple models and neglect the effect of selection at linked sites. In this issue, Rougemont and Bernatchez (2018) applied an approximate Bayesian computation (ABC) framework that accounts for indirect selection to reveal a complex history of secondary contacts in Atlantic salmon (Salmo salar) that might explain a high rate of latitudinal clines in this species. © 2018 The Author(s). Evolution © 2018 The Society for the Study of Evolution.

  14. Omission of expected reward sensitizes the brain dopaminergic system of classically conditioned Atlantic salmon

    DEFF Research Database (Denmark)

    Vindas, M.A.; Höglund, Erik; Folkedal, O.

    in fishes. Here we show that the omission of expected reward (OER) leads to increased aggression towards conspecifics in classically conditioned Atlantic salmon (Salmo salar). Furthermore, in response to an acute stressor, OER fish displayed increased dopaminergic (DA) neurotransmission compared to controls....... There was also a general downregulation of dopamine receptor D1 gene expression in the telencephalon of OER groups, which suggests a coping mechanism in response to unbalanced DA metabolism. These results indicate that animals subjected to unpredictable reward conditions develop a senzitation of the DA...

  15. 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.

  16. Implantation of cocoa butter reduces egg and hatchling size in Salmo trutta

    NARCIS (Netherlands)

    Hoogenboom, M. O.; Armstrong, J. D.; Miles, M. S.; Burton, T.; Groothuis, T. G. G.; Metcalfe, N. B.

    This study demonstrated that, irrespective of hormone type or dose, administering cocoa butter implants during egg development affected the growth of female brown trout Salmo trutta and reduced the size of their offspring. Cortisol treatment also increased adult mortality. Caution is urged in the

  17. An environmental DNA marker for detecting nonnative brown trout (Salmo trutta)

    Science.gov (United States)

    K. J. Carim; T. M. Wilcox; M. Anderson; D. Lawrence; Michael Young; Kevin McKelvey; Michael Schwartz

    2016-01-01

    Brown trout (Salmo trutta) are widely introduced in western North America where their presence has led to declines of several native species. To assist conservation efforts aimed at early detection and eradication of this species, we developed a quantitative PCR marker to detect the presence of brown trout DNA in environmental samples. The marker strongly...

  18. Bursts and horizontal evolution of DNA transposons in the speciation of pseudotetraploid salmonids

    Directory of Open Access Journals (Sweden)

    Davidson William S

    2007-11-01

    Full Text Available Abstract Background Several genome duplications have occurred in the evolutionary history of teleost fish. In returning to a stable diploid state, the polyploid genome reorganized, and large portions are lost, while the fish lines evolved to numerous species. Large scale transposon movement has been postulated to play an important role in the genome reorganization process. We analyzed the DNA sequence of several large loci in Salmo salar and other species for the presence of DNA transposon families. Results We have identified bursts of activity of 14 families of DNA transposons (12 Tc1-like and 2 piggyBac-like families, including 11 novel ones in genome sequences of Salmo salar. Several of these families have similar sequences in a number of closely and distantly related fish, lamprey, and frog species as well as in the parasite Schistosoma japonicum. Analysis of sequence similarities between copies within the families of these bursts demonstrates several waves of transposition activities coinciding with salmonid species divergence. Tc1-like families show a master gene-like copying process, illustrated by extensive but short burst of copying activity, while the piggyBac-like families show a more random copying pattern. Recent families may include copies with an open reading frame for an active transposase enzyme. Conclusion We have identified defined bursts of transposon activity that make use of master-slave and random mechanisms. The bursts occur well after hypothesized polyploidy events and coincide with speciation events. Parasite-mediated lateral transfer of transposons are implicated.

  19. Occurrence of mislabelling in prepared fishery products in Southern Italy

    Directory of Open Access Journals (Sweden)

    Giuseppina Tantillo

    2015-09-01

    Full Text Available Fish authentication is a major concern not only for the prevention of commercial fraud, but also for the assessment of safety risks deriving from the undeclared introduction of potentially dangerous toxic or allergenic substances or environmentally damaging fish where endangered species are involved. Moreover, food authentication might affect the diet of certain groups of consumers, such as followers of religious practices. Considering the authentication of fish products is one of the key issues in food safety, quality and sustainability, the aim of this work was to investigate the prevalence of mislabelling in sole (Solea solea, plaice (Pleuronectes platessa, Atlantic salmon (Salmo salar, and hake (Merluccius merluccius fillets from markets and supermarkets located in Apulia (Southern Italy using DNA barcoding. The results of the molecular investigations reveal that 42/98 (42.8% fillet samples were not correctly labelled. In particular, 12/27 (44.4% fillets of sole (Solea solea were identified as belonging to Solea senegalensis. In addition, 13/28 (46.4% plaice (Pleuronectes platessa samples were identified as Pangasius hypophtalmus. All Atlantic salmon (Salmo salar samples were correctly labelled. Post-sequencing data analysis revealed that 17/30 (56.6% hake fillets (Merluccius merluccius were not correctly labelled, of which 8/30 samples identified as Merluccius hubbsi, 5/30 samples as Merluccius products and 4/30 as Merluccius capensis. The study reveals a high occurrence of species mislabelling in the prepared fish fillet products, further evidence of the need for increased traceability and assessment of the authenticity of food products.

  20. Field trials in Norway with SLICE (0.2% emamectin benzoate) for the oral treatment of sea lice infestation in farmed Atlantic salmon Salmo salar.

    Science.gov (United States)

    Ramstad, A; Colquhoun, D J; Nordmo, R; Sutherland, I H; Simmons, R

    2002-06-21

    Four commercial salmon farms on the West coast of Norway were recruited to a programme of field trials in which the efficacy of SLICE (0.2% emamectin benzoate; Schering-Plough Animal Health) was compared with a commercially available product, EKTOBANN (teflubenzuron 2 g kg(-1); Skretting A/S) in treating natural sea lice Lepeophtheirus salmonis infections in Atlantic salmon Salmo salmar L. At each test site, 3 fish pens were treated with each product. In total, nearly 1.2 million first-year-class fish were included in the trial, of which approximately 561,000 received emamectin benzoate at a dosage of 50 microg kg(-1) body wt d(-1), while approximately 610,000 received teflubenzuron at a dosage of 10 mg kg(-1) body wt d(-1). Medicated feed was provided at 0.5% body wt d(-1) over 7 consecutive days. Feed containing emamectin benzoate was generally well accepted by the fish and no problems were encountered in feeding the medicated diet at the desired dose. Lice numbers were counted 2 d before and 1, 7, 14 and 21 d after commencement of treatment. While treatment with both substances rapidly reduced lice numbers, pens treated with emamectin benzoate were found to harbour significantly fewer lice 14 and 21 d post-treatment. Twenty-one days following treatment with emamectin benzoate the lice abundance was reduced on average by 94%. Limited sampling outside the main study period indicated that emamectin benzoate protects against sea-lice infestation over longer periods.

  1. Guía de buenas prácticas para la gestión de escapes en la acuicultura marina. Vol II. Mitigación

    OpenAIRE

    Izquierdo-Gomez, David; Fernandez-Jover, Damian; Sanchez-Jerez, Pablo; Toledo-Guedes, Kilian; Arechavala-Lopez, Pablo; Forcada, Aitor; Valle-Pérez, Carlos

    2014-01-01

    Desde que el cultivo a gran escala de salmón (Salmo salar) en mar abierto comenzó́ en Noruega en el último tercio del siglo pasado, los escapes siempre han supuesto uno de los mayores problemas, tanto para las empresas como para el ecosistema marino. Siendo, en todos los casos, las pérdidas por escapes uno de los principales desafíos en el proceso de producción. Desde un punto de vista medioambiental, una vez que los peces escapan de las jaulas se convierten en un elemento más del ecosistema ...

  2. [Differential expression of DTSsa4 Tc1-like transposons in closely related populations of Baikal ciscoes].

    Science.gov (United States)

    Bychenko, O S; Sukhanova, L V; Azhikina, T L; Sverdlov, E D

    2009-01-01

    Two representatives of Baikal ciscoes - lake cisco and omul - diverged from a common ancestor as recently as 10-20 thousand years ago. We have found an increasing expression level of DTSsa4 Tc1-like DNA transposons in cisco and omul brains. The mapping of the sequences of these transposons from Salmo salar and Danio rerio genomes has shown that in some cases, these transposons are located in the 5' and 3' regions, as well as in the promoter regions of various genes. Probably, Tc1-like transposons affect the activity of neighboring genes, providing the adaptive divergence of the cisco population.

  3. Management measures and fishers’ commitment towards sustainable exploitation: a case study of Atlantic salmon fisheries in the Baltic Sea

    DEFF Research Database (Denmark)

    Haapasaari, Päivi Elisabet; Michielsens, Catherina C.G.J.; Karjalainen, Timo P.

    2007-01-01

    management measures on the stocks. Based on interviews and a questionnaire, we use a Bayesian belief network to examine which factors determine fishers’ commitment to sustainable fisheries goals, what impact commitment has on exploitation rate, and what measures can be taken to improve commitment. In addition...... of Atlantic salmon (Salmo salar) stocks. The results indicate that the more fishers rely on fishing as their source of income, the less is their commitment and the smaller is the impact of changes in commitment on subsequent catches. The results suggest that commitment can be improved by selecting management...

  4. A pantograph linkage

    International Nuclear Information System (INIS)

    Cole, G.V.

    1982-01-01

    A pantograph linkage is actuated by two linear actuators, pivotally connected together at the linkage. The displacement of the actuators is monitored by rectilinear potentiometers to provide feedback signals to a microprocessor which also receives input signals related to a required movement of a slave end of the linkage. In response to these signals, the microprocessor provides signals to control the displacement of the linear actuators to effect the required movement of the slave end. The movement of the slave end might be straightline in a substantially horizontal or vertical direction. (author)

  5. Privacy preserving interactive record linkage (PPIRL).

    Science.gov (United States)

    Kum, Hye-Chung; Krishnamurthy, Ashok; Machanavajjhala, Ashwin; Reiter, Michael K; Ahalt, Stanley

    2014-01-01

    Record linkage to integrate uncoordinated databases is critical in biomedical research using Big Data. Balancing privacy protection against the need for high quality record linkage requires a human-machine hybrid system to safely manage uncertainty in the ever changing streams of chaotic Big Data. In the computer science literature, private record linkage is the most published area. It investigates how to apply a known linkage function safely when linking two tables. However, in practice, the linkage function is rarely known. Thus, there are many data linkage centers whose main role is to be the trusted third party to determine the linkage function manually and link data for research via a master population list for a designated region. Recently, a more flexible computerized third-party linkage platform, Secure Decoupled Linkage (SDLink), has been proposed based on: (1) decoupling data via encryption, (2) obfuscation via chaffing (adding fake data) and universe manipulation; and (3) minimum information disclosure via recoding. We synthesize this literature to formalize a new framework for privacy preserving interactive record linkage (PPIRL) with tractable privacy and utility properties and then analyze the literature using this framework. Human-based third-party linkage centers for privacy preserving record linkage are the accepted norm internationally. We find that a computer-based third-party platform that can precisely control the information disclosed at the micro level and allow frequent human interaction during the linkage process, is an effective human-machine hybrid system that significantly improves on the linkage center model both in terms of privacy and utility.

  6. Why are not there more Atlantic salmon (Salmo salar)

    Energy Technology Data Exchange (ETDEWEB)

    Parrish, D. L. [Vermont Univ., School of Natural Resources, Vermont Cooperative Fish and Wildlife Research Unit, Burlington, VT (United States); Behnke, R. J. [Colorado State Univ., Dept. of Fishery and Wildlife Biology, Fort Collins, CO (United States); Gephard, S. R. [Connecticut Dept. of Environmnetal Protection, Fisheries Div., Old Lyme, CT (United States); McCormick, S. D. [Anadromous Fish Research Center, USGS/Biological Resources Div., Turners Falls, MA (United States); Reeves, G. H. [USDA Forest Service, Corvallis, OR (United States)

    1998-12-31

    The causes of decline and extirpation of salmon on a global scale are investigated. In some cases single factors such as dams, pollution and dewatering, increased density of humans near salmon rivers, overfishing, changes in ocean conditions or intensive aquaculture could be identified as likely causes. The available evidence is not sufficient to link cause and effect for most declines because they are the result of multiple factors, and data that would help to discriminate factors on scales of space or time are lacking. For this reason, it is not possible to allocate the proportional impact of multiple factors that contribute to the the demise of salmon populations. More rigorous methodologies, including more effective sampling techniques, testing of multiple effects integrated across space and time, and adaptive management are needed to account for the continuing decline of salmon.

  7. Genome scan for linkage to asthma using a linkage disequilibrium-lod score test.

    Science.gov (United States)

    Jiang, Y; Slager, S L; Huang, J

    2001-01-01

    We report a genome-wide linkage study of asthma on the German and Collaborative Study on the Genetics of Asthma (CSGA) data. Using a combined linkage and linkage disequilibrium test and the nonparametric linkage score, we identified 13 markers from the German data, 1 marker from the African American (CSGA) data, and 7 markers from the Caucasian (CSGA) data in which the p-values ranged between 0.0001 and 0.0100. From our analysis and taking into account previous published linkage studies of asthma, we suggest that three regions in chromosome 5 (around D5S418, D5S644, and D5S422), one region in chromosome 6 (around three neighboring markers D6S1281, D6S291, and D6S1019), one region in chromosome 11 (around D11S2362), and two regions in chromosome 12 (around D12S351 and D12S324) especially merit further investigation.

  8. VT Wildlife Linkage Habitat

    Data.gov (United States)

    Vermont Center for Geographic Information — (Link to Metadata) The Wildlife Linkage Habitat Analysis uses landscape scale data to identify or predict the location of potentially significant wildlife linkage...

  9. 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

  10. Infection experiments with novel Piscine orthoreovirus from rainbow trout (Oncorhynchus mykiss in salmonids.

    Directory of Open Access Journals (Sweden)

    Helena Hauge

    Full Text Available A new disease in farmed rainbow trout (Onchorhyncus mykiss was described in Norway in 2013. The disease mainly affected the heart and resembled heart and skeletal muscle inflammation (HSMI in Atlantic salmon (Salmo salar L.. HSMI is associated with Piscine orthoreovirus (PRV, and a search for a similar virus in the diseased rainbow trout led to detection of a sequence with 85% similarity to PRV. This finding called for a targeted effort to assess the risk the new PRV-variant pose on farmed rainbow trout and Atlantic salmon by studying infection and disease pathogenesis, aiming to provide more diagnostic knowledge. Based on the genetic relationship to PRV, the novel virus is referred to as PRV-Oncorhynchus mykiss (PRV-Om in contrast to PRV-Salmo salar (PRV-Ss. In experimental trials, intraperitoneally injected PRV-Om was shown to replicate in blood in both salmonid species, but more effectively in rainbow trout. In rainbow trout, the virus levels peaked in blood and heart of cohabitants 6 weeks post challenge, along with increased expression of antiviral genes (Mx and viperin in the spleen, with 80-100% of the cohabitants infected. Heart inflammation was diagnosed in all cohabitants examined 8 weeks post challenge. In contrast, less than 50% of the Atlantic salmon cohabitants were infected between 8 and 16 weeks post challenge and the antiviral response in these fish was very low. From 12 weeks post challenge and onwards, mild focal myocarditis was demonstrated in a few virus-positive salmon. In conclusion, PRV-Om infects both salmonid species, but faster transmission, more notable antiviral response and more prominent heart pathology were observed in rainbow trout.

  11. If and when: Intrinsic differences and environmental stressors influence migration in brown trout (Salmo trutta)

    DEFF Research Database (Denmark)

    Peiman, K. S.; Birnie-Gauvin, Kim; Midwood, J. D.

    2017-01-01

    Partial migration is a common phenomenon, yet the causes of individual differences in migratory propensity are not well understood. We examined factors that potentially influence timing of migration and migratory propensity in a wild population of juvenile brown trout (Salmo trutta) by combining...

  12. Design of special planar linkages

    CERN Document Server

    Zhao, Jing-Shan; Ma, Ning; Chu, Fulei

    2013-01-01

    Planar linkages play a very important role in mechanical engineering. As the simplest closed chain mechanisms, planar four-bar linkages are widely used in mechanical engineering, civil engineering and aerospace engineering.Design of Special Planar Linkages proposes a uniform design theory for planar four-bar linkages. The merit of the method proposed in this book is that it allows engineers to directly obtain accurate results when there are such solutions for the specified n precise positions; otherwise, the best approximate solutions will be found. This book discusses the kinematics and reach

  13. Dicty_cDB: VHE867 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available VH (Link to library) VHE867 (Link to dictyBase) - G02701 DDB0204977 Contig-U14789-1... - (Link to Original site) VHE867F 383 - - - - - - Show VHE867 Library VH (Link to library) Clone ID VHE867 (Link to dict...yBase) Atlas ID - NBRP ID G02701 dictyBase ID DDB0204977 Link to Contig Contig-U14789-1 Original site URL http://dict...one) Salmo salar clone ssal-rgb2-599-16... 116 2e-25 DQ363469_1( DQ363469 |pid:none) Ict...m_ : 1.00 40.0 %: cytoplasmic 36.0 %: nuclear 12.0 %: cytoskeletal 8.0 %: mitochondrial 4.0 %: peroxisomal >> predict

  14. Moritella viscosa, a pathogenic bacterium affecting the fillet quality in fish

    DEFF Research Database (Denmark)

    Ingerslev, Hans-Christian; Nielsen, Michael Engelbrecht

    2011-01-01

    Moritella viscosa is a bacterium belonging to the family Moritellaceae and was formerly known as Vibrio viscosus. The name ‘viscosa’ originates from the slimy nature of the bacterium. M. viscosa is considered to be the main causative agent of the phenomenon ‘winter ulcer’ or ‘cold-water ulcer......’ which affects various fish species in seawater during cold periods (Lunder et al. 1995). The bacterium is mainly a problem for farmed salmonid species, such as Atlantic salmon (Salmo salar) and rainbow trout (Oncorhynchus mykiss), but has also been isolated from other fish species, including Atlantic...... market price because of a quality downgrade caused by textural changes in the fillet....

  15. Dicty_cDB: Contig-U12832-1 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available N... 44 5.2 1 ( CV571667 ) oe15g07.y1 Human keratoconus cornea, unamplified,... 44 5.2 1 ( AI973283 ) wr54c0...Name: Full=E3 ubiquitin-protein ligase RNF19B; ... 41 0.024 (Q17RB8) RecName: Full=LON peptidase N-terminal ...urpuratus clone R3-3082J12, W... 38 0.34 6 ( EK301514 ) 1095462366289 Global-Ocean-Sampli...RI-214 Salmo salar genomic clone S... 44 5.2 1 ( ER301481 ) 1092343697994 Global-Ocean-Sampli...Y598454_1( AY598454 |pid:none) Danio rerio transcriptional interm... 39 0.070 CR853286_7( CR853286 |pid:none

  16. Development of spinal deformities in Atlantic salmon and Arctic charr fed diets supplemented with oxytetracycline

    International Nuclear Information System (INIS)

    Toften, H.; Jobling, M.

    1996-01-01

    Some individuals within populations of Atlantic salmon Salmo salar and Arctic charr Salvelinus alpinus fed diets supplemented with oxytetracycline (OTC) developed spinal deformations. Possible differences in feed intake and growth of spinally deformed fish relative to fish without any deformities were investigated. Amongst Atlantic salmon, 17% of the fish fed OTC-supplemented feed developed spinal fractures, whereas none of the fish receiving the basic feed did so. Despite deformation of the spinal column, the injured fish continued to feed and grow, but at lower rates than unaffected individuals. In contrast to Atlantic salmon, Arctic charr showed no signs of spinal fractures at any time during the 65-day experiment

  17. Development of spinal deformities in Atlantic salmon and Arctic charr fed diets supplemented with oxytetracycline

    Energy Technology Data Exchange (ETDEWEB)

    Toften, H.; Jobling, M. [Norwegian Institute of Fisheries and Aquaculture, N-9005 Tromsoe (Norway)

    1996-07-01

    Some individuals within populations of Atlantic salmon Salmo salar and Arctic charr Salvelinus alpinus fed diets supplemented with oxytetracycline (OTC) developed spinal deformations. Possible differences in feed intake and growth of spinally deformed fish relative to fish without any deformities were investigated. Amongst Atlantic salmon, 17% of the fish fed OTC-supplemented feed developed spinal fractures, whereas none of the fish receiving the basic feed did so. Despite deformation of the spinal column, the injured fish continued to feed and grow, but at lower rates than unaffected individuals. In contrast to Atlantic salmon, Arctic charr showed no signs of spinal fractures at any time during the 65-day experiment.

  18. Judging a salmon by its spots: environmental variation is the primary determinant of spot patterns in Salmo salar.

    Science.gov (United States)

    Jørgensen, Katarina M; Solberg, Monica F; Besnier, Francois; Thorsen, Anders; Fjelldal, Per Gunnar; Skaala, Øystein; Malde, Ketil; Glover, Kevin A

    2018-04-12

    In fish, morphological colour changes occur from variations in pigment concentrations and in the morphology, density, and distribution of chromatophores in the skin. However, the underlying mechanisms remain unresolved in most species. Here, we describe the first investigation into the genetic and environmental basis of spot pattern development in one of the world's most studied fishes, the Atlantic salmon. We reared 920 salmon from 64 families of domesticated, F1-hybrid and wild origin in two contrasting environments (Hatchery; tanks for the freshwater stage and sea cages for the marine stage, and River; a natural river for the freshwater stage and tanks for the marine stage). Fish were measured, photographed and spot patterns evaluated. In the Hatchery experiment, significant but modest differences in spot density were observed among domesticated, F1-hybrid (1.4-fold spottier than domesticated) and wild salmon (1.7-fold spottier than domesticated). A heritability of 6% was calculated for spot density, and a significant QTL on linkage group SSA014 was detected. In the River experiment, significant but modest differences in spot density were also observed among domesticated, F1-hybrid (1.2-fold spottier than domesticated) and wild salmon (1.8-fold spottier than domesticated). Domesticated salmon were sevenfold spottier in the Hatchery vs. River experiment. While different wild populations were used for the two experiments, on average, these were 6.2-fold spottier in the Hatchery vs. River experiment. Fish in the Hatchery experiment displayed scattered to random spot patterns while fish in the River experiment displayed clustered spot patterns. These data demonstrate that while genetics plays an underlying role, environmental variation represents the primary determinant of spot pattern development in Atlantic salmon.

  19. Metales pesados en Trucha Común (Salmo trutta fario.

    Directory of Open Access Journals (Sweden)

    LEGORBURU, I., CANTON, L., MILLAN, E., CASADO, A., ALVAREZ, J.

    1988-01-01

    Full Text Available Se han determinado las concentraciones de metal en hígado branquia y músculo de Trucha común (Salmo trutta fario, procedente de cinco puntos de la cuenca del río Urola. las muestras se analizaron por espectroscopía de absorción atómica, tras su digestión ácida. La distribución de concentraciones es de tipo normal-logarítmico y existe una retención preferente de aluminio, manganeso y zinc en las branquias, mientras el hígado acumula cadmio, hierro y cobre.

  20. Efficient Record Linkage Algorithms Using Complete Linkage Clustering.

    Science.gov (United States)

    Mamun, Abdullah-Al; Aseltine, Robert; Rajasekaran, Sanguthevar

    2016-01-01

    Data from different agencies share data of the same individuals. Linking these datasets to identify all the records belonging to the same individuals is a crucial and challenging problem, especially given the large volumes of data. A large number of available algorithms for record linkage are prone to either time inefficiency or low-accuracy in finding matches and non-matches among the records. In this paper we propose efficient as well as reliable sequential and parallel algorithms for the record linkage problem employing hierarchical clustering methods. We employ complete linkage hierarchical clustering algorithms to address this problem. In addition to hierarchical clustering, we also use two other techniques: elimination of duplicate records and blocking. Our algorithms use sorting as a sub-routine to identify identical copies of records. We have tested our algorithms on datasets with millions of synthetic records. Experimental results show that our algorithms achieve nearly 100% accuracy. Parallel implementations achieve almost linear speedups. Time complexities of these algorithms do not exceed those of previous best-known algorithms. Our proposed algorithms outperform previous best-known algorithms in terms of accuracy consuming reasonable run times.

  1. North-South Business Linkages

    DEFF Research Database (Denmark)

    Sørensen, Olav Jull; Kuada, John

    2006-01-01

    Based on empirical studies of linkages between TNCs and local firms in India, Malaysia, Vietnam, Ghana and South Africa, five themes are discussed and related to present theoretical perspectives. The themes are (1) Linakge Governance; (2) Globalisation and the dynamics in developing countries (the...... TNC-driven markets in developing countries); (3) The upgrading impact of FDI; (4) Non-equity linkages as a platform for business development, and (5) The learning perspective on international business linakges. The chapter offers at the end a three-dimanional model for impacts of business linkages....

  2. 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.

  3. Oxidative stress and partial migration in brown trout (Salmo trutta)

    DEFF Research Database (Denmark)

    Birnie-Gauvin, Kim; Peiman, K. S.; Larsen, Martin Hage

    2017-01-01

    of oxidative status in migration biology, particularly in fish. Semi-anadromous brown trout (Salmo trutta, Linnaeus 1758) exhibit partial migration, where some individuals smoltify and migrate to sea, and others become stream residents, providing us with an excellent model to investigate the link between...... oxidative stress and migration. Using the brown trout, we obtained blood samples from juveniles from a coastal stream in Denmark in the fall prior to peak seaward migration which occurs in the spring, and assayed for antioxidant capacity (oxygen radical absorbance capacity) and oxidative stress levels...

  4. Genetic monitoring of supportive breeding in brown trout ( Salmo trutta L.), using microsatellite DNA markers

    DEFF Research Database (Denmark)

    Hansen, Michael Møller; Eg Nielsen, Einar; Ruzzante, D.E.

    2000-01-01

    loci in samples of wild and hatchery-reared brown trout (Salmo trutta) from three populations subject to supportive breeding. For calibrating statistical procedures, we included two test samples of reared offspring for which the precise number of parent fish was known and a sample from a further wild...

  5. Evaluation of the hydrogeological interconnection between the Salar de Maricunga and the Piedra Pomez basins, Atacama Region, Chile; An isotope and geochemical approach

    International Nuclear Information System (INIS)

    Iriarte, S.; Santibanez, I; Aravena, R

    2001-01-01

    Groundwater is the main water source for the mining industry in the Altiplano of northern Chile. Groundwater also plays a significant role as a water source for lagoons, wetlands and salares, which are important ecosystems for animal life and vegetation communities that exist in this arid region. The rational use and protection of the groundwater resource requires a good understanding of the aquifer systems. One of the key components in the assessment of water resources in Northern Chile, is the hydrogeological interconnection between basins. During the last three years, as part of a major hydrogeological project, Sernageomin has been working in the Altiplano of the Atacama region (Iriarte et al., 1998; Iriarte, 1999; Venegas et al., 2000; Santibanez, in prep.). This study included the evaluation of the geometry and groundwater potential of the aquifers and the chemical characterization of the surface and groundwater. Part of this study has focused on the Salar de Maricunga and the Campo de Piedra Pomez basins, due to an increasing demand for groundwater resources in this area by the mining industry. This paper discusses the use of isotope and geochemical tools that were used to evaluate the hydrogeological interconnection between the Salar de Maricunga and the Piedra Pomez basins. The geological and hydrogeological framework of this work is discussed in detail by Iriarte (1999) (au)

  6. Soya Saponins Induce Enteritis in Atlantic Salmon (Salmo salar L.).

    Science.gov (United States)

    Krogdahl, Åshild; Gajardo, Karina; Kortner, Trond M; Penn, Michael; Gu, Min; Berge, Gerd Marit; Bakke, Anne Marie

    2015-04-22

    Soybean meal-induced enteritis (SBMIE) is a well-described condition in the distal intestine of salmonids, and saponins have been implicated as the causal agent. However, the question remains whether saponins alone cause SBMIE. Moreover, the dose-response relationship has not been described. In a 10 week feeding trial with Atlantic salmon, a highly purified (95%) soya saponin preparation was supplemented (0, 2, 4, 6, or 10 g/kg) to two basal diets, one containing fishmeal as the major protein source (FM) and the other 25% lupin meal (LP). Saponins caused dose-dependent increases in the severity of inflammation independent of the basal diet, with concomitant alterations in digestive functions and immunological marker expression. Thus, saponins induced inflammation whether the diet contained other legume components or not. However, responses were often the same or stronger in fish fed the corresponding saponin-supplemented LP diets despite lower saponin exposure, suggesting potentiation by other legume component(s).

  7. Distribution of emamectin benzoate in Atlantic salmon (Salmo salar L.).

    Science.gov (United States)

    Sevatdal, S; Magnusson, A; Ingebrigtsen, K; Haldorsen, R; Horsberg, T E

    2005-02-01

    The aims of this study were to investigate the content of emamectin in blood, mucus and muscle following field administration of the recommended dose, and correlation with sea lice infection on the same fish (elimination study). The tissue distribution of tritiated emamectin benzoate after a single oral dose in Atlantic salmon was also investigated by means of whole-body autoradiography and scintillation counting (distribution study). In the elimination study, concentrations of emamectin benzoate reached maximum levels of 128, 105 and 68 ng/g (p.p.b.) for blood, mucus and muscle respectively, on day 7, the last day of administration. From day 7, the concentration in the blood declined until concentration was less than the limit of detection on day 77. The concentration was higher in mucus compared with plasma (P emamectin benzoate decreased gradually from the end of treatment (day 7) to day 70 with half-lives of 9.2, 10.0 and 11.3 days in muscle, plasma and mucus respectively. The distribution study demonstrated a high quantity of radioactivity in mucous membranes (gastrointestinal tract, gills) throughout the observation period (56 days). Activity was high in the epiphysis, hypophysis and olfactory rosette throughout the study. The highest activity was observed in the bile, indicating this to be an important route for excretion. The distribution study confirmed the results from the elimination study with respect to concentrations in blood, skin mucous and muscle.

  8. Late Quaternary Paleoclimatic History of Tropical South America From Drilling Lake Titicaca and the Salar de Uyuni

    Science.gov (United States)

    Baker, P. A.; Fritz, S. C.; Seltzer, G. O.; Rigsby, C. A.; Lowenstein, T. K.; Ku, R.

    2003-12-01

    Seven drill cores were recovered from Lake Titicaca during the NSF/ICDP/DOSECC drilling expedition of 2001. Sub-lake floor drilling depths ranged from 53 to 139 m; water depths ranged from 40 to 232 m; recoveries ranged from 75 to 112 percent. Our most detailed multi-proxy analyses to date have been done on Core 2B raised from the central basin of the lake from 232 m water depth, drilled to 139.26 m sub-lakefloor with 140.61 m of total sediment recovered (101 percent). A basal age of 200 Ka is estimated by linear extrapolation from radiocarbon measurements in the upper 25 m of core; Ar-Ar dating of interbedded ashes and U/Th dating of abiogenic aragonites are underway. The volume and lake level of Lake Titicaca have undergone large changes several times during the late Quaternary. Proxies for these water level changes (each of different fidelity) include the ratio of planktonic-to-benthic diatoms, sedimentary carbonate content, and stable isotopic content of organic carbon. The most recent of these changes, has been described previously from earlier piston cores. In the early and middle Holocene the lake fell below its outlet to 85 m below modern level, lake salinity increased several-fold, and the Salar de Uyuni, which receives overflow from Titicaca, dessicated. In contrast, Lake Titicaca was deep, fresh, and overflowing (southward to the Salar de Uyuni) throughout the last glacial maximum from prior to 25,000 BP to at least 15,000 BP. According to extrapolated ages, the penultimate major lowstand of Lake Titicaca occurred prior to 60,000 BP, when seismic evidence indicates that lake level was about 200 m lower than present. Near the end of this lowstand, the lake also became quite saline. There are at least three, and possibly more, older lowstands, each separated temporally by periods in which the lake freshened dramatically and overflowed. These results will be compared with results from previous drilling in the Salar de Uyuni.

  9. [MapDraw: a microsoft excel macro for drawing genetic linkage maps based on given genetic linkage data].

    Science.gov (United States)

    Liu, Ren-Hu; Meng, Jin-Ling

    2003-05-01

    MAPMAKER is one of the most widely used computer software package for constructing genetic linkage maps.However, the PC version, MAPMAKER 3.0 for PC, could not draw the genetic linkage maps that its Macintosh version, MAPMAKER 3.0 for Macintosh,was able to do. Especially in recent years, Macintosh computer is much less popular than PC. Most of the geneticists use PC to analyze their genetic linkage data. So a new computer software to draw the same genetic linkage maps on PC as the MAPMAKER for Macintosh to do on Macintosh has been crying for. Microsoft Excel,one component of Microsoft Office package, is one of the most popular software in laboratory data processing. Microsoft Visual Basic for Applications (VBA) is one of the most powerful functions of Microsoft Excel. Using this program language, we can take creative control of Excel, including genetic linkage map construction, automatic data processing and more. In this paper, a Microsoft Excel macro called MapDraw is constructed to draw genetic linkage maps on PC computer based on given genetic linkage data. Use this software,you can freely construct beautiful genetic linkage map in Excel and freely edit and copy it to Word or other application. This software is just an Excel format file. You can freely copy it from ftp://211.69.140.177 or ftp://brassica.hzau.edu.cn and the source code can be found in Excel's Visual Basic Editor.

  10. From Enclave to Linkage Economies?

    DEFF Research Database (Denmark)

    Hansen, Michael W.

    as the enclave economy par excellence, moving in with fully integrated value chains, extracting resources and exporting them as commodities having virtually no linkages to the local economy. However, new opportunities for promoting linkages are offered by changing business strategies of local African enterprises...... as well as foreign multinational corporations (MNCs). MNCs in extractives are increasingly seeking local linkages as part of their efficiency, risk, and asset-seeking strategies, and linkage programmes are becoming integral elements in many MNCs’ corporate social responsibility (CSR) activities....... At the same time, local African enterprises are eager to, and increasingly capable of, linking up to the foreign investors in order to expand their activities and acquire technology, skills and market access. The changing strategies of MNCs and the improving capabilities of African enterprises offer new...

  11. Challenges in administrative data linkage for research

    Directory of Open Access Journals (Sweden)

    Katie Harron

    2017-12-01

    Full Text Available Linkage of population-based administrative data is a valuable tool for combining detailed individual-level information from different sources for research. While not a substitute for classical studies based on primary data collection, analyses of linked administrative data can answer questions that require large sample sizes or detailed data on hard-to-reach populations, and generate evidence with a high level of external validity and applicability for policy making. There are unique challenges in the appropriate research use of linked administrative data, for example with respect to bias from linkage errors where records cannot be linked or are linked together incorrectly. For confidentiality and other reasons, the separation of data linkage processes and analysis of linked data is generally regarded as best practice. However, the ‘black box’ of data linkage can make it difficult for researchers to judge the reliability of the resulting linked data for their required purposes. This article aims to provide an overview of challenges in linking administrative data for research. We aim to increase understanding of the implications of (i the data linkage environment and privacy preservation; (ii the linkage process itself (including data preparation, and deterministic and probabilistic linkage methods and (iii linkage quality and potential bias in linked data. We draw on examples from a number of countries to illustrate a range of approaches for data linkage in different contexts.

  12. Expression of interest: transcriptomics and the designation of conservation units.

    Science.gov (United States)

    Hansen, Michael M

    2010-05-01

    An important task within conservation genetics consists in defining intraspecific conservation units. Most conceptual frameworks involve two steps: (i) identifying demographically independent units, and (ii) evaluating their degree of adaptive divergence. Whereas a plethora of methods are available for delineating genetic population structure, assessment of functional genetic divergence remains a challenge. In this issue, Tymchuk et al. (2010) study Atlantic salmon (Salmo salar) populations using both microsatellite markers and analysis of global gene expression. They show that important gene expression differences exist that can be interpreted in the context of different ecological conditions experienced by the populations, along with the populations' histories. This demonstrates an important potential role of transcriptomics for designating conservation units.

  13. Anadromous fish behaviour important for fish passage

    International Nuclear Information System (INIS)

    Kynard, B.E.

    1993-01-01

    An understanding of the behavior of target fish species is necessary for proper design, location, and operation of a successful upstream or downstream fishway for anadromous migrants. Important fish behaviors are seasonal and daily timing of migration; rheotaxis and near field behavior; stimulus-response behavior; swimming capability; shoaling behavior; response to physical environmental factors such as illumination, sound, water depth, current velocity, and structure; response to chemicals; and response to biological factors such as competition for space and response to predators. The information on migrant fish behavior is reviewed, using examples from the literature on the behavior of eastern anadromous species, particularly Atlantic salmon (Salmo salar) and American shad (Alosa sapidissima). 87 refs

  14. Growth and Movement in Brown Trout (Salmo trutta) in two Norwegian Rivers

    OpenAIRE

    Skjellevik, Stine Marie

    2012-01-01

    In the present study, using stream-dwelling brown trout (Salmo trutta) as a model species, movement through the summer and autumn in two large Norwegian rivers, River Glomma and River Gudbrandsdalslågen, was observed. In addition fish from each river were sampled for age and growth analysis. The aim of the study was to test for which individual characteristics (sex, body mass, body condition factor, tagging site and cohort) that influenced movement and to test for correlations between grow...

  15. The score statistic of the LD-lod analysis: detecting linkage adaptive to linkage disequilibrium.

    Science.gov (United States)

    Huang, J; Jiang, Y

    2001-01-01

    We study the properties of a modified lod score method for testing linkage that incorporates linkage disequilibrium (LD-lod). By examination of its score statistic, we show that the LD-lod score method adaptively combines two sources of information: (a) the IBD sharing score which is informative for linkage regardless of the existence of LD and (b) the contrast between allele-specific IBD sharing scores which is informative for linkage only in the presence of LD. We also consider the connection between the LD-lod score method and the transmission-disequilibrium test (TDT) for triad data and the mean test for affected sib pair (ASP) data. We show that, for triad data, the recessive LD-lod test is asymptotically equivalent to the TDT; and for ASP data, it is an adaptive combination of the TDT and the ASP mean test. We demonstrate that the LD-lod score method has relatively good statistical efficiency in comparison with the ASP mean test and the TDT for a broad range of LD and the genetic models considered in this report. Therefore, the LD-lod score method is an interesting approach for detecting linkage when the extent of LD is unknown, such as in a genome-wide screen with a dense set of genetic markers. Copyright 2001 S. Karger AG, Basel

  16. Diel resource partitioning among juvenile Atlantic Salmon, Brown Trout, and Rainbow Trout during summer

    Science.gov (United States)

    Johnson, James H.; McKenna, James E.

    2015-01-01

    Interspecific partitioning of food and habitat resources has been widely studied in stream salmonids. Most studies have examined resource partitioning between two native species or between a native species and one that has been introduced. In this study we examine the diel feeding ecology and habitat use of three species of juvenile salmonids (i.e., Atlantic Salmon Salmo salar, Brown Trout Salmo trutta, and Rainbow Trout Oncorhynchus mykiss) in a tributary of Skaneateles Lake, New York. Subyearling Brown Trout and Rainbow Trout fed more heavily from the drift than the benthos, whereas subyearling Atlantic Salmon fed more from the benthos than either species of trout. Feeding activity of Atlantic Salmon and Rainbow Trout was similar, with both species increasing feeding at dusk, whereas Brown Trout had no discernable feeding peak or trough. Habitat availability was important in determining site-specific habitat use by juvenile salmonids. Habitat selection was greater during the day than at night. The intrastream, diel, intraspecific, and interspecific variation we observed in salmonid habitat use in Grout Brook illustrates the difficulty of acquiring habitat use information for widespread management applications.

  17. Probabilistic linkage to enhance deterministic algorithms and reduce data linkage errors in hospital administrative data.

    Science.gov (United States)

    Hagger-Johnson, Gareth; Harron, Katie; Goldstein, Harvey; Aldridge, Robert; Gilbert, Ruth

    2017-06-30

     BACKGROUND: The pseudonymisation algorithm used to link together episodes of care belonging to the same patients in England (HESID) has never undergone any formal evaluation, to determine the extent of data linkage error. To quantify improvements in linkage accuracy from adding probabilistic linkage to existing deterministic HESID algorithms. Inpatient admissions to NHS hospitals in England (Hospital Episode Statistics, HES) over 17 years (1998 to 2015) for a sample of patients (born 13/28th of months in 1992/1998/2005/2012). We compared the existing deterministic algorithm with one that included an additional probabilistic step, in relation to a reference standard created using enhanced probabilistic matching with additional clinical and demographic information. Missed and false matches were quantified and the impact on estimates of hospital readmission within one year were determined. HESID produced a high missed match rate, improving over time (8.6% in 1998 to 0.4% in 2015). Missed matches were more common for ethnic minorities, those living in areas of high socio-economic deprivation, foreign patients and those with 'no fixed abode'. Estimates of the readmission rate were biased for several patient groups owing to missed matches, which was reduced for nearly all groups. CONCLUSION: Probabilistic linkage of HES reduced missed matches and bias in estimated readmission rates, with clear implications for commissioning, service evaluation and performance monitoring of hospitals. The existing algorithm should be modified to address data linkage error, and a retrospective update of the existing data would address existing linkage errors and their implications.

  18. A Formalization of Linkage Analysis

    DEFF Research Database (Denmark)

    Ingolfsdottir, Anna; Christensen, A.I.; Hansen, Jens A.

    In this report a formalization of genetic linkage analysis is introduced. Linkage analysis is a computationally hard biomathematical method, which purpose is to locate genes on the human genome. It is rooted in the new area of bioinformatics and no formalization of the method has previously been ...

  19. The physiological basis of the migration continuum in brown trout ( Salmo trutta)

    DEFF Research Database (Denmark)

    Boel, Mikkel; Aarestrup, Kim; Baktoft, Henrik

    2014-01-01

    Partial migration is common in many animal taxa; however, the physiological variation underpinning migration strategies remains poorly understood. Among salmonid fishes, brown trout (Salmo trutta) is one of the species that exhibits the most complex variation in sympatric migration strategies......, expressed as a migration continuum, ranging from residency to anadromy. In looking at brown trout, our objective with this study was to test the hypothesis that variation in migration strategies is underpinned by physiological variation. Prior to migration, physiological samples were taken from fish...... in brown trout....

  20. Thermally actuated linkage arrangement

    International Nuclear Information System (INIS)

    Anderson, P.M.

    1981-01-01

    A reusable thermally actuated linkage arrangement includes a first link member having a longitudinal bore therein adapted to receive at least a portion of a second link member therein, the first and second members being sized to effect an interference fit preventing relative movement there-between at a temperature below a predetermined temperature. The link members have different coefficients of thermal expansion so that when the linkage is selectively heated by heating element to a temperature above the predetermined temperature, relative longitudinal and/or rotational movement between the first and second link members is enabled. Two embodiments of a thermally activated linkage are disclosed which find particular application in actuators for a grapple head positioning arm in a nuclear reactor fuel handling mechanism to facilitate back-up safety retraction of the grapple head independently from the primary fuel handling mechanism drive system. (author)

  1. Can sea trout Salmo trutta compromise successful eradication of Gyrodactylus salaris by hiding from CFT Legumin (rotenone) treatments?

    DEFF Research Database (Denmark)

    Davidsen, J. G.; Thorstad, E. B.; Baktoft, H.

    2013-01-01

    In this study, 34 anadromous brown trout (sea trout) Salmo trutta were equipped with acoustic transmitters in order to examine whether they performed avoidance behaviour in response to a CFT Legumin (rotenone) treatment in the Norwegian River Vefsna. Migratory behaviour of the S. trutta was monit...

  2. The volitional travel speed varies with reproductive state in mature female brown trout Salmo trutta

    DEFF Research Database (Denmark)

    Svendsen, Jon Christian; Aarestrup, Kim; Dolby, Jes

    2009-01-01

    This study tested the effect of reproduction on the volitional travel speed of mature female brown trout Salmo trutta L. The downstream travel speed in the pre-spawning state was 0·25 m s−1 (95% CI : 0·19, 0·34) while it increased significantly to 0·65 m s−1 (95% CI: 0·49, 0·87) in the post...

  3. 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.

  4. Multiobjective optimization of a steering linkage

    Energy Technology Data Exchange (ETDEWEB)

    Sleesonsom, S.; Bureerat, S. [Sustainable and Infrastructure Research and Development Center, Dept. of Mechanical Engineering, Faculty of Engineering, Khon Kaen University, Khon Kaen (Thailand)

    2016-08-15

    In this paper, multi-objective optimization of a rack-and-pinion steering linkage is proposed. This steering linkage is a common mechanism used in small cars with three advantages as it is simple to construct, economical to manufacture, and compact and easy to operate. In the previous works, many researchers tried to minimize a steering error but minimization of a turning radius is somewhat ignored. As a result, a multi-objective optimization problem is assigned to simultaneously minimize a steering error and a turning radius. The design variables are linkage dimensions. The design problem is solved by the hybrid of multi-objective population-based incremental learning and differential evolution with various constraint handling schemes. The new design strategy leads to effective design of rack-and-pinion steering linkages satisfying both steering error and turning radius criteria.

  5. Multiobjective optimization of a steering linkage

    International Nuclear Information System (INIS)

    Sleesonsom, S.; Bureerat, S.

    2016-01-01

    In this paper, multi-objective optimization of a rack-and-pinion steering linkage is proposed. This steering linkage is a common mechanism used in small cars with three advantages as it is simple to construct, economical to manufacture, and compact and easy to operate. In the previous works, many researchers tried to minimize a steering error but minimization of a turning radius is somewhat ignored. As a result, a multi-objective optimization problem is assigned to simultaneously minimize a steering error and a turning radius. The design variables are linkage dimensions. The design problem is solved by the hybrid of multi-objective population-based incremental learning and differential evolution with various constraint handling schemes. The new design strategy leads to effective design of rack-and-pinion steering linkages satisfying both steering error and turning radius criteria

  6. Saponin-containing subfractions of soybean molasses induce enteritis in the distal intestine of Atlantic salmon

    DEFF Research Database (Denmark)

    Knudsen, D.; Uran, P.; Arnous, Anis

    2007-01-01

    The current work aimed at tracing the causative components for soybean-induced enteritis in Atlantic salmon (Salmo salar L.). Soybean molasses was subjected to phase separation using n-butanol. Three subfractions were obtained as follows: butanol phase, precipitate, and water phase. The biochemical......-phase high-performance liquid chromatography. Finally, sodium dodecyl sulfate-polyacrylamide gel electrophoresis was used to evaluate the size distribution of the proteins present in each fraction. Molasses and the different subfractions were thereafter fed to Atlantic salmon in two successive fish trials....... The level of intestinal inflammation was evaluated by light microscopy using a semiquantitative scoring system. Histological assessments revealed that Atlantic salmon fed a combination of butanol phase and precipitate displayed significant enteritis. Atlantic salmon fed the water phase displayed normal...

  7. GABAergic anxiolytic drug in water increases migration behaviour in salmon

    Science.gov (United States)

    Hellström, Gustav; Klaminder, Jonatan; Finn, Fia; Persson, Lo; Alanärä, Anders; Jonsson, Micael; Fick, Jerker; Brodin, Tomas

    2016-12-01

    Migration is an important life-history event in a wide range of taxa, yet many migrations are influenced by anthropogenic change. Although migration dynamics are extensively studied, the potential effects of environmental contaminants on migratory physiology are poorly understood. In this study we show that an anxiolytic drug in water can promote downward migratory behaviour of Atlantic salmon (Salmo salar) in both laboratory setting and in a natural river tributary. Exposing salmon smolt to a dilute concentration of a GABAA receptor agonist (oxazepam) increased migration intensity compared with untreated smolt. These results implicate that salmon migration may be affected by human-induced changes in water chemical properties, such as acidification and pharmaceutical residues in wastewater effluent, via alterations in the GABAA receptor function.

  8. Some methods for blindfolded record linkage

    Directory of Open Access Journals (Sweden)

    Christen Peter

    2004-06-01

    Full Text Available Abstract Background The linkage of records which refer to the same entity in separate data collections is a common requirement in public health and biomedical research. Traditionally, record linkage techniques have required that all the identifying data in which links are sought be revealed to at least one party, often a third party. This necessarily invades personal privacy and requires complete trust in the intentions of that party and their ability to maintain security and confidentiality. Dusserre, Quantin, Bouzelat and colleagues have demonstrated that it is possible to use secure one-way hash transformations to carry out follow-up epidemiological studies without any party having to reveal identifying information about any of the subjects – a technique which we refer to as "blindfolded record linkage". A limitation of their method is that only exact comparisons of values are possible, although phonetic encoding of names and other strings can be used to allow for some types of typographical variation and data errors. Methods A method is described which permits the calculation of a general similarity measure, the n-gram score, without having to reveal the data being compared, albeit at some cost in computation and data communication. This method can be combined with public key cryptography and automatic estimation of linkage model parameters to create an overall system for blindfolded record linkage. Results The system described offers good protection against misdeeds or security failures by any one party, but remains vulnerable to collusion between or simultaneous compromise of two or more parties involved in the linkage operation. In order to reduce the likelihood of this, the use of last-minute allocation of tasks to substitutable servers is proposed. Proof-of-concept computer programmes written in the Python programming language are provided to illustrate the similarity comparison protocol. Conclusion Although the protocols described in

  9. Molecular pathology of vertebral deformities in hyperthermic Atlantic salmon (Salmo salar

    Directory of Open Access Journals (Sweden)

    Hjelde Kirsti

    2010-07-01

    Full Text Available Abstract Background Hyperthermia has been shown in a number of organisms to induce developmental defects as a result of changes in cell proliferation, differentiation and gene expression. In spite of this, salmon aquaculture commonly uses high water temperature to speed up developmental rate in intensive production systems, resulting in an increased frequency of skeletal deformities. In order to study the molecular pathology of vertebral deformities, Atlantic salmon was subjected to hyperthermic conditions from fertilization until after the juvenile stage. Results Fish exposed to the high temperature regime showed a markedly higher growth rate and a significant higher percentage of deformities in the spinal column than fish reared at low temperatures. By analyzing phenotypically normal spinal columns from the two temperature regimes, we found that the increased risk of developing vertebral deformities was linked to an altered gene transcription. In particular, down-regulation of extracellular matrix (ECM genes such as col1a1, osteocalcin, osteonectin and decorin, indicated that maturation and mineralization of osteoblasts were restrained. Moreover, histological staining and in situ hybridization visualized areas with distorted chondrocytes and an increased population of hypertrophic cells. These findings were further confirmed by an up-regulation of mef2c and col10a, genes involved in chondrocyte hypertrophy. Conclusion The presented data strongly indicates that temperature induced fast growth is severely affecting gene transcription in osteoblasts and chondrocytes; hence change in the vertebral tissue structure and composition. A disrupted bone and cartilage production was detected, which most likely is involved in the higher rate of deformities developed in the high intensive group. Our results are of basic interest for bone metabolism and contribute to the understanding of the mechanisms involved in development of temperature induced vertebral pathology. The findings may further conduce to future molecular tools for assessing fish welfare in practical farming.

  10. Molecular pathology of vertebral deformities in hyperthermic Atlantic salmon (Salmo salar)

    OpenAIRE

    Ytteborg, Elisabeth; Baeverfjord, Grete; Torgersen, Jacob; Hjelde, Kirsti; Takle, Harald

    2010-01-01

    Abstract Background Hyperthermia has been shown in a number of organisms to induce developmental defects as a result of changes in cell proliferation, differentiation and gene expression. In spite of this, salmon aquaculture commonly uses high water temperature to speed up developmental rate in intensive production systems, resulting in an increased frequency of skeletal deformities. In order to study the molecular pathology of vertebral deformities, Atlantic salmon was subjected to hyperther...

  11. Description of a bacterium associated with redmouth disease of rainbow trout (Salmo gairdneri)

    Science.gov (United States)

    Ross, A.J.; Rucker, R.R.; Ewing, W.H.

    1966-01-01

    A description was given of a gram-negative, peritrichously flagellated, fermentative bacterium that was isolated on numerous occasions from kidney tissues of rainbow trout (Salmo gairdneri) afflicted with redmouth disease. Although the bacteria apparently were members of the family Enterobacteriaceae, it was impossible to determine their taxonomic position within the family with certainty. Hence it was recommended that their taxonomic position remain sub judice for the present. As a temporary designation RM bacterium was used. Redmouth disease was transmitted from infected to normal fish through the medium of water.

  12. Regulation of Na+/K+-ATPase activity by nitric oxide in the kidney and gill of the brown trout (Salmo trutta)

    DEFF Research Database (Denmark)

    Tipsmark, Christian K; Madsen, Steffen S

    2003-01-01

    In teleost fish, successful osmoregulation involves controlled ion transport mechanisms in kidney and gill epithelia. In this study, the effect of nitric oxide (NO) on Na(+)/K(+)-ATPase was investigated in vitro in these two tissues in brown trout (Salmo trutta) acclimated to freshwater...

  13. Effect of radioactive iron /sup 59/Fe on the embryogeny of sea-trout (Salmo trutta L. )

    Energy Technology Data Exchange (ETDEWEB)

    Dabrowski, K; Tucholski, S; Czarnocki, J

    1975-01-01

    Accumulation and diffusion of /sup 59/Fe in the eggs of Salmo trutta L. were observed under laboratory conditions. The dynamics of iron budget in the egg with developing embryo were determined. Differences were found in the accumulation and elimination of iron depending on the stage of the embryos development in the eggs at the time when they were put into the radionuclide solution and on the strength of its concentration.

  14. Linkage Behavior and Practices of Agencies in the Agricultural ...

    African Journals Online (AJOL)

    The study examined the linkage behaviour and practices of agencies in the ... institutes; while (61.5%,65.5%and 50.0%) indicated that linkages with universities of ... Existing institutional framework for linkages between research and extension ...

  15. Exploitation of linkage learning in evolutionary algorithms

    CERN Document Server

    Chen, Ying-ping

    2010-01-01

    The exploitation of linkage learning is enhancing the performance of evolutionary algorithms. This monograph examines recent progress in linkage learning, with a series of focused technical chapters that cover developments and trends in the field.

  16. ANALYSIS OF INTER SECTORAL LINKAGES IN SEMARANG REGENCY

    Directory of Open Access Journals (Sweden)

    Fafurida

    2014-03-01

    Full Text Available This research aims to analyze inter economic sectoral linkages and to arrange the Klassen typology of economic sectors in Semarang Regency. The Klassen typology is composed from the result of the linkage analysis. To construct the analysis, this paper also utulizes the input-output analysis. It finds that service sector has the highest backward linkage while farming sector has the highest forward linkage. Based on the Klassen typology analysis, sectors with the highest backward and forward linkages and potential to be the leading sector are farming sector, dan trade, hotel and restaurant sector.Keywords: Backward linkage,forward linkage, Klassen typologyJEL classification number: R15, O21AbstrakPenelitian ini bertujuan untuk mengkaji seberapa besar keterkaitan antar sektor ekonomi di Kabupaten Semarang dan memetakan tipologi Klassennya. Tipologi Klasen disusun berdasarkan hasil perhitungan analisis keterkaitannya. Untuk menyusun analisis tersebut, paper ini juga menggunakan analisis input-output. Hasil penelitian menunjukkan bahwa sektor jasa memiliki keterkaitan ke belakang tertinggi dibandingkan dengan sektor lainnya. Sementara itu, sektor pertanian merupakan sektor yang memiliki keterkaitan ke depan tertinggi. Berdasarkan hasil analisis tipologi Klassen, sektor yang memiliki keterkaitan ke depan dan ke belakang yang tinggi dan dapat menjadi sektor unggulan adalah sektor perdagangan, hotel dan sektor restoran.Kata kunci: Keterkaitan ke belakang, keterkaitan ke depan, tipologi KlassenJEL classification numbers: R15, O21

  17. Posterior probability of linkage and maximal lod score.

    Science.gov (United States)

    Génin, E; Martinez, M; Clerget-Darpoux, F

    1995-01-01

    To detect linkage between a trait and a marker, Morton (1955) proposed to calculate the lod score z(theta 1) at a given value theta 1 of the recombination fraction. If z(theta 1) reaches +3 then linkage is concluded. However, in practice, lod scores are calculated for different values of the recombination fraction between 0 and 0.5 and the test is based on the maximum value of the lod score Zmax. The impact of this deviation of the test on the probability that in fact linkage does not exist, when linkage was concluded, is documented here. This posterior probability of no linkage can be derived by using Bayes' theorem. It is less than 5% when the lod score at a predetermined theta 1 is used for the test. But, for a Zmax of +3, we showed that it can reach 16.4%. Thus, considering a composite alternative hypothesis instead of a single one decreases the reliability of the test. The reliability decreases rapidly when Zmax is less than +3. Given a Zmax of +2.5, there is a 33% chance that linkage does not exist. Moreover, the posterior probability depends not only on the value of Zmax but also jointly on the family structures and on the genetic model. For a given Zmax, the chance that linkage exists may then vary.

  18. Forest-stream linkages: effects of terrestrial invertebrate input and light on diet and growth of brown trout (Salmo trutta in a boreal forest stream.

    Directory of Open Access Journals (Sweden)

    Tibor Erős

    Full Text Available Subsidies of energy and material from the riparian zone have large impacts on recipient stream habitats. Human-induced changes, such as deforestation, may profoundly affect these pathways. However, the strength of individual factors on stream ecosystems is poorly understood since the factors involved often interact in complex ways. We isolated two of these factors, manipulating the flux of terrestrial input and the intensity of light in a 2×2 factorial design, where we followed the growth and diet of two size-classes of brown trout (Salmo trutta and the development of periphyton, grazer macroinvertebrates, terrestrial invertebrate inputs, and drift in twelve 20 m long enclosed stream reaches in a five-month-long experiment in a boreal coniferous forest stream. We found that light intensity, which was artificially increased 2.5 times above ambient levels, had an effect on grazer density, but no detectable effect on chlorophyll a biomass. We also found a seasonal effect on the amount of drift and that the reduction of terrestrial prey input, accomplished by covering enclosures with transparent plastic, had a negative impact on the amount of terrestrial invertebrates in the drift. Further, trout growth was strongly seasonal and followed the same pattern as drift biomass, and the reduction of terrestrial prey input had a negative effect on trout growth. Diet analysis was consistent with growth differences, showing that trout in open enclosures consumed relatively more terrestrial prey in summer than trout living in covered enclosures. We also predicted ontogenetic differences in the diet and growth of old and young trout, where we expected old fish to be more affected by the terrestrial prey reduction, but we found little evidence of ontogenetic differences. Overall, our results showed that reduced terrestrial prey inputs, as would be expected from forest harvesting, shaped differences in the growth and diet of the top predator, brown trout.

  19. Allelic frequencies of two microsatellite loci in four populations of brown trout (Salmo trutta)

    OpenAIRE

    EDIT VARDHAMI; ANILA HODA; ADIOLA BIBA; MANUELA GUALTIERI; MASSIMO MECATTI; AGIM REXHEPI

    2014-01-01

    Two microsatellite loci, Str60Inra and Ssa197, were PCR amplified on 30 individuals for each populations of brown trout (Salmo trutta). A total of 120 individuals were selected from rivers of the Florence province (Italy), Valbona and Cen (Albania), Lepenci (Kosovo). There were identified 32 different alleles for Str60Inra and 41 for the locus Ssa197. Mean number of alleles ranged from 9 (Cen) to 20.5 (Florence). The mean observed and expected heterosygosities values were 0.329 and 0.755, res...

  20. Expression and genomic organization of zonadhesin-like genes in three species of fish give insight into the evolutionary history of a mosaic protein

    Directory of Open Access Journals (Sweden)

    Davidson William S

    2005-11-01

    Full Text Available Abstract Background The mosaic sperm protein zonadhesin (ZAN has been characterized in mammals and is implicated in species-specific egg-sperm binding interactions. The genomic structure and testes-specific expression of zonadhesin is known for many mammalian species. All zonadhesin genes characterized to date consist of meprin A5 antigen receptor tyrosine phosphatase mu (MAM domains, mucin tandem repeats, and von Willebrand (VWD adhesion domains. Here we investigate the genomic structure and expression of zonadhesin-like genes in three species of fish. Results The cDNA and corresponding genomic locus of a zonadhesin-like gene (zlg in Atlantic salmon (Salmo salar were sequenced. Zlg is similar in adhesion domain content to mammalian zonadhesin; however, the domain order is altered. Analysis of puffer fish (Takifugu rubripes and zebrafish (Danio rerio sequence data identified zonadhesin (zan genes that share the same domain order, content, and a conserved syntenic relationship with mammalian zonadhesin. A zonadhesin-like gene in D. rerio was also identified. Unlike mammalian zonadhesin, D. rerio zan and S. salar zlg were expressed in the gut and not in the testes. Conclusion We characterized likely orthologs of zonadhesin in both T. rubripes and D. rerio and uncovered zonadhesin-like genes in S. salar and D. rerio. Each of these genes contains MAM, mucin, and VWD domains. While these domains are associated with several proteins that show prominent gut expression, their combination is unique to zonadhesin and zonadhesin-like genes in vertebrates. The expression patterns of fish zonadhesin and zonadhesin-like genes suggest that the reproductive role of zonadhesin evolved later in the mammalian lineage.

  1. Linkage and related analyses of Barrett's esophagus and its associated adenocarcinomas.

    Science.gov (United States)

    Sun, Xiangqing; Elston, Robert; Falk, Gary W; Grady, William M; Faulx, Ashley; Mittal, Sumeet K; Canto, Marcia I; Shaheen, Nicholas J; Wang, Jean S; Iyer, Prasad G; Abrams, Julian A; Willis, Joseph E; Guda, Kishore; Markowitz, Sanford; Barnholtz-Sloan, Jill S; Chandar, Apoorva; Brock, Wendy; Chak, Amitabh

    2016-07-01

    Familial aggregation and segregation analysis studies have provided evidence of a genetic basis for esophageal adenocarcinoma (EAC) and its premalignant precursor, Barrett's esophagus (BE). We aim to demonstrate the utility of linkage analysis to identify the genomic regions that might contain the genetic variants that predispose individuals to this complex trait (BE and EAC). We genotyped 144 individuals in 42 multiplex pedigrees chosen from 1000 singly ascertained BE/EAC pedigrees, and performed both model-based and model-free linkage analyses, using S.A.G.E. and other software. Segregation models were fitted, from the data on both the 42 pedigrees and the 1000 pedigrees, to determine parameters for performing model-based linkage analysis. Model-based and model-free linkage analyses were conducted in two sets of pedigrees: the 42 pedigrees and a subset of 18 pedigrees with female affected members that are expected to be more genetically homogeneous. Genome-wide associations were also tested in these families. Linkage analyses on the 42 pedigrees identified several regions consistently suggestive of linkage by different linkage analysis methods on chromosomes 2q31, 12q23, and 4p14. A linkage on 15q26 is the only consistent linkage region identified in the 18 female-affected pedigrees, in which the linkage signal is higher than in the 42 pedigrees. Other tentative linkage signals are also reported. Our linkage study of BE/EAC pedigrees identified linkage regions on chromosomes 2, 4, 12, and 15, with some reported associations located within our linkage peaks. Our linkage results can help prioritize association tests to delineate the genetic determinants underlying susceptibility to BE and EAC.

  2. Experiments on the use of sound as a fish deterrent

    International Nuclear Information System (INIS)

    Turnpenny, A.W.H.; Thatcher, K.P.; Wood, R.; Loeffelman, P.H.

    1993-01-01

    This report describes a series of experimental studies into the potential use of acoustic stimuli to deter fish from water intakes at thermal and hydroelectric power stations. The aim was to enlarge the range of candidate signals for testing, and to apply these in more rigorous laboratory trials and to a wider range of estuarine and marine fish species than was possible in previous initial preliminary studies. The trials were also required to investigate the degree to which fish might become habituated to the sound signals, consequently reducing their effectiveness. The species of fish which were of interest in this study were the Atlantic salmon (Salmo salar), sea trout (Salmo trutta), the shads (Alosa fallax, A. alosa), the European eel (Anguilla anguilla), bass (Dicentrarchus labrax), herring (Clupea harengus), whiting (Merlangius merlangus) and cod (Gadus morhua). All of these species are considered to be of conservation and/or commercial importance in Britain today and are potentially vulnerable to capture by nuclear, fossil-fuelled and tidal generating stations. Based on the effectiveness of the signals observed in these trials, a properly developed and sited acoustic fish deterrent system is expected to reduce fish impingement significantly at water intakes. Field trials at an estuarine power station are recommended. (author)

  3. Spatially and temporally fluctuating selection at non-MHC immune genes: evidence from TAP polymorphism in populations of brown trout ( Salmo trutta , L.)

    DEFF Research Database (Denmark)

    Jensen, L.F.; Hansen, Michael Møller; Mensberg, Karen-Lise Dons

    2008-01-01

    Temporal samples of Danish brown trout (Salmo trutta) from populations representing varying geographical scales were analysed using eight putatively neutral microsatellite loci and two microsatellite loci embedded in TAP genes (Transporter associated with Antigen Processing). These genes encode m...

  4. Testing association and linkage using affected-sib-parent study designs.

    Science.gov (United States)

    Millstein, Joshua; Siegmund, Kimberly D; Conti, David V; Gauderman, W James

    2005-11-01

    We have developed a method for jointly testing linkage and association using data from affected sib pairs and their parents. We specify a conditional logistic regression model with two covariates, one that quantifies association (either direct association or indirect association via linkage disequilibrium), and a second that quantifies linkage. The latter covariate is computed based on expected identity-by-descend (ibd) sharing of marker alleles between siblings. In addition to a joint test of linkage and association, our general framework can be used to obtain a linkage test comparable to the mean test (Blackwelder and Elston [1985] Genet. Epidemiol. 2:85-97), and an association test comparable to the Family-Based Association Test (FBAT; Rabinowitz and Laird [2000] Hum. Hered. 50:211-223). We present simulation results demonstrating that our joint test can be more powerful than some standard tests of linkage or association. For example, with a relative risk of 2.7 per variant allele at a disease locus, the estimated power to detect a nearby marker with a modest level of LD was 58.1% by the mean test (linkage only), 69.8% by FBAT, and 82.5% by our joint test of linkage and association. Our model can also be used to obtain tests of linkage conditional on association and association conditional on linkage, which can be helpful in fine mapping. Copyright 2005 Wiley-Liss, Inc.

  5. Fate of 7,12-dimethylbenz(a)anthracene in rainbow trout, Salmo gairdneri

    International Nuclear Information System (INIS)

    Schnitz, A.R.; Squibb, K.S.; O'Connor, J.M.

    1987-01-01

    Polycyclic aromatic hydrocarbons (PAH) are contaminants of surface waters and sediments, especially near urban centers. Although aquatic biota accumulate PAHs from environmental sources, metabolism may be rapid, and biota sampled from contaminated areas often have concentrations lower than might be estimated from bioconcentration factors. In some cases PAH metabolism by aquatic biota may create reactive intermediates, some of which have been related to chronic effects in fishes. This report describes the fate and distribution of 7,12-dimethylbenz(a)anthracene (DMBA) after oral administration to rainbows trout (Salmo gairdneri). Emphasis has been placed on the disposition of DMBA among tissues and on DMBA transformation in the hepatobiliary system

  6. Physiological effects of simultaneous, abrupt seawater entry and sea lice (Lepeophtheirus salmonis) infestation of wild, sea-run brown trout (Salmo trutta) smolts

    NARCIS (Netherlands)

    Wells, A.; Grierson, C.E.; MacKenzie, M.A.; Russon, I.; Middlemiss, C.; Bjorn, P.A.; Finstad, B.; Wendelaar Bonga, S.E.; Todd, C.D.; Hazon, N.

    2006-01-01

    For wild, sea-run brown trout (Salmo trutta) smolts, the physiological consequences of abrupt transfer to seawater and simultaneous challenge with copepodid larvae of the sea louse, Lepeophtheirus salmonis (Kr�yer, 1837), were investigated in the laboratory. Analysis of osmoregulatory, metabolic,

  7. Privacy-preserving record linkage on large real world datasets.

    Science.gov (United States)

    Randall, Sean M; Ferrante, Anna M; Boyd, James H; Bauer, Jacqueline K; Semmens, James B

    2014-08-01

    Record linkage typically involves the use of dedicated linkage units who are supplied with personally identifying information to determine individuals from within and across datasets. The personally identifying information supplied to linkage units is separated from clinical information prior to release by data custodians. While this substantially reduces the risk of disclosure of sensitive information, some residual risks still exist and remain a concern for some custodians. In this paper we trial a method of record linkage which reduces privacy risk still further on large real world administrative data. The method uses encrypted personal identifying information (bloom filters) in a probability-based linkage framework. The privacy preserving linkage method was tested on ten years of New South Wales (NSW) and Western Australian (WA) hospital admissions data, comprising in total over 26 million records. No difference in linkage quality was found when the results were compared to traditional probabilistic methods using full unencrypted personal identifiers. This presents as a possible means of reducing privacy risks related to record linkage in population level research studies. It is hoped that through adaptations of this method or similar privacy preserving methods, risks related to information disclosure can be reduced so that the benefits of linked research taking place can be fully realised. Copyright © 2013 Elsevier Inc. All rights reserved.

  8. 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...

  9. Genome-wide linkage analysis for human longevity

    DEFF Research Database (Denmark)

    Beekman, Marian; Blanché, Hélène; Perola, Markus

    2013-01-01

    Clear evidence exists for heritability of human longevity, and much interest is focused on identifying genes associated with longer lives. To identify such longevity alleles, we performed the largest genome-wide linkage scan thus far reported. Linkage analyses included 2118 nonagenarian Caucasian...

  10. Effects of emergence time and early social rearing environment on behaviour of Atlantic salmon: Consequences for juvenile fitness and smolt migration

    DEFF Research Database (Denmark)

    Larsen, Martin Hage; Johnsson, Jörgen I.; Winberg, Svante

    2015-01-01

    -reared separately or in co-culture for four months to test effects of social rearing environment on behavioural traits. Twenty fish from each of the six treatment groups were then subjected to three individual-based behavioural tests: basal locomotor activity, boldness, and escape response. Following behavioural...... suggested to be coupled with individual behavioural traits. Here, we further investigate the link between timing of spawning nest emergence and behaviour of Atlantic salmon (Salmo salar), test effects of social rearing environment on behavioural traits in fish with different emergence times, and assess...... characterization, the fish were released into a near-natural experimental stream. Results showed differences in escape behaviour between emergence groups in a net restraining test, but the social rearing environment did not affect individual behavioural expression. Emergence time and social environment had...

  11. Tricellulin, occludin and claudin-3 expression in salmon intestine and kidney during salinity adaptation

    DEFF Research Database (Denmark)

    Tipsmark, Christian Kølbæk; Madsen, Steffen

    2012-01-01

    Molecular regulation of tight junctions in osmoregulatory epithelia of euryhaline fishes must be extensive during ontogeny and acclimation to salinity changes. In this study, five tight junction proteins were examined in Atlantic salmon (Salmo salar): tight junction associated tricellulin, occludin...... and claudin-3 isoforms (a, b, c). A survey of tissue distribution in freshwater (FW) salmon showed that tricellulin expression was highest in the intestine. Occludin was detected in tissues with importance for epithelial transport and the order of expression was gill>intestine>kidney. The three claudin-3...... isoforms were expressed at highest level in kidney tissue. Transfer of juvenile FW salmon to seawater (SW) elevated intestinal tricellulin and occludin mRNA, and these transcripts were also elevated at the time of best SW-tolerance during the course of smoltification. In the kidney, expression...

  12. Different immunization routes induce protection against Aeromonas salmonicida through different immune mechanisms in rainbow trout

    DEFF Research Database (Denmark)

    Villumsen, Kasper Rømer; Raida, Martin Kristian

    in fish immunology and vaccinology, resulting in the development of both oral, immersion and injectable vaccine strategies over time. Applying mineral oil adjuvants, injectable vaccines inducing high levels of protection in salmon (Salmo salar) rose to prominence in the 1990’s. In general injectable......, adjuvanted vaccines have been shown to induce long-lasting increases in specific antibody levels. In general the majority of the published work concerning vaccination against A. salmonicida has been conducted on salmon. Using injectable oil-adjuvanted vaccines, we have previously shown that the induced level...... against A. salmonicida. The effect of immersion vaccination against A. salmonicida has been questioned over time. While some have presented excellent protection as a result of immersion vaccines, others have reported limited or absent protective effects. We have performed experiments on the protection...

  13. Ecosystem services provided by the Baltic salmon: a regional perspective to the socio-economic benefits associated with a keystone species

    DEFF Research Database (Denmark)

    Kulmala, Soile; Haapasaari, Päivi Elisabet; Karjalainen, Timo P.

    Key Message: Baltic salmon (Salmo salar L.) is one of the keystone migratory species in the Baltic Sea.In the pastsalmon played a centralrole in the economyand culture of the region. However, salmon population collapsed becauseoflogging, dams for hydropower production, pollution and overfishing....... Todaysalmon is still of great cultural importanceasshownfor exampleby estimates of public spending forhabitat restorationandWTP by angler.Estimates suggest that the cultural services of salmon are greater than the economic value of commercial salmon landingswith a net present value rangingfrom 6 million EUR...... to 25 million EUR (ie 0.9-3.6 million EUR / year) in Denmark, Finland, Poland and Sweden for2009-2015. Baltic salmon plays also an important role in reducing sedimentation, regulating food webs and maintaining the general ecological balance of ecosystems Maintaining and restoring the salmon population...

  14. Quantification of fatty acids in salmon fillets conserved by different methods

    Directory of Open Access Journals (Sweden)

    Renata Menoci Gonçalves

    2017-09-01

    Full Text Available Lipid contents and the composition of fatty acids of fillets from Chilean salmon (Salmo salar were determined under different conservation methods: fresh salmon, frozen salmon, water-conserved canned salmon and frozen salmon in long-term storage. Fatty acid contents were determined by gas chromatography. The fillets had high lipid levels, ranging between 9.71 and 12.86%. All samples presented high levels of monounsaturated fatty acids, between 363.69 and 425.30 mg g-1 of total lipids, followed by polyunsaturated fatty acids (294.46 - 342.45 mg g-1 of total lipids and saturated fatty acids (203.32 - 223.17 mg g-1 of total lipids. Although samples revealed different lipid contents, all proved to be great sources of omega-3 fatty acids, regardless of the manner of conservation.

  15. Identification of FXYD Protein Genes in a Teleost: Tissue-specific Expression and Response to Salinity Change

    DEFF Research Database (Denmark)

    Tipsmark, Christian Kølbæk

    2008-01-01

    identified. Phylogenetic analysis suggests that six isoforms are homologues to the previously identified FXYD2, FXYD5, FXYD6, FXYD7, FXYD8 and FXYD9, while two additional isoforms were found (FXYD11 and FXYD12). Using quantitative PCR, tissue dependent expression of the different isoforms was analyzed......). In osmoregulatory tissues, one isoform was expressed predominantly in gill (FXYD11), one in kidney (FXYD2) and one equally in kidney and intestine (FXYD12). Expression of several FXYD genes in kidney and gill differed between fresh water and seawater salmon suggesting significance during osmoregulatory adaptations....... In addition to identify novel FXYD isoforms, these studies are the first to show the tissue dependence in their expression and modulation by salinity in any teleosts. Key words: Atlantic salmon, Na+,K+-ATPase, Osmoregulation, Salmo salar, QPCR....

  16. Routes and survival of anadromous brown trout Salmo trutta L. post-smolts during early marine migration through a Danish fjord system

    DEFF Research Database (Denmark)

    Kristensen, Martin Lykke; Birnie-Gauvin, Kim; Aarestrup, Kim

    2018-01-01

    We examined the survival and progression rates of 101 anadromous brown trout Salmo trutta L. post-smolts from two Danish river systems, Karup and Simested, with acoustic telemetry as they migrated through a large Danish fjord system (the Limfjord). No fish were documented to residualize permanently...

  17. Fine mapping quantitative trait loci under selective phenotyping strategies based on linkage and linkage disequilibrium criteria

    DEFF Research Database (Denmark)

    Ansari-Mahyari, S; Berg, P; Lund, M S

    2009-01-01

    disequilibrium-based sampling criteria (LDC) for selecting individuals to phenotype are compared to random phenotyping in a quantitative trait loci (QTL) verification experiment using stochastic simulation. Several strategies based on LAC and LDC for selecting the most informative 30%, 40% or 50% of individuals...... for phenotyping to extract maximum power and precision in a QTL fine mapping experiment were developed and assessed. Linkage analyses for the mapping was performed for individuals sampled on LAC within families and combined linkage disequilibrium and linkage analyses was performed for individuals sampled across...... the whole population based on LDC. The results showed that selecting individuals with similar haplotypes to the paternal haplotypes (minimum recombination criterion) using LAC compared to random phenotyping gave at least the same power to detect a QTL but decreased the accuracy of the QTL position. However...

  18. Estimating parameters for probabilistic linkage of privacy-preserved datasets.

    Science.gov (United States)

    Brown, Adrian P; Randall, Sean M; Ferrante, Anna M; Semmens, James B; Boyd, James H

    2017-07-10

    Probabilistic record linkage is a process used to bring together person-based records from within the same dataset (de-duplication) or from disparate datasets using pairwise comparisons and matching probabilities. The linkage strategy and associated match probabilities are often estimated through investigations into data quality and manual inspection. However, as privacy-preserved datasets comprise encrypted data, such methods are not possible. In this paper, we present a method for estimating the probabilities and threshold values for probabilistic privacy-preserved record linkage using Bloom filters. Our method was tested through a simulation study using synthetic data, followed by an application using real-world administrative data. Synthetic datasets were generated with error rates from zero to 20% error. Our method was used to estimate parameters (probabilities and thresholds) for de-duplication linkages. Linkage quality was determined by F-measure. Each dataset was privacy-preserved using separate Bloom filters for each field. Match probabilities were estimated using the expectation-maximisation (EM) algorithm on the privacy-preserved data. Threshold cut-off values were determined by an extension to the EM algorithm allowing linkage quality to be estimated for each possible threshold. De-duplication linkages of each privacy-preserved dataset were performed using both estimated and calculated probabilities. Linkage quality using the F-measure at the estimated threshold values was also compared to the highest F-measure. Three large administrative datasets were used to demonstrate the applicability of the probability and threshold estimation technique on real-world data. Linkage of the synthetic datasets using the estimated probabilities produced an F-measure that was comparable to the F-measure using calculated probabilities, even with up to 20% error. Linkage of the administrative datasets using estimated probabilities produced an F-measure that was higher

  19. RLT-S: A Web System for Record Linkage.

    Directory of Open Access Journals (Sweden)

    Abdullah-Al Mamun

    Full Text Available Record linkage integrates records across multiple related data sources identifying duplicates and accounting for possible errors. Real life applications require efficient algorithms to merge these voluminous data sources to find out all records belonging to same individuals. Our recently devised highly efficient record linkage algorithms provide best-known solutions to this challenging problem.We have developed RLT-S, a freely available web tool, which implements our single linkage clustering algorithm for record linkage. This tool requires input data sets and a small set of configuration settings about these files to work efficiently. RLT-S employs exact match clustering, blocking on a specified attribute and single linkage based hierarchical clustering among these blocks.RLT-S is an implementation package of our sequential record linkage algorithm. It outperforms previous best-known implementations by a large margin. The tool is at least two times faster for any dataset than the previous best-known tools.RLT-S tool implements our record linkage algorithm that outperforms previous best-known algorithms in this area. This website also contains necessary information such as instructions, submission history, feedback, publications and some other sections to facilitate the usage of the tool.RLT-S is integrated into http://www.rlatools.com, which is currently serving this tool only. The tool is freely available and can be used without login. All data files used in this paper have been stored in https://github.com/abdullah009/DataRLATools. For copies of the relevant programs please see https://github.com/abdullah009/RLATools.

  20. Linkage analysis: Inadequate for detecting susceptibility loci in complex disorders?

    Energy Technology Data Exchange (ETDEWEB)

    Field, L.L.; Nagatomi, J. [Univ. of Calgary, Alberta (Canada)

    1994-09-01

    Insulin-dependent diabetes mellitus (IDDM) may provide valuable clues about approaches to detecting susceptibility loci in other oligogenic disorders. Numerous studies have demonstrated significant association between IDDM and a VNTR in the 5{prime} flanking region of the insulin (INS) gene. Paradoxically, all attempts to demonstrate linkage of IDDM to this VNTR have failed. Lack of linkage has been attributed to insufficient marker locus information, genetic heterogeneity, or high frequency of the IDDM-predisposing allele in the general population. Tyrosine hydroxylase (TH) is located 2.7 kb from INS on the 5` side of the VNTR and shows linkage disequilibrium with INS region loci. We typed a highly polymorphic microsatellite within TH in 176 multiplex families, and performed parametric (lod score) linkage analysis using various intermediate reduced penetrance models for IDDM (including rare and common disease allele frequencies), as well as non-parametric (affected sib pair) linkage analysis. The scores significantly reject linkage for recombination values of .05 or less, excluding the entire 19 kb region containing TH, the 5{prime} VNTR, the INS gene, and IGF2 on the 3{prime} side of INS. Non-parametric linkage analysis also provided no significant evidence for linkage (mean TH allele sharing 52.5%, P=.12). These results have important implications for efforts to locate genes predisposing to complex disorders, strongly suggesting that regions which are significantly excluded by linkage methods may nevertheless contain predisposing genes readily detectable by association methods. We advocate that investigators routinely perform association analyses in addition to linkage analyses.

  1. Detection of QTL for Carcass Quality on Chromosome 6 by Exploiting Linkage and Linkage Disequilibrium in Hanwoo

    Directory of Open Access Journals (Sweden)

    J.-H. Lee

    2012-01-01

    Full Text Available The purpose of this study was to improve mapping power and resolution for the QTL influencing carcass quality in Hanwoo, which was previously detected on the bovine chromosome (BTA 6. A sample of 427 steers were chosen, which were the progeny from 45 Korean proven sires in the Hanwoo Improvement Center, Seosan, Korea. The samples were genotyped with the set of 2,535 SNPs on BTA6 that were imbedded in the Illumina bovine 50 k chip. A linkage disequilibrium variance component mapping (LDVCM method, which exploited both linkage between sires and their steers and population-wide linkage disequilibrium, was applied to detect QTL for four carcass quality traits. Fifteen QTL were detected at 0.1% comparison-wise level, for which five, three, five, and two QTL were associated with carcass weight (CWT, backfat thickness (BFT, longissimus dorsi muscle area (LMA, and marbling score (Marb, respectively. The number of QTL was greater compared with our previous results, in which twelve QTL for carcass quality were detected on the BTA6 in the same population by applying other linkage disequilibrium mapping approaches. One QTL for LMA was detected on the distal region (110,285,672 to 110,633,096 bp with the most significant evidence for linkage (p<10−5. Another QTL that was detected on the proximal region (33,596,515 to 33,897,434 bp was pleiotrophic, i.e. influencing CWT, BFT, and LMA. Our results suggest that the LDVCM is a good alternative method for QTL fine-mapping in detection and characterization of QTL.

  2. A general model for likelihood computations of genetic marker data accounting for linkage, linkage disequilibrium, and mutations.

    Science.gov (United States)

    Kling, Daniel; Tillmar, Andreas; Egeland, Thore; Mostad, Petter

    2015-09-01

    Several applications necessitate an unbiased determination of relatedness, be it in linkage or association studies or in a forensic setting. An appropriate model to compute the joint probability of some genetic data for a set of persons given some hypothesis about the pedigree structure is then required. The increasing number of markers available through high-density SNP microarray typing and NGS technologies intensifies the demand, where using a large number of markers may lead to biased results due to strong dependencies between closely located loci, both within pedigrees (linkage) and in the population (allelic association or linkage disequilibrium (LD)). We present a new general model, based on a Markov chain for inheritance patterns and another Markov chain for founder allele patterns, the latter allowing us to account for LD. We also demonstrate a specific implementation for X chromosomal markers that allows for computation of likelihoods based on hypotheses of alleged relationships and genetic marker data. The algorithm can simultaneously account for linkage, LD, and mutations. We demonstrate its feasibility using simulated examples. The algorithm is implemented in the software FamLinkX, providing a user-friendly GUI for Windows systems (FamLinkX, as well as further usage instructions, is freely available at www.famlink.se ). Our software provides the necessary means to solve cases where no previous implementation exists. In addition, the software has the possibility to perform simulations in order to further study the impact of linkage and LD on computed likelihoods for an arbitrary set of markers.

  3. Mapping of yield, yield stability, yield adaptability and other traits in barley using linkage disequilibrium mapping and linkage analysis

    NARCIS (Netherlands)

    Kraakman, A.T.W.

    2005-01-01

    Plants is mostly done through linkage analysis. A segregating mapping population Identification and mappping of Quantitative Trait Loci (QTLs) in is created from a bi-parental cross and linkages between trait values and mapped markers reveal the positions ofQTLs. In

  4. Two-locus linkage analysis in multiple sclerosis (MS)

    Energy Technology Data Exchange (ETDEWEB)

    Tienari, P.J. (National Public Health Institute, Helsinki (Finland) Univ. of Helsinki (Finland)); Terwilliger, J.D.; Ott, J. (Columbia Univ., New York (United States)); Palo, J. (Univ. of Helsinki (Finland)); Peltonen, L. (National Public Health Institute, Helsinki (Finland))

    1994-01-15

    One of the major challenges in genetic linkage analyses is the study of complex diseases. The authors demonstrate here the use of two-locus linkage analysis in multiple sclerosis (MS), a multifactorial disease with a complex mode of inheritance. In a set of Finnish multiplex families, they have previously found evidence for linkage between MS susceptibility and two independent loci, the myelin basic protein gene (MBP) on chromosome 18 and the HLA complex on chromosome 6. This set of families provides a unique opportunity to perform linkage analysis conditional on two loci contributing to the disease. In the two-trait-locus/two-marker-locus analysis, the presence of another disease locus is parametrized and the analysis more appropriately treats information from the unaffected family member than single-disease-locus analysis. As exemplified here in MS, the two-locus analysis can be a powerful method for investigating susceptibility loci in complex traits, best suited for analysis of specific candidate genes, or for situations in which preliminary evidence for linkage already exists or is suggested. 41 refs., 6 tabs.

  5. Genetic structure and demographic history of brown trout ( Salmo trutta ) populations from the southern Balkans

    DEFF Research Database (Denmark)

    Apostolidis, A.P.; Madeira, M.J.; Hansen, Michael Møller

    2008-01-01

    1. The present study was designed to characterize the genetic structure of brown trout (Salmo trutta) populations from the southern Balkans and to assess the spread of non-native strains and their introgression into native trout gene pools. We analysed polymorphism at nine microsatellite loci...... in seven supposedly non-admixed and three stocked brown trout populations. 2. The analyses confirmed the absence of immigration and extraordinarily strong genetic differentiation among the seven non-introgressed populations in parallel with low levels of intrapopulation genetic variability. In contrast...

  6. Using Bureaucratic and Cultural Linkages to Improve Instruction: The Principal's Contribution.

    Science.gov (United States)

    Firestone, William A.; Wilson, Bruce L.

    1985-01-01

    Principals can influence teachers and instructional behavior by working through linkage mechanisms within the organizational structure of the school. Two types of linkages are identified: bureaucratic and cultural. Principals have access to linkages of both kinds; using linkages effectively, they can generate a common purpose in their schools. (MD)

  7. Fate of Tetracapsuloides bryosalmonae (Myxozoa) after infection of brown trout Salmo trutta and rainbow trout Oncorhynchus mykiss

    OpenAIRE

    Kumar, Gokhlesh; Abd-Elfattah, Ahmed; Saleh, Mona; El-Matbouli, Mansour

    2013-01-01

    Tetracapsuloides bryosalmonae (Myxozoa) is the causative agent of proliferative kidney disease in salmonids. We assessed differences in intensity of T. bryosalmonae infection between brown trout Salmo trutta and rainbow trout Oncorhynchus mykiss from the clinical phase of infection onwards. Specific pathogen-free fish were exposed to T. bryosalmonae spores under controlled laboratory conditions and sampled at 6, 8, 10, 12, 14, and 17 wk post exposure (wpe), and the transmission of T. bryosalm...

  8. Relationship between gill Na+,K+-ATPase activity and downstream movement in domesticated and first-generation offspring of wild anadromous brown trout ( Salmo trutta )

    DEFF Research Database (Denmark)

    Aarestrup, Kim; Nielsen, C.; Madsen, S.S.

    2000-01-01

    The relationship between smolt status and downstream movement following release was investigated in two stocks of hatchery- reared anadromous brown trout (Salmo trutta). Yearlings from a domesticated stock (DS) and first-generation offspring (F1) of wild anadromous trout were held under identical...

  9. Reliable collection of Caspian brown trout (Salmo trutta caspius) sperm using a catheter.

    Science.gov (United States)

    Aramli, M S; Golshahi, K; Banan, A; Sotoudeh, E

    2016-10-01

    The traditional stripping procedure for collecting fish semen is associated with the risk of urine contamination, which may significantly affect semen quality and quantity. The use of a catheter as an alternative method for semen collection may overcome this problem. Therefore, this study compared Caspian brown trout (Salmo trutta caspius) semen parameters (i.e. sperm density, seminal plasma osmolality, motility parameters of spermatozoa analysed using computer-assisted sperm analysis and fertility) between the traditional stripping method and the use of a catheter. All parameter values of the semen collected with a catheter were significantly higher (p brown trout sperm. © 2016 Blackwell Verlag GmbH.

  10. Distribution of lod scores in oligogenic linkage analysis.

    Science.gov (United States)

    Williams, J T; North, K E; Martin, L J; Comuzzie, A G; Göring, H H; Blangero, J

    2001-01-01

    In variance component oligogenic linkage analysis it can happen that the residual additive genetic variance bounds to zero when estimating the effect of the ith quantitative trait locus. Using quantitative trait Q1 from the Genetic Analysis Workshop 12 simulated general population data, we compare the observed lod scores from oligogenic linkage analysis with the empirical lod score distribution under a null model of no linkage. We find that zero residual additive genetic variance in the null model alters the usual distribution of the likelihood-ratio statistic.

  11. Data Linkage: A powerful research tool with potential problems

    Directory of Open Access Journals (Sweden)

    Scott Ian

    2010-12-01

    Full Text Available Abstract Background Policy makers, clinicians and researchers are demonstrating increasing interest in using data linked from multiple sources to support measurement of clinical performance and patient health outcomes. However, the utility of data linkage may be compromised by sub-optimal or incomplete linkage, leading to systematic bias. In this study, we synthesize the evidence identifying participant or population characteristics that can influence the validity and completeness of data linkage and may be associated with systematic bias in reported outcomes. Methods A narrative review, using structured search methods was undertaken. Key words "data linkage" and Mesh term "medical record linkage" were applied to Medline, EMBASE and CINAHL databases between 1991 and 2007. Abstract inclusion criteria were; the article attempted an empirical evaluation of methodological issues relating to data linkage and reported on patient characteristics, the study design included analysis of matched versus unmatched records, and the report was in English. Included articles were grouped thematically according to patient characteristics that were compared between matched and unmatched records. Results The search identified 1810 articles of which 33 (1.8% met inclusion criteria. There was marked heterogeneity in study methods and factors investigated. Characteristics that were unevenly distributed among matched and unmatched records were; age (72% of studies, sex (50% of studies, race (64% of studies, geographical/hospital site (93% of studies, socio-economic status (82% of studies and health status (72% of studies. Conclusion A number of relevant patient or population factors may be associated with incomplete data linkage resulting in systematic bias in reported clinical outcomes. Readers should consider these factors in interpreting the reported results of data linkage studies.

  12. Genome-wide linkage scan for colorectal cancer susceptibility genes supports linkage to chromosome 3q

    Directory of Open Access Journals (Sweden)

    Velculescu Victor E

    2008-04-01

    Full Text Available Abstract Background Colorectal cancer is one of the most common causes of cancer-related mortality. The disease is clinically and genetically heterogeneous though a strong hereditary component has been identified. However, only a small proportion of the inherited susceptibility can be ascribed to dominant syndromes, such as Hereditary Non-Polyposis Colorectal Cancer (HNPCC or Familial Adenomatous Polyposis (FAP. In an attempt to identify novel colorectal cancer predisposing genes, we have performed a genome-wide linkage analysis in 30 Swedish non-FAP/non-HNPCC families with a strong family history of colorectal cancer. Methods Statistical analysis was performed using multipoint parametric and nonparametric linkage. Results Parametric analysis under the assumption of locus homogeneity excluded any common susceptibility regions harbouring a predisposing gene for colorectal cancer. However, several loci on chromosomes 2q, 3q, 6q, and 7q with suggestive linkage were detected in the parametric analysis under the assumption of locus heterogeneity as well as in the nonparametric analysis. Among these loci, the locus on chromosome 3q21.1-q26.2 was the most consistent finding providing positive results in both parametric and nonparametric analyses Heterogeneity LOD score (HLOD = 1.90, alpha = 0.45, Non-Parametric LOD score (NPL = 2.1. Conclusion The strongest evidence of linkage was seen for the region on chromosome 3. Interestingly, the same region has recently been reported as the most significant finding in a genome-wide analysis performed with SNP arrays; thus our results independently support the finding on chromosome 3q.

  13. Selenium-induced autometallographic demonstration of endogenous zinc in organs of the rainbow trout, Salmo gairdneri

    DEFF Research Database (Denmark)

    Baatrup, E

    1989-01-01

    , the intestine, and the gills, whereas, no such grains were found in preparations from fish having received 1 ppm Se. The use of selenium for the histochemical demonstration of endogenous zinc versus exogenous metals is discussed. Also, consideration is given to the question of which part of the total tissue......Autometallographic (AMG) silver enhancement of endogenous zinc was studied in seven organs of the rainbow trout Salmo gairdneri. Groups of trout were injected intraperitoneally with sodium selenite in doses ranging from 0.08 to 25 ppm, administered 1 h before being killed. The concentration...

  14. ARTIFICIAL BREEDING OF NERETVA SOFTMOUTH TROUT (Salmo obtusirostris Oxyrhincus Heckel, 1851

    Directory of Open Access Journals (Sweden)

    Dževad Handžar

    2015-06-01

    Full Text Available The paper presents an artificial breeding of softmouth trout (Salmo obtusirostris oxyrhynchus, which is one of the endemic species of fish Neretva basin and which is on the Red List of the International Union for Conservation of Nature (IUCN as endangered species facing extinction. Production of fry softmouth trout intended for restocking is very complex and complicated process, and in this paper, which is based on long experience in artificial breeding softmouth trout, we want to contribute to the conservation and breeding of native salmonid fish and aquaculture development of BiH. The paper describes the production technology and production phase, diet and food as well as the application of preventive and therapeutic measures in production. Key word - softmouth trout, artificial breeding, preventive and therapeutic measures

  15. An estimating function approach to linkage heterogeneity

    Indian Academy of Sciences (India)

    Testing linkage heterogeneity between two loci is an important issue in genetics. Currently, there are ... on linkage heterogeneity can help people to better understand complex .... χ2(F − 2) + cχ2 (1), where c is a constant (see Appendix). Here, it can be ..... gin, ancestry, gender, age, etc., for purpose of dividing sub- groups to ...

  16. Bayesian linkage and segregation analysis: factoring the problem.

    Science.gov (United States)

    Matthysse, S

    2000-01-01

    Complex segregation analysis and linkage methods are mathematical techniques for the genetic dissection of complex diseases. They are used to delineate complex modes of familial transmission and to localize putative disease susceptibility loci to specific chromosomal locations. The computational problem of Bayesian linkage and segregation analysis is one of integration in high-dimensional spaces. In this paper, three available techniques for Bayesian linkage and segregation analysis are discussed: Markov Chain Monte Carlo (MCMC), importance sampling, and exact calculation. The contribution of each to the overall integration will be explicitly discussed.

  17. Mobile assemblies of Bennett linkages from four-crease origami patterns

    Science.gov (United States)

    Zhang, Xiao; Chen, Yan

    2018-02-01

    This paper deals with constructing mobile assemblies of Bennett linkages inspired by four-crease origami patterns. A transition technique has been proposed by taking the thick-panel form of an origami pattern as an intermediate bridge. A zero-thickness rigid origami pattern and its thick-panel form share the same sector angles and folding behaviours, while the thick-panel origami and the mobile assembly of linkages are kinematically equivalent with differences only in link profiles. Applying this transition technique to typical four-crease origami patterns, we have found that the Miura-ori and graded Miura-ori patterns lead to assemblies of Bennett linkages with identical link lengths. The supplementary-type origami patterns with different mountain-valley crease assignments correspond to different types of Bennett linkage assemblies with negative link lengths. And the identical linkage-type origami pattern generates a new mobile assembly. Hence, the transition technique offers a novel approach to constructing mobile assemblies of spatial linkages from origami patterns.

  18. Dimensional threshold for fracture linkage and hooking

    Science.gov (United States)

    Lamarche, Juliette; Chabani, Arezki; Gauthier, Bertrand D. M.

    2018-03-01

    Fracture connectivity in rocks depends on spatial properties of the pattern including length, abundance and orientation. When fractures form a single-strike set, they hardly cross-cut each other and the connectivity is limited. Linkage probability increases with increasing fracture abundance and length as small fractures connect to each other to form longer ones. A process for parallel fracture linkage is the "hooking", where two converging fracture tips mutually deviate and then converge to connect due to the interaction of their crack-tip stresses. Quantifying the processes and conditions for fracture linkage in single-strike fracture sets is crucial to better predicting fluid flow in Naturally Fractured Reservoirs. For 1734 fractures in Permian shales of the Lodève Basin, SE France, we measured geometrical parameters in 2D, characterizing three stages of the hooking process: underlapping, overlapping and linkage. We deciphered the threshold values, shape ratios and limiting conditions to switch from one stage to another one. The hook set up depends on the spacing (S) and fracture length (Lh) with the relation S ≈ 0.15 Lh. Once the hooking is initiated, with the fracture deviation length (L) L ≈ 0.4 Lh, the fractures reaches the linkage stage only when the spacing is reduced to S ≈ 0.02 Lh and the convergence (C) is < 0.1 L. These conditions apply to multi-scale fractures with a shape ratio L/S = 10 and for fracture curvature of 10°-20°.

  19. Improved recapture rate of vaccinated sea-ranched Atlantic salmon, Salmo salar L

    DEFF Research Database (Denmark)

    Buchmann, K.; Larsen, J.L.; Therkildsen, Birgit

    2001-01-01

    vaccine-components and the third group was used as a non-vaccinated control. One month after vaccination these groups were allocated to three separate net-pens located 500 m from the coastline of the island. After 4 months in the net-pens, 1000 fish from each cage were tagged with Carlin-tags below...

  20. Mapping of yield, yield stability, yield adaptability and other traits in barley using linkage disequilibrium mapping and linkage analysis

    OpenAIRE

    Kraakman, A.T.W.

    2005-01-01

    Plants is mostly done through linkage analysis. A segregating mapping population Identification and mappping of Quantitative Trait Loci (QTLs) in is created from a bi-parental cross and linkages between trait values and mapped markers reveal the positions ofQTLs. Inthisstudyweexploredlinkagedisequilibrium(LD)mappingof traits in a set of modernbarleycultivars. LDbetweenmolecularmarkerswasfoundup to a distance of 10 centimorgan,whichislargecomparedtootherspecies.Thelarge distancemightbeinducedb...

  1. Record linkage for pharmacoepidemiological studies in cancer patients.

    Science.gov (United States)

    Herk-Sukel, Myrthe P P van; Lemmens, Valery E P P; Poll-Franse, Lonneke V van de; Herings, Ron M C; Coebergh, Jan Willem W

    2012-01-01

    An increasing need has developed for the post-approval surveillance of (new) anti-cancer drugs by means of pharmacoepidemiology and outcomes research in the area of oncology. To create an overview that makes researchers aware of the available database linkages in Northern America and Europe which facilitate pharmacoepidemiology and outcomes research in cancer patients. In addition to our own database, i.e. the Eindhoven Cancer Registry (ECR) linked to the PHARMO Record Linkage System, we considered database linkages between a population-based cancer registry and an administrative healthcare database that at least contains information on drug use and offers a longitudinal perspective on healthcare utilization. Eligible database linkages were limited to those that had been used in multiple published articles in English language included in Pubmed. The HMO Cancer Research Network (CRN) in the US was excluded from this review, as an overview of the linked databases participating in the CRN is already provided elsewhere. Researchers who had worked with the data resources included in our review were contacted for additional information and verification of the data presented in the overview. The following database linkages were included: the Surveillance, Epidemiology, and End-Results-Medicare; cancer registry data linked to Medicaid; Canadian cancer registries linked to population-based drug databases; the Scottish cancer registry linked to the Tayside drug dispensing data; linked databases in the Nordic Countries of Europe: Norway, Sweden, Finland and Denmark; and the ECR-PHARMO linkage in the Netherlands. Descriptives of the included database linkages comprise population size, generalizability of the population, year of first data availability, contents of the cancer registry, contents of the administrative healthcare database, the possibility to select a cancer-free control cohort, and linkage to other healthcare databases. The linked databases offer a longitudinal

  2. A guide to evaluating linkage quality for the analysis of linked data.

    Science.gov (United States)

    Harron, Katie L; Doidge, James C; Knight, Hannah E; Gilbert, Ruth E; Goldstein, Harvey; Cromwell, David A; van der Meulen, Jan H

    2017-10-01

    Linked datasets are an important resource for epidemiological and clinical studies, but linkage error can lead to biased results. For data security reasons, linkage of personal identifiers is often performed by a third party, making it difficult for researchers to assess the quality of the linked dataset in the context of specific research questions. This is compounded by a lack of guidance on how to determine the potential impact of linkage error. We describe how linkage quality can be evaluated and provide widely applicable guidance for both data providers and researchers. Using an illustrative example of a linked dataset of maternal and baby hospital records, we demonstrate three approaches for evaluating linkage quality: applying the linkage algorithm to a subset of gold standard data to quantify linkage error; comparing characteristics of linked and unlinked data to identify potential sources of bias; and evaluating the sensitivity of results to changes in the linkage procedure. These approaches can inform our understanding of the potential impact of linkage error and provide an opportunity to select the most appropriate linkage procedure for a specific analysis. Evaluating linkage quality in this way will improve the quality and transparency of epidemiological and clinical research using linked data. © The Author 2017. Published by Oxford University Press on behalf of the International Epidemiological Association.

  3. Agriculture–Tourism Linkages in Botswana: Evidence from the ...

    African Journals Online (AJOL)

    Tourism researchers are increasingly recognising that strengthened linkages between the sectors of tourism and agriculture are significant for maximising local multipliers and especially for pro-poor impacts. This article examines the linkages between the tourism and agriculture sectors in Botswana using evidence ...

  4. Availability of Insurance Linkage Programs in U.S. Emergency Departments

    Directory of Open Access Journals (Sweden)

    Mia Kanak

    2014-07-01

    Full Text Available Introduction: As millions of uninsured citizens who use emergency department (ED services are now eligible for health insurance under the Affordable Care Act, the ED is ideally situated to facilitate linkage to insurance. Forty percent of U.S. EDs report having an insurance linkage program. This is the first national study to examine the characteristics of EDs that offer or do not offer these programs. Methods: This was a secondary analysis of data from the National Survey for Preventive Health Services in U.S. EDs conducted in 2008-09. We compared EDs with and without insurance programs across demographic and operational factors using univariate analysis. We then tested our hypotheses using multivariable logistic regression. We also further examined program capacity and priority among the sub-group of EDs with no insurance linkage program. Results: After adjustment, ED-insurance linkage programs were more likely to be located in the West (RR= 2.06, 95% CI = 1.33 – 2.72. The proportion of uninsured patients in an ED, teaching hospital status, and public ownership status were not associated with insurance linkage availability. EDs with linkage programs also offer more preventive services (RR = 1.87, 95% CI = 1.37–2.35 and have greater social worker availability (RR = 1.71, 95% CI = 1.12–2.33 than those who do not. Four of five EDs with a patient mix of ≥25% uninsured and no insurance linkage program reported that they could not offer a program with existing staff and funding. Conclusion: Availability of insurance linkage programs in the ED is not associated with the proportion of uninsured patients served by an ED. Policy or hospital-based interventions to increase insurance linkage should first target the 27% of EDs with high rates of uninsured patients that lack adequate program capacity. Further research on barriers to implementation and cost effectiveness may help to facilitate increased adoption of insurance linkage programs. [West J

  5. Quantifying sources of bias in longitudinal data linkage studies of child abuse and neglect: measuring impact of outcome specification, linkage error, and partial cohort follow-up.

    Science.gov (United States)

    Parrish, Jared W; Shanahan, Meghan E; Schnitzer, Patricia G; Lanier, Paul; Daniels, Julie L; Marshall, Stephen W

    2017-12-01

    Health informatics projects combining statewide birth populations with child welfare records have emerged as a valuable approach to conducting longitudinal research of child maltreatment. The potential bias resulting from linkage misspecification, partial cohort follow-up, and outcome misclassification in these studies has been largely unexplored. This study integrated epidemiological survey and novel administrative data sources to establish the Alaska Longitudinal Child Abuse and Neglect Linkage (ALCANLink) project. Using these data we evaluated and quantified the impact of non-linkage misspecification and single source maltreatment ascertainment use on reported maltreatment risk and effect estimates. The ALCANLink project integrates the 2009-2011 Alaska Pregnancy Risk Assessment Monitoring System (PRAMS) sample with multiple administrative databases through 2014, including one novel administrative source to track out-of-state emigration. For this project we limited our analysis to the 2009 PRAMS sample. We report on the impact of linkage quality, cohort follow-up, and multisource outcome ascertainment on the incidence proportion of reported maltreatment before age 6 and hazard ratios of selected characteristics that are often available in birth cohort linkage studies of maltreatment. Failure to account for out-of-state emigration biased the incidence proportion by 12% (from 28.3% w to 25.2% w ), and the hazard ratio (HR) by as much as 33% for some risk factors. Overly restrictive linkage parameters biased the incidence proportion downwards by 43% and the HR by as much as 27% for some factors. Multi-source linkages, on the other hand, were of little benefit for improving reported maltreatment ascertainment. Using the ALCANLink data which included a novel administrative data source, we were able to observe and quantify bias to both the incidence proportion and HR in a birth cohort linkage study of reported child maltreatment. Failure to account for out

  6. Environment-dependent plasticity and ontogenetic changes in the brain of hatchery-reared Atlantic salmon

    DEFF Research Database (Denmark)

    Näslund, J.; Larsen, Martin Hage; Thomassen, S.T.

    2017-01-01

    enhancement strategies, like environmental enrichment. Here, we investigated the size of the brain in hatcheryreared Atlantic salmon Salmo salar kept at standard (high) and reduced (low) tank densities. In contrast to our predictions, we found that fish reared at high density had larger dry mass of cerebellum...... and telencephalon, correcting for body size. No differences were detected for total brain mass. Furthermore, we found that the relative size of both telencephalon and cerebellum, in relation to total brain mass, changed with body size. Cerebellum increased in relative size with increased body size, while......Lowered rearing density has repeatedly been shown to increase the performance of hatchery-reared salmonids stocked into natural environments. One possible mechanism for this pattern could be that lower densities enhance brain development, which has been shown to be the case in other hatchery...

  7. Variation in some quality attributes of Atlantic salmon fillets from aquaculture related to geographic origin and water temperature

    DEFF Research Database (Denmark)

    Johansson, Gine Ørnholt; Frosch, Stina; Jørgensen, Bo Munk

    2017-01-01

    an efficient use of the information gathered in the different links of the value chain, a deeper knowledge of the correlations between the various quality attributes and factors like the geographical origin of the salmon, the company and the water temperature of the fish farm, is needed. In the present study......It is well know that factors like fat content and texture affect the yield when making products from Atlantic salmon (Salmo salar L.). The relation between these factors and other quality attributes like water holding capacity and protein content, however, has received limited attention. To enable...... a multivariate approach was taken to investigate the variation in some quality parameters (fat, protein, texture, water holding capacity, weight) amongst salmon samples (n = 136) from Norwegian aquaculture in order to establish which parameters were accounting for most of the variation seen in relation...

  8. Linking individual migratory behaviour of Atlantic salmon to their genetic origin

    DEFF Research Database (Denmark)

    Jepsen, Niels; Eg Nielsen, Einar; Deacon, M.

    2005-01-01

    (Salmo salar) in a Danish lowland river. The river has a small population of native salmon, but salmon juveniles from Irish, Scottish and Swedish populations have been stocked and return as adults. A total of 39 salmon were caught by electrofishing and tagged by surgical implantation. A tissue sample......Many stocks of fish consist of mixtures of individuals originating from different populations. This is particularly true for many salmon and trout stocks, where fish of different genetic background are being found in the same rivers and/or lakes due to stocking activities or straying caused...... by increased aquaculture activities. The interpretation of results from studies of survival and behaviour of fish from such “mixed stocks” require information of the genetic background of individual fish. We used genetic analysis combined with radiotelemetry to study upstream migration of Atlantic salmon...

  9. [Linkage to care among new human immunodeficiency virus diagnoses in Spain].

    Science.gov (United States)

    Oliva, Jesús; Malo, Carmen; Fernández, Ana; Izquierdo, Ana; Marcos, Henar; Cevallos, Carlos; Castilla, Jesús; García, Rocio; Díez, Mercedes

    2014-03-01

    To describe linkage to care among new HIV diagnoses in Spain; and to estimate factors associated to linkage to care within three months after diagnosis. The distribution of the time elapsing between the date of HIV diagnosis and the date of first determination of CD4 (considered to be the date of linkage to care) was calculated among new HIV diagnoses in 2010 in the seven Autonomous Regions participating, where data on date of CD4 count was available. Linkage to care was considered «correct» if done within three months after diagnosis. Factors associated to correct linkage to care were estimated using logistic regression. A total of 1769 new HIV diagnoses were included. Of them, 83.1% had evidence of linkage to care within a year, and 75.7% were linked within three months after diagnosis. Being an injectable drug user (IDU) was the only factor inversely associated with linkage to care within 3 months (OR = 0.3; 95% CI: 0.2-0.6). In Spain linkage to care after HIV diagnosis is good, but there is still room for improvement, especially among IDUs. Copyright © 2013 Elsevier España, S.L. y Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica. All rights reserved.

  10. Phase-Division-Based Dynamic Optimization of Linkages for Drawing Servo Presses

    Science.gov (United States)

    Zhang, Zhi-Gang; Wang, Li-Ping; Cao, Yan-Ke

    2017-11-01

    Existing linkage-optimization methods are designed for mechanical presses; few can be directly used for servo presses, so development of the servo press is limited. Based on the complementarity of linkage optimization and motion planning, a phase-division-based linkage-optimization model for a drawing servo press is established. Considering the motion-planning principles of a drawing servo press, and taking account of work rating and efficiency, the constraints of the optimization model are constructed. Linkage is optimized in two modes: use of either constant eccentric speed or constant slide speed in the work segments. The performances of optimized linkages are compared with those of a mature linkage SL4-2000A, which is optimized by a traditional method. The results show that the work rating of a drawing servo press equipped with linkages optimized by this new method improved and the root-mean-square torque of the servo motors is reduced by more than 10%. This research provides a promising method for designing energy-saving drawing servo presses with high work ratings.

  11. Are hybrids between Atlantic salmon and brown trout suitable long-term hosts of Gyrodactylus salaris during winter?

    Science.gov (United States)

    Knudsen, R; Henriksen, E H; Gjelland, K Ø; Hansen, H; Hendrichsen, D K; Kristoffersen, R; Olstad, K

    2017-10-01

    The monogenean parasite Gyrodactylus salaris poses serious threats to many Atlantic salmon populations and presents many conservation and management questions/foci and challenges. It is therefore critical to identify potential vectors for infection. To test whether hybrids of native Atlantic salmon (Salmo salar) × brown trout (Salmo trutta) are suitable as reservoir hosts for G. salaris during winter, infected hybrid parr were released into a natural subarctic brook in the autumn. Six months later, 23.9% of the pit-tagged fish were recaptured. During the experimental period, the hybrids had a sixfold increase in mean intensity of G. salaris, while the prevalence decreased from 81% to 35%. There was high interindividual hybrid variability in susceptibility to infections. The maximum infrapopulation growth rate (0.018 day -1 ) of G. salaris throughout the winter was comparable to earlier laboratory experiments at similar temperatures. The results confirm that infrapopulations of G. salaris may reproduce on a hybrid population for several generations at low water temperatures (~1 °C). Wild salmon-trout hybrids are undoubtedly susceptible to G. salaris and represent an important reservoir host for the parasite independent of other co-occurring susceptible hosts. Consequently, these hybrids may pose a serious risk for G. salaris transmission to nearby, uninfected rivers by migratory individuals. © 2017 John Wiley & Sons Ltd.

  12. An extremely sensitive nested PCR-RFLP mitochondrial marker for detection and identification of salmonids in eDNA from water samples

    Directory of Open Access Journals (Sweden)

    Laura Clusa

    2017-02-01

    Full Text Available Background Salmonids are native from the North Hemisphere but have been introduced for aquaculture and sport fishing in the South Hemisphere and inhabit most rivers and lakes in temperate and cold regions worldwide. Five species are included in the Global Invasive Species Database: rainbow trout Oncorhynchus mykiss, Atlantic salmon Salmo salar, brown trout Salmo trutta, brook trout Salvelinus fontinalis, and lake trout Salvelinus namaycush. In contrast, other salmonids are endangered in their native settings. Methods Here we have developed a method to identify salmonid species directly from water samples, focusing on the Iberian Peninsula as a case study. We have designed nested Salmonidae-specific primers within the 16S rDNA region. From these primers and a PCR-RFLP procedure the target species can be unequivocally identified from DNA extracted from water samples. Results The method was validated in aquarium experiments and in the field with water from watersheds with known salmonid populations. Finally, the method was applied to obtain a global view of the Salmonidae community in Nalón River (north coast of Spain. Discussion This new powerful, very sensitive (identifying the species down to 10 pg DNA/ml water and economical tool can be applied for monitoring the presence of salmonids in a variety of situations, from checking upstream colonization after removal of river barriers to monitoring potential escapes from fish farms.

  13. Topography of the Flattest Surface on Earth: using ICESAT, GPS, and MISR to Measure Salt Surface Topography on Salar de Uyuni, Bolivia

    Science.gov (United States)

    Comstock, Robert L.; Bills, Bruce G.

    2004-01-01

    Salt flats are aptly named: they are composed largely of salt, and are maintained as nearly equipotential surfaces via frequent flooding. The salar de Uyuni, on the Altiplano in southwestern Bolivia, is the largest salt flat on Earth, with an area of 9,800 sq km. Except for a few bedrock islands, it has less than 40 cm of relief. The upper-most salt unit averages 5 m thick and contains 50 cu km of nearly pure halite. It includes most of the salt that was in solution in paleolake Minchin, which attained a maximum area of 60,000 sq km and a maximum depth of 150 m, roughly 15 kyr ago. Despite approx. 10 m of differential isostatic rebound since deposition, the salar surface has been actively maintained as an extraordinarily flat and smooth surface by annual flooding during the rainy season. We have used the strong optical absorption properties of water in the visible band to map spatial variations in water depth during a time when the salar was flooded. As water depth increases, the initially pure white surface appears both darker and bluer. We utilized MISR images taken during the interval from April to November 2001. The red and infra-red bands (672 and 867 nm wavelength) were most useful since the water depth is small and the absorption at those wavelengths is quite strong. Nadir pointed MISR images have 275 m spatial resolution. To aid in our evaluation of water depth variations over the saiar surface, we utilized two sources of direct topographic measurements: several ICESAT altimetry tracks cross the area, and a 40x50 km GPS grid was surveyed to calibrate ICESAT. A difficulty in using these data types is that both give salt surface elevations relative to the ellipsoid, whereas the water surface will, in the absence of wind or tidal disturbances, follow an equipotential surface. Geoid height is not known to the required accuracy of a few cm in the central Andes. As a result, before comparing optical absorption from MISR to salt surface topography from GPS or

  14. Blood ph and mortality of rainbow trout (Salmo gairdnerii) and sockeye salmon (Oncorhynchus nerka)

    Energy Technology Data Exchange (ETDEWEB)

    Jonas, R E.E.; Sehdev, H S; Tomlinson, N

    1972-01-01

    Rainbow trout (Salmo gairdnerii) under light anaesthesia with MS 222 (Tricaine methanesulphonate) died when their blood pH was lowered into the range of 6.8 to 6.9 by injection of either lactic acid or hydrochloric acid. When injection of the same quantities of either acid did not lower the blood pH into this range, fatalities did not result (one exception in 56 fish injected). The injection of much larger quantities of lactate of chloride ions in the form of sodium salts did not cause fatalities. Very limited date for sockeye salmon (Oncorhynchus nerka) suggest a similar association between blood pH and mortality for this species.

  15. Cannibalism in non-native brown trout Salmo trutta and rainbow trout Oncorhynchus mykiss stream-dwelling populations.

    Science.gov (United States)

    Musseau, C; Vincenzi, S; Jesenšek, D; Crivelli, A J

    2017-12-01

    Introduced and allopatric populations of brown trout Salmo trutta and rainbow trout Oncorhynchus mykiss were sampled in Slovenia for stable isotope analysis to assess dietary niche shifts through ontogeny and estimate the propensity for cannibalism. Both S. trutta and O. mykiss are cannibals, with higher average relative contribution of conspecific assimilated energy for S. trutta (27·9%) compared with O. mykiss (7·7%). The smallest cannibal was 166 mm in the S. trutta population and 247 mm in the O. mykiss population. © 2017 The Fisheries Society of the British Isles.

  16. Effects of aquaculture researchers' job characteristics on linkage ...

    African Journals Online (AJOL)

    The study examined the effects of researchers' job characteristics on linkage activities in Nigeria due to the fact that many fish farmers have not been properly reached with technologies and the problem of poor fish production has been attributed to the weak linkages existing between research, extension and fish farmers.

  17. Analysis of strontium-90 in the bones of brown trout (Salmo trutta) from Lake Ontario

    International Nuclear Information System (INIS)

    Manos, C.G. Jr.; Kinney, R.M.; Lisk, D.J.

    1993-01-01

    Radionuclides such as Sr-90, mainly from liquid effluent releases from nuclear power generating facilities, can contaminate water and biota. Lake Ontario ultimately receives the outflow from each of the other Great Lakes. In the work reported, brown trout (Salmo trutta) were captured from Lake Ontario and their entire skeletal bone material analyzed for Sr-90. They showed an average concentration of Sr-90 approximately four times greater than control brown trout captured from nearby Cayuga Lake in Central New York State which has no nuclear generating facilities. The results are discussed considering fallout and hydrographic considerations. (author)

  18. Nature–society linkages in the Aral Sea region

    Directory of Open Access Journals (Sweden)

    Kristopher D. White

    2013-01-01

    Full Text Available Central Asia's Aral Sea crisis represents a disaster of monumental proportions, a tragedy for both the region's ecology and its human inhabitants. While the human and natural environments had operated in a sustainable co-joined system for millennia, Tsarist Russian expansion into Central Asia, followed by Soviet expansion of both the cotton industry and unsustainable irrigation practices to anchor it spelled doom for the Aral Sea. Today, many of the political and economic stimuli for such misguided practices continue, as do the continued retreat of the Sea and the proliferation of poor human health. The Aral Sea crisis has received ample scholarly attention, though somewhat surprising is a relative dearth of research explicitly investigating the nature, variety, and directionality of nature–society linkages today within the region. The purpose of this paper is to elucidate the contemporary nature–society linkages operating within the Aral Sea region of Central Asia. Historical nexuses will provide necessary background, and the linkages operating currently within the spheres of regional economy, human health, and political considerations will be detailed. Couching the current crisis within the framework of coupled human–environment system contexts reveals a region in which these linkages are largely inextricable. This paper concludes with a call for a reconsideration of the nature-society linkages and a greater emphasis placed on the local region's ecological and social sustainability.

  19. Intragroup Emotions: Physiological Linkage and Social Presence.

    Science.gov (United States)

    Järvelä, Simo; Kätsyri, Jari; Ravaja, Niklas; Chanel, Guillaume; Henttonen, Pentti

    2016-01-01

    We investigated how technologically mediating two different components of emotion-communicative expression and physiological state-to group members affects physiological linkage and self-reported feelings in a small group during video viewing. In different conditions the availability of second screen text chat (communicative expression) and visualization of group level physiological heart rates and their dyadic linkage (physiology) was varied. Within this four person group two participants formed a physically co-located dyad and the other two were individually situated in two separate rooms. We found that text chat always increased heart rate synchrony but HR visualization only with non-co-located dyads. We also found that physiological linkage was strongly connected to self-reported social presence. The results encourage further exploration of the possibilities of sharing group member's physiological components of emotion by technological means to enhance mediated communication and strengthen social presence.

  20. A high-density SNP linkage scan with 142 combined subtype ADHD sib pairs identifies linkage regions on chromosomes 9 and 16.

    Science.gov (United States)

    Asherson, P; Zhou, K; Anney, R J L; Franke, B; Buitelaar, J; Ebstein, R; Gill, M; Altink, M; Arnold, R; Boer, F; Brookes, K; Buschgens, C; Butler, L; Cambell, D; Chen, W; Christiansen, H; Feldman, L; Fleischman, K; Fliers, E; Howe-Forbes, R; Goldfarb, A; Heise, A; Gabriëls, I; Johansson, L; Lubetzki, I; Marco, R; Medad, S; Minderaa, R; Mulas, F; Müller, U; Mulligan, A; Neale, B; Rijsdijk, F; Rabin, K; Rommelse, N; Sethna, V; Sorohan, J; Uebel, H; Psychogiou, L; Weeks, A; Barrett, R; Xu, X; Banaschewski, T; Sonuga-Barke, E; Eisenberg, J; Manor, I; Miranda, A; Oades, R D; Roeyers, H; Rothenberger, A; Sergeant, J; Steinhausen, H-C; Taylor, E; Thompson, M; Faraone, S V

    2008-05-01

    As part of the International Multi-centre ADHD Genetics project we completed an affected sibling pair study of 142 narrowly defined Diagnostic and Statistical Manual of Mental Disorders, fourth edition combined type attention deficit hyperactivity disorder (ADHD) proband-sibling pairs. No linkage was observed on the most established ADHD-linked genomic regions of 5p and 17p. We found suggestive linkage signals on chromosomes 9 and 16, respectively, with the highest multipoint nonparametric linkage signal on chromosome 16q23 at 99 cM (log of the odds, LOD=3.1) overlapping data published from the previous UCLA (University of California, Los Angeles) (LOD>1, approximately 95 cM) and Dutch (LOD>1, approximately 100 cM) studies. The second highest peak in this study was on chromosome 9q22 at 90 cM (LOD=2.13); both the previous UCLA and German studies also found some evidence of linkage at almost the same location (UCLA LOD=1.45 at 93 cM; German LOD=0.68 at 100 cM). The overlap of these two main peaks with previous findings suggests that loci linked to ADHD may lie within these regions. Meta-analysis or reanalysis of the raw data of all the available ADHD linkage scan data may help to clarify whether these represent true linked loci.

  1. Asian Financial Linkages: The Case of Japan

    OpenAIRE

    Fialová, Anežka

    2014-01-01

    This work reviews the topic of international financial linkages, including theoretical definitions and the main methodological approaches of the empirical measurement based on vector autoregressive models. One of the approaches, the Spillover Index methodology based on Diebold & Yilmaz (2009), is then used to analyze the developments of financial linkages of the Japanese stock market in the period from 1995 to 2012. The attention is paid both to the relations with western developed economies ...

  2. Efficacité d'un exutoire de dévalaison pour smolts de saumon atlantique (Salmo salar L. et comportement des poissons au niveau de l'aménagement hydroélectrique de Bedous sur le gave d'Aspe étudiés par la technique de marquage-recapture et par radiotélémétrie

    Directory of Open Access Journals (Sweden)

    CHANSEAU M.

    1999-04-01

    Full Text Available Deux expérimentations ont été conduites en 1995 et 1998 au niveau de la prise d'eau de l'aménagement hydroélectrique de Bedous sur le Gave d'Aspe afin de tester l'efficacité d'un exutoire de dévalaison pour smolts de saumon atlantique (Salmo salar L.. Le dispositif de dévalaison est situé en rive droite à proximité immédiate du plan des grilles. Le débit moyen alimentant l'exutoire a varié au cours de l'étude de 0,4 m3/s à 1,2 m3/s ce qui correspond à 1,6 % à 4,3 % du débit turbiné. Lefficacité du dispositif a été évaluée grâce à la technique de marquage-recapture. Le comportement des smolts dans le canal d'amenée a été suivi par radiotélémétrie. L'efficacité de l'exutoire (moyenne : 17 % s'est révélée très faible en 1995 â cause de conditions hydrauliques défavorables. Un mur déflecteur a été mis en place en 1997 afin de modifier l'écoulement dans le canal et améliorer le guidage des poissons vers l'entrée du dispositif de dévalaison. L'efficacité de l'exutoire est passée à 55 %. Le comportement des poissons à l'amont immédiat des grilles de prise d'eau est très dépendant des conditions hydrodynamiques dans le canal d'amenée. L'efficacité de l'exutoire semble croître avec la longueur des poissons, la proportion des classes de taille inférieures à 19 cm étant plus faible sur les poissons piégés que sur les poissons lâchés. Cette sélection est très certainement liée à l'espacement relativement important des barreaux des grilles de la prise d'eau (30 mm qui malgré le courant tangentiel au plan de grilles demeurent plus perméables aux individus les plus petits. L'éclairage de l'entrée de l'exutoire ne paraît pas avoir d'influence sur les déplacements des poissons radiomarqués dans le canal d'amenée, le facteur hydraulique étant prépondérant. Il modifie cependant les rythmes de passage des poissons par l'exutoire.

  3. Nance-Horan syndrome: linkage analysis in a family from The Netherlands

    NARCIS (Netherlands)

    Bergen, A. A.; ten Brink, J.; Schuurman, E. J.; Bleeker-Wagemakers, E. M.

    1994-01-01

    Linkage analysis was carried out in a Dutch family with Nance-Horan (NH) syndrome. Close linkage without recombination between NH and the Xp loci DXS207, DXS43, and DXS365 (zmax = 3.23) was observed. Multipoint linkage analysis and the analysis of recombinations in multiple informative meioses

  4. Validation of an instrument to measure inter-organisational linkages in general practice.

    Science.gov (United States)

    Amoroso, Cheryl; Proudfoot, Judith; Bubner, Tanya; Jayasinghe, Upali W; Holton, Christine; Winstanley, Julie; Beilby, Justin; Harris, Mark F

    2007-12-03

    Linkages between general medical practices and external services are important for high quality chronic disease care. The purpose of this research is to describe the development, evaluation and use of a brief tool that measures the comprehensiveness and quality of a general practice's linkages with external providers for the management of patients with chronic disease. In this study, clinical linkages are defined as the communication, support, and referral arrangements between services for the care and assistance of patients with chronic disease. An interview to measure surgery-level (rather than individual clinician-level) clinical linkages was developed, piloted, reviewed, and evaluated with 97 Australian general practices. Two validated survey instruments were posted to patients, and a survey of locally available services was developed and posted to participating Divisions of General Practice (support organisations). Hypotheses regarding internal validity, association with local services, and patient satisfaction were tested using factor analysis, logistic regression and multilevel regression models. The resulting General Practice Clinical Linkages Interview (GP-CLI) is a nine-item tool with three underlying factors: referral and advice linkages, shared care and care planning linkages, and community access and awareness linkages. Local availability of chronic disease services has no affect on the comprehensiveness of services with which practices link, however, comprehensiveness of clinical linkages has an association with patient assessment of access, receptionist services, and of continuity of care in their general practice. The GP-CLI may be useful to researchers examining comparable health care systems for measuring the comprehensiveness and quality of linkages at a general practice-level with related services, possessing both internal and external validity. The tool can be used with large samples exploring the impact, outcomes, and facilitators of high

  5. Validation of an instrument to measure inter-organisational linkages in general practice

    Directory of Open Access Journals (Sweden)

    Cheryl Amoroso

    2007-11-01

    Full Text Available Purpose: Linkages between general medical practices and external services are important for high quality chronic disease care. The purpose of this research is to describe the development, evaluation and use of a brief tool that measures the comprehensiveness and quality of a general practice’s linkages with external providers for the management of patients with chronic disease. In this study, clinical linkages are defined as the communication, support, and referral arrangements between services for the care and assistance of patients with chronic disease. Methods: An interview to measure surgery-level (rather than individual clinician-level clinical linkages was developed, piloted, reviewed, and evaluated with 97 Australian general practices. Two validated survey instruments were posted to patients, and a survey of locally available services was developed and posted to participating Divisions of General Practice (support organisations. Hypotheses regarding internal validity, association with local services, and patient satisfaction were tested using factor analysis, logistic regression and multilevel regression models. Results: The resulting General Practice Clinical Linkages Interview (GP-CLI is a nine-item tool with three underlying factors: referral and advice linkages, shared care and care planning linkages, and community access and awareness linkages. Local availability of chronic disease services has no affect on the comprehensiveness of services with which practices link, however comprehensiveness of clinical linkages has an association with patient assessment of access, receptionist services, and of continuity of care in their general practice. Conclusions: The GP-CLI may be useful to researchers examining comparable health care systems for measuring the comprehensiveness and quality of linkages at a general practice-level with related services, possessing both internal and external validity. The tool can be used with large samples

  6. The Barley Chromosome 5 Linkage Map

    DEFF Research Database (Denmark)

    Jensen, J.; Jørgensen, Jørgen Helms

    1975-01-01

    The distances between nine loci on barley chromosome 5 have been studied in five two-point tests, three three-point tests, and one four-point test. Our previous chromosome 5 linkage map, which contained eleven loci mapped from literature data (Jensen and Jørgensen 1975), is extended with four loci......-position is fixed on the map by a locus (necl), which has a good marker gene located centrally in the linkage group. The positions of the other loci are their distances in centimorgans from the 0-position; loci in the direction of the short chromosome arm are assigned positive values and those...

  7. Clause linkage in Ket

    NARCIS (Netherlands)

    Nefedov, Andrey

    2015-01-01

    This work provides a typologically oriented description of clause linkage strategies in Ket, a highly endangered language spoken in Central Siberia. It is now the only surviving member of the Yeniseian language family with the last remaining speakers residing in the north of Russia’s Krasnoyarsk

  8. Intragroup emotions: physiological linkage and social presence

    Directory of Open Access Journals (Sweden)

    Simo eJärvelä

    2016-02-01

    Full Text Available We investigated how technologically mediating two different components of emotion – communicative expression and physiological state – to group members affects physiological linkage and self-reported feelings in a small group during video viewing. In different conditions the availability of second screen text chat (communicative expression and visualization of group level physiological heart rates and their dyadic linkage (physiology was varied. Within this four person group two participants formed a physically co-located dyad and the other two were individually situated in two separate rooms. We found that text chat always increased heart rate synchrony but HR visualization only with non-co-located dyads. We also found that physiological linkage was strongly connected to self-reported social presence. The results encourage further exploration of the possibilities of sharing group member’s physiological components of emotion by technological means to enhance mediated communication and strengthen social presence.

  9. Intragroup Emotions: Physiological Linkage and Social Presence

    Science.gov (United States)

    Järvelä, Simo; Kätsyri, Jari; Ravaja, Niklas; Chanel, Guillaume; Henttonen, Pentti

    2016-01-01

    We investigated how technologically mediating two different components of emotion—communicative expression and physiological state—to group members affects physiological linkage and self-reported feelings in a small group during video viewing. In different conditions the availability of second screen text chat (communicative expression) and visualization of group level physiological heart rates and their dyadic linkage (physiology) was varied. Within this four person group two participants formed a physically co-located dyad and the other two were individually situated in two separate rooms. We found that text chat always increased heart rate synchrony but HR visualization only with non-co-located dyads. We also found that physiological linkage was strongly connected to self-reported social presence. The results encourage further exploration of the possibilities of sharing group member's physiological components of emotion by technological means to enhance mediated communication and strengthen social presence. PMID:26903913

  10. Estimation of sodium uptake through the gill of the rainbow trout Salmo gairdneri

    Energy Technology Data Exchange (ETDEWEB)

    Gardaire, E.; Avella, M.; Isaia, J.; Bornancin, M.; Mayer-Gostan, N.

    1985-01-01

    Sodium exchanges through the gill epithelia were estimated in the rainbow trout, Salmo gairdneri, using the perfused head technique. The head tissues accumulate radioactivity. In addition there exists an extrabranchial entry of sodium, which is 20 times smaller than the branchial one. The study of the evolution of venous and arterial sodium specific activities as a function of time is necessary before flux measurements are achieved. Contrary to previous studies, an uptake at the primary lamella level is demonstrated. Uptake of sodium through the secondary lamellae can be measured rapidly while at least 30 min are needed for measurement of uptake through the primary lamellae. Chloride cells of the primary lamellae contribute to about 20% of the total sodium uptake.

  11. Identifying and Mapping Linkages between Actors in the Climate ...

    African Journals Online (AJOL)

    Promoting innovations in climate change requires innovation partnerships and linkages and also creating an enabling environment for actors. The paper reviewed available information on the identification and mapping of linkages between actors in the climate change innovation system. The findings showed different ...

  12. Solid-Phase Synthesis of RNA Analogs Containing Phosphorodithioate Linkages.

    Science.gov (United States)

    Yang, Xianbin

    2017-09-18

    The oligoribonucleotide phosphorodithioate (PS2-RNA) modification uses two sulfur atoms to replace two non-bridging oxygen atoms at an internucleotide phosphorodiester backbone linkage. Like a natural phosphodiester RNA backbone linkage, a PS2-modified backbone linkage is achiral at phosphorus. PS2-RNAs are highly stable to nucleases and several in vitro assays have demonstrated their biological activity. For example, PS2-RNAs silenced mRNA in vitro and bound to protein targets in the form of PS2-aptamers (thioaptamers). Thus, the interest in and promise of PS2-RNAs has drawn attention to synthesizing, isolating, and characterizing these compounds. RNA-thiophosphoramidite monomers are commercially available from AM Biotechnologies and this unit describes an effective methodology for solid-phase synthesis, deprotection, and purification of RNAs having PS2 internucleotide linkages. © 2017 by John Wiley & Sons, Inc. Copyright © 2017 John Wiley & Sons, Inc.

  13. Effects of Worldwide Population Subdivision on ALDH2 Linkage Disequilibrium

    OpenAIRE

    Peterson, Raymond J.; Goldman, David; Long, Jeffrey C.

    1999-01-01

    The effect of human population subdivision on linkage disequilibrium has previously been studied for unlinked genes. However, no study has focused on closely linked polymorphisms or formally partitioned linkage disequilibrium within and among worldwide populations. With an emphasis on population subdivision, the goal of this paper is to investigate the causes of linkage disequilibrium in ALDH2, the gene that encodes aldehyde dehydrogenase 2. Haplotypes for 756 people from 17 populations acros...

  14. Data Linkage in VET Research: Opportunities, Challenges and Principles. Discussion Paper

    Science.gov (United States)

    Osborne, Kristen; Fowler, Craig; Circelli, Michelle

    2018-01-01

    This discussion paper explores the possibilities and risks that data linkage presents for the vocational education and training (VET) sector. Along with a broad overview of the nature of data linkage, it highlights possible applications for data linkage in the VET sector and examines the key challenges associated with its use. A number of case…

  15. Gene cloning and mRNA expression of glutamate dehydrogenase in the liver, brain and intestine of the swamp eel, Monopterus albus, exposed to freshwater, terrestrial conditions, environmental ammonia or salinity stress

    Directory of Open Access Journals (Sweden)

    C Y Toh

    2011-12-01

    Full Text Available The swamp eel, Monopterus albus, is an obligatory air-breathing teleost which can survive long period of emersion, has high environmental and tissue ammonia tolerance, and acclimate from fresh to brackish water. This study was undertaken to clone and sequence gdh expressed in the liver, intestine and brain of M. albus, to verify whether more than one form of gdh were expressed, and to examine the gdh mRNA expressions in these three organs in fish exposed to various adverse conditions using quantitative real-time PCR. Only one gdh gene sequence, consisted of a 133 bp 5’ UTR, a CDS region spanning 1629 bp and a 3’ UTR of approximately 717 bp, was obtained from the liver, intestine and brain of M. albus. The translated Gdh amino acid sequence from the liver of M. albus had 542 residues and was confirmed to be Gdh1a. It had sequence identity of >90% with Oncorhynchus mykiss Gdh1a, Salmo salar Gdh1a1, Bostrychus sinensis Gdh1a and Tribolodon hakonensis Gdh1a, and formed a monophyletic clade with B. sinensis Gdh1a, Tetraodon nigroviridis Gdh1a, Chaenocephalus aceratus Gdh1a, Salmo salar Gdh1a1 and Gdh1a2 and O. mykiss Gdh1a. An increase in mRNA expression of gdh1a could be essential for increased glutamate production in support of increases in glutamine synthesis under certain environmental condition. Indeed, exposure of M. albus to 1 day of terrestrial conditions or 75 mmol l-1 NH4Cl, but not brackish water, resulted in a significant increase in gdh1a mRNA expression in the liver. However, exposure to brackish water, but not terrestrial conditions or 75 mmol l-1 NH4Cl, lead to a significant increase in the intestinal mRNA expression of gdh1a. By contrast, all the three experimental conditions had no significant effects on the mRNA expression of gdh1a in the brain of M. albus. Our results indicate for the first time that gdh mRNA expression was differentially up-regulated in the liver and intestine of M. albus, in responses to ammonia toxicity and

  16. Statistical methods for estimating normal blood chemistry ranges and variance in rainbow trout (Salmo gairdneri), Shasta Strain

    Science.gov (United States)

    Wedemeyer, Gary A.; Nelson, Nancy C.

    1975-01-01

    Gaussian and nonparametric (percentile estimate and tolerance interval) statistical methods were used to estimate normal ranges for blood chemistry (bicarbonate, bilirubin, calcium, hematocrit, hemoglobin, magnesium, mean cell hemoglobin concentration, osmolality, inorganic phosphorus, and pH for juvenile rainbow (Salmo gairdneri, Shasta strain) trout held under defined environmental conditions. The percentile estimate and Gaussian methods gave similar normal ranges, whereas the tolerance interval method gave consistently wider ranges for all blood variables except hemoglobin. If the underlying frequency distribution is unknown, the percentile estimate procedure would be the method of choice.

  17. Genetic detection of sex-specific dispersal in historical and contemporary populations of anadromous brown trout Salmo trutta

    DEFF Research Database (Denmark)

    Bekkevold, Dorte; Hansen, Michael Møller; Mensberg, Karen-Lise Dons

    2004-01-01

    The study of sex-biased dispersal has attracted considerable attention in birds and mammals, but less in other taxa, including fishes. We analysed sex-specific dispersal in historical (1910s and 1950s) and contemporary (1990s) samples of anadromous brown trout Salmo trutta. We tested the hypothesis...... that dispersal is unbiased using information from microsatellite DNA and applying an assignment index for 11 temporally and spatially separated samples. Our results are most consistent with brown trout dispersal being male biased, and provide no evidence of female bias. We found no evidence that dispersal...

  18. Parasitofauna study of the brown trout, Salmo trutta (Pisces, Teleostei from Corsica (Mediterranean island rivers

    Directory of Open Access Journals (Sweden)

    Quilichini Y.

    2007-09-01

    Full Text Available Corsica is a mediterranean island characterised by a great number of rivers. Salmonides are the main fishes which populate these rivers. Very appreciated by fishermen, Salmonides are represented by three species in the insular hydrographical network, among which an autochthonous species, the brown trout (Salmo trutta. In the present work, we have analysed the parasitofauna of this species. According to our knowledge, this research has never been carried out in Corsica. In a first step, we drew up an inventory of the parasites found in this freshwater fish. In a second step, we studied the differences which appeared in the composition of parasite communities of this species.

  19. Arctic-midlatitude weather linkages in North America

    Science.gov (United States)

    Overland, James E.; Wang, Muyin

    2018-06-01

    There is intense public interest in whether major Arctic changes can and will impact midlatitude weather such as cold air outbreaks on the central and east side of continents. Although there is progress in linkage research for eastern Asia, a clear gap is conformation for North America. We show two stationary temperature/geopotential height patterns where warmer Arctic temperatures have reinforced existing tropospheric jet stream wave amplitudes over North America: a Greenland/Baffin Block pattern during December 2010 and an Alaska Ridge pattern during December 2017. Even with continuing Arctic warming over the past decade, other recent eastern US winter months were less susceptible for an Arctic linkage: the jet stream was represented by either zonal flow, progressive weather systems, or unfavorable phasing of the long wave pattern. The present analysis lays the scientific controversy over the validity of linkages to the inherent intermittency of jet stream dynamics, which provides only an occasional bridge between Arctic thermodynamic forcing and extended midlatitude weather events.

  20. A microsatellite linkage map of Drosophila mojavensis

    Directory of Open Access Journals (Sweden)

    Schully Sheri

    2004-05-01

    Full Text Available Abstract Background Drosophila mojavensis has been a model system for genetic studies of ecological adaptation and speciation. However, despite its use for over half a century, no linkage map has been produced for this species or its close relatives. Results We have developed and mapped 90 microsatellites in D. mojavensis, and we present a detailed recombinational linkage map of 34 of these microsatellites. A slight excess of repetitive sequence was observed on the X-chromosome relative to the autosomes, and the linkage groups have a greater recombinational length than the homologous D. melanogaster chromosome arms. We also confirmed the conservation of Muller's elements in 23 sequences between D. melanogaster and D. mojavensis. Conclusions The microsatellite primer sequences and localizations are presented here and made available to the public. This map will facilitate future quantitative trait locus mapping studies of phenotypes involved in adaptation or reproductive isolation using this species.

  1. High-frequency stock linkage and multi-dimensional stationary processes

    Science.gov (United States)

    Wang, Xi; Bao, Si; Chen, Jingchao

    2017-02-01

    In recent years, China's stock market has experienced dramatic fluctuations; in particular, in the second half of 2014 and 2015, the market rose sharply and fell quickly. Many classical financial phenomena, such as stock plate linkage, appeared repeatedly during this period. In general, these phenomena have usually been studied using daily-level data or minute-level data. Our paper focuses on the linkage phenomenon in Chinese stock 5-second-level data during this extremely volatile period. The method used to select the linkage points and the arbitrage strategy are both based on multi-dimensional stationary processes. A new program method for testing the multi-dimensional stationary process is proposed in our paper, and the detailed program is presented in the paper's appendix. Because of the existence of the stationary process, the strategy's logarithmic cumulative average return will converge under the condition of the strong ergodic theorem, and this ensures the effectiveness of the stocks' linkage points and the more stable statistical arbitrage strategy.

  2. Development of the retinotopic organization in Salmo gairdneri

    International Nuclear Information System (INIS)

    Pinganaud, G.

    1987-01-01

    The progression of the retinotopic organization in the optic nerve projections to the contralateral thalamus and tectum was studied in Salmo gairdneri from hatching stage to 3 month old stage. After quadratic lesions of the temporal, dorsal, nasal, or ventral retina, the animals were separated in two groups: one used for Fink and Heimer method or electron microscopic observation and the other one for radioautography after injection in the operated eye of [ 14 C] or [ 3 H]proline. The analysis of the projections of each retinal quadrant revealed: (1) Projections to thalamus and pretectum are ignorganized and appear progressively during development. On the contrary in tectum and corpus geniculatum, the visual projections are retinotopically organized since hatching. (2) In the whole retino-tectal system, two subsystems develop differently: the naso-ventral retina reaches precociously its permanent target (the posterior tectum), the temporo-dorsal part of the retina links to the anterior tectum and shifts laterally during the first month after hatching, from medial to antero-lateral for temporal projections. The shifting of projections is correlated with development of the medial fascicle of the optic tract. So it appears that the pathways play an important role in the spatio-temporal ordered pattern of terminations of retinal fibers on the tectal surface during development. (author)

  3. Problems Threatening the Tigris Trout (Salmo tigridis Turan, Kottelat & Bektaş, 2011 Stock in Çatak Stream and Some Recommendations

    Directory of Open Access Journals (Sweden)

    Mustafa AKKUŞ

    2017-12-01

    Full Text Available This study was carried out to reveal the problems threatening Salmo tigridis stock inhabited in Çatak Stream and to offer some solutions to overcome these problems. Çatak is the largest stream of the region and located at 81 km southern of the Van city center. Salmo tigridis, which is only distributed in Çatak and Bahçesaray streams, faces the danger of extinction. In this study, it was observed that sand-graveling activities at Çatak Stream muddied the stream and destroyed appropriate reproduction habitats. Another problem is that Çatak Stream's over-destruction of vegetation in the catchment basin increases flood risk and flood-related sudden flow increases. In addition, it was determined that studies carried out for river improvement and flood control disturbed the natural flow regime of the stream, leading to deterioration in the base and coastal structure. Another threat is the rainbow trout (Oncorhynchus mykiss that escape from fish farms. Catching with prohibited methods and fishing gears is also a problem that threatens the future of native trout stock in the stream. With this study, the problems that threaten the tigris trout stock in Çatak Stream were identified and some proposals were presented.

  4. Autosomal dominant distal myopathy: Linkage to chromosome 14

    Energy Technology Data Exchange (ETDEWEB)

    Laing, N.G.; Laing, B.A.; Wilton, S.D.; Dorosz, S.; Mastaglia, F.L.; Kakulas, B.A. [Australian Neuromuscular Research Institute, Perth (Australia); Robbins, P.; Meredith, C.; Honeyman, K.; Kozman, H.

    1995-02-01

    We have studied a family segregating a form of autosomal dominant distal myopathy (MIM 160500) and containing nine living affected individuals. The myopathy in this family is closest in clinical phenotype to that first described by Gowers in 1902. A search for linkage was conducted using microsatellite, VNTR, and RFLP markers. In total, 92 markers on all 22 autosomes were run. Positive linkage was obtained with 14 of 15 markers tested on chromosome 14, with little indication of linkage elsewhere in the genome. Maximum two-point LOD scores of 2.60 at recombination fraction .00 were obtained for the markers MYH7 and D14S64 - the family structure precludes a two-point LOD score {ge} 3. Recombinations with D14S72 and D14S49 indicate that this distal myopathy locus, MPD1, should lie between these markers. A multipoint analysis assuming 100% penetrance and using the markers D14S72, D14S50, MYH7, D14S64, D14S54, and D14S49 gave a LOD score of exactly 3 at MYH7. Analysis at a penetrance of 80% gave a LOD score of 2.8 at this marker. This probable localization of a gene for distal myopathy, MPD1, on chromosome 14 should allow other investigators studying distal myopathy families to test this region for linkage in other types of the disease, to confirm linkage or to demonstrate the likely genetic heterogeneity. 24 refs., 3 figs., 1 tab.

  5. Sneaker Males Affect Fighter Male Body Size and Sexual Size Dimorphism in Salmon.

    Science.gov (United States)

    Weir, Laura K; Kindsvater, Holly K; Young, Kyle A; Reynolds, John D

    2016-08-01

    Large male body size is typically favored by directional sexual selection through competition for mates. However, alternative male life-history phenotypes, such as "sneakers," should decrease the strength of sexual selection acting on body size of large "fighter" males. We tested this prediction with salmon species; in southern populations, where sneakers are common, fighter males should be smaller than in northern populations, where sneakers are rare, leading to geographical clines in sexual size dimorphism (SSD). Consistent with our prediction, fighter male body size and SSD (fighter male∶female size) increase with latitude in species with sneaker males (Atlantic salmon Salmo salar and masu salmon Oncorhynchus masou) but not in species without sneakers (chum salmon Oncorhynchus keta and pink salmon Oncorhynchus gorbuscha). This is the first evidence that sneaker males affect SSD across populations and species, and it suggests that alternative male mating strategies may shape the evolution of body size.

  6. A real-time polymerase chain reaction method for the identification of four commercially important salmon and trout species.

    Science.gov (United States)

    Feng, Junli; Wu, Zhigang; Xie, Xiao; Dai, Zhiyuan; Liu, Shasha

    2017-01-01

    A duplex quantitative real-time PCR (qPCR) assay was developed for rapid and accurate identification of four commercially important salmon and trout species (Oncorhynchus keta, Oncorhynchus nerka, Oncorhynchus mykiss, and Salmo salar) commonly used for production process of fish in China. The assays targeting the mitochondrial control region (CR) and 16S rRNA gene were able to simultaneously discriminate four target species and the family Salmonidae from processed as well as fresh fish. The qPCR efficiency of each reaction was calculated according to the standard curve, and the method was validated by amplification DNA extracted from single or artificial mixtures prepared with the reference salmon and trout species. Testing of 11 commercial salmon and trout products by the established qPCR assay demonstrated that it was really a useful and academic technique to identify four commercially important salmon and trout species.

  7. Historical occurrence and extinction of Atlantic salmon in the River Elbe from the fourteenth to the twentieth centuries

    Directory of Open Access Journals (Sweden)

    Andreska J.

    2015-03-01

    Full Text Available Data on the occurrence, biology, and historical background of the Atlantic salmon, Salmo salar L., (Pisces, Salmoniformes in the Elbe river basin (Europe, North Sea drainage area with a focus on Bohemian territory (Central Europe from the fourteenth to twentieth centuries are summarized in this paper. Historical methods of salmon fishing in Central Europe and historical legal protection of salmon in Bohemia are presented. The salmon is a model example of species which was extirpated as a result of anthropogenic changes in the landscape and rivers in some water systems. The human activities, such as stream bed regulation, dam system construction, other migration barriers, water pollution, fisheries exploitation, that led to the extirpation of Atlantic salmon in the Elbe river basin (are discussed. The last sporadic migrating native salmon were registered in the Bohemian section of the Elbe river basin in the mid twentieth century.

  8. Microhabitat selection of Gyrodactylus salaris  with reference to susceptibility status of the salmonid host

    DEFF Research Database (Denmark)

    Heinecke, Rasmus Demuth; Buchmann, Kurt

    Five strains of salmon Salmo salar and a strain of Danish rainbow trout Oncorhynchus mykiss were experimentally infected with the ectoparasite Gyrodactylus salaris (Lærdalselva strain, Norway). All fish were hatchery-reared and the genetic origins were from the East Atlantic: River Conon (Scotland......), Storå (western Denmark) and Ätran (western Sweden) and from the Baltic: River Lule and Ume (Sweden). The rainbow trout used were from a Danish fish farm. Three replicate aquaria infested with G. salaris were established containing 10 fish of every strain. The numbers of parasites were assessed...... on anesthetized fish once a week from week 0 to week 8 and concurrently the location of every parasite on each of twelve regions on the fish was recorded. The mean abundance of G. salaris steadily increased on the East Atlantic Conon, Storå and Ätran strains until the end of the experiment. The mean abundance...

  9. Antibodies recognizing both IgM isotypes in Atlantic salmon

    DEFF Research Database (Denmark)

    Hedfors, Ida Aagård; Bakke, Hege; Skjødt, Karsten

    2012-01-01

    these molecules. The present study aimed at identifying tools to separate IgM positive (IgM(+)) B cells from IgM negative (IgM(-)) non-B cell populations using flow cytometry. Several monoclonal antibodies (mAbs), and one polyclonal antibody (pAb) to both rainbow trout (Oncorhynchus mykiss) and Atlantic salmon...... (Salmo salar) IgM, either commercially available or locally produced were tested for their recognition of Atlantic salmon IgM(+) cells. Leukocytes were isolated from peripheral blood (PB), spleen (S) and head kidney (HK) and stained with all mAbs and the pAb, to possibly verify the approximate number...... of IgM(+) cells in the respective tissues in salmon. To our surprise, this seemingly simple task did not reveal similar staining patterns for all antibodies as expected, but rather large differences in the number of positively stained cells were discovered. In short, positively stained cells by each...

  10. Construction of a reference genetic linkage map for carnation (Dianthus caryophyllus L.).

    Science.gov (United States)

    Yagi, Masafumi; Yamamoto, Toshiya; Isobe, Sachiko; Hirakawa, Hideki; Tabata, Satoshi; Tanase, Koji; Yamaguchi, Hiroyasu; Onozaki, Takashi

    2013-10-26

    Genetic linkage maps are important tools for many genetic applications including mapping of quantitative trait loci (QTLs), identifying DNA markers for fingerprinting, and map-based gene cloning. Carnation (Dianthus caryophyllus L.) is an important ornamental flower worldwide. We previously reported a random amplified polymorphic DNA (RAPD)-based genetic linkage map derived from Dianthus capitatus ssp. andrezejowskianus and a simple sequence repeat (SSR)-based genetic linkage map constructed using data from intraspecific F2 populations; however, the number of markers was insufficient, and so the number of linkage groups (LGs) did not coincide with the number of chromosomes (x = 15). Therefore, we aimed to produce a high-density genetic map to improve its usefulness for breeding purposes and genetic research. We improved the SSR-based genetic linkage map using SSR markers derived from a genomic library, expression sequence tags, and RNA-seq data. Linkage analysis revealed that 412 SSR loci (including 234 newly developed SSR loci) could be mapped to 17 linkage groups (LGs) covering 969.6 cM. Comparison of five minor LGs covering less than 50 cM with LGs in our previous RAPD-based genetic map suggested that four LGs could be integrated into two LGs by anchoring common SSR loci. Consequently, the number of LGs corresponded to the number of chromosomes (x = 15). We added 192 new SSRs, eight RAPD, and two sequence-tagged site loci to refine the RAPD-based genetic linkage map, which comprised 15 LGs consisting of 348 loci covering 978.3 cM. The two maps had 125 SSR loci in common, and most of the positions of markers were conserved between them. We identified 635 loci in carnation using the two linkage maps. We also mapped QTLs for two traits (bacterial wilt resistance and anthocyanin pigmentation in the flower) and a phenotypic locus for flower-type by analyzing previously reported genotype and phenotype data. The improved genetic linkage maps and SSR markers developed

  11. Do habitat measurements in the vicinity of Atlantic salmon (Salmo salar) parr matter?

    Czech Academy of Sciences Publication Activity Database

    Mocq, Julien; St-Hilaire, A.; Cunjak, R. A.

    2018-01-01

    Roč. 25, č. 1 (2018), s. 22-30 ISSN 0969-997X Institutional support: RVO:60077344 Keywords : fuzzy logic * habitat measurement methods * habitat model Subject RIV: EH - Ecology, Behaviour OBOR OECD: Marine biology, freshwater biology, limnology Impact factor: 1.327, year: 2016 http://onlinelibrary.wiley.com/doi/10.1111/fme.12262/full

  12. Atlantic Salmon (Salmo salar L. as a Marine Functional Source of Gamma-Tocopherol

    Directory of Open Access Journals (Sweden)

    David Menoyo

    2014-12-01

    Full Text Available Gamma tocopherol (gT exhibits beneficial cardiovascular effects partly due to its anti-inflammatory activity. Important sources of gT are vegetable oils. However, little is known to what extent gT can be transferred into marine animal species such as Atlantic salmon by feeding. Therefore, in this study we have investigated the transfer of dietary gT into salmon. To this end, fish were fed a diet supplemented with 170 ppm gT for 16 weeks whereby alpha tocopherol levels were adjusted to 190 ppm in this and the control diet. Feeding gT-rich diets resulted in a three-fold increase in gT concentrations in the liver and fillet compared to non-gT-supplemented controls. Tissue alpha tocopherol levels were not decreased indicating no antagonistic interaction between gamma- and alpha tocopherol in salmon. The concentration of total omega 3 fatty acids slightly increased in response to dietary gT. Furthermore, dietary gT significantly decreased malondialdehyde in the fillet, determined as a biomarker of lipid peroxidation. In the liver of gT fed salmon we observed an overall down-regulation of genes involved in lipid homeostasis. Additionally, gT improved the antioxidant capacity by up-regulating Gpx4a gene expression in the pyloric caeca. We suggest that Atlantic salmon may provide a marine functional source capable of enriching gT for human consumption.

  13. Temporal stability and rates of post-depositional change in geochemical signatures of brown trout Salmo trutta scales.

    Science.gov (United States)

    Ryan, D; Shephard, S; Kelly, F L

    2016-09-01

    This study investigates temporal stability in the scale microchemistry of brown trout Salmo trutta in feeder streams of a large heterogeneous lake catchment and rates of change after migration into the lake. Laser-ablation inductively coupled plasma mass spectrometry was used to quantify the elemental concentrations of Na, Mg, Mn, Cu, Zn, Ba and Sr in archived (1997-2002) scales of juvenile S. trutta collected from six major feeder streams of Lough Mask, County Mayo, Ireland. Water-element Ca ratios within these streams were determined for the fish sampling period and for a later period (2013-2015). Salmo trutta scale Sr and Ba concentrations were significantly (P < 0·05) correlated with stream water sample Sr:Ca and Ba:Ca ratios respectively from both periods, indicating multi-annual stability in scale and water-elemental signatures. Discriminant analysis of scale chemistries correctly classified 91% of sampled juvenile S. trutta to their stream of origin using a cross-validated classification model. This model was used to test whether assumed post-depositional change in scale element concentrations reduced correct natal stream classification of S. trutta in successive years after migration into Lough Mask. Fish residing in the lake for 1-3 years could be reliably classified to their most likely natal stream, but the probability of correct classification diminished strongly with longer lake residence. Use of scale chemistry to identify natal streams of lake S. trutta should focus on recent migrants, but may not require contemporary water chemistry data. © 2016 The Fisheries Society of the British Isles.

  14. Genetic variation in brown trout Salmo trutta across the Danube, Rhine, and Elbe headwaters: a failure of the phylogeographic paradigm?

    Science.gov (United States)

    Lerceteau-Köhler, Estelle; Schliewen, Ulrich; Kopun, Theodora; Weiss, Steven

    2013-08-26

    Brown trout Salmo trutta have been described in terms of five major mtDNA lineages, four of which correspond to major ocean basins, and one, according to some authors, to a distinct taxon, marbled trout Salmo marmoratus. The Atlantic and Danubian lineages of brown trout meet in a poorly documented contact zone in Central Europe. The natural versus human mediated origin of the Atlantic lineage in the upper Danube is a question of both theoretical and practical importance with respect to conservation management. We provide a comprehensive population genetic analysis of brown trout in the region with the aim of evaluating the geographic distribution and genetic integrity of these two lineages in and around their contact zone. Genetic screening of 114 populations of brown trout across the Danube/Rhine/Elbe catchments revealed a counter-intuitive phylogeographic structure with near fixation of the Atlantic lineage in the sampled portions of the Bavarian Danube. Along the Austrian Danube, phylogeographic informative markers revealed increasing percentages of Danube-specific alleles with downstream distance. Pure Danube lineage populations were restricted to peri-alpine isolates within previously glaciated regions. Both empirical data and simulated hybrid comparisons support that trout in non-glaciated regions north and northeast of the Alps have an admixed origin largely based on natural colonization. In contrast, the presence of Atlantic basin alleles south and southeast of the Alps stems from hatchery introductions and subsequent introgression. Despite extensive stocking of the Atlantic lineage, little evidence of first generation stocked fish or F1 hybrids were found implying that admixture has been established over time. A purely phylogeographic paradigm fails to describe the distribution of genetic lineages of Salmo in Central Europe. The distribution pattern of the Atlantic and Danube lineages is extremely difficult to explain without invoking very strong

  15. Visualization of pairwise and multilocus linkage disequilibrium structure using latent forests.

    Directory of Open Access Journals (Sweden)

    Raphaël Mourad

    Full Text Available Linkage disequilibrium study represents a major issue in statistical genetics as it plays a fundamental role in gene mapping and helps us to learn more about human history. The linkage disequilibrium complex structure makes its exploratory data analysis essential yet challenging. Visualization methods, such as the triangular heat map implemented in Haploview, provide simple and useful tools to help understand complex genetic patterns, but remain insufficient to fully describe them. Probabilistic graphical models have been widely recognized as a powerful formalism allowing a concise and accurate modeling of dependences between variables. In this paper, we propose a method for short-range, long-range and chromosome-wide linkage disequilibrium visualization using forests of hierarchical latent class models. Thanks to its hierarchical nature, our method is shown to provide a compact view of both pairwise and multilocus linkage disequilibrium spatial structures for the geneticist. Besides, a multilocus linkage disequilibrium measure has been designed to evaluate linkage disequilibrium in hierarchy clusters. To learn the proposed model, a new scalable algorithm is presented. It constrains the dependence scope, relying on physical positions, and is able to deal with more than one hundred thousand single nucleotide polymorphisms. The proposed algorithm is fast and does not require phase genotypic data.

  16. Linkage mechanisms in the vertebrate skull: Structure and function of three-dimensional, parallel transmission systems.

    Science.gov (United States)

    Olsen, Aaron M; Westneat, Mark W

    2016-12-01

    Many musculoskeletal systems, including the skulls of birds, fishes, and some lizards consist of interconnected chains of mobile skeletal elements, analogous to linkage mechanisms used in engineering. Biomechanical studies have applied linkage models to a diversity of musculoskeletal systems, with previous applications primarily focusing on two-dimensional linkage geometries, bilaterally symmetrical pairs of planar linkages, or single four-bar linkages. Here, we present new, three-dimensional (3D), parallel linkage models of the skulls of birds and fishes and use these models (available as free kinematic simulation software), to investigate structure-function relationships in these systems. This new computational framework provides an accessible and integrated workflow for exploring the evolution of structure and function in complex musculoskeletal systems. Linkage simulations show that kinematic transmission, although a suitable functional metric for linkages with single rotating input and output links, can give misleading results when applied to linkages with substantial translational components or multiple output links. To take into account both linear and rotational displacement we define force mechanical advantage for a linkage (analogous to lever mechanical advantage) and apply this metric to measure transmission efficiency in the bird cranial mechanism. For linkages with multiple, expanding output points we propose a new functional metric, expansion advantage, to measure expansion amplification and apply this metric to the buccal expansion mechanism in fishes. Using the bird cranial linkage model, we quantify the inaccuracies that result from simplifying a 3D geometry into two dimensions. We also show that by combining single-chain linkages into parallel linkages, more links can be simulated while decreasing or maintaining the same number of input parameters. This generalized framework for linkage simulation and analysis can accommodate linkages of differing

  17. STAKEHOLDER LINKAGES FOR SUSTAINABLE LAND ...

    African Journals Online (AJOL)

    Osondu

    Key words: Stakeholders; farmer-expert linkages; resource management; Ethiopia. Introduction ... decentralized democratic decision making processes and thus ..... district offices within the given time limits. They were often .... -less willing and less ready to hearing weaker performance reports (expect more success with ...

  18. Endocrine changes associated with spawning behavior and social stimuli in a wild population of rainbow trout (Salmo gairdneri). II. Females

    OpenAIRE

    Liley, N.R.; Fostier, Alexis; Breton, B.; Tan, E.S.P.

    1986-01-01

    Rainbow trout (Salmo gairdneri) were collected from a natural spawning population at Pennask Lake, B.C. Blood samples taken from female trout at different stages of spawning were assayed by radioimmunoassay for gonadotropin (GtH), estradiol-17 beta (E2), androgens, including testosterone (T), and 17α-hydroxy-20 β-dihydroprogesterone (17,20-P). Plasma levels of androgen and estradiol were highest in females sampled shortly before ovulation (ogreeno females) and declined in ovulated and sexuall...

  19. ANALISIS KEBIJAKAN LINKAGE PROGRAM LEMBAGA KEUANGAN SYARIAH DALAM RANGKA PEMBERDAYAAN UKM DI INDONESIA

    Directory of Open Access Journals (Sweden)

    Siti Hamidah

    2016-03-01

    Linkage program adalah program yang menghubungkan bank dengan pelaku usaha mikro kecil melalui lembaga keuangan mikro. Kelemahan dalam Linkage program adalah pada aspek peraturan yang tersebar dalam berbagai aturan, dan khusus bagi lembaga keuangan syariah terdapat pula kendala berkaitan dengan kesesuaian dengan ketentuan syariah. Dari penelitian dengan pendekatan perundang-undangan dan pendekatan konseptual ini diperoleh inventarisasi serta analisis kebijakan Linkage Program bagi Lembaga Keuangan Syariah dalam hukum positif Indonesia. Kebijakan terkait Linkage program, diklasifikasi dalam 2 kelompok, yaitu kebijakan substansi dan prosedural. Aturan inilah yang menjadi rujukan bagi lembaga keuangan syariah rangka pemberdayaan usaha kecil mikro di Indonesia. Kata kunci: Linkage program, lembaga keuangan syariah, usaha mikro kecil

  20. Electrostatic microactuators with integrated gear linkages for mechanical power transmission

    NARCIS (Netherlands)

    Legtenberg, R.; Legtenberg, Rob; Berenschot, Johan W.; Elwenspoek, Michael Curt; Fluitman, J.H.J.

    1996-01-01

    In this paper a surface micromachining process is presented which has been used to fabricate electrostatic microactuators that are interconnected with each other and linked to other movable microstructures by integrated gear linkages. The gear linkages consist of rotational and linear gear

  1. Influence of small hydropower plants on brown trout (Salmo trutta L. population in Mislinja River

    Directory of Open Access Journals (Sweden)

    Blaž Cokan

    2013-12-01

    Full Text Available The brown trout (Salmo trutta L. in the Mislinja River has been endangered for years because of small hydroelectric power plants. To find out how they are affecting the population of the brown trout in the Mislinja River, we conducted a sampling of the brown trout, using a generating set. We measured the length and weight of all caught specimens and analysed the obtained data. The results are presented in this paper, e.g., biomass, estimations of abundance, average weight, average length and number of captured brown trout. We discovered that the population of the brown trout has decreased in all the sections where water has been taken away for small hydroelectric power plants.

  2. Assessment of digestive enzymes activity during the fry development of the endangered Caspian brown trout Salmo caspius.

    Science.gov (United States)

    Zamani, A; Hajimoradloo, A; Madani, R; Farhangi, M

    2009-09-01

    The study of digestive enzymes activity at Salmo caspius fry showed that enzymes were available at the moment of mouth opening on the first day post hatching (dph) and the activity of enzymes showed no significant difference from the hatching day 28 dph. An increased activity was seen between 32 and 43 dph and this activity was significantly higher than the activity during the first 28 days. In the primary stages after yolk sac resorption (43-58 dph), enzymes activity showed an increased profile, however none of them showed a significant difference between 43 and 58 dph.

  3. The Effects of Run-of-River Hydroelectric Power Schemes on Fish Community Composition in Temperate Streams and Rivers.

    Science.gov (United States)

    Bilotta, Gary S; Burnside, Niall G; Gray, Jeremy C; Orr, Harriet G

    2016-01-01

    The potential environmental impacts of large-scale storage hydroelectric power (HEP) schemes have been well-documented in the literature. In Europe, awareness of these potential impacts and limited opportunities for politically-acceptable medium- to large-scale schemes, have caused attention to focus on smaller-scale HEP schemes, particularly run-of-river (ROR) schemes, to contribute to meeting renewable energy targets. Run-of-river HEP schemes are often presumed to be less environmentally damaging than large-scale storage HEP schemes. However, there is currently a lack of peer-reviewed studies on their physical and ecological impact. The aim of this article was to investigate the effects of ROR HEP schemes on communities of fish in temperate streams and rivers, using a Before-After, Control-Impact (BACI) study design. The study makes use of routine environmental surveillance data collected as part of long-term national and international monitoring programmes at 23 systematically-selected ROR HEP schemes and 23 systematically-selected paired control sites. Six area-normalised metrics of fish community composition were analysed using a linear mixed effects model (number of species, number of fish, number of Atlantic salmon-Salmo salar, number of >1 year old Atlantic salmon, number of brown trout-Salmo trutta, and number of >1 year old brown trout). The analyses showed that there was a statistically significant effect (pcomposition. The implications of these findings are discussed in this article and recommendations are made for best-practice study design for future fish community impact studies.

  4. Genomewide Linkage Screen for Waldenström Macroglobulinemia Susceptibility Loci in High-Risk Families

    Science.gov (United States)

    McMaster, Mary L.; Goldin, Lynn R.; Bai, Yan; Ter-Minassian, Monica; Boehringer, Stefan; Giambarresi, Therese R.; Vasquez, Linda G.; Tucker, Margaret A.

    2006-01-01

    Waldenström macroglobulinemia (WM), a distinctive subtype of non-Hodgkin lymphoma that features overproduction of immunoglobulin M (IgM), clearly has a familial component; however, no susceptibility genes have yet been identified. We performed a genomewide linkage analysis in 11 high-risk families with WM that were informative for linkage, for a total of 122 individuals with DNA samples, including 34 patients with WM and 10 patients with IgM monoclonal gammopathy of undetermined significance (IgM MGUS). We genotyped 1,058 microsatellite markers (average spacing 3.5 cM), performed both nonparametric and parametric linkage analysis, and computed both two-point and multipoint linkage statistics. The strongest evidence of linkage was found on chromosomes 1q and 4q when patients with WM and with IgM MGUS were both considered affected; nonparametric linkage scores were 2.5 (P=.0089) and 3.1 (P=.004), respectively. Other locations suggestive of linkage were found on chromosomes 3 and 6. Results of two-locus linkage analysis were consistent with independent effects. The findings from this first linkage analysis of families at high risk for WM represent important progress toward identifying gene(s) that modulate susceptibility to WM and toward understanding its complex etiology. PMID:16960805

  5. Heritability and whole genome linkage of pulse pressure in Chinese twin pairs

    DEFF Research Database (Denmark)

    Jiang, Wengjie; Zhang, Dongfeng; Pang, Zengchang

    2012-01-01

    with a heritability estimate of 0.45. Genome-wide non-parametric linkage analysis identified three significant linkage peaks on chromosome 11 (lod score 4.06 at 30.5 cM), chromosome 12 (lod score 3.97 at 100.7 cM), and chromosome 18 (lod score 4.01 at 70.7 cM) with the last two peaks closely overlapping with linkage...

  6. EDITORIAL Development Linkages between Tree Breeding ...

    African Journals Online (AJOL)

    EDITORIAL Development Linkages between Tree Breeding Programmes and National/Regional Tree Seed Centres in Africa. ... Discovery and Innovation. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives.

  7. Entrepreneurship And Business Management - Exploring Linkages For Sustainable Development

    Directory of Open Access Journals (Sweden)

    Dr Serah K Mbetwa

    2015-08-01

    Full Text Available Entrepreneurs have emerged as market leaders in todays business world amidst the numerous economic turmoil constantly affecting economies on a global scale. This research paper is on entrepreneurship and business management and its linkages to other business stakeholders. The research paper therefore discusses entrepreneurship and business management exploring the linkages to available financing and potential institutions for startup capital by linking entrepreneurs to the government financiers and the public clientele. It is believed that this can bring about achievement of sustainable development goals translating into sustainable development and hence economic growth. The idea of funding is echoed by Robert Rice 2016 An entrepreneur without funding is like a musician with no instruments. Sustainability and entrepreneurship sustainopreneurship is made possible with availability of information on linkages between entrepreneurs and financial lending institutions as well as government policy. It is hoped that the research will add to the existing knowledge and help entrepreneurs with funding options for their business ideas to come to life. Findings show that the government financial lending institutions and the public are the major linkages between entrepreneurship and business management and are critical for attaining sustainable development goals and achieving economic growth.

  8. Nance-Horan syndrome: linkage analysis in a family from The Netherlands.

    Science.gov (United States)

    Bergen, A A; ten Brink, J; Schuurman, E J; Bleeker-Wagemakers, E M

    1994-05-01

    Linkage analysis was carried out in a Dutch family with Nance-Horan (NH) syndrome. Close linkage without recombination between NH and the Xp loci DXS207, DXS43, and DXS365 (zmax = 3.23) was observed. Multipoint linkage analysis and the analysis of recombinations in multiple informative meioses suggest the genetic order Xcen-DMD (exon 49)-DXS451-(NH, DXS207, DXS365, DXS43)-(STS, DXF30)-Xpter. These data refine the localization of the NH locus on the distal Xp.

  9. A genetic linkage map of hexaploid naked oat constructed with SSR markers

    Directory of Open Access Journals (Sweden)

    Gaoyuan Song

    2015-08-01

    Full Text Available Naked oat is a unique health food crop in China. Using 202 F2 individuals derived from a hybrid between the variety 578 and the landrace Sanfensan, we constructed a genetic linkage map consisting of 22 linkage groups covering 2070.50 cM and including 208 simple sequence repeat (SSR markers. The minimum distance between adjacent markers was 0.01 cM and the average was 9.95 cM. Each linkage group contained 2–22 markers. The largest linkage group covered 174.40 cM and the shortest one covered 36.80 cM, with an average of 94.11 cM. Thirty-six markers (17.3% showing distorted segregation were distributed across linkage groups LG5 to LG22. This map complements published oat genetic maps and is applicable for quantitative trait locus analysis, gene cloning and molecular marker-assisted selection.

  10. Meta-analysis of 32 genome-wide linkage studies of schizophrenia

    Science.gov (United States)

    Ng, MYM; Levinson, DF; Faraone, SV; Suarez, BK; DeLisi, LE; Arinami, T; Riley, B; Paunio, T; Pulver, AE; Irmansyah; Holmans, PA; Escamilla, M; Wildenauer, DB; Williams, NM; Laurent, C; Mowry, BJ; Brzustowicz, LM; Maziade, M; Sklar, P; Garver, DL; Abecasis, GR; Lerer, B; Fallin, MD; Gurling, HMD; Gejman, PV; Lindholm, E; Moises, HW; Byerley, W; Wijsman, EM; Forabosco, P; Tsuang, MT; Hwu, H-G; Okazaki, Y; Kendler, KS; Wormley, B; Fanous, A; Walsh, D; O’Neill, FA; Peltonen, L; Nestadt, G; Lasseter, VK; Liang, KY; Papadimitriou, GM; Dikeos, DG; Schwab, SG; Owen, MJ; O’Donovan, MC; Norton, N; Hare, E; Raventos, H; Nicolini, H; Albus, M; Maier, W; Nimgaonkar, VL; Terenius, L; Mallet, J; Jay, M; Godard, S; Nertney, D; Alexander, M; Crowe, RR; Silverman, JM; Bassett, AS; Roy, M-A; Mérette, C; Pato, CN; Pato, MT; Roos, J Louw; Kohn, Y; Amann-Zalcenstein, D; Kalsi, G; McQuillin, A; Curtis, D; Brynjolfson, J; Sigmundsson, T; Petursson, H; Sanders, AR; Duan, J; Jazin, E; Myles-Worsley, M; Karayiorgou, M; Lewis, CM

    2009-01-01

    A genome scan meta-analysis (GSMA) was carried out on 32 independent genome-wide linkage scan analyses that included 3255 pedigrees with 7413 genotyped cases affected with schizophrenia (SCZ) or related disorders. The primary GSMA divided the autosomes into 120 bins, rank-ordered the bins within each study according to the most positive linkage result in each bin, summed these ranks (weighted for study size) for each bin across studies and determined the empirical probability of a given summed rank (PSR) by simulation. Suggestive evidence for linkage was observed in two single bins, on chromosomes 5q (142-168 Mb) and 2q (103-134 Mb). Genome-wide evidence for linkage was detected on chromosome 2q (119-152 Mb) when bin boundaries were shifted to the middle of the previous bins. The primary analysis met empirical criteria for ‘aggregate’ genome-wide significance, indicating that some or all of 10 bins are likely to contain loci linked to SCZ, including regions of chromosomes 1, 2q, 3q, 4q, 5q, 8p and 10q. In a secondary analysis of 22 studies of European-ancestry samples, suggestive evidence for linkage was observed on chromosome 8p (16-33 Mb). Although the newer genome-wide association methodology has greater power to detect weak associations to single common DNA sequence variants, linkage analysis can detect diverse genetic effects that segregate in families, including multiple rare variants within one locus or several weakly associated loci in the same region. Therefore, the regions supported by this meta-analysis deserve close attention in future studies. PMID:19349958

  11. Robust LOD scores for variance component-based linkage analysis.

    Science.gov (United States)

    Blangero, J; Williams, J T; Almasy, L

    2000-01-01

    The variance component method is now widely used for linkage analysis of quantitative traits. Although this approach offers many advantages, the importance of the underlying assumption of multivariate normality of the trait distribution within pedigrees has not been studied extensively. Simulation studies have shown that traits with leptokurtic distributions yield linkage test statistics that exhibit excessive Type I error when analyzed naively. We derive analytical formulae relating the deviation from the expected asymptotic distribution of the lod score to the kurtosis and total heritability of the quantitative trait. A simple correction constant yields a robust lod score for any deviation from normality and for any pedigree structure, and effectively eliminates the problem of inflated Type I error due to misspecification of the underlying probability model in variance component-based linkage analysis.

  12. Daytime habitat selection for juvenile parr brown trout (Salmo trutta) in small lowland streams

    DEFF Research Database (Denmark)

    Conallin, J.; Boegh, E.; Olsen, M.

    2014-01-01

    Physical habitat is important in determining the carrying capacity of juvenile brown trout, and within freshwater management. Summer daytime physical habitat selection for the parr lifestage (7-20 cm) juvenile brown trout (Salmo trutta) was assessed in 6 small lowland streams. Habitat preference...... was determined for the four variables; water velocity, water depth, substrate and cover, and the preferences for physical habitat selection were expressed in terms of habitat suitability indices (HSI's). The statistical confidence of HSI's was evaluated using power analysis. It was found that a minimum of 22...... fish observations was needed to have statistical confidence in the HSIs for water depth, and a minimum of 92 fish observations for water velocity during daytime summer conditions. Generally parr were utilising the deeper habitats, indicating preference for deeper water. Cover was also being selected...

  13. Linkage of biomolecules to solid phases for immunoassay

    International Nuclear Information System (INIS)

    Chapman, R.S.

    1998-01-01

    Topics covered by this lecture include a brief review of the principal methods of linkage of biomolecules to solid phase matrices. Copies of the key self explanatory slides are presented as figures together with reprints of two publications by the author dealing with a preferred chemistry for the covalent linkage of antibodies to hydroxyl and amino functional groups and the effects of changes in solid phase matrix and antibody coupling chemistry on the performance of a typical excess reagent immunoassay for thyroid stimulating hormone

  14. Preliminary genetic linkage map of the abalone Haliotis diversicolor Reeve

    Science.gov (United States)

    Shi, Yaohua; Guo, Ximing; Gu, Zhifeng; Wang, Aimin; Wang, Yan

    2010-05-01

    Haliotis diversicolor Reeve is one of the most important mollusks cultured in South China. Preliminary genetic linkage maps were constructed with amplified fragment length polymorphism (AFLP) markers. A total of 2 596 AFLP markers were obtained from 28 primer combinations in two parents and 78 offsprings. Among them, 412 markers (15.9%) were polymorphic and segregated in the mapping family. Chi-square tests showed that 151 (84.4%) markers segregated according to the expected 1:1 Mendelian ratio ( P<0.05) in the female parent, and 200 (85.8%) in the male parent. For the female map, 179 markers were used for linkage analysis and 90 markers were assigned to 17 linkage groups with an average interval length of 25.7 cm. For the male map, 233 markers were used and 94 were mapped into 18 linkage groups, with an average interval of 25.0 cm. The estimated genome length was 2 773.0 cm for the female and 2 817.1 cm for the male map. The observed length of the linkage map was 1 875.2 cm and 1 896.5 cm for the female and male maps, respectively. When doublets were considered, the map length increased to 2 152.8 cm for the female and 2 032.7 cm for the male map, corresponding to genome coverage of 77.6% and 72.2%, respectively.

  15. Three brown trout Salmo trutta lineages in Corsica described through allozyme variation.

    Science.gov (United States)

    Berrebi, P

    2015-01-01

    The brown trout Salmo trutta is represented by three lineages in Corsica: (1) an ancestral Corsican lineage, (2) a Mediterranean lineage and (3) a recently stocked domestic Atlantic S. trutta lineage (all are interfertile); the main focus of this study was the ancestral Corsican S. trutta, but the other lineages were also considered. A total of 38 samples captured between 1993 and 1998 were analysed, with nearly 1000 individuals considered overall. The Corsican ancestral lineage (Adriatic lineage according to the mitochondrial DNA control region nomenclature, AD) mostly inhabits streams in the southern half of the island; the Mediterranean lineage (ME) is present more in the north, especially in Golu River, but most populations are an admixture of these lineages and the domestic Atlantic S. trutta (AT). Locations where the Corsican ancestral S. trutta is dominant are now protected against stocking and sometimes fishing is also forbidden. The presence of the Corsican S. trutta is unique in France. © 2014 The Fisheries Society of the British Isles.

  16. Genetic variation in steelhead (Salmo gairdneri) from the north coast of Washington

    Science.gov (United States)

    Reisenbichler, R.R.; Phelps, S.R.

    1989-01-01

    Steelhead (Salmo gairdneri) collected from various sites in nine drainages in northwestern Washington were genetically characterized at 65 protein-coding loci by starch-gel electrophoresis. Genetic differentiation within and among drainages was not significant, and genetic variation among drainages was much less than that reported in British Columbia; these results may be the consequence of gene flow from hatchery stocks that have been released in Washington since the 1940's. Allele frequencies varied significantly among year-classes (hence, genetic characterization studies must include data from several year-classes), and also between hatchery fish (including a stock developed with local wild fish) and wild fish, indicating that few wild fish have been successfully and routinely included in hatchery brood stocks. Conservation of genetic diversity along the north coast of Washington should be facilitated by reducing the numbers of hatchery fish that spawn in streams and by including wild fish in hatchery brood stocks.

  17. Survival and progression rates of anadromous brown trout kelts Salmo trutta during downstream migration in freshwater and at sea

    DEFF Research Database (Denmark)

    Aarestrup, Kim; Baktoft, Henrik; Thorstad, EB

    2015-01-01

    The marine migration of post-spawning anadromous fish remains poorly understood. The present study examined survival and progression rates of anadromous brown trout Salmo trutta L. after spawning (kelts) during downriver, fjord, and sea migration. Kelts (n = 49) were captured in the Danish River...... completing the reach within 4 d, suggesting that the kelts spent limited time foraging after returning to the fjord. The total survival during the entire marine migration, including the fjord, was a minimum of 29%. Our study provides data that are important for management of anadromous brown trout...

  18. Selenium and selenium species in feeds and muscle tissue of Atlantic salmon

    DEFF Research Database (Denmark)

    Sele, Veronika; Ørnsrud, Robin; Sloth, Jens Jørgen

    2018-01-01

    Selenium (Se) is an essential element for animals, including fish. Due to changes in feed composition for Atlantic salmon (Salmo salar), it may be necessary to supplement feeds with Se. In the present work, the transfer of Se and Se species from feed to muscle of Atlantic salmon fed Se supplemented...... diets was studied. Salmon were fed basal fish feed (0.35 mg Se/kg and 0.89 mg Se/kg feed), or feed supplemented either with selenised yeast or sodium selenite, at low (1–2 mg Se/kg feed) and high (15 mg Se/kg feed) levels, for 12 weeks. For the extraction of Se species from fish muscle, enzymatic...... cleavage with protease type XIV was applied. The extraction methods for Se species from fish feed were optimised, and two separate extraction procedures were applied, 1) enzymatic cleavage for organic Se supplemented feeds and 2) weak alkaline solvent for inorganic Se supplemented feeds, respectively...

  19. Free polyunsaturated fatty acids cause taste deterioration of salmon during frozen storage

    DEFF Research Database (Denmark)

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

    2000-01-01

    Increased intensity of train oil taste, bitterness, and metal taste are the most pronounced sensory changes during frozen storage of salmon (Refsgaard, H. H. F.; Brockhoff, P. B.; Jensen, B. Sensory and Chemical Changes in Farmed Atlantic Salmon (Salmo salar) during Frozen Storage. J. Agric. Food...... Chem. 1998a, 46, 3473-3479). Addition of each of the unsaturated fatty acids: palmitoleic acid (16:1, n - 7), linoleic acid (C18:2, it - 6), eicosapentaenoic acid (EPA; C20:5, it - 3) and docosahexaenoic acid (DHA; C22:6, n. - 3) to fresh minced salmon changed the sensory perception and increased...... the intensity of train oil taste, bitterness, and metal taste. The added level of each fatty acid (similar to 1 mg/g salmon meat) was equivalent to the concentration of the fatty acids determined in salmon stored as fillet at -10 degrees C for 6 months. The effect of addition of the fatty acids on the intensity...

  20. A multiple-locus variable-number tandem repeat analysis (MLVA) of Listeria monocytogenes isolated from Norwegian salmon-processing factories and from listeriosis patients.

    Science.gov (United States)

    Lunestad, B T; Truong, T T T; Lindstedt, B-A

    2013-10-01

    The objective of this study was to characterize Listeria monocytogenes isolated from farmed Atlantic salmon (Salmo salar) and the processing environment in three different Norwegian factories, and compare these to clinical isolates by multiple-locus variable-number tandem repeat analysis (MLVA). The 65 L. monocytogenes isolates obtained gave 15 distinct MLVA profiles. There was great heterogeneity in the distribution of MLVA profiles in factories and within each factory. Nine of the 15 MLVA profiles found in the fish-associated isolates were found to match human profiles. The MLVA profile 07-07-09-10-06 was the most common strain in Norwegian listeriosis patients. L. monocytogenes with this profile has previously been associated with at least two known listeriosis outbreaks in Norway, neither determined to be due to fish consumption. However, since this profile was also found in fish and in the processing environment, fish should be considered as a possible food vehicle during sporadic cases and outbreaks of listeriosis.

  1. An evaluation of the duration of efficacy of emamectin benzoate in the control of Caligus curtus Müller infestations in Atlantic cod, Gadus morhua L.

    Science.gov (United States)

    Hamre, L A; Lunestad, B T; Hannisdal, R; Samuelsen, O B

    2011-06-01

    The duration of efficacy of emamectin benzoate in the control of Caligus curtus infestations in Atlantic cod, Gadus morhua L., was studied following an administration of 50 μg kg⁻¹ for seven consecutive days. No lice were found on medicated fish when challenged 1 week (challenge 1) or 5 weeks (challenge 2) following termination of medication, whereas the mean abundance of lice among the unmedicated fish was 17.9 and 19.3 lice per fish in challenge 1 and 2, respectively. Muscle concentrations of 19.5 ± 8.2 ng g⁻¹ and 3.4 ± 0.9 ng g⁻¹, respectively, and skin concentrations of 23.1 ± 10.8 and 4.2 ± 1.0 ng g⁻¹, respectively, were found 27 and 55 days following the termination of medication. Tissue concentrations and the duration of efficacy indicate a dosing regime for emamectin in cod, similar to the regime used for Atlantic salmon, Salmo salar L. © 2011 Blackwell Publishing Ltd.

  2. CO2 Plant Extracts Reduce Cholesterol Oxidation in Fish Patties during Cooking and Storage.

    Science.gov (United States)

    Tarvainen, Marko; Quirin, Karl-Werner; Kallio, Heikki; Yang, Baoru

    2016-12-28

    Cholesterol oxidation products (COPs) in foods may pose risks for human health. Suitable antioxidants can reduce the formation of COPs in industrial products. Consumer awareness of food additives has brought a need for more natural alternatives. This is the first study on the effects of supercritical CO 2 extracts of rosemary, oregano, and an antimicrobial blend of seven herbs, tested at two levels (1 and 3 g/kg fish), against cholesterol oxidation in patties made of a widely consumed fish species, Atlantic salmon (Salmo salar), during baking and storage. Cholesterol oxidation was reduced by the extracts as indicated by lowered levels of 7α-hydroxycholesterol, 7β-hydroxycholesterol, and 7-ketocholesterol, which were quantified by GC-MS. The total amount of COPs was smaller in all of the cooked samples containing the plant extracts (<1 μg/g extracted fat) than in the cooked control (14 μg/g). Furthermore, the plant extracts exhibited protective effects also during cold storage for up to 14 days.

  3. Differentiation of fresh and frozen-thawed fish samples using Raman spectroscopy coupled with chemometric analysis.

    Science.gov (United States)

    Velioğlu, Hasan Murat; Temiz, Havva Tümay; Boyaci, Ismail Hakki

    2015-04-01

    The potential of Raman spectroscopy was investigated in terms of its capability to discriminate the species of the fish samples and determine their freshness according to the number of freezing/thawing cycles they exposed. Species discrimination analysis was carried out on sixty-four fish samples from six different species, namely horse mackerel (Trachurus trachurus), European anchovy (Engraulis encrasicolus), red mullet (Mullus surmuletus), Bluefish (Pomatamus saltatrix), Atlantic salmon (Salmo salar) and flying gurnard (Trigla lucerna). Afterwards, fish samples were exposed to different numbers of freezing/thawing cycles and separated into three batches, namely (i) fresh, (ii) once frozen-thawed (OF) and (iii) twice frozen-thawed (TF) samples, in order to perform the freshness analysis. Raman data collected were used as inputs for chemometric analysis, which enabled us to develop two main PCA models to successfully terminate the studies for both species discrimination and freshness determination analysis. Copyright © 2014 Elsevier Ltd. All rights reserved.

  4. Examination of the influence of juvenile Atlantic salmon on the feeding mode of juvenile steelhead in Lake Ontario tributaries

    Science.gov (United States)

    Johnson, James H.; Waldt, Emily M.

    2014-01-01

    We examined diets of 1204 allopatric and sympatric juvenile Atlantic salmon (Salmo salar) and steelhead (Oncorhynchus mykiss) in three tributaries of Lake Ontario. The diet composition of both species consisted primarily of ephemeropterans, trichopterans, and chironomids, although juvenile steelhead consumed more terrestrial invertebrates, especially at the sympatric sites. Subyearlings of both species consumed small prey (i.e. chironomids) whereas large prey (i.e. perlids) made up a higher percentage of the diet of yearlings. The diet of juvenile steelhead at the allopatric sites was more closely associated with the composition of the benthos than with the drift, but was about equally associated with the benthos and drift at the sympatric sites. The diet of both subyearling and yearling Atlantic salmon was more closely associated with the benthos than the drift at the sympatric sites. The evidence suggests that juvenile steelhead may subtly alter their feeding behavior in sympatry with Atlantic salmon. This behavioral adaptation may reduce competitive interactions between these species.

  5. A Simple Sampling Method for Estimating the Accuracy of Large Scale Record Linkage Projects.

    Science.gov (United States)

    Boyd, James H; Guiver, Tenniel; Randall, Sean M; Ferrante, Anna M; Semmens, James B; Anderson, Phil; Dickinson, Teresa

    2016-05-17

    Record linkage techniques allow different data collections to be brought together to provide a wider picture of the health status of individuals. Ensuring high linkage quality is important to guarantee the quality and integrity of research. Current methods for measuring linkage quality typically focus on precision (the proportion of incorrect links), given the difficulty of measuring the proportion of false negatives. The aim of this work is to introduce and evaluate a sampling based method to estimate both precision and recall following record linkage. In the sampling based method, record-pairs from each threshold (including those below the identified cut-off for acceptance) are sampled and clerically reviewed. These results are then applied to the entire set of record-pairs, providing estimates of false positives and false negatives. This method was evaluated on a synthetically generated dataset, where the true match status (which records belonged to the same person) was known. The sampled estimates of linkage quality were relatively close to actual linkage quality metrics calculated for the whole synthetic dataset. The precision and recall measures for seven reviewers were very consistent with little variation in the clerical assessment results (overall agreement using the Fleiss Kappa statistics was 0.601). This method presents as a possible means of accurately estimating matching quality and refining linkages in population level linkage studies. The sampling approach is especially important for large project linkages where the number of record pairs produced may be very large often running into millions.

  6. Hereditary spastic paraplegia: LOD-score considerations for confirmation of linkage in a heterogeneous trait

    Energy Technology Data Exchange (ETDEWEB)

    Dube, M.P.; Kibar, Z.; Rouleau, G.A. [McGill Univ., Quebec (Canada)] [and others

    1997-03-01

    Hereditary spastic paraplegia (HSP) is a degenerative disorder of the motor system, defined by progressive weakness and spasticity of the lower limbs. HSP may be inherited as an autosomal dominant (AD), autosomal recessive, or an X-linked trait. AD HSP is genetically heterogeneous, and three loci have been identified so far: SPG3 maps to chromosome 14q, SPG4 to 2p, and SPG4a to 15q. We have undertaken linkage analysis with 21 uncomplicated AD families to the three AD HSP loci. We report significant linkage for three of our families to the SPG4 locus and exclude several families by multipoint linkage. We used linkage information from several different research teams to evaluate the statistical probability of linkage to the SPG4 locus for uncomplicated AD HSP families and established the critical LOD-score value necessary for confirmation of linkage to the SPG4 locus from Bayesian statistics. In addition, we calculated the empirical P-values for the LOD scores obtained with all families with computer simulation methods. Power to detect significant linkage, as well as type I error probabilities, were evaluated. This combined analytical approach permitted conclusive linkage analyses on small to medium-size families, under the restrictions of genetic heterogeneity. 19 refs., 1 fig., 1 tab.

  7. Hereditary spastic paraplegia: LOD-score considerations for confirmation of linkage in a heterogeneous trait.

    Science.gov (United States)

    Dubé, M P; Mlodzienski, M A; Kibar, Z; Farlow, M R; Ebers, G; Harper, P; Kolodny, E H; Rouleau, G A; Figlewicz, D A

    1997-03-01

    Hereditary spastic paraplegia (HSP) is a degenerative disorder of the motor system, defined by progressive weakness and spasticity of the lower limbs. HSP may be inherited as an autosomal dominant (AD), autosomal recessive, or an X-linked trait. AD HSP is genetically heterogeneous, and three loci have been identified so far: SPG3 maps to chromosome 14q, SPG4 to 2p, and SPG4a to 15q. We have undertaken linkage analysis with 21 uncomplicated AD families to the three AD HSP loci. We report significant linkage for three of our families to the SPG4 locus and exclude several families by multipoint linkage. We used linkage information from several different research teams to evaluate the statistical probability of linkage to the SPG4 locus for uncomplicated AD HSP families and established the critical LOD-score value necessary for confirmation of linkage to the SPG4 locus from Bayesian statistics. In addition, we calculated the empirical P-values for the LOD scores obtained with all families with computer simulation methods. Power to detect significant linkage, as well as type I error probabilities, were evaluated. This combined analytical approach permitted conclusive linkage analyses on small to medium-size families, under the restrictions of genetic heterogeneity.

  8. Survival of radio-tagged Atlantic salmon ( Salmo salar L.) and trout ( Salmo trutta L.) smolts passing a reservoir during seaward migration

    DEFF Research Database (Denmark)

    Jepsen, Niels; Aarestrup, Kim; Økland, F.

    1998-01-01

    tagged with internal miniature radio-transmitters, and released in the river just upstream the reservoir on May 1, 1996. The salmon smelts were hatchery-reared, while the trout smelts were wild fish, caught in a smelt trap. The tagged smelts were tracked daily for 3 weeks, and when possible the cause...

  9. Occurrence and variation of egg cannibalism in brown trout Salmo trutta

    Science.gov (United States)

    Aymes, Jean-Christophe; Larrieu, Maider; Tentelier, Cédric; Labonne, Jacques

    2010-04-01

    Egg cannibalism is a common behavior among fish taxa and is largely studied in species with parental care. Heterocannibalism and filial cannibalism have both been reported in salmonids, a group with no extended parental care, but the topic remained somewhat under-documented, especially in brown trout ( Salmo trutta). In the present study, 83 spawning events were recorded finely with high-resolution video in three natural populations. Redd covering dynamics by females and the timing of cannibalism showed that eggs were vulnerable mainly during the first 120 s after spawning. Cannibalism occurred in 25% of spawnings and was principally perpetrated by peripherals but the sires also cannibalized their brood, especially after multiple mating. The probability of cannibalism increased with operational sex ratio but did not correlate with the date in spawning season. Occurrence of cannibalism also differed between populations. Our results suggest that such behavior is frequent and may reduce the fitness of parents. Its evolutionary implications for population ecology should be considered, since it appeared to be controlled by environmental and spatial factors.

  10. Evidence for an asthma risk locus on chromosome Xp: a replication linkage study

    DEFF Research Database (Denmark)

    Brasch-Andersen, C; Møller, M U; Haagerup, A

    2008-01-01

    replication sample as used in the present study. The aim of the study was to replicate linkage to candidate regions for asthma in an independent Danish sample. METHODS: We performed a replication study investigating linkage to candidate regions for asthma on chromosomes 1p36.31-p36.21, 5q15-q23.2, 6p24.3-p22...... studies have been carried out the results are still conflicting and call for replication experiments. A Danish genome-wide scan has prior reported evidence for candidate regions for asthma susceptibility genes on chromosomes 1p, 5q, 6p, 12q and Xp. Linkage to chromosome 12q was later confirmed in the same.......3, and Xp22.31-p11.4 using additional markers in an independent set of 136 Danish asthmatic sib pair families. RESULTS: Nonparametric multipoint linkage analyses yielded suggestive evidence for linkage to asthma to chromosome Xp21.2 (MLS 2.92) but failed to replicate linkage to chromosomes 1p36.31-p36.21, 5...

  11. The acceptability of conducting data linkage research without obtaining consent: lay people's views and justifications.

    Science.gov (United States)

    Xafis, Vicki

    2015-11-17

    A key ethical issue arising in data linkage research relates to consent requirements. Patients' consent preferences in the context of health research have been explored but their consent preferences regarding data linkage specifically have been under-explored. In addition, the views on data linkage are often those of patient groups. As a result, little is known about lay people's views and their preferences about consent requirements in the context of data linkage. This study explores lay people's views and justifications regarding the acceptability of conducting data linkage research without obtaining consent. A qualitative study explored lay people's views regarding consent requirements in data linkage via four hypothetical data linkage scenarios of increasing complexity. Prior to considering the scenarios, participants were provided with information regarding best practice data linkage processes via discussion and a diagrammatic representation of the process. Lay people were able to understand the intricate processes involved in data linkage and the key protections afforded within a short amount of time. They were supportive of data linkage research and, on the whole, believed it should be conducted without consent provided a data linkage organization de-identifies the data used so that researchers do not handle identifiable data. Many thought that de-identified data holds a different status to identifiable data and should be used without specific consent in research that aims to benefit society. In weighing up conflicting values and interests, participants shifted consent preferences before arriving at their final consent preference for each scenario and provided justifications for their choices. They considered the protection of people's information, societal benefits, and the nature and constraints of research and recognized that these need to be balanced. With some exposure to the features of data linkage, lay people have the capacity to understand the

  12. Model reduction of detailed-balanced reaction networks by clustering linkage classes

    NARCIS (Netherlands)

    Rao, Shodhan; Jayawardhana, Bayu; van der Schaft, Abraham; Findeisen, Rolf; Bullinger, Eric; Balsa-Canto, Eva; Bernaerts, Kristel

    2016-01-01

    We propose a model reduction method that involves sequential application of clustering of linkage classes and Kron reduction. This approach is specifically useful for chemical reaction networks with each linkage class having less number of reactions. In case of detailed balanced chemical reaction

  13. Balancing of linkages and robot manipulators advanced methods with illustrative examples

    CERN Document Server

    Arakelian, Vigen

    2015-01-01

    In this book advanced balancing methods for planar and spatial linkages, hand operated and automatic robot manipulators are presented. It is organized into three main parts and eight chapters. The main parts are the introduction to balancing, the balancing of linkages and the balancing of robot manipulators. The review of state-of-the-art literature including more than 500 references discloses particularities of shaking force/moment balancing and gravity compensation methods. Then new methods for balancing of linkages are considered. Methods provided in the second part of the book deal with the partial and complete shaking force/moment balancing of various linkages. A new field for balancing methods applications is the design of mechanical systems for fast manipulation. Special attention is given to the shaking force/moment balancing of robot manipulators. Gravity balancing methods are also discussed. The suggested balancing methods are illustrated by numerous examples.

  14. A literature review of record linkage procedures focusing on infant health outcomes

    Directory of Open Access Journals (Sweden)

    Carla Jorge Machado

    Full Text Available Record linkage is a powerful tool in assembling information from different data sources and has been used by a number of public health researchers. In this review, we provide an overview of the record linkage methodologies, focusing particularly on probabilistic record linkage. We then stress the purposes and research applications of linking records by focusing on studies of infant health outcomes based on large data sets, and provide a critical review of the studies in Brazil.

  15. Sustaining innovations : schools, institutions and linkages in the Cuzco region, Peru

    NARCIS (Netherlands)

    ChavezTafur, J.

    1998-01-01

    This thesis is about linkages between the different institutions operating in the rural areas and the contributions these linkages provide. Numerous activities are found taking place in the rural areas of Peru. Many are the result of a specific intervention, designed and implemented towards

  16. Bayesian estimates of linkage disequilibrium

    Directory of Open Access Journals (Sweden)

    Abad-Grau María M

    2007-06-01

    Full Text Available Abstract Background The maximum likelihood estimator of D' – a standard measure of linkage disequilibrium – is biased toward disequilibrium, and the bias is particularly evident in small samples and rare haplotypes. Results This paper proposes a Bayesian estimation of D' to address this problem. The reduction of the bias is achieved by using a prior distribution on the pair-wise associations between single nucleotide polymorphisms (SNPs that increases the likelihood of equilibrium with increasing physical distances between pairs of SNPs. We show how to compute the Bayesian estimate using a stochastic estimation based on MCMC methods, and also propose a numerical approximation to the Bayesian estimates that can be used to estimate patterns of LD in large datasets of SNPs. Conclusion Our Bayesian estimator of D' corrects the bias toward disequilibrium that affects the maximum likelihood estimator. A consequence of this feature is a more objective view about the extent of linkage disequilibrium in the human genome, and a more realistic number of tagging SNPs to fully exploit the power of genome wide association studies.

  17. Pre-migratory differentiation of wild brown trout Salmo trutta into migrant and resident individuals

    DEFF Research Database (Denmark)

    Nielsen, Christian; Aarestrup, Kim; Nørum, Ulrik

    2003-01-01

    In February to March, wild brown trout Salmo trutta were captured by electrofishing in a natural watercourse (tributaries of the River Lille Aa, Denmark), individually tagged (Passive Integrated Transponders), and released. Representatives of the tagged brown trout were recaptured on the release......+,K+-ATPase analysis. Based on repetitive gill enzyme analysis in individual fish, a retrospective analysis of the rate of development in individual brown trout ultimately classified as migrants or residents was performed. Two months prior to migration, a bimodal morphological and physiological (gill Na...... a smolt-like appearance before the onset of migration and had higher rate of change of gill Na+,K+-ATPase activity than fish remaining residents. The rate of change of gill Na+,K+-ATPase activity was independent of the distance migrated to the trap (3-28 km). Thus in bimodal wild brown trout populations...

  18. Missing Linkages in California's Landscape [ds420

    Data.gov (United States)

    California Natural Resource Agency — The critical need for conserving landscape linkages first came to the forefront of conservation thinking in California in November 2000, when a statewide interagency...

  19. Missing Linkages in California's Landscape [ds420

    Data.gov (United States)

    California Department of Resources — The critical need for conserving landscape linkages first came to the forefront of conservation thinking in California in November 2000, when a statewide interagency...

  20. Markov chain Monte Carlo linkage analysis: effect of bin width on the probability of linkage.

    Science.gov (United States)

    Slager, S L; Juo, S H; Durner, M; Hodge, S E

    2001-01-01

    We analyzed part of the Genetic Analysis Workshop (GAW) 12 simulated data using Monte Carlo Markov chain (MCMC) methods that are implemented in the computer program Loki. The MCMC method reports the "probability of linkage" (PL) across the chromosomal regions of interest. The point of maximum PL can then be taken as a "location estimate" for the location of the quantitative trait locus (QTL). However, Loki does not provide a formal statistical test of linkage. In this paper, we explore how the bin width used in the calculations affects the max PL and the location estimate. We analyzed age at onset (AO) and quantitative trait number 5, Q5, from 26 replicates of the general simulated data in one region where we knew a major gene, MG5, is located. For each trait, we found the max PL and the corresponding location estimate, using four different bin widths. We found that bin width, as expected, does affect the max PL and the location estimate, and we recommend that users of Loki explore how their results vary with different bin widths.