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Sample records for salmo salar implied

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

    National Research Council Canada - National Science Library

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

    2007-01-01

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

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

    Science.gov (United States)

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

    2016-02-01

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

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

    OpenAIRE

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

    2015-01-01

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

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

    Science.gov (United States)

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

    2016-05-01

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

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

    Science.gov (United States)

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

    2003-01-01

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

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

    Science.gov (United States)

    Misimi, E; Erikson, U; Skavhaug, A

    2008-06-01

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

  7. 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.

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

    Science.gov (United States)

    McCartney, T.H.

    1976-01-01

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

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

    DEFF Research Database (Denmark)

    Kiilerich, Pia; Kristiansen, Karsten; Madsen, Steffen

    2007-01-01

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

  10. 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...

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

    NARCIS (Netherlands)

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

    2008-01-01

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

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

    Science.gov (United States)

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

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

    Science.gov (United States)

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

    2015-06-01

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

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

    OpenAIRE

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

    2011-01-01

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

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

    OpenAIRE

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

    2015-01-01

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

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

    OpenAIRE

    Papa, Laura

    2009-01-01

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

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

    Science.gov (United States)

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

    2017-01-01

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

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

    OpenAIRE

    Norrgård, Johnny R

    2011-01-01

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

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

    Science.gov (United States)

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

    2014-10-01

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

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

    Science.gov (United States)

    Salvanes, A G V

    2017-05-01

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

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

    DEFF Research Database (Denmark)

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

    2013-01-01

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

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

    DEFF Research Database (Denmark)

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

    1996-01-01

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

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

    DEFF Research Database (Denmark)

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

    1991-01-01

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

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

    NARCIS (Netherlands)

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

    2007-01-01

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

  5. 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...

  6. 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...

  7. 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...

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

    Science.gov (United States)

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

    2014-11-01

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

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

    Science.gov (United States)

    Engelbrecht Nielsen, M; Buchmann, K

    1997-01-01

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

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

    DEFF Research Database (Denmark)

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

    2013-01-01

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

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

    Science.gov (United States)

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

    2016-01-01

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

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

    Science.gov (United States)

    Rottiers, D.V.

    1993-01-01

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

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

    DEFF Research Database (Denmark)

    Lund, K.E.; Nielsen, Henrik Hauch

    2001-01-01

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

  14. 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....

  15. 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...

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

    DEFF Research Database (Denmark)

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

    2016-01-01

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

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

    Science.gov (United States)

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

    2014-11-01

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

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

    Science.gov (United States)

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

    2011-09-01

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

  19. 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.

  20. 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.

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

    Science.gov (United States)

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

    2012-01-01

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

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

    Directory of Open Access Journals (Sweden)

    Darren M Green

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

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

    Science.gov (United States)

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

    2011-03-16

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

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

    Science.gov (United States)

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

    2016-07-01

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

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

    Science.gov (United States)

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

    2017-04-01

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

  6. 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.

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

    Science.gov (United States)

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

    2013-08-15

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

  8. 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.

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

    Science.gov (United States)

    Ding, Z K; Xu, Y Q

    2002-08-01

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

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

    Science.gov (United States)

    Cipriano, R.C.

    2009-01-01

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

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

    Science.gov (United States)

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

    2015-09-08

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

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

    Science.gov (United States)

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

    2011-01-01

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

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

    Science.gov (United States)

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

    2017-10-24

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

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

    Science.gov (United States)

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

    2014-01-01

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

  15. 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.

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

    Science.gov (United States)

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

    2014-12-01

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

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

    Science.gov (United States)

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

    2008-01-01

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

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

    Science.gov (United States)

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

  19. 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)....

  20. 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...

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

    Science.gov (United States)

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

    2014-05-01

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

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

    Science.gov (United States)

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

    2013-11-01

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

  3. 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.

  4. 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.

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

    Directory of Open Access Journals (Sweden)

    Mónica B Betancor

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

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

    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.

  7. 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.

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

    Science.gov (United States)

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

    2011-01-01

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

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

    Science.gov (United States)

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

    2011-10-01

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

  10. 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.

  11. 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.

  12. Net ground speed of downstream migrating radio-tagged Atlantic salmon ( Salmo salar L.) and brown trout ( Salmo trutta L.) smolts in relation to environmental factors

    DEFF Research Database (Denmark)

    Aarestrup, Kim; Nielsen, C.; Koed, Anders

    2002-01-01

    tagged and released in the Danish River Lilleaa. The downstream migration of the different groups of fish was monitored by manual tracking and by three automatic listening stations. The downstream migration of radio tagged smolts of both species occurred concurrently with their untagged counterparts......The downstream migration of Atlantic salmon (Salmo salar L.) and sea trout smolt (S. trutta L.) was investigated using radio telemetry in the spring of 1999 and 2000. Forty wild sea trout smolts, 20 F1 sea trout smolts, 20 hatchery salmon smolts and 20 salmon smolts from river stockings were radio....... The diel migration pattern of the radio tagged smolts was predominantly nocturnal in both species. Wild sea trout smolt migrated significantly faster than both the F1 trout and the introduced salmon. There was no correlation between net ground speed, gill Na+, K+-ATPase activity or fish length in any...

  13. 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.

  14. 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

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

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    Tharangani K Herath

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

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

    Science.gov (United States)

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

    2009-01-01

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

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

    DEFF Research Database (Denmark)

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

    1998-01-01

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

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

    Science.gov (United States)

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

    2014-04-01

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

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

    Directory of Open Access Journals (Sweden)

    Gintarė Sauliutė

    2015-10-01

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

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

    Science.gov (United States)

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

    2016-02-01

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

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

    DEFF Research Database (Denmark)

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

    2012-01-01

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

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

    Science.gov (United States)

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

    2014-10-01

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

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

    DEFF Research Database (Denmark)

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

    2018-01-01

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

  5. A review of the likely effects of climate change on anadromous Atlantic salmon Salmo salar and brown trout Salmo trutta, with particular reference to water temperature and flow.

    Science.gov (United States)

    Jonsson, B; Jonsson, N

    2009-12-01

    The present paper reviews the effects of water temperature and flow on migrations, embryonic development, hatching, emergence, growth and life-history traits in light of the ongoing climate change with emphasis on anadromous Atlantic salmon Salmo salar and brown trout Salmo trutta. The expected climate change in the Atlantic is for milder and wetter winters, with more precipitation falling as rain and less as snow, decrease in ice-covered periods and frequent periods with extreme weather. Overall, thermal limits for salmonids are species specific. Scope for activity and growth and optimal temperature for growth increase with temperature to an optimal point before constrain by the oxygen content of the water. The optimal temperature for growth decreases with increasing fish size and varies little among populations within species, whereas the growth efficiency may be locally adapted to the temperature conditions of the home stream during the growth season. Indirectly, temperature influences age and size at smolting through its effect on growth. Time of spawning, egg hatching and emergence of the larvae vary with temperature and selective effects on time of first feeding. Traits such as age at first maturity, longevity and fecundity decrease with increasing temperature whilst egg size increases with temperature. Water flow influences the accessibility of rivers for returning adults and speed of both upstream and downstream migration. Extremes in water flow and temperature can decrease recruitment and survival. There is reason to expect a northward movement of the thermal niche of anadromous salmonids with decreased production and population extinction in the southern part of the distribution areas, migrations earlier in the season, later spawning, younger age at smolting and sexual maturity and increased disease susceptibility and mortality. Future research challenges are summarized at the end of the paper.

  6. 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

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

    Science.gov (United States)

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

    2009-01-01

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

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

    Science.gov (United States)

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

    2011-04-07

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

  9. 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.

  10. The culturable intestinal microbiota of triploid and diploid juvenile Atlantic salmon (Salmo salar - a comparison of composition and drug resistance

    Directory of Open Access Journals (Sweden)

    Cantas Leon

    2011-11-01

    Full Text Available Abstract Background With the increased use of ploidy manipulation in aquaculture and fisheries management this investigation aimed to determine whether triploidy influences culturable intestinal microbiota composition and bacterial drug resistance in Atlantic salmon (Salmo salar. The results could provide answers to some of the physiological differences observed between triploid and diploid fish, especially in terms of fish health. Results No ploidy effect was observed in the bacterial species isolated, however, triploids were found to contain a significant increase in total gut microbiota levels, with increases in Pseudomonas spp., Pectobacterium carotovorum, Psychrobacter spp., Bacillus spp., and Vibrio spp., (12, 42, 9, 10, and 11% more bacteria in triploids than diploids, respectively, whereas a decrease in Carnobacterium spp., within triploids compared to diploids was close to significant (8% more bacteria in diploids. With the exception of gentamicin, where no bacterial resistance was observed, bacterial isolates originating from triploid hosts displayed increased resistance to antibacterials, three of which were significant (tetracycline, trimethoprim, and sulphonamide. Conclusion Results indicate that triploidy influences both the community and drug resistance of culturable intestinal microbiota in juvenile salmon. These results demonstrate differences that are likely to contribute to the health of triploid fish and have important ramifications on the use of antibacterial drugs within aquaculture.

  11. 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.

  12. Paranucleospora theridion (Microsporidia) infection dynamics in farmed Atlantic salmon Salmo salar put to sea in spring and autumn.

    Science.gov (United States)

    Sveen, S; Øverland, H; Karlsbakk, E; Nylund, A

    2012-10-10

    The microsporidian Paranucleospora theridion (syn. Desmozoon lepeophtheirii) is a parasite of Atlantic salmon Salmo salar and also a hyperparasite of the salmon louse Lepeophtheirus salmonis. The parasite develops 2 types of spores in salmon, cytoplasmic spores in phagocytes and intranuclear spores in epidermal cells. The former type of development is assumed to be propagative (autoinfection), while the epidermal spores transfer the parasite to lice. Development in lice is extensive, with the formation of xenoma-like hypertrophic cells filled with microsporidian spores. We show that salmon are infected in the absence of lice, likely through waterborne spores that initiate infections in the gills. During summer and autumn the parasite propagates in the kidney, as evidenced by peaking normalised expression of P. theridion rRNA. Lice become infected during autumn, and develop extensive infections during winter. Lice mortality in winter and spring is likely responsible for a reservoir of spores in the water. Salmon transferred to sea in November (low temperature) did not show involvement of the kidney in parasite propagation and lice on such fish did not become infected. Apparently, low temperatures inhibit normal P. theridion development in salmon.

  13. Negligible differences in metabolism and thermal tolerance between diploid and triploid Atlantic salmon (Salmo salarL.).

    Science.gov (United States)

    Bowden, A J; Andrewartha, S J; Elliott, N G; Frappell, P B; Clark, T D

    2018-01-04

    The mechanisms that underlie thermal tolerance in aquatic ectotherms remain unresolved. Triploid fish have been reported to exhibit lower thermal tolerance than diploids, offering a potential model organism to better understand the physiological drivers of thermal tolerance. Here, we compared triploid and diploid juvenile Atlantic salmon ( Salmo salar ) in freshwater to investigate the proposed link between aerobic capacity and thermal tolerance. We measured specific growth rates (SGR) and resting (aerobic) metabolic rates (RMR) in freshwater at 3, 7 and 9 weeks of acclimation to either 10, 14 or 18°C. Additionally, maximum metabolic rates (MMR) were measured at 3 and 7 weeks of acclimation, and critical thermal maxima (CT max ) were measured at 9 weeks. Mass, SGR, and RMR differed between ploidies across all temperatures at the beginning of the acclimation period, but all three metrics converged between ploidies by week 7. Aerobic scope (MMR - RMR) remained consistent across ploidies, acclimation temperatures, and time. At 9 weeks, CT max was independent of ploidy, but correlated positively with acclimation temperature despite the similar aerobic scope between acclimation groups. Our findings suggest that acute thermal tolerance is not modulated by aerobic scope, and the altered genome of triploid Atlantic salmon does not translate to reduced thermal tolerance of juvenile fish in freshwater. © 2018. Published by The Company of Biologists Ltd.

  14. Atlantic salmon reovirus infection causes a CD8 T cell myocarditis in Atlantic salmon (Salmo salar L..

    Directory of Open Access Journals (Sweden)

    Aase B Mikalsen

    Full Text Available Heart and skeletal inflammation (HSMI of farmed Atlantic salmon (Salmo salar L. is a disease characterized by a chronic myocarditis involving the epicardium and the compact and spongious part of the heart ventricle. Chronic myositis of the red skeletal muscle is also a typical finding of HSMI. Piscine reovirus (PRV has been detected by real-time PCR from farmed and wild salmon with and without typical changes of HSMI and thus the causal relationship between presence of virus and the disease has not been fully determined. In this study we show that the Atlantic salmon reovirus (ASRV, identical to PRV, can be passaged in GF-1 cells and experimental challenge of naïve Atlantic salmon with cell culture passaged reovirus results in cardiac and skeletal muscle pathology typical of HSMI with onset of pathology from 6 weeks, peaking by 9 weeks post challenge. ASRV replicates in heart tissue and the peak level of virus replication coincides with peak of heart lesions. We further demonstrate mRNA transcript assessment and in situ characterization that challenged fish develop a CD8+ T cell myocarditis.

  15. The effect of stunning methods and season on muscle texture hardness in Atlantic salmon (Salmo salar L.).

    Science.gov (United States)

    Merkin, Grigory V; Stien, Lars Helge; Pittman, Karin; Nortvedt, Ragnar

    2014-06-01

    Commercially collected records of Atlantic salmon (Salmo salar L.) muscle texture hardness were used to evaluate the effect of slaughter procedures and seasonality on texture quality. A database collected by Marine Harvest® contained flesh hardness records of Atlantic salmon slaughtered at processing plants in Norway from summer 2010 to summer 2011. The fish were slaughtered either by (1) percussion followed by automated bleeding ("Percussive") or (2) live chilling with exposure to carbon dioxide (CO2 ) followed by manual severing gill arches and bleeding ("CO2 ") or (3) live chilling with exposure to CO2 followed by percussive stunning and at the end automated bleeding ("CO2 ·percussive"). Hardness in salmon muscle cutlets was measured in Newtons (N) by Materials Testing Machine Zwick 500N. The hardness in salmon varied significantly over the study period (P hardness (P < 0.05, mixed effect model), where percussion followed by automated bleeding resulted in the hardest value (24.0 ± 0.4 N) as compared with CO2 stunning (21.8 ± 0.2 N) and combination of CO2 and percussive stunning (23.1 ± 0.15 N). CO2 is suspected as a causal factor in accelerated postmortem softening of the salmon muscle. Commercial use of CO2 in combination with live chilling results in accelerated postmortem softening of the muscle tissue in salmon and should be avoided. © 2014 Institute of Food Technologists®

  16. A non-lethal method to estimate CYP1A expression in laboratory and wild Atlantic salmon (Salmo salar)

    Science.gov (United States)

    Rees, C.B.; McCormick, S.D.; Li, W.

    2005-01-01

    Expression of cytochrome P4501A (CYP1A) has been used as a biomarker for possible exposure to contaminants such as PCBs and dioxins in teleost fish. Using a quantitative reverse transcription-polymerase chain reaction (Q-RT-PCR) and a non-lethal gill biopsy, we estimated levels of CYP1A mRNA expression in Atlantic salmon (Salmo salar). Groups of ten Atlantic salmon juveniles (48–76 g) received an intraperitoneal injection of 50 μg g− 1 β-naphthoflavone (BNF) or vehicle. Their gill tissues were repeatedly sampled by non-lethal biopsies on day 0, 1, 2 and 7. Control fish expressed basal levels of CYP1A over the duration of sampling. BNF-treated salmon demonstrated similar levels of CYP1A to control fish at day 0 and higher levels over the course of each additional sampling point. Gill biopsies from wild salmon sampled from Millers River (South Royalston, Worcester County, MA, USA), known to contain PCBs, showed significantly higher CYP1A levels over an uncontaminated reference stream, Fourmile Brook (Northfield, Franklin County, MA, USA). We conclude that gill biopsies coupled with Q-RT-PCR analysis is a valuable tool in environmental assessment of wild Atlantic salmon populations and has the potential to be applied to other populations of fish as well.

  17. Sequential protein extraction as an efficient method for improved proteome coverage in larvae of Atlantic salmon (Salmo salar).

    Science.gov (United States)

    Nuez-Ortín, Waldo G; Carter, Chris G; Nichols, Peter D; Wilson, Richard

    2016-07-01

    Understanding diet- and environmentally induced physiological changes in fish larvae is a major goal for the aquaculture industry. Proteomic analysis of whole fish larvae comprising multiple tissues offers considerable potential but is challenging due to the very large dynamic range of protein abundance. To extend the coverage of the larval phase of the Atlantic salmon (Salmo salar) proteome, we applied a two-step sequential extraction (SE) method, based on differential protein solubility, using a nondenaturing buffer containing 150 mM NaCl followed by a denaturing buffer containing 7 M urea and 2 M thiourea. Extracts prepared using SE and one-step direct extraction were characterized via label-free shotgun proteomics using nanoLC-MS/MS (LTQ-Orbitrap). SE partitioned the proteins into two fractions of approximately equal amounts, but with very distinct protein composition, leading to identification of ∼40% more proteins than direct extraction. This fractionation strategy enabled the most detailed characterization of the salmon larval proteome to date and provides a platform for greater understanding of physiological changes in whole fish larvae. The MS data are available via the ProteomeXchange Consortium PRIDE partner repository, dataset PXD003366. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Consistency of standard metabolic rate in relation to life history strategy of juvenile Atlantic salmon Salmo salar.

    Science.gov (United States)

    Seppänen, Eila; Piironen, Jorma; Huuskonen, Hannu

    2010-06-01

    Temporal consistency of relative standard metabolic rate (rSMR) of individual Atlantic salmon Salmo salar juveniles in three stocks was investigated. The stocks differed in their geographical origin and natal habitat (fresh water, brackish water, seawater). Oxygen consumption measurements of hatchery-reared fish hatched in February 2005 were conducted three times: in early spring 2006, in autumn 2006, and in late spring 2007. The results partly disagreed and partly agreed with earlier studies, in which temporal consistency of SMR in juvenile salmonids have been addressed. In the first period from early spring to autumn, no correlation between rSMR statuses of individuals was found whereas in the second period from autumn to late spring, fish were mainly observed to maintain their relative SMR level indicating a significant repeatability of individual rSMR status over the latter period. Furthermore, a relationship between rSMR status and life history strategy was found: post-smolts and smolts had higher SMR than non-smolts. Copyright 2010 Elsevier Inc. All rights reserved.

  19. 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.

  20. Somatosensory evoked potentials in the telencephalon of Atlantic salmon (Salmo salar) following galvanic stimulation of the tail.

    Science.gov (United States)

    Nordgreen, Janicke; Horsberg, Tor Einar; Ranheim, Birgit; Chen, Andrew C N

    2007-12-01

    Electric activity in the brain which is time-locked to a given stimulation of the somatosensory system can be recorded as a somatosensory evoked potential (SEP). We investigated whether a galvanic stimulation of the tail base in Atlantic salmon (Salmo salar) would elicit a SEP in the telencephalon. The telencephalon is central in learning and memory, and activity here may be a prerequisite for processing of external stimuli on a cognitive or emotional level. Anaesthetized salmon (n = 11) were subjected to craniotomy and a recording electrode was inserted into the telencephalon. The fish were given stimulations of four intensities, i.e., 2, 5, 10 and 20 mA. A SEP was elicited in the contralateral dorsal telencephalon for all intensities. This result agrees with findings in other fish species. Furthermore, there was a significant difference between the maximum peak amplitude and mean amplitude of the SEP elicited by putative non-noxious (2 mA) and putative noxious (20 mA) stimulation intensities (P stimulation intensities also tend to introduce longer-latencies components in the SEP. The results added to the body of literature indicates that the exteroceptive senses are represented by processing within the telencephalon of the fish.

  1. 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.

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

    Science.gov (United States)

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

    2010-09-01

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

  3. Carbon monoxide as stunning/killing method on farmed Atlantic salmon (Salmo salar): effects on lipid and cholesterol oxidation.

    Science.gov (United States)

    Secci, Giulia; Serra, Andrea; Concollato, Anna; Conte, Giuseppe; Mele, Marcello; Olsen, Rolf E; Parisi, Giuliana

    2016-05-01

    Carbon monoxide (CO) has been recently utilized as a new stunning/killing procedure for Atlantic salmon (Salmo salar). Its effects on lipid and cholesterol oxidation of farmed Atlantic salmon fillets were evaluated at two times of refrigerated (2.5 °C) storage, T0 (64 h after death) and T14 (14 days from T0). The use of CO was compared with the commonly utilized percussion (P) method. Fatty acid profile, primary (conjugated dienes) and secondary (TBARS) oxidation products, cholesterol oxidation products (COPs) and carotenoids were unaffected by the killing method. Despite the low oxidative status of lipid (0.66 and 0.60 mg malondialdehyde kg(-1) muscle in P and CO fish respectively), cholesterol was found to be highly oxidized (0.17 and 0.13 mg COPs kg(-1) ). Storage significantly affected oxidative stability of fish muscle by increasing oxidation products. Interestingly, TBARS content doubled while the increase for COPs was not homogeneous: α- and β-epoxycholesterol increased by 25%, whereas triol and 7-ketocholesterol increased by 48 and 62% respectively. The quality of salmon fillets just after slaughtering and after 14 days of refrigerated storage at 2.5 °C did not change, irrespective of the killing method adopted, suggesting that the CO method may be applied without any detrimental effect on the quality of fish fillets. © 2015 Society of Chemical Industry. © 2015 Society of Chemical Industry.

  4. The effect of light on the settlement of the salmon louse, Lepeophtheirus salmonis, on Atlantic salmon, Salmo salar L.

    Science.gov (United States)

    Browman, H I; Boxaspen, K; Kuhn, P

    2004-12-01

    The salmon louse, Lepeophtheirus salmonis, is an ectoparasitic copepod that infests both wild and farmed salmonid fish. Salmon lice are a major disease problem in the farming of Atlantic salmon, Salmo salar L., and the possibility of salmon lice playing a role in the decline of wild anadromous stocks has also been raised. Lepeophtheirus salmonis can detect a range of stimuli (pressure/moving water, chemicals and light) in the external environment. However, the response thresholds to various stimuli, and the spatial and temporal scales over which they operate in the context of host location, are largely unknown. In this context, we attempted to determine whether salmon lice copepodids settle onto hosts more effectively, or at different locations on the fish's body, under different qualities of light. Lice settlement trials were conducted under three lighting conditions; L1: unpolarized under ultraviolet A (UVA)-through visible; L2: unpolarized without UVA (control); L3: 100% linearly polarized without UVA. A dark control was also conducted. No statistically significant difference in lice settlement was found. While changes in light intensity are involved in host detection at spatial scales on the order of metres, the results presented here suggest that it is not the primary sensory modality underlying host location at smaller spatial scales (cm to mm).

  5. 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.

  6. Histological changes in intestine of Atlantic salmon (Salmo salar L.) following in vitro exposure to pathogenic and probiotic bacterial strains.

    Science.gov (United States)

    Ringø, E; Salinas, I; Olsen, R E; Nyhaug, A; Myklebust, R; Mayhew, T M

    2007-04-01

    Furunculosis and vibriosis are diseases that cause severe economic losses in the fish-farming industry. The foregut of the Atlantic salmon (Salmo salar L.) was exposed in vitro to two fish pathogens, Aeromonas salmonicida (causative agent of furunculosis) and Vibrio anguillarum (causative agent of vibriosis), and to one probiotic strain, Carnobacterium divergens, at 6 x 10(4) or 6 x 10(6) viable bacteria per milliliter. Histological changes following bacterial exposure were assessed by light and electron microscopy. Control samples (foregut exposed to Ringer's solution only) and samples exposed only to C. divergens had a similar appearance to intact intestinal mucosal epithelium, with no signs of damage. However, exposure of the foregut to the pathogenic bacteria resulted in damaged epithelial cells, cell debris in the lumen, and disorganization of the microvilli. Co-incubation of the foregut with a pathogen and C. divergens did not reverse the damaging effects caused by the pathogen, although these were alleviated when probiotic bacteria were used. Based on these results, we suggest that the probiotic bacterium, C. divergens, is able to prevent, to some extent, pathogen-induced damage in the Atlantic salmon foregut.

  7. 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.

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

    Science.gov (United States)

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

    2016-06-01

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

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

    Science.gov (United States)

    Verspoor, E; Knox, D; Marshall, S

    2016-12-01

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

  10. Attempt to validate breakpoint MIC values estimated from pharmacokinetic data obtained during oxolinic acid therapy of winter ulcer disease in Atlantic salmon ( Salmo salar )

    DEFF Research Database (Denmark)

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

    2004-01-01

    Concentrations of oxolinic acid (OXA) were measured in the plasma, muscle, liver, and kidney of 48 Atlantic salmons (Salmo salar) 1 day after the end of an oral administration. OXA was administered over a period of 13 days to control an outbreak of winter ulcer disease in a commercial marine farm....... On the basis of their behaviour, the fish were classified as healthy (n=18), moribund (n=20), or dead (n=10). There was a dramatic difference in the OXA concentrations in the healthy fish and those classified as moribund or dead. There was no evidence of bacterial infection in the 18 healthy fish, all of which...

  11. Comparison of two pre-enrichments broths for recovering Listeria spp. from salmon (Salmo salar) and salmon-trout (Oncorhynchus mykiss)

    OpenAIRE

    Vaz-Velho,Manuela; Duarte, Gabriela; Gibbs, Paul

    2001-01-01

    Low levels of occurrence of Listeria spp. in fresh salmon (Salmo_salar ) and salmon-trout (Oncorhynchus mykiss), may be related to the selectivity of the pre-enrichment broth recommended by ISO 11290-1. The purpose of this study was to compare the abilities of Fraser base (without supplements) and 0.1% (w/v) peptone water for recovering Listeria spp. from the fresh fish samples. Fifty-six fish were swabbed and the swabs placed in Fraser base and in 0.1% (w/v) peptone water. Samples were a...

  12. Quality of raw and smoked fillets from clinically healthy Atlantic salmon, Salmo salar L., following an outbreak of pancreas disease (PD)

    DEFF Research Database (Denmark)

    Taksdal, T.; Wiik‐Nielsen, J.; Birkeland, S.

    2012-01-01

    Pancreas disease (PD) is a viral disease of farmed salmonid fish, which causes huge economic losses. Pathological changes in skeletal muscle, pancreas and heart are hallmarks of PD. Stakeholders in the fish‐smoking industry have claimed that fillets from PD‐affected Atlantic salmon, Salmo salar L...... provided a paler raw fillet and a yellowish and harder cold‐smoked fillet than normal. PD had no significant effect on fillet gaping, bacteriological quality or off‐odour development during storage. An unexpected finding was a significant subendocardial fibrosis in 23% of the PD‐affected fish. The latter...

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

    Science.gov (United States)

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

    2012-08-01

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

  14. 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.

  15. Expression of Vibrio salmonicida virulence genes and immune response parameters in experimentally challenged Atlantic salmon (Salmo salar L.

    Directory of Open Access Journals (Sweden)

    Ane Mohn Bjelland

    2013-12-01

    Full Text Available The Gram-negative bacterium Vibrio salmonicida is the causative agent of cold-water vibriosis (CV, a hemorrhagic septicemia that primarily affects farmed Atlantic salmon (Salmo salar L.. The mechanisms of disease development, host specificity and adaptation, as well as the immunogenic properties of V. salmonicida are largely unknown. Therefore, to gain more knowledge on the pathogenesis of CV, 90 Atlantic salmon parr were injected intraperitonellay with 6 x 106 CFU of V. salmonicida LFI1238. Samples from blood and spleen tissue were taken at different time points throughout the challenge for gene expression analysis by two-step reverse transcription quantitative real-time polymerase chain reaction. Out of a panel of six housekeeping genes, accD, gapA and 16S rDNA were found to be the most suitable references for expression analysis in Vibrio salmonicida. The bacterial proliferation during challenge was monitored based on the expression of the 16S rRNA encoding gene. Before day 4, the concentrations of V. salmonicida in blood and spleen tissue demonstrated a lag phase. From day 4, the bacterial proliferation was exponential. The expression profiles of eight genes encoding potential virulence factors of V. salmonicida were studied. Surprisingly, all tested virulence genes were generally highest expressed in broth cultures compared to the in vivo samples. We hypothesize that this general muting of gene expression in vivo may be a strategy for V. salmonicida to hide from the host immune system. To further investigate this hypothesis, the expression profiles of eight genes encoding innate immune factors were analyzed. The results demonstrated a strong and rapid, but short-lasting innate immune response against V. salmonicida. These results suggest that the bacterium possesses mechanisms that inhibit and/or resist the salmon innate immune system until the host becomes exhausted of fighting the on-going and eventually overwhelming infection.

  16. 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.

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

    Directory of Open Access Journals (Sweden)

    Christian De Santis

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

  18. Population dynamics of Vibrio and Pseudomonas species isolated from farmed Tasmanian Atlantic salmon (Salmo salar L.): a seasonal study.

    Science.gov (United States)

    Hatje, Eva; Neuman, Christina; Stevenson, Hollie; Bowman, John P; Katouli, Mohammad

    2014-11-01

    Vibrio and Pseudomonas species have been shown to be part of the normal microbiota of Atlantic salmon (Salmo salar L.), with some strains causing disease in fish. The factors affecting their prevalence and persistence in the salmon gut, however, have not been well studied. In this study, we collected 340 Vibrio and 150 Pseudomonas isolates from the hindgut of farmed Tasmanian Atlantic salmon, fed with two commercially available diets. Samples were collected every 6-8 weeks between July 2011 and May 2012. Isolates from selective agar were initially identified using biochemical tests and confirmed using genus-specific primers and 16S ribosomal RNA (16S rRNA) sequencing. Random amplified polymorphic DNA (RAPD) PCR was used to type both Pseudomonas and Vibrio; the latter was further typed using a biochemical fingerprinting method (PhP-RV plates). We observed low species diversity with strains comprising Vibrio ichthyoenteri/Vibrio scophthalmi, Vibrio crassostreae/Vibrio splendidus, Aliivibrio finisterrensis, Photobacterium phosphoreum and Pseudomonas fragi. Out of 340 Vibrio isolates, 238 (70 %) belonged to 21 clonal types and were found predominantly during summer when water temperatures reached 15 to 21 °C. Of these, the four major clonal types were found in multiple samples (70 %). P. fragi, on the other hand, was only found during the colder water temperatures and belonged to 18 clonal types. The presence of both groups of bacteria and their clonal types were independent of the fish diets used, suggesting that the water temperature was the main factor of the prevalence and persistence of these bacteria in the gut of Atlantic salmon.

  19. Natural infection of Atlantic salmon (Salmo salar L.) with salmonid alphavirus 3 generates numerous viral deletion mutants.

    Science.gov (United States)

    Petterson, Elin; Stormoen, Marit; Evensen, Øystein; Mikalsen, Aase B; Haugland, Øyvind

    2013-09-01

    Salmon pancreas disease virus (SPDV) also referred to as salmonid alphavirus (SAV) is a virus causing pancreas disease in Atlantic salmon (Salmo salar L.) and rainbow trout (Oncorhynchus mykiss). Although the virus causes an economically important disease, relatively few full-length genome sequences of SAV strains are currently available. Here, we report full-length genome sequences of nine SAV3 strains from sites farming Atlantic salmon geographically spread along the Norwegian coastline. The virus genomes were sequenced directly from infected heart tissue, to avoid culture selection bias. Sequence analysis confirmed a high level of sequence identity within SAV3 strains, with a mean nucleotide diversity of 0.11 %. Sequence divergence was highest in 6K and E2, while lowest in the capsid protein and the non-structural proteins (nsP4 and nsP2). This study reports for the first time that numerous defective viruses containing genome deletions are generated during natural infection with SAV. Deletions occurred in all virus strains and were not distributed randomly throughout the genome but instead tended to aggregate in certain areas. We suggest imprecise homologous recombination as an explanation for generation of defective viruses with genome deletions. The presence of such viruses, provides a possible explanation for the difficulties in isolating SAV in cell culture. Primary virus isolation was successfully achieved for only two of eight strains, despite extensive attempts using three different cell lines. Both SAV isolates were easily propagated further and concomitant viral deletion mutants present in clinically infected heart tissue were maintained following serial passage in CHH-1 cells.

  20. 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.

  1. 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.

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

    Science.gov (United States)

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

    2013-09-24

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

  3. Social hierarchies, growth and brain serotonin metabolism in Atlantic salmon (Salmo salar) kept under commercial rearing conditions.

    Science.gov (United States)

    Cubitt, K Fiona; Winberg, Svante; Huntingford, Felicity A; Kadri, Sunil; Crampton, Vivian O; Overli, Oyvind

    2008-07-05

    Monitoring social interactions between individuals in large, high-density groups poses several challenges. Here we demonstrate that relative concentrations of serotonin (5-Hydroxytryptamine, 5-HT) and its principal catabolite 5-Hydroxyindoleacetic acid (5-HIAA) in brain tissue of individual fish reflect social organisation in large groups of farmed Atlantic salmon. In the central nervous system of vertebrates, the monoamine neurotransmitter/neuromodulator 5-HT is critical for maintaining adaptive physiological, cognitive and emotional processes. In both teleost fish and mammals it has previously been shown that social interactions in small groups lead to elevated 5-HT release and/or metabolism in subordinate individuals, as indicated by the 5-HIAA/5-HT concentration ratio. In the current study, evidence is presented of non-linear dominance hierarchies in farmed Atlantic salmon (Salmo salar) kept at high rearing densities. The physiological effect of these hierarchies was decreased when food resources were abundant, although some subordinate fish still showed altered brain serotonergic activity and failed to grow even feed was available in excess. The largest effect of decreased feed rations was seen in fish of intermediate size, where competition appeared to increase with reduced access to feed. The largest individuals in each rearing unit showed low 5-HIAA/5-HT ratios independent of feeding regime. A novel observation, with respect to previous studies, was that elevated brain 5-HIAA/5-HT ratios resulted from decreased 5-HT concentrations rather than elevated 5-HIAA in small fish. Thus, in light of the serotonin deficit hypothesis of depression, it cannot be excluded that social stress is important for animal welfare even in large, relatively homogenous groups of animals reared in captivity.

  4. Metabolic effects of amoebic gill disease (AGD) and chloramine-T exposure in seawater-acclimated Atlantic salmon Salmo salar.

    Science.gov (United States)

    Leef, M J; Harris, J O; Powell, M D

    2007-10-31

    Our aim was to determine possible metabolic effects amoebic gill disease (AGD) on Atlantic salmon Salmo salar. Standard (R(S)) and routine (R(ROU)) metabolic rates were evaluated by continually measuring oxygen consumption in 2 independent tanks of fish (18.69 +/- 1.01 kg m(-3), mean +/- SE). Active metabolic rate (R(ACT)) and metabolic scope (R(ACT) - R(S)) were assessed using a chasing protocol and determined at 3 time periods: (1) pre-infection, (2) 3 d post-infection, and (3) 2 d post-treatment. On Day 3 of the study, the fish were infected with amoebae isolated from the gills of AGD-affected salmon (2300 cells l(-1)). No significant elevations in R(ACT) or metabolic scope were detected 3 d post-infection and 2 d post-treatment; however, significant elevations in R(S) and R(ROU) were detected 3 d post-infection and 2 d post-treatment. Assessment of R(ROU) data, especially for the light period, also indicated a rise in oxygen consumption rate over the course of the experiment. Treatment of AGD-affected Atlantic salmon with chloramine-T (CL-T) appeared to briefly mitigate the rise in R(S), as there was a 30% drop (though non-significant) in R(S) following treatment. Despite this, R(S) continued the upward trend 1 d following treatment. These results suggest that over the course of AGD development, R(S) in Atlantic salmon increases. Therefore, considering the physical conditions which constrain R(ACT), we expect that metabolic scope would become compromised in fish more heavily affected with AGD. Treatment with CL-T shows promise for mitigating the respiratory effects of AGD and potentially minimising the loss of metabolic scope.

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

    Energy Technology Data Exchange (ETDEWEB)

    Bakke, Marit Jorgensen [Department of Pharmacology and Toxicology, Norwegian School of Veterinary Science, PO Box 8146 Dep., N-0033 Oslo (Norway); Horsberg, Tor Einar [Department of Pharmacology and Toxicology, Norwegian School of Veterinary Science, PO Box 8146 Dep., N-0033 Oslo (Norway)], E-mail: tor.e.horsberg@veths.no

    2007-11-30

    Neurotoxins from algal blooms have been reported to cause mortality in a variety of species, including sea birds, sea mammals and fish. Farmed fish cannot escape harmful algal blooms and their potential toxins, thus they are more vulnerable for exposure than wild stocks. Sublethal doses of the toxins are likely to affect fish behaviour and may impair cognitive abilities. In the present study, changes in the metabolic activity in different parts of the Atlantic salmon (Salmo salar) brain involved in central integration and cognition were investigated after exposure to sublethal doses of three algal-produced neurotoxins; saxitoxin (STX), brevetoxin (BTX) and domoic acid (DA). Fish were randomly selected to four groups for i.p. injection of saline (control) or one of the neurotoxins STX (10 {mu}g STX/kg bw), BTX (68 {mu}g BTX/kg bw) or DA (6 mg DA/kg bw). In addition, {sup 14}C-2-deoxyglucose was i.m. injected to measure brain metabolic activity by autoradiography. The three regions investigated were telencephalon (Tel), optic tectum (OT) and cerebellum (Ce). There were no differences in the metabolic activity after STX and BTX exposure compared to the control in these regions. However, a clear increase was observed after DA exposure. When the subregions with the highest metabolic rate were pseudocoloured in the three brain regions, the three toxins caused distinct differences in the respective patterns of metabolic activation. Fish exposed to STX displayed similar patterns as the control fish, whereas fish exposed to BTX and DA showed highest metabolic activity in subregions different from the control group. All three neurotoxins affected subregions that are believed to be involved in cognitive abilities in fish.

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

    Science.gov (United States)

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

    2017-11-01

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

  7. Effects of crowding on blood constituents and flesh quality variables in Atlantic salmon (Salmo salar L.) Efecto del confinamiento sobre las variables sanguíneas y calidad de carne de Salmón Atlántico (Salmo salar L.)

    OpenAIRE

    MC Gatica; GE Monti; TG Knowles; CB Gallo

    2010-01-01

    The effects of anaesthesia (as a control treatment) and controlled crowding, with its concomitant low oxygen level, on harvest size salmon (Salmo salar) were compared in terms of blood constituents and flesh quality variables, at 0, 1, 4, 7 and 10 days post-mortem. Fish were held in tanks in triplicate and were sampled after anaesthetizing with AQUI-S® and after crowding for one hour. Eighteen fish from each treatment were stunned, blood sampled from the posterior aorta and the fish bled by g...

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2003-10-08

    Atlantic salmon (Salmo salar L.) parr were fed for 4 months on fish meal based diets supplemented with mercuric chloride (0, 10, or 100 mg Hg kg{sup -1} DW) or methylmercury chloride (0, 5, or 10 mg Hg kg{sup -1} DW) to assess the effects of inorganic (Hg) and organic dietary mercury on brain lipid peroxidation and neurotoxicity. Lipid peroxidative products, endogenous anti oxidant enzymes, brain histopathology, and overall behaviour were measured. Methylmercury accumulated significantly in the brain of fish fed 5 or 10 mg kg{sup -1} by the end of the experiment, and inorganic mercury accumulated significantly in the brain only at 100 mg kg{sup -1} exposure levels. No mortality or growth reduction was observed in any of the exposure groups. Fish fed 5 mg kg{sup -1} methylmercury had a significant increase (2-fold) in the antioxidant enzyme super oxide dismutase (SOD) in the brain. At dietary levels of 10 mg kg{sup -1} methylmercury, a significant increase (7-fold) was observed in lipid peroxidative products (thiobarbituric acid reactive substances, TBARS) and a subsequently decrease (1.5-fold) in anti oxidant enzyme activity (SOD and glutathione peroxidase, GSH-Px). Fish fed 10 mg kg{sup -1} methylmercury also had pathological damage (vacoulation and necrosis), significantly reduced neural enzyme activity (5-fold reduced monoamine oxidase, MAO, activity), and reduced overall post-feeding activity behaviour. Pathological injury started in the brain stem and became more widespread in other areas of the brain at higher exposure levels. Fish fed 100 mg Hg kg{sup -1} inorganic mercury had significant reduced neural MAO activity and pathological changes (astrocyte proliferation) in the brain, however, neural SOD and GSH-Px enzyme activity, lipid peroxidative products (TBARS), and post feeding behaviour did not differ from controls. Compared with other organs, the brain is particular susceptible for dietary methylmercury induced lipid peroxidative stress at relative low

  9. Annotated Expressed Sequence Tags (ESTs from pre-smolt Atlantic salmon (Salmo salar in a searchable data resource

    Directory of Open Access Journals (Sweden)

    Ruden Torgeir A

    2007-07-01

    Full Text Available Abstract Background To identify as many different transcripts/genes in the Atlantic salmon genome as possible, it is crucial to acquire good cDNA libraries from different tissues and developmental stages, their relevant sequences (ESTs or full length sequences and attempt to predict function. Such libraries allow identification of a large number of different transcripts and can provide valuable information on genes expressed in a particular tissue at a specific developmental stage. This data is important in constructing a microarray chip, identifying SNPs in coding regions, and for future identification of genes in the whole genome sequence. An important factor that determines the usefulness of generated data for biologists is efficient data access. Public searchable databases play a crucial role in providing such service. Description Twenty-three Atlantic salmon cDNA libraries were constructed from 15 tissues, yielding nearly 155,000 clones. From these libraries 58,109 ESTs were generated, of which 57,212 were used for contig assembly. Following deletion of mitochondrial sequences 55,118 EST sequences were submitted to GenBank. In all, 20,019 unique sequences, consisting of 6,424 contigs and 13,595 singlets, were generated. The Norwegian Salmon Genome Project Database has been constructed and annotation performed by the annotation transfer approach. Annotation was successful for 50.3% (10,075 of the sequences and 6,113 sequences (30.5% were annotated with Gene Ontology terms for molecular function, biological process and cellular component. Conclusion We describe the construction of cDNA libraries from juvenile/pre-smolt Atlantic salmon (Salmo salar, EST sequencing, clustering, and annotation by assigning putative function to the transcripts. These sequences represents 97% of all sequences submitted to GenBank from the pre-smoltification stage. The data has been grouped into datasets according to its source and type of annotation. Various data

  10. 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.

  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. Evaluación de la alimentación de Salmo salar en piscicultura, utilizando dispensadores automáticos

    Directory of Open Access Journals (Sweden)

    A. Mardones

    2013-09-01

    Full Text Available El cultivo de salmones, específicamente Salmo salar es una industria que genera aspectos básicos y aplicados destinado a su producción intensiva. En este contexto, el presente estudio evaluó el crecimiento de salmones en cultivo bajo tres condiciones, alimentador manual con alimentación diurna, con alimentación nocturna, y día y noche, y un grupo control con alimentación manual a saciedad. Se encontró menor crecimiento en el grupo control respecto a los tres grupos alimentados con alimentador artificial. Estos resultados concuerdan con las descripciones de la literatura para el hemisferio norte.

  13. 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...

  14. Histochemical demonstration of mercury in the olfactory system of salmon (Salmo salar L.) following treatments with dietary methylmercuric chloride and dissolved mercuric chloride

    DEFF Research Database (Denmark)

    Baatrup, E; Døving, K B

    1991-01-01

    in the olfactory rosettes and their nerves. Tissue sections from the rosettes and olfactory nerves were subjected to autometallographic silver enhancement, thereby rendering mercury deposits visible for light and electron microscopy. Microscopic analysis demonstrated an intense and comprehensive Hg deposition......The deposition of organic and inorganic mercury compounds was studied histochemically in the salmon (Salmo salar L.) olfactory system. One group of salmon was given fodder pellets containing methylmercuric chloride (CH3HgCl, 99 micrograms Hg/g) for 4 weeks. Other groups of fish were exposed...... to dissolved mercuric chloride (HgCl2, 270 micrograms Hg/liter) for 2, 6, and 12 hr, respectively. In both series of experiments, the radioisotope 203Hg was included in order to determine the accumulation of mercury in the olfactory system. Gamma-spectrometry showed that both mercury compounds accumulated...

  15. 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.

  16. The effect of Cu (II) on the electro-olfactogram (EOG) of the Atlantic salmon (Salmo salar L) in artificial freshwater of varying inorganic carbon concentrations

    DEFF Research Database (Denmark)

    Winberg, S; Bjerselius, R; Baatrup, E

    1993-01-01

    The effect of inorganic copper species was studied by recording the receptor potential, electro-olfactogram (EOG), from the olfactory epithelium of Atlantic salmon (Salmo salar L). In a series of experiments, the olfactory organ was irrigated with aqueous copper solutions with concentrations...... of the free cupric ion (Cu2+) ranging from 0.2 to 9.7 microM. The diverse copper species were created by varying the amount of bicarbonate (NaHCO3) in artificial freshwater solutions of equal total copper concentrations. In general, these copper solutions induced a slow depolarization of the baseline followed...... by a hyperpolarization. The amplitudes of these variations in baseline potentials increased with increasing concentrations of Cu2+ ion, i.e., decreasing concentrations of NaHCO3. Stimulating the olfactory epithelium with L-alanine during the copper exposure evoked atypical EOG responses. The amplitudes and form...

  17. Expression of gill vacuolar-type H+-ATPase B subunit, and Na+, K+-ATPase alpha- and beta- subunit messenger RNAs in smolting Salmo salar

    DEFF Research Database (Denmark)

    Seidelin, Michel; Madsen, Steffen; Cutler, Christopher P

    2001-01-01

    Changes in gill vacuolar-type H+-ATPase B subunit, and Na+,K+-ATPase alpha and beta subunit mRNA expression were examined during the course of smoltification in Salmo salar. We cloned and sequenced cDNA fragments of S. salar gill i) vacuolar-type H+-ATPase (V-H+-ATPase) B subunit, ii) Na......+,K+-ATPase alpha (1) subunit, and iii) Na+,K+-ATPase beta (1) subunit, and used these as Northern blotting probes. During smoltification, the salmon showed a typical increase in gill Na+,K+-ATPase activity and improved hypo-osmoregulatory ability as judged by their ability to regulate plasma [Cl-] in a 24-hr...... seawater challenge test (35 ppt). Gill Na+,K+-ATPase alpha (1) and beta (1) subunit mRNA levels were regulated at a constant ratio during smoltification. Both transcripts were elevated during the build-up of gill Na+,K+-ATPase activity, underlining the importance of increased mRNA levels for increased...

  18. 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.

  19. Genetic heterogeneity of within-family variance of body weight in Atlantic salmon (Salmo salar).

    Science.gov (United States)

    Sonesson, Anna K; Odegård, Jørgen; Rönnegård, Lars

    2013-10-17

    Canalization is defined as the stability of a genotype against minor variations in both environment and genetics. Genetic variation in degree of canalization causes heterogeneity of within-family variance. The aims of this study are twofold: (1) quantify genetic heterogeneity of (within-family) residual variance in Atlantic salmon and (2) test whether the observed heterogeneity of (within-family) residual variance can be explained by simple scaling effects. Analysis of body weight in Atlantic salmon using a double hierarchical generalized linear model (DHGLM) revealed substantial heterogeneity of within-family variance. The 95% prediction interval for within-family variance ranged from ~0.4 to 1.2 kg2, implying that the within-family variance of the most extreme high families is expected to be approximately three times larger than the extreme low families. For cross-sectional data, DHGLM with an animal mean sub-model resulted in severe bias, while a corresponding sire-dam model was appropriate. Heterogeneity of variance was not sensitive to Box-Cox transformations of phenotypes, which implies that heterogeneity of variance exists beyond what would be expected from simple scaling effects. Substantial heterogeneity of within-family variance was found for body weight in Atlantic salmon. A tendency towards higher variance with higher means (scaling effects) was observed, but heterogeneity of within-family variance existed beyond what could be explained by simple scaling effects. For cross-sectional data, using the animal mean sub-model in the DHGLM resulted in biased estimates of variance components, which differed substantially both from a standard linear mean animal model and a sire-dam DHGLM model. Although genetic differences in canalization were observed, selection for increased canalization is difficult, because there is limited individual information for the variance sub-model, especially when based on cross-sectional data. Furthermore, potential macro

  20. 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

  1. 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

  2. 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

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

    Science.gov (United States)

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

    2013-09-27

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

  4. 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.

  5. A critical life stage of the Atlantic salmon Salmo salar: behaviour and survival during the smolt and initial post-smolt migration.

    Science.gov (United States)

    Thorstad, E B; Whoriskey, F; Uglem, I; Moore, A; Rikardsen, A H; Finstad, B

    2012-07-01

    The anadromous life cycle of Atlantic salmon Salmo salar involves long migrations to novel environments and challenging physiological transformations when moving between salt-free and salt-rich waters. In this article, (1) environmental factors affecting the migration behaviour and survival of smolts and post-smolts during the river, estuarine and early marine phases, (2) how behavioural patterns are linked to survival and (3) how anthropogenic factors affect migration and survival are synthesized and reviewed based on published literature. The timing of the smolt migration is important in determining marine survival. The timing varies among rivers, most likely as a consequence of local adaptations, to ensure sea entry during optimal periods. Smolts and post-smolts swim actively and fast during migration, but in areas with strong currents, their own movements may be overridden by current-induced transport. Progression rates during the early marine migration vary between 0.4 and 3.0 body lengths s(-1) relative to the ground. Reported mortality is 0.3-7.0% (median 2.3) km(-1) during downriver migration, 0.6-36% (median 6.0) km(-1) in estuaries and 0.3-3.4% (median 1.4) km(-1) in coastal areas. Estuaries and river mouths are the sites of the highest mortalities, with predation being a common cause. The mortality rates varied more among studies in estuaries than in rivers and marine areas, which probably reflects the huge variation among estuaries in their characteristics. Behaviour and survival during migration may also be affected by pollution, fish farming, sea lice Lepeophtheirus salmonis, hydropower development and other anthropogenic activities that may be directly lethal, delay migration or have indirect effects by inhibiting migration. Total mortality reported during early marine migration (up to 5-230 km from the river mouths) in the studies available to date varies between 8 and 71%. Hence, the early marine migration is a life stage with high mortalities, due

  6. 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.

  7. Water quality limits for Atlantic salmon (Salmo salar L.) exposed to short term reductions in pH and increased aluminum simulating episodes

    Science.gov (United States)

    Kroglund, F.; Rosseland, B. O.; Teien, H.-C.; Salbu, B.; Kristensen, T.; Finstad, B.

    2008-03-01

    Acidification has caused the loss or reduction of numerous Atlantic salmon (Salmo salar L.) populations on both sides of the North Atlantic. Acid deposition peaked in the 1980's and resulted in both chronically and episodically acidified rivers. At present, water quality is improving in all affected rivers due to reduced acid deposition. However, spring snow melt, heavy rainfall and sea salt episodes can still cause short term drops in pH and elevated concentrations of bioavailable aluminum. Technical malfunction in lime dozers will cause short termed episodic spates in the limed rivers. The current situation has prompted a need for dose-response relationships based on short term exposures of Atlantic salmon to assess the potential population effects of episodic acidification. Water quality guidelines for salmon have been lacking, despite a large number of experiments, all demonstrating dose-response relationships between water chemistry and fish health. We have summarized results from 347 short-term (10 days) at an Al dose resulting in a gill Al concentration of up to 300 µg Alg-1 dw, a 3 day exposure resulting in a gill Al accumulation in the range of 25 to 60 µg Alg-1 dw reduces smolt to adult survival in a dose related manner by 20 to 50%. For smolt to adult survival, the biological significant response is delayed relative to the dose and occurs first after the fish enters the marine environment. In addition to exposure intensity and timing, exposure duration is important for the setting of critical limits.

  8. Evaluation of feed and feeding regime on growth performance, flesh quality and fecal viscosity of Atlantic salmon ( Salmo salar L.) in recirculating aquaculture systems

    Science.gov (United States)

    Sun, Guoxiang; Liu, Ying; Li, Yong; Li, Xian; Wang, Shunkui

    2015-10-01

    The effects of different feeds and feeding regimes on growth performance, flesh quality and fecal viscosity of Atlantic salmon ( Salmo salar L.) in recirculating aquaculture systems (RAS) were investigated. Fish (initial body weight of 1677 g ± 157 g) were fed with four commercial feeds (Nosan salmon-NS, Aller gold-AG, Skretting salmon-SS and Han ye-HY) in two feeding regimes (80% and 100% satiation) for 78 d. The results showed that salmon specific growth ratio (SGR) and weight gain ratio (WGR) were significantly affected by feed type and feeding regime ( P enzymes including protease, lipase and amylase were also significantly affected by feed type and feeding regime ( P pH among all groups showed significant differences ( P < 0.05), ranging from 26.67 to 29.67, while no obvious difference was found in flesh color. Fecal viscosity for different treatments showed no significant difference, though improvement was found in 100% satiation group. From present experiment, it was concluded that both feed type and feeding regime can affect the important quality attributes of Atlantic salmon.

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

    Science.gov (United States)

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

    2017-01-01

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

  10. Dévalaison et survie d'alevins de saumon atlantique (Salmo salar L. en milieu semi-naturel contrôlé

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    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. The effect of vaccination, ploidy and smolt production regime on pathological melanin depositions in muscle tissue of Atlantic salmon, Salmo salar L.

    Science.gov (United States)

    Larsen, H A S; Austbø, L; Nødtvedt, A; Fraser, T W K; Rimstad, E; Fjelldal, P G; Hansen, T; Koppang, E O

    2014-04-01

    The presence of melanin in muscle fillets of farmed salmon represents a considerable quality problem for the salmon industry with major economic concerns. In this study, we have examined the presence of abnormal pigmentation in vaccinated versus unvaccinated Atlantic salmon, Salmo salar L., and evaluated possible differences between diploid and triploid fish. Furthermore, the impact of the smolt production regime at ambient (4.5 °C) versus elevated temperature (16 °C) was investigated. Pigmented muscle spots were analysed for the expression of genes involved in melanization (tyrosinase gene family) and immune-related response in addition to morphological investigations. The proportion of fish with intramuscular melanin deposits was not significantly different between vaccinated and unvaccinated fish, regardless of ploidy. However, an interaction between vaccination and smolt regime was shown, where smoltification at elevated temperature after vaccination increased the number of affected individuals compared with vaccination followed by simulated natural smoltification. Furthermore, there were overall more fish with melanin spots amongst the triploids compared with their diploid counterparts. Transcription of the tyrosinase gene family confirmed an onsite melanogenesis in all pigment spots. The histological examination and the expression of the immune-related genes revealed a chronic polyphasic myopathy that was not affected by vaccination, ploidy or smolt production regime. © 2013 John Wiley & Sons Ltd.

  12. Food deprivation causes rapid changes in the abundance and glucidic composition of the cutaneous mucous cells of Atlantic salmon Salmo salar L.

    Science.gov (United States)

    Landeira-Dabarca, A; Álvarez, M; Molist, P

    2014-10-01

    Cutaneous mucus is the first physical and chemical barrier of fish. This slime layer is secreted by mucous cells located in the epidermis and is mainly composed of glycoproteins that have their origin in the diet. Therefore, food deprivation can potentially change the abundance and glucidic nature of skin mucous cells, thus changing the mucus properties. To test this hypothesis, we conducted an experiment with Atlantic salmon, Salmo salar L. Changes in the number and glucidic nature of epidermal mucus cells were analysed using standard techniques. The outcome of this study shows that food deprivation caused a rapid decrease in the density of epidermal mucous cells in Atlantic salmon. Lectin histochemistry revealed a change in the presence and stainability of some sugar residues in the mucous cells of unfed fish compared with fed fish. Given that the primary reason for mucus secretion in fish is for protection against infections, we speculate that the changes in the mucus properties caused by nutritional stress may affect their disease resistance. This fact is particularly important for fish that spend a period of time deprived of food, either as a part of their natural life cycle, or as part of farming practices. © 2013 John Wiley & Sons Ltd.

  13. Presence of Anisakis simplex (Rudolphi, 1809 det. Krabbe, 1878) and Hysterothylacium aduncum (Rudolphi, 1802) (Nematoda; Anisakidae) in runts of farmed Atlantic salmon, Salmo salar L.

    Science.gov (United States)

    Mo, T A; Gahr, A; Hansen, H; Hoel, E; Oaland, Ø; Poppe, T T

    2014-02-01

    One hundred farmed Atlantic salmon, Salmo salar L., were examined for the presence of nematodes by digestion of tissue in HCl-pepsin solution. All fish were sampled from one cage in a fish farm on the Norwegian south-west coast. Fifty harvest quality salmon, that is, salmon for human consumption (mean 5.4 kg, variation 3.0-7.6 kg), were sampled at the processing line while 50 salmon runts (mean 1.1 kg, variation 0.4-1.8 kg), discarded due to poor performance, were sampled from the discard bin after the grading station. Runts are individual fish with clear signs of poor performance over time and abnormal appearance and are thus not processed for human consumption. No nematodes were found in the musculature or viscera of the 50 harvest quality salmon. In total, 75 nematodes were found in 10 (20%) of the runts; 53 nematodes in the viscera and 22 in the musculature. Nematodes in the musculature were identified as Anisakis simplex (Rudolphi, 1809 det. Krabbe, 1878), while nematodes in the viscera were identified as A. simplex and Hysterothylacium aduncum (Rudolphi, 1802). © 2013 John Wiley & Sons Ltd.

  14. Bona fide evidence for natural vertical transmission of infectious salmon anemia virus in freshwater brood stocks of farmed Atlantic salmon (Salmo salar) in Southern Chile.

    Science.gov (United States)

    Marshall, Sergio H; Ramírez, Ramón; Labra, Alvaro; Carmona, Marisela; Muñoz, Cristián

    2014-06-01

    Infectious salmon anemia (ISA) is a severe disease that affects farmed Atlantic salmon (Salmo salar), causing outbreaks in seawater in most salmon-producing countries worldwide, with particular aggressiveness in southern Chile. The etiological agent of this disease is a virus belonging to the Orthomyxoviridae family, named infectious salmon anemia virus (ISAV). Although it has been suggested that this virus can be vertically transmitted, even in freshwater, there is a lack of compelling experimental evidence to confirm this. Here we demonstrate significant putative viral loads in the ovarian fluid as well as in the eggs of two brood stock female adult specimens that harbored the virus systemically but without clinical signs. The target virus corresponded to a highly polymorphic region 3 (HPR-3) variant, which is known to be virulent in seawater and responsible for recent and past outbreaks of this disease in Chile. Additionally, the virus recovered from the fluid as well as from the interior of the eggs was fully infective to a susceptible fish cell line. To our knowledge, this is the first robust evidence demonstrating mother-to-offspring vertical transmission of the infective virus on the one hand and the asymptomatic transmission of a virulent form of the virus in freshwater fish on the other hand. The robustness of the data presented here will contribute to a better understanding of the biology of the virus but most importantly will constitute a key management tool in the control of an aggressive agent constantly threatening the sustainability of the global salmon industry.

  15. The effects of dietary lipid and strain difference on polyunsaturated fatty acid composition and conversion in anadromous and landlocked salmon (Salmo salar L.) parr.

    Science.gov (United States)

    Rollin, Xavier; Peng, Jinglan; Pham, Diep; Ackman, Robert G; Larondelle, Yvan

    2003-02-01

    Five experimental diets containing different proportions of olive, sunflower and linseed oils were used in a 55-day feeding trial on both anadromous and landlocked parr of Atlantic salmon (Salmo salar) of the same age, in order to study the effects of diet and strain on growth and fatty acid composition and absolute gains in fish whole body triacylglycerols (TAG) and phospholipids (PL). Growth rate was higher in landlocked than in anadromous parr, but not between the different diets. By contrast, the effect of diet on whole body fatty acid composition was much more pronounced than that of strain difference. The fatty acids deposition results establish significant (Pbody TAG and PL of both stocks. They also indicate the selective deposition of 18:1n-9 compared with linoleic acid (LLA) and linolenic acid (LNA). Finally, the results suggest the occurrence of the conversion of LLA and LNA to long-chain polyunsaturated fatty acids, its stimulation by increased substrate availability, a significantly higher n-3 and n-6 polyunsaturated fatty acids conversion capacity in landlocked than in anadromous parr and a strong genetic influence on docosahexaenoic acid content in salmon parr PL.

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

    Science.gov (United States)

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

    2012-12-03

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

  17. 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.

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

    Science.gov (United States)

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

    2017-01-01

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

  19. The effects of ionic strength on the toxicity of aluminium to Atlantic salmon (Salmo salar under non-steady state chemical conditions

    Directory of Open Access Journals (Sweden)

    Antonio B.S. POLÉO

    2002-02-01

    Full Text Available We have tested the influence of water ionic strength on the toxicity of aluminium in fish by comparing the mortality of Atlantic salmon (Salmo salar parr exposed to Al-rich water with additions of Ca2+ or Na+. The fish were exposed in parallel to Al-rich water (Al 500 μg l-1, pH 5.8 under non-steady state conditions, with and without the addition of one of the two base cations. The amount of Na+ and Ca2+ added to the water was calculated in order to obtain an identical increase in water ionic strength. Fish mortality was dependent on water residence time and whether or not base cations were added to the Al-rich water. In all Al-exposures, the highest mortality was always observed in fish exposed to water with the shortest residence time. Mortality decreased systematically with increasing water residence time through the exposure set-up. The addition of a base cation, Ca2+ or Na+, to the Al-rich water reduced fish mortality significantly compared to the Al-only exposures. Furthermore, increasing ionic strength with Na+ reduced mortality to a larger extent than the corresponding increase in ionic strength by the addition of Ca2+. The variation in mortality between the various aluminium and base cation treatments is discussed in terms of aluminium chemistry, specific mitigating effects of Ca2+ and Na+, and the general importance of water ionic strength. This study clearly demonstrates that Ca2+ does not play an unique role as an ameliorating cation for Al-toxicity in fish under non-steady state chemical conditions. Thus, ionic strength seems to be important, probably for the interaction between aluminium and the gill surface, reducing the possibility for positively charged aluminium species to bind to negatively charged sites.

  20. 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 (nMSW = 205 vs. n1SW = 30; p sea age was more pronounced in females than in males in the rivers we studied. Logistic regression analysis of vgll3 SNP genotypes revealed increased probabilities of exhibiting higher sea age for 54Thr vgll3 and 323Lys vgll3 genotypes compared to alternative genotypes, depending on population and sex. Moreover, individuals carrying the heterozygous vgll3 SNP genotypes were more likely (>66%) to be female. In summary, two nonsynonymous vgll3 polymorphisms were confirmed in North American populations of Atlantic Salmon and our results suggest that variation at those loci correlates with sea age and sex. Our results also suggest that this correlation varies among populations. Future work would benefit from a more balanced sampling and from adding data on juvenile riverine life stages to contrast our data.

  1. 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.

  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. Consistent boldness behaviour in early emerging fry of domesticated Atlantic salmon (Salmo salar): Decoupling of behavioural and physiological traits of the proactive stress coping style.

    Science.gov (United States)

    Vaz-Serrano, J; Ruiz-Gomez, M L; Gjøen, H M; Skov, P V; Huntingford, F A; Overli, O; Höglund, E

    2011-06-01

    Individual variation in the way animals cope with stressors has been documented in a number of animal groups. In general, two distinct sets of behavioural and physiological responses to stress have been described: the proactive and the reactive coping styles. Some characteristics of stress coping style seem to be coupled to the time to emerge of fry from spawning redds in natural populations of salmonid fishes. In the present study, behavioural and physiological traits of stress coping styles were compared two and five months after emergence in farmed Atlantic salmon (Salmo salar), using individuals with an early or late time to emerge. Initially, compared to late emerging individuals, early emerging individuals showed a shorter time to resume feeding after transfer to rearing in isolation. Resumption of feeding after isolation was suggested to be related to boldness behaviour, rather than hunger, in the present study. This observation was repeated five months after emergence, demonstrating behavioural consistency over time in this trait. However, in other traits of proactive and reactive stress coping styles, such as social status, resting metabolism or post stress cortisol concentrations, early and late emerging individuals did not differ. Therefore, this study demonstrates that boldness in a novel environment is uncoupled from other traits of the proactive and reactive stress coping styles in farmed salmonids. It is possible that this decoupling is caused by the low competitive environment in which fish were reared. In natural populations of salmonids, however, the higher selection pressure at emergence could select for early emerging individuals with a proactive coping style. Copyright © 2011. Published by Elsevier Inc.

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

    Science.gov (United States)

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

    2018-01-01

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

  5. Nutrigenomic profiling of transcriptional processes affected in liver and distal intestine in response to a soybean meal-induced nutritional stress in Atlantic salmon (Salmo salar).

    Science.gov (United States)

    De Santis, Christian; Bartie, Kerry L; Olsen, Rolf E; Taggart, John B; Tocher, Douglas R

    2015-09-01

    The aim of the present study was to generate an experimental model to characterize the nutrigenomic profile of a plant-derived nutritional stress. Atlantic salmon (Salmo salar) was used as the model species. The nutritional stress was induced by inclusion of dietary defatted soybean meal (SBM), as this ingredient had been previously demonstrated to induce enteropathy in the distal intestine and reduce growth in salmon. Triplicate groups of Atlantic salmon were fed concentrations of 0, 100, 200 and 300 g kg(-1) SBM for 12 weeks and reduced growth performance was used as the indicator of nutritional stress. The transcriptome was analyzed in two tissues, liver and distal intestine, with the hypothesis being that the liver transcriptome would be characterized by gene expression responses related to overall growth and health performance, whereas intestinal gene expression would be dominated by specific responses to SBM. A set of 133 genes was differentially expressed in liver including 44 genes in common with the intestinal response. The liver-specific response included up-regulation of genes involved in protein digestion, energy metabolism and immune functions, whereas genes in other metabolic pathways were generally anabolic and down-regulated. These responses may be more related to general nutritional stress than to SBM per se. The transcriptomic profile in the distal intestine was consistent with the enteritis response as described previously. This study provides a comprehensive report on the profiles of liver and distal intestine transcriptomes, specifically highlighting the role of the liver in fish undergoing SBM-induced nutritional stress. Copyright © 2015 Elsevier Inc. All rights reserved.

  6. 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

  7. 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.

  8. Mineralization of the vertebral bodies in Atlantic salmon (Salmo salar L.) is initiated segmentally in the form of hydroxyapatite crystal accretions in the notochord sheath

    Science.gov (United States)

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

    2013-01-01

    We performed a sequential morphological and molecular biological study of the development of the vertebral bodies in Atlantic salmon (Salmo salar L.). Mineralization starts in separate bony elements which fuse to form complete segmental rings within the notochord sheath. The nucleation and growth of hydroxyapatite crystals in both the lamellar type II collagen matrix of the notochord sheath and the lamellar type I collagen matrix derived from the sclerotome, were highly similar. In both matrices the hydroxyapatite crystals nucleate and accrete on the surface of the collagen fibrils rather than inside the fibrils, a process that may be controlled by a template imposed by the collagen fibrils. Apatite crystal growth starts with the formation of small plate-like structures, about 5 nm thick, that gradually grow and aggregate to form extensive multi-branched crystal arborizations, resembling dendritic growth. The hydroxyapatite crystals are always oriented parallel to the long axis of the collagen fibrils, and the lamellar collagen matrices provide oriented support for crystal growth. We demonstrate here for the first time by means of synchroton radiation based on X-ray diffraction that the chordacentra contain hydroxyapatite. We employed quantitative real-time PCR to study the expression of key signalling molecule transcripts expressed in the cellular core of the notochord. The results indicate that the notochord not only produces and maintains the notochord sheath but also expresses factors known to regulate skeletogenesis: sonic hedgehog (shh), indian hedgehog homolog b (ihhb), parathyroid hormone 1 receptor (pth1r) and transforming growth factor beta 1 (tgfb1). In conclusion, our study provides evidence for the process of vertebral body development in teleost fishes, which is initially orchestrated by the notochord. PMID:23711083

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

    Science.gov (United States)

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

    2014-01-01

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

  10. Detection of vitellogenin and zona radiata protein expressions in surface mucus of immature juvenile Atlantic salmon (Salmo salar) exposed to waterborne nonylphenol

    Energy Technology Data Exchange (ETDEWEB)

    Meucci, Valentina [Department of Veterinary Clinics, Section of Pharmacology and Toxicology, University of Pisa, V. le delle Piagge 2, 56124 Pisa (Italy); Arukwe, Augustine [Department of Biology, Norwegian University of Science and Technology (NTNU), Hoyskoleringen 5, 7491 Trondheim (Norway)]. E-mail: arukwe@bio.ntnu.no

    2005-06-01

    Induction of blood plasma vitellogenin (Vtg) and zona radiata proteins (Zr-proteins) in male and juvenile of oviparous vertebrates was proposed and shown to be sensitive biomarkers for exposure to estrogen mimic. The time- and dose-dependent expression of Vtg and Zr-proteins in nonylphenol (NP) exposed juvenile Atlantic salmon (Salmo salar) is reported. Fish were exposed continuously to waterborne nonylphenol at 5, 15 and 50 {mu}g/L. Blood and surface mucus samples were collected after 3 and 7 days post-exposure. Nonylphenol-induced plasma and surface mucus levels of Vtg and Zr-protein were analysed using immunochemical methods (Western blot and enzyme-linked immunosorbent assay; ELISA). Both Vtg and Zr-protein levels in plasma and surface mucus showed similar and parallel nonylphenol-induced expression patterns after waterborne nonylphenol exposure and in a concentration- and time-dependent manner. Zr-proteins were significantly induced at the lowest concentration of nonylphenol after 3 and 7 days of exposure both in plasma and in surface mucus. We conclude that the detection of Vtg and Zr-proteins directly in the surface mucus of fish, and the correlation of these values with plasma protein biomarker values in xenoestrogen-treated fish represents a sensitive non-invasive system for the detection of these known endocrine disruptor biomarkers. The demonstration of detectable Vtg and Zr-protein levels from surface mucus is a potential biomarker for estrogenic compounds, and their presence should be considered as an improvement in the methods for detection of endocrine disrupting chemicals (EDCs) and related pollutants in the environment.

  11. 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.

  12. The kinetics of CD4+ and CD8+ T-cell gene expression correlate with protection in Atlantic salmon (Salmo salar L) vaccinated against infectious pancreatic necrosis.

    Science.gov (United States)

    Munang'andu, Hetron Mweemba; Fredriksen, Børge Nilsen; Mutoloki, Stephen; Dalmo, Roy Ambli; Evensen, Oystein

    2013-04-08

    Infectious pancreatic necrosis virus (IPNV) is a highly contagious disease causing high mortalities in juvenile salmonids. Lack of correlation between neutralizing antibodies and infecting virus suggests a likelihood of involvement of the cellular mediated immune response in vaccine protection. To elucidate the kinetics of CD4 and CD8 T-cells responses in vaccine protection, Atlantic salmon (Salmo salar L) were vaccinated with a high antigen (HiAg) or low antigen (LoAg) dose vaccine and challenged by cohabitation using a highly virulent Norwegian Sp strain. Analysis of T-cell gene expression in lymphoid organs (headkidney and spleen) showed that GATA-3 was positively correlated with increase in antibody levels when T-bet was low. Conversely, T-bet and FoxP3 were positively correlated with viral infection and negatively correlated with increase in antibody levels. Among the CD8+ T cell genes, expression of eomes and CD8α were positively correlated with increase in viral copy numbers and negatively correlated with increase in antibody levels. Up-regulation of granzyme A was highly correlated with increase in viral copy numbers in the LoAg and control groups indicating that this gene could save as a diagnostic marker of acute infection for IPNV during acute infection. In contrast, its down regulation in the HiAg which had low viral copy numbers corresponded with high antibody levels. Overall, these data show that the kinetics of CD4 and CD8 T-cell genes expression follow the same pattern as that observed in higher vertebrates. These findings suggest that functional signatures of the cellular mediated immune response could be evolutionary conserved across the vertebrate taxa and that they can effectively be used to monitor vaccine protection and infection progression of IPNV in Atlantic salmon. Copyright © 2013 Elsevier Ltd. All rights reserved.

  13. 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.

  14. Comparative study of pineal clock gene and AANAT2 expression in relation to melatonin synthesis in Atlantic salmon (Salmo salar) and European seabass (Dicentrarchus labrax).

    Science.gov (United States)

    McStay, Elsbeth; Migaud, Herve; Vera, Luisa Maria; Sánchez-Vázquez, Francisco Javier; Davie, Andrew

    2014-03-01

    The photoreceptive teleost pineal is considered to be essential to the generation, synchronisation and maintenance of biological rhythms, primarily via melatonin release. The role of internal (circadian clock) and external (light) signals controlling melatonin production in the fish pineal differs between species, yet the reasons underpinning this remain largely unknown. Whilst in salmonids, pineal melatonin is apparently regulated directly by light, in all other studied teleosts, rhythmic melatonin production persists endogenously under the regulation of clock gene expression. To better understand the role of clocks in teleost pineals, this study aimed to characterise the expression of selected clock genes in vitro under different photoperiodic conditions in comparison to in vivo in both Atlantic salmon (Salmo salar) and in European seabass (Dicentrarchus labrax) (in vitro 12L:12D), a species known to display endogenous rhythmic melatonin synthesis. Results revealed no rhythmic clock gene (Clock, Period 1 &2) expression in Atlantic salmon or European seabass (Clock and Period 1) pineal in vitro. However rhythmic expression of Cryptochrome 2 and Period 1 in the Atlantic salmon pineal was observed in vivo, which infers extra-pineal regulation of clocks in this species. No rhythmic arylalkylamine N-acetyltransferase 2 (Aanat2) expression was observed in the Atlantic salmon yet in the European seabass, circadian Aanat2 expression was observed. Subsequent in silico analysis of available Aanat2 genomic sequences reveals that Atlantic salmon Aanat2 promoter sequences do not contain similar regulatory architecture as present in European seabass, and previously described in other teleosts which alludes to a loss in functional connection in the pathway. Copyright © 2013 Elsevier Inc. All rights reserved.

  15. 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.

  16. Migratory patterns of hatchery and stream-reared Atlantic salmon Salmo salar smolts in the Connecticut River, U.S.A.

    Science.gov (United States)

    McCormick, S D; Haro, A; Lerner, D T; O'Dea, M F; Regish, A M

    2014-10-01

    The timing of downstream migration and detection rates of hatchery-reared Atlantic salmon Salmo salar smolts and stream-reared smolts (stocked 2 years earlier as fry) were examined in the Connecticut River (U.S.A.) using passive integrated transponder (PIT) tags implanted into fish and then detected at a downstream fish bypass collection facility at Turners Falls, MA (river length 192 km). In two successive years, hatchery-reared smolts were released in mid-April and early May at two sites: the West River (river length 241 km) or the Passumpsic (river length 450 km). Hatchery-reared smolts released higher in the catchment arrived 7 to 14 days later and had significantly lower detection rates than smolts stocked lower in the catchment. Hatchery-reared smolts released 3 weeks apart at the same location were detected downstream at similar times, indicating that early-release smolts had a lower average speed after release and longer residence time. The size and gill Na(+) /K(+) -ATPase (NKA) activity of smolts at the time of release were significantly greater for detected fish (those that survived and migrated) than for those that were not detected. Stream-reared pre-smolts (>11·5 cm) from four tributaries (length 261-551 km) were tagged in autumn and detected during smolt migration the following spring. Stream-reared smolts higher in the catchment arrived later and had significantly lower detection rates. The results indicate that both hatchery and stream-reared smolts from the upper catchment will arrive at the mouth of the river later and experience higher overall mortality than fish from lower reaches, and that both size and gill NKA activity are related to survival during downstream migration. © 2014 The Fisheries Society of the British Isles.

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

    Science.gov (United States)

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

    2016-02-01

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

  18. Influence of stocking density on growth, body composition and energy budget of Atlantic salmon Salmo salar L. in recirculating aquaculture systems

    Science.gov (United States)

    Liu, Baoliang; Liu, Ying; Liu, Ziyi; Qiu, Denggao; Sun, Guoxiang; Li, Xian

    2014-09-01

    Atlantic salmon Salmo salar were reared at four stocking densities—high density D 1 (final density ˜39 kg/m3), medium densities D 2 (˜29 kg/m3) and D 3 (˜19 kg/m3), and low density D 4 (˜12 kg/m3)—for 40 days to investigate the effect of stocking density on their growth performance, body composition and energy budgets. Stocking density did not significantly affect specific growth rate in terms of weight (SGRw) but did affect specific growth rate in terms of energy (SGRe). Stocking density significantly influenced the ration level (RLw and RLe), feed conversion ratio (FCRw and FCRe) and apparent digestibility rate (ADR). Ration level and FCRw tended to increase with increasing density. Fish at the highest density D 1 and lowest density D 4 showed lower FCRe and higher ADR than at medium densities. Stocking density significantly affected protein and energy contents of the body but did not affect its moisture, lipid, or ash contents. The expenditure of energy for metabolism in the low-density and high-density groups was lower than that in the medium-density groups. Stocking density affected energy utilization from the feces but had no effect on excretion rate. The greater energy allocation to growth at high density and low density may be attributed to reduced metabolic rate and increased apparent digestibility rate. These findings provide information that will assist selection of suitable stocking densities in the Atlantic-salmon-farming industry.

  19. Atlantic salmon (Salmo salar) muscle precursor cells differentiate into osteoblasts in vitro: polyunsaturated fatty acids and hyperthermia influence gene expression and differentiation.

    Science.gov (United States)

    Ytteborg, Elisabeth; Vegusdal, Anne; Witten, P Eckhard; Berge, Gerd Marit; Takle, Harald; Østbye, Tone-Kari; Ruyter, Bente

    2010-02-01

    The formation and mineralisation of bone are two critical processes in fast-growing Atlantic salmon (Salmo salar). The mechanisms of these processes, however, have not been described in detail. Thus, in vitro systems that allow the study of factors that influence bone formation in farmed Atlantic salmon are highly warranted. We describe here a method by which unspecialized primary cells from salmon white muscle can differentiate to osteoblasts in vitro. We have subsequently used the differentiated cells as a model system to study the effects of two factors that influence bone formation in Atlantic salmon under commercial farming conditions, namely polyunsaturated fatty acids, PUFAs, and temperature. Muscle precursor cells changed their morphology from triangular or spindle-shaped cells to polygonal or cubical cells after 3 weeks in osteogenic medium. In addition, gene expression studies showed that marker genes for osteoblastogenesis; alp, col1a1, osteocalcin, bmp2 and bmp4 increased after 3 weeks of incubation in osteogenic media showing that these cells have differentiated to osteoblasts at this stage. Adding CLA or DHA to the osteoblast media resulted in a reduced PGE(2) production and increased expression of osteocalcin. Further, temperature studies showed that differentiating osteoblasts are highly sensitive to increased incubation temperature at early stages of differentiation. Our studies show that unspecialized precursor cells isolated from salmon muscle tissue can be caused to differentiate to osteoblasts in vitro. Furthermore, this model system appears to be suitable for the study of osteoblast biology in vitro. 2009 Elsevier B.V. All rights reserved.

  20. Enhanced transcriptomic responses in the Pacific salmon louse Lepeophtheirus salmonis oncorhynchi to the non-native Atlantic Salmon Salmo salar suggests increased parasite fitness.

    Science.gov (United States)

    Braden, Laura M; Sutherland, Ben J G; Koop, Ben F; Jones, Simon R M

    2017-01-30

    Outcomes of infections with the salmon louse Lepeophtheirus salmonis vary considerably among its natural hosts (Salmo, Oncorhynchus spp.). Host-parasite interactions range from weak to strong host responses accompanied by high to low parasite abundances, respectively. Parasite behavioral studies indicate that the louse prefers the host Atlantic Salmon (Salmo salar), which is characterized by a weak immune response, and that this results in enhanced parasite reproduction and growth rates. Furthermore, parasite-derived immunosuppressive molecules (e.g., proteases) have been detected at higher amounts in response to the mucus of Atlantic Salmon relative to Coho Salmon (Oncorhynchus kisutch). However, the host-specific responses of the salmon louse have not been well characterized in either of the genetically distinct sub-species that occur in the Atlantic and Pacific Oceans. We assessed and compared the transcriptomic feeding response of the Pacific salmon louse (L. salmonis oncorhynchi,) while parasitizing the highly susceptible Atlantic Salmon and Sockeye Salmon (Oncorhynchus nerka) or the more resistant Coho Salmon (Oncorhynchus kisutch) using a 38 K oligonucleotide microarray. The response of the louse was enhanced both in the number of overexpressed genes and in the magnitude of expression while feeding on the non-native Atlantic Salmon, compared to either Coho or Sockeye Salmon. For example, putative virulence factors (e.g., cathepsin L, trypsin, carboxypeptidase B), metabolic enzymes (e.g., cytochrome B, cytochrome C), protein synthesis enzymes (e.g., ribosomal protein P2, 60S ribosomal protein L7), and reproduction-related genes (e.g., estrogen sulfotransferase) were overexpressed in Atlantic-fed lice, indicating heightened parasite fitness with this host species. In contrast, responses in Coho- or Sockeye-fed lice were more similar to those of parasites deprived of a host. To test for host acclimation by the parasite, we performed a reciprocal host transfer

  1. The dietary replacement of marine ingredients by terrestrial animal and plant alternatives modulates the antiviral immune response of Atlantic salmon (Salmo salar).

    Science.gov (United States)

    Caballero-Solares, Albert; Hall, Jennifer R; Xue, Xi; Eslamloo, Khalil; Taylor, Richard G; Parrish, Christopher C; Rise, Matthew L

    2017-05-01

    The effects of replacing marine ingredients by terrestrial ingredients on the health of Atlantic salmon (Salmo salar) are poorly understood. During a 14-week trial, Atlantic salmon fed a fish meal-fish oil based diet (MAR) showed similar growth performance to others fed a plant protein/vegetable oil based diet (VEG), whereas poorer performance was observed in those fed an animal by-product meal/vegetable oil based diet (ABP). At the end of the trial, salmon were injected with either phosphate-buffered saline (PBS) or the viral mimic polyriboinosinic polyribocytidylic acid (pIC) and sampled for head kidney RNA after 24 h. The levels of 27 immune-related transcripts, and of 5 others involved in eicosanoid synthesis (including paralogues in both cases) were measured in the head kidney of the salmon using qPCR. All of the assayed immune-related genes and cox2 were pIC-induced, while the other eicosanoid synthesis-related genes were pIC-repressed. Linear regression was used to establish correlations between different immune transcripts, elucidating the cascade of responses to pIC and specialization among paralogues. Regarding the effect of diet on the antiviral immune response, pIC-treated fish fed diets ABP and VEG showed higher transcript levels of tlr3, irf1b, stat1a, isg15b, and gig1 compared to those fed diet MAR. We infer that the observed dietary immunomodulation could be due to the lower proportion of arachidonic acid (ARA), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA) in diets ABP and VEG. Furthermore, our results suggest a major role of dietary ARA in Atlantic salmon immunity, as low ARA proportion in diet VEG coincided with the highest pIC-induction of some immune transcripts (tlr7, stat1c, mxb, and gig1) and the lowest levels of transcripts encoding eicosanoid-synthesizing enzymes (5loxa, 5loxb, and pgds). In contrast, the high ARA/EPA ratio of diet ABP appeared to favor increased expression of transcripts involved in the synthesis of pro

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

    Science.gov (United States)

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

    2013-12-01

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

  3. 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

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

    Science.gov (United States)

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

    2008-01-01

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

  5. Assessment of Heavy Metals (Cadmium and Lead in Vacuum Packaged Smoked Fish Species (Mackerel, Salmo salar and Oncorhynhus mykiss Marketed in Ankara (Turkey.

    Directory of Open Access Journals (Sweden)

    U. Tansel Şireli

    2015-12-01

    Full Text Available Ankara’daki marketlerde vakum paketli dumanlanmış balık türlerinde (Mackerel, Salmo salar ve Oncorhynhus mykiss ağır metallerin (kadmiyum ve kurşun belirlenmesi. Ankara’daki marketlerde, ticari olarak satılan dumanlanmış ve vakum paketlenmiş balık türlerindeki kadmiyum (Cd ve kurşun (Pb konsantrasyonları değerlendirilmiştir. 2004-2005 yılları arasında Ankara’daki hipermarketlerden toplam 73 adet dumanlanıp paketlenmiş balık fileto örneği temin edilmiştir. İz element konsantrasyonu GFAAS yöntemi ile ölçülmüştür. Cd için sınır değer kuru maddede 0.003-0.034 mg kg -1 olarak bulunurken, Pb için bu değer 0.001-0.791 mg kg-1 olarak bulunmuştur. Analiz edilen tüm balık örneklerinde kadmiyum konsantrasyonu, Türkiye ve Avrupa Birliği Mevzuatı tarafından 0.05 mg kg-1 olarak belirlenen limitlerin altındayken, 27 balık örneğindeki Pb seviyesi Türkiye’deki kabul edilebilir limitleri aşmıştır (0.2 mg kg-1. Buna rağmen, yüksek seviyelerde ölçülen ağır metal konsantrasyonlarında bile, haftada 400 g balık tüketen 60 kg ağırlığında bir yetişkinin tahmini haftalık Pb ve Cd alım miktarı, Joint FAO/WHO Expert Committee tarafından tavsiye edilen geçici tolere edilebilir haftalık alım miktarının (Cd için 7 µg-kg-1 ve Pb için 25 µg kg-1 altında olduğu saptanmıştır

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

    Science.gov (United States)

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

    2008-08-04

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

  7. 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

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    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

  8. 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.

  9. Single nucleotide polymorphism (SNP discovery in duplicated genomes: intron-primed exon-crossing (IPEC as a strategy for avoiding amplification of duplicated loci in Atlantic salmon (Salmo salar and other salmonid fishes

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    Primmer Craig R

    2006-07-01

    Full Text Available Abstract Background Single nucleotide polymorphisms (SNPs represent the most abundant type of DNA variation in the vertebrate genome, and their applications as genetic markers in numerous studies of molecular ecology and conservation of natural populations are emerging. Recent large-scale sequencing projects in several fish species have provided a vast amount of data in public databases, which can be utilized in novel SNP discovery in salmonids. However, the suggested duplicated nature of the salmonid genome may hamper SNP characterization if the primers designed in conserved gene regions amplify multiple loci. Results Here we introduce a new intron-primed exon-crossing (IPEC method in an attempt to overcome this duplication problem, and also evaluate different priming methods for SNP discovery in Atlantic salmon (Salmo salar and other salmonids. A total of 69 loci with differing priming strategies were screened in S. salar, and 27 of these produced ~13 kb of high-quality sequence data consisting of 19 SNPs or indels (one per 680 bp. The SNP frequency and the overall nucleotide diversity (3.99 × 10-4 in S. salar was lower than reported in a majority of other organisms, which may suggest a relative young population history for Atlantic salmon. A subset of primers used in cross-species analyses revealed considerable variation in the SNP frequencies and nucleotide diversities in other salmonids. Conclusion Sequencing success was significantly higher with the new IPEC primers; thus the total number of loci to screen in order to identify one potential polymorphic site was six times less with this new strategy. Given that duplication may hamper SNP discovery in some species, the IPEC method reported here is an alternative way of identifying novel polymorphisms in such cases.

  10. Water quality limits for Atlantic salmon (Salmo salar L. exposed to short term reductions in pH and increased aluminum simulating episodes

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    T. Kristensen

    2008-03-01

    Full Text Available Acidification has caused the loss or reduction of numerous Atlantic salmon (Salmo salar L. populations on both sides of the North Atlantic. Acid deposition peaked in the 1980's and resulted in both chronically and episodically acidified rivers. At present, water quality is improving in all affected rivers due to reduced acid deposition. However, spring snow melt, heavy rainfall and sea salt episodes can still cause short term drops in pH and elevated concentrations of bioavailable aluminum. Technical malfunction in lime dozers will cause short termed episodic spates in the limed rivers. The current situation has prompted a need for dose-response relationships based on short term exposures of Atlantic salmon to assess the potential population effects of episodic acidification. Water quality guidelines for salmon have been lacking, despite a large number of experiments, all demonstrating dose-response relationships between water chemistry and fish health. We have summarized results from 347 short-term (<14 days exposures of salmon parr and smolt performed between 1990 and 2003 in Norway. The experiments have been performed as bioassays, where fish have been exposed in tanks fed river water, in tanks where the river water quality has been manipulated (added H+ and Al and as Carlin-tagged smolt releases after preexposure to moderately acidic waters. The results from the various bioassays are compared to water quality limits proposed on basis of the relationship between water quality and population status/health in Norwegian rivers. The focus of this article is placed on chemical-biological interactions that can be drawn across experiments and exposure protocols. We propose dose-response relationships for acid neutralizing capacity (ANC, pH, cationic Al and gill accumulated Al, versus mortality in freshwater, effects on hypo-osmoregulatory capacity in seawater challenge tests and on smolt to adult survival in release experiments. The "no effect" dose

  11. Effects of production intensity and production strategies in commercial Atlantic salmon smolt (Salmo salar L.) production on subsequent performance in the early sea stage.

    Science.gov (United States)

    Kristensen, T; Haugen, T O; Rosten, T; Fjellheim, A; Atland, A; Rosseland, B O

    2012-02-01

    A data set from commercial Atlantic salmon (Salmo salar L.) producers on production intensity and production strategies in smolt tanks (N = 63-94) was obtained during 1999-2006. The effects of production intensity on subsequent fish mortality and growth during the early sea phase (90 days) were examined by principal component analysis and subsequent generalized linear model analysis. Levels of accumulated metabolites (CO(2), total ammonia nitrogen and NH(3)), and information provided by producers (production density (kg fish m(3-1)), specific water use (l kg fish(-1) min(-1)) and oxygen drop (mg l(-1)) from tank inlet to tank outlet), were used as predictor variables. In addition, several other welfare relevant variables such as disease history, temperature during freshwater and sea stage; season (S1) or off-season (S0) smolt production; and the use of seawater addition during the freshwater stage were analyzed. No strong intensity effects on mortality or growth were found. CO(2) levels alone (P water use (R(2) = 0.20), had the strongest effect on mortality. In both cases, mortality decreased with increasing density. For growth, the intensity model with the most support (R(2) = 0.17) was O(2) drop, density and their interaction effects, resulting in the best growth at low and high intensity, and poorer growth at intermediate levels. Documented viral disease outbreaks (infectious pancreatic necrosis and two cases of pancreas disease) in the sea phase resulted in significantly higher mortalities at 90 days compared with undiagnosed smolt groups, although mortalities were highly variable in both categories. The temperature difference between the freshwater stage and seawater had a small, but significant, effect on growth with the best growth in groups stocked to warmer seawater (P = 0.04, R(2) = 0.06). S0 and S1 smolt groups did not differ significantly in growth, but the mortality was significantly (P = 0.02) higher in S1 groups. Seawater addition as a categorical

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

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    Moen Thomas

    2009-08-01

    Full Text Available Abstract Background Infectious pancreatic necrosis (IPN is one of the most prevalent and economically devastating diseases in Atlantic salmon (Salmo salar farming worldwide. The disease causes large mortalities at both the fry- and post-smolt stages. Family selection for increased IPN resistance is performed through the use of controlled challenge tests, where survival rates of sib-groups are recorded. However, since challenge-tested animals cannot be used as breeding candidates, within-family selection is not performed and only half of the genetic variation for IPN resistance is being exploited. DNA markers linked to quantitative trait loci (QTL affecting IPN resistance would therefore be a powerful selection tool. The aim of this study was to identify and fine-map QTL for IPN-resistance in Atlantic salmon, for use in marker-assisted selection to increase the rate of genetic improvement for this trait. Results A genome scan was carried out using 10 large full-sib families of challenge-tested Atlantic salmon post-smolts and microsatellite markers distributed across the genome. One major QTL for IPN-resistance was detected, explaining 29% and 83% of the phenotypic and genetic variances, respectively. This QTL mapped to the same location as a QTL recently detected in a Scottish Atlantic salmon population. The QTL was found to be segregating in 10 out of 20 mapping parents, and subsequent fine-mapping with additional markers narrowed the QTL peak to a 4 cM region on linkage group 21. Challenge-tested fry were used to show that the QTL had the same effect on fry as on post-smolt, with the confidence interval for QTL position in fry overlapping the confidence interval found in post-smolts. A total of 178 parents were tested for segregation of the QTL, identifying 72 QTL-heterozygous parents. Genotypes at QTL-heterozygous parents were used to determine linkage phases between alleles at the underlying DNA polymorphism and alleles at single markers or

  13. 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

  14. 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; 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

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

    Science.gov (United States)

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

    2009-01-01

    Background Infectious pancreatic necrosis (IPN) is one of the most prevalent and economically devastating diseases in Atlantic salmon (Salmo salar) farming worldwide. The disease causes large mortalities at both the fry- and post-smolt stages. Family selection for increased IPN resistance is performed through the use of controlled challenge tests, where survival rates of sib-groups are recorded. However, since challenge-tested animals cannot be used as breeding candidates, within-family selection is not performed and only half of the genetic variation for IPN resistance is being exploited. DNA markers linked to quantitative trait loci (QTL) affecting IPN resistance would therefore be a powerful selection tool. The aim of this study was to identify and fine-map QTL for IPN-resistance in Atlantic salmon, for use in marker-assisted selection to increase the rate of genetic improvement for this trait. Results A genome scan was carried out using 10 large full-sib families of challenge-tested Atlantic salmon post-smolts and microsatellite markers distributed across the genome. One major QTL for IPN-resistance was detected, explaining 29% and 83% of the phenotypic and genetic variances, respectively. This QTL mapped to the same location as a QTL recently detected in a Scottish Atlantic salmon population. The QTL was found to be segregating in 10 out of 20 mapping parents, and subsequent fine-mapping with additional markers narrowed the QTL peak to a 4 cM region on linkage group 21. Challenge-tested fry were used to show that the QTL had the same effect on fry as on post-smolt, with the confidence interval for QTL position in fry overlapping the confidence interval found in post-smolts. A total of 178 parents were tested for segregation of the QTL, identifying 72 QTL-heterozygous parents. Genotypes at QTL-heterozygous parents were used to determine linkage phases between alleles at the underlying DNA polymorphism and alleles at single markers or multi-marker haplotypes

  16. 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

  17. 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.

    Science.gov (United States)

    Betancor, Mónica B; Li, Keshuai; Sprague, Matthew; Bardal, Tora; Sayanova, Olga; Usher, Sarah; Han, Lihua; Måsøval, Kjell; Torrissen, Ole; Napier, Johnathan A; Tocher, Douglas R; Olsen, Rolf Erik

    2017-01-01

    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.

  18. 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.

  19. mRNA expression of antioxidant enzymes (SOD, CAT and GSH-Px) and lipid peroxidative stress in liver of Atlantic salmon (Salmo salar) exposed to hyperoxic water during smoltification.

    Science.gov (United States)

    Olsvik, P A; Kristensen, T; Waagbø, R; Rosseland, B O; Tollefsen, K-E; Baeverfjord, G; Berntssen, M H G

    2005-07-01

    The mRNA levels of three antioxidant genes, Cu/Zn superoxide dismutase (SOD), catalase (CAT) and phospholipid hydroperoxide glutathione peroxidase (GSH-Px), were quantified with real-time qRT-PCR in liver of Atlantic salmon Salmo salar exposed to 80% (normoxia), 105% and 130% O2 saturation for 54 days. The salmon were then translocated and exposed to 90% and 130% O2 saturation for additional 72 days during smoltification. TBARS and vitamin E levels in liver and the levels of oxidized glutathione (GSSG), total glutathione (GSH) and the resulting oxidative stress index (OSI) in blood were quantified as traditional oxidative stress markers. No significant mean normalized expression (MNE) differences of SOD, CAT or GSH-Px were found in liver after hyperoxia exposure at the two sampling times. Significantly decreased OSI was found in smolt exposed to 130% O2 saturation after 126 days (n = 18, P < 0.0001), indicating hyperoxia-induced oxidative stress. No effects were seen on growth, or on the levels of thiobarbituric reactive substances (TBARS) and vitamin E in liver after the exposure experiment. Overall, the mRNA expression of SOD, CAT and GSH-Px in liver related poorly with the hyperoxic exposure regimes, and more knowledge are needed before the expressed levels of these antioxidant genes can be applied as biomarkers of hyperoxia in Atlantic salmon.

  20. 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 (Ir), 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 Ir, higher DL and collagenase activity, and on average, paler and less yellowish fillets. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. 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.

  2. A survey of wild marine fish identifies a potential origin of an outbreak of viral haemorrhagic septicaemia in wrasse, Labridae, used as cleaner fish on marine Atlantic salmon, Salmo salar L., farms.

    Science.gov (United States)

    Wallace, I S; Donald, K; Munro, L A; Murray, W; Pert, C C; Stagg, H; Hall, M; Bain, N

    2015-06-01

    Viral haemorrhagic septicaemia virus (VHSV) was isolated from five species of wrasse (Labridae) used as biological controls for parasitic sea lice predominantly, Lepeophtheirus salmonis (Krøyer, 1837), on marine Atlantic salmon, Salmo salar L., farms in Shetland. As part of the epidemiological investigation, 1400 wild marine fish were caught and screened in pools of 10 for VHSV using virus isolation. Eleven pools (8%) were confirmed VHSV positive from: grey gurnard, Eutrigla gurnardus L.; Atlantic herring, Clupea harengus L.; Norway pout, Trisopterus esmarkii (Nilsson); plaice, Pleuronectes platessa L.; sprat, Sprattus sprattus L. and whiting, Merlangius merlangus L. The isolation of VHSV from grey gurnard is the first documented report in this species. Nucleic acid sequencing of the partial nucleocapsid (N) and glycoprotein (G) genes was carried out for viral characterization. Sequence analysis confirmed that all wild isolates were genotype III the same as the wrasse and there was a close genetic similarity between the isolates from wild fish and wrasse on the farms. Infection from these local wild marine fish is the most likely source of VHSV isolated from wrasse on the fish farms. © 2014 Crown Copyright. Journal of Fish Diseases © 2014 John Wiley & Sons Ltd.

  3. 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

    Energy Technology Data Exchange (ETDEWEB)

    Croce, B. [Scottish Office Agriculture, Environment, and Fisheries Dept., Aberdeen (United Kingdom). Marine Lab.]|[Scottish Environmental Protection Agency, Aberdeen (United Kingdom). North East River Purification Board; Stagg, R.M. [Scottish Office Agriculture, Environment, and Fisheries Dept., Aberdeen (United Kingdom). Marine Lab.

    1997-09-01

    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 {micro}g/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 {micro}g/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.

  4. Concurrent injection of a rhabdovirus-specific DNA vaccine with a polyvalent, oil-adjuvanted vaccine delays the specific anti-viral immune response in Atlantic salmon, Salmo salar L.

    Science.gov (United States)

    Skinner, Lisa A; LaPatra, S E; Adams, A; Thompson, K D; Balfry, S K; McKinley, R S; Schulte, P M

    2010-04-01

    Vaccines are commonly used in salmonid aquaculture as a method of disease prevention. Although there is a substantial amount of published research regarding the immunological and physiological effects following the injection of different polyvalent vaccines and DNA vaccines, there are no published reports examining the physiological and immunological effects of concurrent vaccine injection, which is the situation encountered in aquaculture. Using key immunological parameters such as lysozyme activity and specific antibody titres we examined the short-term activation of the immune response of cultured Atlantic salmon (Salmo salar L.) following concurrent injection with a traditional, polyvalent, oil-adjuvanted vaccine (AV) and an IHNV-specific DNA vaccine (DV). Our results indicate that different aspects of the innate and adaptive immune responses are influenced in either a positive or negative manner. While concurrent vaccine injection elicited an increase in lysozyme activity, changes in antibody titre (Ab) were antigen specific. The production of anti-Aeromonas salmonicida Abs was significantly greater in the combined vaccine group at 296 degree days post-vaccine injection (dd pvi), while the production of anti-Listonella anguillarum Abs was significantly greater at 106 dd pvi in the combined vaccine group. Of even greater interest was the apparent delay in production of IHNV-specific neutralizing antibodies (NAb) when the DV was injected concurrently with the polyvalent AV. The results indicated that concurrent injection of a polyvalent oil-AV and a DV can be beneficial to the production of antibodies; however, the specific anti-viral response may be delayed. Copyright 2010 Elsevier Ltd. All rights reserved.

  5. Requirements of n-3 very long-chain PUFA in Atlantic salmon (Salmo salar L): effects of different dietary levels of EPA and DHA on fish performance and tissue composition and integrity.

    Science.gov (United States)

    Bou, Marta; Berge, Gerd M; Baeverfjord, Grete; Sigholt, Trygve; Østbye, Tone-Kari; Romarheim, Odd Helge; Hatlen, Bjarne; Leeuwis, Robin; Venegas, Claudia; Ruyter, Bente

    2017-01-01

    Farmed salmon feeds have changed from purely marine-based diets with high levels of EPA and DHA in the 1990s to the current 70 % plant-based diets with low levels of these fatty acids (FA). The aim of this study was to establish the impacts of low dietary EPA and DHA levels on performance and tissue integrity of Atlantic salmon (Salmo salar). Atlantic salmon (50 g) in seawater were fed fourteen experimental diets, containing five levels (0, 0·5, 1·0, 1·5 and 2·0 %) of EPA, DHA or a 1:1 EPA+DHA plus control close to a commercial diet, to a final weight of 400 g. Lack of EPA and DHA did not influence mortality, but the n-3-deficient group exhibited moderately slower growth than those fed levels above 0·5 %. The heart and brain conserved EPA and DHA levels better than skeletal muscle, liver, skin and intestine. Decreased EPA and DHA favoured deposition of pro-inflammatory 20 : 4n-6 and 20 : 3n-6 FA in membrane phospholipids in all tissues. When DHA was excluded from diets, 18 : 3n-3 and EPA were to a large extent converted to DHA. Liver, skeletal and cardiac muscle morphology was normal in all groups, with the exception of cytoplasm packed with large or foamy vacuoles and sometimes swollen enterocytes of intestine in both deficient and EPA groups. DHA supplementation supported normal intestinal structure, and 2·0 % EPA+DHA alleviated deficiency symptoms. Thus, EPA and DHA dietary requirements cannot be based exclusively on growth; tissue integrity and fish health also need to be considered.

  6. Influencia del α-tocoferol en la incorporación y peroxidación del ácido araquidónico en alevines parr de salmón del Atlántico (Salmo salar L.

    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 < 0,05 entre los tratamientos. La relación sinérgica entre el ARA/a-tocoferol mostró influencia (P < 0,05 solamente en el hígado, observándose que un alto nivel de α-tocoferol y ARA favoreció la acumulación de ácidos grasos en este tejido. Los niveles de α-tocoferol encontrados en los tejidos mostraron relación directamente proporcional a su incorporación en la dieta. Sin embargo, una concentración de hasta 0,6% de ARA en la dieta no requiere incrementar el nivel de α-tocoferol. Los datos obtenidos en este estudio demostraron que la interacción entre el ARA y el α-tocoferol influyeron en forma sinérgica sobre la acumulación de los ácidos grasos en el hígado.

  7. 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.

  8. Effects of environmental stress on mRNA expression levels of seven genes related to oxidative stress and growth in Atlantic salmon Salmo salar L. of farmed, hybrid and wild origin

    Science.gov (United States)

    2012-01-01

    Background Ten generations of domestication selection has caused farmed Atlantic salmon Salmo salar L. to deviate from wild salmon in a range of traits. Each year hundreds of thousands of farmed salmon escape into the wild. Thus, interbreeding between farmed escapees and wild conspecifics represents a significant threat to the genetic integrity of wild salmon populations. In a previous study we demonstrated how domestication has inadvertently selected for reduced responsiveness to stress in farmed salmon. To complement that study, we have evaluated the expression of seven stress-related genes in head kidney of salmon of farmed, hybrid and wild origin exposed to environmentally induced stress. Results In general, the crowding stressor used to induce environmental stress did not have a strong impact on mRNA expression levels of the seven genes, except for insulin-like growth factor-1 (IGF-1) that was downregulated in the stress treatment relative to the control treatment. mRNA expression levels of glutathione reductase (GR), Cu/Zn superoxide dismutase (Cu/Zn SOD), Mn superoxide dismutase (Mn SOD), glutathione peroxidase (GP) and IGF-1 were affected by genetic origin, thus expressed significantly different between the salmon of farmed, hybrid or wild origin. A positive relationship was detected between body size of wild salmon and mRNA expression level of the IGF-1 gene, in both environments. No such relationship was observed for the hybrid or farmed salmon. Conclusion Farmed salmon in this study displayed significantly elevated mRNA levels of the IGF-1 gene relative to the wild salmon, in both treatments, while hybrids displayed a non additive pattern of inheritance. As IGF-1 mRNA levels are positively correlated to growth rate, the observed positive relationship between body size and IGF-1 mRNA levels detected in the wild but neither in the farmed nor the hybrid salmon, could indicate that growth selection has increased IGF-1 levels in farmed salmon to the extent

  9. Modelling growth performance and feeding behaviour of Atlantic salmon (Salmo salar L.) in commercial-size aquaculture net pens: Model details and validation through full-scale experiments.

    Science.gov (United States)

    Føre, Martin; Alver, Morten; Alfredsen, Jo Arve; Marafioti, Giancarlo; Senneset, Gunnar; Birkevold, Jens; Willumsen, Finn Victor; Lange, Guttorm; Espmark, Åsa; Terjesen, Bendik Fyhn

    2016-11-01

    We have developed a mathematical model which estimates the growth performance of Atlantic salmon in aquaculture production units. The model consists of sub-models estimating the behaviour and energetics of the fish, the distribution of feed pellets, and the abiotic conditions in the water column. A field experiment where three full-scale cages stocked with 120,000 salmon each (initial mean weight 72.1  ± SD 2.8 g) were monitored over six months was used to validate the model. The model was set up to simulate fish growth for all the three cages using the feeding regimes and observed environmental data as input, and simulation results were compared with the experimental data. Experimental fish achieved end weights of 878, 849 and 739 g in the three cages respectively. However, the fish contracted Pancreas Disease (PD) midway through the experiment, a factor which is expected to impair growth and increase mortality rate. The model was found able to predict growth rates for the initial period when the fish appeared to be healthy. Since the effects of PD on fish performance are not modelled, growth rates were overestimated during the most severe disease period. This work illustrates how models can be powerful tools for predicting the performance of salmon in commercial production, and also imply their potential for predicting differences between commercial scale and smaller experimental scales. Furthermore, such models could be tools for early detection of disease outbreaks, as seen in the deviations between model and observations caused by the PD outbreak. A model could potentially also give indications on how the growth performance of the fish will suffer during such outbreaks. We believe that our manuscript is relevant for the aquaculture industry as it examines the growth performance of salmon in a fish farm in detail at a scale, both in terms of number of fish and in terms of duration, that is higher than usual for such studies. In addition, the fish

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

    DEFF Research Database (Denmark)

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

    2008-01-01

    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...... several candidate genes associated with preparatory adaptations to different life histories in salmonids, including genes encoding for transaldolase 1, constitutive heat-shock protein HSC70-1 and endozepine. Some of these genes clustered into functional groups, providing insight into the physiological...... 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...

  11. 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 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.

  12. 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).

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

    Science.gov (United States)

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

    2011-11-01

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

  14. Flow preferences of upstream migrating Atlantic salmon (Salmo salar)

    OpenAIRE

    Lindberg, Dan-Erik

    2016-01-01

    On their way from the sea to their spawning grounds in rivers, Atlantic salmon are often delayed or hindered by dams or other obstructions. Building a fishway can save a population that would otherwise go extinct. But even when there is a fishway present, sometimes the fish will have difficulties finding the entrance or navigating through the fishway. Understanding fish preferences during their upstream migration can help us improve fishway design so we can help the fish move upstream. T...

  15. 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.

  16. "NOME" NOS SALMOS

    Directory of Open Access Journals (Sweden)

    Luis Stadelmann

    1997-01-01

    Full Text Available "Nome" ocorre 96 vezes nos Salmos de maneira diferente do uso comum que dele se faz na nossa linguagem. O motivo é que "nome" é um termo referencial que designa a Deus cultuado na liturgia da comunidade dos fiéis. Distinguimos duas modalidades no uso de "nome": a primeira consiste na invocação do "nome" em súplicas pela intervenção de Deus, para que venha em auxílio dos homens por meio do seu poder irresistível, de sua autoridade suprema e de sua soberania ilimitada; a segunda se emprega nos encâmios ao "nome" para enaltecer a glória, honra e santidade de Deus.

  17. 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...

  18. Muscle Protein Profiles Used for Prediction of Texture of Farmed Salmon (Salmo salar L.)

    DEFF Research Database (Denmark)

    Johansson, Gine Ørnholt; Frosch, Stina; Gudjónsdóttir, María

    2017-01-01

    industry can improve the yield. Changes in muscle protein profiles can occur both pre- and postharvest and constitute an overall characterization of the muscle properties including texture. The aim of this study was to investigate this relationship between specific muscle proteins and the texture...

  19. Forensic identification of severely degraded Atlantic salmon (Salmo salar) and rainbow trout (Oncorhynchus mykiss) tissues.

    Science.gov (United States)

    Dalvin, Sussie; Glover, Kevin A; Sørvik, Anne Ge; Seliussen, Bjørghild B; Taggart, John B

    2010-11-03

    Aquaculture is a globally important and rapidly growing industry. It contributes positively to the economy and sustainability of coastal communities, but it is not without regulatory challenges. These challenges are diverse, and may include identification of fish discarded in an illegal manner, biological discharge from fish ensilage tanks, and partially destroyed or processed tissues. Robust genetic tools are required by management authorities to address these challenges. In this paper, we describe nine species-specific primer sets amplifying very short DNA fragments within the mitochondrial DNA cytochrome c oxidase (COI) gene, which were designed to permit diagnostic identification of degraded DNA from two of the most commonly farmed salmonids in Europe and North America. Of the nine designed primer sets, six were found to be species-specific (four Atlantic salmon, two rainbow trout), whereas the remaining three sets (two Atlantic salmon, one rainbow trout) also amplified a product from other, closely related, salmonid DNA templates. Screening of DNA templates from 11 other non-salmonid native fish species did not produce PCR products with any of the primer sets. Specific tests confirmed the ability of these markers to identify Atlantic salmon and rainbow trout tissues in treated food products, chemically treated ensilage waste and fillets left to degrade in saltwater for up to 31 days at 15°C. Importantly, these markers provided diagnostic identification in cases where other genetic methods failed because of degraded DNA quality. Results from this study demonstrate that amplification of very short DNA fragments using species-specific primers represents a robust and versatile method to create cheap and efficient genetic tests that can be implemented in a range of forensic applications. These markers will provide fishery, aquaculture and food regulatory authorities with a method to investigate and enforce regulations within these industries.

  20. Extraction and characterization of candidate bioactive compounds in different tissues from salmon (Salmo salar)

    DEFF Research Database (Denmark)

    Falkenberg, Susan Skanderup; Mikalsen, S. O.; Joensen, H.

    2014-01-01

    not contain standard unmodified amino acids, indicating peptides with modified amino acids or other kinds of molecules.Industrial relevance. Bioprospecting in fish tissue traditionally regarded as waste can lead to detection of novel natural bioactive compounds including peptides, which could have nutritional...... in several fractions from different tissues but most pronounced in gills. One family was defined according to content of a specific amino acid sequence (PW). Three families were defined by the m/z value of the smallest compound reported in each family (219, 434 and 403). The three latter families did......, pharmaceutical or other functional value and be used in health and functional foods, thus increasing the value adding of secondary marine products. A number of naturally occurring antimicrobial peptides have been characterized from fish skin and gills, such as piscidins, but these and other fish tissues may...

  1. Endocrine systems in juvenile anadromous and landlocked Atlantic salmon (Salmo salar): Seasonal development and seawater acclimation

    Science.gov (United States)

    Nilsen, Tom O.; Ebbesson, Lars O.E.; Kiilerich, P.; Bjornsson, B. Th; Madsen, Steffen S.; McCormick, S.D.; Stefansson, S.O.

    2008-01-01

    The present study compares developmental changes in plasma levels of growth hormone (GH), insulin-like growth factor I (IGF-I) and cortisol, and mRNA levels of their receptors and the prolactin receptor (PRLR) in the gill of anadromous and landlocked Atlantic salmon during the spring parr-smolt transformation (smoltification) period and following four days and one month seawater (SW) acclimation. Plasma GH and gill GH receptor (GHR) mRNA levels increased continuously during the spring smoltification period in the anadromous, but not in landlocked salmon. There were no differences in plasma IGF-I levels between strains, or any increase during smoltification. Gill IGF-I and IGF-I receptor (IGF-IR) mRNA levels increased in anadromous salmon during smoltification, with no changes observed in landlocked fish. Gill PRLR mRNA levels remained stable in both strains during spring. Plasma cortisol levels in anadromous salmon increased 5-fold in May and June, but not in landlocked salmon. Gill glucocorticoid receptor (GR) mRNA levels were elevated in both strains at the time of peak smoltification in anadromous salmon, while mineralocorticoid receptor (MR) mRNA levels remained stable. Only anadromous salmon showed an increase of gill 11??-hydroxysteroid dehydrogenase type-2 (11??-HSD2) mRNA levels in May. GH and gill GHR mRNA levels increased in both strains following four days of SW exposure in mid-May, whereas only the anadromous salmon displayed elevated plasma GH and GHR mRNA after one month in SW. Plasma IGF-I increased after four days in SW in both strains, decreasing in both strains after one month in SW. Gill IGF-I mRNA levels were only increased in landlocked salmon after 4 days in SW. Gill IGF-IR mRNA levels in SW did not differ from FW levels in either strain. Gill PRLR mRNA did not change after four days of SW exposure, and decreased in both strains after one month in SW. Plasma cortisol levels did not change following SW exposure in either strain. Gill GR, 11??-HSD2 and MR mRNA levels increased after four days in SW in both strains, whereas only the anadromous strain maintained elevated gill GR and 11??-HSD2 mRNA levels after one month in SW. The results indicate that hormones and receptors of the GH and cortisol axes are present at significantly lower levels during spring development and SW acclimation in landlocked relative to anadromous salmon. These findings suggest that attenuation of GH and cortisol axes may, at least partially, result in reduced preparatory upregulation of key gill ion-secretory proteins, possibly a result of reduced selection pressure for marine adaptations in landlocked salmon. ?? 2007 Elsevier Inc. All rights reserved.

  2. Endocrine systems in juvenile anadromous and landlocked Atlantic salmon (Salmo salar): Seasonal development and seawater acclimation

    DEFF Research Database (Denmark)

    Nilsen, Tom O; Ebbesson, Lars O E; Kiilerich, Pia

    2008-01-01

    The present study compares developmental changes in plasma levels of growth hormone (GH), insulin-like growth factor I (IGF-I) and cortisol, and mRNA levels of their receptors and the prolactin receptor (PRLR) in the gill of anadromous and landlocked Atlantic salmon during the spring parr-smolt t...

  3. Group behavioural responses of Atlantic salmon (Salmo salar L.) to light, infrasound and sound stimuli.

    Science.gov (United States)

    Bui, Samantha; Oppedal, Frode; Korsøen, Øyvind J; Sonny, Damien; Dempster, Tim

    2013-01-01

    Understanding species-specific flight behaviours is essential in developing methods of guiding fish spatially, and requires knowledge on how groups of fish respond to aversive stimuli. By harnessing their natural behaviours, the use of physical manipulation or other potentially harmful procedures can be minimised. We examined the reactions of sea-caged groups of 50 salmon (1331 ± 364 g) to short-term exposure to visual or acoustic stimuli. In light experiments, fish were exposed to one of three intensities of blue LED light (high, medium and low) or no light (control). Sound experiments included exposure to infrasound (12 Hz), a surface disturbance event, the combination of infrasound and surface disturbance, or no stimuli. Groups that experienced light, infrasound, and the combination of infrasound and surface disturbance treatments, elicited a marked change in vertical distribution, where fish dived to the bottom of the sea-cage for the duration of the stimulus. Light treatments, but not sound, also reduced the total echo-signal strength (indicative of swim bladder volume) after exposure to light, compared to pre-stimulus levels. Groups in infrasound and combination treatments showed increased swimming activity during stimulus application, with swimming speeds tripled compared to that of controls. In all light and sound treatments, fish returned to their pre-stimulus swimming depths and speeds once exposure had ceased. This work establishes consistent, short-term avoidance responses to these stimuli, and provides a basis for methods to guide fish for aquaculture applications, or create avoidance barriers for conservation purposes. In doing so, we can achieve the manipulation of group position with minimal welfare impacts, to create more sustainable practices.

  4. Group behavioural responses of Atlantic salmon (Salmo salar L. to light, infrasound and sound stimuli.

    Directory of Open Access Journals (Sweden)

    Samantha Bui

    Full Text Available Understanding species-specific flight behaviours is essential in developing methods of guiding fish spatially, and requires knowledge on how groups of fish respond to aversive stimuli. By harnessing their natural behaviours, the use of physical manipulation or other potentially harmful procedures can be minimised. We examined the reactions of sea-caged groups of 50 salmon (1331 ± 364 g to short-term exposure to visual or acoustic stimuli. In light experiments, fish were exposed to one of three intensities of blue LED light (high, medium and low or no light (control. Sound experiments included exposure to infrasound (12 Hz, a surface disturbance event, the combination of infrasound and surface disturbance, or no stimuli. Groups that experienced light, infrasound, and the combination of infrasound and surface disturbance treatments, elicited a marked change in vertical distribution, where fish dived to the bottom of the sea-cage for the duration of the stimulus. Light treatments, but not sound, also reduced the total echo-signal strength (indicative of swim bladder volume after exposure to light, compared to pre-stimulus levels. Groups in infrasound and combination treatments showed increased swimming activity during stimulus application, with swimming speeds tripled compared to that of controls. In all light and sound treatments, fish returned to their pre-stimulus swimming depths and speeds once exposure had ceased. This work establishes consistent, short-term avoidance responses to these stimuli, and provides a basis for methods to guide fish for aquaculture applications, or create avoidance barriers for conservation purposes. In doing so, we can achieve the manipulation of group position with minimal welfare impacts, to create more sustainable practices.

  5. 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.

  6. Atlantic salmon (Salmo salar) liver transcriptome response to diets containing Camelina sativa products.

    Science.gov (United States)

    Xue, Xi; Hixson, Stefanie M; Hori, Tiago S; Booman, Marije; Parrish, Christopher C; Anderson, Derek M; Rise, Matthew L

    2015-06-01

    Due to increasing demand for fish oil (FO) and fish meal (FM) in aquafeeds, more sustainable alternatives such as plant-derived oils and proteins are needed. Camelina sativa products are viable feed ingredients given the high oil and crude protein content in the seed. Atlantic salmon were fed diets with complete or partial replacement of FO and/or FM with camelina oil (CO) and/or camelina meal (CM) in a 16-week trial [Control diet: FO; Test diets: 100% CO replacement of FO (100CO), or 100CO with solvent-extracted FM (100COSEFM), 10% CM (100CO10CM), or SEFM+10% CM (100COSEFM10CM)]. Diet composition, growth, and fatty acid analyses for this feeding trial were published previously. A 44K microarray experiment identified liver transcripts that responded to 100COSEFM10CM (associated with reduced growth) compared to controls, yielding 67 differentially expressed features (FDRcamelina-containing diet groups compared with controls. Multivariate statistics were used to correlate hepatic desaturase and elongase gene expression data with tissue fatty acid profiles, indicating the involvement of these genes in LC-PUFA biosynthesis. This nutrigenomic study provides molecular biomarkers for use in developing novel aquafeeds using camelina products. Copyright © 2015 Elsevier Inc. All rights reserved.

  7. Extraction and characterization of naturally occurring bioactive peptides from different tissues from Salmon (Salmo salar)

    DEFF Research Database (Denmark)

    Falkenberg, Susan Skanderup; Nielsen, Henrik Hauch

    2011-01-01

    of secondary marine products. Only few naturally occurring bioactive peptides have been characterized such as the antimicrobial polypeptide piscidines from gills. It is therefore hypothesized, that fish tissue also contains numerous other peptides with other bioactive properties. The approach in this project...... number of bio-components such as bioactive peptides for this purpose. Tissue and proteins from e.g. fish gills, skin and viscera could be a new source of peptides that could have a nutritional and pharmaceutical value, and be used in health and functional foods and thereby increasing the value adding...... is therefore to extract and identify naturally occurring bioactive peptides from different tissues from salmon. A number of aqueous extracts were made from gills, skin and belly flap. In order to preserve the bioactivity of the peptides mild extraction procedures as acidic, basic and aqueous solutions were...

  8. Comparative Genomics Identifies Candidate Genes for Infectious Salmon Anemia (ISA) Resistance in Atlantic Salmon (Salmo salar)

    OpenAIRE

    Li, Jieying; Keith A. Boroevich; Koop, Ben F; Davidson, William S.

    2010-01-01

    Infectious salmon anemia (ISA) has been described as the hoof and mouth disease of salmon farming. ISA is caused by a lethal and highly communicable virus, which can have a major impact on salmon aquaculture, as demonstrated by an outbreak in Chile in 2007. A quantitative trait locus (QTL) for ISA resistance has been mapped to three microsatellite markers on linkage group (LG) 8 (Chr 15) on the Atlantic salmon genetic map. We identified bacterial artificial chromosome (BAC) clones and three f...

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

    DEFF Research Database (Denmark)

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

    2015-01-01

    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...

  10. NFAT5 genes are part of the osmotic regulatory system in Atlantic salmon (Salmo salar).

    Science.gov (United States)

    Lorgen, Marlene; Jorgensen, Even H; Jordan, William C; Martin, Samuel A M; Hazlerigg, David G

    2017-02-01

    The anadromous Atlantic salmon utilizes both fresh and salt water (FW and SW) habitats during its life cycle. The parr-smolt transformation (PST) is an important developmental transition from a FW adapted juvenile parr to a SW adapted smolt. Physiological changes in osmoregulatory tissues, particularly the gill, are key in maintaining effective ion regulation during PST. Changes are initiated prior to SW exposure (preparative phase), and are completed when smolts enter the sea (activational phase) where osmotic stress may directly stimulate changes in gene expression. In this paper we identify 4 nuclear factor of activated T cells (NFAT5, an osmotic stress transcription factor) paralogues in Atlantic salmon, which showed strong homology in characterized functional domains with those identified in other vertebrates. Two of the identified paralogues (NFAT5b1 and NFAT5b2) showed increased expression following transfer from FW to SW. This effect was largest in parr that were maintained under short day photoperiod, and showed the highest increases in chloride ion levels in response to SW exposure. The results of this study suggest that NFAT5 is involved in the osmotic stress response of Atlantic salmon. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

  11. Increased daylength stimulates plasma growth hormone and gill Na+, K+ and -ATPase Atlantic salmon (Salmo salar )

    Science.gov (United States)

    McCormick, S.D.; Bjornsson, Bjorn Thrandur; Sheridan, M.; Eilertson, C.; Carey, J.B.; O'Dea, M.

    1995-01-01

    Atlantic salmon juveniles reared at constant temperature (9–10°C) were exposed to four photoperiod treatment and sampled every 2 weeks from January through May. Fish reared under normal photoperiod exhibited eight-and three fold increases in plasma growth hormone and gill Na+, K+-ATPase activity, respectively, between January and April. Fish exposed to abrupt increases in daylength (LD 15:9) in February or March responded with earlier increases in plasma growth hormone and gill Na+, K+-ATPase activity, and earlier decreases in condition factor relative to fish in the normal photoperiod group. Fish maintained under short daylength (LD 9:15) from January to May exhibited delayed and muted increases in plasma growth hormone and gill Na+, K+-ATPase activity. Plasma thyroxine exhibited a 2.5-fold increase from February to late March in the normal photoperiod group, was generally lower in the LD 9:15 group, but exhibited no obvious response to abrupt increases in daylength. There was an increase in plasma 3,5,3′-triiodo-l-thyronine with time in all groups (43–80%) but no significant response to photoperiod. Plasma levels of somatostatin-25 were highest in the LD 9:15 group, but there was no detectable response to increased daylength in any of the photoperiod treatments. The results indicate that plasma growth hormone is responsive to increased daylength and may be causally related to subsequent increases in gill Na+, K+-ATPase.

  12. Jellyfish as vectors of bacterial disease for farmed salmon (Salmo salar).

    Science.gov (United States)

    Ferguson, Hugh W; Delannoy, Christian M J; Hay, Stephen; Nicolson, James; Sutherland, David; Crumlish, Margaret

    2010-05-01

    Swarms or blooms of jellyfish are increasingly problematic and can result in high mortality rates of farmed fish. Small species of jellyfish, such as Phialella quadrata (13 mm in diameter), are capable of passing through the mesh of sea cages and being sucked into the mouth of fish during respiration. Results of the current study show that the initial damage to gills of farmed Atlantic salmon, likely produced by nematocyst-derived toxins from the jellyfish, was compounded by secondary bacterial infection with Tenacibaculum maritimum. Results also demonstrate that these filamentous bacteria were present on the mouth of the jellyfish and that their DNA sequences were almost identical to those of bacteria present on the salmon gills. This suggests that the bacterial lesions were not the result of an opportunistic infection of damaged tissue, as previously thought. Instead, P. quadrata is probably acting as a vector for this particular bacterial pathogen, and it is the first time that evidence to support such a link has been presented. No prior literature describing the presence of bacteria associated with jellyfish, except studies about their decay, could be found. It is not known if all jellyfish of this and other species carry similar bacteria or the relationship to each other. Their source, the role they play under other circumstances, and indeed whether the jellyfish were themselves diseased are also not known. The high proteolytic capabilities of T. maritimum mean that partially digested gill tissues were readily available to the jellyfish, which rely heavily on intracellular digestion for their nutrition.

  13. Starvation alters the liver transcriptome of the innate immune response in Atlantic salmon (Salmo salar).

    Science.gov (United States)

    Martin, Samuel A M; Douglas, Alex; Houlihan, Dominic F; Secombes, Christopher J

    2010-07-05

    The immune response is an energy demanding process, which has effects in many physiological pathways in the body including protein and lipid metabolism. During an inflammatory response the liver is required to produce high levels of acute phase response proteins that attempt to neutralise an invading pathogen. Although this has been extensively studied in both mammals and fish, little is known about how high and low energy reserves modulate the response to an infection in fish which are ectothermic vertebrates. Food withdrawal in fish causes a decrease in metabolic rate so as to preserve protein and lipid energy reserves, which occurs naturally during the life cycle of many salmonids. Here we investigated how the feeding or fasting of Atlantic salmon affected the transcriptional response in the liver to an acute bacterial infection. Total liver RNA was extracted from four different groups of salmon. Two groups were fed or starved for 28 days. One of each of the fed or starved groups was then exposed to an acute bacterial infection. Twenty four hours later (day 29) the livers were isolated from all fish for RNA extraction. The transcriptional changes were examined by micro array analysis using a 17 K Atlantic salmon cDNA microarray. The expression profiling results showed major changes in gene transcription in each of the groups. Enrichment for particular biological pathways was examined by analysis of gene ontology. Those fish that were starved decreased immune gene transcription and reduced production of plasma protein genes, and upon infection there was a further decrease in genes encoding plasma proteins but a large increase in acute phase response proteins. The latter was greater in magnitude than in the fish that had been fed prior to infection. The expression of several genes that were found altered during microarray analysis was confirmed by real time PCR. We demonstrate that both starvation and infection have profound effects on transcription in the liver of salmon. There was a significant effect on the transcriptional response to infection depending on the prior feeding regime of the fish. It is likely that the energy demands on protein synthesis for acute phase response proteins are relatively high in the starved fish which have reduced energy reserves. This has implications for dietary control of fish if an immune response is anticipated.

  14. Candida utilis and Chlorella vulgaris counteract intestinal inflammation in Atlantic salmon (Salmo salar L..

    Directory of Open Access Journals (Sweden)

    Fabian Grammes

    Full Text Available Intestinal inflammation, caused by impaired intestinal homeostasis, is a serious condition in both animals and humans. The use of conventional extracted soybean meal (SBM in diets for Atlantic salmon and several other fish species is known to induce enteropathy in the distal intestine, a condition often referred to as SBM induced enteropathy (SBMIE. In the present study, we investigated the potential of different microbial ingredients to alleviate SBMIE in Atlantic salmon, as a model of feed-induced inflammation. The dietary treatments consisted of a negative control based on fish meal (FM, a positive control based on 20% SBM, and four experimental diets combining 20% SBM with either one of the three yeasts Candida utilis (CU, Kluyveromyces marxianus (KM, Saccharomyces cerevisiae (SC or the microalgae Chlorella vulgaris (CV. Histopathological examination of the distal intestine showed that all fish fed the SC or SBM diets developed characteristic signs of SBMIE, while those fed the FM, CV or CU diets showed a healthy intestine. Fish fed the KM diet showed intermediate signs of SBMIE. Corroborating results were obtained when measuring the relative length of PCNA positive cells in the crypts of the distal intestine. Gene set enrichment analysis revealed decreased expression of amino acid, fat and drug metabolism pathways as well as increased expression of the pathways for NOD-like receptor signalling and chemokine signalling in both the SC and SBM groups while CV and CU were similar to FM and KM was intermediate. Gene expression of antimicrobial peptides was reduced in the groups showing SBMIE. The characterisation of microbial communities using PCR-DGGE showed a relative increased abundance of Firmicutes bacteria in fish fed the SC or SBM diets. Overall, our results show that both CU and CV were highly effective to counteract SBMIE, while KM had less effect and SC had no functional effects.

  15. 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.

  16. Comparative genomics identifies candidate genes for infectious salmon anemia (ISA) resistance in Atlantic salmon (Salmo salar).

    Science.gov (United States)

    Li, Jieying; Boroevich, Keith A; Koop, Ben F; Davidson, William S

    2011-04-01

    Infectious salmon anemia (ISA) has been described as the hoof and mouth disease of salmon farming. ISA is caused by a lethal and highly communicable virus, which can have a major impact on salmon aquaculture, as demonstrated by an outbreak in Chile in 2007. A quantitative trait locus (QTL) for ISA resistance has been mapped to three microsatellite markers on linkage group (LG) 8 (Chr 15) on the Atlantic salmon genetic map. We identified bacterial artificial chromosome (BAC) clones and three fingerprint contigs from the Atlantic salmon physical map that contains these markers. We made use of the extensive BAC end sequence database to extend these contigs by chromosome walking and identified additional two markers in this region. The BAC end sequences were used to search for conserved synteny between this segment of LG8 and the fish genomes that have been sequenced. An examination of the genes in the syntenic segments of the tetraodon and medaka genomes identified candidates for association with ISA resistance in Atlantic salmon based on differential expression profiles from ISA challenges or on the putative biological functions of the proteins they encode. One gene in particular, HIV-EP2/MBP-2, caught our attention as it may influence the expression of several genes that have been implicated in the response to infection by infectious salmon anemia virus (ISAV). Therefore, we suggest that HIV-EP2/MBP-2 is a very strong candidate for the gene associated with the ISAV resistance QTL in Atlantic salmon and is worthy of further study.

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

    OpenAIRE

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

    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 prom...

  18. A novel totivirus and piscine reovirus (PRV in Atlantic salmon (Salmo salar with cardiomyopathy syndrome (CMS

    Directory of Open Access Journals (Sweden)

    Nederbragt Alexander J

    2010-11-01

    Full Text Available Abstract Background Cardiomyopathy syndrome (CMS is a severe disease affecting large farmed Atlantic salmon. Mortality often appears without prior clinical signs, typically shortly prior to slaughter. We recently reported the finding and the complete genomic sequence of a novel piscine reovirus (PRV, which is associated with another cardiac disease in Atlantic salmon; heart and skeletal muscle inflammation (HSMI. In the present work we have studied whether PRV or other infectious agents may be involved in the etiology of CMS. Results Using high throughput sequencing on heart samples from natural outbreaks of CMS and from fish experimentally challenged with material from fish diagnosed with CMS a high number of sequence reads identical to the PRV genome were identified. In addition, a sequence contig from a novel totivirus could also be constructed. Using RT-qPCR, levels of PRV in tissue samples were quantified and the totivirus was detected in all samples tested from CMS fish but not in controls. In situ hybridization supported this pattern indicating a possible association between CMS and the novel piscine totivirus. Conclusions Although causality for CMS in Atlantic salmon could not be proven for either of the two viruses, our results are compatible with a hypothesis where, in the experimental challenge studied, PRV behaves as an opportunist whereas the totivirus might be more directly linked with the development of CMS.

  19. Autopolyploidy genome duplication preserves other ancient genome duplications in Atlantic salmon (Salmo salar).

    Science.gov (United States)

    Christensen, Kris A; Davidson, William S

    2017-01-01

    Salmonids (e.g. Atlantic salmon, Pacific salmon, and trouts) have a long legacy of genome duplication. In addition to three ancient genome duplications that all teleosts are thought to share, salmonids have had one additional genome duplication. We explored a methodology for untangling these duplications from each other to better understand them in Atlantic salmon. In this methodology, homeologous regions (paralogous/duplicated genomic regions originating from a whole genome duplication) from the most recent genome duplication were assumed to have duplicated genes at greater density and have greater sequence similarity. This assumption was used to differentiate duplicated gene pairs in Atlantic salmon that are either from the most recent genome duplication or from earlier duplications. From a comparison with multiple vertebrate species, it is clear that Atlantic salmon have retained more duplicated genes from ancient genome duplications than other vertebrates--often at higher density in the genome and containing fewer synonymous mutations. It may be that polysomic inheritance is the mechanism responsible for maintaining ancient gene duplicates in salmonids. Polysomic inheritance (when multiple chromosomes pair during meiosis) is thought to be relatively common in salmonids compared to other vertebrate species. These findings illuminate how genome duplications may not only increase the number of duplicated genes, but may also be involved in the maintenance of them from previous genome duplications as well.

  20. 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

    Vaccination of sea-ranched Atlantic salmon was conducted in order to investigate if immunoprophylactic measures could improve their survival. Fish were either vaccinated by bath or injection. A total of 66 000 fish were reared in fresh water at a hatchery on the island of Bornholm and at the pres......Vaccination of sea-ranched Atlantic salmon was conducted in order to investigate if immunoprophylactic measures could improve their survival. Fish were either vaccinated by bath or injection. A total of 66 000 fish were reared in fresh water at a hatchery on the island of Bornholm...

  1. Extraction and characterisation of gelatine from Atlantic salmon (Salmo salar) skin.

    Science.gov (United States)

    Arnesen, Jan Arne; Gildberg, Asbjørn

    2007-01-01

    Gelatine was extracted from Atlantic salmon and Atlantic cod skin by the acid extraction process. After filtration and ion exchange treatment the extracts were colourless and free from fishy odour. In three separate experiments the average yields of gelatine from salmon and cod skins were 39.7% (+/-2.2%) and 44.8% (+/-0.2%) respectively, on a dry matter basis. Gelatine from salmon contained slightly more hydroxyproline and proline (16.6%) than cod gelatine (15.4%), whereas the content of serine was lower (4.6% versus 6.3%). Salmon gelatine expressed slightly higher gelling temperature (12 degrees C) than cod gelatine (10 degrees C), and higher initial gel strength. During storage at 10 degrees C, gel strengths were increased and more so with gels made from cod than from salmon gelatine. Hence, gels made from cod and salmon gelatines extracted at 56 degrees C achieved the same gel strength (195g) after 7days of storage. Gelatines extracted at a higher temperature (65 degrees C) gave lower gel strengths.

  2. Testes and brain gene expression in precocious male and adult maturing Atlantic salmon (Salmo salar)

    Science.gov (United States)

    2010-01-01

    Background The male Atlantic salmon generally matures in fresh water upon returning after one or several years at sea. Some fast-growing male parr develop an alternative life strategy where they sexually mature before migrating to the oceans. These so called 'precocious' parr or 'sneakers' can successfully fertilise adult female eggs and so perpetuate their line. We have used a custom-built cDNA microarray to investigate gene expression changes occurring in the salmon gonad and brain associated with precocious maturation. The microarray has been populated with genes selected specifically for involvement in sexual maturation (precocious and adult) and in the parr-smolt transformation. Results Immature and mature parr collected from a hatchery-reared stock in January were significantly different in weight, length and condition factor. Changes in brain expression were small - never more than 2-fold on the microarray, and down-regulation of genes was much more pronounced than up-regulation. Significantly changing genes included isotocin, vasotocin, cathepsin D, anamorsin and apolipoprotein E. Much greater changes in expression were seen in the testes. Among those genes in the testis with the most significant changes in expression were anti-Mullerian hormone, collagen 1A, and zinc finger protein (Zic1), which were down-regulated in precocity and apolipoproteins E and C-1, lipoprotein lipase and anti-leukoproteinase precursor which were up-regulated in precocity. Expression changes of several genes were confirmed in individual fish by quantitative PCR and several genes (anti-Mullerian hormone, collagen 1A, beta-globin and guanine nucleotide binding protein (G protein) beta polypeptide 2-like 1 (GNB2L1) were also examined in adult maturing testes. Down-regulation of anti-Mullerian hormone was judged to be greater than 160-fold for precocious males and greater than 230-fold for November adult testes in comparison to July testes by this method. For anti-Mullerian hormone and guanine nucleotide binding protein beta polypeptide 2-like 1 expression changes in precocious males mirrored mature adults (November) but for collagen 1A and beta-globin the pattern was more complex. Conclusions Expression changes in the fish brain during the process of precocious sexual maturation were small compared to those in the testes. Microarray analysis suggested down-regulation of housekeeping functions and up-regulation of a small number of specific processes. Transcriptional changes in the testes were much more pronounced with anti-Mullerian hormone playing a major role. Expression profiles for mature parr and maturing adult testes indicate subtle differences in gene expression between these two related groups. PMID:20350334

  3. Testes and brain gene expression in precocious male and adult maturing Atlantic salmon (Salmo salar).

    Science.gov (United States)

    Guiry, Aoife; Flynn, Denis; Hubert, Sophie; O'Keeffe, Allan M; LeProvost, Olivier; White, Samantha L; Forde, Patrick F; Davoren, Pamela; Houeix, Benoit; Smith, Terry J; Cotter, Deirdre; Wilkins, Noel P; Cairns, Michael T

    2010-03-30

    The male Atlantic salmon generally matures in fresh water upon returning after one or several years at sea. Some fast-growing male parr develop an alternative life strategy where they sexually mature before migrating to the oceans. These so called 'precocious' parr or 'sneakers' can successfully fertilise adult female eggs and so perpetuate their line. We have used a custom-built cDNA microarray to investigate gene expression changes occurring in the salmon gonad and brain associated with precocious maturation. The microarray has been populated with genes selected specifically for involvement in sexual maturation (precocious and adult) and in the parr-smolt transformation. Immature and mature parr collected from a hatchery-reared stock in January were significantly different in weight, length and condition factor. Changes in brain expression were small - never more than 2-fold on the microarray, and down-regulation of genes was much more pronounced than up-regulation. Significantly changing genes included isotocin, vasotocin, cathepsin D, anamorsin and apolipoprotein E. Much greater changes in expression were seen in the testes. Among those genes in the testis with the most significant changes in expression were anti-Mullerian hormone, collagen 1A, and zinc finger protein (Zic1), which were down-regulated in precocity and apolipoproteins E and C-1, lipoprotein lipase and anti-leukoproteinase precursor which were up-regulated in precocity. Expression changes of several genes were confirmed in individual fish by quantitative PCR and several genes (anti-Mullerian hormone, collagen 1A, beta-globin and guanine nucleotide binding protein (G protein) beta polypeptide 2-like 1 (GNB2L1) were also examined in adult maturing testes. Down-regulation of anti-Mullerian hormone was judged to be greater than 160-fold for precocious males and greater than 230-fold for November adult testes in comparison to July testes by this method. For anti-Mullerian hormone and guanine nucleotide binding protein beta polypeptide 2-like 1 expression changes in precocious males mirrored mature adults (November) but for collagen 1A and beta-globin the pattern was more complex. Expression changes in the fish brain during the process of precocious sexual maturation were small compared to those in the testes. Microarray analysis suggested down-regulation of housekeeping functions and up-regulation of a small number of specific processes. Transcriptional changes in the testes were much more pronounced with anti-Mullerian hormone playing a major role. Expression profiles for mature parr and maturing adult testes indicate subtle differences in gene expression between these two related groups.

  4. Testes and brain gene expression in precocious male and adult maturing Atlantic salmon (Salmo salar

    Directory of Open Access Journals (Sweden)

    Houeix Benoit

    2010-03-01

    Full Text Available Abstract Background The male Atlantic salmon generally matures in fresh water upon returning after one or several years at sea. Some fast-growing male parr develop an alternative life strategy where they sexually mature before migrating to the oceans. These so called 'precocious' parr or 'sneakers' can successfully fertilise adult female eggs and so perpetuate their line. We have used a custom-built cDNA microarray to investigate gene expression changes occurring in the salmon gonad and brain associated with precocious maturation. The microarray has been populated with genes selected specifically for involvement in sexual maturation (precocious and adult and in the parr-smolt transformation. Results Immature and mature parr collected from a hatchery-reared stock in January were significantly different in weight, length and condition factor. Changes in brain expression were small - never more than 2-fold on the microarray, and down-regulation of genes was much more pronounced than up-regulation. Significantly changing genes included isotocin, vasotocin, cathepsin D, anamorsin and apolipoprotein E. Much greater changes in expression were seen in the testes. Among those genes in the testis with the most significant changes in expression were anti-Mullerian hormone, collagen 1A, and zinc finger protein (Zic1, which were down-regulated in precocity and apolipoproteins E and C-1, lipoprotein lipase and anti-leukoproteinase precursor which were up-regulated in precocity. Expression changes of several genes were confirmed in individual fish by quantitative PCR and several genes (anti-Mullerian hormone, collagen 1A, beta-globin and guanine nucleotide binding protein (G protein beta polypeptide 2-like 1 (GNB2L1 were also examined in adult maturing testes. Down-regulation of anti-Mullerian hormone was judged to be greater than 160-fold for precocious males and greater than 230-fold for November adult testes in comparison to July testes by this method. For anti-Mullerian hormone and guanine nucleotide binding protein beta polypeptide 2-like 1 expression changes in precocious males mirrored mature adults (November but for collagen 1A and beta-globin the pattern was more complex. Conclusions Expression changes in the fish brain during the process of precocious sexual maturation were small compared to those in the testes. Microarray analysis suggested down-regulation of housekeeping functions and up-regulation of a small number of specific processes. Transcriptional changes in the testes were much more pronounced with anti-Mullerian hormone playing a major role. Expression profiles for mature parr and maturing adult testes indicate subtle differences in gene expression between these two related groups.

  5. Effects on salmon (Salmo salar) from different operational procedures in fish farming

    OpenAIRE

    Bjordal, Åsmund; Fernö, Anders; Furevik, Dag M.; Huse, Ingvar

    1988-01-01

    The effects on farmed salmon caused by operational procedures as handling, de-lousing, removal of dead fish, grading and transfer were studied by underwater TV-observations, ultrasonic telemetry of heart rate and analyses of blood cortisol level. Handling and de-lousing were identified as important stressors.

  6. Vaccination and triploidy increase relative heart weight in farmed Atlantic salmon, Salmo salar L.

    Science.gov (United States)

    Fraser, T W K; Mayer, I; Hansen, T; Poppe, T T; Skjaeraasen, J E; Koppang, E O; Fjelldal, P G

    2015-02-01

    Heart morphology is particularly plastic in teleosts and differs between farmed and wild Atlantic salmon. However, little is known about how different culture practices and sex affect heart morphology. This study investigated how vaccination, triploidy and sex affected heart size and heart morphology (ventricle shape, angle of the bulbus arteriosus) in farmed Atlantic salmon for 18 months following vaccination (from c. 50-3000 g body weight). In addition, hearts were examined histologically after 7 months in sea water. All fish sampled were sexually immature. Vaccinated fish had significantly heavier hearts relative to body weight and a more triangular ventricle than unvaccinated fish, suggesting a greater cardiac workload. Irrespective of time, triploids had significantly heavier hearts relative to body weight, a more acute angle of the bulbus arteriosus and less fat deposition in the epicardium than diploids. The ventricle was also more triangular in triploids than diploids at seawater transfer. Sex had transient effects on the angle of the bulbus arteriosus, but no effect on relative heart weight or ventricle shape. From a morphological perspective, the results indicate that vaccination and triploidy increase cardiac workload in farmed Atlantic salmon. © 2014 John Wiley & Sons Ltd.

  7. Soybean meal-induced enteritis in Atlantic salmon (Salmo salar L.) at different temperatures

    NARCIS (Netherlands)

    Urán, P.; Schrama, J.W.; Rombout, J.H.W.M.; Obach, A.; Jensen, L.; Koppe, W.; Verreth, J.A.J.

    2008-01-01

    This study evaluates the effect of temperature on the development of intestinal disorders when Atlantic salmon are fed soybean meal (SBM). In this study 20% of the dietary fishmeal was replaced by solvent-extracted Hipro SBM. Atlantic salmon reared at two different water temperatures (8¿°C and

  8. Effects of photoperiod and melatonin implants on feed intake in Atlantic salmon (Salmo salar L. postsmolts

    Directory of Open Access Journals (Sweden)

    Silvia Maiolo

    2015-12-01

    Full Text Available High melatonin concentrations were expected to negatively affect Atlantic salmon appetite. Hence, individually kept Atlantic salmon postsmolts were subjected to continuous light (24:0, L:L or natural daylight (12:12, L:D and then given intraperitoneal implants of slow release melatonin in a 2 by 2 factorial design. Possible effects on food intake were monitored over three weeks. In addition, a plasma melatonin assessment test was run in parallel to monitor diurnal blood levels of melatonin through the trial. The surgical intervention was effective, leading to a 10x increase in mean melatonin levels when compared to control fish, but neither the implant nor the change in daylight had any significant effect on feed intake, at least in the short term.

  9. Taxonomy Icon Data: Atlantic salmon [Taxonomy Icon

    Lifescience Database Archive (English)

    Full Text Available _salar_NL.png Salmo_salar_S.png Salmo_salar_NS.png http://biosciencedbc.jp/taxonomy_icon/icon.cgi?i=Salmo+sa...lar&t=L http://biosciencedbc.jp/taxonomy_icon/icon.cgi?i=Salmo+salar&t=NL http://biosciencedbc.jp/taxonomy_i...con/icon.cgi?i=Salmo+salar&t=S http://biosciencedbc.jp/taxonomy_icon/icon.cgi?i=Salmo+salar&t=NS ...

  10. Forecasting with Option-Implied Information

    DEFF Research Database (Denmark)

    Christoffersen, Peter; Jacobs, Kris; Chang, Bo Young

    2013-01-01

    of the future realization of the underlying risky asset price can utilize option-implied information in a well-defined manner. Going beyond the univariate option-implied density, we also consider results on option-implied covariance, correlation and beta forecasting, as well as the use of option...

  11. 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.

  12. Option-implied measures of equity risk

    DEFF Research Database (Denmark)

    Chang, Bo-Young; Christoffersen, Peter; Vainberg, Gregory

    2012-01-01

    Equity risk measured by beta is of great interest to both academics and practitioners. Existing estimates of beta use historical returns. Many studies have found option-implied volatility to be a strong predictor of future realized volatility. We find that option-implied volatility and skewness...... are also good predictors of future realized beta. Motivated by this finding, we establish a set of assumptions needed to construct a beta estimate from option-implied return moments using equity and index options. This beta can be computed using only option data on a single day. It is therefore potentially...

  13. Implied terms in English and Romanian law

    Directory of Open Access Journals (Sweden)

    Stefan Dinu

    2015-12-01

    Full Text Available This study analyses the matter of implied terms from the point of view of both English and Romanian law. First, the introductory section provides a brief overview of implied terms, by defining this class of contractual clauses and by providing their general features. Second, the English law position is analysed, where it is generally recognised that a term may be implied in one of three manners, which are described in turn. An emp hasis is made on the Privy Council’s decision in Attorney General of Belize v Belize Telecom Ltd and its impact. Third, the Romanian law position is described, the starting point of the discussion being represented by the provisions of Article 1272 of the 2009 Civil Code. Fourth, the study ends by mentioning some points of comparison between the two legal systems in what concerns the approach towards implied terms.

  14. Сравнительный анализ структурно-функциональной организации головного мозга лососевых рыб. Сообщение I. Атлантический лосось Salmo salar L

    OpenAIRE

    Обухов, Дмитрий; Обухова, Евгения; Пущина, Евгения

    2010-01-01

    В работе проведено исследование цитоархитектоники и нейронной структуры конечного мозга атлантического лосося семги Salmo salar L. Показано, что по уровню дифференциров-ки конечный мозг семги занимает промежуточное положение между хрящевыми ганоидами и высшими костистыми рыбами. Нейронная дифференцировка также достаточно низкая основная масса нейронов относится к разновидностям неспециализированных изодендритных нейронов. Это веерообразные и радиальные шипиковые полимодальные нейроны. В данно...

  15. Processing of real and implied motion

    NARCIS (Netherlands)

    Lorteije, J.A.M.

    2006-01-01

    Processing of real and implied motion We readily recognize whether an animal, person or object within a photograph was moving or standing motionless at the moment the photograph was taken. Photographers, painters, sculptures and cartoonist can successfully convey motion information, even though

  16. 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

    High mortality-rates of seaward migrating salmonid smelts when passing reservoirs and lakes have earlier been found in the Danish River Gudena watershed. To reveal the causes of mortality of migrating smelts in Lake Tange, a 12 km long, shallow reservoir, 50 salmon smelts and 24 trout smelts were...... of death was determined. During the 3-week period, 90% of the tagged smelts died. The main cause of death for both trout and salmon was predation from fish and birds. The most important predator was pike (Esox lucius L.), being responsible for 56% of the observed mortality. Avian predators were assumed...... to be responsible for 31% of the observed mortality. No trout smelts left the reservoir, but 5 salmon-smelts got out through the turbines. Others did traverse the reservoir, but were unable to enter the river downstream, and were later eaten. The present results suggest that mortalities for migrating smolts through...

  17. AS MALDIÇÕES NOS SALMOS

    Directory of Open Access Journals (Sweden)

    Luís I. J. Stadelmann

    1988-01-01

    Full Text Available O livro dos Salmos não goza da admiração unânime dos leitores. Enquanto alguns o apreciam como fonte rica e inesgotável para conhecer a mentalidade religiosa do povo israelita, outros têm sérias ressalvas quanto à sua utilização como livro de oração. Sentem-se ludibriados pela erudição dos comentaristas em suas explicações da forma poética desses textos que exprimem as experiências religiosas dos salmistas, mas não resolvem o problema de fundo que se refere à comunicação do homem com Deus. Pois pela recitação dos Salmos o israelita se punha em contato com Deus pela mediação verbal das idéias e dos sentimentos aí formulados que o elevavam ao âmbito transcendente.

  18. Quantum Darwinian Evolution Implies Tumor Origination

    Science.gov (United States)

    Cooper, W. Grant

    2011-03-01

    Quantum uncertainty limits operating on metastable amino DNA protons drive the arrangement, keto-amino ? enol-imine, which contributes to time-dependent stochastic mutations. Product enol-imine protons participate in coupled quantum oscillations at frequencies of about 1013 s-1 until ``measured by'' an evolutionarily selected quantum reader, the transcriptase. This introduces entanglement states between coherent protons and transcriptase components, which ultimately yield an ensemble of decohered, non-reequilibrated enol and imine isomers that participate in ``molecular clock'' base substitutions at G'-C' and *G-*C sites. This introduces a quantum Darwinian evolution model which (a) simulates incidence of cancer data and (b) implies insight into quantum origins of evolutionary extinction. Data identify an inherited ``genetic space,'' s, which is initially mutation-free and satisfies the inequality, 1 = s = 0.97. When accumulated stochastic mutations cause s-values to approach their evolutionarily allowed threshold limit, s 0.97 + e, age-related degenerative disease is manifested. This implies a gain in evolutionary advantage which protects the gene pool against acquiring unsafe levels of mutation. Data requiring coherent states imply that classical duplex DNA contains an embedded microphysical subset of electron lone-pairs and hydrogen bonded protons that govern time-dependent genetic specificity in terms of quantum probability laws.

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

    Directory of Open Access Journals (Sweden)

    Frederick Harry Pitts

    2014-04-01

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

  20. Asset allocation using option-implied moments

    Science.gov (United States)

    Bahaludin, H.; Abdullah, M. H.; Tolos, S. M.

    2017-09-01

    This study uses an option-implied distribution as the input in asset allocation. The computation of risk-neutral densities (RND) are based on the Dow Jones Industrial Average (DJIA) index option and its constituents. Since the RNDs estimation does not incorporate risk premium, the conversion of RND into risk-world density (RWD) is required. The RWD is obtained through parametric calibration using the beta distributions. The mean, volatility, and covariance are then calculated to construct the portfolio. The performance of the portfolio is evaluated by using portfolio volatility and Sharpe ratio.

  1. 17-Beta estradiol and 4-nonylphenol delay smolt development and downstream migration in Atlantic salmon, Salmo salar

    DEFF Research Database (Denmark)

    Madsen, Steffen S; Skovbølling, Søren; Nielsen, Christian

    2004-01-01

    . Serum vitellogenin levels increased several-fold in both male and female E2- and 4-NP-treated fish. Overall, E2- and 4-NP-treatment impaired smolting as judged by elevated condition factor, reduced gill Na+, K+ -ATPase activity and alpha-subunit Na+, K+ -ATPase mRNA level, reduced muscle water content......The effect of 17-beta estradiol (E2) and 4-nonylphenol (4-NP) on smoltification and downstream migration of Atlantic salmon was studied in an integrated laboratory and field study. In a stock of hatchery-raised 1-year-old salmon, smoltification progressed from February until late May as judged...

  2. Matrilinear phylogeography of Atlantic salmon ( Salmo salar L.) in Europe and postglacial colonization of the Baltic Sea area

    DEFF Research Database (Denmark)

    Nilsson, J.; Gross, R.; Asplund, T.

    2001-01-01

    Sixty-four samples from 46 salmon populations totalling 2369 specimens were used for polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis of the mitochondrial ND1 region. The final analyses included 3095 specimens from 60 populations in Northern Europe. A subsamp...

  3. The effect of thermal acclimation on aerobic scope and critical swimming speed in Atlantic salmon, Salmo salar.

    Science.gov (United States)

    Hvas, Malthe; Folkedal, Ole; Imsland, Albert; Oppedal, Frode

    2017-08-01

    The Atlantic salmon is extensively studied owing to conservation concerns and its economic importance in aquaculture. However, a thorough report of their aerobic capacity throughout their entire thermal niche has not been described. In this study, Atlantic salmon (∼450 g) were acclimated for 4 weeks at 3, 8, 13, 18 or 23°C, and then tested in a large Brett-type swimming respirometer in groups of 10 per trial. Both standard metabolic rate and active metabolic rate continued to increase with temperature, which resulted in an aerobic scope that also increased with temperature, but was statistically similar between 13, 18 and 23°C. The critical swimming speed peaked at 18°C (93.1±1.2 cm s-1), and decreased significantly at the extreme temperatures to 74.8±0.5 and 84.8±1.6 cm s-1 at 3 and 23°C, respectively. At 23°C, the accumulated mortality reached 20% over 4 weeks, while no fish died during acclimation at colder temperatures. Furthermore, fish at 23°C had poor appetite and lower condition factor despite still having a high aerobic scope, suggesting that oxygen uptake was not the limiting factor in the upper thermal niche boundary. In conclusion, Atlantic salmon were able to maintain a high aerobic capacity and good swimming capabilities throughout the entire thermal interval tested, thus demonstrating a high level of flexibility in respiratory capacity towards different temperature exposures. © 2017. Published by The Company of Biologists Ltd.

  4. Cardiac pathological changes of Atlantic salmon (Salmo salar L.) affected with heart and skeletal muscle inflammation (HSMI)

    DEFF Research Database (Denmark)

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

    2012-01-01

    Heart and skeletal muscle inflammation (HSMI) is a disease of marine farmed Atlantic salmon where the pathological changes associated with the disease involve necrosis and an infiltration of inflammatory cells into different regions of the heart and skeletal muscle. The aim of this work...... was to characterize cardiac changes and inflammatory cell types associated with a clinical HSMI outbreak in Atlantic salmon using immunohistochemistry. Different immune cells and cardiac tissue responses associated with the disease were identified using different markers. The spectrum of inflammatory cells associated...... immunostaining was observed for major histocompatibility complex (MHC) class II in HSMI hearts. Although low in number, a few positive cells in diseased hearts were detected using the mature myeloid cell line granulocytes/monocytes antibody indicating more positive cells in diseased than non-diseased hearts...

  5. 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

    of structurally enriched trays. We show that increased structural complexity during early rearing increased brain size in all investigated brain substructures. However, these effects disappeared over time after transfer to barren tanks for external feeding. Parallel to the hatchery study, a group of salmon parr...... 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...

  6. 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

    ... space and diverse, abundant food resources to support growth and survival; waterways that allow for free... diverse food resources to support growth and survival of Atlantic salmon parr; (viii) Freshwater and... HUC 10 Name Status Economic (E), Military (M), orTribal (T) exclusions 1 0102000101 North Branch...

  7. Bioaccumulation of Lead In Body Tissues of Atlantic Salmon (Salmo Salar L: Experimental Investigation and Comparative Analysis

    Directory of Open Access Journals (Sweden)

    Raimondas Leopoldas Idzelis

    2012-12-01

    Full Text Available The article presents tests on one-year artificially bred Atlantic salmon. For 14 days, fish were exposed to lead nitrate Pb (NO32 under concentration corresponding to the highest allowable standard of inland water making 0.005 mg Pb/l. Lead (Pb in fish tissues (muscle and gills was determined applying atomic absorption spectrophotometry (AAS. The obtained results have showed that the maximum-permissible-amount of lead in fish (MPA = 0.2 mg Pb/kg (Lithuanian Hygiene Standard HN 54:2003 slightly exceeds in salmon gills (0.237 mg/kg, whereas in muscles, it exceeds more than twice (0.4 mg/kg. The received data have been compared with the results of the previous studies, where under the same experimental conditions, the bioaccumulation of lead in five types of fish, including roach, perch, rainbow trout, stone loach and gibel carp has been investigated. The conducted research has also revealed that different fish species quite differently accumulate lead while MPA has exceeded in the body tissues of a number of fish, i.e., in the majority of cases, it can be attributed to salmon and stone loach muscles and gills. When observing water bodies, the collected experimental data completely coincide with the results of studies on lead bioaccumulation in fish.Article in Lithuanian

  8. Moritella viscosus infected Atlantic salmon (Salmo salar) express genes during infection associated with quality changes after recovery

    DEFF Research Database (Denmark)

    Ingerslev, Hans-Christian; Nielsen, Michael Engelbrecht

    The gram-negative bacterium Moritella viscosus comprise a huge problem for farmed salmonid fish during cold periods and is the main aetiological agent of winter ulcers. Infection by M. viscosus causes excessive development of punctual lesions in the musculature of the fish, which can cover large...... parts of the body. Infected fish are able to recover and regenerate new skin despite previously heavy wounding. Recovery usually occurs when the water temperature rises above 10-12 °C or the salinity of the water decrease below 12-15 ‰. Regardless of surface/skin recovery, the underlying musculature can...

  9. 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...

  10. Genome wide response to dietary tetradecylthioacetic acid supplementation in the heart of Atlantic Salmon (Salmo salar L

    Directory of Open Access Journals (Sweden)

    Grammes Fabian

    2012-05-01

    Full Text Available Abstract Background Under-dimensioned hearts causing functional problems are associated with higher mortality rates in intensive Atlantic salmon aquaculture. Previous studies have indicated that tetradecylthioacetic acid (TTA induces cardiac growth and also stimulates transcription of peroxisome proliferator activated receptors (PPAR αand βin the Atlantic salmon heart. Since cardiac and transcriptional responses to feed are of high interest in aquaculture, the objective of this study was to characterize the transcriptional mechanisms induced by TTA in the heart of Atlantic salmon. Results Atlantic salmon were kept at sea for 17 weeks. During the first 8 weeks the fish received a TTA supplemented diet. Using microarrays, profound transcriptional effects were observed in the heart at the end of the experiment, 9 weeks after the feeding of TTA stopped. Approximately 90% of the significant genes were expressed higher in the TTA group. Hypergeometric testing revealed the over-representation of 35 gene ontology terms in the TTA fed group. The GO terms were generally categorized into cardiac performance, lipid catabolism, glycolysis and TCA cycle. Conclusions Our results indicate that TTA has profound effects on cardiac performance based on results from microarray and qRT-PCR analysis. The gene expression profile favors a scenario of ”physiological”lright hypertrophy recognized by increased oxidative fatty acid metabolism, glycolysis and TCA cycle activity as well as cardiac growth and contractility in the heart ventricle. Increased cardiac efficiency may offer significant benefits in the demanding Aquaculture situations.

  11. Present-day genetic structure of Atlantic salmon (Salmo salar in Icelandic rivers and ice-cap retreat models.

    Directory of Open Access Journals (Sweden)

    Kristinn Olafsson

    Full Text Available Due to an improved understanding of past climatological conditions, it has now become possible to study the potential concordance between former climatological models and present-day genetic structure. Genetic variability was assessed in 26 samples from different rivers of Atlantic salmon in Iceland (total of 2,352 individuals, using 15 microsatellite loci. F-statistics revealed significant differences between the majority of the populations that were sampled. Bayesian cluster analyses using both prior information and no prior information on sampling location revealed the presence of two distinguishable genetic pools - namely, the Northern (Group 1 and Southern (Group 2 regions of Iceland. Furthermore, the random permutation of different allele sizes among allelic states revealed a significant mutational component to the genetic differentiation at four microsatellite loci (SsaD144, Ssa171, SSsp2201 and SsaF3, and supported the proposition of a historical origin behind the observed variation. The estimated time of divergence, using two different ABC methods, suggested that the observed genetic pattern originated from between the Last Glacial Maximum to the Younger Dryas, which serves as additional evidence of the relative immaturity of Icelandic fish populations, on account of the re-colonisation of this young environment following the Last Glacial Maximum. Additional analyses suggested the presence of several genetic entities which were likely to originate from the original groups detected.

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

    Science.gov (United States)

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

    2014-01-01

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

  13. Enhancement of anti-Aeromonas salmonicida activity in Atlantic salmon (Salmo salar) macrophages by a mannose-binding lectin

    Science.gov (United States)

    Ottinger, C.A.; Johnson, S.C.; Ewart, K.V.; Brown, L.L.; Ross, N.W.

    1999-01-01

    We investigated the effects of a calcium-dependent mannose-binding lectin isolated from the serum of Atlantic salmon on Aeromonassalmonicida viability and the anti-A. salmonicida activity of Atlantic salmon macrophages. In the absence of other factors, binding of this lectin at concentrations of 0.8, 4.0 and 20.0 ng ml−1 to virulent A. salmonicida failed to significantly reduce (P>0.05) cell viability. However, binding of the lectin to A. salmonicida did result in significant (P≤0.05) dose-dependent increases in phagocytosis, and bactericidal activity. Significant increases (P≤0.05) were also observed in phagocyte respiratory burst activity within the lectin concentration range of 4.0–20.0 ng ml−1 but the stimulation was not dose dependent at these lectin concentrations. At the lowest lectin concentration tested (0.32 ng ml−1), a significant decrease (P≤0.05) in respiratory burst was observed. The structure and activity of this lectin are similar to that of mammalian mannose-binding lectins, which are known to play a pivotal role in innate immunity. The presence of this lectin may be an important defense mechanism against Gram-negative bacteria such as A. salmonicida.

  14. Effects of Cortisol on the Intestinal Mucosal Immune Response during Cohabitant Challenge with IPNV in Atlantic Salmon (Salmo salar)

    DEFF Research Database (Denmark)

    Niklasson, Lars; Sundh, Henrik; Olsen, Rolf-Erik

    2014-01-01

    Infectious pancreatic necrosis virus (IPNV) causes high incidence of disease in salmonids during the first period after SW transfer. During this period as well as during periods of stress, cortisol levels increase and indications of a relationship between IPNV susceptibility and cortisol have been...... suggested. The intestine is an entry route and a target tissue for IPNV displaying severe enteritis and sloughing of the mucosa in infected fish. The mechanisms behind effects of the virus on the intestinal tissue and the impact of cortisol on the effect remain unclear. In the present study, Atlantic salmon...... post smolts treated with or without slow release cortisol implants were subjected to a cohabitant IPNV challenge. Analysis of genes and proteins related to the innate and acquired immune responses against virus was performed 6 days post-challenge using qPCR and immunohistochemistry. An increased m...

  15. Genetic architecture of threshold reaction norms for male alternative reproductive tactics in Atlantic salmon (Salmo salar L.)

    National Research Council Canada - National Science Library

    Olivier Lepais; Aurélie Manicki; Stéphane Glise; Mathieu Buoro; Agnès Bardonnet

    2017-01-01

    .... Here, we study the genetic effect and architecture of the variability in reproductive tactics among Atlantic salmon males which can either mature sexually early in life in freshwater or more commonly...

  16. Genetic architecture of threshold reaction norms for male alternative reproductive tactics in Atlantic salmon (Salmo salar L.).

    Science.gov (United States)

    Lepais, Olivier; Manicki, Aurélie; Glise, Stéphane; Buoro, Mathieu; Bardonnet, Agnès

    2017-03-10

    Alternative mating tactics have important ecological and evolutionary implications and are determined by complex interactions between environmental and genetic factors. Here, we study the genetic effect and architecture of the variability in reproductive tactics among Atlantic salmon males which can either mature sexually early in life in freshwater or more commonly only after completing a migration at sea. We applied the latent environmental threshold model (LETM), which provides a conceptual framework linking individual status to a threshold controlling the decision to develop alternative traits, in an innovative experimental design using a semi-natural river which allowed for ecologically relevant phenotypic expression. Early male parr maturation rates varied greatly across families (10 to 93%) which translated into 90% [64-100%] of the phenotypic variation explained by genetic variation. Three significant QTLs were found for the maturation status, however only one collocated with a highly significant QTL explaining 20.6% of the variability of the maturation threshold located on chromosome 25 and encompassing a locus previously shown to be linked to sea age at maturity in anadromous Atlantic salmon. These results provide new empirical illustration of the relevance of the LETM for a better understanding of alternative mating tactics evolution in natural populations.

  17. Environmental contaminants in fillets of sea-run Atlantic salmon (Salmo salar) from the Gulf of Maine Distinct Population Segment

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Between 2008 and 2010, skin‐on fillets from seven dead adult sea‐run Atlantic salmon from the Gulf of Maine Distinct Population Segment (GOM DPS) were analyzed for...

  18. Early nutritional intervention can improve utilisation of vegetable-based diets in diploid and triploid Atlantic salmon (Salmo salar L.).

    Science.gov (United States)

    Clarkson, Michael; Migaud, Herve; Metochis, Christoforos; Vera, Luisa M; Leeming, Daniel; Tocher, Douglas R; Taylor, John F

    2017-07-01

    The present study investigated nutritional programming in Atlantic salmon to improve utilisation of a vegetable-based diet. At first exogenous feeding, fry were fed either a marine-based diet (Diet Mstimulus, 80% fishmeal (FM)/4% fish oil (FO)) or a vegetable-based diet (Diet Vstimulus, 10% FM/0% FO) for 3 weeks. Subsequently, all fish were then fed under the same conditions with a commercial, marine-based, diet for 15 weeks and thereafter challenged with a second V diet (Diet Vchallenge, 10% FM/0% FO) for 6 weeks. Diploid and triploid siblings were run in parallel to examine ploidy effects. Growth performance, feed intake, nutrient utilisation and intestinal morphology were monitored. Fish initially given Diet Vstimulus (V-fish) showed 24 % higher growth rate and 23 % better feed efficiency compared with M-fish when later challenged with Diet Vchallenge. There was no difference in feed intake between nutritional histories, but increased nutrient retentions highlighted the improved utilisation of a V diet in V-fish. There were generally few significant effects of nutritional history or ploidy on enteritis scores in the distal intestine after the challenge phase as only V-triploids showed a significant increase (Pnutritional programming and the ability to respond better when challenged later in life may be attributed to physiological and/or metabolic changes induced by the stimulus. This novel study showed the potential of nutritional programming to improve the use of plant raw material ingredients in feeds for Atlantic salmon.

  19. Baltic Salmon, Salmo salar, from Swedish River Lule Älv Is More Resistant to Furunculosis Compared to Rainbow Trout

    DEFF Research Database (Denmark)

    Holten-Andersen, Lars; Dalsgaard, Inger; Buchmann, Kurt

    2012-01-01

    Background: Furunculosis, caused by Aeromonas salmonicida, continues to be a major health problem for the growing salmonid aquaculture. Despite effective vaccination programs regular outbreaks occur at the fish farms calling for repeated antibiotic treatment. We hypothesized that a difference...... in natural susceptibility to this disease might exist between Baltic salmon and the widely used rainbow trout. Study Design: A cohabitation challenge model was applied to investigate the relative susceptibility to infection with A. salmonicida in rainbow trout and Baltic salmon. The course of infection...

  20. Ontogeny of the Digestive System of Atlantic Salmon (Salmo salar L.) and Effects of Soybean Meal from Start-Feeding

    National Research Council Canada - National Science Library

    Sahlmann, Christian; Gu, Jinni; Kortner, Trond M; Lein, Ingrid; Krogdahl, Åshild; Bakke, Anne Marie

    2015-01-01

    .... In this study, we characterized the development of the gastrointestinal tract and accessory digestive organs for five months following hatch by using histological, biochemical and molecular methods...

  1. Identifying the source of farmed escaped Atlantic salmon (Salmo salar): Bayesian clustering analysis increases accuracy of assignment

    DEFF Research Database (Denmark)

    Glover, Kevin A.; Hansen, Michael Møller; Skaala, Oystein

    2009-01-01

    Farmed Atlantic salmon escapees represent a significant threat to the genetic integrity of natural populations. Not all escapement events are reported, and consequently, there is a need to develop an effective tool for the identification of escapees. In this study, > 2200 salmon were collected from...

  2. Genomewide single nucleotide polymorphism discovery in Atlantic salmon (Salmo salar): validation in wild and farmed American and European populations.

    Science.gov (United States)

    Yáñez, J M; Naswa, S; López, M E; Bassini, L; Correa, K; Gilbey, J; Bernatchez, L; Norris, A; Neira, R; Lhorente, J P; Schnable, P S; Newman, S; Mileham, A; Deeb, N; Di Genova, A; Maass, A

    2016-07-01

    A considerable number of single nucleotide polymorphisms (SNPs) are required to elucidate genotype-phenotype associations and determine the molecular basis of important traits. In this work, we carried out de novo SNP discovery accounting for both genome duplication and genetic variation from American and European salmon populations. A total of 9 736 473 nonredundant SNPs were identified across a set of 20 fish by whole-genome sequencing. After applying six bioinformatic filtering steps, 200 K SNPs were selected to develop an Affymetrix Axiom(®) myDesign Custom Array. This array was used to genotype 480 fish representing wild and farmed salmon from Europe, North America and Chile. A total of 159 099 (79.6%) SNPs were validated as high quality based on clustering properties. A total of 151 509 validated SNPs showed a unique position in the genome. When comparing these SNPs against 238 572 markers currently available in two other Atlantic salmon arrays, only 4.6% of the SNP overlapped with the panel developed in this study. This novel high-density SNP panel will be very useful for the dissection of economically and ecologically relevant traits, enhancing breeding programmes through genomic selection as well as supporting genetic studies in both wild and farmed populations of Atlantic salmon using high-resolution genomewide information. © 2016 John Wiley & Sons Ltd.

  3. Long-term epidemiological survey of Kudoa thyrsites (Myxozoa) in Atlantic salmon (Salmo salar L.) from commercial aquaculture farms.

    Science.gov (United States)

    Marshall, W L; Sitjà-Bobadilla, A; Brown, H M; MacWilliam, T; Richmond, Z; Lamson, H; Morrison, D B; Afonso, L O B

    2016-08-01

    Kudoa thyrsites (Myxozoa) encysts within myocytes of a variety of fishes. While infected fish appear unharmed, parasite-derived enzymes degrade the flesh post-mortem. In regions of British Columbia (BC), Canada, up to 4-7% of fillets can be affected, thus having economic consequences and impacting the competitiveness of BC's farms. K. thyrsites was monitored in two farms having high (HP) or low (LP) historical infection prevalence. At each farm, 30 fish were sampled monthly for blood and muscle during the first year followed by nine samplings during year two. Prevalence and intensity were measured by PCR and histology of muscle samples. In parallel, fillet tests were used to quantify myoliquefaction. Infections were detected by PCR after 355 and 509 degree days at LP and HP farms, respectively. Prevalence reached 100% at the HP farm by 2265 degree days and declined during the second year, whereas it plateaued near 50% at the LP farm. Infection intensities decreased after 1 year at both farms. Blood was PCR-positive at both farms between 778 and 1113 degree days and again after 2000 degree days. This is the first monitoring project in a production environment and compares data between farms with different prevalence. © 2015 John Wiley & Sons Ltd.

  4. Case definition for clinical and subclinical bacterial kidney disease (BKD) in Atlantic Salmon (Salmo salar L.) in New Brunswick, Canada.

    Science.gov (United States)

    Boerlage, A S; Stryhn, H; Sanchez, J; Hammell, K L

    2017-03-01

    Bacterial kidney disease (BKD) is considered an important cause of loss in salmon aquaculture in Atlantic Canada. Causative agent of BKD is the Gram-positive bacteria Renibacterium salmoninarum. Infected salmon are often asymptomatic (subclinical infection), and the disease is considered chronic. One of the challenges in quantifying information from farm production and health records is the application of a standardized case definition. Case definitions for farm-level and cage-level clinical and subclinical BKD were developed using retrospective longitudinal data from aquaculture practices in New Brunswick, Canada, combining (i) industry records of weekly production data including mortalities, (ii) field observations for BKD using reports of veterinarians and/or fish health technicians, (iii) diagnostic submissions and test results and (iv) treatments used to control BKD. Case definitions were evaluated using veterinarians' expert judgements as reference standard. Eighty-nine and 66% of sites and fish groups, respectively, were associated with BKD at least once. For BKD present (subclinical or clinical), sensitivity and specificity of the case definition were 75-100% varying between event, fish group, site cycle and level (site pen). For clinical BKD, sensitivities were 29-64% and specificities 91-100%. Industry data can be used to develop sensitive case definitions. © 2016 John Wiley & Sons Ltd.

  5. Potential disease interaction reinforced: double-virus-infected escaped farmed Atlantic salmon, Salmo salar L., recaptured in a nearby river.

    Science.gov (United States)

    Madhun, A S; Karlsbakk, E; Isachsen, C H; Omdal, L M; Eide Sørvik, A G; Skaala, Ø; Barlaup, B T; Glover, K A

    2015-02-01

    The role of escaped farmed salmon in spreading infectious agents from aquaculture to wild salmonid populations is largely unknown. This is a case study of potential disease interaction between escaped farmed and wild fish populations. In summer 2012, significant numbers of farmed Atlantic salmon were captured in the Hardangerfjord and in a local river. Genetic analyses of 59 of the escaped salmon and samples collected from six local salmon farms pointed out the most likely source farm, but two other farms had an overlapping genetic profile. The escapees were also analysed for three viruses that are prevalent in fish farming in Norway. Almost all the escaped salmon were infected with salmon alphavirus (SAV) and piscine reovirus (PRV). To use the infection profile to assist genetic methods in identifying the likely farm of origin, samples from the farms were also tested for these viruses. However, in the current case, all the three farms had an infection profile that was similar to that of the escapees. We have shown that double-virus-infected escaped salmon ascend a river close to the likely source farms, reinforcing the potential for spread of viruses to wild salmonids. © 2014 The Authors. Journal of Fish Diseases published by John Wiley & Sons Ltd.

  6. Toxicokinetic model assessment on the dechlorination of dietary toxaphene CHB-62 into CHB-44 in Atlantic salmon (Salmo salar L.).

    Science.gov (United States)

    Berntssen, M H G; Lock, E J; Zeilmaker, M J; Van Eijkeren, J C H

    2013-01-01

    European Union legislation on the upper limits of toxaphene in feed and food include the congeners CHB-26, CHB-62 and CHB-50 and is set at 50 µg kg⁻¹ feed for the sum of these three congeners. However, due to their elevated presence in fish, the congeners CHB-40 and CHB-41, CHB-44, and CHB-42 should also be included according to the European Food Safety Authority (EFSA) in 2005. Earlier trials with model zebra fish have shown in vivo dechlorination of dietary CHB-62 to CHB-44 and, to a lesser degree, of CHB-50 to CHB-40. Biomagnification patterns of Atlantic salmon, fed with technical toxaphene-enriched feeds, indicated that Atlantic salmon have a similar dechlorination. In the present study, a serial one-compartment physiological kinetic model, which includes differentiated growth of body components, is used to quantify the contribution of dechlorination to the congener-specific fillet accumulation of a mixture of dietary toxaphene congeners in Atlantic salmon. The model is assessed from experimental uptake and elimination kinetics of Atlantic salmon smolt fed with technical toxaphene for 122 days followed by a depuration period of 75 days in which the fish were fed toxaphene-free control feed. The serial one-compartment model shows that about 31% of CHB-44 that accumulated in the fillet originated from dietary CHB-62. In contrast, dechlorination of CHB-50 into CHB-40 is not significant. The results show that previously demonstrated in vivo dechlorination of CHB-62 into CHB-44 in zebra fish also occurs in the farmed fish species Atlantic salmon. This dechlorination can at least partly explain the relatively elevated CHB-44 observed in toxaphene fish surveys.

  7. Immune parameters in the intestine of wild and reared unvaccinated and vaccinated Atlantic salmon (Salmo salar L.).

    Science.gov (United States)

    Løkka, Guro; Austbø, Lars; Falk, Knut; Bromage, Erin; Fjelldal, Per Gunnar; Hansen, Tom; Hordvik, Ivar; Koppang, Erling Olaf

    2014-11-01

    Forming a barrier to the outside world, the gut mucosa faces the challenge of absorbing nutrients and fluids while initiating immune reactions towards potential pathogens. As a continuation to our previous publication focusing on the regional intestinal morphology in wild caught post smolt and spawning Atlantic salmon, we here investigate selected immune parameters and compare wild, reared unvaccinated and vaccinated post smolts. We observed highest transcript levels for most immune-related genes in vaccinated post smolts followed by reared unvaccinated and finally wild post smolts, indicating that farming conditions like commercial feed and vaccination might contribute to a more alerted immune system in the gut. In all groups, higher levels of immune transcripts were observed in the second segment of mid-intestine and in the posterior segment. In the life stages and conditions investigated here, we found no indication of a previously suggested population of intestinal T cells expressing MHC class II nor RAG1 expression. Copyright © 2014 Elsevier Ltd. All rights reserved.

  8. Detection of quantitative trait loci (QTL) related to grilsing and late sexual maturation in Atlantic salmon (Salmo salar).

    Science.gov (United States)

    Gutierrez, Alejandro P; Lubieniecki, Krzysztof P; Fukui, Steve; Withler, Ruth E; Swift, Bruce; Davidson, William S

    2014-02-01

    In Atlantic salmon aquaculture, early sexual maturation represents a major problem for producers. This is especially true for grilse, which mature after one sea winter before reaching a desirable harvest weight, rather than after two sea winters. Salmon maturing as grilse have a much lower market value than later maturing individuals. For this reason, most companies desire fish that grow fast and mature late. Marker-assisted selection has the potential to improve the efficiency of selection against early maturation and for late sexual maturation; however, studies identifying age of sexual maturation-related genetic markers are lacking for Atlantic salmon. Therefore, we used a 6.5K single-nucleotide polymorphism (SNP) array to genotype five families from the Mainstream Canada broodstock program and search for SNPs associated with early (grilsing) or late sexual maturation. There were 529 SNP loci that were variable across all five families, and this was the set that was used for quantitative trait loci (QTL) analysis. GridQTL identified two chromosomes, Ssa10 and Ssa21, containing QTL related to grilsing. In contrast, only one QTL, on Ssa18, was found linked to late maturation in Atlantic salmon. Our previous work on these five families did not identify genome-wide significant growth-related QTL on Ssa10, Ssa21, or Ssa18. Therefore, taken together, these results suggest that both grilsing and late sexual maturation are controlled independently of one another and also from growth-related traits. The identification of genomic regions associated with grilsing or late sexual maturation provide an opportunity to incorporate this information into selective breeding programs that will enhance Atlantic salmon farming.

  9. Marquage magnétique interne : essais de tolérance par de jeunes saumons atlantiques (Salmo salar L.

    Directory of Open Access Journals (Sweden)

    DUMAS J.

    1982-10-01

    Full Text Available Les effets de l'implantation d'une marque magnétique "Metalimphy" * de 20 x 1,5 mm dans la cavité abdominale de jeunes saumons d'élevage sont comparés à ceux d'un marquage classique par ablation de la nageoire adipeuse. Les essais sont effectués sur des tacons de deuxième été et des pré-saumoneaux d'un an dans deux piscicultures de Bretagne et des Pyrénées-Atlantiques. Quel que soit le mode d'insertion pratiqué (ventral ou latéral cette technique n'a aucun effet significatif sur la survie et la croissance des poissons, qu'ils soient tacons (observés sur 194 jours ou pré-saumoneaux (observés sur 56 jours. La cicatrisation est rapide et ce marquage n'entrave pas la smoltification. L'emploi d'une poudre antibiotique cicatrisante ne semble pas nécessaire en conditions normales de pisciculture. L'insertion par voie ventrale s'avère préférable à l'insertion latérale ; elle n'entraîne pas de pertes de marques et se révèle plus facile à pratiquer.

  10. Effects of 17{alpha}-ethynylestradiol on hormonal responses and xenobiotic biotransformation system of Atlantic salmon (Salmo salar)

    Energy Technology Data Exchange (ETDEWEB)

    Mortensen, Anne S. [Department of Biology, Norwegian University of Science and Technology (NTNU), Hogskoleringen 5, 7491 Trondheim (Norway); Arukwe, Augustine [Department of Biology, Norwegian University of Science and Technology (NTNU), Hogskoleringen 5, 7491 Trondheim (Norway)], E-mail: arukwe@bio.ntnu.no

    2007-11-30

    Pharmaceuticals are ubiquitous pollutants in the aquatic environment where their potential effects on non-target species like fish has only recently become subject of systematic investigations. In the present study, experiments were undertaken to examine the effects of a synthetic pharmaceutical endocrine disruptor, ethynylestradiol (EE2), given in water at 5 or 50 ng/L and sampled at days 0 (control), 3 and 7 after exposure, on hepatic phase I and II biotransformation and hormonal pathways of juvenile salmon using quantitative (real-time) polymerase chain reaction (qPCR), Vtg ELISA and 7-ethoxyresorufin O-deethylase (EROD) catalytic activity. Our data show that EE2 produced time- and concentration-specific modulation of estrogen receptor isoforms (ER{alpha}, ER{beta}) and androgen receptor-{beta} (AR{beta}). EE2 produced a concentration-specific induction of vitellogenin (Vtg) and zona radiata protein (Zr-protein) at day 3 after exposure. At day 7, Vtg and Zr-protein mRNA (and plasma Vtg protein) expression were significantly decreased in the group given 5 ng EE2/L, compared to dimethyl sulfoxide (DMSO) control group. In the xenobiotic biotransformation pathway, EE2 produced a significant increase of aryl hydrocarbon receptor-{alpha} (AhR{alpha}) at day 3 in the group given 5 ng EE2/L and AhR{beta} was decreased at the same concentration at day 7. While CYP3A was not significantly affected by EE2 exposure, the CYP1A1, AhR nuclear translocator (Arnt) and AhR repressor (AhRR) mRNA showed an apparent EE2 concentration and time-dependent decrease. The expression of uridine diphosphoglucuronosyl transferase (UGT) and glutathione S-transferase class pi-like (GSTpi-like) mRNA were decreased after exposure to 50 ng EE2/L at both day 3 and 7 after exposure. The effect of EE2 on the CYP1A1 gene expressions paralleled effect on EROD and AhRR mRNA, suggesting a direct role of EE2 in controlling cellular detoxification machinery. Interestingly, the carrier vehicle, DMSO produced significant time-dependent induction of estrogenic (ER{alpha}, Vtg and Zr-protein) responses, compared with blank (i.e. without DMSO) controls at day 7 post-exposure. The effect of DMSO totally underscored the observed EE2 effect at day 7 after exposure. In general, these findings support previous reports on the endocrine effects of EE2, in addition to effects on hepatic biotransformation system. In view of the data presented here and our recent studies, the use of DMSO as carrier vehicle in endocrine toxicological experimental studies should be re-evaluated.

  11. Dietary soyasaponin supplementation to pea protein concentrate reveals nutrigenomic interactions underlying enteropathy in Atlantic salmon (Salmo salar)

    OpenAIRE

    Kortner Trond M; Skugor Stanko; Penn Michael H; Mydland Liv; Djordjevic Brankica; Hillestad Marie; Krasnov Aleksei; Krogdahl Åshild

    2012-01-01

    Abstract Background Use of plant ingredients in aquaculture feeds is impeded by high contents of antinutritional factors such as saponins, which may cause various pharmacological and biological effects. In this study, transcriptome changes were analyzed using a 21 k oligonucleotide microarray and qPCR in the distal intestine of Atlantic salmon fed diets based on five plant protein sources combined with soybean saponins. Results Diets with corn gluten, sunflower, rapeseed or horsebean produced...

  12. Dietary soyasaponin supplementation to pea protein concentrate reveals nutrigenomic interactions underlying enteropathy in Atlantic salmon (Salmo salar).

    Science.gov (United States)

    Kortner, Trond M; Skugor, Stanko; Penn, Michael H; Mydland, Liv Torunn; Djordjevic, Brankica; Hillestad, Marie; Krasnov, Aleksei; Krogdahl, Åshild

    2012-07-02

    Use of plant ingredients in aquaculture feeds is impeded by high contents of antinutritional factors such as saponins, which may cause various pharmacological and biological effects. In this study, transcriptome changes were analyzed using a 21 k oligonucleotide microarray and qPCR in the distal intestine of Atlantic salmon fed diets based on five plant protein sources combined with soybean saponins. Diets with corn gluten, sunflower, rapeseed or horsebean produced minor effects while the combination of saponins with pea protein concentrate caused enteritis and major transcriptome changes. Acute inflammation was characterised by up-regulation of cytokines, NFkB and TNFalpha related genes and regulators of T-cell function, while the IFN-axis was suppressed. Induction of lectins, complement, metalloproteinases and the respiratory burst complex parallelled a down-regulation of genes for free radical scavengers and iron binding proteins. Marked down-regulation of xenobiotic metabolism was also observed, possibly increasing vulnerability of the intestinal tissue. A hallmark of metabolic changes was dramatic down-regulation of lipid, bile and steroid metabolism. Impairment of digestion was further suggested by expression changes of nutrient transporters and regulators of water balance (e.g. aquaporin, guanylin). On the other hand, microarray profiling revealed activation of multiple mucosal defence processes. Annexin-1, with important anti-inflammatory and gastroprotective properties, was markedly up-regulated. Furthermore, augmented synthesis of polyamines needed for cellular proliferation (up-regulation of arginase and ornithine decarboxylase) and increased mucus production (down-regulation of glycan turnover and goblet cell hyperplasia) could participate in mucosal healing and restoration of normal tissue function. The current study promoted understanding of salmon intestinal pathology and establishment of a model for feed induced enteritis. Multiple gene expression profiling further characterised the inflammation and described the intestinal pathology at the molecular level.

  13. Dietary soyasaponin supplementation to pea protein concentrate reveals nutrigenomic interactions underlying enteropathy in Atlantic salmon (Salmo salar

    Directory of Open Access Journals (Sweden)

    Kortner Trond M

    2012-07-01

    Full Text Available Abstract Background Use of plant ingredients in aquaculture feeds is impeded by high contents of antinutritional factors such as saponins, which may cause various pharmacological and biological effects. In this study, transcriptome changes were analyzed using a 21 k oligonucleotide microarray and qPCR in the distal intestine of Atlantic salmon fed diets based on five plant protein sources combined with soybean saponins. Results Diets with corn gluten, sunflower, rapeseed or horsebean produced minor effects while the combination of saponins with pea protein concentrate caused enteritis and major transcriptome changes. Acute inflammation was characterised by up-regulation of cytokines, NFkB and TNFalpha related genes and regulators of T-cell function, while the IFN-axis was suppressed. Induction of lectins, complement, metalloproteinases and the respiratory burst complex parallelled a down-regulation of genes for free radical scavengers and iron binding proteins. Marked down-regulation of xenobiotic metabolism was also observed, possibly increasing vulnerability of the intestinal tissue. A hallmark of metabolic changes was dramatic down-regulation of lipid, bile and steroid metabolism. Impairment of digestion was further suggested by expression changes of nutrient transporters and regulators of water balance (e.g. aquaporin, guanylin. On the other hand, microarray profiling revealed activation of multiple mucosal defence processes. Annexin-1, with important anti-inflammatory and gastroprotective properties, was markedly up-regulated. Furthermore, augmented synthesis of polyamines needed for cellular proliferation (up-regulation of arginase and ornithine decarboxylase and increased mucus production (down-regulation of glycan turnover and goblet cell hyperplasia could participate in mucosal healing and restoration of normal tissue function. Conclusion The current study promoted understanding of salmon intestinal pathology and establishment of a model for feed induced enteritis. Multiple gene expression profiling further characterised the inflammation and described the intestinal pathology at the molecular level. Ethical approval The present experiment was approved by the Norwegian Animal Research Authority and conducted according to prevailing animal welfare regulations: FOR-1996-01-15-23 (Norway, European Convention for the Protection of Vertebrate Animals used for Experimental and Other Scientific Purposes (Strasbourg, 18.III.1986 and COUNCIL DIRECTIVE of 24 November 1986 on the approximation of laws, regulations and administrative provisions of the Member States regarding the protection of animals used for experimental and other scientific purposes (86/609/EEC.

  14. Fatty acids, mercury, and methylmercury bioaccessibility in salmon (Salmo salar) using an in vitro model: Effect of culinary treatment.

    Science.gov (United States)

    Costa, Sara; Afonso, Cláudia; Cardoso, Carlos; Batista, Irineu; Chaveiro, Nádia; Nunes, Maria Leonor; Bandarra, Narcisa Maria

    2015-10-15

    The effect of culinary treatments on the fatty acid profile, mercury (Hg), and methylmercury (MeHg) levels of salmon was studied. The bioaccessibility of fatty acids, Hg, and MeHg in raw and grilled salmon was determined. The most intense thermal treatment (grilling) did not alter the relative fatty acid (FA) profile. There were bioaccessibility differences between FAs. To the authors' knowledge, for the first time, higher bioaccessibility of the long-chain FAs than the short- and medium-chain FAs was measured. Chemical interaction phenomena seemed to play a role. On the other hand, higher levels of unsaturation decreased bioaccessibility. Two main alternative hypotheses were put forward, either lower polarity led to higher incorporation of FAs with longer hydrophobic aliphatic chain and lower number of double bonds in the emulsion present in the bioaccessible fraction or enzymatic selectivity preferentially hydrolyzed some FAs on the basis of their structure or position in the triacylglycerol molecule. Copyright © 2015 Elsevier Ltd. All rights reserved.

  15. The vgll3 Locus Controls Age at Maturity in Wild and Domesticated Atlantic Salmon (Salmo salar L. Males.

    Directory of Open Access Journals (Sweden)

    Fernando Ayllon

    2015-11-01

    Full Text Available Wild and domesticated Atlantic salmon males display large variation for sea age at sexual maturation, which varies between 1-5 years. Previous studies have uncovered a genetic predisposition for variation of age at maturity with moderate heritability, thus suggesting a polygenic or complex nature of this trait. The aim of this study was to identify associated genetic loci, genes and ultimately specific sequence variants conferring sea age at maturity in salmon. We performed a genome wide association study (GWAS using a pool sequencing approach (20 individuals per river and phenotype of male salmon returning to rivers as sexually mature either after one sea winter (2009 or three sea winters (2011 in six rivers in Norway. The study revealed one major selective sweep, which covered 76 significant SNPs in which 74 were found in a 370 kb region of chromosome 25. Genotyping other smolt year classes of wild and domesticated salmon confirmed this finding. Genotyping domesticated fish narrowed the haplotype region to four SNPs covering 2386 bp, containing the vgll3 gene, including two missense mutations explaining 33-36% phenotypic variation. A single locus was found to have a highly significant role in governing sea age at maturation in this species. The SNPs identified may be both used as markers to guide breeding for late maturity in salmon aquaculture and in monitoring programs of wild salmon. Interestingly, a SNP in proximity of the VGLL3 gene in humans (Homo sapiens, has previously been linked to age at puberty suggesting a conserved mechanism for timing of puberty in vertebrates.

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

    Energy Technology Data Exchange (ETDEWEB)

    McCormick, S.D.; Monette, M.Y. [United States Geological Survey, Turners Falls, MA (United States). Conte Anadromous Fish Research Center; Massachusetts Univ., Amherst, MA (United States). Organismic and Evolutionary Biology Program; Keyes, A. [United States Geological Survey, Turners Falls, MA (United States). Conte Anadromous Fish Research Center; Nislow, K.H. [Massachusetts Univ., Amherst, MA (United States). Organismic and Evolutionary Biology Program; United States Dept. of Agriculture, Amherst, MA (United States). Northern Research Station

    2009-02-20

    Episodic acidification is negatively impacting the conservation and recovery of Atlantic salmon in the northeastern United States. This article described a set of field studies conducted to determine the impacts of acid and aluminium (Al) levels on the survival, smolt development, ion homeostasis, and stress in Atlantic salmon smolts located in Connecticut River restoration streams in Vermont. The fish were observed in cages in 5 separate streams that encompassed a range of different acid and Al levels for two 6-day intervals at the peak of smolt development. The study showed that physiological parameters remained unchanged for smolts located in the high water quality reference site. However, mortality, loss of plasma chloride, and gill Na{sup +}/K{sup +}-ATPase activity, and elevated gill Al occurred at the sites with the highest levels of inorganic Al and the lowest pH levels. Losses of plasma chloride, moderately elevated gill Al, and increased plasma cortisol and glucose levels occurred at less severely impacted sites. The study also demonstrated that gill Al was a more accurate predictor of integrated physiological impacts than water chemistry. It was concluded that Al and low pH can cause mortality and impair smolt development in juvenile Atlantic salmon. 36 refs., 2 tabs., 4 figs.

  17. Trade-off between resource allocation and acquisition in anadromous adult male Atlantic salmon (Salmo salar L.

    Directory of Open Access Journals (Sweden)

    Tomislav Vladic

    2014-06-01

    Full Text Available Individual energetic limitations in variable environments lead to life-history trade-offs between investment in somatic growth and gonadal tissue, causing individuals to adopt specific behavioural tactics to attain reproduction. We investigated energy allocation in primary and secondary sexual traits in Atlantic salmon by estimating the life history characters (smolt size, sea age, first sea year growth rate by back-calculation of scales. Adult size increased with the fish sea age (years at sea and exerted a strong allometric effect on the energy investment pattern into secondary sexual traits. A compensatory mechanism at the ejaculate level is identified by which males investing less in secondary sexual traits produce ejaculates of higher quality. Distinct differences in investment into primary and secondary sexual traits between the fish that spent a single year in the sea before returning to the spawn (grilse and multi-sea-year adults were detected, indicating that their energy allocation strategy in reproductive effort reflects alternative developmental pathways. Grilse ejaculate investment depended more on the resource allocation, whereas multi-sea-year male ejaculate investment depended more on the resource acquisition.

  18. Evaluation of the spoilage potential of bacteria isolated from spoiled raw salmon (Salmo salar) fillets stored under modified atmosphere packaging.

    Science.gov (United States)

    Macé, Sabrina; Joffraud, Jean-Jacques; Cardinal, Mireille; Malcheva, Mariya; Cornet, Josiane; Lalanne, Valérie; Chevalier, Frédérique; Sérot, Thierry; Pilet, Marie-France; Dousset, Xavier

    2013-01-01

    The spoilage potential of eight bacterial groups/species (Serratia spp., Hafnia alvei, Brochothrix thermosphacta, Carnobacterium maltaromaticum, Shewanella baltica, Lactococcus piscium, Photobacterium phosphoreum, "other Enterobacteriaceae" [containing one strain of Moellerella sp., Morganella sp. and Pectobacterium sp.]) isolated from spoiled raw salmon fillets stored under modified atmosphere packaging (MAP) was evaluated by inoculation into sterile raw salmon cubes followed by storage for 12days at 8°C. Microbial growth and sensory changes were monitored during the storage period. The dominant spoilage bacteria were C. maltaromaticum, H. alvei and P. phosphoreum. In order to further characterize their spoilage potential and to study the effect of their interactions, each of these 3 specific spoilage organisms (SSO) and two mixed-cultures, C. maltaromaticum/H. alvei and C. maltaromaticum/P. phosphoreum were tested in the sterile salmon model system using a combination of complementary methods: molecular (PCR-TTGE), sensory, chemical and conventional microbiological analyses. It was concluded that, in the mixed-culture inoculated samples, the dominant species determined the spoilage characteristics. The volatile fraction of P. phosphoreum inoculated samples was analyzed by solid-phase microextraction (SPME) followed by gas chromatography coupled to mass spectrometry (GC-MS). Among the specific volatile compounds present on P. phosphoreum spoiled inoculated samples, acetic acid was correlated with sensory analysis and can be proposed as a raw salmon spoilage marker. Copyright © 2012 Elsevier B.V. All rights reserved.

  19. Ontogeny of the Digestive System of Atlantic Salmon (Salmo salar L.) and Effects of Soybean Meal from Start-Feeding

    Science.gov (United States)

    Sahlmann, Christian; Gu, Jinni; Kortner, Trond M.; Lein, Ingrid; Krogdahl, Åshild; Bakke, Anne Marie

    2015-01-01

    Despite a long history of rearing Atlantic salmon in hatcheries in Norway, knowledge of molecular and physiological aspects of juvenile development is still limited. To facilitate introduction of alternative feed ingredients and feed additives during early phases, increased knowledge regarding the ontogeny of the digestive apparatus in salmon is needed. In this study, we characterized the development of the gastrointestinal tract and accessory digestive organs for five months following hatch by using histological, biochemical and molecular methods. Furthermore, the effects of a diet containing 16.7% soybean meal (SBM) introduced at start-feeding were investigated, as compared to a fishmeal based control diet. Salmon yolk sac alevins and fry were sampled at 18 time points from hatch until 144 days post hatch (dph). Histomorphological development was investigated at 7, 27, 46, 54 and 144 dph. Ontogenetic expression patterns of genes encoding key digestive enzymes, nutrient transporters, gastrointestinal peptide hormones and T-cell markers were analyzed from 13 time points by qPCR. At 7 dph, the digestive system of Atlantic salmon alevins was morphologically distinct with an early stomach, liver, pancreas, anterior and posterior intestine. About one week before the yolk sac was internalized and exogenous feeding was started, gastric glands and developing pyloric caeca were observed, which coincided with an increase in gene expression of gastric and pancreatic enzymes and nutrient transporters. Thus, the observed organs seemed ready to digest external feed well before the yolk sac was absorbed into the abdominal cavity. In contrast to post-smolt Atlantic salmon, inclusion of SBM did not induce intestinal inflammation in the juveniles. This indicates that SBM can be used in compound feeds for salmon fry from start-feeding to at least 144 dph and/or 4-5 g body weight. PMID:25923375

  20. Estrogenic effects of selected hydroxy polychlorinated biphenyl congeners in primary culture of Atlantic Salmon (Salmo salar) hepatocytes.

    Science.gov (United States)

    Braathen, Marte; Mortensen, Anne Skjetne; Sandvik, Morten; Skåre, Janneche Utne; Arukwe, Augustine

    2009-01-01

    Many persistent organic pollutants are known to have endocrine-disrupting effects in several aquatic and terrestrial species. In this regard, hydroxylated metabolites of polychlorinated biphenyls (OH-PCBs) represent serious health and environmental concern because they are shown to act agonistic or antagonistic at hormone receptors (HRs) or to cause hormone-receptor-mediated responses. In the present study, salmon primary hepatocytes were used to study alterations in an estrogen signaling pathway resulting from exposure to four hydroxylated (4OH-CB 107, 4OH-CB146, 4OH-CB187, and 3OH-CB138) metabolites of PCB at different concentrations using quantitative real-time polymerase chain reaction. The effects of the PCB metabolites were compared to the mRNA expression in 17alpha-ethynylestradiol (EE2)-treated cells. Concentration-specific increase of vitellogenin (Vtg) mRNA transcription after exposure to OH-PCBs was observed. Decreased mRNA transcription was observed for zona radiata protein (Zr-protein) and cytochrome P450 side-chain cleavage (P450scc) enzyme. For estrogen receptor beta (ERbeta), the mRNA expression pattern was OH-PCB-metabolite congener-specific. A novel aspect of this study is that OH-PCBs produced effects on hepatic steroidogenic pathways by targeting the StAR protein and P450scc genes. Given that endocrine toxicology research mainly has focused on estrogenicity involving direct ER-mediated effects and that steroidogenic enzyme and proteins are highly tissue- and cell-type-specific and controlled by different promoters and second-messenger pathways, the present findings provide potential new targets for interaction with xenobiotics such as hydroxylated congeners of certain chemicals. The quantitative expression patterns of hepatic and extrahepatic steroidogenic genes and proteins after exposure to environmental contaminants are the subject of systematic investigations in our laboratory.

  1. A procedure for disinfecting Atlantic salmon (Salmo salar) eggs using a polyvinylpyrrolidone-iodine (PVP-I) solution

    National Research Council Canada - National Science Library

    Frantsi, C; Withey, K.G

    1972-01-01

    .... The procedure involves complete disinfection of incubation facilities, hardening, measuring, picking of dead eggs, and disinfection of eggs for 10 minutes in a solution of polyvinylpyrrolidone-iodine (PVP...

  2. Effect of pancreas disease (PD) on quality attributes of raw and smoked fillets of Atlantic salmon (Salmo salar L.)

    DEFF Research Database (Denmark)

    Lerfall, Jørgen; Larsson, Thomas; Birkeland, Sveinung

    2012-01-01

    The impact of pancreas disease (PD) on fillet quality of raw and cold-smoked Atlantic salmon was investigated. Commercially reared fish were sorted into six groups: (1) Control (healthy fish), (2) SAV (infection with salmonid alphavirus, without PD outbreak), (3) PD0 (PD diagnosis at slaughter), (4...

  3. Baltic Salmon, Salmo salar, from Swedish River Lule Älv Is More Resistant to Furunculosis Compared to Rainbow Trout

    Science.gov (United States)

    Holten-Andersen, Lars; Dalsgaard, Inger; Buchmann, Kurt

    2012-01-01

    Background Furunculosis, caused by Aeromonas salmonicida, continues to be a major health problem for the growing salmonid aquaculture. Despite effective vaccination programs regular outbreaks occur at the fish farms calling for repeated antibiotic treatment. We hypothesized that a difference in natural susceptibility to this disease might exist between Baltic salmon and the widely used rainbow trout. Study Design A cohabitation challenge model was applied to investigate the relative susceptibility to infection with A. salmonicida in rainbow trout and Baltic salmon. The course of infection was monitored daily over a 30-day period post challenge and the results were summarized in mortality curves. Results A. salmonicida was recovered from mortalities during the entire test period. At day 30 the survival was 6.2% and 34.0% for rainbow trout and Baltic salmon, respectively. Significant differences in susceptibility to A. salmonicida were demonstrated between the two salmonids and hazard ratio estimation between rainbow trout and Baltic salmon showed a 3.36 higher risk of dying from the infection in the former. Conclusion The finding that Baltic salmon carries a high level of natural resistance to furunculosis might raise new possibilities for salmonid aquaculture in terms of minimizing disease outbreaks and the use of antibiotics. PMID:22276121

  4. Preliminary success using hydrogen peroxide to treat Atlantic salmon, Salmo salar L., affected with experimentally induced amoebic gill disease (AGD).

    Science.gov (United States)

    Adams, M B; Crosbie, P B B; Nowak, B F

    2012-11-01

    Currently, the only effective and commercially used treatment for amoebic gill disease (AGD) in farmed Tasmanian Atlantic salmon is freshwater bathing. Hydrogen peroxide (H₂O₂), commonly used throughout the aquaculture industry for a range of topical skin and gill infections, was trialled in vitro and in vivo to ascertain its potential as an alternative treatment against AGD. Under in vitro conditions, trophozoites of Neoparamoeba perurans were exposed to three concentrations of H₂O₂ in sea water (500, 1000 and 1500 mg L⁻¹) over four durations (10, 20, 30 and 60 min) each at two temperatures (12 and 18 °C). Trophozoite viability was assessed immediately post-exposure and after 24 h. A concentration/duration combination of 1000 mg L⁻¹ for >10 min demonstrated potent amoebicidal activity. Subsequently, Atlantic salmon mildly affected with experimentally induced AGD were treated with H₂O₂ at 12 and 18 °C for 15 min at 1250 mg L⁻¹ and their re-infection rate was compared to freshwater-treated fish over 21 days. Significant differences in the percentage of filaments affected with hyperplastic lesions (in association with amoebae) and plasma osmolality were noted between treatment groups immediately post-bath. However, the results were largely equivocal in terms of disease resolution over a 3-week period following treatment. These data suggest that H₂O₂ treatment in sea water successfully ameliorated a clinically light case of AGD under laboratory conditions. © 2012 Blackwell Publishing Ltd.

  5. Stochastic modelling of direct costs of pancreas disease (PD) in Norwegian farmed Atlantic salmon (Salmo salar L.).

    Science.gov (United States)

    Aunsmo, Arnfinn; Valle, Paul Steinar; Sandberg, Marianne; Midtlyng, Paul Johan; Bruheim, Torkjel

    2010-02-01

    An economic model for estimating the direct costs of disease in industrial aquaculture was developed to include the following areas: biological losses, extraordinary costs, costs of treatment, costs of prevention and insurance pay-out. Direct costs of a pancreas disease (PD) outbreak in Norwegian farmed Atlantic salmon were estimated in the model, using probability distributions for the biological losses and expenditures associated with the disease. The biological effects of PD on mortality, growth, feed conversion and carcass quality and their correlations, together with costs of prevention were established using elicited data from an expert panel, and combined with basal losses in a control model. Extraordinary costs and costs associated with treatment were collected through a questionnaire sent to staff managing disease outbreaks. Norwegian national statistics for 2007 were used for prices and production costs in the model. Direct costs associated with a PD-outbreak in a site stocked with 500,000 smolts (vs. a similar site without the disease) were estimated to NOK (Norwegian kroner) 14.4 million (5% and 95% percentile: 10.5 and 17.8) (NOK=euro0.12 or $0.17 for 2007). Production was reduced to 70% (5% and 95% percentile: 57% and 81%) saleable biomass, and at an increased production cost of NOK 6.0 per kg (5% and 95% percentile: 3.5 and 8.7). Copyright 2009 Elsevier B.V. All rights reserved.

  6. Local and systemic gene expression responses of Atlantic salmon (Salmo salar L. to infection with the salmon louse (Lepeophtheirus salmonis

    Directory of Open Access Journals (Sweden)

    Nilsen Frank

    2008-10-01

    Full Text Available Abstract Background The salmon louse (SL is an ectoparasitic caligid crustacean infecting salmonid fishes in the marine environment. SL represents one of the major challenges for farming of salmonids, and veterinary intervention is necessary to combat infection. This study addressed gene expression responses of Atlantic salmon infected with SL, which may account for its high susceptibility. Results The effects of SL infection on gene expression in Atlantic salmon were studied throughout the infection period from copepodids at 3 days post infection (dpi to adult lice (33 dpi. Gene expression was analyzed at three developmental stages in damaged and intact skin, spleen, head kidney and liver, using real-time qPCR and a salmonid cDNA microarray (SFA2. Rapid detection of parasites was indicated by the up-regulation of immunoglobulins in the spleen and head kidney and IL-1 receptor type 1, CD4, beta-2-microglobulin, IL-12β, CD8α and arginase 1 in the intact skin of infected fish. Most immune responses decreased at 22 dpi, however, a second activation was observed at 33 dpi. The observed pattern of gene expression in damaged skin suggested the development of inflammation with signs of Th2-like responses. Involvement of T cells in responses to SL was witnessed with up-regulation of CD4, CD8α and programmed death ligand 1. Signs of hyporesponsive immune cells were seen. Cellular stress was prevalent in damaged skin as seen by highly significant up-regulation of heat shock proteins, other chaperones and mitochondrial proteins. Induction of the major components of extracellular matrix, TGF-β and IL-10 was observed only at the adult stage of SL. Taken together with up-regulation of matrix metalloproteinases (MMP, this classifies the wounds afflicted by SL as chronic. Overall, the gene expression changes suggest a combination of chronic stress, impaired healing and immunomodulation. Steady increase of MMP expression in all tissues except liver was a remarkable feature of SL infected fish. Conclusion SL infection in Atlantic salmon is associated with a rapid induction of mixed inflammatory responses, followed by a period of hyporesponsiveness and delayed healing of injuries. Persistent infection may lead to compromised host immunity and tissue self-destruction.

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

    Science.gov (United States)

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

    2013-02-01

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

  8. Effects of dietary thia fatty acids on lipid composition, morphology and macrophage function of Atlantic salmon (Salmo salar L.) kidney.

    Science.gov (United States)

    Gjøen, Tor; Kleveland, Ellen Johanne; Moya-Falcón, Corina; Frøystad, Marianne K; Vegusdal, Anne; Hvattum, Erlend; Berge, Rolf K; Ruyter, Bente

    2007-09-01

    High lipid levels are being used in modern salmonid diets to promote rapid growth; however there is a limiting supply of the traditional fish oils as the fish farming industry expands. One way to utilize the lipid sources better, could be to find ways to stimulate fatty acid (FA) oxidation so that Atlantic salmon use more energy for muscle growth and less for storage in perivisceral adipose tissue. We have previously shown that dietary inclusion of the thia FA tetradecylthioacetic acid (TTA) promoted hepatic beta-oxidation and reduced total body lipid levels. However, dietary TTA also had some negative effects, leading to accumulation of sulfone and sulfoxide metabolites of TTA in the kidney and increasing mortality rates, particularly at low water temperatures. Therefore we also wish to investigate the effects of TTA on kidney function at high and low temperatures, including some immune system parameters. The production of leukotriene B4 (LTB4) and prostaglandin E2 (PGE2) immunoreactive material from exogenously added arachidonic acid in isolated head kidney macrophages was affected by both diet and temperature. The phagocytic activity in these cells was reduced by DTA in the 12 degrees C group and there was significantly higher protein degradation in head kidney macrophages at 12 degrees C compared to 5 degrees C in all dietary groups. Interestingly, the incorporation of thia FAs in the kidney was higher at 5 degrees C (0.3% TTA and 0.6% DTA) than at 12 degrees C (0.1% TTA and 0.5% DTA). Additionally, there were lower levels of saturated FAs, while higher levels of polyunsaturated FAs (PUFAs) in the kidney of TTA fed fish at 5 degrees C. We also observed temperature-independent tubular dilatation and a reduction in the density of melanomacrophages of the kidney in salmon fed TTA. Nevertheless, the mRNA expression of some immune-relevant genes in head kidney tissue was not affected by TTA-inclusion in salmon diets. In conclusion, it is clear that 0.6% TTA-inclusion in the feed leads to changes in the kidney function particularly at low water temperatures.

  9. Local and systemic gene expression responses of Atlantic salmon (Salmo salar L.) to infection with the salmon louse (Lepeophtheirus salmonis).

    Science.gov (United States)

    Skugor, Stanko; Glover, Kevin Alan; Nilsen, Frank; Krasnov, Aleksei

    2008-10-23

    The salmon louse (SL) is an ectoparasitic caligid crustacean infecting salmonid fishes in the marine environment. SL represents one of the major challenges for farming of salmonids, and veterinary intervention is necessary to combat infection. This study addressed gene expression responses of Atlantic salmon infected with SL, which may account for its high susceptibility. The effects of SL infection on gene expression in Atlantic salmon were studied throughout the infection period from copepodids at 3 days post infection (dpi) to adult lice (33 dpi). Gene expression was analyzed at three developmental stages in damaged and intact skin, spleen, head kidney and liver, using real-time qPCR and a salmonid cDNA microarray (SFA2). Rapid detection of parasites was indicated by the up-regulation of immunoglobulins in the spleen and head kidney and IL-1 receptor type 1, CD4, beta-2-microglobulin, IL-12beta, CD8alpha and arginase 1 in the intact skin of infected fish. Most immune responses decreased at 22 dpi, however, a second activation was observed at 33 dpi. The observed pattern of gene expression in damaged skin suggested the development of inflammation with signs of Th2-like responses. Involvement of T cells in responses to SL was witnessed with up-regulation of CD4, CD8alpha and programmed death ligand 1. Signs of hyporesponsive immune cells were seen. Cellular stress was prevalent in damaged skin as seen by highly significant up-regulation of heat shock proteins, other chaperones and mitochondrial proteins. Induction of the major components of extracellular matrix, TGF-beta and IL-10 was observed only at the adult stage of SL. Taken together with up-regulation of matrix metalloproteinases (MMP), this classifies the wounds afflicted by SL as chronic. Overall, the gene expression changes suggest a combination of chronic stress, impaired healing and immunomodulation. Steady increase of MMP expression in all tissues except liver was a remarkable feature of SL infected fish. SL infection in Atlantic salmon is associated with a rapid induction of mixed inflammatory responses, followed by a period of hyporesponsiveness and delayed healing of injuries. Persistent infection may lead to compromised host immunity and tissue self-destruction.

  10. Accumulation and depuration of the synthetic antioxidant ethoxyquin in the muscle of Atlantic salmon (Salmo salar L.).

    Science.gov (United States)

    Bohne, Victoria J Berdikova; Lundebye, Anne-Katrine; Hamre, Kristin

    2008-05-01

    The biological fate of the fish feed additive, ethoxyquin (EQ) was examined in the muscle of Atlantic salmon during 12 weeks of feeding followed by a 2 weeks depuration period. Parent EQ (1,2-dihydro-6-ethoxy-2,2,4-trimethylquinoline), quinone imine (2,6-dihydro-2,2,4-trimethyl-6-quinolone), de-ethylated EQ (6-hydroxy-2,2,4-trimethyl-1,2-dihydroquinoline) and EQDM (EQ dimer or 1,8'-di(1,2-dihydro-6-ethoxy-2,2,4-trimethyl-quinoline) were found to be the ubiquitous metabolites of dietary EQ, with EQDM as a main metabolite. A rapid decrease in the level of EQ (2.4 days of half-life) was balanced by an increase in EQDM, giving an unchanged net sum following 2 weeks of depuration. The mandatory 14 days depuration period prior to slaughtering of farmed salmon in Norway was not sufficient for complete elimination of EQ-derived residuals. Post depuration, EQDM accounted for 99% of sum of the two compounds in all treatment groups; possible toxicological effects of EQDM are not known. The individual concentrations of EQ and EQDM and their sum are dependent on EQ level in the feed, consequently, their residual concentrations may be controlled. The theoretical amount of EQ and EQDM consumed in one meal of farmed salmon would be under the recommended ADI, provided that the fish were raised on feed with no more than 150 mg EQ/kg feed, which is the EU maximum limit for EQ in fish feed.

  11. Histological, digestive, metabolic, hormonal and some immune factor responses in Atlantic salmon, Salmo salar L., fed genetically modified soybeans.

    Science.gov (United States)

    Bakke-McKellep, A M; Koppang, E O; Gunnes, G; Sanden, M; Hemre, G-I; Landsverk, T; Krogdahl, A

    2007-02-01

    The paper reports the second and final part of an experiment aiming to study physiological and health-related effects of genetically modified (GM) soybean meal (SBM) type Roundup Ready soybean (RRS) in diets for post-smolt Atlantic salmon. For 3 months salmon were fed diets containing 172 g kg(-1) full-fat SBM from RRS (GM-soy) or an unmodified, non-isogenic line (nGM-soy), or a reference diet with fishmeal as the sole protein source (FM). Slight differences in anti-nutrient levels were observed between the GM and nGM-soy. Histological changes were observed only in the distal intestine of the soy-fed fish. The incidence of moderate inflammation was higher in the GM-soy group (9 of 10 sampled fish) compared with the nGM-soy group (7 of 10). However, no differences in the concomitant decreases in activities of digestive enzymes located in the brush border (leucine aminopeptidase and maltase) and apical cytoplasm (acid phosphatase) of enterocytes or in the number of major histocompatibility complex class II+ cells, lysozyme activity, or total IgM of the distal intestine were observed. GM compared with nGM-soy fed fish had higher head kidney lysozyme (11,856 vs. 10,456 units g(-1) tissue) and a tendency towards higher acid phosphatase (0.45 vs. 0.39 micromol h(-1) kg(-1) body mass in whole tissue) activities, respectively. Plasma insulin and thyroxin levels, and hepatic fructose-1,6-bisphosphatase and ethoxyresorufin-O-deethylase activities were not significantly affected. It is not possible, however, to conclude whether the differences in responses to GM-soy were due to the genetic modification or to differences in soy cultivars in the soy-containing diets. Results from studies using non-modified, parental line soybeans as the control group are necessary to evaluate whether genetic modification of soybeans in diets poses any risk to farmed Atlantic salmon.

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

    DEFF Research Database (Denmark)

    Vindas, Marco A; Sørensen, Christina; Johansen, Ida

    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....... 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...

  13. Variation in commercial sources of soybean meal influences the severity of enteritis in Atlantic salmon (Salmo salar L.)

    NARCIS (Netherlands)

    Urán, P.; Schrama, J.W.; Jaafari, S.; Baardsen, G.; Rombout, J.H.W.M.; Koppe, W.; Verreth, J.A.J.

    2009-01-01

    Soybean meal (SBM) is a potential alternative for the replacement of fishmeal in aquafeeds. In Atlantic salmon, however, dietary SBM causes an inflammation of the distal intestine, known as SBM-induced enteritis. The objective of the present study is to verify whether different (geographically

  14. Does implied volatility of currency futures option imply volatility of exchange rates?

    Science.gov (United States)

    Wang, Alan T.

    2007-02-01

    By investigating currency futures options, this paper provides an alternative economic implication for the result reported by Stein [Overreactions in the options market, Journal of Finance 44 (1989) 1011-1023] that long-maturity options tend to overreact to changes in the implied volatility of short-maturity options. When a GARCH process is assumed for exchange rates, a continuous-time relationship is developed. We provide evidence that implied volatilities may not be the simple average of future expected volatilities. By comparing the term-structure relationship of implied volatilities with the process of the underlying exchange rates, we find that long-maturity options are more consistent with the exchange rates process. In sum, short-maturity options overreact to the dynamics of underlying assets rather than long-maturity options overreacting to short-maturity options.

  15. 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

  16. 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.

  17. Option Implied Risk-Neutral Distributions and Implied Binomial Trees: A Literature Review

    OpenAIRE

    Jackwerth, Jens Carsten

    1999-01-01

    In this selective literature review, we start by observing that in efficient markets, there is information incorporated in option prices that might help us to design option pricing models. To this end, we review the numerous methods of recovering risk-neutral probability distributions from option prices at one particular time to expiration and their applications. Next, we move beyond one time to expiration to the construction of implied binomial trees, which model t...

  18. 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

  19. The impact of firm specific news on implied volatilities

    NARCIS (Netherlands)

    M.W.M. Donders (Monique); A.C.F. Vorst (Ton)

    1996-01-01

    textabstractWe study the implied volatility behavior of call options around scheduled news announcement days. Implied volatilities increase significantly during the pre-event period and reach a maximum on the eve of the news announcement. After the news release, implied volatility drops sharply and

  20. The impact of firm specific news on implied volatilities

    OpenAIRE

    Donders, Monique; Vorst, Ton

    1996-01-01

    textabstractWe study the implied volatility behavior of call options around scheduled news announcement days. Implied volatilities increase significantly during the pre-event period and reach a maximum on the eve of the news announcement. After the news release, implied volatility drops sharply and gradually moves back to its long-run level. Only on the event date are movements in the price of the underlying significantly larger than expected. These results confirm the theoretical results of ...

  1. 16 CFR 303.18 - Terms implying fibers not present.

    Science.gov (United States)

    2010-01-01

    ... 16 Commercial Practices 1 2010-01-01 2010-01-01 false Terms implying fibers not present. 303.18... RULES AND REGULATIONS UNDER THE TEXTILE FIBER PRODUCTS IDENTIFICATION ACT § 303.18 Terms implying fibers... designation of a fiber which is not present in the product, (b) which are phonetically similar to the name or...

  2. SALMO-PRIEST WILDERNESS STUDY AREA, WASHINGTON AND IDAHO.

    Science.gov (United States)

    Miller, F.K.; Schmauch, S.W.

    1984-01-01

    Geologic, geochemical, geophysical and mines and prospects evaluation of the Salmo-Priest Wilderness study area in Washington has yielded no evidence of significant mineral-resource potential. Although gold was detected in trace amounts to moderate anomalies in scattered stream-sediment concentrates it has probably been derived from small and localized occurrences and does not constitute a resource. As a result of this study the area appears to have little promise for the occurrence of metallic mineral resources, energy minerals, fossil fuels, and geothermal resources. Nonmetallic mineral resources, notably shale, are abundant, but adequate supplies exist outside the study area.

  3. Meritaimenen (Salmo Trutta M. Trutta) radiotelemetriaseuranta Tenojoessa 2011-2012

    OpenAIRE

    Leinonen, Velimatti

    2013-01-01

    Tämän opinnäytetyön tavoitteena on selvittää meritaimenen vaelluskäyttäytyminen ja taimenien levittäytyminen Tenojoen vesistössä. Opinnäytetyössä tarkastellaan Tenojoen vesistössä vuonna 2011 radiotelemetrialähettimin merkittyjen taimenten (Salmo trutta) liikkeitä. Opinnäytetyö liittyy Riista- ja kalatalouden tutkimuslaitoksen hankkeeseen ”Voisiko Tenojoen kalastuskautta pidentää? Meritaimenen biologia ja taimenkantojen hyödyntämismahdollisuudet”. Tutkimusalueena oli koko Tenojoen ves...

  4. 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.

  5. Implied preference for seismic design level and earthquake insurance.

    Science.gov (United States)

    Goda, K; Hong, H P

    2008-04-01

    Seismic risk can be reduced by implementing newly developed seismic provisions in design codes. Furthermore, financial protection or enhanced utility and happiness for stakeholders could be gained through the purchase of earthquake insurance. If this is not so, there would be no market for such insurance. However, perceived benefit associated with insurance is not universally shared by stakeholders partly due to their diverse risk attitudes. This study investigates the implied seismic design preference with insurance options for decisionmakers of bounded rationality whose preferences could be adequately represented by the cumulative prospect theory (CPT). The investigation is focused on assessing the sensitivity of the implied seismic design preference with insurance options to model parameters of the CPT and to fair and unfair insurance arrangements. Numerical results suggest that human cognitive limitation and risk perception can affect the implied seismic design preference by the CPT significantly. The mandatory purchase of fair insurance will lead the implied seismic design preference to the optimum design level that is dictated by the minimum expected lifecycle cost rule. Unfair insurance decreases the expected gain as well as its associated variability, which is preferred by risk-averse decisionmakers. The obtained results of the implied preference for the combination of the seismic design level and insurance option suggest that property owners, financial institutions, and municipalities can take advantage of affordable insurance to establish successful seismic risk management strategies.

  6. The Consistency of Quantum Mechanics Implies its Non-Determinism

    OpenAIRE

    Reznikoff, Iegor

    2010-01-01

    In a previous paper (arXiv:1008.3661v1[quant-ph] 21 Aug 2010), we have given a purely logical proof of the Conway and Kochen Free Will theorem in QM: the freedom of the observer implies the freedom of the observed particle. Here we show that the hypothesis of the observer's freedom is not necessary: the assumption of the (informal) consistency (non contradiction) of QM implies its non-determinism relative to physical events (the freedom of observed particles).

  7. INTRODUCTION Family planning implies the ability of individuals ...

    African Journals Online (AJOL)

    INTRODUCTION. Family planning implies the ability of individuals and couples to anticipate and attain their desired number of children by spacing and timing their births. It is achieved through the use of contraceptive methods and the treatment of involuntary infertility. The availability of family planning does more than ...

  8. The Forecast Performance of Competing Implied Volatility Measures

    DEFF Research Database (Denmark)

    Tsiaras, Leonidas

    volatility (CIV) measures are explored. For all pair-wise comparisons, it is found that a CIV measure that is closely related to the model-free implied volatility, nearly always delivers the most accurate forecasts for the majority of the firms. This finding remains consistent for different forecast horizons......, volatility definitions, loss functions and forecast evaluation settings....

  9. Estimating option-implied distributions in illiquid markets and ...

    African Journals Online (AJOL)

    Estimating option-implied distributions in illiquid markets and implementing the Ross recovery theorem. Emlyn Flint, Eben Maré. Abstract. In this research we describe how forward-looking information on the statistical properties of an asset can be extracted directly from options market data and demonstrate how this can be ...

  10. Brain activity accompanying perception of implied motion in abstract paintings.

    Science.gov (United States)

    Kim, Chai-Youn; Blake, Randolph

    2007-01-01

    Early 20th century artists including Duchamp and Balla tried to portray moving objects on a static canvas by superimposing objects in successive portrayals of an action. We investigated whether implied motion in those paintings is associated with activation of motion-sensitive area MT+. In Experiment 1, we found that observers rated these kinds of paintings higher in portraying motion than they did other abstract paintings in which motion is not intended. We also found that observers who had previously experienced abstract paintings with implied motion tended to give higher motion ratings to that class of paintings. In Experiment 2, we used functional magnetic resonance imaging (fMRI) to measure brain activity of observers while viewing abstract paintings receiving the highest and the lowest motion rating scores in Experiment 1. We found MT+, but not primary visual cortex (V1), showed greater BOLD responses to abstract paintings with implied motion than to abstract paintings with little motion impression, but only in observers with prior experience viewing those kinds of paintings. These results imply that the neural machinery ordinarily engaged during perception of real visual motion is activated when people view paintings explicitly designed to convey a sense of visual motion. Experience, however, is necessary to achieve this sense of motion.

  11. Fish introductions in the former Soviet Union: The Sevan trout (Salmo ischchan - 80 years later.

    Directory of Open Access Journals (Sweden)

    Wiesław Bogdanowicz

    Full Text Available The Soviet Union played the leading role in fish introductions in Eurasia. However, only 3% of all introductions prior to 1978 gave a commercial benefit. One of the noteworthy examples appears to be the Sevan trout (Salmo ischchan Kessler, 1877-an endemic salmonid of Lake Sevan in Armenia. This species has been introduced to Kirghizstan, Kazakhstan, and Uzbekistan, however, only the Kirghiz population has persisted in relatively high numbers. In this paper we provide the first extensive molecular study of S. ischchan using samples from the native population from Lake Sevan and three hatcheries in Armenia, as well as from the population introduced to Lake Issyk Kul in Kirghizstan. The Kirghiz population has been isolated since the introductions took place in 1930 and 1936. Our results, based on 11 nuclear microsatellites and a 905 bp fragment of the mitochondrial control region suggest that hatcheries have maintained genetic variability by way of ongoing translocations of individuals from Lake Sevan. Simultaneously, significant Garza-Williamson M-values suggest that bottlenecks could have reduced the genetic variability of the wild populations in the past. This hypothesis is supported by historical data, indicating highly manipulated water-level regulations and poaching as two main factors that dramatically impact fish abundance in the lake. On the other hand, a similar situation has been observed in Kirghizstan, but this population likely rebounded from small population size faster than the other populations examined. The Kirghiz population is significantly genetically differentiated from the other groups and have morphological features and biological attributes not observed in the source population. Genetic data imply that the effective population size in the native population is lower than that found in the introduced population, suggesting that some active protection of the Lake Sevan population may be needed urgently.

  12. Implied Movement in Static Images Reveals Biological Timing Processing

    Directory of Open Access Journals (Sweden)

    Francisco Carlos Nather

    2015-08-01

    Full Text Available Visual perception is adapted toward a better understanding of our own movements than those of non-conspecifics. The present study determined whether time perception is affected by pictures of different species by considering the evolutionary scale. Static (“S” and implied movement (“M” images of a dog, cheetah, chimpanzee, and man were presented to undergraduate students. S and M images of the same species were presented in random order or one after the other (S-M or M-S for two groups of participants. Movement, Velocity, and Arousal semantic scales were used to characterize some properties of the images. Implied movement affected time perception, in which M images were overestimated. The results are discussed in terms of visual motion perception related to biological timing processing that could be established early in terms of the adaptation of humankind to the environment.

  13. What is Implied When Researchers Claim to Use a Theory?

    Science.gov (United States)

    Palmér, Hanna; Roos, Helena

    2017-01-01

    The focus of this article is on the use of theories and on what we imply when we in research claim to use a theory. In this article, diverse uses of one theory will be illustrated with reference to 10 different studies. The aim is not to evaluate or judge how the theory is used in these studies, but to discuss how the diverse uses of one and the…

  14. The marine life of sea trout (Salmo trutta)

    DEFF Research Database (Denmark)

    Del Villar, Diego

    -smolts as well as on the fish returning to freshwater after the marine stage. The results of my experiments increase the current knowledge of specific behavioural traits that sea trout displays during their marine life. Additionally, it provides new information on the early and late marine survival which......During my PhD. research project I have studied the marine migratory behaviour and survival of wild sea trout (Salmo trutta L.) juveniles when moving from freshwater to saltwater (i.e. smolts/post-smolts) in two different fjord systems. These studies are focused on the initial marine stage of post...... is needed for comprehensive management of sea trout populations in the area. The principal method used was telemetry (acoustic and PIT-telemetry) which enable studying migratory patterns of fish in the fjord (i.e. acoustic telemetry) and detecting the transitions from the marine to the riverine environments...

  15. 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

    During migration, animals are typically limited by their endogenous energetic resources which must be allocated to the physiological costs associated with locomotion, as well as avoiding and/or compensating for oxidative stress. To date, there have been few attempts to understand the role...... 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...... 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...

  16. Note de synthèse sur la sélection de niche spatiale et la compétition chez le jeune saumon Atlantique (Salmo salar) et la truite commune (Salmo trutta) en milieu lotique

    OpenAIRE

    HEGGENES J.; BAGLINIÈRE J. L.; CUNJAK R.

    1995-01-01

    La sélection de l'habitat analysée à partir d'un ensemble de données récoltées sur des cours d'eau hétérogènes du point de vue spatio-temporel doit être interprétée en fonction du site et de l'échelle d'étude. La microniche spatiale fondamentale du juvénile de saumon Atlantique et de truite commune est caractérisée en été par une forte préférence pour une faible valeur de la vitesse de courant focale en raison d'une stratégie de gain énergétique basée essentiellement sur une prise alimentaire...

  17. Note de synthèse sur la sélection de niche spatiale et la compétition chez le jeune saumon Atlantique (Salmo salar et la truite commune (Salmo trutta en milieu lotique

    Directory of Open Access Journals (Sweden)

    HEGGENES J.

    1995-04-01

    Full Text Available La sélection de l'habitat analysée à partir d'un ensemble de données récoltées sur des cours d'eau hétérogènes du point de vue spatio-temporel doit être interprétée en fonction du site et de l'échelle d'étude. La microniche spatiale fondamentale du juvénile de saumon Atlantique et de truite commune est caractérisée en été par une forte préférence pour une faible valeur de la vitesse de courant focale en raison d'une stratégie de gain énergétique basée essentiellement sur une prise alimentaire de la faune dérivante qui permet de maximiser les comportements de prise de position et d'attente du poisson. Cette microniche est également dépendante de la taille : chez le saumon, les plus gros parrs sont tolérants ; par contre chez la truite, une préférence accrue pour les habitats profonds est observée lorsqu'elles grossissent. La niche effective de la truite est relativement plus structurée par des valeurs élevées de la profondeur d'eau et des valeurs faibles de vitesse de courant lorsqu'elle est comparée à celle du saumon caractérisée par de faibles hauteurs d'eau et par des vitesses de courant élevées. Ces différences proviennent d'une plus grande tolérance du saumon pour les fortes vitesses de courant, combinée à un déplacement de la niche de cette espèce par suite d'une compétition avec la truite qui est plus agressive. Cette compétition interactive et interspécifique aboutit à une réduction de la niche spatiale effective chez le Saumon lorsque les paramètres vitesse de courant et profondeur d'eau sont pris en compte simultanément, et pas chez la truite.

  18. Atlantic salmon (Salmo salar require increased dietary levels of B-vitamins when fed diets with high inclusion of plant based ingredients

    Directory of Open Access Journals (Sweden)

    Gro-Ingunn Hemre

    2016-09-01

    Full Text Available Aiming to re-evaluate current recommendations for nutrient supplementations when Atlantic salmon are fed diets based on plant ingredients, two regression experiments, with parr and post-smolt, were conducted. A control diet was included to evaluate if ingredients supplied sufficient nutrients without any added nutrient package (NP. The nutrient package consisted of vitamins B, C, E, minerals, cholesterol, methionine, taurine and histidine. This paper focus on B-vitamins. In parr, growth, health and welfare parameters responded on NP additions, but this was not observed in the seawater stage. During three months of feeding, parr tripled their weight. Parr given diets added the NP above NRC (2011 showed improved protein retention, and reduced liver and viscera indices. Post-smolt fed the same diets during five months showed a doubling of weight, but did not respond to the variation in NP to the same extent as parr. Significant regressions were obtained in body compartments for several of the B-vitamins in the premix. Whole body biotin concentration was unaffected by micronutrient premix level, and mRNA expression of the enzymes dependent of biotin showed only weak increases with increased biotin. Muscle thiamine plateaued at a diet level similar to NRC (2011 recommendation in freshwater, and showed stable values independent on premix addition in seawater. The mRNA expression of the enzyme G6PDH (glucose-6-phosphate dehydrogenase is sensitive to thiamine availability; results did not indicate any need to add thiamine above levels recommended for fish in general. Niacin showed a steady increase in whole body concentrations as feed niacin increased. Muscle riboflavin peaked at a diet level of 12.4 mg kg−1. Sufficient riboflavin is important to avoid e.g., development of cataract. Cataract was not registered to be any problem, neither in fresh- nor in seawater. Cobalamin (B 12 in muscle and liver was saturated at 0.17 mg kg−1 diet. Muscle pyridoxine showed a dose-dependent level in muscle, and peaked around 10 mg kg −1 diet. White muscle ASAT (asparagine amino transferase activity steadily increased, with indications of stable values when dietary pyridoxine was around 10–16 mg kg −1 diet. Pantothenic acid increased in gill tissue up to a level of 5.5 mg kg −1 soft gill tissue; at a dietary level of 22 mg kg−1. Improved performance, and coverage of metabolic need for niacin was at a dietary level of 66 mg kg −1, riboflavin 10–12 mg kg−1, pyridoxine 10 mg kg−1 and panthotenic acid 22 mg kg−1. Based on these results, recommended B-vitamin supplementation in plant based diets for Atlantic salmon should be adjusted.

  19. Experimental susceptibility of Atlantic salmon Salmo salar and turbot Scophthalmus maximus to European freshwater and marine isolates of viral haemorrhagic septicaemia virus

    DEFF Research Database (Denmark)

    King, J.A.; Snow, M.; Skall, Helle Frank

    2001-01-01

    pathogenicity to Atlantic salmon. Virus was detected in some mortalities, however, demonstrating viral entry and replication. European marine VHS virus isolates do not appear to pose an imminent threat to the Atlantic salmon culture industry. Turbot were found to be refractive or of low susceptibility to marine...... of turbot culture to the VHS virus isolates that are enzootic to the European marine environment.......A number of viral haemorrhagic septicaemia (VHS) virus isolates of European marine origin were shown to be of low pathogenicity or non-pathogenic to Atlantic salmon parr by waterborne infection. A reference freshwater VHS virus isolate known to be highly pathogenic to rainbow trout was also of low...

  20. Characterization of a novel calicivirus causing systemic infection in atlantic salmon (Salmo salar L.: proposal for a new genus of caliciviridae.

    Directory of Open Access Journals (Sweden)

    Aase B Mikalsen

    Full Text Available The Caliciviridae is a family of viruses infecting humans, a wide range of animals, birds and marine fish and mammals, resulting in a wide spectrum of diseases. We describe the identification and genetic characterization of a novel calicivirus replicating in Atlantic salmon. The virus has a high prevalence in farmed salmon and is found in fish suffering from several diseases and conditions and also in presumable healthy fish. A challenge and vaccination trial shows that the calicivirus replicates in Atlantic salmon and establishes a systemic infection, which can be reduced by vaccination with formalin-inactivated virus preparation. The virus, named Atlantic salmon calicivirus (ASCV, is found in two genetically distinct variants, a cell culture isolated and a variant sequenced directly from field material. The genomes are 7,4 kb and contain two open reading frames where typical conserved amino acid motifs and domains predict a gene order reminiscent of calicivirus genomes. Phylogenetic analysis performed on extracted capsid amino acid sequences segregated the two ASCV variants in a unique cluster sharing root with the branch of noroviruses infecting humans and the unassigned Tulane virus and St-Valérien like viruses, infecting rhesus monkey and pig, respectively, with relatively large distance to the marine calicivirus subgroup of vesiviruses. Based on the analyses presented, the ASCV is predicted to represent a new genus of Caliciviridae for which we propose the name Salovirus.

  1. Atlantic salmon (Salmo salar) protein hydrolysate in diets for weaning piglets ─ effect on growth performance, intestinal morphometry and microbiota composition

    DEFF Research Database (Denmark)

    Opheim, Margareth; Strube, Mikael Lenz; Sterten, Hallgeir

    2016-01-01

    protein (Diet FM) and two diets in which different SPH replaced fishmeal in the FM diet. The experimental diets were fed to piglets from the day of weaning until 32 d postweaning. In addition to the record of performance data, an intestinal sampling for mucosal morphometry and microbiota 16S rRNA gene...... postweaning was detected. Only small differences in intestinal microbiota community and no differences in growth performance were detected between the experimental diets. To conclude, SPH seem to be an interesting novel protein source in weanling piglets....

  2. Changes in Morphological Indexes of Young Atlantic Salmon (Salmo salar L. Exposed to hEavy Metal (Zn, Cu, Ni, Cr, Pb, Cd Mixture: an Experimental Study

    Directory of Open Access Journals (Sweden)

    Gintarė Sauliutė

    2016-10-01

    Full Text Available Morphological indexes are indicative of toxicant effects in fish. Unfortunately, morphological parameters [gill-, liver-, kidney-, viscero-, etc., somatic indexes and the integrated condition factor (CF], are usually determined in field studies to assess the general fish condition under effect of multicomponent pollution and did not reflect the effects of specific polluting substances (e.g. heavy metals. The purpose of this study was to experimentally evaluate the effect of priority heavy metal model mixture formed based on Maximum-Allowable-Concentration accepted for Lithuanian receiving water bodies (Zn – 0.1, Cu – 0.01, Ni – 0.01, Cr – 0.01, Pb – 0.005 and Cd – 0.005 mg/L, respectively on condition parameters of one-year-old Atlantic salmon after seven-, fourteen- and twenty eight- day exposure. Significant changes in liver-, kidney- and viscero-somatic indexes were determined, while CF and branchio-somatic-index were found to be not indicative for such kind of the exposure. Correlation analysis between the parameters studied revealed a number of meaningful patterns. The obtained data were compared with the results of the field study in salmonid rivers.

  3. 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

    The essential amino acid l-tryptophan (Trp) is the immediate precursor of the neurotransmitter serotonin (5-HT). Supplementing Trp through diet has been shown to suppress the neuroendocrine stress response in vertebrates including teleosts. In salmonid fish, adjusting to the social environment...... for aquaculture. Fish were given feed containing 1, 2, 3 or 4 times the Trp content in normal feed for one week. Subsequently, the fish were reintroduced to feed containing the lowest Trp level, corresponding to standard commercial feed for a number of days prior to exposure to an acute confinement stressor....... 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...

  4. PCR survey for Paramoeba perurans in fauna, environmental samples and fish associated with marine farming sites for Atlantic salmon (Salmo salar L.).

    Science.gov (United States)

    Hellebø, A; Stene, A; Aspehaug, V

    2017-05-01

    Amoebic gill disease (AGD) caused by the amoeba Paramoeba perurans is an increasing problem in Atlantic salmon aquaculture. In the present PCR survey, the focus was to identify reservoir species or environmental samples where P. perurans could be present throughout the year, regardless of the infection status in farmed Atlantic salmon. A total of 1200 samples were collected at or in the proximity to farming sites with AGD, or with history of AGD, and analysed for the presence of P. perurans. No results supported biofouling organisms, salmon lice, biofilm or sediment to maintain P. perurans. However, during clinical AGD in Atlantic salmon, the amoeba were detected in several samples, including water, biofilm, plankton, several filter feeders and wild fish. It is likely that some of these samples were positive as a result of the continuous exposure through water. Positive wild fish may contribute to the spread of P. perurans. Cleaner fish tested positive for P. perurans when salmon tested negative, indicating that they may withhold the amoeba longer than salmon. The results demonstrate the high infection pressure produced from an AGD-afflicted Atlantic salmon population and thus the importance of early intervention to reduce infection pressure and horizontal spread of P. perurans within farms. © 2016 John Wiley & Sons Ltd.

  5. Molecular characterisation of key components of the mucosal immune system in Atlantic salmon (Salmo salar L) and transcriptome analysis of responses against the salmon louse (Lepeophtheirus salmonis)

    OpenAIRE

    Tadiso, Tariku Markos

    2012-01-01

    Mucosal immunity in mammals is mediated mainly by secretory immunoglobulin A (SIgA), which is produced by IgA plasma cells commonly located in the lamina propria, and a transport system involving the polymeric Ig receptor (pIgR). In teleost fish, IgM plays some roles associated with mucosal defence. Very recent findings indicate that IgT, an antibody exclusive to teleosts, might have a special role in mucosal immune responses, and a possible pIgR counterpart has been identified...

  6. Dietary cholesterol supplementation to a plant-based diet suppresses the complete pathway of cholesterol synthesis and induces bile acid production in Atlantic salmon (Salmo salar L.).

    Science.gov (United States)

    Kortner, Trond M; Björkhem, Ingemar; Krasnov, Aleksei; Timmerhaus, Gerrit; Krogdahl, Åshild

    2014-06-28

    Plants now supply more than 50 % of protein in Norwegian salmon aquafeeds. The inclusion of plant protein in aquafeeds may be associated with decreased lipid digestibility and cholesterol and bile salt levels, indicating that the replacement of fishmeal with plant protein could result in inadequate supplies of cholesterol in fish. A reduction in feed efficiency, fish growth and pathogen resistance is often observed in parallel to alterations in sterol metabolism. Previous studies have indicated that the negative effects induced by plant components can be attenuated when diets are supplemented with cholesterol. The present study evaluated the effects of dietary cholesterol supplementation (1·5 %) in Atlantic salmon fed a plant-based diet for 77 d. The weights of body, intestines and liver were recorded and blood, tissues, faeces, chyme and bile were sampled for the evaluation of effects on growth, nutrient utilisation and metabolism, and transcriptome and metabolite levels, with particular emphasis on sterol metabolism and organ structure and function. Cholesterol supplementation did not affect the growth or organ weights of Atlantic salmon, but seemed to promote the induction of cholesterol and plant sterol efflux in the intestine while suppressing sterol uptake. Cholesterol biosynthesis decreased correspondingly and conversion into bile acids increased. The marked effect of cholesterol supplementation on bile acid synthesis suggests that dietary cholesterol can be used to increase bile acid synthesis in fish. The present study clearly demonstrated how Atlantic salmon adjusted their metabolic functions in response to the dietary load of cholesterol. It has also expanded our understanding of sterol metabolism and turnover, adding to the existing, rather sparse, knowledge of these processes in fish.

  7. Effects of freshwater hyperoxia and hypercapnia and their influences on subsequent seawater transfer in Atlantic salmon (Salmo salar) smolts

    DEFF Research Database (Denmark)

    Brauner, Colin; Seidelin, Michel; Madsen, Steffen

    2000-01-01

    through oxidative cell damage. This resulted in reduced hypoosmoregulatory ability following subsequent transfer to seawater (SW), as indicated by changes in plasma ion levels, osmolality, and muscle water content, resulting in considerable mortalities. Interestingly, FW hCO2 appeared to enhance...

  8. Intestinal barrier function of Atlantic salmon (Salmo salar L. post smolts is reduced by common sea cage environments and suggested as a possible physiological welfare indicator

    Directory of Open Access Journals (Sweden)

    Ellis Tim

    2010-11-01

    Full Text Available Abstract Background Fish farmed under high intensity aquaculture conditions are subjected to unnatural environments that may cause stress. Therefore awareness of how to maintain good health and welfare of farmed fish is important. For Atlantic salmon held in sea cages, water flow, dissolved oxygen (DO levels and temperature will fluctuate over time and the fish can at times be exposed to detrimentally low DO levels and high temperatures. This experimental study investigates primary and secondary stress responses of Atlantic salmon post smolts to long-term exposure to reduced and fluctuating DO levels and high water temperatures, mimicking situations in the sea cages. Plasma cortisol levels and cortisol release to the water were assessed as indicators of the primary stress response and intestinal barrier integrity and physiological functions as indicators of secondary responses to changes in environmental conditions. Results Plasma cortisol levels were elevated in fish exposed to low (50% and 60% saturation DO levels and low temperature (9°C, at days 9, 29 and 48. The intestinal barrier function, measured as electrical resistance (TER and permeability of mannitol at the end of the experiment, were reduced at 50% DO, in both proximal and distal intestine. When low DO levels were combined with high temperature (16°C, plasma cortisol levels were elevated in the cyclic 1:5 h at 85%:50% DO group and fixed 50% DO group compared to the control (85% DO group at day 10 but not at later time points. The intestinal barrier function was clearly disturbed in the 50% DO group; TER was reduced in both intestinal regions concomitant with increased paracellular permeability in the distal region. Conclusions This study reveals that adverse environmental conditions (low water flow, low DO levels at low and high temperature, that can occur in sea cages, elicits primary and secondary stress responses in Atlantic salmon post smolts. The intestinal barrier function was significantly affected by prolonged hypoxic stress even when no primary stress response was observed. This suggests that intestinal barrier function is a good experimental marker for evaluation of chronic stress and that it can be a valuable tool to study the impact of various husbandry conditions on health and welfare of farmed Atlantic salmon.

  9. Distribution, feeding and growth of hatchery-reared Atlantic salmon (Salmo salar L. parr stocked into rivers with various abiotic conditions

    Directory of Open Access Journals (Sweden)

    Nikolaev A. M.

    2017-06-01

    Full Text Available Within the research of efficiency of Atlantic salmon the artificial reproduction, feeding rate, distribution and growth of farm-raised one-year-old Atlantic salmon have been examined. The fish has been released into nursery areas with different hydrological characteristics located in the Rivers Kola, Umba, Srednyaya and Akkim in the Murmansk region. The observations have being conducted for 1–5 months since the moment of fish release. In natural habitat, juveniles rapidly distribute downstream and upstream regardless of water temperature, depth and current velocity. In all examined nursery areas adapting one-year-old juveniles prefer to stay at weak current sites close to the shore, hiding in the gravel. In all the cases farmed parr shows high feed rate, but qualitative composition of their food differs significantly from food composition of wild juveniles. Revealed peculiarities of adapting parr's distribution and qualitative food composition indicate the impact of long-term rearing at hatcheries on fish behavior. Growth rate of one-year-old juveniles is arcwise connected with fraction composition of gravel and the level of bottom fouling: the bigger bottom rocks are and the thicker the fouling is, the more intensive fish growth is. The revealed correlations have been described with equations of linear regression. Connections between juvenile growth and water temperature, current velocity and depth of the area have not been detected. The research outcomes could provide a basis for scientific advice for planning release sites and number of released one-year-old Atlantic salmon by hatcheries in the Murmansk region.

  10. SURVIE EMBRYONNAIRE DU SAUMON ATLANTIQUE (SALMO SALAR L. DANS UN COURS D’EAU DU SUD DE SON AIRE DE RÉPARTITION, LA NIVELLE

    Directory of Open Access Journals (Sweden)

    DUMAS J.

    2007-01-01

    Full Text Available L’évaluation de la survie du saumon Atlantique entre la ponte et l’émergence des alevins hors des graviers est réalisée dans le bassin de la Nivelle dans les domaines accessible (trois tronçons et non accessible (trois tronçons aux géniteurs. Pour ce faire, des capsules d’incubation de 12 cm3, contenant des œufs fraîchement fécondés, sont insérées dans des frayères artificielles et naturelles. Le débit et la température de l’eau de surface, l’oxygène dissous des eaux de surface et interstitielle et les caractéristiques granulométriques du substrat des frayères sont contrôlés pendant toute la durée de l’expérience. La survie, de 28,6 % en moyenne dans l’ensemble des sites, est plus élevée dans les tronçons de l’amont (52,7 % dans la Très Haute Nivelle et son affluent, le Lapitxuri que dans les autres sites, dont ceux actuellement colonisés par l’espèce (21,5 %. Il n’est pas observé de différence de survie entre les frayères artificielles et naturelles. Les mortalités interviennent essentiellement lors des épisodes de crues avant l’éclosion. Une corrélation positive forte existe entre la saturation en oxygène de l’eau interstitielle et la survie. Pour une saturation minimum en oxygène au-dessous de 62 %, la survie reste inférieure à 27 %. En revanche, la composition granulométrique du substrat ne semble pas agir directement sur la survie. Ce facteur n’étant pas corrélé avec l’oxygène dissous, ceci suggère que dans ce cours d’eau, le flux circulant dans les frayères ne provient pas uniquement de l’eau de surface, mais aussi de la nappe alluviale pauvre en oxygène dissous.

  11. Effects of genotype and dietary fish oil replacement with vegetable oil on the intestinal transcriptome and proteome of Atlantic salmon (Salmo salar).

    Science.gov (United States)

    Morais, Sofia; Silva, Tomé; Cordeiro, Odete; Rodrigues, Pedro; Guy, Derrick R; Bron, James E; Taggart, John B; Bell, J Gordon; Tocher, Douglas R

    2012-09-04

    Expansion of aquaculture requires alternative feeds and breeding strategies to reduce dependency on fish oil (FO) and better utilization of dietary vegetable oil (VO). Despite the central role of intestine in maintaining body homeostasis and health, its molecular response to replacement of dietary FO by VO has been little investigated. This study employed transcriptomic and proteomic analyses to study effects of dietary VO in two family groups of Atlantic salmon selected for flesh lipid content, 'Lean' or 'Fat'. Metabolism, particularly of lipid and energy, was the functional category most affected by diet. Important effects were also measured in ribosomal proteins and signalling. The long-chain polyunsaturated fatty acid (LC-PUFA) biosynthesis pathway, assessed by fatty acid composition and gene expression, was influenced by genotype. Intestinal tissue contents of docosahexaenoic acid were equivalent in Lean salmon fed either a FO or VO diet and expression of LC-PUFA biosynthesis genes was up-regulated in VO-fed fish in Fat salmon. Dietary VO increased lipogenesis in Lean fish, assessed by expression of FAS, while no effect was observed on β-oxidation although transcripts of the mitochondrial respiratory chain were down-regulated, suggesting less active energetic metabolism in fish fed VO. In contrast, dietary VO up-regulated genes and proteins involved in detoxification, antioxidant defence and apoptosis, which could be associated with higher levels of polycyclic aromatic hydrocarbons in this diet. Regarding genotype, the following pathways were identified as being differentially affected: proteasomal proteolysis, response to oxidative and cellular stress (xenobiotic and oxidant metabolism and heat shock proteins), apoptosis and structural proteins particularly associated with tissue contractile properties. Genotype effects were accentuated by dietary VO. Intestinal metabolism was affected by diet and genotype. Lean fish may have higher responsiveness to low dietary n-3 LC-PUFA, up-regulating the biosynthetic pathway when fed dietary VO. As global aquaculture searches for alternative oils for feeds, this study alerts to the potential of VO introducing contaminants and demonstrates the detoxifying role of intestine. Finally, data indicate genotype-specific responses in the intestinal transcriptome and proteome to dietary VO, including possibly structural properties of the intestinal layer and defence against cellular stress, with Lean fish being more susceptible to diet-induced oxidative stress.

  12. Functional Genomic Analysis of the Impact of Camelina (Camelina sativa) Meal on Atlantic Salmon (Salmo salar) Distal Intestine Gene Expression and Physiology.

    Science.gov (United States)

    Brown, Tyler D; Hori, Tiago S; Xue, Xi; Ye, Chang Lin; Anderson, Derek M; Rise, Matthew L

    2016-06-01

    The inclusion of plant meals in diets of farmed Atlantic salmon can elicit inflammatory responses in the distal intestine (DI). For the present work, fish were fed a standard fish meal (FM) diet or a diet with partial replacement of FM with solvent-extracted camelina meal (CM) (8, 16, or 24 % CM inclusion) during a 16-week feeding trial. A significant decrease in growth performance was seen in fish fed all CM inclusion diets (Hixson et al. in Aquacult Nutr 22:615-630, 2016). A 4x44K oligonucleotide microarray experiment was carried out and significance analysis of microarrays (SAM) and rank products (RP) methods were used to identify differentially expressed genes between the DIs of fish fed the 24 % CM diet and those fed the FM diet. Twelve features representing six known transcripts and two unknowns were identified as CM responsive by both SAM and RP. The six known transcripts (including thioredoxin and ependymin), in addition to tgfb, mmp13, and GILT, were studied using qPCR with RNA templates from all four experimental diet groups. All six microarray-identified genes were confirmed to be CM responsive, as was tgfb and mmp13. Histopathological analyses identified signs of inflammation in the DI of salmon fed CM-containing diets, including lamina propria and sub-epithelial mucosa thickening, infiltration of eosinophilic granule cells, increased goblet cells and decreased enterocyte vacuolization. All of these were significantly altered in 24 % CM compared to all other diets, with the latter two also altered in 16 % CM compared with 8 % CM and control diet groups. Significant correlation was seen between histological parameters as well as between five of the qPCR analyzed genes and histological parameters. These molecular biomarkers of inflammation arising from long-term dietary CM exposure will be useful in the development of CM-containing diets that do not have deleterious effects on salmon growth or physiology.

  13. Radiation-induced bystander effects in the Atlantic salmon (salmo salar L.) following mixed exposure to copper and aluminum combined with low-dose gamma radiation

    Energy Technology Data Exchange (ETDEWEB)

    Mothersill, Carmel; Seymour, Colin B. [McMaster University, Medical Physics and Applied Radiation Sciences Department, Hamilton, ON (Canada); Norwegian University of Life Sciences, Department of Plant and Environmental Sciences, Aas (Norway); Smith, Richard W. [McMaster University, Medical Physics and Applied Radiation Sciences Department, Hamilton, ON (Canada); Heier, Lene Soerlie; Teien, Hans-Christian; Land, Ole Christian; Oughton, Deborah; Salbu, Brit [Norwegian University of Life Sciences, Department of Plant and Environmental Sciences, Aas (Norway)

    2014-03-15

    Very little is known about the combined effects of low doses of heavy metals and radiation. However, such ''multiple stressor'' exposure is the reality in the environment. In the work reported in this paper, fish were exposed to cobalt 60 gamma irradiation with or without copper or aluminum in the water. Doses of radiation ranged from 4 to 75 mGy delivered over 48 or 6 h. Copper doses ranged from 10 to 80 μg/L for the same time period. The aluminum dose was 250 μg/L. Gills and skin were removed from the fish after exposure and explanted in tissue culture flasks for investigation of bystander effects of the exposures using a stress signal reporter assay, which has been demonstrated to be a sensitive indicator of homeostatic perturbations in cells. The results show complex synergistic interactions of radiation and copper. Gills on the whole produce more toxic bystander signals than skin, but the additivity scores show highly variable results which depend on dose and time of exposure. The impacts of low doses of copper and low doses of radiation are greater than additive, medium levels of copper alone have a similar level of effect of bystander signal toxicity to the low dose. The addition of radiation stress, however, produces clear protective effects in the reporters treated with skin-derived medium. Gill-derived medium from the same fish did not show protective effects. Radiation exposure in the presence of 80 μg/L led to highly variable results, which due to animal variation were not significantly different from the effect of copper alone. The results are stressor type, stressor concentration and time dependent. Clearly co-exposure to radiation and heavy metals does not always lead to simple additive effects. (orig.)

  14. 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)

    National Research Council Canada - National Science Library

    Norman, Joseph D; Robinson, Mike; Glebe, Brian; Ferguson, Moira M; Danzmann, Roy G

    2012-01-01

    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...

  15. Assessing peracetic acid as a means to control post-vaccination Saprolegniasis in Atlantic salmon Salmo salar parr in recirculation aquaculture systems

    Science.gov (United States)

    Land-based closed containment facilities, utilizing recirculation aquaculture system (RAS) technologies, can reduce or eliminate the introduction of obligate fish pathogens. Regardless, the presence of opportunistic pathogens must be assumed, and these agents can cause disease during unfavorable con...

  16. Evaluating the chronic effects of nitrate on the health and performance of post-smolt Atlantic salmon Salmo salar in freshwater recirculation aquaculture systems

    Science.gov (United States)

    Commercial production of Atlantic salmon smolts, post-smolts, and market-size fish using land-based recirculation aquaculture systems (RAS) is expanding. RAS generally provide a nutrient-rich environment in which nitrate accumulates as an end-product of nitrification. An 8-month study was conducted ...

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

    Science.gov (United States)

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

  18. Estimation of breeding values for uniformity of growth in Atlantic salmon (Salmo salar) using pedigree relationships or single-step genomic evaluation.

    Science.gov (United States)

    Sae-Lim, Panya; Kause, Antti; Lillehammer, Marie; Mulder, Han A

    2017-03-07

    In farmed Atlantic salmon, heritability for uniformity of body weight is low, indicating that the accuracy of estimated breeding values (EBV) may be low. The use of genomic information could be one way to increase accuracy and, hence, obtain greater response to selection. Genomic information can be merged with pedigree information to construct a combined relationship matrix ([Formula: see text] matrix) for a single-step genomic evaluation (ssGBLUP), allowing realized relationships of the genotyped animals to be exploited, in addition to numerator pedigree relationships ([Formula: see text] matrix). We compared the predictive ability of EBV for uniformity of body weight in Atlantic salmon, when implementing either the [Formula: see text] or [Formula: see text] matrix in the genetic evaluation. We used double hierarchical generalized linear models (DHGLM) based either on a sire-dam (sire-dam DHGLM) or an animal model (animal DHGLM) for both body weight and its uniformity. With the animal DHGLM, the use of [Formula: see text] instead of [Formula: see text] significantly increased the correlation between the predicted EBV and adjusted phenotypes, which is a measure of predictive ability, for both body weight and its uniformity (41.1 to 78.1%). When log-transformed body weights were used to account for a scale effect, the use of [Formula: see text] instead of [Formula: see text] produced a small and non-significant increase (1.3 to 13.9%) in predictive ability. The sire-dam DHGLM had lower predictive ability for uniformity compared to the animal DHGLM. Use of the combined numerator and genomic relationship matrix ([Formula: see text]) significantly increased the predictive ability of EBV for uniformity when using the animal DHGLM for untransformed body weight. The increase was only minor when using log-transformed body weights, which may be due to the lower heritability of scaled uniformity, the lower genetic correlation of transformed body weight with its uniformity compared to the untransformed traits, and the small number of genotyped animals in the reference population. This study shows that ssGBLUP increases the accuracy of EBV for uniformity of body weight and is expected to increase response to selection in uniformity.

  19. Estimation of breeding values for uniformity of growth in Atlantic salmon (Salmo salar) using pedigree relationships or single-step genomic evaluation

    NARCIS (Netherlands)

    Sae-Lim, Panya; Kause, Antti; Lillehammer, Marie; Mulder, Herman

    2017-01-01

    Background: In farmed Atlantic salmon, heritability for uniformity of body weight is low, indicating that the accuracy of estimated breeding values (EBV) may be low. The use of genomic information could be one way to increase accuracy and, hence, obtain greater response to selection. Genomic

  20. Significance of volatile compounds produced by spoilage bacteria in vacuum-packed cold-smoked salmon ( Salmo salar ) analyzed by GC-MS and multivariate regression

    DEFF Research Database (Denmark)

    Jørgensen, Lasse Vigel; Huss, Hans Henrik; Dalgaard, Paw

    2001-01-01

    , 1- penten-3-ol, and 1-propanol. The potency and importance of these compounds was confirmed by gas chromatography- olfactometry. The present study provides valuable information on the bacterial reactions responsible for spoilage off-flavors of cold-smoked salmon, which can be used to develop...

  1. Transcriptional effects of metal-rich acid drainage water from the abandoned Løkken Mine on Atlantic salmon (Salmo salar) smolt.

    Science.gov (United States)

    Olsvik, Pål A; Ulvund, John B; Teien, Hans C; Urke, Henning A; Lie, Kai K; Kristensen, Torstein

    2016-01-01

    Runoff of metals represents one of the major environmental challenges related to historic and ongoing mining activity. In this study, transcriptomics (direct RNA sequencing [RNA-seq] and reverse-transcription quantitative polymerase chain reaction [RT-qPCR]) was used to predict toxicity of metal-rich acid mine drainage (AMD) water collected in the abandoned copper (Cu) mine called Løkken Mine on Atlantic salmon liver and kidney, the main target organs of Cu-induced toxicity in fish. Smolts were exposed to control and diluted AMD water, which contains a mixture of metals but is especially enriched with Cu, at 4 concentrations in freshwater (FW) for 96 h, and then were transferred to and kept in seawater (SW) for another 24 h. Significant accumulation of Cu was observed in the gills, but not liver and kidney tissues, after 96 h of exposure. Short-term exposure to metal-rich ADM (high exposure group) significantly upregulated 3201 transcripts and downregulated 3782 transcripts in liver. The strongest effect attributed to exposure was observed on the KEGG pathway "protein processing in endoplasmic reticulum," followed by "steroid biosynthesis." Gene ontology (GO) analysis suggested that exposure predominantly affected "protein folding," possibly by disrupting disulfide bonds as a result of endoplasmic-reticulum-generated stress, and "sterol biosynthetic processes." Transfer to uncontaminated SW for 24 h amended the transcription of several genes, suggesting a transient effect of treatment on some mechanisms. In conclusion, the data show that trace metals in AMD from abandoned pyrite mines might disturb molecular mechanisms linked to protein folding in Atlantic salmon smolt endoplasmic reticulum.

  2. The role of extracellular matrix components in pin bone attachments during storage-a comparison between farmed Atlantic salmon (Salmo salar) and cod (Gadus morhua L.).

    Science.gov (United States)

    Rønning, Sissel B; Østbye, Tone-Kari; Krasnov, Aleksei; Vuong, Tram T; Veiseth-Kent, Eva; Kolset, Svein O; Pedersen, Mona E

    2017-04-01

    Pin bones represent a major problem for processing and quality of fish products. Development of methods of removal requires better knowledge of the pin bones' attachment to the muscle and structures involved in the breakdown during loosening. In this study, pin bones from cod and salmon were dissected from fish fillets after slaughter or storage on ice for 5 days, and thereafter analysed with molecular methods, which revealed major differences between these species before and after storage. The connective tissue (CT) attaches the pin bone to the muscle in cod, while the pin bones in salmon are embedded in adipose tissue. Collagens, elastin, lectin-binding proteins and glycosaminoglycans (GAGs) are all components of the attachment site, and this differ between salmon and cod, resulting in a CT in cod that is more resistant to enzymatic degradation compared to the CT in salmon. Structural differences are reflected in the composition of transcriptome. Microarray analysis comparing the attachment sites of the pin bones with a reference muscle sample showed limited differences in salmon. In cod, on the other hand, the variances were substantial, and the gene expression profiles suggested difference in myofibre structure, metabolism and cell processes between the pin bone attachment site and the reference muscle. Degradation of the connective tissue occurs closest to the pin bones and not in the neighbouring tissue, which was shown using light microscopy. This study shows that the attachment of the pin bones in cod and salmon is different; therefore, the development of methods for removal should be tailored to each individual species.

  3. The role of extracellular matrix components in pin bone attachments during storage—a comparison between farmed Atlantic salmon (Salmo salar) and cod (Gadus morhua L.)

    OpenAIRE

    Rønning, Sissel Beate; Østbye, Tone-Kari K; Krasnov, Aleksei; Vuong, Tram Thu; Veiseth-Kent, Eva; Kolset, Svein Olav; Pedersen, Mona Elisabeth

    2016-01-01

    Pin bones represent a major problem for processing and quality of fish products. Development of methods of removal requires better knowledge of the pin bones? attachment to the muscle and structures involved in the breakdown during loosening. In this study, pin bones from cod and salmon were dissected from fish fillets after slaughter or storage on ice for 5?days, and thereafter analysed with molecular methods, which revealed major differences between these species before and after storage. T...

  4. A comparative study of the response to repeated chasing stress in Atlantic salmon (Salmo salar L.) parr and post-smolts.

    Science.gov (United States)

    Madaro, Angelico; Olsen, Rolf Erik; Kristiansen, Tore S; Ebbesson, Lars O E; Flik, Gert; Gorissen, Marnix

    2016-02-01

    When Atlantic salmon parr migrate from fresh water towards the sea, they undergo extensive morphological, neural, physiological and behavioural changes. Such changes have the potential to affect their responsiveness to various environmental factors that impose stress. In this study we compared the stress responses in parr and post-smolt salmon following exposure to repeated chasing stress (RCS) for three weeks. At the end of this period, all fish were challenged with a novel stressor and sampled before (T0) and after 1h (T1). Parr had a higher growth rate than post-smolts. Plasma cortisol declined in the RCS groups within the first week suggesting a rapid habituation/desensitisation of the endocrine stress axis. As a result of the desensitised HPI axis, RCS groups showed a reduced cortisol response when exposed to the novel stressor. In preoptic area (POA) crf mRNA levels were higher in all post-smolt groups compared to parr. 11βhsd2 decreased by RCS and by the novel stressor in post-smolt controls (T1), whereas no effect of either stress was seen in parr. The grs were low in all groups except for parr controls. In pituitary, parr controls had higher levels of crf1r mRNA than the other parr and post-smolt groups, whilst pomcb was higher in post-smolt control groups. Overall, 11βhsd2 transcript abundance in parr was lower than post-smolt groups; after the novel stressor pomcs, grs and mr were up-regulated in parr control (T1). In summary, we highlight differences in the central stress response between parr and post-smolt salmon following RCS. Copyright © 2015 Elsevier Inc. All rights reserved.

  5. Impacts of short-term acid and aluminum exposure on Atlantic salmon (Salmo salar) physiology: A direct comparison of parr and smolts

    Science.gov (United States)

    Monette, M.Y.; McCormick, S.D.

    2008-01-01

    Episodic acidification resulting in increased acidity and inorganic aluminum (Ali) is known to impact anadromous salmonids and has been identified as a possible cause of Atlantic salmon population decline. Sensitive life-stages such as smolts may be particularly vulnerable to impacts of short-term (days–week) acid/Al exposure, however the extent and mechanism(s) of this remain unknown. To determine if Atlantic salmon smolts are more sensitive than parr to short-term acid/Al, parr and smolts held in the same experimental tanks were exposed to control (pH 6.3–6.6, 11–37 μg l−1 Ali) and acid/Al (pH 5.0–5.4, 43–68 μg l−1 Ali) conditions in the lab, and impacts on ion regulation, stress response and gill Al accumulation were examined after 2 and 6 days. Parr and smolts were also held in cages for 2 and 6 days in a reference (Rock River, RR) and an acid/Al-impacted tributary (Ball Mountain Brook, BMB) of the West River in Southern Vermont. In the lab, losses in plasma Cl− levels occurred in both control parr and smolts as compared to fish sampled prior to the start of the study, however smolts exposed to acid/Al experienced additional losses in plasma Cl− levels (9–14 mM) after 2 and 6 days, and increases in plasma cortisol (4.3-fold) and glucose (2.9-fold) levels after 6 days, whereas these parameters were not significantly affected by acid/Al in parr. Gill Na+,K+-ATPase (NKA) activity was not affected by acid/Al in either life-stage. Both parr and smolts held at BMB (but not RR) exhibited declines in plasma Cl−, and increases in plasma cortisol and glucose levels; these differences were significantly greater in smolts after 2 days but similar in parr and smolts after 6 days. Gill NKA activity was reduced 45–54% in both life-stages held at BMB for 6 days compared to reference fish at RR. In both studies, exposure to acid/Al resulted in gill Al accumulation in parr and smolts, with parr exhibiting two-fold greater gill Al than smolts after 6 days. Our results indicate that smolts are more sensitive than parr to short-term acid/Al. Increased sensitivity of smolts appears to be independent of a reduction in gill NKA activity and greater gill Al accumulation. Instead, increased sensitivity of smolts is likely a result of both the acquisition of seawater tolerance while still in freshwater and heightened stress responsiveness in preparation for seawater entry and residence.

  6. Effects of dietary plant meal and soya-saponin supplementation on intestinal and hepatic lipid droplet accumulation and lipoprotein and sterol metabolism in Atlantic salmon (Salmo salar L.).

    Science.gov (United States)

    Gu, Min; Kortner, Trond M; Penn, Michael; Hansen, Anne Kristine; Krogdahl, Åshild

    2014-02-01

    Altered lipid metabolism has been shown in fish fed plant protein sources. The present study aimed to gain further insights into how intestinal and hepatic lipid absorption and metabolism are modulated by plant meal (PM) and soya-saponin (SA) inclusion in salmon feed. Post-smolt Atlantic salmon were fed for 10 weeks one of four diets based on fishmeal or PM, with or without 10 g/kg SA. PM inclusion resulted in decreased growth performance, excessive lipid droplet accumulation in the pyloric caeca and liver, and reduced plasma cholesterol levels. Intestinal and hepatic gene expression profiling revealed an up-regulation of the expression of genes involved in lipid absorption and lipoprotein (LP) synthesis (apo, fatty acid transporters, microsomal TAG transfer protein, acyl-CoA cholesterol acyltransferase, choline kinase and choline-phosphate cytidylyltransferase A), cholesterol synthesis (3-hydroxy-3-methylglutaryl-CoA reductase) and associated transcription factors (sterol regulatory element-binding protein 2 and PPARγ). SA inclusion resulted in reduced body pools of cholesterol and bile salts. The hepatic gene expression of the rate-limiting enzyme in bile acid biosynthesis (cytochrome P450 7A1 (cyp7a1)) as well as the transcription factor liver X receptor and the bile acid transporter abcb11 (ATP-binding cassette B11) was down-regulated by SA inclusion. A significant interaction was observed between PM inclusion and SA inclusion for plasma cholesterol levels. In conclusion, gene expression profiling suggested that the capacity for LP assembly and cholesterol synthesis was up-regulated by PM exposure, probably as a compensatory mechanism for excessive lipid droplet accumulation and reduced plasma cholesterol levels. SA inclusion had hypocholesterolaemic effects on Atlantic salmon, accompanied by decreased bile salt metabolism.

  7. Features in the Lipid Status of Two Generations of Fingerlings (0+ of Atlantic Salmon (Salmo salar L. Inhabiting the Arenga River (Kola Peninsula

    Directory of Open Access Journals (Sweden)

    Nina N. Nemova

    2015-07-01

    Full Text Available The present research focused on determining the lipid status of salmon fingerlings (0+ in early development after dispersal form groups of spawning nests in biotopes of different hydrological conditions. The revealed qualitative and quantitative differences in the levels of phospholipids and fatty acids among two generations of Atlantic salmon fingerlings (0+ living in different biotopes of the Arenga River (a tributary of the Varzuga River may be associated with the peculiarities of their genetically determined processes of the biosynthesis and modification of individual lipid classes and trophoecological factors (food spectrum, quality and availability of food objects, and hydrological regime. The research was organized to observe the dynamics of these developmental changes from ages 0+ to 2+.

  8. Development of a Rapid Real-Time PCR Method as a Tool To Quantify Viable Photobacterium phosphoreum Bacteria in Salmon (Salmo salar) Steaks

    DEFF Research Database (Denmark)

    Macé, Sabrina; Mamlouk, Kelthoum; Chipchakova, Stoyka

    2013-01-01

    -bp fragment of the gyrase subunit B gene (gyrB) of P. phosphoreum. The specificity of the two primers was demonstrated by using purified DNA from 81 strains of 52 different bacterial species. When these primers were used for real-time PCR in pure culture, a good correlation (R2 of 0.99) was obtained...

  9. Characterisation of the spoilage microbiota in raw salmon (Salmo salar) steaks stored under vacuum or modified atmosphere packaging combining conventional methods and PCR-TTGE.

    Science.gov (United States)

    Macé, Sabrina; Cornet, Josiane; Chevalier, Frédérique; Cardinal, Mireille; Pilet, Marie-France; Dousset, Xavier; Joffraud, Jean-Jacques

    2012-05-01

    In order to characterise the spoilage related to microbiota of raw salmon, a combination of culture-dependent and -independent methods, including PCR-TTGE, was used to analyse 3 raw salmon batches stored for 3 days at chilled temperature in modified atmosphere packaging (MAP) (50% CO₂/50% N₂) or under vacuum. Sensory evaluation, microbiological enumeration and chemical analysis were performed after 3, 7 and 10 days of storage. At the onset of spoilage, 65 bacterial isolates were picked from the plates. Thus, 13 different genera or species were identified by phenotypic and molecular tests: Serratia spp., Photobacterium phosphoreum, Yersinia intermedia, Hafnia alvei, Buttiauxella gaviniae, Pseudomonas sp., Carnobacterium maltaromaticum, Carnobacterium divergens, Lactococcus piscium, Lactobacillus fuchuensis, Vagococcus carniphilus, Leuconostoc gasicomitatum and Brochothrix thermosphacta. The PCR-TTGE profiles and band identification enabled a shift of the dominant populations during the storage to be visualised for all the batches, probably due to the temperature change and the packaging. At the beginning of storage, Pseudomonas sp. dominated the raw salmon microbiota while in the following days (7 and 10), P. phosphoreum and L. piscium were identified as the main bacterial groups. This study enhances the knowledge of MAP and vacuum-packed raw salmon spoilage microbiota. Copyright © 2011 Elsevier Ltd. All rights reserved.

  10. Development of a Rapid Real-Time PCR Method as a Tool To Quantify Viable Photobacterium phosphoreum Bacteria in Salmon (Salmo salar) Steaks

    OpenAIRE

    Macé, Sabrina; Mamlouk, Kelthoum; Chipchakova, Stoyka; Prévost, Hervé; Joffraud, Jean-jacques; Dalgaard, Paw,; Pilet, Marie-France; Dousset, Xavier

    2013-01-01

    A specific real-time PCR quantification method combined with a propidium monoazide sample treatment step was developed to determine quantitatively the viable population of the Photobacterium phosphoreum species group in raw modified-atmosphere-packed salmon. Primers were designed to amplify a 350-bp fragment of the gyrase subunit B gene (gyrB) of P. phosphoreum. The specificity of the two primers was demonstrated by using purified DNA from 81 strains of 52 different bacterial species. When th...

  11. Development of a rapid real-time PCR method as a tool to quantify viable Photobacterium phosphoreum bacteria in salmon (Salmo salar) steaks.

    Science.gov (United States)

    Macé, Sabrina; Mamlouk, Kelthoum; Chipchakova, Stoyka; Prévost, Hervé; Joffraud, Jean-Jacques; Dalgaard, Paw; Pilet, Marie-France; Dousset, Xavier

    2013-04-01

    A specific real-time PCR quantification method combined with a propidium monoazide sample treatment step was developed to determine quantitatively the viable population of the Photobacterium phosphoreum species group in raw modified-atmosphere-packed salmon. Primers were designed to amplify a 350-bp fragment of the gyrase subunit B gene (gyrB) of P. phosphoreum. The specificity of the two primers was demonstrated by using purified DNA from 81 strains of 52 different bacterial species. When these primers were used for real-time PCR in pure culture, a good correlation (R(2) of 0.99) was obtained between this method and conventional enumeration on marine agar (MA). Quantification was linear over 5 log units as confirmed by using inoculated salmon samples. On naturally contaminated fresh salmon, the new real-time PCR method performed successfully with a quantification limit of 3 log CFU/g. A correlation coefficient (R(2)) of 0.963 was obtained between the PCR method and classic enumeration on MA, followed by identification of colonies (290 isolates identified by real-time PCR or by 16S rRNA gene sequencing). A good correlation with an R(2) of 0.940 was found between the new PCR method and an available specific conductance method for P. phosphoreum. This study presents a rapid tool for producing reliable quantitative data on viable P. phosphoreum bacteria in fresh salmon in 6 h. This new culture-independent method will be valuable for future fish inspection, the assessment of raw material quality in fish processing plants, and studies on the ecology of this important specific spoilage microorganism.

  12. Microbial spoilage and formation of biogenic amines in fresh and thawed modified atmosphere-packed salmon ( Salmo salar ) at 2 degrees C

    DEFF Research Database (Denmark)

    Emborg, Jette; Laursen, B.G.; Rathjen, T.

    2002-01-01

    series of storage trials with naturally contaminated fresh and thawed modified atmosphere-packed (MAP) salmon at 2 degrees C. Photobacterium phosphoreum dominated the spoilage microflora of fresh MAP salmon at more than 106 cfu g-1 and the activity of this specific spoilage organism (SSO) limited......-2 weeks. Carnobacterium piscicola dominated the spoilage microflora of thawed MAP salmon and probably produced the ca 40 mg kg-1 tyramine detected in this product at the end of its shelf life.Conclusions: Photobacterium phosphoreum dominated the spoilage microflora of fresh MAP salmon but produced only...... the shelf life of the product to ca 14 and 21 d in the two experiments. Despite the high levels of P. phosphoreum, less than 20 mg kg-1 histamine was observed in fresh MAP salmon prior to sensory spoilage. Freezing eliminated P. phosphoreum and extended the shelf life of MAP salmon at 2 degrees C by 1...

  13. Targeted mutagenesis in Atlantic salmon (Salmo salar L. using the CRISPR/Cas9 system induces complete knockout individuals in the F0 generation.

    Directory of Open Access Journals (Sweden)

    Rolf B Edvardsen

    Full Text Available Understanding the biological function behind key proteins is of great concern in Atlantic salmon, both due to a high commercial importance and an interesting life history. Until recently, functional studies in salmonids appeared to be difficult. However, the recent discovery of targeted mutagenesis using the CRISPR/Cas9 (clustered regularly interspaced palindromic repeats/CRISPR-associated system enables performing functional studies in Atlantic salmon to a great extent. We used the CRISPR/Cas9 system to target two genes involved in pigmentation, tyrosinase (tyr and solute carrier family 45, member 2 (slc45a2. Embryos were assayed for mutation rates at the 17 somite stage, where 40 and 22% of all injected embryos showed a high degree of mutation induction for slc45a2 and tyr, respectively. At hatching this mutation frequency was also visible for both targeted genes, displaying a graded phenotype ranging from complete lack of pigmentation to partial loss and normal pigmentation. CRISPRslc45a2/Cas9 injected embryos showing a complete lack of pigmentation or just a few spots of pigments also lacked wild type sequences when assaying more than 80 (slc45a2 sequence clones from whole embryos. This indicates that CRISPR/Cas9 can induce double-allelic knockout in the F0 generation. However, types and frequency of indels might affect the phenotype. Therefore, the variation of indels was assayed in the graded pigmentation phenotypes produced by CRISPR/Cas9-slc45a2. The results show a tendency for fewer types of indels formed in juveniles completely lacking pigmentation compared to juveniles displaying partial pigmentation. Another interesting observation was a high degree of the same indel type in different juveniles. This study shows for the first time successful use of the CRISPR/Cas9 technology in a marine cold water species. Targeted double-allelic mutations were obtained and, though the level of mosaicism has to be considered, we demonstrate that F0 fish can be used for functional studies in Atlantic salmon.

  14. Development of a Rapid Real-Time PCR Method as a Tool To Quantify Viable Photobacterium phosphoreum Bacteria in Salmon (Salmo salar) Steaks

    Science.gov (United States)

    Macé, Sabrina; Mamlouk, Kelthoum; Chipchakova, Stoyka; Prévost, Hervé; Joffraud, Jean-Jacques; Dalgaard, Paw; Pilet, Marie-France

    2013-01-01

    A specific real-time PCR quantification method combined with a propidium monoazide sample treatment step was developed to determine quantitatively the viable population of the Photobacterium phosphoreum species group in raw modified-atmosphere-packed salmon. Primers were designed to amplify a 350-bp fragment of the gyrase subunit B gene (gyrB) of P. phosphoreum. The specificity of the two primers was demonstrated by using purified DNA from 81 strains of 52 different bacterial species. When these primers were used for real-time PCR in pure culture, a good correlation (R2 of 0.99) was obtained between this method and conventional enumeration on marine agar (MA). Quantification was linear over 5 log units as confirmed by using inoculated salmon samples. On naturally contaminated fresh salmon, the new real-time PCR method performed successfully with a quantification limit of 3 log CFU/g. A correlation coefficient (R2) of 0.963 was obtained between the PCR method and classic enumeration on MA, followed by identification of colonies (290 isolates identified by real-time PCR or by 16S rRNA gene sequencing). A good correlation with an R2 of 0.940 was found between the new PCR method and an available specific conductance method for P. phosphoreum. This study presents a rapid tool for producing reliable quantitative data on viable P. phosphoreum bacteria in fresh salmon in 6 h. This new culture-independent method will be valuable for future fish inspection, the assessment of raw material quality in fish processing plants, and studies on the ecology of this important specific spoilage microorganism. PMID:23396343

  15. Additive effects of enhanced ambient ultraviolet B radiation and increased temperature on immune function, growth and physiological condition of juvenile (parr) Atlantic Salmon, Salmo salar.

    Science.gov (United States)

    Jokinen, Ilmari E; Salo, Harri M; Markkula, Eveliina; Rikalainen, Kaisa; Arts, Michael T; Browman, Howard I

    2011-01-01

    Climate change models predict increased ultraviolet B (UVB) radiation levels due to stratospheric ozone depletion and global warming. In order to study the impact of these two environmental stressors acting simultaneously on the physiology of fish, Atlantic salmon parr were exposed, for 8 weeks in outdoor tanks, to different combinations of UVB radiation (depleted and enhanced) and temperature (standard rearing temperature of 14 °C or 19 °C). The immune function (plasma IgM, lysozyme activity and complement bacteriolytic activity), growth (body weight) and physiological condition (haematocrit and plasma protein concentration) of the fish were determined. Increased UVB level, regardless of water temperature, had a negative effect on immune function parameters, growth and physiological condition. Higher temperature increased plasma IgM concentration but had a negative effect on complement bacteriolytic activity under both spectral treatments. Increased temperature, irrespective of UVB level, increased fish growth but negatively affected haematocrit and plasma protein. Exposing the fish to enhanced UVB at elevated temperature increased plasma IgM concentration and slightly improved growth. However, complement activity and physiological condition parameters decreased more than when the fish were exposed to each stressor separately. The changes were mainly additive; no interactive or synergistic effects were observed. The negative impact of multiple stressors on immune function, together with predicted increases in pathogen load in warmer waters resulting from global climate change, suggest an increased risk to diseases in fishes. Copyright © 2010 Elsevier Ltd. All rights reserved.

  16. A comparison of the digestibility of a range of lupin and soybean protein products when fed to either Atlantic salmon (Salmo salar) or rainbow trout (Oncorhynchus mykiss)

    NARCIS (Netherlands)

    Glencross, B.D.; Carter, C.G.; Duijster, N.; Evans, D.R.; Dods, K.; McCafferty, P.; Hawkins, W.E.; Maas, van der R.; Sipsas, S.

    2004-01-01

    This study compares the digestibility of a series of lupin and soybean protein products when fed to either rainbow trout or Atlantic salmon. The test ingredients in the study, from one of two key grain resources (lupins: Lupinus angustifolius and soybeans), represented various levels of processing

  17. Atlantic salmon (Salmo salar) protein hydrolysate in diets for weaning piglets ─ effect on growth performance, intestinal morphometry and microbiota composition.

    Science.gov (United States)

    Opheim, Margareth; Strube, Mikael Lenz; Sterten, Hallgeir; Øverland, Margareth; Kjos, Nils Petter

    2016-01-01

    Salmon protein hydrolysates (SPH) from two different rest raw materials were evaluated in diets for weaning piglets. Four experimental diets were included in the study: a diet based on plant protein with soy protein as the main protein source (Diet PP), a diet based on fishmeal in exchange for soy protein (Diet FM) and two diets in which different SPH replaced fishmeal in the FM diet. The experimental diets were fed to piglets from the day of weaning until 32 d postweaning. In addition to the record of performance data, an intestinal sampling for mucosal morphometry and microbiota 16S rRNA gene sequencing were performed at day 11 on a subset of the animals. The duodenal villi absorption area was significantly larger in piglets receiving Diets SPH compared with Diet PP (p diets. To conclude, SPH seem to be an interesting novel protein source in weanling piglets.

  18. Multiple genes for functional 6 fatty acyl desaturases (Fad) in Atlantic salmon (Salmo salar L.): gene and cDNA characterization, functional expression, tissue distribution and nutritional regulation.

    Science.gov (United States)

    Monroig, Oscar; Zheng, Xiaozhong; Morais, Sofia; Leaver, Michael J; Taggart, John B; Tocher, Douglas R

    2010-09-01

    Fish are the primary source in the human food basket of the n-3 long-chain polyunsaturated fatty acids, eicosapentaenoate (EPA; 20:5n-3) and docosahexaenoate (DHA; 22:6n-3), that are crucial to the health of higher vertebrates. Atlantic salmon are able to synthesize EPA and DHA from 18:3n-3 through reactions catalyzed by fatty acyl desaturases (Fad) and elongases of very long chain fatty acids. Previously, two cDNAs encoding functionally distinct Delta5 and Delta6 Fads were isolated, but screening of a genomic DNA library revealed the existence of more putative fad genes in the Atlantic salmon genome. In the present study, we show that there are at least four genes encoding putative Fad proteins in Atlantic salmon. Two genes, Delta6fad_a and Delta5fad, corresponded to the previously cloned Delta6 and Delta5 Fad cDNAs. Functional characterization by heterologous expression in yeast showed that the cDNAs for both the two further putative fad genes, Delta6fad_b and Delta6fad_c, had only Delta6 activity, converting 47 % and 12 % of 18:3n-3 to 18:4n-3, and 25 and 7 % of 18:2n-6 to 18:3n-6, for 6Fad_b and Delta6fad_c, respectively. Both 6fad_a and 6fad_b genes were highly expressed in intestine (pyloric caeca), liver and brain, with 6fad_b also highly expressed in gill, whereas 6fad_c transcript was found predominantly in brain, with lower expression levels in all other tissues. The expression levels of the 6fad_a gene in liver and the 6fad_b gene in intestine were significantly higher in fish fed diets containing vegetable oil compared to fish fed fish oil suggesting up-regulation in response to reduced dietary EPA and DHA. In contrast, no significant differences were found between transcript levels for 6fad_a in intestine, 6fad_b in liver, or 6fad_c in liver or intestine of fish fed vegetable oil compared to fish fed fish oil. The observed differences in tissue expression and nutritional regulation of the fad genes are discussed in relation to gene structures and fish physiology. 2010 Elsevier B.V. All rights reserved.

  19. Quantitative extraction of nucleotides from frozen muscle samples of Atlantic salmon ( Salmo salar ) and rainbow trout ( Oncorhynchus mykiss ) : Effects of time taken to sample and extraction method

    DEFF Research Database (Denmark)

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

    2000-01-01

    Muscle excised from the dorsal flank of Atlantic salmon and rainbow trout at death and up to 120 min postmortem (P.M.) was frozen in liquid N-2 and stored at -80C. Following acid extraction, on ice (method I), or dry ice (method 2) samples were analyzed for cyclic nucleotides to determine...... the effect of time to sample, and extraction method. There was no pattern of change in nucleotide profile in either species up to 10 min P.M. At 120 min P.M., Atlantic salmon muscle extracted by method 2 had a higher IMP concentration than at any other time but there was no difference in adenylates. Ignoring.......8 to -5C) prior to enzyme inactivation....

  20. Genotype-specific responses in Atlantic salmon (Salmo salar) subject to dietary fish oil replacement by vegetable oil: a liver transcriptomic analysis.

    Science.gov (United States)

    Morais, Sofia; Pratoomyot, Jarunan; Taggart, John B; Bron, James E; Guy, Derrick R; Bell, J Gordon; Tocher, Douglas R

    2011-05-20

    Expansion of aquaculture is seriously limited by reductions in fish oil (FO) supply for aquafeeds. Terrestrial alternatives such as vegetable oils (VO) have been investigated and recently a strategy combining genetic selection with changes in diet formulations has been proposed to meet growing demands for aquaculture products. This study investigates the influence of genotype on transcriptomic responses to sustainable feeds in Atlantic salmon. A microarray analysis was performed to investigate the liver transcriptome of two family groups selected according to their estimated breeding values (EBVs) for flesh lipid content, 'Lean' or 'Fat', fed diets containing either FO or a VO blend. Diet principally affected metabolism genes, mainly of lipid and carbohydrate, followed by immune response genes. Genotype had a much lower impact on metabolism-related genes and affected mostly signalling pathways. Replacement of dietary FO by VO caused an up-regulation of long-chain polyunsaturated fatty acid biosynthesis, but there was a clear genotype effect as fatty acyl elongase (elovl2) was only up-regulated and desaturases (Δ5 fad and Δ6 fad) showed a higher magnitude of response in Lean fish, which was reflected in liver fatty acid composition. Fatty acid synthase (FAS) was also up-regulated by VO and the effect was independent of genotype. Genetic background of the fish clearly affected regulation of lipid metabolism, as PPARα and PPARβ were down-regulated by the VO diet only in Lean fish, while in Fat salmon SREBP-1 expression was up-regulated by VO. In addition, all three genes had a lower expression in the Lean family group than in the Fat, when fed VO. Differences in muscle adiposity between family groups may have been caused by higher levels of hepatic fatty acid and glycerophospholipid synthesis in the Fat fish, as indicated by the expression of FAS, 1-acyl-sn-glycerol-3-phosphate acyltransferase and lipid phosphate phosphohydrolase 2. This study has identified metabolic pathways and key regulators that may respond differently to alternative plant-based feeds depending on genotype. Further studies are required but data suggest that it will be possible to identify families better adapted to alternative diet formulations that might be appropriate for future genetic selection programmes.

  1. Genotype-specific responses in Atlantic salmon (Salmo salar subject to dietary fish oil replacement by vegetable oil: a liver transcriptomic analysis

    Directory of Open Access Journals (Sweden)

    Guy Derrick R

    2011-05-01

    Full Text Available Abstract Background Expansion of aquaculture is seriously limited by reductions in fish oil (FO supply for aquafeeds. Terrestrial alternatives such as vegetable oils (VO have been investigated and recently a strategy combining genetic selection with changes in diet formulations has been proposed to meet growing demands for aquaculture products. This study investigates the influence of genotype on transcriptomic responses to sustainable feeds in Atlantic salmon. Results A microarray analysis was performed to investigate the liver transcriptome of two family groups selected according to their estimated breeding values (EBVs for flesh lipid content, 'Lean' or 'Fat', fed diets containing either FO or a VO blend. Diet principally affected metabolism genes, mainly of lipid and carbohydrate, followed by immune response genes. Genotype had a much lower impact on metabolism-related genes and affected mostly signalling pathways. Replacement of dietary FO by VO caused an up-regulation of long-chain polyunsaturated fatty acid biosynthesis, but there was a clear genotype effect as fatty acyl elongase (elovl2 was only up-regulated and desaturases (Δ5 fad and Δ6 fad showed a higher magnitude of response in Lean fish, which was reflected in liver fatty acid composition. Fatty acid synthase (FAS was also up-regulated by VO and the effect was independent of genotype. Genetic background of the fish clearly affected regulation of lipid metabolism, as PPARα and PPARβ were down-regulated by the VO diet only in Lean fish, while in Fat salmon SREBP-1 expression was up-regulated by VO. In addition, all three genes had a lower expression in the Lean family group than in the Fat, when fed VO. Differences in muscle adiposity between family groups may have been caused by higher levels of hepatic fatty acid and glycerophospholipid synthesis in the Fat fish, as indicated by the expression of FAS, 1-acyl-sn-glycerol-3-phosphate acyltransferase and lipid phosphate phosphohydrolase 2. Conclusions This study has identified metabolic pathways and key regulators that may respond differently to alternative plant-based feeds depending on genotype. Further studies are required but data suggest that it will be possible to identify families better adapted to alternative diet formulations that might be appropriate for future genetic selection programmes.

  2. Norsk fiskeriforvaltning og bærekraft; en studie av forvaltningen av atlantisk laks (Salmo salar) og nordøstarktisk torsk (Gadus morhua)

    OpenAIRE

    Meaas, Anne Christine

    2012-01-01

    Laksefisket og torskefisket er forvaltet av to forskjellige sektorer, og laksefisket er i tillegg sektorovergripende på grunn av laksens anadrome livshistorie. Denne oppgaven har tatt for seg disse to forvaltningene, og sett på disse i lys av bærekraftbegrepet. Resultatene ble funnet gjennom litteraturstudier og personlig kommunikasjon med personer i forvaltningen. Lakseforvaltningen har høy sosial bærekraft, og laksefisket har et stort potensial som mål for turister og fritidsfiskere. Lak...

  3. Piscine reovirus, but not Jaundice Syndrome, was transmissible to Chinook Salmon, Oncorhynchus tshawytscha (Walbaum), Sockeye Salmon, Oncorhynchus nerka (Walbaum), and Atlantic Salmon, Salmo salar L.

    Science.gov (United States)

    Garver, Kyle A.; Marty, Gary D.; Cockburn, Sarah N.; Richard, Jon; Hawley, Laura M.; Müller, Anita; Thompson, Rachel L.; Purcell, Maureen K.; Saksida, Sonja M.

    2015-01-01

    A Jaundice Syndrome occurs sporadically among sea-pen-farmed Chinook Salmon in British Columbia, the westernmost province of Canada. Affected salmon are easily identified by a distinctive yellow discolouration of the abdominal and periorbital regions. Through traditional diagnostics, no bacterial or viral agents were cultured from tissues of jaundiced Chinook Salmon; however, piscine reovirus (PRV) was identified via RT-rPCR in all 10 affected fish sampled. By histopathology, Jaundice Syndrome is an acute to peracute systemic disease, and the time from first clinical signs to death is likely Salmon, Sockeye Salmon and Atlantic Salmon, intraperitoneally inoculated with a PRV-positive organ homogenate from jaundiced Chinook Salmon, developed no gross or microscopic evidence of jaundice despite persistence of PRV for the 5-month holding period. The results from this study demonstrate that the Jaundice Syndrome was not transmissible by injection of material from infected fish and that PRV was not the sole aetiological factor for the condition. Additionally, these findings showed the Pacific coast strain of PRV, while transmissible, was of low pathogenicity for Atlantic Salmon, Chinook Salmon and Sockeye Salmon.

  4. Efficacy of the treatments used for the control of Caligus rogercresseyi infecting Atlantic salmon, Salmo salar L., in a new fish-farming location in Region XI, Chile.

    Science.gov (United States)

    Bravo, S; Nuñez, M; Silva, M T

    2013-03-01

    Caligus rogercresseyi is the most important parasite affecting Atlantic salmon and rainbow trout farming in sea water in Chile. After the outbreaks of the infectious salmon anaemia recorded in Region X from 2007, the salmon industry has expanded southwards to Region XI, where 60% of Atlantic salmon in Chile is now produced. In parallel with the relocation of salmon production, sea lice infestation has also spread to Region XI, and today C. rogercresseyi is the most serious threat to the salmon-farming industry in this region. The results obtained through a year of monitoring between September 2007 and August 2008 on a farm located in the 'Las Guaitecas Archipelago' in Region XI (44°S; 74°W) showed that treatments with emamectin benzoate and deltamethrin did not give the expected control of Caligus. Failures of the treatments were associated with the loss of sensitivity recorded for C. rogercresseyi to emamectin benzoate in Region X. In addition, a major influence was the lack of delousing coordination measures with the neighbouring farms sharing the same area in that period. © 2013 Blackwell Publishing Ltd.

  5. Disease resistance in Atlantic salmon (Salmo salar: coinfection of the intracellular bacterial pathogen Piscirickettsia salmonis and the sea louse Caligus rogercresseyi.

    Directory of Open Access Journals (Sweden)

    Jean Paul Lhorente

    Full Text Available BACKGROUND: Naturally occurring coinfections of pathogens have been reported in salmonids, but their consequences on disease resistance are unclear. We hypothesized that 1 coinfection of Caligus rogercresseyi reduces the resistance of Atlantic salmon to Piscirickettsia salmonis; and 2 coinfection resistance is a heritable trait that does not correlate with resistance to a single infection. METHODOLOGY: In total, 1,634 pedigreed Atlantic salmon were exposed to a single infection (SI of P. salmonis (primary pathogen or coinfection with C. rogercresseyi (secondary pathogen. Low and high level of coinfection were evaluated (LC = 44 copepodites per fish; HC = 88 copepodites per fish. Survival and quantitative genetic analyses were performed to determine the resistance to the single infection and coinfections. MAIN FINDINGS: C. rogercresseyi significantly increased the mortality in fish infected with P. salmonis (SI mortality = 251/545; LC mortality = 544/544 and HC mortality = 545/545. Heritability estimates for resistance to P. salmonis were similar and of medium magnitude in all treatments (h2SI = 0.23 ± 0.07; h2LC = 0.17 ± 0.08; h2HC = 0.24 ± 0.07. A large and significant genetic correlation with regard to resistance was observed between coinfection treatments (rg LC-HC = 0.99 ± 0.01 but not between the single and coinfection treatments (rg SI-LC = -0.14 ± 0.33; rg SI-HC = 0.32 ± 0.34. CONCLUSIONS/SIGNIFICANCE: C. rogercresseyi, as a secondary pathogen, reduces the resistance of Atlantic salmon to the pathogen P. salmonis. Resistance to coinfection of Piscirickettsia salmonis and Caligus rogercresseyi in Atlantic salmon is a heritable trait. The absence of a genetic correlation between resistance to a single infection and resistance to coinfection indicates that different genes control these processes. Coinfection of different pathogens and resistance to coinfection needs to be considered in future research on salmon farming, selective breeding and conservation.

  6. The use of genomic information increases the accuracy of breeding value predictions for sea louse (Caligus rogercresseyi) resistance in Atlantic salmon (Salmo salar).

    Science.gov (United States)

    Correa, Katharina; Bangera, Rama; Figueroa, René; Lhorente, Jean P; Yáñez, José M

    2017-01-31

    Sea lice infestations caused by Caligus rogercresseyi are a main concern to the salmon farming industry due to associated economic losses. Resistance to this parasite was shown to have low to moderate genetic variation and its genetic architecture was suggested to be polygenic. The aim of this study was to compare accuracies of breeding value predictions obtained with pedigree-based best linear unbiased prediction (P-BLUP) methodology against different genomic prediction approaches: genomic BLUP (G-BLUP), Bayesian Lasso, and Bayes C. To achieve this, 2404 individuals from 118 families were measured for C. rogercresseyi count after a challenge and genotyped using 37 K single nucleotide polymorphisms. Accuracies were assessed using fivefold cross-validation and SNP densities of 0.5, 1, 5, 10, 25 and 37 K. Accuracy of genomic predictions increased with increasing SNP density and was higher than pedigree-based BLUP predictions by up to 22%. Both Bayesian and G-BLUP methods can predict breeding values with higher accuracies than pedigree-based BLUP, however, G-BLUP may be the preferred method because of reduced computation time and ease of implementation. A relatively low marker density (i.e. 10 K) is sufficient for maximal increase in accuracy when using G-BLUP or Bayesian methods for genomic prediction of C. rogercresseyi resistance in Atlantic salmon.

  7. Disease resistance in Atlantic salmon (Salmo salar): coinfection of the intracellular bacterial pathogen Piscirickettsia salmonis and the sea louse Caligus rogercresseyi.

    Science.gov (United States)

    Lhorente, Jean Paul; Gallardo, José A; Villanueva, Beatriz; Carabaño, María J; Neira, Roberto

    2014-01-01

    Naturally occurring coinfections of pathogens have been reported in salmonids, but their consequences on disease resistance are unclear. We hypothesized that 1) coinfection of Caligus rogercresseyi reduces the resistance of Atlantic salmon to Piscirickettsia salmonis; and 2) coinfection resistance is a heritable trait that does not correlate with resistance to a single infection. In total, 1,634 pedigreed Atlantic salmon were exposed to a single infection (SI) of P. salmonis (primary pathogen) or coinfection with C. rogercresseyi (secondary pathogen). Low and high level of coinfection were evaluated (LC = 44 copepodites per fish; HC = 88 copepodites per fish). Survival and quantitative genetic analyses were performed to determine the resistance to the single infection and coinfections. C. rogercresseyi significantly increased the mortality in fish infected with P. salmonis (SI mortality = 251/545; LC mortality = 544/544 and HC mortality = 545/545). Heritability estimates for resistance to P. salmonis were similar and of medium magnitude in all treatments (h2SI = 0.23 ± 0.07; h2LC = 0.17 ± 0.08; h2HC = 0.24 ± 0.07). A large and significant genetic correlation with regard to resistance was observed between coinfection treatments (rg LC-HC = 0.99 ± 0.01) but not between the single and coinfection treatments (rg SI-LC = -0.14 ± 0.33; rg SI-HC = 0.32 ± 0.34). C. rogercresseyi, as a secondary pathogen, reduces the resistance of Atlantic salmon to the pathogen P. salmonis. Resistance to coinfection of Piscirickettsia salmonis and Caligus rogercresseyi in Atlantic salmon is a heritable trait. The absence of a genetic correlation between resistance to a single infection and resistance to coinfection indicates that different genes control these processes. Coinfection of different pathogens and resistance to coinfection needs to be considered in future research on salmon farming, selective breeding and conservation.

  8. No influence of oxygen levels on pathogenesis and virus shedding in Salmonid alphavirus (SAV-challenged Atlantic salmon (Salmo salar L.

    Directory of Open Access Journals (Sweden)

    Andersen Linda

    2010-08-01

    Full Text Available Abstract Background For more than three decades, diseases caused by salmonid alphaviruses (SAV have become a major problem of increasing economic importance in the European fish-farming industry. However, experimental infection trials with SAV result in low or no mortality i.e very different from most field outbreaks of pancreas disease (PD. This probably reflects the difficulties in reproducing complex biotic and abiotic field conditions in the laboratory. In this study we looked at the relationship between SAV-infection in salmon and sub-lethal environmental hypoxia as a result of reduced flow-through in tank systems. Results The experiment demonstrated that constant reduced oxygen levels (60-65% oxygen saturation: 6.5-7.0 mg/L did not significantly increase the severity or the progress of pancreas disease (PD. These conclusions are based upon assessments of a semi-quantitative histopathological lesion score system, morbidities/mortalities, and levels of SAV RNA in tissues and water (measured by 1 MDS electropositive virus filters and downstream real-time RT-PCR. Furthermore, we demonstrate that the fish population shed detectable levels of the virus into the surrounding water during viraemia; 4-13 days after i.p. infection, and prior to appearance of severe lesions in heart (21-35 dpi. After this period, viral RNA from SAV could not be detected in water samples although still present in tissues (gills and hearts at lasting low levels. Lesions could be seen in exocrine pancreas at 7-21 days post infection, but no muscle lesions were seen. Conclusions In our study, experimentally induced hypoxia failed to explain the discrepancy between the severities reported from field outbreaks of SAV-disease and experimental infections. Reduction of oxygen levels to constant suboptimal levels had no effect on the severity of lesions caused by SAV-infection or the progress of the disease. Furthermore, we present a modified VIRADEL method which can be used to detect virus in water and to supplement experimental infection trials with information related to viral shedding. By using this method, we were able to demonstrate for the first time that shedding of SAV from the fish population into the surrounding water coincides with viraemia.

  9. In vitro adaptation of SAV3 in cell culture correlates with reduced in vivo replication capacity and virulence to Atlantic salmon (Salmo salar L.) parr.

    Science.gov (United States)

    Petterson, Elin; Guo, Tz-Chun; Evensen, Øystein; Haugland, Øyvind; Mikalsen, Aase B

    2015-10-01

    Salmonid alphavirus (SAV) is the causative agent of pancreas disease affecting Atlantic salmon and rainbow trout and causes a major burden to the aquaculture industry. This study describes a Norwegian subtype SAV3 virus isolate (SAV3-H10) subjected to serial passages in Chinook salmon embryo cells (CHSE-214) followed by Asian Grouper skin cells (AGK). Two passages from CHSE and one after transfer to AGK cells were chosen for further investigation, based on variation in degree and development of cytopathic effect (CPE). After plaque purification, several in vitro studies were performed. Cell viability after infection, viral replication and ability to cause morphological changes in CHSE and AGK cells was studied for the three isolates. The AGK-transferred isolate was identified with the strongest abilities to reduce cell viability, replicate more and cause more CPE in cell culture when compared with the early and late CHSE-grown isolates. Subsequently, the isolates were tested in an experimental fish challenge, showing higher viral load and higher pathological score for the least cell-cultured isolate. Full-length sequencing of the viral genome of the three isolates revealed divergence in four amino acid positions and the AGK-grown isolate also had a 3 nt deletion in the 3'UTR. In conclusion, we show that cell culture of SAV3-H10 selects for strains inducing earlier CPE in vitro with increased viral replication. In vivo, the effect is reversed, with lower replication levels and lower pathology scores in target organs. This study outlines a path to identify potential virulence motifs of SAV3.

  10. The interbranchial lymphoid tissue of Atlantic Salmon (Salmo salar L) extends as a diffuse mucosal lymphoid tissue throughout the trailing edge of the gill filament

    DEFF Research Database (Denmark)

    Dalum, Alf S; Austbø, Lars; Bjørgen, Håvard

    2015-01-01

    in all gill segments investigated. Numerous major histocompatibility complex class II(+) -cells were distributed uniformly throughout the filament epithelial tissue. Few Ig(+) -cells were detected. Overall, the morphological features and comparable immune gene expression of the previously described ILT......The teleost gill forms an extensive, semipermeable barrier that must tolerate intimate contact with the surrounding environment and be able to protect the body from external pathogens. The recent discovery of the interbranchial lymphoid tissue (ILT) has initiated an anatomical and functional...... investigation of the lymphoid tissue of the salmonid gill. In this article, sectioning of gill arches in all three primary planes revealed an elongation of the ILT outward along the trailing edge of the primary filament to the very distal end, a finding not previously described. This newly found lymphoid tissue...

  11. Superior protection conferred by inactivated whole virus vaccine over subunit and DNA vaccines against salmonid alphavirus infection in Atlantic salmon (Salmo salar L.).

    Science.gov (United States)

    Xu, Cheng; Mutoloki, Stephen; Evensen, Øystein

    2012-06-06

    Salmonid alphavirus 3 (SAV-3) is an emerging pathogen in Norwegian salmon farming and causes severe annual losses. We studied the immunogenicity and protective ability of subunit and DNA vaccines based on E1 and E2 spike proteins of salmonid alphavirus subtype 3 (SAV-3), and compared these to an experimental inactivated, whole virus (IWV) vaccine in Atlantic salmon. The antigens were delivered as water-in-oil emulsions for the subunit and inactivated vaccines and non-formulated for the DNA vaccines. The IWV and the E2 subunit prime-boost groups had circulating neutralizing antibodies at challenge, correlating with high protection against lethal challenge and 3-log(10) reduction of virus titer in heart for the IWV group. Prime-boost with E1 subunit vaccine also conferred significant protection against mortality, but did not correlate with neutralizing antibody levels. Protection against pathology in internal organs was only seen for the IWV group. Prime-boost with E1 and E2 DNA vaccines showed marginal protection in terms of reduction of viral replication in target organs and protection against mortality was not different from controls. The IWV group showed significant upregulation of IFNγ and IL2 mRNA expression at 4 weeks post challenge possibly indicating that other mechanisms in addition to antibody responses play a role in mediating protection against infection. This is the first report comparing the immunogenicity and protection against mortality for IWV vaccines and spike protein subunit and DNA vaccines against salmonid alphavirus infection in Atlantic salmon. The IWV vaccine has superior immunogenicity over sub-unit and DNA vaccines. Copyright © 2012 Elsevier Ltd. All rights reserved.

  12. Peptide-binding motif prediction by using phage display library for SasaUBA*0301, a resistance haplotype of MHC class I molecule from Atlantic Salmon (Salmo salar)

    DEFF Research Database (Denmark)

    Zhao, Heng; Hermsen, Trudi; Stet, Rene J M

    2008-01-01

    class I molecule might have a very similar binding motif at the C-terminus compared with a known mouse class I molecule H2-Kb which has L, or I, V, M at p8. Previous work showed that Atlantic Salmon carrying the allele SasaUBA*0301 are resistant to infectious Salmon aneamia virus......The structure of the peptide-binding specificity of major histocompatibility complex (MHC) class I has been analyzed extensively in human and mouse. For fish, there are no crystallographic models of MHC molecules, neither are there data on the peptide-binding specificity. In this study, we describe...... for the first time the identification of a fish class I peptide-MHC ligand binding motif. Phage display technology using both 7mer and 12mer libraries enabled us to identify peptide ligands with unique specificity that interacts with the recombinant Salmon MHC class I molecule. The recombinant proteins, beta(2...

  13. Hepatic in vitro toxicity assessment of PBDE congeners BDE47, BDE153 and BDE154 in Atlantic salmon (Salmo salar L.)

    Energy Technology Data Exchange (ETDEWEB)

    Softeland, Liv, E-mail: lso@nifes.no [National Institute of Nutrition and Seafood Research, PO Box 2029 Nordnes, N-5817 Bergen (Norway); Petersen, Kjell [Computational Biology Unit, Bergen Centre for Computational Science, Uni Research AS, Thormohlensgt 55, N5008 Bergen (Norway); Stavrum, Anne-Kristin [Dept of Clinical Medicine, University of Bergen (Norway); Wu, Terence [Yale University W.M. Keck Biotechnology Resource, 300 George St., Room G001, New Haven, CT 06511 (United States); Olsvik, Pal A. [National Institute of Nutrition and Seafood Research, PO Box 2029 Nordnes, N-5817 Bergen (Norway)

    2011-10-15

    The brominated flame retardant congeners BDE47, BDE153 and BDE154 are among the congeners accumulating to the highest degree in fish. In order to gain knowledge about the toxicological effects of PBDEs in fish, microarray-based transcriptomic and 2D-DIGE/MALDI-TOF/TOF proteomic approaches were used to screen for effects in primary Atlantic salmon hepatocytes exposed to these congeners alone or in combination (PBDE-MIX). A small set of stress related transcripts and proteins were differentially expressed in the PBDE exposed hepatocytes. The PBDE-MIX, and BDE153 to a lesser degree, seems to have induced metabolic disturbances by affecting several pathways related to glucose homeostasis. Further, effects on cell cycle control and proliferation signal pathways in PBDE-MIX-exposed hepatocytes clearly suggest that the PBDE exposure affected cell proliferation processes. CYP1A was 7.41- and 7.37-fold up-regulated in hepatocytes exposed to BDE47 and PBDE-MIX, respectively, and was the only biotransformation pathway affected by the PBDE exposure. The factorial design and PLS regression analyses of the effect of the PBDE-MIX indicated that BDE47 contributed the most to the observed CYP1A response, suggesting that this congener should be incorporated in the toxic equivalent (TEQ) concept in future risk assessment of dioxin-like chemicals. Additionally, a significant up-regulation of the ER-responsive genes VTG and ZP3 was observed in cells exposed to BDE47 and PBDE-MIX. Further analyses suggested that BDE47 and BDE154 have an estrogenic effect in male fish. The data also suggested an antagonistic interaction between BDE153 and BDE154. In conclusion, this study shows that PBDEs can affect several biological systems in Atlantic salmon cells, and demonstrates the need for more studies on the simultaneous exposure to chemical mixtures to identify combined effects of chemicals.

  14. Acquired protective immunity in Atlantic salmon Salmo salar against the myxozoan, Kudoa thyrsites, involves induction of MHIIβ(+)/CD83(+) antigen presenting cells.

    Science.gov (United States)

    Braden, Laura M; Rasmussen, Karina J; Purcell, Sara L; Ellis, Lauren; Mahony, Amelia; Cho, Steven; Whyte, Shona K; Jones, Simon R M; Fast, Mark D

    2017-10-09

    The histozoic myxozoan parasite Kudoa thyrsites causes post-mortem myoliquefaction and is responsible for economic losses to salmon aquaculture in the Pacific Northwest. Despite its importance, little is known about the host-parasite relationship, including the host response to infection. The present work sought to characterize the immune response in Atlantic salmon during infection, recovery and re-exposure to K. thyrsites After exposure to infective seawater, infected and uninfected smolts were sampled three times over 4275 degree-days. Histological analysis revealed infection severity decreased over time in exposed fish while in controls there was no evidence of infection. Following a secondary exposure of all fish, severity of infection in the controls was similar to that measured in exposed fish at the first sampling time, but was significantly reduced in re-exposed fish, suggesting the acquisition of protective immunity. Using immunohistochemistry, we detected a population of MHIIβ(+) cells in infected muscle that followed a pattern of abundance concordant with parasite prevalence. Infiltration of these cells into infected myocytes preceded destruction of the plasmodium and dissemination of myxospores. Dual-labelling indicated a majority of these cells were CD83(+)/MHIIβ(+) Using RT-qPCR, we detected significant induction of cellular effectors including macrophage/dendritic cells (mhii/cd83/mcsf), B cells (igm/igt), and cytotoxic T cells (cd8/nkl) in the musculature of infected fish. These data support a role for cellular effectors such as antigen presenting cells (monocyte/macrophage and dendritic cells) along with B and T cells in the acquired protective immune response of Atlantic salmon against K. thyrsites. Copyright © 2017 American Society for Microbiology.

  15. Molecular and immunohistochemical studies on epidermal responses in Atlantic salmon Salmo salar L. induced by Gyrodactylus salaris Malmberg, 1957

    DEFF Research Database (Denmark)

    Kania, Per Walter; Evensen, O.; Larsen, Thomas Bjerre

    2010-01-01

    salmon, and IL-10 may play a role in this regard. It can be hypothesized that resistant salmon regulate the parasite population by restricting nutrients (sloughed epithelial cells and associated material) and thereby starve the parasites. In association with this ‘scorchedearth strategy’, the production...... experiments. Highly susceptible East Atlantic salmon allowed parasite populations to reach up to 3000 parasites per host within 6 weeks, whereas less susceptible Baltic salmon never reached larger parasite burdens than 122 parasites per host during the same period. The present study, comprising...... of pathogen-binding effector molecules such as serum amyloid A (SAA) (or others still not detected) may contribute to the resistance status of the fish during the later infection phases....

  16. Assessing the impact of swimming exercise and the relative susceptibility of rainbow trout oncorhynchus mykiss (walbaum) and atlantic salmon salmo salar L. following injection challenge with weissella ceti

    Science.gov (United States)

    All-female rainbow trout and mixed-sex Atlantic salmon (approximately 200 g and 120 g initial weight, respectively) were maintained in small circular tanks in a flow-through system under study conditions for a period of five months. The four tank populations consisted of rainbow trout exposed to ei...

  17. Angiotensin I-Converting Enzyme (ACE Inhibitory Activity and ACE Inhibitory Peptides of Salmon (Salmo salar Protein Hydrolysates Obtained by Human and Porcine Gastrointestinal Enzymes

    Directory of Open Access Journals (Sweden)

    Małgorzata Darewicz

    2014-08-01

    Full Text Available The objectives of the present study were two-fold: first, to detect whether salmon protein fractions possess angiotensin I-converting enzyme (ACE inhibitory properties and whether salmon proteins can release ACE inhibitory peptides during a sequential in vitro hydrolysis (with commercial porcine enzymes and ex vivo digestion (with human gastrointestinal enzymes. Secondly, to evaluate the ACE inhibitory activity of generated hydrolysates. A two-step ex vivo and in vitro model digestion was performed to simulate the human digestion process. Salmon proteins were degraded more efficiently by porcine enzymes than by human gastrointestinal juices and sarcoplasmic proteins were digested/hydrolyzed more easily than myofibrillar proteins. The ex vivo digested myofibrillar and sarcoplasmic duodenal samples showed IC50 values (concentration required to decrease the ACE activity by 50% of 1.06 and 2.16 mg/mL, respectively. The in vitro hydrolyzed myofibrillar and sarcoplasmic samples showed IC50 values of 0.91 and 1.04 mg/mL, respectively. Based on the results of in silico studies, it was possible to identify 9 peptides of the ex vivo hydrolysates and 7 peptides of the in vitro hydrolysates of salmon proteins of 11 selected peptides. In both types of salmon hydrolysates, ACE-inhibitory peptides IW, IY, TVY and VW were identified. In the in vitro salmon protein hydrolysates an ACE-inhibitory peptides VPW and VY were also detected, while ACE-inhibitory peptides ALPHA, IVY and IWHHT were identified in the hydrolysates generated with ex vivo digestion. In our studies, we documented ACE inhibitory in vitro effects of salmon protein hydrolysates obtained by human and as well as porcine gastrointestinal enzymes.

  18. 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

    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...

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

    Science.gov (United States)

    2013-01-01

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

  20. A comparison of gene transcription profiles of domesticated and wild Atlantic salmon (Salmo salar L.) at early life stages, reared under controlled conditions.

    Science.gov (United States)

    Bicskei, Beatrix; Bron, James E; Glover, Kevin A; Taggart, John B

    2014-10-09

    Atlantic salmon have been subject to domestication for approximately ten generations, beginning in the early 1970s. This process of artificial selection will have created various genetic differences between wild and farmed stocks. Each year, hundreds of thousands of farmed fish escape into the wild. These escapees may interbreed with wild conspecifics raising concerns for both the fish-farming industry and fisheries managers. Thus, a better understanding of the interactions between domesticated and wild salmon is essential to the continued sustainability of the aquaculture industry and to the maintenance of healthy wild stocks. We compared the transcriptomes of a wild Norwegian Atlantic salmon population (Figgjo) and a Norwegian farmed strain (Mowi) at two life stages: yolk sac fry and post first-feeding fry. The analysis employed 44 k oligo-microarrays to analyse gene expression of 36 farmed, wild and hybrid (farmed dam x wild sire) individuals reared under identical hatchery conditions. Although some of the transcriptional differences detected overlapped between sampling points, our results highlighted the importance of studying various life stages. Compared to the wild population, the Mowi strain displayed up-regulation in mRNA translation-related and down regulation in nervous and immune system -related pathways in the sac fry, whereas up-regulation of digestive and endocrine activities, carbohydrate, energy, amino acid and lipid metabolism and down-regulation of environmental information processing and immune system pathways were evident in the feeding fry. Differentially regulated pathways that were common among life stages generally belonged to environmental information processing and immune system functional groups. In addition, we found indications of strong maternal effects, reinforcing the importance of including reciprocal hybrids in the analysis. In agreement with previous studies we showed that domestication has caused changes in the transcriptome of wild Atlantic salmon and that many of the affected pathways are life-stage specific We highlighted the importance of reciprocal hybrids to the deconvolution of maternal/paternal effects and our data support the view that the genetic architecture of the strains studied highly influences the genes differentially expressed between wild and domesticated fish.

  1. Reduced total hardness of fresh water enhances the efficacy of bathing as a treatment for amoebic gill disease in Atlantic salmon, Salmo salar L.

    Science.gov (United States)

    Roberts, S D; Powell, M D

    2003-10-01

    The current treatment for amoebic gill disease (AGD)-affected Atlantic salmon involves bathing sea-caged fish in fresh water, often sourced from local dams, for 3-4 h. In both a small-scale laboratory and an on-farm field experiment, the effects of water hardness on the efficacy of freshwater bathing were assessed. Results showed that soft fresh water (19.3-37.4 mg L(-1) CaCO3), whether it be naturally soft city mains water or artificially softened dam water, was more efficacious at alleviating AGD in affected fish than hard fresh water (173-236.3 mg L(-1) CaCO3). Soft freshwater bathing significantly reduced viable gill amoebae numbers (from 73.9 to 40.9% of total count) and significantly alleviated gill pathology, both gross and histological. Following bathing, gross gill pathological scores of soft freshwater bathed fish lagged 2 weeks behind hard freshwater bathed fish. Significant gill lesion fragmentation, and shedding of lesion-associated hyperplastic tissue, was accompanied by a significant reduction in AGD-affected gill filaments in soft freshwater bathed fish. Furthermore, soft freshwater bathing alleviated the blood plasma electrolyte imbalance seen in control (sea water) and hard freshwater bathed fish. This study showed that the use of soft fresh water for bathing AGD-affected Atlantic salmon could be an improvement to the current method of treatment. Not only does it reduce gill amoeba numbers, but also, it is of a therapeutic advantage with the potential to reduce bathing frequency.

  2. Modulation of selenium tissue distribution and selenoprotein expression in Atlantic salmon (Salmo salar L.) fed diets with graded levels of plant ingredients.

    Science.gov (United States)

    Betancor, Monica B; Dam, Thi M C; Walton, James; Morken, Thea; Campbell, Patrick J; Tocher, Douglas R

    2016-04-01

    Increased substitution of marine ingredients by terrestrial plant products in aquafeeds has been proven to be suitable for Atlantic salmon farming. However, a reduction in n-3 long-chain PUFA is a consequence of this substitution. In contrast, relatively little attention has been paid to the effects of fishmeal and oil substitution on levels of micronutrients such as Se, considering fish are major sources of this mineral for human consumers. To evaluate the effects of dietary marine ingredient substitution on tissue Se distribution and the expression of Se metabolism and antioxidant enzyme genes, Atlantic salmons were fed three feeds based on commercial formulations with increasing levels of plant proteins (PP) and vegetable oil. Lipid content in flesh did not vary at any sampling point, but it was higher in the liver of 1 kg of fish fed higher PP. Fatty acid content reflected dietary input and was related to oxidation levels (thiobarbituric acid-reactive substances). Liver had the highest Se levels, followed by head kidney, whereas the lowest contents were found in brain and gill. The Se concentration of flesh decreased considerably with high levels of substitution, reducing the added value of fish consumption. Only the brain showed significant differences in glutathione peroxidase, transfer RNA selenocysteine 1-associated protein 1b and superoxide dismutase expression, whereas no significant regulation of Se-related genes was found in liver. Although Se levels in the diets satisfied the essential requirements of salmon, high PP levels led to a reduction in the supply of this essential micronutrient.

  3. Comparing the transcriptomes of embryos from domesticated and wild Atlantic salmon (Salmo salar L.) stocks and examining factors that influence heritability of gene expression.

    Science.gov (United States)

    Bicskei, Beatrix; Taggart, John B; Glover, Kevin A; Bron, James E

    2016-03-17

    Due to selective breeding, domesticated and wild Atlantic salmon are genetically diverged, which raises concerns about farmed escapees having the potential to alter the genetic composition of wild populations and thereby disrupting local adaptation. Documenting transcriptional differences between wild and domesticated stocks under controlled conditions is one way to explore the consequences of domestication and selection. We compared the transcriptomes of wild and domesticated Atlantic salmon embryos, by using a custom 44k oligonucleotide microarray to identify perturbed gene pathways between the two stocks, and to document the inheritance patterns of differentially-expressed genes by examining gene expression in their reciprocal hybrids. Data from 24 array interrogations were analysed: four reciprocal cross types (W♀ × W♂, D♀ × W♂; W♀ × D♂, D♀ × D♂) × six biological replicates. A common set of 31,491 features on the microarrays passed quality control, of which about 62 % were assigned a KEGG Orthology number. A total of 6037 distinct genes were identified for gene-set enrichment/pathway analysis. The most highly enriched functional groups that were perturbed between the two stocks were cellular signalling and immune system, ribosome and RNA transport, and focal adhesion and gap junction pathways, relating to cell communication and cell adhesion molecules. Most transcripts that were differentially expressed between the stocks were governed by additive gene interaction (33 to 42 %). Maternal dominance and over-dominance were also prevalent modes of inheritance, with no convincing evidence for a stock effect. Our data indicate that even at this relatively early developmental stage, transcriptional differences exist between the two stocks and affect pathways that are relevant to wild versus domesticated environments. Many of the identified differentially perturbed pathways are involved in organogenesis, which is expected to be an active process at the eyed egg stage. The dominant effects are more largely due to the maternal line than to the origin of the stock. This finding is particularly relevant in the context of potential introgression between farmed and wild fish, since female escapees tend to have a higher spawning success rate compared to males.

  4. Omega-3 and alpha-tocopherol provide more protection against contaminants in novel feeds for Atlantic salmon (Salmo salar L.) than omega-6 and gamma tocopherol.

    Science.gov (United States)

    Søfteland, Liv; Berntssen, Marc H G; Kirwan, Jennifer A; Størseth, Trond R; Viant, Mark R; Torstensen, Bente E; Waagbø, Rune; Olsvik, Pål A

    2016-01-01

    Extended use of plant ingredients in Atlantic salmon farming has increased the need for knowledge on the effects of new nutrients and contaminants in plant based feeds on fish health and nutrient-contaminant interactions. Primary Atlantic salmon hepatocytes were exposed to a mixture of PAHs and pesticides alone or in combination with the nutrients ARA, EPA, α-tocopherol, and γ-tocopherol according to a factorial design. Cells were screened for effects using xCELLigence cytotoxicity screening, NMR spectroscopy metabolomics, mass spectrometry lipidomics and RT-qPCR transcriptomics. The cytotoxicity results suggest that adverse effects of the contaminants can be counteracted by the nutrients. The lipidomics suggested effects on cell membrane stability and vitamin D metabolism after contaminant and fatty acid exposure. Co-exposure of the contaminants with EPA or α-tocopherol contributed to an antagonistic effect in exposed cells, with reduced effects on the VTG and FABP4 transcripts. ARA and γ-tocopherol strengthened the contaminant-induced response, ARA by contributing to an additive and synergistic induction of CYP1A, CYP3A and CPT2, and γ-tocopherol by synergistically increasing ACOX1. Individually EPA and α-tocopherol seemed more beneficial than ARA and γ-tocopherol in preventing the adverse effects induced by the contaminant mixture, though a combination of all nutrients showed the greatest ameliorating effect.

  5. The efficacy of emamectin benzoate against infestations of Lepeophtheirus salmonis on farmed Atlantic salmon (Salmo salar L) in Scotland, 2002-2006.

    Science.gov (United States)

    Lees, Fiona; Baillie, Mark; Gettinby, George; Revie, Crawford W

    2008-02-06

    Infestations of the parasitic copepod Lepeophtheirus salmonis, commonly referred to as sea lice, represent a major challenge to commercial salmon aquaculture. Dependence on a limited number of theraputants to control such infestations has led to concerns of reduced sensitivity in some sea lice populations. This study investigates trends in the efficacy of the in-feed treatment emamectin benzoate in Scotland, the active ingredient most widely used across all salmon producing regions. Study data were drawn from over 50 commercial Atlantic salmon farms on the west coast of Scotland between 2002 and 2006. An epi-informatics approach was adopted whereby available farm records, descriptive epidemiological summaries and statistical linear modelling methods were used to identify factors that significantly affect sea lice abundance following treatment with emamectin benzoate (SLICE(R), Schering Plough Animal Health). The results show that although sea lice infestations are reduced following the application of emamectin benzoate, not all treatments are effective. Specifically there is evidence of variation across geographical regions and a reduction in efficacy over time. Reduced sensitivity and potential resistance to currently available medicines are constant threats to maintaining control of sea lice populations on Atlantic salmon farms. There is a need for on-going monitoring of emamectin benzoate treatment efficacy together with reasons for any apparent reduction in performance. In addition, strategic rotation of medicines should be encouraged and empirical evidence for the benefit of such strategies more fully evaluated.

  6. Omega-3 and alpha-tocopherol provide more protection against contaminants in novel feeds for Atlantic salmon (Salmo salar L. than omega-6 and gamma tocopherol

    Directory of Open Access Journals (Sweden)

    Liv Søfteland

    2016-01-01

    Full Text Available Extended use of plant ingredients in Atlantic salmon farming has increased the need for knowledge on the effects of new nutrients and contaminants in plant based feeds on fish health and nutrient-contaminant interactions. Primary Atlantic salmon hepatocytes were exposed to a mixture of PAHs and pesticides alone or in combination with the nutrients ARA, EPA, α-tocopherol, and γ-tocopherol according to a factorial design. Cells were screened for effects using xCELLigence cytotoxicity screening, NMR spectroscopy metabolomics, mass spectrometry lipidomics and RT-qPCR transcriptomics. The cytotoxicity results suggest that adverse effects of the contaminants can be counteracted by the nutrients. The lipidomics suggested effects on cell membrane stability and vitamin D metabolism after contaminant and fatty acid exposure. Co-exposure of the contaminants with EPA or α-tocopherol contributed to an antagonistic effect in exposed cells, with reduced effects on the VTG and FABP4 transcripts. ARA and γ-tocopherol strengthened the contaminant-induced response, ARA by contributing to an additive and synergistic induction of CYP1A, CYP3A and CPT2, and γ-tocopherol by synergistically increasing ACOX1. Individually EPA and α-tocopherol seemed more beneficial than ARA and γ-tocopherol in preventing the adverse effects induced by the contaminant mixture, though a combination of all nutrients showed the greatest ameliorating effect.

  7. Disturbance of the intestinal mucosal immune system of farmed Atlantic salmon (Salmo salar), in response to long-term hypoxic conditions.

    Science.gov (United States)

    Niklasson, L; Sundh, H; Fridell, F; Taranger, G L; Sundell, K

    2011-12-01

    The gastrointestinal (GI) tract has many important biological functions. One is to serve as a barrier between the fish and the external environment. A decreased physical barrier function of the intestine may lead to increased inflow of luminal content and subsequent activation of the intestinal mucosal immune system. This activation is governed by the ability of various compounds to induce cytokine release and immune cell activity, leading to an immune response. In mammals, the impact of stress on the intestinal barrier is well documented and results in increased intestinal permeability and thus increased stimulation of the mucosal immune system. Fish reared in sea cages may at times be exposed to unfavourable environmental conditions leading to chronic stress and disturbed intestinal integrity. This change in permeability may increase the exposure of the mucosal immune system to activating compounds. In the present study, the effect of a prolonged stress on the intestinal mucosal immune system of fish is therefore addressed. Atlantic salmon were exposed to low levels (50%) of dissolved oxygen (DO) for 6-7 weeks in consecutive experiments performed at 8 and 16 °C. Immune parameters were assessed in terms of mRNA expression of the key cytokines, interleukin-1β (IL-1β), IL-8, IL-10, interferon-γ (IFNγ) and transforming growth factor-β (TGFβ) as well as the immune regulatory inhibitor of nuclear factor κB (IκB). In the experiment at 8 °C also mucosal neutrophil infiltration was monitored. Subjecting the fish to low DO levels at 8 °C resulted in an increased mucosal neutrophil infiltration together with a down-regulation of IκB. At the higher temperature, 16 °C, low DO levels created decreased expression of the pro-inflammatory cytokine IL-1β in both intestinal regions as well as an increased expression of IL-10 in the proximal intestine. These results suggest that husbandry conditions in sea cages with DO levels as low as 50% clearly affects the intestinal mucosal immune system and results in a chronic inflammation. Moreover, the effects of low DO levels on the immune factors examined were more pronounced in the 16 °C experiment suggesting additive effects of high temperatures. Copyright © 2011 Elsevier Ltd. All rights reserved.

  8. Temporal change in genetic integrity suggests loss of local adaptation in a wild Atlantic salmon (Salmo salar) population following introgression by farmed escapees

    Science.gov (United States)

    Bourret, V; O'Reilly, P T; Carr, J W; Berg, P R; Bernatchez, L

    2011-01-01

    In some wild Atlantic salmon populations, rapid declines in numbers of wild returning adults has been associated with an increase in the prevalence of farmed salmon. Studies of phenotypic variation have shown that interbreeding between farmed and wild salmon may lead to loss of local adaptation. Yet, few studies have attempted to assess the impact of interbreeding at the genome level, especially among North American populations. Here, we document temporal changes in the genetic makeup of the severely threatened Magaguadavic River salmon population (Bay of Fundy, Canada), a population that might have been impacted by interbreeding with farmed salmon for nearly 20 years. Wild and farmed individuals caught entering the river from 1980 to 2005 were genotyped at 112 single-nucleotide polymorphisms (SNPs), and/or eight microsatellite loci, to scan for potential shifts in adaptive genetic variation. No significant temporal change in microsatellite-based estimates of allele richness or gene diversity was detected in the wild population, despite its precipitous decline in numbers over the last two decades. This might reflect the effect of introgression from farmed salmon, which was corroborated by temporal change in linkage-disequilibrium. Moreover, SNP genome scans identified a temporal decrease in candidate loci potentially under directional selection. Of particular interest was a SNP previously shown to be strongly associated with an important quantitative trait locus for parr mark number, which retained its genetic distinctiveness between farmed and wild fish longer than other outliers. Overall, these results indicate that farmed escapees have introgressed with wild Magaguadavic salmon resulting in significant alteration of the genetic integrity of the native population, including possible loss of adaptation to wild conditions. PMID:21224876

  9. Isolation and partial characterization of a novel paramyxovirus from the gills of diseased seawater-reared Atlantic salmon (Salmo salar L).

    Science.gov (United States)

    Kvellestad, Agnar; Dannevig, Birgit H; Falk, Knut

    2003-08-01

    A formerly undescribed virus has been isolated from the gills of farmed Atlantic salmon post-smolts in Norway suffering from gill disease. Cytopathic effects appeared in RTgill-W1 cells 9 weeks post-inoculation with gill tissue material. Virus production continued for an extended period thereafter. Light and electron microscopic examination revealed inclusions and replication in the cytoplasm. The viral nucleocapsid consisted of approximately 17 nm thick filaments in a herringbone pattern. Certain areas of the plasma membrane were thickened by the alignment of nucleocapsids on the internal surface and projections of 10 nm long viral glycoprotein spikes on the external surface. Virus assembly and release was achieved by budding through the modified plasma membrane. Negatively stained virions were spherical and partly pleomorphic with a diameter of 150-300 nm as seen by electron microscopy. The virus was sensitive to chloroform, heat and low and high pH, and replication was not inhibited by Br-dU or IdU indicating an RNA genome. Both haemagglutination and receptor-destroying enzyme activity were associated with the virions and the formation of syncytia in infected cultures indicated fusion activity. The receptor-destroying enzyme was identified as neuraminidase. The virus contained five major structural polypeptides with estimated molecular masses of 70, 62, 60, 48 and 37 kDa. Its buoyant density was 1.18-1.19 g ml(-1) in CsCl gradients. From the observed properties we conclude that this new virus belongs to the Paramyxoviridae and suggest the name Atlantic salmon paramyxovirus (ASPV). Furthermore, replication occurred at 6-21 degrees C, suggesting a host range confined to cold-blooded animals.

  10. Functional feeds reduce heart inflammation and pathology in Atlantic Salmon (Salmo salar L.) following experimental challenge with Atlantic salmon reovirus (ASRV).

    Science.gov (United States)

    Martinez-Rubio, Laura; Morais, Sofia; Evensen, Øystein; Wadsworth, Simon; Ruohonen, Kari; Vecino, Jose L G; Bell, J Gordon; Tocher, Douglas R

    2012-01-01

    Heart and Skeletal Muscle Inflammation (HSMI), recently associated with a novel Atlantic salmon reovirus (ASRV), is currently one of the most prevalent inflammatory diseases in commercial Atlantic salmon farms in Norway. Mortality varies from low to 20%, but morbidity can be very high, reducing growth performance and causing considerable financial impact. Clinical symptoms, including myocarditis, myocardial and red skeletal muscle necrosis, correlate with the intensity of the inflammatory response. In the present study, the effects of two functional feeds (FF1 and FF2) were compared to a standard commercial reference feed (ST) in Atlantic salmon subjected to an ASRV challenge. The functional feeds had reduced levels of total lipid and digestible energy, and different levels and proportions of long-chain polyunsaturated fatty acids (LC-PUFA). The objective was to determine whether these feeds could provide effective protection by decreasing the inflammatory response associated with HSMI. Histopathology, viral load, fatty acid composition and gene expression of heart tissue were assessed over a period of 16 weeks post-infection with ASRV. The viral load and histopathology scores in heart tissue in response to ASRV infection were reduced in fish fed both functional feeds, with FF1 showing the greatest effect. Microarray hierarchical cluster analysis showed that the functional feeds greatly affected expression of inflammation/immune related genes over the course of the ASRV infection. Viral load correlated with up-regulation of pro-inflammatory genes at the early-mid stages of infection in fish fed the ST diet. Expression of inflammatory genes 16-weeks after ASRV challenge reflected the difference in efficacy between the functional feeds, with fish fed FF1 showing lower expression. Thus, severity of the lesions in heart tissue correlated with the intensity of the innate immune response and was associated with tissue fatty acid compositions. The present study demonstrated that dietary modulation through clinical nutrition had major influences on the development and severity of the response to ASRV infection in salmon. Thus, HSMI was reduced in fish fed the functional feeds, particularly FF1. The modulation of gene expression between fish fed the different feeds provided further insight into the molecular mechanisms and progression of the inflammatory and immune responses to ASRV infection in salmon.

  11. The enzyme profiles in the connective tissue attaching pin bones to the surrounding tissue is specific in farmed salmon (Salmo salar) and cod (Gadus morhua L.).

    Science.gov (United States)

    Vuong, Tram T; Rønning, Sissel B; Kolset, Svein O; Pedersen, Mona E

    2017-02-01

    Post mortem storage is a necessary process for removal of pin bones without destruction of fillets, thereby avoiding volume and economic loss. However, the enzymes involved in loosening pin bones during storage have not been studied to a great extent. In this study, the activities and localization of MMPs in the connective tissue (CT) of pin bones dissected from fillet of salmon and cod were investigated. Interestingly, the enzyme activity profile in these two species was different during post mortem storage of fish fillets. Adding MMP inhibitor (GM6001) and serine protease inhibitor (Pefabloc) revealed different effects in the two species, suggesting different regulations in salmon and cod. In situ zymography with the same inhibitors verified MMP and serine protease activity in CT close to pin bone at early post mortem (6 h) in salmon. However, MMP inhibition was not evident in cod in this area at that time point. Immunohistochemistry further revealed MMP9 and MMP13 were located more to the outer rim of CT, facing the pin bone and adipose tissue, while MMP7 was more randomly distributed within CT in salmon. In contrast, all these three MMPs were randomly distributed in CT in cod. In summary, our study reveals different MMP enzyme profiles in salmon and cod in the pin bone area, influenced by serine proteases, and suggests that MMPs and serine proteases must be taken in consideration when studying the conditions for early pin bone removal.

  12. Comparative pathogenesis of piscirickettsiosis in Atlantic salmon (Salmo salar L.) post-smolt experimentally challenged with LF-89-like and EM-90-like Piscirickettsia salmonis isolates.

    Science.gov (United States)

    Rozas-Serri, M; Ildefonso, R; Peña, A; Enríquez, R; Barrientos, S; Maldonado, L

    2017-10-01

    Piscirickettsiosis (SRS) is the most prevalent bacterial disease in Chilean salmon aquaculture and is responsible for high economic losses. The aim of this study was to comparatively characterize the pathogenesis of SRS in post-smolt Atlantic salmon during the early and late stages of infection with Piscirickettsia salmonis LF-89-like (PS-LF-89) and EM-90-like (PS-EM-90) using a cohabitation challenge. The pathogenesis of cohabitant fish infected with the two isolates was relatively different due to cohabitant fish infected with PS-EM-90 showing higher cumulative mortality and shorter time until death compared with PS-LF-89 fish. PS-LF-89 caused an SRS infection characterized by kidney and liver lesions, whereas PS-EM-90 caused systemic and haemorrhagic disease characterized by kidney, liver, heart, brain, skeletal muscle and intestine lesions. Decreased serum concentration of total proteins and albumin as well as increased serum ALT, AST and creatinine levels in fish infected with both isolates confirmed that changes in liver and kidney function occurred during infection. Tissue damage, expressed as an SRS histoscore, showed a strong positive correlation with the bacterial load expressed as abundance of P. salmonis 16S rRNA transcripts in the livers and kidneys of fish affected with either isolate, but the correlation was significantly higher in fish infected with PS-EM-90. The results contribute to improving the understanding of the bacteria-host interaction. © 2017 John Wiley & Sons Ltd.

  13. Time-related changes of the intestinal morphology of Atlantic salmon, Salmo salar L., at two different soybean meal inclusion levels

    NARCIS (Netherlands)

    Urán, P.; Schrama, J.W.; Rombout, J.H.W.M.; Taverne-Thiele, J.J.; Obach, A.; Koppe, W.; Verreth, J.A.J.

    2009-01-01

    Abstract Soybean meal (SBM) induces enteritis in the distal intestine of Atlantic salmon. The present study assesses the effects of SBM concentrations on the kinetics of the enteritis process. Fish of 300 g, kept at 12 degrees C, were fed diets with different SBM inclusions: 0%, 10% and 20% SBM for

  14. 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).

  15. Short-Term Market Risks Implied by Weekly Options

    DEFF Research Database (Denmark)

    Andersen, Torben Gustav; Fusari, Nicola; Todorov, Viktor

    We study short-term market risks implied by weekly S&P 500 index options. The introduction of weekly options has dramatically shifted the maturity profile of traded options over the last five years, with a substantial proportion now having expiry within one week. Such short-dated options provide...... a direct way to study volatility and jump risks. Unlike longer-dated options, they are largely insensitive to the risk of intertemporal shifts in the economic environment. Adopting a novel semi-nonparametric approach, we uncover variation in the negative jump tail risk which is not spanned by market......" by the level of market volatility and elude standard asset pricing models....

  16. Implied Reading in the Unforgettable Stories of Language Learners

    Directory of Open Access Journals (Sweden)

    Feryal ÇUBUKÇU

    2017-09-01

    Full Text Available Iser is literary theoretician and co-founder of the Constance School of Reception Aesthetics, professor Emeritus of English and Comparative Literature at the University of Constance and the University of California, Irvine. When Iser died in 2007 in his eighty-first year, he was one of the most widely known literary theoreticians in the world. His “implied reading” theory claims that texts can themselves also awaken false expectations, alternately bringing about surprise, joy and frustration, which can be the enlargement of experience. The indeterminacy of the text might yield different responses from different readers. To prove that each implied reading is based on the schemata of the readers, this study aims at analysing the stories told by language learners of Turkish who come from 20 countries and whose ages vary between 18-32. The participants are 65 undergraduate and graduate university students, from African, Asian and Balkan countries, who upon watching “Cinderella” were asked to write about the unforgettable folk story or fairy tale. When their stories are item analysed, the results show that the schematas of the learners shape the way they choose and recount the stories. Leraners of Turkish fill in the gaps throughout the story, form a meaningful bond by pulling information from it, participating in a reciprocal relationship, creating and deriving meaning in an extravaganza of interpretation.

  17. Implied motion language can influence visual spatial memory.

    Science.gov (United States)

    Vinson, David W; Engelen, Jan; Zwaan, Rolf A; Matlock, Teenie; Dale, Rick

    2017-07-01

    How do language and vision interact? Specifically, what impact can language have on visual processing, especially related to spatial memory? What are typically considered errors in visual processing, such as remembering the location of an object to be farther along its motion trajectory than it actually is, can be explained as perceptual achievements that are driven by our ability to anticipate future events. In two experiments, we tested whether the prior presentation of motion language influences visual spatial memory in ways that afford greater perceptual prediction. Experiment 1 showed that motion language influenced judgments for the spatial memory of an object beyond the known effects of implied motion present in the image itself. Experiment 2 replicated this finding. Our findings support a theory of perception as prediction.

  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. Collective memory in primate conflict implied by temporal scaling collapse.

    Science.gov (United States)

    Lee, Edward D; Daniels, Bryan C; Krakauer, David C; Flack, Jessica C

    2017-09-01

    In biological systems, prolonged conflict is costly, whereas contained conflict permits strategic innovation and refinement. Causes of variation in conflict size and duration are not well understood. We use a well-studied primate society model system to study how conflicts grow. We find conflict duration is a 'first to fight' growth process that scales superlinearly, with the number of possible pairwise interactions. This is in contrast with a 'first to fail' process that characterizes peaceful durations. Rescaling conflict distributions reveals a universal curve, showing that the typical time scale of correlated interactions exceeds nearly all individual fights. This temporal correlation implies collective memory across pairwise interactions beyond those assumed in standard models of contagion growth or iterated evolutionary games. By accounting for memory, we make quantitative predictions for interventions that mitigate or enhance the spread of conflict. Managing conflict involves balancing the efficient use of limited resources with an intervention strategy that allows for conflict while keeping it contained and controlled. © 2017 The Author(s).

  20. Stringent Mitigation Policy Implied By Temperature Impacts on Economic Growth

    Science.gov (United States)

    Moore, F.; Turner, D.

    2014-12-01

    Integrated assessment models (IAMs) compare the costs of greenhouse gas mitigation with damages from climate change in order to evaluate the social welfare implications of climate policy proposals and inform optimal emissions reduction trajectories. However, these models have been criticized for lacking a strong empirical basis for their damage functions, which do little to alter assumptions of sustained GDP growth, even under extreme temperature scenarios. We implement empirical estimates of temperature effects on GDP growth-rates in the Dynamic Integrated Climate and Economy (DICE) model via two pathways, total factor productivity (TFP) growth and capital depreciation. Even under optimistic adaptation assumptions, this damage specification implies that optimal climate policy involves the elimination of emissions in the near future, the stabilization of global temperature change below 2°C, and a social cost of carbon (SCC) an order of magnitude larger than previous estimates. A sensitivity analysis shows that the magnitude of growth effects, the rate of adaptation, and the dynamic interaction between damages from warming and GDP are three critical uncertainties and an important focus for future research.

  1. IMPLIED-IN-PRICES EXPECTATIONS: THEIR ROLE IN ARBITRAGE

    Directory of Open Access Journals (Sweden)

    Sergei A. Ivanov

    2014-02-01

    Full Text Available Real prices are created on markets by supply and demand and they do not have to follow some distributions or have some properties, which we often assume. However, prices have to follow some rules in order to make arbitrage impossible. Existence of arbitrage opportunities means existence of inefficiency. Prices always contain expectations about future. Constraints on such expectations and arbitrage mechanisms were investigated with minimum assumptions about price processes (e.g. real prices do not have to be martingales. It was shown that found constraints could be easily failed in some widespread conditions. Fluctuating risk-free interest rates creates excess amount of asset in comparison with case when they are constant. This property allows arbitrage and making risk-free profit. This possibility is hard to use. However, in theory it exists almost on every market. Interest rate is implied in almost every price. The possibility exists where there is uncertainty about future. This leads to assumption that there is very fundamental inefficiency, which potentially is able to change markets dramatically.

  2. MÉTODO EXEGÉTICO PARA INTERPRETAR OS SALMOS

    Directory of Open Access Journals (Sweden)

    Luís Stadelmann

    1998-01-01

    Full Text Available A chave hermenêutica para uma adequada interpretação dos salmos está na aplicação do método de investigação para entender a linguagem, o conteúdo e a significação do texto escrito. O método histórico-crítico analisa o texto como a expressão do salmista em circunstâncias concretas de sua época e de sentido diretamente intencionado; depois, estudando a fisionomia literária do texto, assinala, em cada unidade, as partes que contêm elementos constitutivos de determinado gênero literário e a temática nelas explanada. Dada a diversidade dos assuntos, sua análise leva em consideração o conteúdo da teologia bíblica do AT bem como os temas da liturgia e da espiritualidade.

  3. 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.

  4. Analysis of Federal Subsidies: Implied Price of Carbon

    Energy Technology Data Exchange (ETDEWEB)

    D. Craig Cooper; Thomas Foulke

    2010-10-01

    For informed climate change policy, it is important for decision makers to be able to assess how the costs and benefits of federal energy subsidies are distributed and to be able to have some measure to compare them. One way to do this is to evaluate the implied price of carbon (IPC) for a federal subsidy, or set of subsidies; where the IPC is the cost of the subsidy to the U.S. Treasury divided by the emissions reductions it generated. Subsidies with lower IPC are more cost effective at reducing greenhouse gas emissions, while subsidies with a negative IPC act to increase emissions. While simple in concept, the IPC is difficult to calculate in practice. Calculation of the IPC requires knowledge of (i) the amount of energy associated with the subsidy, (ii) the amount and type of energy that would have been produced in the absence of the subsidy, and (iii) the greenhouse gas emissions associated with both the subsidized energy and the potential replacement energy. These pieces of information are not consistently available for federal subsidies, and there is considerable uncertainty in cases where the information is available. Thus, exact values for the IPC based upon fully consistent standards cannot be calculated with available data. However, it is possible to estimate a range of potential values sufficient for initial comparisons. This study has employed a range of methods to generate “first order” estimates for the IPC of a range of federal subsidies using static methods that do not account for the dynamics of supply and demand. The study demonstrates that, while the IPC value depends upon how the inquiry is framed and the IPC cannot be calculated in a “one size fits all” manner, IPC calculations can provide a valuable perspective for climate policy analysis. IPC values are most useful when calculated within the perspective of a case study, with the method and parameters of the calculation determined by the case. The IPC of different policy measures can

  5. 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

  6. 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

  7. 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 ...

  8. 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...

  9. Implied and Realized Volatility in the Cross-Section of Equity Options

    DEFF Research Database (Denmark)

    Ammann, Manuel; Skovmand, David; Verhofen, Michael

    2009-01-01

    Using a complete sample of US equity options, we analyze patterns of implied volatility in the cross-section of equity options with respect to stock characteristics. We find that high-beta stocks, small stocks, stocks with a low-market-to-book ratio, and non-momentum stocks trade at higher implied...... volatilities after controlling for historical volatility. We find evidence that implied volatility overestimates realized volatility for low-beta stocks, small caps, low-market-to-book stocks, and stocks with no momentum and vice versa. However, we cannot reject the null hypothesis that implied volatility...

  10. 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

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

    Science.gov (United States)

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

    2017-01-01

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

  12. Scale invariance implies conformal invariance for the three-dimensional Ising model.

    Science.gov (United States)

    Delamotte, Bertrand; Tissier, Matthieu; Wschebor, Nicolás

    2016-01-01

    Using the Wilson renormalization group, we show that if no integrated vector operator of scaling dimension -1 exists, then scale invariance implies conformal invariance. By using the Lebowitz inequalities, we prove that this necessary condition is fulfilled in all dimensions for the Ising universality class. This shows, in particular, that scale invariance implies conformal invariance for the three-dimensional Ising model.

  13. Does “quorum sensing” imply a new type of biological information?

    DEFF Research Database (Denmark)

    Bruni, Luis Emilio

    2002-01-01

    of biological information implied by genetic information with that implied in the concept of “quorum sensing” (which refers to a prokaryotic cell-to-cell communication system) in order to explore if such integration is being achieved. I use the Lux operon paradigm and the Vibrio fischeri – Euprymna scolopes...

  14. Fractional Black–Scholes option pricing, volatility calibration and implied Hurst exponents in South African context

    Directory of Open Access Journals (Sweden)

    Emlyn Flint

    2017-03-01

    Full Text Available Background: Contingent claims on underlying assets are typically priced under a framework that assumes, inter alia, that the log returns of the underlying asset are normally distributed. However, many researchers have shown that this assumption is violated in practice. Such violations include the statistical properties of heavy tails, volatility clustering, leptokurtosis and long memory. This paper considers the pricing of contingent claims when the underlying is assumed to display long memory, an issue that has heretofore not received much attention. Aim: We address several theoretical and practical issues in option pricing and implied volatility calibration in a fractional Black–Scholes market. We introduce a novel eight-parameter fractional Black–Scholes-inspired (FBSI model for the implied volatility surface, and consider in depth the issue of calibration. One of the main benefits of such a model is that it allows one to decompose implied volatility into an independent long-memory component – captured by an implied Hurst exponent – and a conditional implied volatility component. Such a decomposition has useful applications in the areas of derivatives trading, risk management, delta hedging and dynamic asset allocation. Setting: The proposed FBSI volatility model is calibrated to South African equity index options data as well as South African Rand/American Dollar currency options data. However, given the focus on the theoretical development of the model, the results in this paper are applicable across all financial markets. Methods: The FBSI model essentially combines a deterministic function form of the 1-year implied volatility skew with a separate deterministic function for the implied Hurst exponent, thus allowing one to model both observed implied volatility surfaces as well as decompose them into independent volatility and long-memory components respectively. Calibration of the model makes use of a quasi-explicit weighted

  15. PROFIL PROTEIN DAN ASAM AMINO KEONG IPONG-IPONG (Fasciolaria salmo PADA PENGOLAHAN YANG BERBEDA

    Directory of Open Access Journals (Sweden)

    Sri Purwaningsih

    2013-11-01

    Full Text Available ABSTRACTIpong-Ipong (Fasciolaria salmo snail is a mollusk from marine gastropod class in Cirebon, West Java which is consumed by public and believed to improve health, but no research on the protein and amino acid content. This study aimed to determine the proximate content, acid insoluble ash, amino acids (before and after treatment, and content of taurine on the best methods. The research was conducted in two parts. The first part covers sampling, identification, preparation, determination of size and weight, calculation of body recovery, processing, and organoleptic tests. The second part consists of processing treatments boiling (100ºC for 15 minutes, steaming (100ºC for 20 minutes, and boiling with the addition of 3% salt for 15 minutes. The results showed that the treatment gives a significant effect in fat, protein, water, ash and acid insoluble ash content (α=0.05. The highest content of essential amino acids in Ipong-ipong snail was arginine and non-essential amino acid was glutamic. The treatment method causes decreased in amino acid content. Steaming resulted in a decrease of taurine content of 164.17 mg/100 g to 149.62 mg/100 g.Keywords: amino acids, Fasciolaria salmo, protein, taurineABSTRAKKeong Ipong-ipong (Fasciolaria salmo merupakan moluska dari kelas gastropoda laut di Cirebon, Jawa Barat yang dikonsumsi oleh masyarakat dan diyakini dapat meningkatkan kesehatan, namun belum pernah ada penelitian mengenai kandungan protein dan asam aminonya. Penelitian ini bertujuan untuk menentukan kandungan proksimat, abu tak larut asam, asam amino (sebelum dan setelah pengolahan, serta kandungan taurin pada metode terbaik. Penelitian ini dilakukan dalam dua bagian. Bagian pertama meliputi pengambilan sampel, identifikasi, preparasi, penentuan ukuran dan bobot, perhitungan rendemen tubuh, pengolahan, dan uji organoleptik. Bagian kedua meliputi perlakuan pengolahan terdiri dari perebusan (100ºC selama 15 menit, pengukusan (100ºC selama 20

  16. Survival of sea-water-adapted trout, Salmo trutta L. ranched in a Danish fjord

    DEFF Research Database (Denmark)

    Pedersen, Stig; Rasmussen, Gorm

    2000-01-01

    The effect of seawater adaptation on the survival of coastally released post-smelt trout, Salmo trutta L., was investigated by release: (1) directly (with no adaptation); (2) after retention in net pens in the sea for 29-131 days (delayed release); (3) after feeding with a high salt diet (12...... survival rate. A longer adaptation period did not increase survival. On average, survival was increased by 36%. Survival was not increased by high-salt diets. Until attainment of the legal size for capture, survival was 9.6% higher on average, with extremes as low as 1.7% and as high as 38% in individual...

  17. Museum samples could help to reconstruct the original distribution of Salmo trutta complex in Italy.

    Science.gov (United States)

    Splendiani, A; Fioravanti, T; Giovannotti, M; Olivieri, L; Ruggeri, P; Nisi Cerioni, P; Vanni, S; Enrichetti, F; Caputo Barucchi, V

    2017-06-01

    Partial D-loop sequences of museum specimens of brown trout and marble trout (Salmo trutta species complex) collected from Mediterranean rivers in the late 19th century were analysed to help to describe the native distribution of these species. All the individuals studied carried native haplotypes, the geographic distribution of which is consistent with published data. These results indicate that museum specimens from the 19th century could represent an opportunity to get a picture of the original genetic diversity distribution of this species complex. © 2017 The Fisheries Society of the British Isles.

  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. Marine depth use of sea trout Salmo trutta in fjord areas of central Norway

    DEFF Research Database (Denmark)

    Eldøy, S. H.; Davidsen, J. G.; Thorstad, E. B.

    2017-01-01

    S. trutta utilize marine water bodies commonly influenced by anthropogenic factors such as aquaculture, harbours and marine constructions, marine renewable energy production or other human activity. This suggests that the marine behaviour of S. trutta and its susceptibility to coastal anthropogenic......The vertical behaviour of 44 veteran sea trout Salmo trutta (275-580 mm) in different marine fjord habitats (estuary, pelagic, near shore with and without steep cliffs) was documented during May-February by acoustic telemetry. The swimming depth of S. trutta was influenced by habitat, time of day...... factors should be considered in marine planning processes....

  20. Diel foraging and shelter use of large juvenile brown trout (Salmo trutta) under food satiation

    DEFF Research Database (Denmark)

    Conallin, J.; Jyde, M.; Filrup, K.

    2012-01-01

    The diel partitioning of juvenile brown trout Salmo trutta foraging behaviour is controlled by a number of factors including predation risk, competition, temperature and food availability. The present study uses PIT-tagging and visual observation to asses the use of shelter and foraging behaviour...... of Danish wild juvenile brown trout (13.5-15.6 cm). The experiment was conducted in a fluvarium and the fish were fed to satiation. It was hypothesised that food satiation would promote nocturnal foraging and increase daytime shelter use. Our results showed a significant difference in diel shelter use...

  1. 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

    in a fjord system during April–September in 2012–2013. Overall, fish spent 68% of their marine residence time close to river mouths (... residence time was 7–183 days and was positively correlated to body length and smolt age, but negatively correlated to the date of sea entry......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...

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

    Science.gov (United States)

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

    2016-04-01

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

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

    Directory of Open Access Journals (Sweden)

    Gimeno, M. J.

    1996-04-01

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

  4. Separating neural activity associated with emotion and implied motion: An fMRI study.

    Science.gov (United States)

    Kolesar, Tiffany A; Kornelsen, Jennifer; Smith, Stephen D

    2017-02-01

    Previous research provides evidence for an emo-motoric neural network allowing emotion to modulate activity in regions of the nervous system related to movement. However, recent research suggests that these results may be due to the movement depicted in the stimuli. The purpose of the current study was to differentiate the unique neural activity of emotion and implied motion using functional MRI. Thirteen healthy participants viewed 4 sets of images: (a) negative stimuli implying movement, (b) negative stimuli not implying movement, (c) neutral stimuli implying movement, and (d) neutral stimuli not implying movement. A main effect for implied motion was found, primarily in regions associated with multimodal integration (bilateral insula and cingulate), and visual areas that process motion (bilateral middle temporal gyrus). A main effect for emotion was found primarily in occipital and parietal regions, indicating that emotion enhances visual perception. Surprisingly, emotion also activated the left precentral gyrus, a motor region. These results demonstrate that emotion elicits activity above and beyond that evoked by the perception of implied movement, but that the neural representations of these characteristics overlap. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  5. Dicty_cDB: SHF448 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available |CV428924.1 EST02153 Atlantic salmon Lambda Zap Express heart cDNA library Salmo salar cDNA clone hr_004_h06 5'...CK882927 |CK882927.1 SGP147615 Atlantic salmon Heart cDNA library Salmo salar cDNA clone H6-0590, mRNA

  6. Impact of groundwater abstraction on physical habitat of brown trout (Salmo trutta) in a small Danish stream

    DEFF Research Database (Denmark)

    Olsen, M.; Bøgh, E.; Pedersen, Stig

    2009-01-01

    The purpose of this study was to assess the impact of groundwater abstraction on stream discharge and physical habitat conditions for brown trout (Salmo trutta) in a small Danish stream. Stream discharge was simulated using a lumped hydrological model (NAM) and a scenario was set up for stream di...

  7. Market-implied risk-neutral probabilities, actual probabilities, credit risk and news

    Directory of Open Access Journals (Sweden)

    Shashidhar Murthy

    2011-09-01

    Full Text Available Motivated by the credit crisis, this paper investigates links between risk-neutral probabilities of default implied by markets (e.g. from yield spreads and their actual counterparts (e.g. from ratings. It discusses differences between the two and clarifies underlying economic intuition using simple representations of credit risk pricing. Observed large differences across bonds in the ratio of the two probabilities are shown to imply that apparently safer securities can be more sensitive to news.

  8. Motor mapping of implied actions during perception of emotional body language.

    Science.gov (United States)

    Borgomaneri, Sara; Gazzola, Valeria; Avenanti, Alessio

    2012-04-01

    Perceiving and understanding emotional cues is critical for survival. Using the International Affective Picture System (IAPS) previous TMS studies have found that watching humans in emotional pictures increases motor excitability relative to seeing landscapes or household objects, suggesting that emotional cues may prime the body for action. Here we tested whether motor facilitation to emotional pictures may reflect the simulation of the human motor behavior implied in the pictures occurring independently of its emotional valence. Motor-evoked potentials (MEPs) to single-pulse TMS of the left motor cortex were recorded from hand muscles during observation and categorization of emotional and neutral pictures. In experiment 1 participants watched neutral, positive and negative IAPS stimuli, while in experiment 2, they watched pictures depicting human emotional (joyful, fearful), neutral body movements and neutral static postures. Experiment 1 confirms the increase in excitability for emotional IAPS stimuli found in previous research and shows, however, that more implied motion is perceived in emotional relative to neutral scenes. Experiment 2 shows that motor excitability and implied motion scores for emotional and neutral body actions were comparable and greater than for static body postures. In keeping with embodied simulation theories, motor response to emotional pictures may reflect the simulation of the action implied in the emotional scenes. Action simulation may occur independently of whether the observed implied action carries emotional or neutral meanings. Our study suggests the need of controlling implied motion when exploring motor response to emotional pictures of humans. Copyright © 2012 Elsevier Inc. All rights reserved.

  9. O SALMO 22 (21 E A HISTÓRIA DA PAIXÃO

    Directory of Open Access Journals (Sweden)

    Luís I. J. Stadelmann

    1983-01-01

    Full Text Available As freqüentes citações do SI 22 (21 na "História da Paixão" provam que a Igreja primitiva viu íntima relação entre as palavras angustiadas de Jesus na cruz e a suprema aflição do justo sofredor. Aqui têm sua expressão mais candente a angústia humana, a tentação ao desespero e o milagre da reversão do sofrimento em júbilo de salvação. Ao assumir a provação extrema de se sentir abandonado por Deus, Cristo penetrou no mais profundo isolamento humano e assumiu nosso sofrimento até o extremo. A indagação desesperada dos que mais sofreram neste mundo é conhecida por aquele no qual a bondade divina se encarnou. Sendo a morte de Cristo o paradigma do sofrimento humano, este salmo, integrado na "História da Paixão", é representativo dos-salmos de lamentação.

  10. Kinematics and energetics of swimming performance during acute warming in brown trout Salmo trutta.

    Science.gov (United States)

    Lea, J M D; Keen, A N; Nudds, R L; Shiels, H A

    2016-01-01

    This study examined how acute warming of water temperature affects the mechanical efficiency of swimming and aerobic capabilities of the brown trout Salmo trutta. Swimming efficiency was assessed using the relationship between swimming kinematics and forward speed (U), which is thought to converge upon an optimum range of a dimensionless parameter, the Strouhal number (St ). Swim-tunnel intermittent stopped-flow respirometry was used to record kinematics and measure oxygen consumption (ṀO2) of S. trutta during warming and swimming challenges. Salmo trutta maintained St between 0·2 and 0·3 at any given U over a range of temperatures, irrespective of body size. The maintenance of St within the range for maximum efficiency for oscillatory propulsion was achieved through an increase in tail-beat frequency (ftail) and a decrease in tail-beat amplitude (A) as temperature increased. Maintenance of efficient steady-state swimming was fuelled by aerobic metabolism, which increased as temperature increased up to 18° C but declined above this temperature, decreasing the apparent metabolic scope. As St was maintained over the full range of temperatures whilst metabolic scope was not, the results may suggest energetic trade-offs at any given U at temperatures above thermal optima. © 2015 The Fisheries Society of the British Isles.

  11. Implied adjusted volatility functions: Empirical evidence from Australian index option market

    Science.gov (United States)

    Harun, Hanani Farhah; Hafizah, Mimi

    2015-02-01

    This study aims to investigate the implied adjusted volatility functions using the different Leland option pricing models and to assess whether the use of the specified implied adjusted volatility function can lead to an improvement in option valuation accuracy. The implied adjusted volatility is investigated in the context of Standard and Poor/Australian Stock Exchange (S&P/ASX) 200 index options over the course of 2001-2010, which covers the global financial crisis in the mid-2007 until the end of 2008. Both in- and out-of-sample resulted in approximately similar pricing error along the different Leland models. Results indicate that symmetric and asymmetric models of both moneyness ratio and logarithmic transformation of moneyness provide the overall best result in both during and post-crisis periods. We find that in the different period of interval (pre-, during and post-crisis) is subject to a different implied adjusted volatility function which best explains the index options. Hence, it is tremendously important to identify the intervals beforehand in investigating the implied adjusted volatility function.

  12. Level Shifts in Volatility and the Implied-Realized Volatility Relation

    DEFF Research Database (Denmark)

    Christensen, Bent Jesper; de Magistris, Paolo Santucci

    We propose a simple model in which realized stock market return volatility and implied volatility backed out of option prices are subject to common level shifts corresponding to movements between bull and bear markets. The model is estimated using the Kalman filter in a generalization to the mult......We propose a simple model in which realized stock market return volatility and implied volatility backed out of option prices are subject to common level shifts corresponding to movements between bull and bear markets. The model is estimated using the Kalman filter in a generalization...... to the multivariate case of the univariate level shift technique by Lu and Perron (2008). An application to the S&P500 index and a simulation experiment show that the recently documented empirical properties of strong persistence in volatility and forecastability of future realized volatility from current implied...

  13. P3-27: Eye-Movement of Observers Viewing Implied Motion in Abstract Paintings

    Directory of Open Access Journals (Sweden)

    Ji-Eun Kim

    2012-10-01

    Full Text Available Artists such as Duchamp and Balla tried to portray moving objects on static canvases by superimposing snapshots of moving objects. Previously, our group showed the influence of prior experience on brain responses within a motion-sensitive area MT+ to abstract paintings with or without implied motion (Kim and Blake, 2007 Spatial Vision 20 545–560. In the present study, we went further to investigate whether the differential MT+ activation between observers is originated from differential eye movement patterns. This hypothesis is not far-fetched since previous studies have shown that the way artistic experts view abstract paintings is different from that of naïve observers (Vogt and Magnussen, 2007 Perception 36 91–100. Methods: 2 groups of observers (expert in art vs. naïve were tested. 2 abstract paintings with implied motion (‘Nude descending a staircase No. 2’ and ‘Girl running on a balcony’, 2 abstract paintings without implied motion (‘Park bei Lu’ and ‘Composition No. II’, and 2 chronophotographs were presented for 5 s. After each stimulus presentation while their eye movement was recorded, observers performed 1 back task. Results: Experts, when viewing paintings with implied motion, tended to focus more on the parts of paintings portraying motion – e.g., head and feet of moving creatures– than did naïve observers. In addition, experts, unlike naïve observers, moved their eyes in the direction corresponding to the direction of moving objects in those paintings. Results imply that experts and naïve observers are different in terms of “where” and “how” they view abstract paintings with implied motion.

  14. Latent Integrated Stochastic Volatility, Realized Volatility, and Implied Volatility: A State Space Approach

    DEFF Research Database (Denmark)

    Bach, Christian; Christensen, Bent Jesper

    We include simultaneously both realized volatility measures based on high-frequency asset returns and implied volatilities backed out of individual traded at the money option prices in a state space approach to the analysis of true underlying volatility. We model integrated volatility as a latent...... process is downward biased. Implied volatility performs better than any of the alternative realized measures when forecasting future integrated volatility. The results are largely similar across the stock market (S&P 500), bond market (30-year U.S. T-bond), and foreign currency exchange market ($/£ )....

  15. Towards a New Model for Implied Metaphor Translation: English Translations of "Al Muallaqat"

    Science.gov (United States)

    Al-Garrallah, Aiman Sanad

    2016-01-01

    This two-part paper argues that metaphor in both English and Arabic is defined and classified in almost the same way with some slight, but far from insignificant, differences. Those differences along with the linguistic nature of implied metaphor can be attributed to the failure in translating that type of metaphor from Arabic into English as…

  16. 77 FR 2056 - Merrimac Paper Company, Inc.; Notice of Termination of License by Implied Surrender and...

    Science.gov (United States)

    2012-01-13

    ... Energy Regulatory Commission Merrimac Paper Company, Inc.; Notice of Termination of License by Implied... Surrender. b. Project No.: 2928-007. c. Date Initiated: January 06, 2012. d. Licensee: Merrimac Paper... documents may be filed electronically via the Internet in lieu of paper. See 18 CFR 385.2001(a)(1)(iii) and...

  17. Images of Childhood and the Implied Reader in Young Children's Information Books

    Science.gov (United States)

    Larkin-Lieffers, Patricia A.

    2010-01-01

    Images of childhood are ideas and expectations of childhood and children, and are reflections of individual perception and cultural ideologies. In writing children's books, authors draw on their conscious and unconscious thoughts of childhood to create an implied reader. In this paper I investigate images of childhood through examination of the…

  18. How the 52-week high and low affect option-implied volatilities and stock return moments

    NARCIS (Netherlands)

    Driessen, J.J.A.G.; Lin, T.C.; van Hemert, O.

    2013-01-01

    We provide a new perspective on option and stock price behavior around 52-week highs and lows. We analyze whether option-implied volatilities (IVs) change when stock prices approach or break through their 52-week high or low. We also study the effects of highs and lows on a stock’s beta and return

  19. Size Does Matter: Implied Object Size is Mentally Simulated during Language Comprehension

    Science.gov (United States)

    de Koning, Björn B.; Wassenburg, Stephanie I.; Bos, Lisanne T.; Van der Schoot, Menno

    2017-01-01

    Embodied theories of language comprehension propose that readers construct a mental simulation of described objects that contains perceptual characteristics of their real-world referents. The present study is the first to investigate directly whether implied object size is mentally simulated during sentence comprehension and to study the potential…

  20. Adaptation to real motion reveals direction-selective interactions between real and implied motion processing

    NARCIS (Netherlands)

    Lorteije, J.A.M.; Kenemans, J.L.; Jellema, T.; van der Lubbe, R.H.J.; Lommers, M.W.; Wezel, R.J.A. van

    2007-01-01

    Viewing static pictures of running humans evokes neural activity in the dorsal motion-sensitive cortex. To establish whether this response arises from direction-selective neurons that are also involved in real motion processing, we measured the visually evoked potential to implied motion following

  1. Delayed Response to Animate Implied Motion in Human Motion Processing Areas

    NARCIS (Netherlands)

    Lorteije, Jeannette A.M.; Kenemans, J. Leon; Jellema, Tjeerd; van der Lubbe, Robert Henricus Johannes; de Heer, Frederiek; van Wezel, Richard Jack Anton

    2006-01-01

    Viewing static photographs of objects in motion evokes higher fMRI activation in the human medial temporal complex (MT+) than looking at similar photographs without this implied motion. As MT+ is traditionally thought to be involved in motion perception (and not in form perception), this finding

  2. Adaption to Real Motion Reveals Direction-selective Interactions between Real and Implied Motion Processing.

    NARCIS (Netherlands)

    Lorteije, Jeannette A.M.; Kenemans, Leon; Jellema, Tjeerd; van der Lubbe, Robert Henricus Johannes; Lommers, Marjolein W.; van Wezel, Richard Jack Anton

    2007-01-01

    Viewing static pictures of running humans evokes neural activity in the dorsal motion-sensitive cortex. To establish whether this response arises from direction-selective neurons that are also involved in real motion processing, we measured the visually evoked potential to implied motion following

  3. Aplikasi Algoritma Biseksi dan Newton-Raphson dalam Menaksir Nilai Volatilitas Implied

    Directory of Open Access Journals (Sweden)

    Komang Dharmawan

    2012-11-01

    Full Text Available Volatilitas adalah suatu besaran yang mengukuran seberapa jauh suatu harga sahambergerak dalam suatu periode tertentu dapat juga diartikan sebagai persentase simpanganbaku dari perubahan harga harian suatu saham. Menurut teori yang dikembangkan oleh Black-Scholes in 1973, semua harga opsi dengan ’underlying asset’ dan waktu jatuh tempo yang samatetapi memiliki nilai exercise yang berbeda akan memiliki nilai volatilitas implied yang sama.Model Black-Scholes dapat dipakai mengestimasi nilai volatilitas implied dari suatu sahamdengan mencari sulusi numerik dari persamaan invers dari model Black-Scholes. Makalah inimendemonstrasikan bagaimana menghitung nilai volatilitas implied suatu saham dengan mengasumsikanbahwa model Black-schole adalah benar dan suatu kontrak opsi dengan denganumur kontrak yang sama akan memiliki harga yang sama. Menggunakan data harga opsi SonyCorporation (SNE, Cisco Systems, Inc (CSCO, dan Canon, Inc (CNJ diperoleh bahwa, ImpliedVolatility memberikan harga yang lebih murah dibandingkan dengan harga opsi darivolatilitas yang dihitung dari data historis. Selain itu, dari hasil iterasi yang diperoleh, metodeNewton-Raphson lebih cepat konvergen dibandingkan dengan metode Bisection.

  4. Polynomial algorithms that prove an NP-hard hypothesis implies an NP-hard conclusion

    NARCIS (Netherlands)

    Bauer, D.; Broersma, Haitze J.; Morgana, A.; Schmeichel, E.

    1999-01-01

    A number of results in Hamiltonian graph theory are of the form $\\mathcal{P}$$_{1}$ implies $\\mathcal{P}$$_{2}$, where $\\mathcal{P}$$_{1}$ is a property of graphs that is NP-hard and $\\mathcal{P}$$_{2}$ is a cycle structure property of graphs that is also NP-hard. Such a theorem is the well-known

  5. Implied Volatility of Interest Rate Options: An Empirical Investigation of the Market Model

    DEFF Research Database (Denmark)

    Christiansen, Charlotte; Hansen, Charlotte Strunk

    2002-01-01

    We analyze the empirical properties of the volatility implied in options on the 13-week US Treasury bill rate. These options have not been studied previously. It is shown that a European style put option on the interest rate is equivalent to a call option on a zero-coupon bond. We apply the LIBOR...

  6. Delayed response to animate implied motion in human motion processing areas

    NARCIS (Netherlands)

    Lorteije, J.A.M.; Kenemans, J.L.; Jellema, T.; Lubbe, R.H.J. van der; Heer, F. de; Wezel, R.J.A. van

    2006-01-01

    Viewing static photographs of objects in motion evokes higher fMRI activation in the human medial temporal complex (MT+) than looking at similar photographs without this implied motion. As MT+ is traditionally thought to be involved in motion perception (and not in form perception), this finding

  7. 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......, analyses of the stocked populations revealed that the genetic integrity of the local populations had been substantially changed, and the populations must be characterized as hybrid swarms. The pattern of population differentiation observed at microsatellites contrasted to that depicted previously by mt...

  8. 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 the stream and then released at the capture site. Using telemetry, we subsequently classified fish as resident, short-distance migrants (potamodromous), or long-distance migrants (potentially anadromous). Our results revealed that fish belonging to the resident strategy differed from those exhibiting any...

  9. 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 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....... Low temperature compromised the hypo-osmoregulatory ability, as indicated by insufficient compensatory adjustments of ion-transport mechanisms. Tagging experiments revealed that descent of overwintering fish into the ocean occurred over a narrow time period coincident with increasing water temperature...

  10. 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...... of migration, and whether our manipulations affected growth, condition, and timing of migration. We found that pre-existing differences predicted migration, with smaller individuals and individuals in poor condition having a higher propensity to migrate. Exogenous cortisol manipulation had the largest negative...... effect on growth and condition, and resulted in an earlier migration date. Additionally, low-growth individuals within the temperature and food deprivation treatments migrated earlier. By demonstrating that both pre-existing differences in organism state and additional stressors can affect whether...

  11. 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.

  12. Comparison of vegetable shortening and cocoa butter as vehicles for cortisol manipulation in Salmo trutta

    DEFF Research Database (Denmark)

    Birnie-Gauvin, Kim; Peiman, K. S.; Larsen, M. H.

    2018-01-01

    This study demonstrates that vegetable shortening and cocoa butter are two effective vehicles for intraperitoneal cortisol implants in juvenile teleosts, specifically brown trout Salmo trutta, residing in north temperate freshwater environments. Each vehicle showed a different pattern of cortisol...... elevation. Vegetable shortening was found to be a more suitable vehicle for long-term cortisol elevation [elevated at 3, 6 and 9 days post treatment (dpt)], while cocoa butter may be better suited for short-term cortisol elevation (only elevated at 3 dpt). Additionally, plasma cortisol levels were higher...... with cortisol–vegetable shortening than with cortisol–cocoa butter implants. Plasma glucose levels were elevated 6 and 9 dpt for fishes injected with cortisol–vegetable shortening, but did not change relative to controls and shams in cortisol–cocoa butter fishes. In conclusion, vegetable shortening and cocoa...

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

    Science.gov (United States)

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

    2017-09-01

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

  14. 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.

  15. 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.

  16. Antioxidant nutrition in Atlantic salmon (Salmo salar parr and post-smolt, fed diets with high inclusion of plant ingredients and graded levels of micronutrients and selected amino acids

    Directory of Open Access Journals (Sweden)

    Kristin Hamre

    2016-11-01

    Full Text Available The shift from marine to plant-based ingredients in fish feeds affects the dietary concentrations and bioavailability of micronutrients, amino acids and lipids and consequently warrants a re-evaluation of dietary nutrient recommendations. In the present study, an Atlantic salmon diet high in plant ingredients was supplemented with graded levels of nutrient premix (NP, containing selected amino acids, taurine, cholesterol, vitamins and minerals. This article presents the results on the antioxidant nutrients vitamin C, E and selenium (Se, and effects on tissue redox status. The feed ingredients appeared to contain sufficient levels of vitamin E and Se to cover the requirements to prevent clinical deficiency symptoms. The body levels of α-tocopherol (TOH in parr and that of Se in parr and post-smolt showed a linear relationship with dietary concentration, while α-TOH in post-smolt seemed to be saturable with a breakpoint near 140 mg kg−1. Ascorbic acid (Asc concentration in the basal feed was below the expected minimum requirement, but the experimental period was probably too short for the fish to develop visible deficiency symptoms. Asc was saturable in both parr and post-smolt whole body at dietary concentrations of 190 and 63–89 mg kg−1, respectively. Maximum whole body Asc concentration was approximately 40 mg kg−1 in parr and 14 mg kg−1 in post-smolt. Retention ranged from 41 to 10% in parr and from −206 to 12% in post-smolt with increasing NP supplementation. This indicates that the post-smolts had an extraordinarily high consumption of Asc. Analyses of glutathione (GSH and glutathione disulphide (GSSG concentrations and the calculated GSH based redox potentials in liver and muscle tissue, indicated only minor effects of diets on redox regulation. However, the post-smolt were more oxidized than the parr. This was supported by the high consumption of Asc and high expression of gpx1 and gpx3 in liver. Based on the present trials, the recommendations for supplementation of vitamin C and E in diets for Atlantic salmon are similar to current practices, e.g. 150 mg kg−1 of α-TOH and 190 mg kg−1 Asc which was the saturating concentration in parr. Higher concentrations than what would prevent clinical deficiency symptoms are necessary to protect fish against incidents of oxidative stress and to improve immune and stress responses. There were no indications that the Se requirement exceeded the current recommendation of 0.3 mg kg−1.

  17. Antioxidant nutrition in Atlantic salmon (Salmo salar) parr and post-smolt, fed diets with high inclusion of plant ingredients and graded levels of micronutrients and selected amino acids.

    Science.gov (United States)

    Hamre, Kristin; Sissener, Nini H; Lock, Erik-Jan; Olsvik, Pål A; Espe, Marit; Torstensen, Bente E; Silva, Joana; Johansen, Johan; Waagbø, Rune; Hemre, Gro-Ingunn

    2016-01-01

    The shift from marine to plant-based ingredients in fish feeds affects the dietary concentrations and bioavailability of micronutrients, amino acids and lipids and consequently warrants a re-evaluation of dietary nutrient recommendations. In the present study, an Atlantic salmon diet high in plant ingredients was supplemented with graded levels of nutrient premix (NP), containing selected amino acids, taurine, cholesterol, vitamins and minerals. This article presents the results on the antioxidant nutrients vitamin C, E and selenium (Se), and effects on tissue redox status. The feed ingredients appeared to contain sufficient levels of vitamin E and Se to cover the requirements to prevent clinical deficiency symptoms. The body levels of α-tocopherol (TOH) in parr and that of Se in parr and post-smolt showed a linear relationship with dietary concentration, while α-TOH in post-smolt seemed to be saturable with a breakpoint near 140 mg kg -1 . Ascorbic acid (Asc) concentration in the basal feed was below the expected minimum requirement, but the experimental period was probably too short for the fish to develop visible deficiency symptoms. Asc was saturable in both parr and post-smolt whole body at dietary concentrations of 190 and 63-89 mg kg -1 , respectively. Maximum whole body Asc concentration was approximately 40 mg kg -1 in parr and 14 mg kg -1 in post-smolt. Retention ranged from 41 to 10% in parr and from -206 to 12% in post-smolt with increasing NP supplementation. This indicates that the post-smolts had an extraordinarily high consumption of Asc. Analyses of glutathione (GSH) and glutathione disulphide (GSSG) concentrations and the calculated GSH based redox potentials in liver and muscle tissue, indicated only minor effects of diets on redox regulation. However, the post-smolt were more oxidized than the parr. This was supported by the high consumption of Asc and high expression of gpx1 and gpx3 in liver. Based on the present trials, the recommendations for supplementation of vitamin C and E in diets for Atlantic salmon are similar to current practices, e.g. 150 mg kg -1 of α-TOH and 190 mg kg -1 Asc which was the saturating concentration in parr. Higher concentrations than what would prevent clinical deficiency symptoms are necessary to protect fish against incidents of oxidative stress and to improve immune and stress responses. There were no indications that the Se requirement exceeded the current recommendation of 0.3 mg kg -1 .

  18. Comparative economic performance and carbon footprint of two farming models for producing atlantic salmon (salmo salar): Land-based closed containment system in freshwater and open pen in seawater

    Science.gov (United States)

    Ocean net pen production of Atlantic salmon is approaching 2 million metric tons (MT) annually and has proven to be cost- and energy- efficient. Recently, with technology improvements, freshwater aquaculture of Atlantic salmon from eggs to harvestable size of 4 -5 kg in land-based closed containmen...

  19. 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

    in the salmon fillet. The effect on fish consumers of such a replacement remains to be elucidated. Here, we investigate the effect of excessive dietary LA from soyabean oil (SO) on endocannabinoid levels in Atlantic salmon and mice, and study the metabolic effects in mice when SO replaces FO in feed...

  20. Evaluation of a high-EPA oil from transgenic Camelina sativa in feeds for Atlantic salmon (Salmo salar L.): Effects on tissue fatty acid composition, histology and gene expression.

    Science.gov (United States)

    Betancor, M B; Sprague, M; Sayanova, O; Usher, S; Campbell, P J; Napier, J A; Caballero, M J; Tocher, D R

    2015-07-01

    Currently, one alternative for dietary fish oil (FO) in aquafeeds is vegetable oils (VO) that are devoid of omega-3 (n-3) long-chain polyunsaturated fatty acids (LC-PUFAs). Entirely new sources of n-3 LC-PUFA such as eicosapentaenoic (EPA) and docosahexaenoic (DHA) acids through de novo production are a potential solution to fill the gap between supply and demand of these important nutrients. Camelina sativa was metabolically engineered to produce a seed oil (ECO) with > 20% EPA and its potential to substitute for FO in Atlantic salmon feeds was tested. Fish were fed with one of the three experimental diets containing FO, wild-type camelina oil (WCO) or ECO as the sole lipid sources for 7 weeks. Inclusion of ECO did not affect any of the performance parameters studied and enhanced apparent digestibility of individual n-6 and n-3 PUFA compared to dietary WCO. High levels of EPA were maintained in brain, liver and intestine (pyloric caeca), and levels of DPA and DHA were increased in liver and intestine of fish fed ECO compared to fish fed WCO likely due to increased LC-PUFA biosynthesis based on up-regulation of the genes. Fish fed ECO showed slight lipid accumulation within hepatocytes similar to that with WCO, although not significantly different to fish fed FO. The regulation of a small number of genes could be attributed to the specific effect of ECO (311 features) with metabolism being the most affected category. The EPA oil from transgenic Camelina (ECO) could be used as a substitute for FO, however it is a hybrid oil containing both FO (EPA) and VO (18:2n-6) fatty acid signatures that resulted in similarly mixed metabolic and physiological responses.

  1. Full substitution of fish oil with camelina (Camelina sativa) oil, with partial substitution of fish meal with camelina meal, in diets for farmed Atlantic salmon (Salmo salar) and its effect on tissue lipids and sensory quality.

    Science.gov (United States)

    Hixson, Stefanie M; Parrish, Christopher C; Anderson, Derek M

    2014-08-15

    Camelina oil (CO) and meal (CM) are potential replacements of fish meal (FM) and oil (FO) in aquaculture feeds. CO is high in α-linolenic acid (18:3ω3, ALA) (30%), with an ω3/ω6 ratio >1. This study tested diets with 100% CO, solvent extracted FM (SEFM) and partially substituted FM with 10% CM, in a 16 week feeding trial with Atlantic salmon (initial weight 240 g fish(-1)). Final weight (529-691 g fish(-1)) was not affected by using 100% CO; however it was lower in groups fed SEFM and 10% CM diets. Total lipid in salmon flesh fed a diet with CO, SEFM and CM (22% ww(-1)) was significantly higher than FO flesh (14% ww(-1)). There was no difference in the sensory quality of salmon fillets that were fed either FO or 100% CO diets. This was the first study to use CO as a complete FO replacement in diets for farmed Atlantic salmon. Copyright © 2014 Elsevier Ltd. All rights reserved.

  2. Historical record of trace elements (1983-2007) in scales from Atlantic salmon (Salmo salar): Study of past metal contamination from a copper mine (Ulla River, NW Iberian Peninsula).

    Science.gov (United States)

    Cobelo-García, Antonio; Morán, Paloma; Almécija, Clara; Caballero, Pablo

    2017-12-01

    The chemical composition of fish scales has been reported to reflect the composition of the waters in which fish have been resident, therefore having the potential for the assessment of temporal trends in watershed water quality. Here we studied the historical (1983-2007) metal contamination in the Ulla river (NW Iberian Peninsula) watershed - impacted by a Cu mine that was in operation from 1973 until 1988 - by means of the analysis of major and trace elements in salmon scales. Results indicate the presence of a significant contamination for several metals (especially Cu, Au, Ag, Sb, Zn) during the 1980's. Concentrations of Cu in salmon scales during the influence of the mine (1983-1990) were 20 ± 5 μg/g, exceeding the values for the recent years (1995-2007): 1.8 ± 0.4 μg/g. Concentrations for Au in these two periods were 31 ± 12 and 2.1 ± 1.2 ng/g; for Ag: 21 ± 4 and 4 ± 2 ng/g; for Sb: 48 ± 21 and 15 ± 4 ng/g; and for Zn: 133 ± 16 and 93 ± 10 μg/g. The estimated concentrations of dissolved copper during the operation of the mine indicate a scenario of toxic effects due to sensory impairments in the salmon, and a reduction in scales calcification. The results presented here demonstrate that the analysis of trace elements in archived fish scales is a suitable tool for the reconstruction of the past contamination in aquatic systems, and it can be also used as a non-lethal approach for biomonitoring purposes. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Preliminary Validation of a High Docosahexaenoic Acid (DHA and -Linolenic Acid (ALA Dietary Oil Blend: Tissue Fatty Acid Composition and Liver Proteome Response in Atlantic Salmon (Salmo salar Smolts.

    Directory of Open Access Journals (Sweden)

    Waldo G Nuez-Ortín

    Full Text Available Marine oils are important to human nutrition as the major source of docosahexaenoic acid (DHA, a key omega-3 long-chain (≥C20 polyunsaturated fatty acid (n-3 LC-PUFA that is low or lacking in terrestrial plant or animal oils. The inclusion of fish oil as main source of n-3 LC-PUFA in aquafeeds is mostly limited by the increasing price and decreasing availability. Fish oil replacement with cheaper terrestrial plant and animal oils has considerably reduced the content of n-3 LC-PUFA in flesh of farmed Atlantic salmon. Novel DHA-enriched oils with high alpha-linolenic acid (ALA content will be available from transgenic oilseeds plants in the near future as an alternative for dietary fish oil replacement in aquafeeds. As a preliminary validation, we formulated an oil blend (TOFX with high DHA and ALA content using tuna oil (TO high in DHA and the flaxseed oil (FX high in ALA, and assessed its ability to achieve fish oil-like n-3 LC-PUFA tissue composition in Atlantic salmon smolts. We applied proteomics as an exploratory approach to understand the effects of nutritional changes on the fish liver. Comparisons were made between fish fed a fish oil-based diet (FO and a commercial-like oil blend diet (fish oil + poultry oil, FOPO over 89 days. Growth and feed efficiency ratio were lower on the TOFX diet. Fish muscle concentration of n-3 LC-PUFA was significantly higher for TOFX than for FOPO fish, but not higher than for FO fish, while retention efficiency of n-3 LC-PUFA was promoted by TOFX relative to FO. Proteomics analysis revealed an oxidative stress response indicative of the main adaptive physiological mechanism in TOFX fish. While specific dietary fatty acid concentrations and balances and antioxidant supplementation may need further attention, the use of an oil with a high content of DHA and ALA can enhance tissue deposition of n-3 LC-PUFA in relation to a commercially used oil blend.

  4. Growth hormone transgenesis and polyploidy increase metabolic rate, alter the cardiorespiratory response and influence HSP expression in response to acute hypoxia in Atlantic salmon (Salmo salar) yolk-sac alevins.

    Science.gov (United States)

    Polymeropoulos, Elias T; Plouffe, Debbie; LeBlanc, Sacha; Elliott, Nick G; Currie, Suzie; Frappell, Peter B

    2014-07-01

    Growth hormone (GH)-transgenic Atlantic salmon display accelerated growth rates compared with non-transgenics. GH-transgenic fish also display cardiorespiratory and metabolic modifications that accompany the increased growth rate. An elevated routine metabolic rate has been described for pre- and post-smolt GH-transgenic salmon that also display improvements in oxygen delivery to support the increased aerobic demand. The early ontogenic effects of GH transgenesis on the respiratory and cellular physiology of fish, especially during adverse environmental conditions, and the effect of polyploidy are unclear. Here, we investigated the effects of GH transgenesis and polyploidy on metabolic, heart and ventilation rates and heat shock protein (HSP) levels after exposure to acute hypoxia in post-hatch Atlantic salmon yolk-sac alevins. Metabolic rate decreased with decreasing partial pressures of oxygen in all genotypes. In normoxia, triploid transgenics displayed the highest mass-specific metabolic rates in comparison to diploid transgenics and non-transgenic triploids, which, in contrast, had higher rates than diploid non-transgenics. In hypoxia, we observed a lower mass-specific metabolic rate in diploid non-transgenics compared with all other genotypes. However, no evidence for improved O2 uptake through heart or ventilation rate was found. Heart rate decreased in diploid non-transgenics while ventilation rate decreased in both diploid non-transgenics and triploid transgenics in severe hypoxia. Regardless of genotype or treatment, inducible HSP70 was not expressed in alevins. Following hypoxia, the constitutive isoform of HSP70, HSC70, decreased in transgenics and HSP90 expression decreased in all genotypes. These data suggest that physiological changes through GH transgenesis and polyploidy are manifested during early ontogeny in Atlantic salmon. © 2014. Published by The Company of Biologists Ltd.

  5. Sequence analysis and identification of new isoform of EP4 receptors in different atlantic salmon tissues (Salmo salar L.) and its role in PGE2 induced immunomodulation in vitro.

    Science.gov (United States)

    Guo, Tz Chun; Gamil, Amr Ahmed Abdelrahim; Koenig, Melanie; Evensen, Øystein

    2015-01-01

    PGE2 plays an important role in a broad spectrum of physiological and pathological processes mediated through a membrane-bound G protein-coupled receptor (GPCR) called EP receptor. In mammals, four subtypes of EP receptor (EP 1-4) are identified and each of them functions through different signal transduction pathways. Orthologous EP receptors have also been identified in other non-mammalian species, such as chicken and zebrafish. EP4 is the only identified PGE2 receptor to date in Atlantic salmon but its tissue distribution and function have not been studied in any detail. In this study, we first sequenced EP4 receptor in different tissues and found that the presence of the 3nt deletion in the 5' untranslated region was accompanied by silent mutation at nt 668. While attempting to amplify the same sequence in TO cells (an Atlantic salmon macrophage-like cell line), we failed to obtain the full-length product. Further investigation revealed different isoform of EP4 receptor in TO cells and we subsequently documented its presence in different Atlantic salmon tissues. These two isoforms of EP4 receptor share high homology in their first half of sequence but differ in the second half part with several deletion segments though the final length of coding sequence is the same for two isoforms. We further studied the immunomodulation effect of PGE2 in TO cells and found that PGE2 inhibited the induction of CXCL-10, CCL-4, IL-8 and IL-1β genes expression in a time dependent manner and without cAMP upregulation.

  6. An assessment of the risk of spreading the fish parasite Gyrodactylus salaris to uninfected territories in the European Union with the movement of live Atlantic salmon (Salmo salar) from coastal waters

    DEFF Research Database (Denmark)

    Peeler, E.; Thrush, M.; Paisley, Larry

    2006-01-01

    . This risk assessment was undertaken to establish whether exports of live Atlantic salmon from coastal sites increased the risk of G. salaris introduction and establishment in uninfected EU territories. A scenario tree of events necessary for the introduction and establishment of the parasite was constructed......). Transmission from seawater sites, where salinity is greater than 25 parts per thousand, is only possible if infected fish were introduced hours before export. Furthermore, transport via wellboat in full-strength seawater (33 parts per thousand) reduced the risk of introduction to a negligible level. Similarly......, establishment at the site of destination will also be largely determined by salinity. At high salinities the parasite has only hours to reach freshwater (e.g. via migration on wild fish), and therefore the risk of establishment is extremely low. The risk of G. salaris introduction with the importation...

  7. Effects of feeding a fishmeal-free versus a fishmeal-based diet on post-smolt Atlantic salmon salmo salar performance, water quality, and waste production in recirculation aquaculture systems

    Science.gov (United States)

    The Atlantic salmon farming industry has progressively decreased the proportion of fishmeal used in commercial diets due to rising costs and sustainability concerns. A variety of alternate proteins have been identified to partially replace fishmeal; however, very little research has described the ef...

  8. Addition of a selective breeding program for resistance to sea lice Lepeophtheirus salmonis (Kroyer 1838) to existing lines of Atlantic Salmon, Salmo salar L., at the USDA's National Cold Water Marine Aquaculture Center

    Science.gov (United States)

    Sea lice are likely the single most economically costly pathogen that has faced the salmon farming industry over the past 40 years. The most recent economic estimates put the annual cost of sea lice at just under $500 million USD in 2006. This is likely an underestimate of the current costs to indus...

  9. Influence du maintien en mer des mâles de saumon atlantique