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Sample records for rainbow trout oncorhynchus

  1. Molecular characterization of rainbow trout, Oncorhynchus mykiss

    Indian Academy of Sciences (India)

    Home; Journals; Journal of Genetics; Volume 94; Online resources. Molecular characterization of rainbow trout, Oncorhynchus mykiss (Walbaum, 1792) stocks in India. Ashoktaru Barat Prabhati K. Sahoo Rohit Kumar Javaid I. Mir Shahnawaz Ali Rabindar S. Patiyal Atul K. Singh. Volume 94 Online resources 2015 pp e13- ...

  2. The effect of Cu2+ on osmoregulation in rainbow trout (Oncorhynchus mykiss) assayed by changes in plasma salinity and gill lipid metabolism

    DEFF Research Database (Denmark)

    Hansen, Heinz J.M.; Olsen, Allan Gylling; Rosenkilde, Per

    1993-01-01

    Zoofysiologi, Osmoregulation, Lipid metabolism, Ecotoxicology, Rainbow trout, Oncorhynchus mykiss.......Zoofysiologi, Osmoregulation, Lipid metabolism, Ecotoxicology, Rainbow trout, Oncorhynchus mykiss....

  3. A Practical Approach to Rainbow Trout (Oncorhynchus mykiss) Seed Production

    OpenAIRE

    , Orhan Çakır

    2002-01-01

    Rainbow trout (Oncorhynchus mykiss) grows faster and has great disease resistance. Therefore this species has been preferred to culture for years. Fry production, feeding and management of broodstock are explained practically in order to increase profitability.

  4. Vertebral column deformities in farmed rainbow trout ( Oncorhynchus mykiss )

    DEFF Research Database (Denmark)

    Madsen, Lone; Dalsgaard, Inger

    1999-01-01

    Farmed rainbow trout (Oncorhynchus mykiss) were fed diets with either different levels of vitamin C, or diets enriched with glucan or chitin, from feeding start and 6 months onwards. At an average weight of 100 g, the trout were X-rayed to determine the deformity level. The investigations showed...... of deformities (4.8%). In all groups examined, the deformities were spread over the whole vertebral column. The deformities in the group fed the low vitamin C diet were more severe than those found in the other groups. An outbreak of the disease rainbow trout fry syndrome (RTFS) caused by the bacterium...

  5. Molecular characterization of rainbow trout, Oncorhynchus mykiss ...

    Indian Academy of Sciences (India)

    Molecular Genetics Laboratory, Directorate of Coldwater Fisheries Research, Bhimtal 263 ... Mir J. I., Ali S., Patiyal R. S. and Singh A. K. 2015 Molecular characterization of rainbow trout, ..... 5 × 106 MCMC repeats for final sampling of data. .... enhancing aquaculture productivity in the coldwater regions. ... simulation study.

  6. Estrogenic response of bisphenol A in rainbow trout (Oncorhynchus mykiss)

    DEFF Research Database (Denmark)

    Lindholst, Christian; Pedersen, Knud Ladegaard; Pedersen, Søren Nørby

    2000-01-01

    Bisphenol A (BPA) previously shown to possess xenoestrogenic activities was administered to rainbow trout (Oncorhynchus mykiss) through a continuos flow system. The estrogenic response expressed as the induction of vitellogenin (VTG) synthesis was measured during 12 days of exposure, using a direct...

  7. Toxicokinetics of perfluorooctane sulfonate in rainbow trout (Oncorhynchus mykiss)

    Science.gov (United States)

    Rainbow trout (Oncorhynchus mykiss) confined to respirometer-metabolism chambers were dosed with perfluorooctane sulfonate (PFOS) by intra-arterial injection and sampled to obtain concentration time-course data for plasma, and either urine or expired water. The data were then an...

  8. Virulence of Flavobacterium columnare genomovars in rainbow trout Oncorhynchus mykiss.

    Science.gov (United States)

    Evenhuis, Jason P; LaFrentz, Benjamin R

    2016-08-09

    Flavobacterium columnare is the causative agent of columnaris disease and is responsible for significant economic losses in aquaculture. F. columnare is a Gram-negative bacterium, and 5 genetic types or genomovars have been described based on restriction fragment length polymorphism of the 16S rRNA gene. Previous research has suggested that genomovar II isolates are more virulent than genomovar I isolates to multiple species of fish, including rainbow trout Oncorhynchus mykiss. In addition, improved genotyping methods have shown that some isolates previously classified as genomovar I, and used in challenge experiments, were in fact genomovar III. Our objective was to confirm previous results with respect to genomovar II virulence, and to determine the susceptibility of rainbow trout to other genomovars. The virulence of 8 genomovar I, 4 genomovar II, 3 genomovar II-B, and 5 genomovar III isolates originating from various sources was determined through 3 independent challenges in rainbow trout using an immersion challenge model. Mean cumulative percent mortality (CPM) of ~49% for genomovar I isolates, ~1% for genomovar II, ~5% for the II-B isolates, and ~7% for the III isolates was observed. The inability of genomovar II isolates to produce mortalities in rainbow trout was unanticipated based on previous studies, but may be due to a number of factors including rainbow trout source and water chemistry. The source of fish and/or the presence of sub-optimal environment may influence the susceptibility of rainbow trout to different F. columnare genomovars.

  9. Diagnostic single nucleotide polymorphisms for identifying westslope cutthroat trout (Oncorhynchus clarki lewisi), Yellowstone cutthroat trout (Oncorhynchus clarkii bouvieri) and rainbow trout (Oncorhynchus mykiss).

    Science.gov (United States)

    Kalinowski, S T; Novak, B J; Drinan, D P; Jennings, R deM; Vu, N V

    2011-03-01

    We describe 12 diagnostic single nucleotide polymorphism (SNP) assays for use in species identification among rainbow and cutthroat trout: five of these loci have alleles unique to rainbow trout (Oncorhynchus mykiss), three unique to westslope cutthroat trout (O. clarkii lewisi) and four unique to Yellowstone cutthroat trout (O. clarkii bouvieri). These diagnostic assays were identified using a total of 489 individuals from 26 populations and five fish hatchery strains. © 2010 Blackwell Publishing Ltd.

  10. Gyrodactylid Ectoparasites in a Population of Rainbow Trout (Oncorhynchus mykiss)

    Science.gov (United States)

    Garcia, Rachel L; Hansen, Adam G; Chan, Maia M; Sanders, George E

    2014-01-01

    A colony of rainbow trout (Oncorhynchus mykiss) in a decentralized aquatic animal facility was noted to have an increase in morbidity and mortality (from 4 or 5 fish each month to 3 or 4 fish daily) approximately 2 wk after experimental procedures began. The primary clinical signs were erratic swimming behavior and ‘flashing’ of fish against surfaces within housing enclosures. Moribund and normal rainbow trout were presented alive for diagnostic evaluation; samples of water from housing enclosures were provided for water quality assessment. The trout were determined to be infected with gyrodactylids, a common monogenean ectoparasite of the skin and gills in both marine and freshwater fish. This case report describes the diagnosis, pathology, and treatment of gyrodactylids and husbandry modifications associated with the resolution of this clinical aquatic-animal case. PMID:24411786

  11. Muscle wound healing in rainbow trout (Oncorhynchus mykiss)

    DEFF Research Database (Denmark)

    Schmidt, Jacob Günther; Andersen, Elisabeth Wreford; Ersbøll, Bjarne Kjær

    2016-01-01

    We followed the progression of healing of deep excisional biopsy punch wounds over the course of 365 days in rainbow trout (Oncorhynchus mykiss) by monitoring visual wound healing and gene expression in the healing muscle at regular intervals (1, 3, 7, 14, 38 and 100 days post-wounding). In addit......We followed the progression of healing of deep excisional biopsy punch wounds over the course of 365 days in rainbow trout (Oncorhynchus mykiss) by monitoring visual wound healing and gene expression in the healing muscle at regular intervals (1, 3, 7, 14, 38 and 100 days post......-wounding). In addition, we performed muscle texture analysis one year after wound infliction. The selected genes have all previously been investigated in relation to vertebrate wound healing, but only few specifically in fish. The selected genes were interleukin (IL)-1β, IL-6, transforming growth factor (TGF)-β1 and -β3......, matrix metalloproteinase (MMP) -9 and -13, inducible nitric oxide synthase (iNOS), fibronectin (FN), tenascin-C (TN-C), prolyl 4-hydroxylase α1-chain (P4Hα1), lysyl oxidase (LOX), collagen type I α1-chain (ColIα1), CD41 and CD163. Wound healing progressed slowly in the presented study, which is at least...

  12. Estrogenic effect of dietary 4-tert-octylphenol in rainbow trout (Oncorhynchus mykiss)

    DEFF Research Database (Denmark)

    Pedersen, Kristine H; Pedersen, Søren N; Pedersen, Knud L

    2003-01-01

    The estrogenic effect of dietary 4-tert-octylphenol (octylphenol) in rainbow trout Oncorhynchus mykiss was investigated. Octylphenol was administered orally to sexually immature rainbow trout every second day for 11 days in doses between 0.4 and 50 mgkg(-1)2 d(-1). Plasma vitellogenin was measured...

  13. Experimental validation of geosmin uptake in rainbow trout, Oncorhynchus mykiss (Waldbaum) suggests biotransformation

    NARCIS (Netherlands)

    Schram, Edward; Schrama, Johan W.; Kooten, van Tobias; Kwadijk, Christiaan J.A.F.; Kampen, Harm; Kampen, Harm; Heul, van de Jan W.; Verreth, Johan A.J.; Murk, Albertinka J.

    2018-01-01

    The bioconcentration of waterborne geosmin in rainbow trout, Oncorhynchus mykiss (Waldbaum) was assessed. Fifty rainbow trout with a mean (SD) weight of 226.6 (29.0) g and lipid content of 6.2 (0.6) % (w/w) were exposed to geosmin in static water for 0, 2, 4, 6, 8, 12, 24, 36, 48 and 120 hr, with

  14. Case report of an unusual heart abnormality in Rainbow trout (Oncorhynchus mykiss)

    Science.gov (United States)

    An unusual heart abnormality in rainbow trout Oncorhynchus mykiss was recently observed. During the course of a standard hydrogen peroxide treatment (100 ppm) of production rainbow trout (mean weight, 2-3 g) affected with an external bacterial infection, a small percentage of fish exhibited morbidi...

  15. Genetic diversity in Chilean populations of rainbow trout, Oncorhynchus mykiss

    Directory of Open Access Journals (Sweden)

    Claudia B Cárcamo

    2015-03-01

    Full Text Available The rainbow trout Oncorhynchus mykiss, was first introduced in Chile between 1905 and 1920 and is currently widely distributed in Chile from Antofagasta (23°S to Patagonia (55°S. The broad range of the geographic and climatic distributions of this species in Chile offers a unique opportunity to study the effect of naturalization of an introduced species on its genetic variability. It is of particular importance to observe the genetic variability of populations in the northern range of this species distribution, in a transition zone where a Mediterranean-type climate changes to an arid climate. The present study analyzed allozymic variability and distribution within and between populations of O. mykiss from the river basins of Elqui and Limari rivers, and six culture strains, using starch-gel protein electrophoresis. Populations were found to be in Hardy-Weinberg equilibrium and the average values of He (0.045, polymorphism (13.9% and allele per locus (1.19 are similar to rainbow trout in its native distributional range. About 77.8% of the genetic variability was within population, similar to the variability reported for wild populations in the northern hemisphere. However, a marked genetic differentiation between wild populations was also found. This is likely to be the consequence of initial founder effects followed by subsequent introgression of resident populations caused by reseeding with trout of different origins in both basins.

  16. A novel role for pigment genes in the stress response in rainbow trout (Oncorhynchus mykiss)

    KAUST Repository

    Khan, Uniza Wahid; Ø verli, Ø yvind; Hinkle, Patricia M.; Pasha, Farhan Ahmad; Johansen, Ida Beitnes; Berget, Ingunn; Silva, Patricia I. M.; Kittilsen, Silje; Hö glund, Erik; Omholt, Stig W.; Vå ge, Dag Inge

    2016-01-01

    pigmentation gene, melanocyte stimulating hormone receptor (MC1R), is strongly associated with distinct differences in steroidogenic melanocortin 2 receptor (MC2R) mRNA expression between high- (HR) and low-responsive (LR) rainbow trout (Oncorhynchus mykiss

  17. BIOACCUMULATION AND ENANTIOSELECTIVE BIOTRANSFORMATION OF FIPRONIL BY RAINBOW TROUT (ONCORHYNCHUS MYKISS)

    Science.gov (United States)

    Dietary accumulation and enantioselective biotransformation was determined for rainbow trout (Oncorhynchus mykiss) exposed to fipronil, a widely used chiral pesticide. Measurement of the fish carcass tissue (whole fish minus GI tract and liver) showed a rapid accumulation of fip...

  18. Estrogenic Activity of Perfluoroalkyl Acids in Juvenile Rainbow Trout (Oncorhynchus Mykiss)

    Science.gov (United States)

    The potential estrogenic activity of perfluoroalkyl acids (PFAAs) was determined using separate screening and dose response studies with juvenile rainbow trout (Oncorhynchus mykiss). Results of this study indicate that some PFAAs may act as estrogens in fish.

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

    Science.gov (United States)

    Page, G I; Davies, S J

    2006-01-01

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

  20. Experimental evaluation of rainbow trout Oncorhynchus mykiss predation on longnose dace Rhinichthys cataractae

    Science.gov (United States)

    Turek, Kelly C.; Pegg, Mark A.; Pope, Kevin L.

    2014-01-01

    Laboratory and in-stream enclosure experiments were used to determine whether rainbow trout Oncorhynchus mykiss influence survival of longnose dace Rhinichthys cataractae. In the laboratory, adult rainbow trout preyed on longnose dace in 42% of trials and juvenile rainbow trout did not prey on longnose dace during the first 6 h after rainbow trout introduction. Survival of longnose dace did not differ in the presence of adult rainbow trout previously exposed to active prey and those not previously exposed to active prey ( = 0.28, P = 0.60). In field enclosures, the number of longnose dace decreased at a faster rate in the presence of rainbow trout relative to controls within the first 72 h, but did not differ between moderate and high densities of rainbow trout (F2,258.9 = 3.73, P = 0.03). Additionally, longnose dace were found in 7% of rainbow trout stomachs after 72 h in enclosures. Rainbow trout acclimated to the stream for longer periods had a greater initial influence on the number of longnose dace remaining in enclosures relative to those acclimated for shorter periods regardless of rainbow trout density treatment (F4,148.5 = 2.50, P = 0.04). More research is needed to determine how predation rates will change in natural environments, under differing amounts of habitat and food resources and in the context of whole assemblages. However, if rainbow trout are introduced into the habitat of longnose dace, some predation on longnose dace is expected, even when rainbow trout have no previous experience with active prey.

  1. Sensory analysis of rainbow trout, oncorhynchus mykiss, fed enriched black soldier fly prepupae, hermetia illucens

    Science.gov (United States)

    A growth trial and fillet sensory analysis were conducted to examine the effects of replacing dietary fish meal with black soldier fly (BSF) prepupae, Hermetia illucens, in rainbow trout, Oncorhynchus mykiss. A practical-type trout diet was formulated to contain 45% protein; four test diets were dev...

  2. Subunit vaccine candidates against Aeromonas salmonicida in rainbow trout Oncorhynchus mykiss

    DEFF Research Database (Denmark)

    Marana, Moonika Haahr; Jørgensen, Louise von Gersdorff; Skov, Jakob

    2017-01-01

    rainbow trout (Oncorhynchus mykiss, Walbaum) aquaculture furunculosis outbreaks still occur. In this study we tested the efficacy of experimental subunit vaccines against A. salmonicida infection in rainbow trout. We utilized in silico screening of the proteome of A. salmonicida subsp. salmonicida strain...... A449 and identified potential protective protein antigens that were tested by in vivo challenge trial. A total of 14 proteins were recombinantly expressed in Escherichia coli and prepared in 3 different subunit vaccine combinations to immunize 3 groups of rainbow trout by intraperitoneal (i...

  3. Muscle wound healing in rainbow trout (Oncorhynchus mykiss).

    Science.gov (United States)

    Schmidt, J G; Andersen, E W; Ersbøll, B K; Nielsen, M E

    2016-01-01

    We followed the progression of healing of deep excisional biopsy punch wounds over the course of 365 days in rainbow trout (Oncorhynchus mykiss) by monitoring visual wound healing and gene expression in the healing muscle at regular intervals (1, 3, 7, 14, 38 and 100 days post-wounding). In addition, we performed muscle texture analysis one year after wound infliction. The selected genes have all previously been investigated in relation to vertebrate wound healing, but only few specifically in fish. The selected genes were interleukin (IL)-1β, IL-6, transforming growth factor (TGF)-β1 and -β3, matrix metalloproteinase (MMP) -9 and -13, inducible nitric oxide synthase (iNOS), fibronectin (FN), tenascin-C (TN-C), prolyl 4-hydroxylase α1-chain (P4Hα1), lysyl oxidase (LOX), collagen type I α1-chain (ColIα1), CD41 and CD163. Wound healing progressed slowly in the presented study, which is at least partially due to the low temperature of about 8.5 °C during the first 100 days. The inflammation phase lasted more than 14 days, and the genes relating to production and remodeling of new extracellular matrix (ECM) exhibited a delayed but prolonged upregulation starting 1-2 weeks post-wounding and lasting until at least 100 days post-wounding. The gene expression patterns and histology reveal limited capacity for muscle regeneration in rainbow trout, and muscle texture analyses one year after wound infliction confirm that wounds heal with fibrosis. At 100 dpw epidermis had fully regenerated, and dermis partially regenerated. Scales had not regenerated even after one year. CD163 is a marker of "wound healing"-type M2c macrophages in mammals. M2 macrophage markers are as yet poorly described in fish. The pattern of CD163 expression in the present study is consistent with the expected timing of presence of M2c macrophages in the wound. CD163 may thus potentially prove a valuable marker of M2 macrophages - or a subset hereof - in fish. We subjected a group of fish to

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

    Science.gov (United States)

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

    2013-11-25

    Tetracapsuloides bryosalmonae (Myxozoa) is the causative agent of proliferative kidney disease in salmonids. We assessed differences in intensity of T. bryosalmonae infection between brown trout Salmo trutta and rainbow trout Oncorhynchus mykiss from the clinical phase of infection onwards. Specific pathogen-free fish were exposed to T. bryosalmonae spores under controlled laboratory conditions and sampled at 6, 8, 10, 12, 14, and 17 wk post exposure (wpe), and the transmission of T. bryosalmonae from infected fish to the bryozoan Fredericella sultana was observed. Parasite load was determined in fish kidneys by quantitative real-time PCR (qRT-PCR), and parasite stages were detected in kidney, liver, and spleen tissues at different time points by immunohistochemistry. T. bryosalmonae was successfully transmitted from infected brown trout to F. sultana colonies but not from infected rainbow trout. Body length and weight of infected brown trout did not differ significantly from control brown trout during all time points, while length and weight of infected rainbow trout differed significantly compared to controls from 10 to 17 wpe. qRT-PCR revealed that parasite load was significantly higher in kidneys of brown trout compared with rainbow trout. Immunohistochemistry showed high numbers of intra-luminal stages (sporogonic stages) in kidneys of brown trout with low numbers of pre-sporogonic stages. Sporogonic stages were not seen in kidneys of rainbow trout; only high numbers of pre-sporogonic stages were detected. Numbers of pre-sporogonic stages were low in the spleen and liver of brown trout but high in rainbow trout. These data confirmed that there are differences in the development and infection progress of T. bryosalmonae between brown trout and rainbow trout.

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

    Science.gov (United States)

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

    2014-01-01

    Tetracapsuloides bryosalmonae (Myxozoa) is the causative agent of proliferative kidney disease in salmonids. We assessed differences in intensity of T. bryosalmonae infection between brown trout Salmo trutta and rainbow trout Oncorhynchus mykiss from the clinical phase of infection onwards. Specific pathogen-free fish were exposed to T. bryosalmonae spores under controlled laboratory conditions and sampled at 6, 8, 10, 12, 14, and 17 wk post exposure (wpe), and the transmission of T. bryosalmonae from infected fish to the bryozoan Fredericella sultana was observed. Parasite load was determined in fish kidneys by quantitative real-time PCR (qRT-PCR), and parasite stages were detected in kidney, liver, and spleen tissues at different time points by immunohistochemistry. T. bryosalmonae was successfully transmitted from infected brown trout to F. sultana colonies but not from infected rainbow trout. Body length and weight of infected brown trout did not differ significantly from control brown trout during all time points, while length and weight of infected rainbow trout differed significantly compared to controls from 10 to 17 wpe. qRT-PCR revealed that parasite load was significantly higher in kidneys of brown trout compared with rainbow trout. Immunohistochemistry showed high numbers of intra-luminal stages (sporogonic stages) in kidneys of brown trout with low numbers of pre-sporogonic stages. Sporogonic stages were not seen in kidneys of rainbow trout; only high numbers of pre-sporogonic stages were detected. Numbers of pre-sporogonic stages were low in the spleen and liver of brown trout but high in rainbow trout. These data confirmed that there are differences in the development and infection progress of T. bryosalmonae between brown trout and rainbow trout. PMID:24270019

  6. Effects of Temperature on Production and Specificity of Antibodies in Rainbow Trout (Oncorhynchus mykiss)

    DEFF Research Database (Denmark)

    Mikkelsen, Heidi; Nielsen, Michael Engelbrecht; Lindenstrom, Thomas

    2006-01-01

    The effect of temperature on production and affinity of antibodies against antigens from the parasitic ciliate Ichthyophthirius multifiliis were studied in rainbow trout (Oncorhynchus mykiss). Fish were immunized with I. multifiliis antigens and reared at three different temperatures, 5, 12, and 20...... reared at 5 C was similar to fish reared at 12 and 20 C. However, when samples were assayed at 12 and 20 C, the measured antibody response tended to be higher for the samples from trout reared at 12 and 20 C. Additionally, it was found that rainbow trout reared at 5 C showed a delayed but not hampered...

  7. Effect of frozen storage temperature on quality-related changes in rainbow trout (Oncorhynchus mykiss)

    DEFF Research Database (Denmark)

    Burgaard, Maria Garver; Jørgensen, Bo M.

    2011-01-01

    The effect of frozen storage temperature on quality-related parameters of rainbow trout (Oncorhynchus mykiss) muscle was studied in the interval from -10 to -80°C on samples stored for 1 to 18 months. The following quantities were measured: drip loss, water holding capacity and water distribution...

  8. Observations on side-swimming rainbow trout Oncorhynchus mykiss in water recirculation aquaculture systems

    Science.gov (United States)

    During a controlled 6-month study using six replicated water recirculation aquaculture systems (WRAS), it was observed that rainbow trout Oncorhynchus mykiss in all WRAS exhibited a higher-than-normal prevalence of side-swimming (i.e. controlled, forward swimming, but with misaligned orientation suc...

  9. Behavioral plasticity in rainbow trout ( Oncorhynchus mykiss ) with divergent coping styles: When doves become hawks

    DEFF Research Database (Denmark)

    Ruiz-Gomez, M.de Lourdes; Kittilsen, S.; Höglund, Erik

    2008-01-01

    Consistent and heritable individual differences in reaction to challenges, often referred to as stress coping styles, have been extensively documented invertebrates. In fish, selection for divergent post-stress plasma Cortisol levels in rainbow trout (Oncorhynchus mykiss) has yielded a low (LR) a...

  10. Excess posthypoxic oxygen consumption in rainbow trout (Oncorhynchus mykiss): recovery in normoxia and hypoxia

    DEFF Research Database (Denmark)

    Svendsen, Jon Christian; Steffensen, John Fleng; Aarestrup, Kim

    2012-01-01

    at which the standard metabolic rate becomes dependent upon the ambient oxygen content. Using rainbow trout (Oncorhynchus mykiss (Walbaum, 1792), this study quantified the excess posthypoxic oxygen consumption (EPHOC) occurring after exposure to oxygen availability below S(crit). Tests showed that S...

  11. Retinal processing and opponent mechanisms mediating ultraviolet polarization sensitivity in rainbow trout (Oncorhynchus mykiss)

    NARCIS (Netherlands)

    Ramsden, Samuel D.; Anderson, Leslie; Mussi, Martina; Kamermans, Maarten; Hawryshyn, Craig W.

    2008-01-01

    A number of teleost fishes have photoreceptor mechanisms to detect linearly polarized light. We studied the neuronal mechanism underlying this ability. It was found that a polarized signal could be detected in rainbow trout (Oncorhynchus mykiss) both in the electroretinogram (ERG) and in the

  12. Use of streambed substrate as refuge by steelhead or rainbow trout Oncorhynchus mykiss during simulated freshets

    Science.gov (United States)

    F. K. Ligon; Rodney Nakamoto; Bret Harvey; P. F. Baker

    2016-01-01

    A flume was used to estimate the carrying capacity of streambed substrates for juvenile steelhead or rainbow trout Oncorhynchus mykiss seeking refuge from simulated freshets. The simulated freshets had mean water column velocities of c. 1·1 m s−1. The number of O. mykiss finding cover...

  13. Novel molecular markers differentiate Oncorhynchus mykiss (rainbow trout and steelhead) and the O. clarki (cutthroat trout) subspecies

    Science.gov (United States)

    Ostberg, C.O.; Rodriguez, R.J.

    2002-01-01

    A suite of 26 PCR-based markers was developed that differentiates rainbow (Oncorhynchus mykiss) and coastal cutthroat trout (O. clarki clarki). The markers also differentiated rainbow from other cutthroat trout subspecies (O. clarki), and several of the markers differentiated between cutthroat trout subspecies. This system has numerous positive attributes, including: nonlethal sampling, high species-specificity and products that are easily identified and scored using agarose gel electrophoresis. The methodology described for developing the markers can be applied to virtually any system in which numerous markers are desired for identifying or differentiating species or subspecies.

  14. A second generation genetic map for rainbow trout (Oncorhynchus mykiss

    Directory of Open Access Journals (Sweden)

    Gahr Scott A

    2008-11-01

    Full Text Available Abstract Background Genetic maps characterizing the inheritance patterns of traits and markers have been developed for a wide range of species and used to study questions in biomedicine, agriculture, ecology and evolutionary biology. The status of rainbow trout genetic maps has progressed significantly over the last decade due to interest in this species in aquaculture and sport fisheries, and as a model research organism for studies related to carcinogenesis, toxicology, comparative immunology, disease ecology, physiology and nutrition. We constructed a second generation genetic map for rainbow trout using microsatellite markers to facilitate the identification of quantitative trait loci for traits affecting aquaculture production efficiency and the extraction of comparative information from the genome sequences of model fish species. Results A genetic map ordering 1124 microsatellite loci spanning a sex-averaged distance of 2927.10 cM (Kosambi and having 2.6 cM resolution was constructed by genotyping 10 parents and 150 offspring from the National Center for Cool and Cold Water Aquaculture (NCCCWA reference family mapping panel. Microsatellite markers, representing pairs of loci resulting from an evolutionarily recent whole genome duplication event, identified 180 duplicated regions within the rainbow trout genome. Microsatellites associated with genes through expressed sequence tags or bacterial artificial chromosomes produced comparative assignments with tetraodon, zebrafish, fugu, and medaka resulting in assignments of homology for 199 loci. Conclusion The second generation NCCCWA genetic map provides an increased microsatellite marker density and quantifies differences in recombination rate between the sexes in outbred populations. It has the potential to integrate with cytogenetic and other physical maps, identifying paralogous regions of the rainbow trout genome arising from the evolutionarily recent genome duplication event, and

  15. Seasonal Variations in Relative Weight of Lake Trout (Salvelinus namaycush), Kokanee Salmon (Oncorhynchus nerka), Rainbow Trout (Onocorhynchus mykiss), and Brown Trout (Salmo trutta) in Blue Mesa Reservoir, Colorado

    OpenAIRE

    Midas, Madeline; Williams, Asia; Cooper, Cindy; Courtney, Michael

    2013-01-01

    Blue Mesa Reservoir is the largest body of water in Colorado and is located on the western slope of the Rocky Mountains at an elevation of 7520 feet. Blue Mesa Reservoir contains recreationally important populations of lake trout (Salvelinus namaycush), kokanee salmon (Oncorhynchus nerka), rainbow trout (Onocorhynchus mykiss), and brown trout (Salmo trutta). A management challenge in recent years has been the overpopulation of lake trout, which has led to a steep decline in abundance of kokan...

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

    OpenAIRE

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

    2013-01-01

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

  17. Flavobacterium psychrophilum, invasion into and shedding by rainbow trout Oncorhynchus mykiss

    DEFF Research Database (Denmark)

    Madetoja, J.; Nyman, P.; Wiklund, T.

    2000-01-01

    The infection route of Flavobacterium psychrophilum into rainbow trout Oncorhynchus mykiss was studied using bath and cohabitation challenges as well as oral challenge with live feed as a vector. Additionally, the number of bacterial cells shed by infected fish into the surrounding water...... is discussed as an important invasion route for F. psychrophilum into the fish. The shedding rate of F. psychrophiIlun by infected fish was associated with water temperature and the mortality of the infected fish. High numbers of F. psychrophilum cells were released into the water by dead rainbow trout during...

  18. Staphylococcus warneri, a resident skin commensal of rainbow trout (Oncorhynchus mykiss) with pathobiont characteristics.

    Science.gov (United States)

    Musharrafieh, Rami; Tacchi, Luca; Trujeque, Joshua; LaPatra, Scott; Salinas, Irene

    2014-02-21

    Commensal microorganisms live in association with the mucosal surfaces of all vertebrates. The skin of teleost fish is known to harbor commensals. In this study we report for the first time the presence of an intracellular Gram positive bacteria, Staphylococcus warneri that resides in the skin epidermis of rainbow trout (Oncorhynchus mykiss). S. warneri was isolated from healthy hatchery trout skin epithelial cells. In situ hybridization confirmed the intracellular nature of the bacterium. Skin explants exposed in vitro to S. warneri or the extracellular pathogen Vibrio anguillarum show that S. warneri is able to induce an anti-inflammatory cytokine status via TGF-β1b compared to the pro-inflammatory responses (IL-1β, IL-6 and TNF-∝) elicited by V. anguillarum. In vivo experiments showed that S. warneri is not pathogenic to rainbow trout when injected intraperitoneally at high concentrations. However, S. warneri is able to stimulate V. anguillarum growth and biofilm formation on rainbow trout scales. Our results demonstrate that rainbow trout skin commensals such as S. warneri have the potential to become indirect pathobionts by enhancing growth and biofilm formation of pathogens such as V. anguillarum. These results show that fish farming practices (i.e. handling and other manipulations) can alter the skin microbiota and compromise the skin health of rainbow trout. Copyright © 2013 Elsevier B.V. All rights reserved.

  19. Comparison of biochemical parameters of rainbow trout (Oncorhynchus mykiss) reared in two different trout farms'

    Science.gov (United States)

    Karatas, Tayfun

    2016-04-01

    The aim of this study was to compare biochemical parameters of cultured rainbow trouts (Oncorhynchus mykiss, Walbaum, 1972) reared in two different trout farms' (Agri and Erzurum). The average weights of fish were 150±10gr for first station (Agri), 230±10gr for second station (Erzurum). Fishes used in research were randomly caught from pools, and fifteen pieces were used for each group. Fishes were fed with commercial trout feed with 45-50% crude protein twice a day. The levels of AST, ALT, LDL, total cholesterol and triglyceride in the second station (Erzurum) were found to be higher (p<0.05) than that of first station (Agri). Whereas, the levels of HDL in the second station (Erzurum) were found to be lower (p<0.05) than that of first station (Agri). Differences in the levels of total cholesterol and AST, ALT, HDL, LDL, triglyceride may be associated with size, sex, sexual maturity and environmental conditions (temperature, pH, hardness and dissolved oxygen).

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

    Directory of Open Access Journals (Sweden)

    Helena Hauge

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

  1. Challenge models for RTFS in rainbow trout fry (Oncorhynchus mykiss)

    DEFF Research Database (Denmark)

    Henriksen, Maya Maria Mihályi; Madsen, Lone; Dalsgaard, Inger

    2011-01-01

    forms of stress have shown to be reproducible. Bath challenge is more appropriate for vaccine testing, since natural transmission of infection is imitated and is also more suitable due to the small size of the fry. A bath-model using H2O2 as a stressor is currently being tested on 1.4g rainbow trout fry...... in four experimental groups: 1) no H2O2/no bath infection, 2) H2O2/no bath infection, 3) no H2O2/ bath infection and 4) H2O2/ bath infection. Mortality will be evaluated over approximately 25 days. The project is currently in its preliminary phase and presently focused on development of a model...

  2. Assessment of ranges plasma indices in rainbow trout (Oncorhynchus mykiss) reared under conditions of intensive aquaculture

    OpenAIRE

    Radovan Kopp; Jan Mareš; Štěpán Lang; Tomáš Brabec; Andrea Ziková

    2011-01-01

    Plasma parameters in rainbow trout (Oncorhynchus mykiss) from three various trout farms in the Czech Republic were assessed using automated blood plasma analyser. Non-haemolysed serum from the heart of 48 healthy, randomly selected fish (standard length, mean ± SD = 247.3 ± 24.2 mm; body mass, mean ± SD = 262.18 ± 87.28 g) was analysed for the following plasma parameters: alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, acid phosphatase, lactate dehydrogenase, creat...

  3. Identification of Estrogen-responsive Vitelline Envelope Protein Fragments from Rainbow Trout (Oncorhynchus mykiss) Plasma Using Mass Spectrometry

    Science.gov (United States)

    Plasma protein biomarkers associated with exposure of rainbow trout (Oncorhynchus mykiss) to 17β-estradiol were isolated and identified using novel sample preparation techniques and state-of-the-art mass spectrometry and bioinformatics approaches. Juvenile male and female trout ...

  4. Experimental infection of rainbow trout Oncorhynchus mykiss with viral haemorrhagic septicaemia virus isolates from European marine and farmed fishes

    DEFF Research Database (Denmark)

    Skall, Helle Frank; Slierendrecht, W.J.; King, J.A.

    2004-01-01

    The susceptibility of rainbow trout Oncorhynchus mykiss to infection with various isolates of viral haemorrhagic septicaemia virus (VHSV) was examined. A total of 8 experiments with rainbow trout ranging from 0.6 to 6.2 g was conducted for 139 isolates originating from wild marine fishes in Europ......The susceptibility of rainbow trout Oncorhynchus mykiss to infection with various isolates of viral haemorrhagic septicaemia virus (VHSV) was examined. A total of 8 experiments with rainbow trout ranging from 0.6 to 6.2 g was conducted for 139 isolates originating from wild marine fishes...... in European waters (115 isolates), farmed turbot from Scotland and Ireland (2 isolates), and farmed rainbow trout (22 isolates). The isolates were tested by immersion and/or intraperitoneal injection either as pooled or single isolates. The isolates from wild marine fishes did not cause mortality by immersion...... while some of the isolates caused mortality when injected. All VHSV isolates from farmed rainbow trout caused significant mortality by immersion. Currently, pathogenicity trials are the only way to differentiate VHSV isolates from wild marine fishes and farmed rainbow trout. The 2 farmed turbot isolates...

  5. Biomagnification and tissue distribution of perfluoroalkyl substances (PFASs) in market-size rainbow trout (Oncorhynchus mykiss).

    Science.gov (United States)

    Goeritz, Ina; Falk, Sandy; Stahl, Thorsten; Schäfers, Christoph; Schlechtriem, Christian

    2013-09-01

    The present study investigated the biomagnification potential as well as the substance and tissue-specific distribution of perfluoroalkyl substances (PFASs) in market-size rainbow trout (Oncorhynchus mykiss). Rainbow trout with an average body weight of 314 ± 21 g were exposed to perfluorobutane sulfonate (PFBS), perfluorohexane sulfonate (PFHxS), perfluorooctane sulfonate (PFOS), perfluorooctanoic acid (PFOA), and perfluorononanoic acid (PFNA) in the diet for 28 d. The accumulation phase was followed by a 28-d depuration phase, in which the test animals were fed with nonspiked trout feed. On days 0, 7, 14, 28, 31, 35, 42, and 56 of the present study, fish were sampled from the test basin for PFAS analysis. Biomagnification factors (BMFs) for all test compounds were determined based on a kinetic approach. Distribution factors were calculated for each test compound to illustrate the disposition of PFASs in rainbow trout after 28 d of exposure. Dietary exposure of market-size rainbow trout to PFASs did not result in biomagnification; BMF values were calculated as 0.42 for PFOS, >0.23 for PFNA, >0.18 for PFHxS, >0.04 for PFOA, and >0.02 for PFBS, which are below the biomagnification threshold of 1. Liver, blood, kidney, and skin were identified as the main target tissues for PFASs in market-size rainbow trout. Evidence was shown that despite relative low PFAS contamination, the edible parts of the fish (the fillet and skin) can significantly contribute to the whole-body burden. Copyright © 2013 SETAC.

  6. Cannibalism in non-native brown trout Salmo trutta and rainbow trout Oncorhynchus mykiss stream-dwelling populations.

    Science.gov (United States)

    Musseau, C; Vincenzi, S; Jesenšek, D; Crivelli, A J

    2017-12-01

    Introduced and allopatric populations of brown trout Salmo trutta and rainbow trout Oncorhynchus mykiss were sampled in Slovenia for stable isotope analysis to assess dietary niche shifts through ontogeny and estimate the propensity for cannibalism. Both S. trutta and O. mykiss are cannibals, with higher average relative contribution of conspecific assimilated energy for S. trutta (27·9%) compared with O. mykiss (7·7%). The smallest cannibal was 166 mm in the S. trutta population and 247 mm in the O. mykiss population. © 2017 The Fisheries Society of the British Isles.

  7. Comparative toxicity of four crude oils to the early life stages of rainbow trout (Oncorhynchus mykiss)

    International Nuclear Information System (INIS)

    Clarke, L.M.J.; Khan, C.W.; Akhtar, P.; Hodson, P.V.; Short, J.W.

    2004-01-01

    Crude oil is a source of polycyclic aromatic hydrocarbons (PAH) in aquatic ecosystems. Fish that are chronically exposed to alkyl PAHs show dioxin-like toxicity characterized by the presence of blue sac disease (BSD) and the induction of cytochrome P4501A (CYP1A). This study compared the relative toxicity of four crude oils (Scotian Light Crude, MESA, the synthetic Federated Crude, and Alaska North Slope Crude) to early life stages of rainbow trout (Oncorhynchus mykiss). The study examined the influence of the four crudes in causing the disease in rainbow trout embryos living in simulated spawning beds with hydrocarbon-contaminated gravel. Each oil had different chemical characteristics and PAH concentrations. Mortality in the direct exposure experiment increased as the oil concentration increased. The same trend was observed for the BSD prevalence. The study showed that Scotian Light Crude was the least toxic, with BSD increasing only at the highest concentration. 7 refs., 2 tabs., 1 fig

  8. PAMP INDUCED EXPRESSION OF IMMUNE RELEVANT GENES IN HEAD KIDNEY LEUKOCYTES OF RAINBOW TROUT (ONCORHYNCHUS MYKISS)

    DEFF Research Database (Denmark)

    Chettri, Jiwan Kumar; Holten-Andersen, Lars; Kania, Per Walter

    mykiss) to different PAMPs mimicking bacterial (flagellin and LPS), viral (poly I:C) and fungal infections (zymosan and ß-glucan). Transcript of cytokines related to inflammation (IL-1ß, IL-6, IL-10 and TNF-a) were highly up-regulated following LPS exposure whereas flagellin or poly I:C induced merely...... of the invader. Phagocytic cells are known to initiate a respiratory burst following an exposure to the pathogen, but the underlying and associated specific elements are poorly elucidated in fish. The present study describes the differential response of head kidney leukocytes from rainbow trout (Oncorhynchus...... of LPS and zymosan became evident after 4 h exposure. This study suggests that rainbow trout leukocytes respond differently to viral, bacterial and fungal PAMPs, which may reflect activation of specific signaling cascades eventually leading to activation of different immune effector molecules....

  9. Cadmium affects the social behaviour of rainbow trout, Oncorhynchus mykiss

    International Nuclear Information System (INIS)

    Sloman, Katherine A.; Scott, Graham R.; Diao Zhongyu; Rouleau, Claude; Wood, Chris M.; McDonald, D. Gord

    2003-01-01

    The present study investigated both the effects of cadmium on the social interactions of rainbow trout and the differential accumulation of waterborne cadmium among social ranks of fish. Fish exposed to waterborne cadmium concentrations of 2 μg l -1 for 24 h, followed by a 1, 2 or 3 day depuration period in clean water, had a decreased ability to compete with non-exposed fish. However, the competitive ability of exposed fish given a 5 day depuration period was not significantly impaired. Cadmium accumulated in the olfactory apparatus of fish exposed to waterborne cadmium for 24 h and decreased significantly only after 5 days depuration in clean water. Among groups of ten fish held in stream tanks, where all fish were exposed to cadmium, there were significant effects on social behaviour and growth rate. Dominance hierarchies formed faster among fish exposed to cadmium than among control fish, and overall growth rates were higher in the cadmium treatment. In groups of ten fish, social status also affected tissue accumulation of cadmium during waterborne exposure, with dominant fish accumulating more cadmium at the gill. In conclusion, exposure to low levels of cadmium, affects the social behaviour of fish, in part due to accumulation in the olfactory apparatus, and dominant fish accumulate more gill cadmium than subordinates during chronic waterborne exposure

  10. Whole body and tissue blood volumes of two strains of rainbow trout (Oncorhynchus mykiss)

    Science.gov (United States)

    Gingerich, W.H.; Pityer, R.A.; Rach, J.J.

    1990-01-01

    1. Estimates of apparent packed cell, plasma and total blood volumes for the whole body and for 13 selected tissues were compared between Kamloops and Wytheville strains of rainbow trout (Oncorhynchus mykiss) by the simultaneous injection of two vascular tracers, radiolabeled trout erythrocytes (51Cr-RBC) and radioiodated bovine serum albumin (125I-BSA).2. Whole body total blood volume, plasma volume and packed cell volume were slightly, but not significantly greater in the Wytheville trout, whereas, the apparent plasma volumes and total blood volumes in 4 of 13 tissues were significantly greater in the Kamloops strain.3. Differences were most pronounced in highly perfused organs, such as the liver and kidney and in organs of digestion such as the stomach and intestines.4. Differences in blood volumes between the two strains may be related to the greater permeability of the vascular membranes in the Kamloops strain fish.

  11. Prophylactic effect of levamisole on rainbow trout (Oncorhynchus mykiss against Yersinia ruckeri

    Directory of Open Access Journals (Sweden)

    Unal Ispir

    2009-09-01

    Full Text Available Alteration in the relative percentage of survival (RPS rate of rainbow trout (Oncorhynchus mykiss exposed to 5, 10 and 25µg ml-1 levamisole for 2 h against Yersinia ruckeri was investigated. The average weight of the 120 fish used in this study was 6.3g. Upon challenge with a virulent strain, the relative survival percentage of respectively 83.3%, 86.7% and 76.6% was recorded. The results suggest that the application of levamisole in fish farms could increase resistance to infection of fish and offer economic benefits.

  12. Contribution to the definition of the metabolic profile of farmed rainbow trout (Oncorhynchus mykiss

    Directory of Open Access Journals (Sweden)

    Massimo Mecatti

    2010-01-01

    Full Text Available The haematic outline of 339 rainbow trout (Oncorhynchus mykissfrom two different farms in the Lucca province was studied for a preliminary assessment of the metabolic profile of this species and for the investigation of the influence of some endogenous and exogenous factors on the variability of the studied parameters. The sampling time, as well as the weight, appears to have caused significant variations on most of the parameters analysed. The present study gives the annual means and the seasonal trends for each farm where the study was carried out.

  13. Mechanisms of fenthion activation in rainbow trout (Oncorhynchus mykiss) acclimated to hypersaline environments

    International Nuclear Information System (INIS)

    Lavado, Ramon; Rimoldi, John M.; Schlenk, Daniel

    2009-01-01

    Previous studies in rainbow trout have shown that acclimation to hypersaline environments enhances the toxicity to thioether organophosphate and carbamate pesticides. In order to determine the role of biotransformation in this process, the metabolism of the thioether organophosphate biocide, fenthion was evaluated in microsomes from gills, liver and olfactory tissues in rainbow trout (Oncorhynchus mykiss) acclimated to freshwater and 17 per mille salinity. Hypersalinity acclimation increased the formation of fenoxon and fenoxon sulfoxide from fenthion in liver microsomes from rainbow trout, but not in gills or in olfactory tissues. NADPH-dependent and independent hydrolysis was observed in all tissues, but only NADPH-dependent fenthion cleavage was differentially modulated by hypersalinity in liver (inhibited) and gills (induced). Enantiomers of fenthion sulfoxide (65% and 35% R- and S-fenthion sulfoxide, respectively) were formed in liver and gills. The predominant pathway of fenthion activation in freshwater appears to be initiated through initial formation of fenoxon which may be subsequently converted to the most toxic metabolite fenoxon R-sulfoxide. However, in hypersaline conditions both fenoxon and fenthion sulfoxide formation may precede fenoxon sulfoxide formation. Stereochemical evaluation of sulfoxide formation, cytochrome P450 inhibition studies with ketoconazole and immunoblots indicated that CYP3A27 was primarily involved in the enhancement of fenthion activation in hypersaline-acclimated fish with limited contribution of FMO to initial sulfoxidation

  14. Evaluation of a rainbow trout (Oncorhynchus mikyss culture water recirculating system

    Directory of Open Access Journals (Sweden)

    Iván Sánchez O.

    2014-09-01

    Full Text Available Objective. To evaluate a water recirculation system for rainbow trout fish cultures at the recirculating laboratory of the Aquaculture Engineering Production Program of University of Nariño. Materials and Methods. 324 rainbow trout (Oncorhynchus mikyss fries were cultured in 12 plastic tanks with a capacity of 250 L in an aquaculture recirculating system the treatment system of which was made up by a conventional sedimentation tank, a fixed stand upflow biofilter with recycled PVC tube pieces and a natural degassing system; the sedimentation unit effluent was pumped up to a reservoir tank using a 2 HP centrifugal pump after being subject to gravity through the biofilter and to be then distributed to the 12 culture units to which a constant amount of air from a blower was injected. Results. The water treatment system removed 31% of total suspended solids, 9.5% of total ammonia nitrogen, and increased dissolved oxygen to the final effluent in 6.5%. An increase of 305% in biomass was calculated during 75 days, the mortality percentage registered throughout the study period was 4.9%. Conclusions. The water treatment system maintained the physicochemical water quality parameters within the values recommended for the species. The increase in weight and size, food conversion, mortality and biomass production reported normal values for rainbow trout fish culture in recirculating systems.

  15. Rainbow trout (Oncorhynchus mykiss) detection, avoidance, and chemosensory effects of oil sands process-affected water.

    Science.gov (United States)

    Lari, Ebrahim; Pyle, Greg G

    2017-06-01

    Oil sands process-affected water (OSPW) - a byproduct of the oil sands industry in Northern Alberta, Canada - is currently stored in on-site tailings ponds. The goal of the present study was to investigate the interaction of OSPW with the olfactory system and olfactory-mediated behaviours of fish upon the first encounter with OSPW. The response of rainbow trout (Oncorhynchus mykiss) to different concentrations (0.1, 1, and 10%) of OSPW was studied using a choice maze and electro-olfactography (EOG), respectively. The results of the present study showed that rainbow trout are capable of detecting and avoiding OSPW at a concentration as low as 0.1%. Exposure to 1% OSPW impaired (i.e. reduced sensitivity) the olfactory response of rainbow trout to alarm and food cues within 5 min or less. The results of the present study demonstrated that fish could detect and avoid minute concentrations of OSPW. However, if fish were exposed to OSPW-contaminated water and unable to escape, their olfaction would be impaired. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Immune responses to methanolic extract of black cumin (Nigella sativa) in rainbow trout (Oncorhynchus mykiss).

    Science.gov (United States)

    Celik Altunoglu, Yasemin; Bilen, Soner; Ulu, Ferhat; Biswas, Gouranga

    2017-08-01

    The immune stimulating effects of the methanolic extract of black cumin (Nigella sativa) in rainbow trout (Oncorhynchus mykiss) was evaluated. Variable concentrations of black cumin methanolic extract [0 (Control), 0.1 and 0.5 g kg -1 of feed] were individually added to the basal diet and rainbow trout was fed for 30 days to assess the innate immune responses and growth performance. Feed conversion ratio significantly decreased in the group fed with 0.5 g kg -1 black cumin extract. Respiratory burst activity was observed to be the highest in the 0.5 g kg -1 black cumin extract fed group. Lysozyme and myeloperoxidase activities were significantly increased in fish of experimental groups compared to control (P  0.05) after challenged with Aeromonas hydrophila. The results indicate that the methanolic extract of black cumin is a stimulator of some innate humoral immune responses, but it is ineffective for cytokine-related gene trancriptions in rainbow trout. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. Behaviour of rainbow trout ( Oncorhynchus mykiss) under defensible and indefensible patterns of food delivery

    Science.gov (United States)

    Saeed Heydarnejad, M.; Purser, G. J.

    2010-07-01

    The goal of this study was to investigate the behaviour of rainbow trout ( n=30), Oncorhynchus mykiss, in small raceways when either self-feeders (T2) or hand-feeding (t2) were used. The method of food delivery in T2 was defensible while that of t2 was indefensible. Fish in both raceways were subjected to restricted feeding (RF) for 25 days. Food was available in the morning (09:00-10:00) in the downstream area and in the afternoon (16:00-17:00) in the upstream area of the raceways. The results showed that the behaviour of rainbow trout was significantly different under interference competition (T2) for food compared with that under scramble competition (t2). RF in T2 fish limited food availability to meal times when feeding rewards were available while t2 fish only responded to the location of food delivery. The aggressive fish in T2 were dominant, and t2 fish at high densities showed intense social interactions under the indefensible pattern of food distribution; these interactions did not dampen to a minimum level to suppress the development of dominance hierarchies. Further, the stocking density did not break down the dominance hierarchies between the T2 fish. This suggests that decreased efficiency in the search for food or inefficient foraging, induced by interference competition at high densities, affected the behaviour of rainbow trout.

  18. Subunit vaccine candidates against Aeromonas salmonicida in rainbow trout Oncorhynchus mykiss.

    Science.gov (United States)

    Marana, Moonika Haahr; Jørgensen, Louise von Gersdorff; Skov, Jakob; Chettri, Jiwan Kumar; Holm Mattsson, Andreas; Dalsgaard, Inger; Kania, Per Walter; Buchmann, Kurt

    2017-01-01

    Aeromonas salmonicida subsp. salmonicida is the etiological agent of furunculosis and a major fish health problem in salmonid aquaculture worldwide. Injection vaccination with commercial mineral oil-adjuvanted bacterin vaccines has been partly successful in preventing the disease but in Danish rainbow trout (Oncorhynchus mykiss, Walbaum) aquaculture furunculosis outbreaks still occur. In this study we tested the efficacy of experimental subunit vaccines against A. salmonicida infection in rainbow trout. We utilized in silico screening of the proteome of A. salmonicida subsp. salmonicida strain A449 and identified potential protective protein antigens that were tested by in vivo challenge trial. A total of 14 proteins were recombinantly expressed in Escherichia coli and prepared in 3 different subunit vaccine combinations to immunize 3 groups of rainbow trout by intraperitoneal (i.p.) injection. The fish were exposed to virulent A. salmonicida 7 weeks after immunization. To assess the efficacy of the subunit vaccines we evaluated the immune response in fish after immunization and challenge infection by measuring the antibody levels and monitoring the survival of fish in different groups. The survival of fish at 3 weeks after challenge infection showed that all 3 groups of fish immunized with 3 different protein combinations exhibited significantly lower mortalities (17-30%) compared to the control groups (48% and 56%). The ELISA results revealed significantly elevated antibody levels in fish against several protein antigens, which in some cases were positively correlated to the survival.

  19. Intracerebroventricular ghrelin treatment affects lipid metabolism in liver of rainbow trout (Oncorhynchus mykiss).

    Science.gov (United States)

    Velasco, Cristina; Librán-Pérez, Marta; Otero-Rodiño, Cristina; López-Patiño, Marcos A; Míguez, Jesús M; Soengas, José L

    2016-03-01

    We aimed to elucidate in rainbow trout (Oncorhynchus mykiss) the effects of central ghrelin (GHRL) treatment on the regulation of liver lipid metabolism, and the possible modulatory effect of central GHRL treatment on the simultaneous effects of raised levels of oleate. Thus, we injected intracerebroventricularly (ICV) rainbow trout GHRL in the presence or absence of oleate and evaluated in liver variables related to lipid metabolism. Oleate treatment elicited in liver of rainbow trout decreased lipogenesis and increased oxidative capacity in agreement with previous studies. Moreover, as demonstrated for the first time in fish in the present study, GHRL also acts centrally modulating lipid metabolism in liver, resulting in increased potential for lipogenesis and decreased potential for fatty acid oxidation, i.e. the converse effects to those elicited by central oleate treatment. The simultaneous treatment of GHRL and oleate confirmed these counteractive effects. Thus, the nutrient sensing mechanisms present in hypothalamus, particularly those involved in sensing of fatty acid, are involved in the control of liver energy metabolism in fish, and this control is modulated by the central action of GHRL. These results give support to the notion of hypothalamus as an integrative place for the regulation of peripheral energy metabolism in fish. Copyright © 2016 Elsevier Inc. All rights reserved.

  20. Puffy skin disease (PSD) in rainbow trout, Oncorhynchus mykiss (Walbaum): a case definition.

    Science.gov (United States)

    Maddocks, C E; Nolan, E T; Feist, S W; Crumlish, M; Richards, R H; Williams, C F

    2015-07-01

    Puffy skin disease (PSD) is a disease that causes skin pathology in rainbow trout, Oncorhynchus mykiss (Walbaum). Incidence of PSD in UK fish farms and fisheries has increased sharply in the last decade, with growing concern from both industry sectors. This paper provides the first comprehensive case definition of PSD, combining clinical and pathological observations of diseased rainbow trout from both fish farms and fisheries. The defining features of PSD, as summarized in the case definition, were focal lateral flank skin lesions that appeared as cutaneous swelling with pigment loss and petechiae. These were associated with lethargy, poor body condition, inappetance and low level mortality. Epidermal hyperplasia and spongiosis, oedema of the dermis stratum spongiosum and a mild diffuse inflammatory cellularity were typical in histopathology of skin. A specific pathogen or aetiology was not identified. Prevalence and severity of skin lesions was greatest during late summer and autumn, with the highest prevalence being 95%. Atypical lesions seen in winter and spring were suggestive of clinical resolution. PSD holds important implications for both trout aquaculture and still water trout fisheries. This case definition will aid future diagnosis, help avoid confusion with other skin conditions and promote prompt and consistent reporting. © 2014 John Wiley & Sons Ltd.

  1. Determination of astaxanthin concentration in Rainbow trout (Oncorhynchus mykiss) by multispectral image analysis

    DEFF Research Database (Denmark)

    Frosch, Stina; Dissing, Bjørn Skovlund; Ersbøll, Bjarne Kjær

    Astaxanthin is the single most expensive constituent in salmonide fish feed. Therefore control and optimization of the astaxanthin concentration from feed to fish is of paramount importance for a cost effective salmonide production. Traditionally, methods for astaxanthin determination include...... extraction of astaxanthin from the minced sample into a suitable solvent such as acetone or hexane before further analysis. The existing methods have several drawbacks including being destructive and labour consuming. Current state-of-the art vision systems for quality and process control in the fish...... to a larger degree than in a trichromatic image. In this study multispectral imaging has been evaluated for characterization of the concentration of astaxanthin in rainbow trout fillets. Rainbow trout’s (Oncorhynchus mykiss), were filleted and imaged using a rapid multispectral imaging device...

  2. Abnormal swimming behavior and increased deformities in rainbow trout Oncorhynchus mykiss cultured in low exchange water recirculation aquaculture systems

    Science.gov (United States)

    Two studies were conducted to determine if accumulating water quality parameters would negatively impact rainbow trout Oncorhynchus mykiss health and welfare within water recirculation aquaculture systems (WRAS) that were operated at low and near-zero water exchange, with and without ozonation, and ...

  3. Aqualase, a yeast-based in-feed probiotic, modulates intestinal microbiota, immunity and growth of rainbow trout Oncorhynchus mykiss

    DEFF Research Database (Denmark)

    Adel, Milad; Lazado, Carlo Cabacang; Safari, Reza

    2017-01-01

    Yeast probiotics have great promise, yet they received little attention in fish. This study investigated the influence of Aqualase, a yeast-based commercial probiotic composed of Saccharomyces cerevisiae and Saccharomyces elipsoedas, on health and performance of rainbow trout (Oncorhynchus mykiss...

  4. Granulomatous enteritis in rainbow trout (Oncorhynchus mykiss) associated with soya bean meal regardless of water dissolved oxygen level

    NARCIS (Netherlands)

    Mosberian-Tanha, P.; Landsverk, T.; Press, C.M.; Mydland, L.T.; Schrama, J.W.; Øverland, M.

    2018-01-01

    This study investigated morphological changes associated with soya bean meal-induced enteritis (SBMIE) in distal intestine (DI) of rainbow trout (Oncorhynchus mykiss) fed a soya bean meal (SBM)-based diet and exposed to normoxia or hypoxia created by optimal and low water flow rates, respectively. A

  5. Parental stress-coping styles affect the behaviour of rainbow trout Oncorhynchus mykiss at early developmental stages

    DEFF Research Database (Denmark)

    Höglund, Erik; Gjoen, H.-M.; Pottinger, T.G.

    2008-01-01

    This work examined behavioural responses in yolk-sac rainbow trout Oncorhynchus mykiss larvae originating from strains selected for high (HR) or low (LR) plasma cortisol response to a standardized stressor. The results showed that yolk-sac larvae originating from the HR strain were more sensitive...

  6. Habitat-specific biomass, survival and growth of rainbow trout (Oncorhynchus mykiss) during summer in a small coastal stream

    Science.gov (United States)

    Bret C. Harvey; Jason L. White; Rodney J. Nakamoto

    2005-01-01

    We observed significant habitat-scale variation in the density, survival, and growth of 811 passive integrated transponder tagged rainbow trout (Oncorhynchus mykiss) enclosed for 63—68 days at natural density in 59 individual habitats (pools and riffles) in a small coastal California stream in summer 2001. The initial habitat-scale...

  7. Organic vegetable proteins and oil in feed for organic rainbow trout (Oncorhynchus mykiss)

    DEFF Research Database (Denmark)

    Lund, Ivar; Dalsgaard, Anne Johanne Tang; Jokumsen, Alfred

    The demand for organic trout is increasing, stressing the need for organic, vegetable feed ingredients as replacement for fish meal, as the principles of organic aquaculture encourage the development of feed that do not deplete global fish stocks. In addition, the organic code of practice does...... not allow addition of artificial amino acids to the feed, and optimization of the amino acid profile of organically based diets must therefore derive from the protein sources alone. The aim of this study was to evaluate the digestibility and growth performance of organic vegetable dietary ingredients...... as replacement for fish meal and fish oil in feed for organic rainbow trout (Oncorhynchus mykiss). Six iso-energetic and iso- nitrogenous diets were prepared, comprising a fish meal and fish oil based control diet and three diets in which the inclusion of fish meal was gradually reduced from 59 to 35...

  8. Microsomal biotransformation of chlorpyrifos, parathion and fenthion in rainbow trout (Oncorhynchus mykiss) and coho salmon (Oncorhynchus kisutch): mechanistic insights into interspecific differences in toxicity

    Science.gov (United States)

    Lavado, Ramon

    2010-01-01

    Rainbow trout often serve as a surrogate species evaluating xenobiotic toxicity in cold-water species including other salmonids of the same genus, which are listed as threatened or endangered. Biotransformation tends to show species-specific patterns that influence susceptibility to xenobiotic toxicity, particularly organophoshpate insecticides (OPs). To evaluate the contribution of biotransformation in the mechanism of toxicity of three organophosphate (phosphorothionate) insecticides, chlorpyrifos, parathion and fenthion, microsomal bioactivation and detoxification pathways were measured in gills, liver and olfactory tissues in juvenile rainbow trout (Oncorhynchus mykiss) and compared to juvenile coho salmon (Oncorhynchus kisutch). Consistent with species differences in acute toxicity, significantly higher chlorpyrifos bioactivation was found in liver microsomes of rainbow trout (up to 2-fold) when compared with coho salmon. Although bioactivation to the oxon was observed, the catalytic efficiency towards chlorpyrifos dearylation (detoxification) was significantly higher in liver for both species (1.82 and 0.79 for trout and salmon, respectively) when compared to desulfuration (bioactivation). Bioactivation of parathion to paraoxon was significantly higher (up to 2.2-fold) than detoxification to p-nitrophenol in all tissues of both species with rates of conversion in rainbow trout, again significantly higher than coho salmon. Production of fenoxon and fenthion sulfoxides from fenthion was detected only in liver and gills of both species with activities in rainbow trout significantly higher than coho salmon. NADPH-Dependent hydrolysis of fenthion was observed in all tissues, and was the only activity detected in olfactory tissues. These results indicate rainbow trout are more sensitive than coho salmon to the acute toxicity of OP pesticides because trout have higher catalytic rates of oxon formation. Thus, rainbow trout may serve as a conservative surrogate

  9. Effect of vitamin C on innate immune responses of rainbow trout (Oncorhynchus mykiss) leukocytes.

    Science.gov (United States)

    Leal, Esther; Zarza, Carlos; Tafalla, Carolina

    2017-08-01

    Vitamin C, also known as ascorbic acid, is an essential micronutrient that influences a wide variety of physiological processes, including immunological functions. Although the positive effects of vitamin C supplementation on the immunological status of fish has been established in different species, the bases for these positive effects are still unknown. Hence, the aim of our study was to evaluate the in vitro effect of vitamin C on several innate immune functions of rainbow trout (Oncorhynchus mykiss) leukocyte populations. For this, we assessed the effects exerted on the established rainbow trout monocyte-macrophage cell line RTS11, and compared them to those observed in trout head kidney leukocytes. Our results demonstrate that vitamin C increases the production of reactive oxygen species and the percentage of phagocytic cells in both cell populations. On the other hand, vitamin C had no effect on the surface MHC II levels and only in the case of RTS11 cells increased the capacity of these cells to migrate towards the CK9 chemokine. Finally, vitamin C also increased the transcription of several pro-inflammatory and antimicrobial genes elicited by Escherichia coli, with some differences depending on the cell population studied. Our results contribute to further understand how vitamin C supplementation regulates the fish immune system. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. Hexamitiasis leads to lower metabolic rates in rainbow trout Oncorhynchus mykiss (Walbaum) juveniles.

    Science.gov (United States)

    Ogut, H; Parlak, R

    2014-12-01

    This study assessed the effects of Hexamita salmonis (Moore) on metabolism of rainbow trout Oncorhynchus mykiss (Walbaum) and its effect on the host's susceptibility to infectious pancreatic necrosis virus (IPNV) after antiparasitic treatment. Rainbow trout naturally infected with H. salmonis were treated with 10 mg metronidazole kg fish(-1) per day, and their physiological recovery was assessed through measuring resting metabolism on the 7th, 14th, 21st and 28th day after treatment. In addition, we exposed the naïve fish to H. salmonis and measured the resting metabolism (oxygen consumption as mg O2 kg(-1) per hour) on the 10th, 20th and 30th day after the exposure to assess the variation in metabolic rates after infection. Significantly lower rates of metabolic activity (P trout to IPNV remained unchanged in the presence of H. salmonis. Weight loss was significantly higher (P < 0.05) in infected than that in the parasite-free fish. Fish should be examined regularly for H. salmonis and treated immediately whether found to prevent economic losses and excessive size variation. © 2013 John Wiley & Sons Ltd.

  11. Assessment of ranges plasma indices in rainbow trout (Oncorhynchus mykiss reared under conditions of intensive aquaculture

    Directory of Open Access Journals (Sweden)

    Radovan Kopp

    2011-01-01

    Full Text Available Plasma parameters in rainbow trout (Oncorhynchus mykiss from three various trout farms in the Czech Republic were assessed using automated blood plasma analyser. Non-haemolysed serum from the heart of 48 healthy, randomly selected fish (standard length, mean ± SD = 247.3 ± 24.2 mm; body mass, mean ± SD = 262.18 ± 87.28 g was analysed for the following plasma parameters: alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, acid phosphatase, lactate dehydrogenase, creatine kinase, total protein, cholinesterase, amylase, glucose, lactate, albumin, urea, cholesterol, triglycerides, lipase, Ca, Mg, P, Fe, Na, K and Cl. All data were analysed statistically such as normality assessment by means of Kolmogorov–Smirnov test and adequate statistical testing using various parametric and non-parametric tests for each variable. With regard to data distribution, 19 indices out of 23 (aspartate aminotransferase, alkaline phosphatase, acid phosphatase, lactate dehydrogenase, total protein, amylase, glucose, lactate, albumin, urea, cholesterol, triglycerides, Ca, Mg, P, Fe, Na, K and Cl were normally distributed. The indices were affected by handling time and, accordingly to the physical and chemical properties of water. Estimates obtained were compared with previously reported ranges. The blood automated analyser proved to be a valuable and reliable instrument for the estimation of plasma parameters determining normal ranges in rainbow trout.

  12. Ionoregulatory disruption as the acute toxic mechanism for lead in the rainbow trout (Oncorhynchus mykiss)

    International Nuclear Information System (INIS)

    Rogers, J.T.; Richards, J.G.; Wood, C.M.

    2003-01-01

    The mechanism for acute toxicity of lead (Pb) in rainbow trout (Oncorhynchus mykiss) was investigated at Pb concentrations close to the 96 h LC50 of 1.0 mg dissolved Pb l -1 (0.8-1.4, 95% C.I.) determined in dechlorinated Hamilton city tap water (from Lake Ontario, hardness=140 mg l -1 CaCO 3 ). Tissue Pb accumulation associated with death was highest in the gill, followed by kidney and liver. Significant ionoregulatory impacts were observed in adult rainbow trout (200-300 g) fitted with indwelling dorsal aortic catheters and exposed to 1.1±0.04 mg dissolved Pb l -1 . Decreased plasma [Ca 2+ ], [Na + ] and [Cl - ] occurred after 48 h of exposure through to 120 h, with increases in plasma [Mg 2+ ], ammonia, and cortisol. No marked changes in PaO 2 , PaCO 2 , pH, glucose, or hematological parameters were evident. Branchial Na + /K + ATPase activity in juvenile trout exposed to concentrations close to the 96 h LC50 was inhibited by approximately 40% after 48 h of Pb exposure. Calcium ion flux measurements using 45 Ca as a radiotracer showed 65% inhibition of Ca 2+ influx after 0, 12, 24 or 48 h exposure to the 96 h LC50 concentration of Pb. There was also significant inhibition (40-50%) of both Na + and Cl - uptake, measured with 22 Na and 36 Cl simultaneously. We conclude that the mechanism of acute toxicity for Pb in rainbow trout occurs by ionoregulatory disruption rather than respiratory or acid/base distress at Pb concentrations close to the 96 h LC50 in moderately hard water

  13. The effects of exogenous cortisol on myostatin transcription in rainbow trout, Oncorhynchus mykiss.

    Science.gov (United States)

    Galt, Nicholas J; Froehlich, Jacob Michael; Remily, Ethan A; Romero, Sinibaldo R; Biga, Peggy R

    2014-09-01

    Glucocorticoids (GCs) strongly regulate myostatin expression in mammals via glucocorticoid response elements (GREs), and bioinformatics methods suggest that this regulatory mechanism is conserved among many vertebrates. However, the multiple myostatin genes found in some fishes may be an exception. In silico promoter analyses of the three putative rainbow trout (Oncorhynchus mykiss) myostatin promoters have failed to identify putative GREs, suggesting a divergence in myostatin function. Therefore, we hypothesized that myostatin mRNA expression is not regulated by glucocorticoids in rainbow trout. In this study, both juvenile rainbow trout and primary trout myoblasts were treated with cortisol to examine the effects on myostatin mRNA expression. Results suggest that exogenous cortisol does not regulate myostatin-1a and -1b expression in vivo, as myostatin mRNA levels were not significantly affected by cortisol treatment in either red or white muscle tissue. In red muscle, myostatin-2a levels were significantly elevated in the cortisol treatment group relative to the control, but not the vehicle control, at both 12 h and 24 h post-injection. As such, it is unclear if cortisol was acting alone or in combination with the vehicle. Cortisol increased myostatin-1b expression in a dose-dependent manner in vitro. Further work is needed to determine if this response is the direct result of cortisol acting on the myostatin-1b promoter or through an alternative mechanism. These results suggest that regulation of myostatin by cortisol may not be as highly conserved as previously thought and support previous work that describes potential functional divergence of the multiple myostatin genes in fishes. Copyright © 2014 Elsevier Inc. All rights reserved.

  14. Ionoregulatory disruption as the acute toxic mechanism for lead in the rainbow trout (Oncorhynchus mykiss)

    Energy Technology Data Exchange (ETDEWEB)

    Rogers, J.T.; Richards, J.G.; Wood, C.M

    2003-07-16

    The mechanism for acute toxicity of lead (Pb) in rainbow trout (Oncorhynchus mykiss) was investigated at Pb concentrations close to the 96 h LC50 of 1.0 mg dissolved Pb l{sup -1} (0.8-1.4, 95% C.I.) determined in dechlorinated Hamilton city tap water (from Lake Ontario, hardness=140 mg l{sup -1} CaCO{sub 3}). Tissue Pb accumulation associated with death was highest in the gill, followed by kidney and liver. Significant ionoregulatory impacts were observed in adult rainbow trout (200-300 g) fitted with indwelling dorsal aortic catheters and exposed to 1.1{+-}0.04 mg dissolved Pb l{sup -1}. Decreased plasma [Ca{sup 2+}], [Na{sup +}] and [Cl{sup -}] occurred after 48 h of exposure through to 120 h, with increases in plasma [Mg{sup 2+}], ammonia, and cortisol. No marked changes in PaO{sub 2}, PaCO{sub 2}, pH, glucose, or hematological parameters were evident. Branchial Na{sup +}/K{sup +} ATPase activity in juvenile trout exposed to concentrations close to the 96 h LC50 was inhibited by approximately 40% after 48 h of Pb exposure. Calcium ion flux measurements using {sup 45}Ca as a radiotracer showed 65% inhibition of Ca{sup 2+} influx after 0, 12, 24 or 48 h exposure to the 96 h LC50 concentration of Pb. There was also significant inhibition (40-50%) of both Na{sup +} and Cl{sup -} uptake, measured with {sup 22}Na and {sup 36}Cl simultaneously. We conclude that the mechanism of acute toxicity for Pb in rainbow trout occurs by ionoregulatory disruption rather than respiratory or acid/base distress at Pb concentrations close to the 96 h LC50 in moderately hard water.

  15. Chromosome rearrangements, recombination suppression, and limited segregation distortion in hybrids between Yellowstone cutthroat trout (Oncorhynchus clarkii bouvieri) and rainbow trout (O. mykiss)

    Science.gov (United States)

    2013-01-01

    Background Introgressive hybridization is an important evolutionary process that can lead to the creation of novel genome structures and thus potentially new genetic variation for selection to act upon. On the other hand, hybridization with introduced species can threaten native species, such as cutthroat trout (Oncorhynchus clarkii) following the introduction of rainbow trout (O. mykiss). Neither the evolutionary consequences nor conservation implications of rainbow trout introgression in cutthroat trout is well understood. Therefore, we generated a genetic linkage map for rainbow-Yellowstone cutthroat trout (O. clarkii bouvieri) hybrids to evaluate genome processes that may help explain how introgression affects hybrid genome evolution. Results The hybrid map closely aligned with the rainbow trout map (a cutthroat trout map does not exist), sharing all but one linkage group. This linkage group (RYHyb20) represented a fusion between an acrocentric (Omy28) and a metacentric chromosome (Omy20) in rainbow trout. Additional mapping in Yellowstone cutthroat trout indicated the two rainbow trout homologues were fused in the Yellowstone genome. Variation in the number of hybrid linkage groups (28 or 29) likely depended on a Robertsonian rearrangement polymorphism within the rainbow trout stock. Comparison between the female-merged F1 map and a female consensus rainbow trout map revealed that introgression suppressed recombination across large genomic regions in 5 hybrid linkage groups. Two of these linkage groups (RYHyb20 and RYHyb25_29) contained confirmed chromosome rearrangements between rainbow and Yellowstone cutthroat trout indicating that rearrangements may suppress recombination. The frequency of allelic and genotypic segregation distortion varied among parents and families, suggesting few incompatibilities exist between rainbow and Yellowstone cutthroat trout genomes. Conclusions Chromosome rearrangements suppressed recombination in the hybrids. This result

  16. Expression of microRNAs and interferon-related genes in rainbow trout (Oncorhynchus mykiss Walbaum) infected with Viral hemorrhagic septicemia virus

    DEFF Research Database (Denmark)

    Bela-Ong, Dennis; Schyth, Brian Dall; Lorenzen, Niels

    The fish rhabdovirus Viral hemorrhagic septicemia virus (VHSV) causes severe disease in farmed rainbow trout (Oncorhynchus mykiss). The potential threat from wildlife marine reservoir of VHSV, particularly to sea-farmed fish demands disease protection measures. Identification of biomarkers during...

  17. Effects of 2-phenoxyethanol Anaesthesia on Haematological Profile on Common Carp (Cyprinus carpio and Rainbow Trout (Oncorhynchus mykiss

    Directory of Open Access Journals (Sweden)

    J. Velíšek

    2007-01-01

    Full Text Available The aim of this study was to assess changes in haematological profile of common carp (Cyprinus carpio and rainbow trout (Oncorhynchus mykiss after the exposure to anaesthetic 2-phenoxyethanol. The haematological profile was assessed before, immediately after 10 min of anaesthesia and 24 h after the anaesthesia with recommended concentration of 0.30 ml l-1 2-phenoxyethanol. The 10-min exposure to 2-phenoxyethanol of common carp caused the significant increase (p -1 does not cause irreversible damage of the blood in common carp and rainbow trout.

  18. The introduction of rainbow trout (Oncorhynchus mykiss in the context of socio-spatial Serra Catarinense.

    Directory of Open Access Journals (Sweden)

    Felipe Luiz

    2015-11-01

    Full Text Available This article aims to rescue the historical data of the introduction of rainbow trout in the socio-spatial context of the Sierra Santa Catarina, particularly URUBICI / SC municipality. Despite being a kind associated with economic benefits, the process of introduction of trout Oncorhynchus mykiss often has brought environmental and socioeconomic damage whose effects are still unknown. Trout was introduced in Brazil for the first time in 1949 in the Serra da Bocaina (MG and Southeast. The main reasons for its introduction in Brazilian rivers have been the increase in and Rio Macae (RJ in 1952. Currently, the species can now be found in all the states of the South sport fishing and tourism, often on the grounds of alleged lack of other species of fish in the rivers, as happened for example in Sierra Santa Catarina. More recently the Law nº1098 by prohibiting the creation of exotic species in Brazilian rivers included the trout which was later also excluded from this relationship that allowed the creation of this kind continue to occur. Although historically trout has been introduced by government initiative, and the legislation has been lenient, the main supporters of this activity, now are businessmen in the tourist industry and anglers. The trout farming has also been practiced for sale of live specimens, without obtaining the environmental license. Restrictive environmental standards are very recent and little publicized. Impact assessment studies on the native fauna to support educational campaigns and to propose measures for handling and marketing Trout are recommended actions.

  19. Cell-mediated cytotoxicity in rainbow trout, Oncorhynchus mykiss, infected with viral haemorrhagic septicaemia virus

    DEFF Research Database (Denmark)

    Utke, K.; Bergmann, S.; Lorenzen, Niels

    2007-01-01

    classical MHC class I locus Onmy-UBA is identical in the rainbow trout clone C25 and in the permanent rainbow trout cell line RTG-2. This enabled us to develop an assay to measure antiviral cytotoxicity in rainbow trout using a system of MHC class I-matched effector and target cells. Peripheral blood...... leucocytes (PBL) isolated from low dose viral haemorrhagic septicaemia virus (VHSV)-infected rainbow trout killed MHC class I-matched and later also xenogeneic MHC class I-mismatched VHSV-infected cells. When compared to PBL from uninfected control fish PBL from infected fish showed a higher transcriptional...

  20. Simulating Spawning and Juvenile Rainbow Trout (Oncorhynchus mykiss Habitat in Colorado River Based on High-Flow Effects

    Directory of Open Access Journals (Sweden)

    Weiwei Yao

    2017-02-01

    Full Text Available High flow generates significant alterations in downstream river reaches, resulting in physical condition changes in the downstream regions of the river such as water depth, flow velocity, water temperature and river bed. These alterations will lead to change in fish habitat configuration in the river. This paper proposes a model system to evaluate the high flow effects on river velocity, water depth, substrates changes, temperature distribution and consequently assess the change in spawning and juvenile rainbow trout (Oncorhynchus mykiss habitats in the downstream region of the Glen Canyon Dam. Firstly, based on the 2 dimensional (2D depth-averaged CFD (Computational Fluid Dynamics model and heat transfer equation applied for simulation, three indices were simulated, namely depth, flow velocity and temperature distribution. Then, the spawning and juvenile fish preference curves were obtained based on these three indices and substrates distribution. After that, the habitat model was proposed and used to simulate the high flow effects on juvenile and spawning rainbow trout habitat structure. Finally, the weighted usable area (WUA and overall suitability index (OSI of the spawning and juvenile fish species were quantitatively simulated to estimate the habitat sensitivity. The results illustrate that the high flow effect (HFE increased the juvenile rainbow trout habitat quality but decreased the spawning rainbow trout habitat quality. The juvenile trout were mainly affected by the water depth while the spawning rainbow trout were dominated by the bed elevation.

  1. Embryotoxicity of quantum dots in rainbow trout Oncorhynchus mykiss during hatching period

    Directory of Open Access Journals (Sweden)

    Nijolė Kazlauskienė

    2015-11-01

    Full Text Available Research on quantum dots (QD has become a major interdisciplinary area of science. Unique physic-chemical properties of QD significantly expanded areas of their application and increased the potential impact on hydrosystems. The objectives of complex study (using toxicological, physical, chemical methods were: to determine the toxicity of QD to rainbow trout (Oncorhynchus mykiss during ontogenesis (embryos, larvae depending on the duration of exposure; to estimate QD stability; to investigate QD uptake routes, distribution, accumulation, localization in tissues and different organs of embryos and larvae. This study examined the toxic effects of CdSe/ZnS-COOH at sublethal concentration. Bioassay testing was carried out under controlled laboratory conditions. Short-term (24-, 96-hour and long-term toxicity tests (14-day on fish at early stages of development (starting from “eye-egg” embryos were performed under static conditions. Mortality, physiological parameters, blood circulatory system, development disorders, behavioural responses and growth parameters of larvae were investigated. The results indicated that toxic effects of QD to rainbow trout in early life stages of development depended on the duration of exposure. Long-term exposure of QD induced remarkable deleterious changes in various systems of the developing fish organism: increased mortality, alterations in cardio-respiratory system, disturbed behavioural responses, caused developmental disorders and adversely affected the growth of larvae. Using physical methods it was determined: QD stability, uptake routes, distribution, accumulation and localization in tissues as well as in different organs of embryos and larvae of rainbow trout. Fish toxicity tests results will help to understand ecotoxicity of nanoparticles and will be used as nanoparticle embryotoxicity model in humans and other organisms.

  2. Gills as morphological biomarkers in extensive and intensive rainbow trout (Oncorhynchus mykiss, Walbaum 1792) production technologies.

    Science.gov (United States)

    Strzyżewska-Worotyńska, Emilia; Szarek, Józef; Babińska, Izabella; Gulda, Dominika

    2017-11-06

    We investigated environmental impacts on rainbow trout (Oncorhynchus mykiss) reared at fish farms with either extensive technology, in a flow-through system (FTS, n = 3), or intensive technology, in a recirculating aquaculture system (RAS, n = 3). All fish were fed the same rations. Fish were caught in spring and autumn (body mass, 501-750 g) from these six farms. We performed macroscopic (intact fish) and microscopic (gills stained with haematoxylin/eosin) examinations. Lesions were categorised based on the type and location of structural abnormalities. The histopathological index (HAI) was calculated, and each lesion was scored. Fish reared in FTS or RAS were compared for the prevalence of morphological lesions. Gill epithelial hypertrophy and hyperplasia comprised 73% (RAS) to 79% (FTS) of all morphological abnormalities. In spring and autumn, lesions comprised, respectively, 11 and 18% (FTS) and 16 and 10% (RAS) mucous and chloride cell abnormalities and 8 and 4% (FTS) and 10 and 3% (RAS) blood vessel abnormalities. Diffuse, irreversible gill lesions were observed sporadically in all fish. Gill epithelium received the most exposure to environmental pathogens. HAIs indicated that normal gill architecture and minor lesions predominated in all fish. However, among trout caught in spring, moderate and extensive changes in gills occurred more commonly with RAS (34%) than with FTS (17%). Trout caught in autumn displayed no great differences. These results indicated that FTS prepared fish better than RAS for wintering. Moreover, we showed that gills were an excellent biomarker for analysing the impact of extensive and intensive production environments on rainbow trout.

  3. Evaluation of Yeast Biomass (Candida utilis in a Practical Diet for Rainbow Trout (Oncorhynchus mykiss

    Directory of Open Access Journals (Sweden)

    J.S. Goddard

    1999-01-01

    Full Text Available A yeast, Candida utilis, cultured on a substrate derived from a mixture of peat moss and fish processing waste, was substituted for fish meal in a practical diet for rainbow trout, Oncorhynchus mykiss. The formulated diets were isonitrogenous (40% crude protein and isoealoric (gross energy 20 kJ per g dry matter. During a 50-day feeding trial fish tripled in weight, and there were no significant differences in the mean final weights of groups of fish fed diets in which 0%, 25% and 35% of fishmeal had been replaced by yeast biomass. Diets containing yeast were palatable, as determined by food intake, and were highly digestible for protein. Carcass analysis revealed that the fish fed with yeast biomass had slightly higher crude protein and ash contents, and lower lipid levels than those of the control group. Significant reductions were recorded in food conversion efficiency as the yeast content of the diets increased. The results indicate the potential for partial replacement of fish meal (between 25-35% by Candida utilis biomass in feeds formulated for rainbow trout.

  4. Effect of hypoxia on specific dynamic action and postprandial cardiovascular physiology in rainbow trout (Oncorhynchus mykiss).

    Science.gov (United States)

    Eliason, Erika J; Farrell, Anthony P

    2014-05-01

    Fish routinely encounter hypoxic environments, which may have detrimental effects on digestion and performance. The present study measured oxygen consumption (MO2), gastrointestinal blood flow (GBF), cardiac output (Vb) and heart rate (f(H)) in rainbow trout Oncorhynchus mykiss at 10°C-11.5°C while exposed to a 1.5-h step-wise hypoxia treatment (80%, 60% and 40% saturation=16.7, 12.6 and 8.4 kPa, respectively), which began 4 h after being fed 1% of their body mass. GBF and f(H) significantly decreased by 41 and 25%-29%, respectively, at the most severe hypoxia step (40% saturation), while MO2 and Vb were maintained throughout the entire hypoxia exposure. Thus, GBF and f(H) were more sensitive to hypoxia than MO2 or Vb in digesting rainbow trout. Subsequent to the hypoxic exposure, the fish were returned to normoxia and monitored for a total of 50h after feeding. While the magnitude of SDA was unaffected, peak postprandial MO2 was reduced by 17%, and the duration of specific dynamic action (SDA) was prolonged by 6h in hypoxia-treated fish when compared to control fish. In conclusion, digestive performance was compromised both during and after the hypoxic exposure, which could lead to negative effects on growth. Copyright © 2014 Elsevier Inc. All rights reserved.

  5. Effects of Montreal municipal sewage effluents on immune responses of juvenile female rainbow trout (Oncorhynchus mykiss)

    International Nuclear Information System (INIS)

    Salo, Harri M.; Hebert, Nancy; Dautremepuits, Claire; Cejka, Patrick; Cyr, Daniel G.; Fournier, Michel

    2007-01-01

    The objective of this study was to examine the immunotoxicity of treated Montreal sewage effluents on juvenile female rainbow trout (Oncorhynchus mykiss). A comprehensive panel of immunological assays was used to evaluate the effects of exposure for 1 and 4 weeks to 1, 3, 10 and 20% sewage effluent. Phagocytic ingestion of fluorescent latex beads by head kidney macrophages and granulocytes was suppressed following 1-week of exposure, with the highest exposure concentration being the most suppressive. Phagocytic activity returned to control levels after 4 weeks of exposure. The cytotoxic activity of head kidney derived non-specific cytotoxic cells was enhanced after a 1-week exposure, especially at the lowest exposure concentration, and returned to control levels after 4 weeks of exposure. In vitro lymphocyte proliferation in response to LPS and ConA activation was not affected following sewage effluent exposure, but nonactivated, spontaneous proliferation of lymphocytes was suppressed in a dose-dependent manner after 4 weeks of exposure. Plasma lysozyme activity was elevated at lowest exposure concentration after 4 weeks. No changes were noted in either the blood leukocyte/erythrocyte ratio or in the proportion of circulating lymphocytes and thrombocytes. The proportion of circulating granulocytes increased following exposure for 4 weeks to the low effluent concentration. Plasma cortisol levels were not affected by effluent exposure suggesting that mechanisms other than stress influenced the observed immunomodulation. In summary, this study demonstrates that sewage effluent can alter the immune functions of rainbow trout

  6. Effect of ellagic acid on some haematological, immunological and antioxidant parameters of rainbow trout (Oncorhynchus mykiss).

    Science.gov (United States)

    Mişe Yonar, S; Yonar, M E; Yöntürk, Y; Pala, A

    2014-10-01

    In this study, effect of ellagic acid on some haematological, immunological and antioxidant parameters in the blood and various tissues of rainbow trout (Oncorhynchus mykiss) were examined. Four groups of rainbow trout were fed experimental diets containing either no ellagic acid (control) or supplemented with ellagic acid at 50 mg/kg diet (EA-50), 100 mg/kg diet (EA-100) or 150 mg/kg diet (EA-150) for 21 days. Samples of the blood and tissue (liver, kidney and spleen) were collected at the end of the experiment and analysed for their haematological profile (the red blood cell count, the haemoglobin concentration and the haematocrit level), immune response (the white blood cell count, the oxidative radical production (NBT activity), the total plasma protein and total immunoglobulin level) and oxidant/antioxidant status (the malondialdehyde level, the superoxide dismutase, catalase and glutathione peroxidase activity as well as the reduced glutathione concentration). The findings of this study demonstrated that ellagic acid had a positive effect on the haematological parameters, the immune response and the antioxidant enzyme activities of the fish. Journal of Animal Physiology and Animal Nutrition © 2014 Blackwell Verlag GmbH.

  7. Effects of Montreal municipal sewage effluents on immune responses of juvenile female rainbow trout (Oncorhynchus mykiss)

    Energy Technology Data Exchange (ETDEWEB)

    Salo, Harri M. [INRS-institut Armand-Frappier, 245 Hymus Boul., Pointe-Claire, Que. H9R 1G6 (Canada)], E-mail: harri.salo@ktl.fi; Hebert, Nancy; Dautremepuits, Claire [INRS-institut Armand-Frappier, 245 Hymus Boul., Pointe-Claire, Que. H9R 1G6 (Canada); Cejka, Patrick [Montreal Wastewater Treatment Plant, 12 001 Maurice-Duplessis, Montreal, Que. H1C 1V3 (Canada); Cyr, Daniel G.; Fournier, Michel [INRS-institut Armand-Frappier, 245 Hymus Boul., Pointe-Claire, Que. H9R 1G6 (Canada)

    2007-10-30

    The objective of this study was to examine the immunotoxicity of treated Montreal sewage effluents on juvenile female rainbow trout (Oncorhynchus mykiss). A comprehensive panel of immunological assays was used to evaluate the effects of exposure for 1 and 4 weeks to 1, 3, 10 and 20% sewage effluent. Phagocytic ingestion of fluorescent latex beads by head kidney macrophages and granulocytes was suppressed following 1-week of exposure, with the highest exposure concentration being the most suppressive. Phagocytic activity returned to control levels after 4 weeks of exposure. The cytotoxic activity of head kidney derived non-specific cytotoxic cells was enhanced after a 1-week exposure, especially at the lowest exposure concentration, and returned to control levels after 4 weeks of exposure. In vitro lymphocyte proliferation in response to LPS and ConA activation was not affected following sewage effluent exposure, but nonactivated, spontaneous proliferation of lymphocytes was suppressed in a dose-dependent manner after 4 weeks of exposure. Plasma lysozyme activity was elevated at lowest exposure concentration after 4 weeks. No changes were noted in either the blood leukocyte/erythrocyte ratio or in the proportion of circulating lymphocytes and thrombocytes. The proportion of circulating granulocytes increased following exposure for 4 weeks to the low effluent concentration. Plasma cortisol levels were not affected by effluent exposure suggesting that mechanisms other than stress influenced the observed immunomodulation. In summary, this study demonstrates that sewage effluent can alter the immune functions of rainbow trout.

  8. Experimental infection with epizootic haematopoietic necrosis virus (EHNV of rainbow trout (Oncorhynchus mykiss Walbaum and European perch (Perca fluviatilis L.

    Directory of Open Access Journals (Sweden)

    Borzym Ewa

    2015-12-01

    Full Text Available The aim of this study was the determination of the susceptibility of Polish farmed redfin perch (Perca fluviatilis L. and rainbow trout (Oncorhynchus mykiss Walbaum to experimental infection with haematopoietic necrosis virus (EHNV. A bath challenge model was tested at two temperature ranges: 13-15°C and 20-22°C. After 7 d, the first clinical signs and mortality were observed in fish kept at these temperatures. Significantly more mortality cases were reported in the redfin perch population, reaching a maximum of 24% compared with 12% in the rainbow trout group at 20-22°C. EHNV was reisolated from redfin perch and rainbow trout tissue in cell culture and the infection was confirmed by a molecular method and histopathology during the duration of the experiment. This study revealed that fish from Polish farms can be susceptible to EHNV even at lower temperatures.

  9. Identification of differentially expressed genes of brown trout (Salmo trutta) and rainbow trout (Oncorhynchus mykiss) in response to Tetracapsuloides bryosalmonae (Myxozoa).

    Science.gov (United States)

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

    2015-03-01

    Tetracapsuloides bryosalmonae Canning et al., 1999 (Myxozoa) is the causative agent of proliferative kidney disease in various species of salmonids in Europe and North America. We have shown previously that the development and distribution of the European strain of T. bryosalmonae differs in the kidney of brown trout (Salmo trutta) Linnaeus, 1758 and rainbow trout (Oncorhynchus mykiss) Walbaum, 1792, and that intra-luminal sporogonic stages were found in brown trout but not in rainbow trout. We have now compared transcriptomes from kidneys of brown trout and rainbow trout infected with T. bryosalmonae using suppressive subtractive hybridization (SSH). The differentially expressed transcripts produced by SSH were cloned, transformed, and tested by colony PCR. Differential expression screening of PCR products was validated using dot blot, and positive clones having different signal intensities were sequenced. Differential screening and a subsequent NCBI-BLAST analysis of expressed sequence tags revealed nine clones expressed differently between both fish species. These differentially expressed genes were validated by quantitative real-time PCR of kidney samples from both fish species at different time points of infection. Expression of anti-inflammatory (TSC22 domain family protein 3) and cell proliferation (Prothymin alpha) genes were upregulated significantly in brown trout but downregulated in rainbow trout. The expression of humoral immune response (immunoglobulin mu) and endocytic pathway (Ras-related protein Rab-11b) genes were significantly upregulated in rainbow trout but downregulated in brown trout. This study suggests that differential expression of host anti-inflammatory, humoral immune and endocytic pathway responses, cell proliferation, and cell growth processes do not inhibit the development of intra-luminal sporogonic stages of the European strain of T. bryosalmonae in brown trout but may suppress it in rainbow trout.

  10. Effects of maternal stress coping style on offspring characteristics in rainbow trout (Oncorhynchus mykiss)

    DEFF Research Database (Denmark)

    Åberg Andersson, Madelene; Silva, P.I.M.; Steffensen, J.F.

    2011-01-01

    Maternal size, age, and allostatic load influence offspring size, development, and survival. Some of these effects have been attributed to the release of glucocorticoids, and individual variation in these stress hormones is related to a number of traits. Correlated traits are often clustered...... and used to define the proactive and reactive stress coping styles. Although stress coping styles have been identified in a number of animal groups, little is known about the coupling between stress coping style and offspring characteristics. In the present study, plasma cortisol levels in ovulated mothers...... and cortisol levels in non-fertilized eggs from two rainbow trout (Oncorhynchus mykiss) strains selected for high (HR) and low (LR) post-stress plasma cortisol levels were compared. Offspring characteristics such as egg size, larval growth, and energy reserves also were compared between the two strains...

  11. Does feed composition affect oxidation of rainbow trout (Oncorhynchus mykiss) during frozen storage?

    DEFF Research Database (Denmark)

    Baron, Caroline; Hyldig, Grethe; Jacobsen, Charlotte

    2009-01-01

    that in this investigation fish fed fish oil were slightly more oxidized than fish fed vegetable oil. Results showed that canthaxanthin effectively protected both protein and lipid against oxidation during frozen storage. In contrast, astaxanthin did not seem to have a clear and systematic effect. Results indicated......Rainbow trout (Oncorhynchus mykiss) were fed a diet containing either fish oil or rapeseed oil and with or without 200 mg/kg carotenoid (either astaxanthin or canthaxanthin). A total of six diets were obtained: (1) fish oil/astaxanthin; (2) vegetable oil/astaxanthin; (3) fish oil/canthaxanthin; (4......) vegetable oil/canthaxanthin; (5) fish oil/no pigment; and (6) vegetable oil/no pigment. The fish were slaughtered and stored in polyethylene bags individually as butterfly fillets for up to 22 months at -20 C. The composition of the fish muscle at slaughter and during frozen storage was evaluated...

  12. Effects of plant proteins on postprandial, free plasma amino acid concentrations in rainbow trout (Oncorhynchus mykiss)

    DEFF Research Database (Denmark)

    Larsen, Bodil Katrine; Dalsgaard, Anne Johanne Tang; Pedersen, Per Bovbjerg

    2012-01-01

    proteins from wheat, peas, field beans, sunflower and soybean. Blood samples were obtained from the caudal vein of 7 fish in each dietary treatment group prior to feeding, as well as: 2, 4, 6, 8, 12, 24, 48 and 72 h after feeding (sampling 7 new fish at each time point), and plasma amino acid......Postprandial patterns in plasma free amino acid concentrations were investigated in juvenile rainbow trout (Oncorhynchus mykiss) fed either a fish meal based diet (FM) or a diet (VEG) where 59% of fish meal protein (corresponding to 46% of total dietary protein) was replaced by a matrix of plant...... the two dietary treatment groups correlated largely with the amino acid content of the two diets except for methionine, lysine and arginine, where the differences were more extreme than what would be expected from differences in dietary concentrations. The apparent protein digestibility coefficient...

  13. Variation in Sensory Profile of Individual Rainbow Trout (Oncorhynchus mykiss) from the Same Production Batch

    DEFF Research Database (Denmark)

    Green-Petersen, Ditte; Hyldig, Grethe

    2010-01-01

    The variation in sensory profile of rainbow trout (Oncorhynchus mykiss), belonging to the same aquaculture production batch and handled the same way, was explored by using objective sensory profiling on heat-treated minced fillets. In addition, quality index, mechanical texture, pH, fat, and water...... content were measured. Different groups of fish were sampled 3 different times during a production day. The results showed significant differences in the sensory profiles of individual fish within all 3 groups as well as significant differences between the groups. Differences in mechanical texture were...... not explain the differences in the sensory profiling or in the mechanical texture measurements. The results showed that significant differences in the sensory profiles of individual fish from the same aquaculture production batch may occur. Furthermore, the results also showed sensory differences between...

  14. Effects of Levamisole on Phagocytic Activity of Rainbow Trout (Oncorhynchus mykiss W.

    Directory of Open Access Journals (Sweden)

    U. Ispir

    2007-01-01

    Full Text Available In this study, activation of phagocytic cells was examined in rainbow trout (Oncorhynchus mykiss W. exposed to 1, 5 and 10 μg ml-1 concentrations of levamisole solution. For this purpose, blood samples were taken from fish on days 1, 7 and 14 of exposure. Potential killing activity was determined by measuring oxidative radical production and phagocytic activity of neutrophils and superoxide anion production of phagocytic cells against Y. ruckeri. The activity of phagocytic cells in fish exposed to each of three concentrations was found higher than that in controls and the differences were statistically significant (p p -1 concentration of levamisole solution was determined on day 7, it was observed that all indicators increased on day 14 of exposure. The present results suggest that the application of levamisole in fish farms could increase non-specific immunity and resistance to infection of fish and offer economics benefits.

  15. Blood ph and mortality of rainbow trout (Salmo gairdnerii) and sockeye salmon (Oncorhynchus nerka)

    Energy Technology Data Exchange (ETDEWEB)

    Jonas, R E.E.; Sehdev, H S; Tomlinson, N

    1972-01-01

    Rainbow trout (Salmo gairdnerii) under light anaesthesia with MS 222 (Tricaine methanesulphonate) died when their blood pH was lowered into the range of 6.8 to 6.9 by injection of either lactic acid or hydrochloric acid. When injection of the same quantities of either acid did not lower the blood pH into this range, fatalities did not result (one exception in 56 fish injected). The injection of much larger quantities of lactate of chloride ions in the form of sodium salts did not cause fatalities. Very limited date for sockeye salmon (Oncorhynchus nerka) suggest a similar association between blood pH and mortality for this species.

  16. Tetraploidy Determination in Rainbow Trout (Oncorhynchus mykiss Based on Erythrocytes Dimensions

    Directory of Open Access Journals (Sweden)

    Ioan Bencsik

    2012-05-01

    Full Text Available Tetraploidy induction at fish is characterized by modification of normal diploid chromosome set (2n into tetraploid set (4n. Experiments were carried out on biological material from rainbow trout (Oncorhynchus mikiss during the natural breeding season. Polyploidy was induced by exposing the eggs to heat shock. Blood smear was used as a technical method, to determine diploid and tetraploid status. Staining of blood smear was performed by Pappenhein method. The erythrocytes area and perimeter measurements done comparatively on tetraploid and diploid individuals may represent an indicator to determine the ploidy level of individuals. Erythrocytes area for tetraploid individuals is 2.18 times higher than at diploid individuals, and perimeter 1.45 times higher than in diploid individuals.

  17. Phenotypic and Genotypic Antimicrobial Resistance of Lactococcus Sp. Strains Isolated from Rainbow Trout (Oncorhynchus Mykiss

    Directory of Open Access Journals (Sweden)

    Ture Mustafa

    2015-04-01

    Full Text Available A current profile of antimicrobial resistance and plasmid of 29 Lactococcus garvieae and one Lactococcus lactis strains isolated from rainbow trouts (Oncorhynchus mykiss from farms throughout Turkey were investigated. All isolates were sensitive to penicillin G (90%, ampicillin (86.7%, florfenicol (83.3%, amoxicillin (80.1%, and tetracycline (73.4%, and resistant to trimethoprim+sulfamethoxazole (86.6% and gentamycin (46.6% by disc diffusion method. Twenty-eight (93% isolates had two to seven antibiotic resistance genes (ARGs determined by PCR. The most prevalent ARGs were tetracycline (tetB, erythromycin (ereB, and β-lactam (blaTEM. Bacterial strains were also screened for plasmid DNA by agarose gel electrophoresis and two strains harboured plasmids, with sizes ranging from 3 to 9 kb.

  18. Tritium uptake in rainbow trout (Oncorhynchus mykiss): HTO and OBT-spiked feed exposures simultaneously

    International Nuclear Information System (INIS)

    Kim, S.B.; Shultz, C.; Stuart, M.; Festarini, A.

    2015-01-01

    There is currently considerable interest in organically bound tritium (OBT) formation in edible fish. The major questions revolve around whether or not tritium can accumulate in fish after being released into aquatic environments. Since OBT formation rates in large, edible fish are poorly understood, rainbow trout (Oncorhynchus mykiss) studies, where fish were simultaneously exposed to tritiated water (HTO) and OBT-spiked feed over 130 days, were conducted to evaluate tritium uptake. The measured HTO activity concentrations in fish tissue confirmed that HTO in fish tissue equilibrates quickly with HTO in tank water. The data obtained also confirmed that OBT uptake is faster when fish are ingesting OBT-spiked feed compared to when fish are living in tritiated water (and consuming non-OBT-spiked feed). The difference between the two exposure types is such that the groups exposed to tritiated water and OBT-spiked feed simultaneously were showing the same uptake rates as OBT-spiked feed only exposures. Contrary to what was expected, the rate of OBT uptake (from OBT-spiked feed) seemed to be higher in slow growing fish compared to fast growing fish. Another observation from these studies was that OBT activity concentrations in all organs (viscera) had a tendency to be higher than OBT activity concentrations measured in fish flesh. - Highlights: • Edible size of rainbow trout (Oncorhynchus mykiss) were simultaneously exposed to tritiated water (HTO) and OBT-spiked feed over 130 days. • OBT uptake is faster when fish are ingesting OBT-spiked feed compared to when fish are living in tritiated water (and consuming non-OBT-spiked feed). • The rate of OBT uptake (from OBT-spiked feed) seemed to be higher in slow growing fish compared to fast growing fish

  19. A novel role for pigment genes in the stress response in rainbow trout (Oncorhynchus mykiss)

    KAUST Repository

    Khan, Uniza Wahid

    2016-07-04

    In many vertebrate species visible melanin-based pigmentation patterns correlate with high stress- and disease-resistance, but proximate mechanisms for this trait association remain enigmatic. Here we show that a missense mutation in a classical pigmentation gene, melanocyte stimulating hormone receptor (MC1R), is strongly associated with distinct differences in steroidogenic melanocortin 2 receptor (MC2R) mRNA expression between high- (HR) and low-responsive (LR) rainbow trout (Oncorhynchus mykiss). We also show experimentally that cortisol implants increase the expression of agouti signaling protein (ASIP) mRNA in skin, likely explaining the association between HR-traits and reduced skin melanin patterning. Molecular dynamics simulations predict that melanocortin 2 receptor accessory protein (MRAP), needed for MC2R function, binds differently to the two MC1R variants. Considering that mRNA for MC2R and the MC1R variants are present in head kidney cells, we hypothesized that MC2R activity is modulated in part by different binding affinities of the MC1R variants for MRAP. Experiments in mammalian cells confirmed that trout MRAP interacts with the two trout MC1R variants and MC2R, but failed to detect regulation of MC2R signaling, possibly due to high constitutive MC1R activity.

  20. Regulation of proliferation and differentiation of adipocyte precursor cells in rainbow trout (Oncorhynchus mykiss).

    Science.gov (United States)

    Bouraoui, L; Gutiérrez, J; Navarro, I

    2008-09-01

    Here, we describe optimal conditions for the culture of rainbow trout (Oncorhynchus mykiss) pre-adipocytes obtained from adipose tissue and their differentiation into mature adipocytes, in order to study the endocrine control of adipogenesis. Pre-adipocytes were isolated by collagenase digestion and cultured on laminin or 1% gelatin substrate. The expression of proliferating cell nuclear antigen was used as a marker of cell proliferation on various days of culture. Insulin growth factor-I stimulated cell proliferation especially on days 5 and 7 of culture. Tumor necrosis factor alpha (TNFalpha) slightly enhanced cell proliferation only at a low dose. We verified the differentiation of cells grown in specific medium into mature adipocytes by oil red O (ORO) staining. Quantification of ORO showed an increase in triglycerides throughout culture. Immunofluorescence staining of cells at day 11 revealed the expression of CCAAT/enhancer-binding protein and peroxisome proliferator-activator receptor gamma, suggesting that these transcriptional factors are involved in adipocyte differentiation in trout. We also examined the effect of TNFalpha on the differentiation of these adipocytes in primary culture. TNFalpha inhibited the differentiation of these cells, as indicated by a decrease in glycerol-3-phosphate dehydrogenase activity, an established marker of adipocyte differentiation. In conclusion, the culture system described here for trout pre-adipocytes is a powerful tool to study the endocrine regulation of adipogenesis in this species.

  1. Effects of cooking techniques on fatty acid and oxylipin content of farmed rainbow trout (Oncorhynchus mykiss)

    Science.gov (United States)

    Rainbow trout is an excellent source of long chain omega-3 polyunsaturated fatty acids (PUFA) which have beneficial health effects. We determined the fatty acid and oxylipin content of 2-year old rainbow trout fillets that were raw, baked, broiled, microwaved, or pan-fried in corn (CO), canola (CaO...

  2. Spinal deformities in triploid all-female rainbow trout ( Oncorhynchus mykiss )

    DEFF Research Database (Denmark)

    Madsen, Lone; Arnbjerg, J.; Dalsgaard, Inger

    2000-01-01

    A batch of experimental rainbow trout was found to have a high level of spinal deformities. An equal deformity level was found in fish from the same batch, but reared at the fish farm from where the fry originated, suggesting that the all-female triploid status of the rainbow trout might account...

  3. Functional Identification of Dendritic Cells in the Teleost Model, Rainbow Trout (Oncorhynchus mykiss)

    Science.gov (United States)

    Bassity, Elizabeth; Clark, Theodore G.

    2012-01-01

    Dendritic cells are specialized antigen presenting cells that bridge innate and adaptive immunity in mammals. This link between the ancient innate immune system and the more evolutionarily recent adaptive immune system is of particular interest in fish, the oldest vertebrates to have both innate and adaptive immunity. It is unknown whether dendritic cells co-evolved with the adaptive response, or if the connection between innate and adaptive immunity relied on a fundamentally different cell type early in evolution. We approached this question using the teleost model organism, rainbow trout (Oncorhynchus mykiss), with the aim of identifying dendritic cells based on their ability to stimulate naïve T cells. Adapting mammalian protocols for the generation of dendritic cells, we established a method of culturing highly motile, non-adherent cells from trout hematopoietic tissue that had irregular membrane processes and expressed surface MHCII. When side-by-side mixed leukocyte reactions were performed, these cells stimulated greater proliferation than B cells or macrophages, demonstrating their specialized ability to present antigen and therefore their functional homology to mammalian dendritic cells. Trout dendritic cells were then further analyzed to determine if they exhibited other features of mammalian dendritic cells. Trout dendritic cells were found to have many of the hallmarks of mammalian DCs including tree-like morphology, the expression of dendritic cell markers, the ability to phagocytose small particles, activation by toll-like receptor-ligands, and the ability to migrate in vivo. As in mammals, trout dendritic cells could be isolated directly from the spleen, or larger numbers could be derived from hematopoietic tissue and peripheral blood mononuclear cells in vitro. PMID:22427987

  4. Does Oral Vaccination Protect Rainbow Trout (Oncorhynchus mykiss) Against Enteric Red Mouth Disease?

    DEFF Research Database (Denmark)

    Neumann, Lukas; Villumsen, Kasper Rømer; Kragelund Strøm, Helene

    . ruckeri bacteria are need in order to obtain significantly increased immunity against the disease. These results suggest that a high amount of the vaccine is digested in the stomach of the rainbow trout and therefore did not reach the intestine as immunogenic antigens. The project is still ongoing....... The objective for this project is to investigate whether oral vaccination of rainbow trout against Yersinia ruckeri O1 (biotype 1) causing Enteric Red Mouth disease (ERM) can protect rainbow trout against a subsequent experimental bath challenge with Y. ruckeri. The rainbow trout were given oral vaccinations...... primary vaccination), 5) AquaVac ERM (as a primary vaccine), 6) AquaVac w/ booster, and 7) one group with 10 fold increase (w/ booster) of the experimental vaccine in the feed. The rainbow trout were bath challenged with 6.3 x108 CFU/ml Y. ruckeri 6 month post the primary oral vaccination. The challenge...

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

    Science.gov (United States)

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

    2016-04-01

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

  6. Use of streambed substrate as refuge by steelhead or rainbow trout Oncorhynchus mykiss during simulated freshets.

    Science.gov (United States)

    Ligon, F K; Nakamoto, R J; Harvey, B C; Baker, P F

    2016-04-01

    A flume was used to estimate the carrying capacity of streambed substrates for juvenile steelhead or rainbow trout Oncorhynchus mykiss seeking refuge from simulated freshets. The simulated freshets had mean water column velocities of c. 1·1 m s(-1). The number of O. mykiss finding cover within the interstices of the substrate was documented for different substrate sizes and levels of embeddedness. The availability of suitable refuges determined the carrying capacity of the substrate for O. mykiss. For the size of the O. mykiss tested [mean ± s.d. fork length (L(F)) = 122 ± 12.6 mm], the number of interstices with depths ≥200 mm measured with a 14.0 mm diameter flexible plastic tube was the best predictor of the number of O. mykiss able to find cover (r(2)  = 0.75). Oncorhynchus mykiss seeking refuge from freshets may need deeper interstices than those seeking concealment at autumn or winter base flows. The availability of interstices suitable as refuge from high flows may determine autumn and winter carrying capacity. © 2016 The Fisheries Society of the British Isles.

  7. Compensatory growth response of rainbow trout Oncorhynchus mykiss Walbaum following short starvation periods

    Science.gov (United States)

    Azodi, Maryam; Ebrahimi, Eisa; Farhadian, Omidvar; Mahboobi-Soofiani, Nasrollah; Morshedi, Vahid

    2015-07-01

    This sixty-day study was performed to determine the effects of short-term starvation and re-feeding cycles on growth, feeding performances and body composition of rainbow trout ( Oncorhynchus mykiss). Three hundred trout fingerlings with an average initial weight of 17.5±0.06 g were randomly distributed in 15 circular fiberglass tanks. The fish were exposed to 5 different feeding regimes; control: continuously fed twice daily to apparent satiation; T1: starved for 1 day and re-fed for 2 days; T2: starved for 1 day and re-fed for 4 days; T3: starved for 3 days and re-fed for 12 days; T4: starved for 4 days and re-fed for 16 days. At the end of the experiment, growth performance, feed utilization, whole body ash and moisture contents were not significantly ( P>0.05) different among the treatments. However, whole body protein content in T3 was significantly higher than other treatments ( Ptrout culture.

  8. Kinetics of radiolabelled silver uptake and depuration in the gills of rainbow trout (Oncorhynchus mykiss) and European eel (Anguilla anguilla)

    DEFF Research Database (Denmark)

    Wood, C.M.; Grosell, M.; Hogstrand, C.

    2002-01-01

    We examined the influence of speciation on the kinetics of silver uptake and deputation in the gills of two freshwater fish, the rainbow trout (Oncorhynchus mykiss) which has high branchial Na+ and Cl- uptake rates and is relatively sensitive to silver, and the European eel (Anguilla anguilla...... labile than from Ag+ exposures, with 1.6-1.8-fold greater loss rates during the fast phases in both species. Differences in branchial silver uptake between eel and trout correlate well with differences in acute toxicity, but are not as large as differences in ion uptake rates. The complex time...

  9. Influence of dietary lipid and protein sources on the sensory quality of organic rainbow trout (Oncorhynchus mykiss) after ice storage

    DEFF Research Database (Denmark)

    Green-Petersen, Ditte; Hyldig, Grethe; Jacobsen, Charlotte

    2014-01-01

    The influence of dietary protein and lipid sources on the quality of organic rainbow trout (Oncorhynchus mykiss) was studied. The protein and oil sources were fishmeal, fish oil, and organic vegetable protein and oils. Sensory profiling was performed during 3 to 14 days of ice storage along...... with lipid analyses of the fillet. Overall, the results showed that the sensory characteristics of the trout were affected in different ways during ice storage. The source of lipid seemed to affect the sensory quality at the beginning of the storage period, while the protein source seemed to have a more...

  10. Effect of gamma radiation on the quality and shelf life of refrigerated rainbow trout (Oncorhynchus mykiss) fillets.

    Science.gov (United States)

    Moini, Sohrab; Tahergorabi, Reza; Hosseini, Seyed Vali; Rabbani, Mohammad; Tahergorabi, Zoya; Feás, Xesús; Aflaki, Fereidoon

    2009-07-01

    The effect of gamma radiation (0, 1, 3, and 5 kGy) on the shelf life of farmed rainbow trout (Oncorhynchus mykiss) fillets that were treated with sodium acetate and vacuum packaged and subsequently stored under refrigeration was studied by measuring microbiological, chemical, and organoleptic changes. Radiation affected populations of bacteria, namely, H2S-producing bacteria and Enterobacteriaceae (P biochemical indicators, thiobarbituric acid values for irradiated trout were higher than for nonirradiated fish (P biochemical indices of O. mykiss for up to 4 weeks at refrigerator temperature without adverse effects on quality and acceptability.

  11. Proteomic analysis of rainbow trout (Oncorhynchus mykiss) intestinal epithelia: physiological acclimation to short-term starvation.

    Science.gov (United States)

    Baumgarner, Bradley L; Bharadwaj, Anant S; Inerowicz, Dorota; Goodman, Angela S; Brown, Paul B

    2013-03-01

    The intestinal epithelia form the first line of defense against harmful agents in the gut lumen of most monogastric vertebrates, including teleost fishes. Previous investigations into the effect of starvation on the intestinal epithelia of teleost fishes have focused primarily on changes in morphological characteristics and targeted molecular analysis of specific enzymes. The goal of this study was to use a comprehensive approach to help reveal how the intestinal epithelia of carnivorous teleost fishes acclimate to short-term nutrient deprivation. We utilized two-dimensional gel electrophoresis (2-DE) to conduct the proteomic analysis of the mucosal and epithelial layer of the anterior gut intestinal tract (GIT) from satiation fed vs. 4 week starved rainbow trout (Oncorhynchus mykiss). A total of 40 proteins were determined to be differentially expressed and were subsequently picked for in-gel trypsin digestion. Peptide mass fingerprint analysis was conducted using matrix assisted laser desorption time-of-flight/time-of-flight. Nine of the 11 positively identified proteins were directly related to innate immunity. The expression of α-1 proteinase inhibitor decreased in starved vs. fed fish. Also, the concentration of one leukocyte elastase inhibitor (LEI) isomer decreased in starved fish, though the concentration of another LEI isomer increased in due to starvation. In addition, starvation promoted an increased concentration of the important xenobiotic-transporter p-glycoprotein. Finally, starvation resulted in a significant increase in type II keratin E2. Overall, our results indicate that starvation promoted a reduced capacity to inhibit enzymatic stress but increased xenobiotic resistance and paracellular permeability of epithelial cells in the anterior intestine of rainbow trout. Copyright © 2012 Elsevier Inc. All rights reserved.

  12. Exposure to seawater increases intestinal motility in euryhaline rainbow trout (Oncorhynchus mykiss).

    Science.gov (United States)

    Brijs, Jeroen; Hennig, Grant W; Gräns, Albin; Dekens, Esmée; Axelsson, Michael; Olsson, Catharina

    2017-07-01

    Upon exposure to seawater, euryhaline teleosts need to imbibe and desalinate seawater to allow for intestinal ion and water absorption, as this is essential for maintaining osmotic homeostasis. Despite the potential benefits of increased mixing and transport of imbibed water for increasing the efficiency of absorptive processes, the effect of water salinity on intestinal motility in teleosts remains unexplored. By qualitatively and quantitatively describing in vivo intestinal motility of euryhaline rainbow trout ( Oncorhynchus mykiss ), this study demonstrates that, in freshwater, the most common motility pattern consisted of clusters of rhythmic, posteriorly propagating contractions that lasted ∼1-2 min followed by a period of quiescence lasting ∼4-5 min. This pattern closely resembles mammalian migrating motor complexes (MMCs). Following a transition to seawater, imbibed seawater resulted in a significant distension of the intestine and the frequency of MMCs increased twofold to threefold with a concomitant reduction in the periods of quiescence. The increased frequency of MMCs was also accompanied by ripple-type contractions occurring every 12-60 s. These findings demonstrate that intestinal contractile activity of euryhaline teleosts is dramatically increased upon exposure to seawater, which is likely part of the overall response for maintaining osmotic homeostasis as increased drinking and mechanical perturbation of fluids is necessary to optimise intestinal ion and water absorption. Finally, the temporal response of intestinal motility in rainbow trout transitioning from freshwater to seawater coincides with previously documented physiological modifications associated with osmoregulation and may provide further insight into the underlying reasons shaping the migration patterns of salmonids. © 2017. Published by The Company of Biologists Ltd.

  13. The effect of vacuum packaging on physicochemical changes in rainbow trout (Oncorhynchus mykiss during cold storage

    Directory of Open Access Journals (Sweden)

    František Ježek

    2014-01-01

    Full Text Available The aim of the study was to monitor changes in selected physical (awwater activity, pH values and chemical (TVBN total volatile basic nitrogen, TMA-N trimethylamine nitrogen, FFA free fatty acids, PV peroxide values, TBA thiobarbituric acid value properties in the shelf life of rainbow trout (Oncorhynchus mykiss muscle. A total of 192 trout were examined. Control samples (96 samples were simply packaged in contact with atmospheric oxygen, while experimental samples (96 samples were packaged in a commercial vacuum (98%. All the samples were stored at 2 ± 2° C for 11 days. Analyses were performed on storage days 1, 2, 4, 7, 9, and 11. During the experiment, aw values increased in both types of packaging (in air: 0.982; vacuum-packaged: 0.989. At the end of storage, TVBN and TMA concentrations were at 28.88 ± 4.42 and 19.28 ± 3.00 g mg·100-1, respectively, in the muscle of vacuum-packaged trout; and at 30.52 ± 2.91 and 19.94 ± 2.05 mg·100 g-1, respectively, in fish in simple packaging. The FFA content in vacuum-packaged fish initially declined before increasing to 3.67 ± 2.37% of total fat as oleic acid later in the experiment. The pattern of PV changes was inconclusive, and significant changes (P -1 in vacuum-packaged fish and to 26.03 ± 8.00 mg·kg-1 in fish in simple packaging. Free fatty acids are not a good indicator of spoilage because they are converted to hydroperoxides. Vacuum packaging effectively slowed down oxidative changes in rainbow trout muscle. The peroxide content is not a suitable indicator of shelf life as peroxides are decomposed to secondary products. Total volatile basic nitrogen and thiobarbituric acid value can be recommended as suitable indicators of freshness and shelf life.

  14. BRANCHIAL ELIMINATION OF SUPERHYDROPHOBIC ORGANIC COMPOUNDS BY RAINBOW TROUT (ONCORHYNCHUS MYKISS)

    Science.gov (United States)

    The branchial elimination of pentachloroethane and four congeneric polychlorinated bephenyls by rainbow trout was measured using a fish respirometer-metabolism chamber and an adsorption resin column. Branchial elimination was characterized by calculating a set of apparent in vivo...

  15. Immunization of rainbow trout Oncorhynchus mykiss (Walbaum) with a crude lipopolysaccharide extract from Flavobacterium psychrophilum

    Science.gov (United States)

    Control methods for Flavobacterium psychrophilum, the etiologic agent of bacterial coldwater disease (CWD) and rainbow trout fry syndrome, are limited and oftentimes ineffective; hence, research efforts have focused on vaccine development. This study tested the hypothesis that a crude lipopolysacch...

  16. Determination of metabolic stability using cryopreserved hepatocytes from rainbow trout (Oncorhynchus mykiss)

    Science.gov (United States)

    Standard protocols for isolating, cryopreserving, and thawing rainbow trout hepatocytes are described, along with procedures for using fresh or cryopreserved hepatocytes to assess chemical metabolic stability in fish by means of a substrate depletion approach. Variations on thes...

  17. Inheritance of rainbow trout Oncorhynchus mykiss spleen size and correlation with bacterial cold water disease resistance

    Science.gov (United States)

    Infectious disease causes substantial loss in aquaculture and selective breeding for increased innate resistance offers an attractive strategy for controlling disease. In 2005, the NCCCWA implemented a selective breeding program to increase rainbow trout survival following challenge with Flavobacte...

  18. Intersex occurrence in rainbow trout (Oncorhynchus mykiss male fry chronically exposed to ethynylestradiol.

    Directory of Open Access Journals (Sweden)

    Sophie Depiereux

    Full Text Available This study aimed to investigate the male-to-female morphological and physiological transdifferentiation process in rainbow trout (Oncorhynchus mykiss exposed to exogenous estrogens. The first objective was to elucidate whether trout develop intersex gonads under exposure to low levels of estrogen. To this end, the gonads of an all-male population of fry exposed chronically (from 60 to 136 days post fertilization--dpf to several doses (from environmentally relevant 0.01 µg/L to supra-environmental levels: 0.1, 1 and 10 µg/L of the potent synthetic estrogen ethynylestradiol (EE2 were examined histologically. The morphological evaluations were underpinned by the analysis of gonad steroid (testosterone, estradiol and 11-ketotestosterone levels and of brain and gonad gene expression, including estrogen-responsive genes and genes involved in sex differentiation in (gonads: cyp19a1a, ER isoforms, vtg, dmrt1, sox9a2; sdY; cyp11b; brain: cyp19a1b, ER isoforms. Intersex gonads were observed from the first concentration used (0.01 µg EE2/L and sexual inversion could be detected from 0.1 µg EE2/L. This was accompanied by a linear decrease in 11-KT levels, whereas no effect on E2 and T levels was observed. Q-PCR results from the gonads showed downregulation of testicular markers (dmrt1, sox9a2; sdY; cyp11b with increasing EE2 exposure concentrations, and upregulation of the female vtg gene. No evidence was found for a direct involvement of aromatase in the sex conversion process. The results from this study provide evidence that gonads of male trout respond to estrogen exposure by intersex formation and, with increasing concentration, by morphological and physiological conversion to phenotypic ovaries. However, supra-environmental estrogen concentrations are needed to induce these changes.

  19. Effects of treated sewage effluent on immune function in rainbow trout (Oncorhynchus mykiss)

    Energy Technology Data Exchange (ETDEWEB)

    Hoeger, Birgit [Environmental Toxicology, University of Konstanz, P.O. Box X918, D-78457 Constance (Germany); Heuvel, Michael R. van den [Forest Research, Private Bag 3020, Sala St., Rotorua (New Zealand); Hitzfeld, Bettina C. [Swiss Agency for the Environment, Forests and Landscape (SAEFL), Substances, Soil, Biotechnology Division, Section Substances, 3003 Bern (Switzerland); Dietrich, Daniel R. [Environmental Toxicology, University of Konstanz, P.O. Box X918, D-78457 Constance (Germany)]. E-mail: daniel.dietrich@uni-konstanz.de

    2004-12-20

    In this study, the immune reactions of rainbow trout (Oncorhynchus mykiss) were examined, after exposure to 10, 30 and 70% of tertiary-treated municipal sewage effluent for 27 days. Exposures were conducted concurrently with and without an immune challenge using intraperitoneal injections of inactivated Aeromonas salmonicida salmonicida. Due to the time required to prepare and analyse samples, fish sampling was conducted over two consecutive days. There was no trout mortality for any of the experimental treatments. The exposure to effluent increased in vitro lymphocyte proliferation, decreased circulating lymphocytes and increased degrading erythrocytes in peripheral blood samples. Circulating lymphocytes were only decreased in the sham-injected, but not in the A. salmonicida-injected group. In addition to effluent effects, circulating lymphocytes and lymphocyte proliferation were decreased on day 2 of sampling as compared to day 1. Concentration-dependent degradation of erythrocytes was only observed on day 2 of sampling. Capture and removal of trout on day 1 of sampling presumably caused low-level stress that affected some results on day 2. Oxidative burst, phagocytosis, lysozyme, leucocyte populations other than lymphocytes and A. salmonicida-specific IgM production were not affected by exposure to effluent, and of these parameters, only oxidative burst and total leucocytes showed sampling day effects. From these results it can be observed, that with the exception of oxidative burst, those variables affected by effluent exposure were also significantly changed by the low-level sampling stress imposed by staggered sampling. Elevated liver mixed-function oxygenase activity as measured by 7-ethoxyresorufin-O-deethylase activity, and increased bile polycyclic aromatic hydrocarbon (PAH) metabolites were observed in response to sewage effluent exposure. As both PAHs and stress are known immune suppressors, it is difficult to conclude whether or not changes in immune

  20. Effects of treated sewage effluent on immune function in rainbow trout (Oncorhynchus mykiss)

    International Nuclear Information System (INIS)

    Hoeger, Birgit; Heuvel, Michael R. van den; Hitzfeld, Bettina C.; Dietrich, Daniel R.

    2004-01-01

    In this study, the immune reactions of rainbow trout (Oncorhynchus mykiss) were examined, after exposure to 10, 30 and 70% of tertiary-treated municipal sewage effluent for 27 days. Exposures were conducted concurrently with and without an immune challenge using intraperitoneal injections of inactivated Aeromonas salmonicida salmonicida. Due to the time required to prepare and analyse samples, fish sampling was conducted over two consecutive days. There was no trout mortality for any of the experimental treatments. The exposure to effluent increased in vitro lymphocyte proliferation, decreased circulating lymphocytes and increased degrading erythrocytes in peripheral blood samples. Circulating lymphocytes were only decreased in the sham-injected, but not in the A. salmonicida-injected group. In addition to effluent effects, circulating lymphocytes and lymphocyte proliferation were decreased on day 2 of sampling as compared to day 1. Concentration-dependent degradation of erythrocytes was only observed on day 2 of sampling. Capture and removal of trout on day 1 of sampling presumably caused low-level stress that affected some results on day 2. Oxidative burst, phagocytosis, lysozyme, leucocyte populations other than lymphocytes and A. salmonicida-specific IgM production were not affected by exposure to effluent, and of these parameters, only oxidative burst and total leucocytes showed sampling day effects. From these results it can be observed, that with the exception of oxidative burst, those variables affected by effluent exposure were also significantly changed by the low-level sampling stress imposed by staggered sampling. Elevated liver mixed-function oxygenase activity as measured by 7-ethoxyresorufin-O-deethylase activity, and increased bile polycyclic aromatic hydrocarbon (PAH) metabolites were observed in response to sewage effluent exposure. As both PAHs and stress are known immune suppressors, it is difficult to conclude whether or not changes in immune

  1. Intersex Occurrence in Rainbow Trout (Oncorhynchus mykiss) Male Fry Chronically Exposed to Ethynylestradiol

    Science.gov (United States)

    Depiereux, Sophie; Liagre, Mélanie; Danis, Lorraine; De Meulder, Bertrand; Depiereux, Eric; Segner, Helmut; Kestemont, Patrick

    2014-01-01

    This study aimed to investigate the male-to-female morphological and physiological transdifferentiation process in rainbow trout (Oncorhynchus mykiss) exposed to exogenous estrogens. The first objective was to elucidate whether trout develop intersex gonads under exposure to low levels of estrogen. To this end, the gonads of an all-male population of fry exposed chronically (from 60 to 136 days post fertilization – dpf) to several doses (from environmentally relevant 0.01 µg/L to supra-environmental levels: 0.1, 1 and 10 µg/L) of the potent synthetic estrogen ethynylestradiol (EE2) were examined histologically. The morphological evaluations were underpinned by the analysis of gonad steroid (testosterone, estradiol and 11-ketotestosterone) levels and of brain and gonad gene expression, including estrogen-responsive genes and genes involved in sex differentiation in (gonads: cyp19a1a, ER isoforms, vtg, dmrt1, sox9a2; sdY; cyp11b; brain: cyp19a1b, ER isoforms). Intersex gonads were observed from the first concentration used (0.01 µg EE2/L) and sexual inversion could be detected from 0.1 µg EE2/L. This was accompanied by a linear decrease in 11-KT levels, whereas no effect on E2 and T levels was observed. Q-PCR results from the gonads showed downregulation of testicular markers (dmrt1, sox9a2; sdY; cyp11b) with increasing EE2 exposure concentrations, and upregulation of the female vtg gene. No evidence was found for a direct involvement of aromatase in the sex conversion process. The results from this study provide evidence that gonads of male trout respond to estrogen exposure by intersex formation and, with increasing concentration, by morphological and physiological conversion to phenotypic ovaries. However, supra-environmental estrogen concentrations are needed to induce these changes. PMID:25033040

  2. Differences in Bacterial Population in Rainbow Trout (Oncorhynchus mykiss Walbum Fry after Transfer from Incubator to Pools

    Directory of Open Access Journals (Sweden)

    Damir Kapetanović

    2005-01-01

    Full Text Available The microflora of rainbow trout (Oncorhynchus mykiss Walbaum fry from a commercial freshwater hatchery, along with important water quality parameters such as temperature, dissolved oxygen and pH, was analysed. Samples for bacteriological analysis were taken from gill, heart and kidney, from the third to the eighth week after hatching. Pure bacterial colonies were examined macroscopically, with Gram staining and biochemical tests. For final identification, the APILAB Plus programme (bioMérieux, France was used. The bacterial populations of rainbow trout fry changed depending on age. Most of the bacterial colonies were cultured from the gills (64.4 %, rather than the heart (21.8 % and kidney (13.8 %. The bacterial community of fry gills from an incubator was composed mostly of Gram-positive bacteria such as Renibacterium salmoninarum, Lactobacillus spp., Staphylococcus spp. and Corynebacterium aquaticum. After the transfer of fry from incubator into the pools the Gram-negative bacteria increased in number and became the dominant microflora of rainbow trout fry and comprised more than 95 % of its bacterial flora. Flavibacterium, Acinetobacter and Yersinia were the predominant Gram-negative genera in fry in the incubator, whereas Aeromonas and Pseudomonas were the main isolates from rainbow trout fry until the end of the experiment.

  3. Immune response, stress resistance and bacterial challenge in juvenile rainbow trouts Oncorhynchus mykiss fed diets containing chitosan-oligosaccharides

    Directory of Open Access Journals (Sweden)

    Lin LUO, Xuefeng CAI, Chuan HE, Min XUE, Xiufeng WU , Haining CAO

    2009-12-01

    Full Text Available Effects of dietary supplementation of chitosan-oligosaccharides (COS on the growth performance, immune response, stress resistance, and disease resistance of juvenile rainbow trout Oncorhynchus mykiss were studied. Four experimental diets containing 0, 20, 40, or 60 mg/kg COS (COS0, COS20, COS40, and COS60, respectively were fed to juvenile rainbow trout (initial weight = 5.2 ± 0.3 g for 8 weeks. By the end of the feeding trial, representative groups of fish from each dietary treatment were challenged with stressor (30 sec air exposure and pathogen exposure (intraperitoneal injection with Aeromonas hydrophila. Results showed that supplementation of COS in diets did not affect production performance and body composition of rainbow trout. However, fish fed the COS40 diet demonstrated improved phagocytic activities, respiratory burst activities and decreased serum cortisol level. Additionally, survival following A. hydrophila challenge was significant higher among fish fed the COS-supplemented feeds, although there was no difference based on the level of supplementation. The present study suggests that COS can be used as an immuno-stimulant in rainbow trout feeds [Current Zoology 55 (6: 416– 422, 2009].

  4. Biological control of Aeromonas salmonicida subsp. salmonicida infection in rainbow trout (Oncorhynchus mykiss) using Aeromonas phage PAS-1.

    Science.gov (United States)

    Kim, J H; Choresca, C H; Shin, S P; Han, J E; Jun, J W; Park, S C

    2015-02-01

    The potential control efficacy of Aeromonas phage PAS-1 was evaluated against Aeromonas salmonicida subsp. salmonicida infection in rainbow trout (Oncorhynchus mykiss) model in this study. The phage was co-cultured with the virulent A. salmonicida subsp. salmonicida strain AS05 that possesses the type III secretion system (TTSS) ascV gene, and efficient bacteriolytic activity was observed against the bacteria. The administration of PAS-1 in rainbow trout demonstrated that the phage was cleared from the fish within 200 h post-administration, and a temporal neutralizing activity against the phage was detected in the sera of phage-administrated fish. The administration of PAS-1 (multiplicity of infection: 10 000) in A. salmonicida subsp. salmonicida infected rainbow trout model showed notable protective effects, with increased survival rates and mean times to death. These results demonstrated that Aeromonas phage PAS-1 could be considered as an alternative biological control agent against A. salmonicida subsp. salmonicida infections in rainbow trout culture. © 2013 Blackwell Verlag GmbH.

  5. Oxidative stability during storage of fish oil from filleting by-products of rainbow trout (Oncorhynchus mykiss) is largely independent of the processing and production temperature

    DEFF Research Database (Denmark)

    Honold, Philipp; Nouard, Marie-Louise; Jacobsen, Charlotte

    2016-01-01

    Rainbow trout (Oncorhynchus mykiss) is the main fish species produced in Danish fresh water farming. Large amounts of fileting by-products like heads, bones, tails (HBT), and intestines are produced when rainbow trout is processed to smoked rainbow trout filets. The filleting by-products can...... be used to produce high quality fish oil. In this study, the oxidative stability of fish oil produced from filleting by-products was evaluated. The oil was produced from conventional or organic fish (low and high omega-3 fatty acid content) at different temperatures (70 and 90°C). The oxidative stability...

  6. Cloning and characterization of transferrin cDNA and rapid detection of transferrin gene polymorphism in rainbow trout (Oncorhynchus mykiss).

    Science.gov (United States)

    Tange, N; Jong-Young, L; Mikawa, N; Hirono, I; Aoki, T

    1997-12-01

    A cDNA clone of rainbow trout (Oncorhynchus mykiss) transferrin was obtained from a liver cDNA library. The 2537-bp cDNA sequence contained an open reading frame encoding 691 amino acids and the 5' and 3' noncoding regions. The amino acid sequences at the iron-binding sites and the two N-linked glycosylation sites, and the cysteine residues were consistent with known, conserved vertebrate transferrin cDNA sequences. Single N-linked glycosylation sites existed on the N- and C-lobe. The deduced amino acid sequence of the rainbow trout transferrin cDNA had 92.9% identities with transferrin of coho salmon (Oncorhynchus kisutch); 85%, Atlantic salmon (Salmo salar); 67.3%, medaka (Oryzias latipes); 61.3% Atlantic cod (Gadus morhua); and 59.7%, Japanese flounder (Paralichthys olivaceus). The long and accurate polymerase chain reaction (LA-PCR) was used to amplify approximately 6.5 kb of the transferrin gene from rainbow trout genomic DNA. Restriction fragment length polymorphisms (RFLPs) of the LA-PCR products revealed three digestion patterns in 22 samples.

  7. Assessment of metabolic stability using the rainbow trout (Oncorhynchus mykiss) liver S9 fraction

    Science.gov (United States)

    Standard protocols are given for assessing metabolic stability in rainbow trout using the liver S9 fraction. These protocols describe the isolation of S9 fractions from trout livers, evaluation of metabolic stability using a substrate depletion approach, and expression of the res...

  8. A comparison of oxolinic acid concentrations in farmed and laboratory held rainbow trout ( Oncorhynchus mykiss ) following oral therapy

    DEFF Research Database (Denmark)

    Coyne, R.; Samuelsen, O.; Kongshaug, H.

    2004-01-01

    Plasma oxolinic acid (OXA) concentrations were measured in fish from a cage of farmed rainbow trout (Oncorhynchus mykiss) 1 day after the termination of medication. The fish were experiencing significant mortalities and following a diagnosis of vibriosis, OXA had been orally administered at 50 mg....../kg for 6 days over a 9-day period. Samples from healthy fish (n=20), moribund (n=26) and dead fish (n=10) were analysed by HPLC. There was a dramatic difference in the OXA concentrations between healthy and moribund fish. In the moribund group, none of which showed signs of recent feeding, 85% of the fish...... laboratory held rainbow trout (O. mykiss) following the administration of OXA under similar conditions of salinity, temperature and dosing regimen. In these laboratory held fish, the mean plasma OXA concentration was 0.133±0.068 mg/l. The major difference between the distributions of OXA concentrations...

  9. Effects of atrazine on hepatic metabolism and endocrine homeostasis in rainbow trout (Oncorhynchus mykiss)

    International Nuclear Information System (INIS)

    Salaberria, Iurgi; Hansen, Bjorn Henrik; Asensio, Vega; Olsvik, Pal A.; Andersen, Rolf A.; Jenssen, Bjorn Munro

    2009-01-01

    The herbicide atrazine (ATZ) is one of the most widely used pesticides in the world and is now under scrutiny for its alleged capacity to disrupt the endocrine system. Exhibiting negligible interaction with the estrogen receptor (ER), ATZ's mode of action remains to be elucidated. ATZ may act as an inducer of the enzyme aromatase, which converts androgens to estrogens, although other mechanisms should also be taken into consideration such as impairment of hepatic metabolism. Therefore we administered juvenile rainbow trout (Oncorhynchus mykiss) a dose of either 2 or 200 μg ATZ/kg, or of carrier control phosphate buffered saline (PBS) and we measured plasma concentrations of testosterone (T), 17beta-estradiol (E2) and vitellogenin (Vtg) 6 days after exposure. Simultaneously we analyzed hepatic gene expression of cytochrome P450 (CYP) 1A and pi-class glutathione S-transferase (GST-P), and catalase (CAT) activity. Although sex steroid levels showed no significant alterations, we found a dose-dependent increase in Vtg and a concomitant decrease in CYP1A. There was no effect of ATZ on GST-P mRNA levels but GST-P was positively correlated with CYP1A. Also, CYP1A was negatively correlated with liver CAT and E2, and varied with T concentrations in a hormetic manner. The results showed that ATZ can alter hepatic metabolism, induce estrogenic effects and oxidative stress in vivo, and that these effects are linked

  10. Growth depression in socially subordinate rainbow trout Oncorhynchus mykiss: more than a fasting effect.

    Science.gov (United States)

    DiBattista, Joseph D; Levesque, Haude M; Moon, Thomas W; Gilmour, Kathleen M

    2006-01-01

    To assess the effects of subordinate social status on digestive function, metabolism, and enzyme activity in salmonid fish, juvenile rainbow trout Oncorhynchus mykiss were paired with size-matched conspecifics (digestive function reflects in large part a lack of feeding. Hepatic phosphoenolpyruvate carboxykinase activity was significantly higher in subordinate fish relative to dominants, whereas subordinate hepatic pyruvate kinase activity was significantly lower; activities of both enzymes were significantly correlated with plasma cortisol concentrations and behavior scores. Dominant-subordinate differences in the activities of these enzymes were eliminated by administration of the glucocorticoid receptor antagonist RU486, underlining a role for circulating cortisol in eliciting the differences. Significant increases relative to control fish were also detected in red and white muscles from subordinate fish in the activities of protein catabolic enzymes (aspartate aminotransferase, alanine aminotransferase, glutamate dehydrogenase). These differences occurred in the absence of any change in plasma free amino acid or ammonia concentrations, supporting an enhanced turnover of amino acids in muscle in subordinate fish. The results support the hypothesis that changes in metabolism, beyond those elicited by low food consumption, may be responsible at least in part for the low growth rates typical of subordinate fish and that these changes may be related specifically to circulating cortisol levels in subordinate fish.

  11. Antibacterial activity of Iranian medicinal plants against Streptococcus iniae isolated from rainbow trout (Oncorhynchus mykiss

    Directory of Open Access Journals (Sweden)

    Pirbalouti Ghasemi Abdollah

    2011-01-01

    Full Text Available Streptococcus iniae is among the major pathogens of a large number of fish species cultured in fresh and marine recirculating and net pen production systems. Ten Iranian medicinal plants were assessed for their antimicrobial activity against Streptococcus iniae isolates obtained from diseased Oncorhynchus mykiss (Salmonidae; Walbaum, 1972 collected from fish farms in Iran. The antibacterial activity of ethanol extracts of Punica granatum, Quercus branti, Glycyrrhiza glabra and essential oils of Heracleum lasiopetalum, Satureja bachtiarica, Thymus daenensis, Myrtus communis, Echinophora platyloba, Kelussia odoratissima and Stachys lavandulifolia against Steptococcus iniae was evaluated by disc diffusion and serial dilution assays. Most of the extracts and essential oils showed a relatively high antibacterial activity against Streptococcus iniae. Of the plants studied, the most active extracts were those obtained from the essential oils of Satureja bachtiarica, Echinophora platyloba, Thymus daenensis and the ethanol extract of Quercus branti. Some of the extracts were active against Streptococcus iniae. Two essential oils showed lower MIC values; Heracleum lasiopetalum (78 μg/ml and Satureja bachtiarica (39 μg/ml. The essential oil of Satureja bachtiarica could be an important source of antibacterial compounds against the Streptococcus iniae isolated from rainbow trout.

  12. Effect of nanosilver on metabolism in rainbow trout (Oncorhynchus mykiss): An investigation using different respirometric approches

    DEFF Research Database (Denmark)

    Murray, Laura; Rennie, Michael D.; Svendsen, Jon Christian

    2017-01-01

    gene expression, gill damage, and impaired gas exchange, as well as mortality at high nAg concentrations. The present study reports the effects of nAg on the metabolism of rainbow trout (Oncorhynchus mykiss). Fish were exposed to environmentally relevant concentrations (0.28 ± 0.02 μg/L) and higher (47.......60 ± 5.13 μg/L) for 28 d, after which their standard metabolic rate (SMR), forced maximum metabolic rate (MMRf), and spontaneous maximum metabolic rate (MMRs) were measured. There was no effect observed in SMR, MMRf, or MMRs, suggesting that nAg is unlikely to directly affect fish metabolism. On average......, MMRs tended to be greater than MMRf, and most MMRs occurred when room lighting increased. The timing of MMRf chase protocols was found to affect both MMRf and SMR estimates, in that chasing fish before respirometric experiments caused higher MMRf estimates and lower SMR estimates. Although compounded...

  13. Metabolic pathways of decabromodiphenyl ether (BDE209) in rainbow trout (Oncorhynchus mykiss) via intraperitoneal injection.

    Science.gov (United States)

    Feng, Chenglian; Xu, Yiping; Zha, Jinmiao; Li, Jian; Wu, Fengchang; Wang, Zijian

    2015-03-01

    Decabromodiphenyl ether (BDE209) was of great concern due to its biotransformation in different organisms. However, most studies devoted to the metabolic intermediates of BDE209, less has been done on the metabolic pathways in vivo, especially on the relationships among debrominated-BDEs, OH-BDEs and MeO-BDEs. In this study, the metabolic pathways and intermediates of BDE209 in rainbow trout (Oncorhynchus mykiss) were investigated, and the time-dependent transformations of the metabolites were also examined. The primary debrominated metabolites were BDE47, 49, 99, 197, 207; the main MeO-BDEs were MeO-BDE47, MeO-BDE68 and MeO-BDE100; OH-BDEs were primarily composed of OH-BDE28 and OH-BDE42. From the time-dependent and dose-effect relationships, the debromination should be followed by hydroxylation, and then by methoxylation. The increasing in body burden of MeO-BDEs corresponded to the decreasing of OH-BDEs, which could indirectly prove the inter-conversion between OH-BDEs and MeO-BDEs. This study would motivate the future research of toxicological mechanisms of BDEs. Copyright © 2015 Elsevier B.V. All rights reserved.

  14. Effects of Watercress (Nasturtium nasturtium extract on selected immunological parameters of rainbow trout (Oncorhynchus mykiss

    Directory of Open Access Journals (Sweden)

    K. Ahmadi

    2012-05-01

    Full Text Available Watercress (Nasturtium nasturtium is a medical plant containing diverse chemically-active substances with biological properties. The present study was conducted to investigate the immunomodulatory effects of watercress extract on immunological and hematological parameters of rainbow trout (Oncorhynchus mykiss. Fish were fed for 21 days with diet supplemented with 0.1% and 1% of watercress extract per 1 kg food and with a normal diet as control. Hematological parameters such as red blood cells (RBC and white blood cells (WBC, hematocrit (Hct, hemoglobin (Hb, RBC index like mean corpuscular volume (MCV, mean corpuscular hemoglobin (MCH and mean corpuscular hemoglobin concentration (MCHC as well as immunological parameters such as peroxidase, lysozyme and complement activities, total protein, albumin and globulin levels were measured after 21 days of watercress extract treatment. The results indicated that oral administration of 1 % watercress extract in fish may enhance some hematological and immunological parameters including Hb and MCHC, lysozyme and complement activities, total protein and globulin levels, compared to the controls after 21 days of experimental period. In conclusion, on the basis of these results, oral administration of watercress extract may be useful to improve fish’s immune system.

  15. Nitrogen waste from rainbow trout (Oncorhynchus mykiss) with particular focus on urea

    DEFF Research Database (Denmark)

    Dalsgaard, Anne Johanne Tang; Larsen, Bodil Katrine; Pedersen, Per Bovbjerg

    2015-01-01

    a laboratory, mass-balance approach, the current study examined the effects of commercially applied feeding levels on the loading of different N waste forms, including daily fluctuations in dissolved total nitrogen (TN), total ammonia nitrogen (TAN), urea-N, and non-characterized, dissolved N deriving from...... juvenile rainbow trout (Oncorhynchus mykiss). In addition, the study examined whether there was a removal of urea-N across a moving bed biofilter operated as end-of-pipe under commercial conditions. The laboratory, mass-balance study showed that there were no effects of feeding levels (1.3, 1.5 or 1....../nitrogen. Results from the commercially operated, nitrifying biofilter showed that urea-N was removed at a rate of 0.014 g N m2 day−1. Compared to the removal of TAN (0.208 g N m2 day−1), the moving bed biofilter was 1.07 times more active in removing dissolved N than immediately expected when only considering TAN...

  16. Characterizing creosote immunotoxicity in rainbow trout, Oncorhynchus mykiss: A mesocosm study

    Energy Technology Data Exchange (ETDEWEB)

    Karrow, N.A.; Dixon, D.G.; Bols, N.C.; Whyte, J.J.; Magdic, S. [Univ. of Waterloo, Ontario (Canada); Boermans, H.J.; Solomon, K.R. [Univ. of Guelph, Ontario (Canada)

    1995-12-31

    Immunocompetence was assessed in rainbow trout Oncorhynchus mykiss exposed on days 103 to 131 of a mesocosm study using initial liquid creosote concentrations of 0, 5, 9, 17, 31 and 56 ul/l. Oxidative burst, phagocytic activity, and lymphocyte blastogenic response were measured, as indicators of exposure, using pronephros leukocytes. Peripheral blood was used to measure surface immunoglobulin-positive (slg{sup +}) leukocyte count and lysozyme activity. Tissue residue and water concentration were used as dose surrogates. Pronephros leukocyte phagocytic activity and oxidative burst exhibited a significant dose-response relationship, as measured by flow cytometry. Oxidative burst was inhibited, while phagocytic activity was enhanced. A concentration dependent reduction in the number of slg + peripheral blood leukocytes was also observed using flow cytometry. Although no measurable change in lymphocyte proliferation was detected in response to phytohaemagglutinin (PHA) and concanavalin-A (ConA), lipopolysaccharide (LPS) induced blastogenesis was significantly inhibited. No change in lysozyme activity was observed at 28 d. The results from this study indicate that sediment bound creosote has the potential to alter immune response. Polycyclic aromatic hydrocarbons (PAHs), a major constituent of liquid creosote, are the suspected immunoalterating agents. PAHs are known to predispose fish to disease resulting from their immunosuppressive potentiality.

  17. A bioinformatics-based update on microRNAs and their targets in rainbow trout (Oncorhynchus mykiss).

    Science.gov (United States)

    Yang, Liandong; He, Shunping

    2014-01-01

    MicroRNAs (miRNAs) participate in various vitally biological processes via controlling target genes activity and thousands of miRNAs have been identified in many species to date, including 18,698 known animal miRNA in miRBase. However, there are only limited studies reported in rainbow trout (Oncorhynchus mykiss) especially via the computational-based approaches. In present study, we systematically investigated the miRNAs in rainbow trout using a well-developed comparative genome-based homologue search. A total of 196 potential miRNAs, belonging to 124 miRNA families, were identified, most of which were firstly reported in rainbow trout. The length of miRNAs ranged from 17 to 24 nt with an average of 20 nt while the length of their precursors varied from 47 to 152 nt with an average of 85 nt. The identified miRNAs were not evenly distributed in each miRNA family, with only one member per family for a majority, and multiple members were also identified for several families. Nucleotide U was dominant in the pre-miRNAs with a percentage of 30.04%. The rainbow trout pre-miRNAs had relatively high negative minimal folding free energy (MFE) and adjusted MFE (AMFE). Not only the mature miRNAs but their precursor sequences are conserved among the living organisms. About 2466 O. mykiss genes were predicted as potential targets for 189 miRNAs. Gene Ontology (GO) analysis showed that nearly 2093, 2107, and 2081 target genes are involved in cellular component, molecular function, and biological processes respectively. KEGG pathway enrichment analysis illuminated that these miRNAs targets might regulate 105 metabolic pathways, including those of purine metabolism, nitrogen metabolism, and oxidative phosphorylation. This study has provided an update on rainbow trout miRNAs and their targets, which represents a foundation for future studies. © 2013.

  18. Localization of rem2 in the central nervous system of the adult rainbow trout (Oncorhynchus mykiss).

    Science.gov (United States)

    Downs, Anna G; Scholles, Katie R; Hollis, David M

    2016-12-01

    Rem2 is member of the RGK (Rem, Rad, and Gem/Kir) subfamily of the Ras superfamily of GTP binding proteins known to influence Ca 2+ entry into the cell. In addition, Rem2, which is found at high levels in the vertebrate brain, is also implicated in cell proliferation and synapse formation. Though the specific, regional localization of Rem2 in the adult mammalian central nervous system has been well-described, such information is lacking in other vertebrates. Rem2 is involved in neuronal processes where the capacities between adults of different vertebrate classes vary. Thus, we sought to localize the rem2 gene in the central nervous system of an adult anamniotic vertebrate, the rainbow trout (Oncorhynchus mykiss). In situ hybridization using a digoxigenin (DIG)-labeled RNA probe was used to identify the regional distribution of rem2 expression throughout the trout central nervous system, while real-time polymerase chain reaction (rtPCR) further supported these findings. Based on in situ hybridization, the regional distribution of rem2 occurred within each major subdivision of the brain and included large populations of rem2 expressing cells in the dorsal telencephalon of the cerebrum, the internal cellular layer of the olfactory bulb, and the optic tectum of the midbrain. In contrast, no rem2 expressing cells were resolved within the cerebellum. These results were corroborated by rtPCR, where differential rem2 expression occurred between the major subdivisions assayed with the highest levels being found in the cerebrum, while it was nearly absent in the cerebellum. These data indicate that rem2 gene expression is broadly distributed and likely influences diverse functions in the adult fish central nervous system. Copyright © 2016 Elsevier B.V. All rights reserved.

  19. Suppression of aggression in rainbow trout (Oncorhynchus mykiss) by dietary L-tryptophan.

    Science.gov (United States)

    Winberg, S; Øverli, Ø; Lepage, O

    2001-11-01

    Juvenile rainbow trout Oncorhynchus mykiss were isolated in individual compartments in observation aquaria and allowed to acclimate for 1 week, during which they were fed commercial trout feed. Thereafter, the fish were tested for aggressive behaviour using a resident/intruder test. Following this first resident/intruder test, the feed was exchanged for an experimental wet feed supplemented with 0.15 % or 1.5 % L-tryptophan (by wet mass). Controls received the same feed but without L-tryptophan supplementation. The fish were fed to satiety daily, and their individual feed intake was recorded. Aggressive behaviour was quantified again after 3 and 7 days of L-tryptophan feeding using the resident/intruder test. Feeding the fish L-tryptophan-supplemented feed for 3 days had no effect on aggressive behaviour, whereas feeding the fish L-tryptophan-supplemented feed for 7 days significantly suppressed aggressive behaviour in the fish, an effect seen at both levels of L-tryptophan supplementation. Fish fed L-tryptophan-supplemented feed showed elevated plasma and brain levels of L-tryptophan. The amino acid L-tryptophan is the precursor of serotonin, and supplementary dietary L-tryptophan was found to elevate levels of 5-hydroxyindoleacetic acid (5-HIAA) and the 5-HIAA/serotonin concentration ratio in the brain. Neither feed intake nor plasma cortisol level was significantly affected by dietary L-tryptophan. Central serotonin is believed to have an inhibitory effect on aggressive behaviour, and it is suggested that the suppressive effect of dietary L-tryptophan on aggressive behaviour is mediated by an elevation of brain serotonergic activity.

  20. Differential virulence mechanisms of infectious hematopoietic necrosis virus in rainbow trout (Oncorhynchus mykiss) include host entry and virus replication kinetics

    Science.gov (United States)

    Penaranda, M.M.D.; Purcell, M.K.; Kurath, G.

    2009-01-01

    Host specificity is a phenomenon exhibited by all viruses. For the fish rhabdovirus infectious hematopoietic necrosis virus (IHNV), differential specificity of virus strains from the U and M genogroups has been established both in the field and in experimental challenges. In rainbow trout (Oncorhynchus mykiss), M IHNV strains are consistently more prevalent and more virulent than U IHNV. The basis of the differential ability of these two IHNV genogroups to cause disease in rainbow trout was investigated in live infection challenges with representative U and M IHNV strains. When IHNV was delivered by intraperitoneal injection, the mortality caused by U IHNV increased, indicating that the low virulence of U IHNV is partly due to inefficiency in entering the trout host. Analyses of in vivo replication showed that U IHNV consistently had lower prevalence and lower viral load than M IHNV during the course of infection. In analyses of the host immune response, M IHNV-infected fish consistently had higher and longer expression of innate immune-related genes such as Mx-1. This suggests that the higher virulence of M IHNV is not due to suppression of the immune response in rainbow trout. Taken together, the results support a kinetics hypothesis wherein faster replication enables M IHNV to rapidly achieve a threshold level of virus necessary to override the strong host innate immune response. ?? 2009 SGM.

  1. Mapping of five candidate sex-determining loci in rainbow trout (Oncorhynchus mykiss

    Directory of Open Access Journals (Sweden)

    Drew Robert E

    2009-01-01

    Full Text Available Abstract Background Rainbow trout have an XX/XY genetic mechanism of sex determination where males are the heterogametic sex. The homology of the sex-determining gene (SDG in medaka to Dmrt1 suggested that SDGs evolve from downstream genes by gene duplication. Orthologous sequences of the major genes of the mammalian sex determination pathway have been reported in the rainbow trout but the map position for the majority of these genes has not been assigned. Results Five loci of four candidate genes (Amh, Dax1, Dmrt1 and Sox6 were tested for linkage to the Y chromosome of rainbow trout. We exclude the role of all these loci as candidates for the primary SDG in this species. Sox6i and Sox6ii, duplicated copies of Sox6, mapped to homeologous linkage groups 10 and 18 respectively. Genotyping fishes of the OSU × Arlee mapping family for Sox6i and Sox6ii alleles indicated that Sox6i locus might be deleted in the Arlee lineage. Conclusion Additional candidate genes should be tested for their linkage to the Y chromosome. Mapping data of duplicated Sox6 loci supports previously suggested homeology between linkage groups 10 and 18. Enrichment of the rainbow trout genomic map with known gene markers allows map comparisons with other salmonids. Mapping of candidate sex-determining loci is important for analyses of potential autosomal modifiers of sex-determination in rainbow trout.

  2. A mechanistic assessment of seasonal microhabitat selection by drift-feeding rainbow trout Oncorhynchus mykiss in a southwestern headwater stream

    Science.gov (United States)

    Kalb, Bradley W.; Huntsman, Brock M.; Caldwell, Colleen A.; Bozek, Michael A.

    2018-01-01

    The positioning of fishes within a riverscape is dependent on the proximity of complementary habitats. In this study, foraging and non-foraging habitat were quantified monthly over an entire year for a rainbow trout (Oncorhynchus mykiss) population in an isolated, headwater stream in southcentral New Mexico. The stream follows a seasonal thermal and hydrologic pattern typical for a Southwestern stream and was deemed suitable for re-introduction of the native and close relative, Rio Grande cutthroat trout (O. clarkii virginalis). However, uncertainty associated with limited habitat needed to be resolved if repatriation of the native fish was to be successful. Habitat was evaluated using resource selection functions with a mechanistic drift-foraging model to explain trout distributions. Macroinvertebrate drift was strongly season- and temperature-dependent (lower in winter and spring, higher in summer and fall). Models identified stream depth as the most limiting factor for habitat selection across seasons and size-classes. Additionally, positions closer to cover were selected during the winter by smaller size-classes (0, 1, 2), while net energy intake was important during the spring for most size-classes (0, 1, 2, 3). Drift-foraging models identified that 81% of observed trout selected positions that could meet maintenance levels throughout the year. Moreover, 40% of selected habitats could sustain maximum growth. Stream positions occupied by rainbow trout were more energetically profitable than random sites regardless of season or size-class. Larger size-classes (3, 4+) were energetically more limited throughout the year than were smaller size-classes. This research suggests that habitat in the form of deep pools is of paramount importance for rainbow trout or native cutthroat trout.

  3. Plump Cutthroat Trout and Thin Rainbow Trout in a Lentic Ecosystem

    OpenAIRE

    Courtney, Joshua; Abbott, Jessica; Schmidt, Kerri; Courtney, Michael

    2012-01-01

    Background: Much has been written about introduced rainbow trout (Oncorhynchus mykiss) interbreeding and outcompeting cutthroat trout (Oncorhynchus clarkii). However, the specific mechanisms by which rainbow trout and their hybrids outcompete cutthroat trout have not been thoroughly explored, and the published data is limited to lotic ecosystems. Materials and Methods: Samples of rainbow trout and cutthroat trout were obtained from a lentic ecosystem by angling. The total length and weight of...

  4. Bioaccumulation of silver nanoparticles in rainbow trout (Oncorhynchus mykiss): Influence of concentration and salinity

    International Nuclear Information System (INIS)

    Salari Joo, Hamid; Kalbassi, Mohammad Reza; Yu, Il Je; Lee, Ji Hyun; Johari, Seyed Ali

    2013-01-01

    Highlights: •We studied influence of concentration and salinity on bioaccumulation of silver nanoparticles in rainbow trout (Oncorhynchus mykiss). •The Ag-NPs were characterized using standard methods. •The organisms were exposed to Ag-NPs in three different salinity concentrations, for 14 days in static renewal systems. •The bioaccumulation of Ag in the studied tissues was concentration-dependent in all the salinities and its order were liver > kidneys ≈ gills > white muscles respectively. -- Abstract: With the increasing use of silver nanoparticles (Ag-NPs), their entrance into aquatic ecosystems is inevitable. Thus, the present study simulated the potential fate, toxicity, and bioaccumulation of Ag-NPs released into aquatic systems with different salinities. The Ag-NPs were characterized using inductively coupled plasma-atomic emission spectroscopy (ICP-AES), dynamic light scattering (DLS), transmission electron microscopy (TEM), energy-dispersive X-ray analysis (EDX), and UV–vis spectroscopy. Juvenile rainbow trout were exposed to Ag-NPs in three different salinity concentrations, including low (0.4 ppt), moderate (6 ± 0.3 ppt), and high (12 ± 0.2 ppt) salinity, for 14 days in static renewal systems. The nominal Ag-NP concentrations in the low salinity were 0.032, 0.1, 0.32, and 1 ppm, while the Ag-NP concentrations in the moderate and high salinity were 3.2, 10, 32, and 100 ppm. UV–vis spectroscopy was used during 48 h (re-dosing time) to evaluate the stability and possible changes in size of the Ag-NPs in the water. The results revealed that the λ max of the Ag-NPs remained stable (415–420 nm) at all concentrations in the low salinity with a reduction of absorbance between 380 and 550 nm. In contrast, the λ max quickly shifted to a longer wavelength and reduced absorbance in the moderate and higher salinity. The bioaccumulation of Ag in the studied tissues was concentration-dependent in all the salinities based on the following order

  5. Extrahepatic disposition of 3H-aflatoxin B1 in the rainbow trout (Oncorhynchus mykiss)

    International Nuclear Information System (INIS)

    Larsson, P.; Tjaelve, H.; Ngethe, S.; Ingebrigtsen, K.

    1992-01-01

    Whole-body autoradiography in rainbow trout (Oncorhynchus mykiss) after oral and intravenous administration of 3 H-labelled aflation B 1 showed labelling of several extrahepatic tissues, such as the uveal melanin and the vitreous humour of the eyes, the trunk and head kidney, the olfactory rosettes and the pyloric caecae. Liquid chromatography of extracts of the vitreous humour showed that unmetabolized 3 H-AFB 1 was the main labelled material present at this site. Liquid chromatography of extracts of the uveal melanin showed presence of aflatoxicol and aflatoxin B 1 in proportions of about 3:1. The binding to the pigment is probably due to a hydrophobic type of interaction with the melanin. Microautoradiography showed that melanin-containing cells in the trunk and head kidney and in the olfactory rosettes also accumulated high amounts of radioactivity. In the trunk kidney there was, in addition, a labelling of the second segment of the proximal tubules and of the distal tubules and the collecting ducts. Studies in vitro with microsomal and 12,000xg supernatant preparations of the trunk kidney showed formation of DNA- and protein-bound metabolites from the aflatoxin B 1 . It is probable that the bioactivation of the aflatoxin B 1 is confined to the second segment of the proximal tubules. The labelling of the distal tubules and the collecting ducts, which was confined to the cytoplasm of the cells, may be related to excretion and/or absorption processes. Microautoradiography of the olfactory rosettes, showed labelling of the sensory epithelium, but not the indifferent epithelium. A low formation of protein-bound aflatoxin B 1 -metabolites was found in incubations with microsomal preparations of this tissue. The same observation was made in incubations with microsomal preparations of the head kidney. In the pyloric caeca bound metabolites were observed in vivo at a level comparable to that found in the trunk kidney. Our results suggest that retention and metabolism

  6. Subcellular interactions of dietary cadmium, copper and zinc in rainbow trout (Oncorhynchus mykiss)

    International Nuclear Information System (INIS)

    Kamunde, Collins; MacPhail, Ruth

    2011-01-01

    Highlights: Interactions of Cu, Cd and Zn were studied at the subcellular level in rainbow trout. Metals accumulated in the liver were predominantly metabolically active. Cd, Cu and Zn exhibited both competitive and cooperative interactions. The metal–metal interactions altered subcellular metals partitioning. - Abstract: Interactions of Cu, Cd and Zn were studied at the subcellular level in juvenile rainbow trout (Oncorhynchus mykiss) fed diets containing (μg/g) 500 Cu, 1000 Zn and 500 Cd singly and as a ternary mixture for 28 days. Livers were harvested and submitted to differential centrifugation to isolate components of metabolically active metal pool (MAP: heat-denaturable proteins (HDP), organelles, nuclei) and metabolically detoxified metal pool (MDP: heat stable proteins (HSP), NaOH-resistant granules). Results indicated that Cd accumulation was enhanced in all the subcellular compartments, albeit at different time points, in fish exposed to the metals mixture relative to those exposed to Cd alone, whereas Cu alone exposure increased Cd partitioning. Exposure to the metals mixture reduced (HDP) and enhanced (HSP, nuclei and granules) Cu accumulation while exposure to Zn alone enhanced Cu concentration in all the fractions analyzed without altering proportional distribution in MAP and MDP. Although subcellular Zn accumulation was less pronounced than that of either Cu or Cd, concentrations of Zn were enhanced in HDP, nuclei and granules from fish exposed to the metals mixture relative to those exposed to Zn alone. Cadmium alone exposure mobilized Zn and Cu from the nuclei and increased Zn accumulation in organelles and Cu in granules, while Cu alone exposure stimulated Zn accumulation in HSP, HDP and organelles. Interestingly, Cd alone exposure increased the partitioning of the three metals in MDP indicative of enhanced detoxification. Generally the accumulated metals were predominantly metabolically active: Cd, 67–83%; Cu, 68–79% and Zn, 60–76

  7. Bioaccumulation of silver nanoparticles in rainbow trout (Oncorhynchus mykiss): Influence of concentration and salinity

    Energy Technology Data Exchange (ETDEWEB)

    Salari Joo, Hamid, E-mail: h.salary1365@gmail.com [Department of Aquaculture, Marine Science Faculty, Tarbiat Modares University, Mazandaran, Noor (Iran, Islamic Republic of); Kalbassi, Mohammad Reza, E-mail: kalbassi_m@modares.ac.ir [Department of Aquaculture, Marine Science Faculty, Tarbiat Modares University, Mazandaran, Noor (Iran, Islamic Republic of); Yu, Il Je, E-mail: u1670916@chol.com [Institute of Nano-product Safety Research, Hoseo University, 165 Sechul-ri, Baebang-myun, Asan 336-795 (Korea, Republic of); Lee, Ji Hyun, E-mail: toxin@dreamwiz.com [Institute of Nano-product Safety Research, Hoseo University, Asan (Korea, Republic of); Johari, Seyed Ali, E-mail: a.johari@uok.ac.ir [Aquaculture Department, Natural Resources Faculty, University of Kurdistan, Kurdistan, Sanandaj (Iran, Islamic Republic of)

    2013-09-15

    Highlights: •We studied influence of concentration and salinity on bioaccumulation of silver nanoparticles in rainbow trout (Oncorhynchus mykiss). •The Ag-NPs were characterized using standard methods. •The organisms were exposed to Ag-NPs in three different salinity concentrations, for 14 days in static renewal systems. •The bioaccumulation of Ag in the studied tissues was concentration-dependent in all the salinities and its order were liver > kidneys ≈ gills > white muscles respectively. -- Abstract: With the increasing use of silver nanoparticles (Ag-NPs), their entrance into aquatic ecosystems is inevitable. Thus, the present study simulated the potential fate, toxicity, and bioaccumulation of Ag-NPs released into aquatic systems with different salinities. The Ag-NPs were characterized using inductively coupled plasma-atomic emission spectroscopy (ICP-AES), dynamic light scattering (DLS), transmission electron microscopy (TEM), energy-dispersive X-ray analysis (EDX), and UV–vis spectroscopy. Juvenile rainbow trout were exposed to Ag-NPs in three different salinity concentrations, including low (0.4 ppt), moderate (6 ± 0.3 ppt), and high (12 ± 0.2 ppt) salinity, for 14 days in static renewal systems. The nominal Ag-NP concentrations in the low salinity were 0.032, 0.1, 0.32, and 1 ppm, while the Ag-NP concentrations in the moderate and high salinity were 3.2, 10, 32, and 100 ppm. UV–vis spectroscopy was used during 48 h (re-dosing time) to evaluate the stability and possible changes in size of the Ag-NPs in the water. The results revealed that the λ{sub max} of the Ag-NPs remained stable (415–420 nm) at all concentrations in the low salinity with a reduction of absorbance between 380 and 550 nm. In contrast, the λ{sub max} quickly shifted to a longer wavelength and reduced absorbance in the moderate and higher salinity. The bioaccumulation of Ag in the studied tissues was concentration-dependent in all the salinities based on the following

  8. Subcellular interactions of dietary cadmium, copper and zinc in rainbow trout (Oncorhynchus mykiss)

    Energy Technology Data Exchange (ETDEWEB)

    Kamunde, Collins, E-mail: ckamunde@upei.ca [Department of Biomedical Sciences, Atlantic Veterinary College, University of Prince Edward Island, 550 University Avenue, Charlottetown, PE, C1A 4P3 (Canada); MacPhail, Ruth [Department of Biomedical Sciences, Atlantic Veterinary College, University of Prince Edward Island, 550 University Avenue, Charlottetown, PE, C1A 4P3 (Canada)

    2011-10-15

    Highlights: Interactions of Cu, Cd and Zn were studied at the subcellular level in rainbow trout. Metals accumulated in the liver were predominantly metabolically active. Cd, Cu and Zn exhibited both competitive and cooperative interactions. The metal-metal interactions altered subcellular metals partitioning. - Abstract: Interactions of Cu, Cd and Zn were studied at the subcellular level in juvenile rainbow trout (Oncorhynchus mykiss) fed diets containing ({mu}g/g) 500 Cu, 1000 Zn and 500 Cd singly and as a ternary mixture for 28 days. Livers were harvested and submitted to differential centrifugation to isolate components of metabolically active metal pool (MAP: heat-denaturable proteins (HDP), organelles, nuclei) and metabolically detoxified metal pool (MDP: heat stable proteins (HSP), NaOH-resistant granules). Results indicated that Cd accumulation was enhanced in all the subcellular compartments, albeit at different time points, in fish exposed to the metals mixture relative to those exposed to Cd alone, whereas Cu alone exposure increased Cd partitioning. Exposure to the metals mixture reduced (HDP) and enhanced (HSP, nuclei and granules) Cu accumulation while exposure to Zn alone enhanced Cu concentration in all the fractions analyzed without altering proportional distribution in MAP and MDP. Although subcellular Zn accumulation was less pronounced than that of either Cu or Cd, concentrations of Zn were enhanced in HDP, nuclei and granules from fish exposed to the metals mixture relative to those exposed to Zn alone. Cadmium alone exposure mobilized Zn and Cu from the nuclei and increased Zn accumulation in organelles and Cu in granules, while Cu alone exposure stimulated Zn accumulation in HSP, HDP and organelles. Interestingly, Cd alone exposure increased the partitioning of the three metals in MDP indicative of enhanced detoxification. Generally the accumulated metals were predominantly metabolically active: Cd, 67-83%; Cu, 68-79% and Zn, 60-76%. Taken

  9. Comparison of chemical, microbiological and histological changes in fresh, frozen and double frozen rainbow trout (Oncorhynchus mykiss

    Directory of Open Access Journals (Sweden)

    Peter Popelka

    2014-01-01

    Full Text Available The final quality of fish meat depends on the chemical and microbiological quality of fish at the time of freezing as well as on other factors including storage temperature and freezing rate. Analysis of chemical composition (water, protein and fat content, expressible drip, total volatile nitrogen levels, microbiological analyses (total viable counts, Enterobacteriaceae, psychrotrophic bacteria and histological examinations on dorsal skeletal muscles were carried out to distinguish fresh, frozen and double frozen rainbow trout (Oncorhynchus mykiss. Significantly higher expressible drip and total volatile base nitrogen concentrations (P Enterobacteriaceae and psychrotrophic bacteria were determined in double frozen trout. The light microscopy of fresh trout muscles did not show any microstructural changes, whereas deformations of muscle fibres and optically empty areas were found in frozen trout. Remarkable defects of the muscle structure in double frozen trout were demonstrated and total disruption of muscle fibres was found. The freezing of trout resulted in various structural changes in the dorsal skeletal musculature. This is a first study comparing changes in fresh, frozen and repeatedly frozen trout. Chemical, microbiological and subsequent histological examinations can be used for revealing the foul practices confusing the consumer with offering thawed fish instead of fresh cooled fish.

  10. Heavy metal content in the meat of common carp (Cyprinuscarpio L.and rainbow trout (Oncorhynchus mykiss W., cultivated under different technologies

    Directory of Open Access Journals (Sweden)

    St. Stoyanova

    2016-03-01

    Full Text Available Abstract. Water pollution from industrial production and developing agriculture is a serious problem in aquaculture. The aim of this study was to determine the content of heavy metals Zn (zink, Pb(lead, Ni (nickel and Cd (cadmium in the muscles of common carp (Cyprinus carpio L. and rainbow trout (Oncorhynchus mykiss W., grown under different technologies. In the current study were investigated common carp (Cyprinus carpio and rainbow trout (Oncorhynchus mykiss, cultivated in net cages, earthen ponds and raceways. The concentration of heavy metals in the muscles of fish was determined by the methods of AAS in the Scientific laboratory of the Faculty of Agriculture. The influence of different production technologies on the bioaccumulation of Zn, Pb, Ni and Cd (in the flesh of common carp and rainbow trout was found. The Ni content in muscles was 31.25% higher in common carp, cultured at earthen ponds, compared with its content in the flesh of the fish raised in net cages. The concentration of Pd and Ni in rainbow trout, raised in raceways was higher than that determinated for rainbow trout cultivated in net cages, by 25.0% and 7.14%, respectively. The concentration of Cd and Zn of these species, grown in raceways were lower by 33.33% and 2.14%, respectively, compared with their concentration in rainbow trout, cultivated in net cages.

  11. Apoptosis of gut-associated lymphoid tissue in rainbow trout Oncorhynchus mykiss after incubation with Candida albicans and bacterial lipopolysaccharide.

    Science.gov (United States)

    Passantino, L; Ostillio, A; Cianciotta, A; Russo, C; Carrassi, M; Patruno, R; Dhaskali, L; Passantino, G F; Passantino, A

    2011-06-01

    Until now a few studies have been carried out on the gut lymphoid system in fish despite its protective role in the host. Here, we have evaluated the effects of Candida albicans (Ca) and lipopolysaccaride (LPS) on the pyloric and terminal segments of gut in the rainbow trout Oncorhynchus mykiss. In particular, data show that both Ca and LPS are able to cause apoptosis of intestinal lymphoid cells as detected by the terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL) procedure. These findings suggest a further modality of gut response in fish to environmental antigens.

  12. Micronuclei frequency in circulating erythrocytes from rainbow trout (Oncorhynchus mykiss) subjected to radiation, an image analysis and flow cytometric study

    International Nuclear Information System (INIS)

    Schultz, N.; Norrgren, L.; Grawe, J.; Johannisson, A.; Medhage, O.

    1993-01-01

    Rainbow trout (oncorhynchus mykiss) were exposed to a single X-ray dose of 4 Gy. The frequency of micronuclei in the peripheral erythrocytes was investigated at regular intervals up to 58 days after the exposure. A flow cytometric method and a semi-automatic image analysis method were used to estimate the micronuclei frequency. The results show that both methods can detect an increased frequency of micronuclei in peripheral erythrocytes from exposed fish. However, the semi-automatic image analysis method was the most stable and sensitive. (Author)

  13. Organically bound tritium (OBT) formation in rainbow trout (Oncorhynchus mykiss): HTO and OBT-spiked food exposure experiments

    International Nuclear Information System (INIS)

    Kim, S.B.; Shultz, C.; Stuart, M.; McNamara, E.; Festarini, A.; Bureau, D.P.

    2013-01-01

    In order to determine the rate of organically bound tritium (OBT) formation, rainbow trout (Oncorhynchus mykiss) were exposed to tritiated water (HTO) or OBT-spiked food. The HTO (in water) exposure study was conducted using a tritium activity concentration of approximately 7000 Bq/L and the OBT (in food) exposure study was conducted using a tritium activity concentration of approximately 30,000 Bq/L. Fish in both studies were expected to be exposed to similar tritium levels assuming 25% incorporation of the tritiated amino acids found in the food. Four different sampling campaigns of HTO exposure (Day 10, 30, 70, 140) and five different sampling campaigns of OBT-spiked food exposure (Day 9, 30, 70, 100, 140) were conducted to measure HTO and OBT activity concentrations in fish tissues. OBT depuration was also evaluated over a period of 30 days following the 140 d exposure studies. The results suggested that the OBT formation rate was slower when the fish were exposed to HTO compared to when the fish were ingesting OBT. In addition, the results indicated that OBT can bioaccumulate in fish tissues following OBT-spiked food exposure. - Highlights: ► The rate of organically bound tritium (OBT) formation was determined in rainbow trout. ► Rainbow trout were exposed to tritium in the form of tritiated water (HTO) and OBT-spiked food. ► OBT formation rate was slower when the fish were exposed to HTO compared to when the fish were ingesting OBT.

  14. Replication of Infectious Pancreatic Necrosis Virus in Different Cell Lines and in Rainbow Trout (Oncorhynchus Mykiss Fingerlings

    Directory of Open Access Journals (Sweden)

    Matvienko Natalija

    2014-07-01

    Full Text Available The results of a study of Infectious Pancreatic Necrosis Virus (IPNV isolated in natural reservoirs in Ukraine are presented. The pathogenicity of isolates was investigated in vitro on cell cultures and in vivo on rainbow trout, Oncorhynchus mykiss (Walbaum, fingerlings. Experimental indications were that the Ukrainian IPNV isolates have affinity with reference European strains. During the reproduction of these isolates in cell cultures of FHM (fat head minnow, RTG-2 (rainbow trout gonads, and BF-2 (bluegill caudal peduncle, complicated degenerative changes were visible that finally led to the full destruction of cell monolayers. The experimental infection of rainbow trout fingerlings resulted in typical disease symptoms that were systemic. However, obvious evidence of viral infection was noted in single individuals only, and the majority of experimental fish died without visible disease symptoms. During the study of physicochemical properties, it was noted that Ukrainian isolates completely lost their infectivity with chloroform treatment and heating to 60°C. This proved that IPNV isolates are resistant to Ion concentrations in the range of pH 3.0 to 12.0.

  15. The effect of bifenthrin on the dopaminergic pathway in juvenile rainbow trout (Oncorhynchus mykiss).

    Science.gov (United States)

    Crago, Jordan; Schlenk, Daniel

    2015-05-01

    Bifenthrin is a type I pyrethroid pesticide, which has been shown to increase plasma estrogen concentrations in several fish models. The mechanism of action by which bifenthrin alters 17β-estradiol (E2) is unclear. E2 biosynthesis is regulated through pituitary follicle stimulating hormone, which is directly controlled by hypothalamic gonadotropin releasing hormone (GnRH2). Since dopaminergic signaling significantly influences GnRH2 release in fish, the goal of the study was to determine the effect of a 96 h and 2 weeks exposure to bifenthrin on dopaminergic signaling in juvenile rainbow trout (Oncorhynchus mykiss) (RT). Our results indicated that a decrease in dopamine receptor 2A (DR2A) expression was associated with a trend toward an increase in plasma E2 following exposure at 96 h and 2 weeks, and a significant increase in the relative expression of vitellogenin mRNA at 2 weeks. DR2A mRNA expression decreased 426-fold at 96 h and 269-fold at 2 weeks in the brains of 1.5 ppb (3.55 pM) bifenthrin treated RT. There was an increase in tyrosine hydroxylase transcript levels at 96 h, which is indicative of dopamine production in the brains of the 1.5 ppb (3.55 pM) bifenthrin treated RT. A significant increase in the relative expression of GnRH2 was observed at 96 h but a significant decrease was noted after 2 weeks exposure indicating potential feedback loop activation. These results indicate that the estrogenic-effects of bifenthrin may result in part from changes in signaling within the dopaminergic pathway, but that other feedback pathways may also be involved. Copyright © 2015 Elsevier B.V. All rights reserved.

  16. Distribution of T Cells in Rainbow Trout (Oncorhynchus mykiss) Skin and Responsiveness to Viral Infection

    Science.gov (United States)

    Leal, Esther; Granja, Aitor G.; Zarza, Carlos; Tafalla, Carolina

    2016-01-01

    Although the skin constitutes the first line of defense against waterborne pathogens, there is a great lack of information regarding the skin associated lymphoid tissue (SALT) and whether immune components of the skin are homogeneously distributed through the surface of the fish is still unknown. In the current work, we have analyzed the transcription of several immune genes throughout different rainbow trout (Oncorhynchus mykiss) skin areas. We found that immunoglobulin and chemokine gene transcription levels were higher in a skin area close to the gills. Furthermore, this skin area as well as other anterior sections also transcribed significantly higher levels of many different immune genes related to T cell immunity such as T cell receptor α (TCRα), TCRγ, CD3, CD4, CD8, perforin, GATA3, Tbet, FoxP3, interferon γ (IFNγ), CD40L and Eomes in comparison to posterior skin sections. In agreement with these results, immunohistochemical analysis revealed that anterior skin areas had a higher concentration of CD3+ T cells and flow cytometry analysis confirmed that the percentage of CD8+ T lymphocytes was also higher in anterior skin sections. These results demonstrate for the first time that T cells are not homogeneously distributed throughout the teleost skin. Additionally, we studied the transcriptional regulation of these and additional T cell markers in response to a bath infection with viral hemorrhagic septicemia virus (VHSV). We found that VHSV regulated the transcription of several of these T cell markers in both the skin and the spleen; with some differences between anterior and posterior skin sections. Altogether, our results point to skin T cells as major players of teleost skin immunity in response to waterborne viral infections. PMID:26808410

  17. The effect of chlorpyrifos on salinity acclimation of juvenile rainbow trout (Oncorhynchus mykiss).

    Science.gov (United States)

    Amiri, Bagher Mojazi; Xu, Elvis Genbo; Kupsco, Allison; Giroux, Marissa; Hoseinzadeh, Mahbubeh; Schlenk, Daniel

    2018-02-01

    As a part of their unique life cycle, most salmonids undergo a transition from fresh water to salt water requiring various adjustments in metabolism, osmoregulation and ion regulation. Exposure to pesticides may affect the acclimation of juvenile salmonids to salt water during downstream migration to estuaries. Using the Caspian Sea as a model waterbody, the present study aimed to determine how the toxicity of the organophosphate pesticide chlorpyrifos (CPF) impacts saline acclimation of rainbow trout (Oncorhynchus mykiss). We pre-exposed 4-month-old fish to nominal concentrations of 0, 20, 40, 80, 160 μg/L of CPF for seven days, and then gradually to salinity (12 ppt) for another seven days. Mortality, levels of cortisol, T3 and T4 in serum, and expression of genes involved in gill ion transport (Na + /K + ATPase α1a and α1b) and liver xenobiotic detoxification (Glutathione-S-Transferase pi, GST) were measured at day fourteen. Cortisol concentrations in serum were not changed by CPF exposure in freshwater, but serum T3 increased up to three fold relative to controls in freshwater. Following salinity acclimation, T3 and T4 concentrations in the serum were both increased up to 2.5 and 8.8 fold in animals treated with CPF followed by saltwater. Na+/K + ATPase α1a and α1b mRNA in gill were unchanged by CPF treatment in freshwater but trended higher in CPF-treated animals after salinity acclimation. Hepatic mRNA of GST was significantly increased following exposure to CPF but was unchanged after saltwater exposure. Although saltwater treatment reduced the acute lethality of CPF, changes in T3/T4 suggest sublethal impacts may occur in CPF-treated fish after they acclimate to Caspian seawater. Copyright © 2017 Elsevier B.V. All rights reserved.

  18. Fish production and some traits of meat quality in rainbow trout (Oncorhynchus mykiss farmed in different production systems

    Directory of Open Access Journals (Sweden)

    St. Stoyanova

    2016-12-01

    Full Text Available Abstract. The rainbow trout (Oncorhynchus mykiss, an important species in Bulgarian aquaculture, is farmed in different production systems as raceways, net cages etc. The aim of the present study was to evaluate the effect of two different rearing systems on fish production, survival rate, meat chemical, mineral composition and farming economic efficiency of culticated rainbow trout (Oncorhynchus mykiss. The information from a survey on fish production and economic efficiency traits was collected from two national rainbow trout farms using the two commonest fish farming systems: in raceways, Happy Fish Ltd fish farm and in net cages, Forest Group Ltd fish farm. The average individual weight gain (g, total weight gain (kg, feed conversion ratio, production costs of 1 kg fish and the economic efficiency coefficients were determined for the two studied fish farms. The final live weight of rainbow trout in net cages was 0.30 kg vs 0.35 kg in raceways. The average individual weight gain was higher in raceways farming system (0.30 kg than in net cages farm (0.26 kg. The mortality rate of fish in raceways was considerably lower: only 1% as compared to that in net cages (4%. The feed conversion ratio at the end of the experiment showed identical values for trout in both farms 1.01. The meat water content of fish reared in raceways and net cages was 77.46±0.65% and 74.52±0.52% respectively (P≤0.01.The protein content of fish meat was higher in fish farmed in net cages 18.84±0.29% as compared to fish cultivated in raceways 17.60±0.49% (P 0.05. Meat fat content of rainbow trout, reared in the net cage system was also considerably higher (5.26±0.30% than the respective parameter in fish farmed in ponds (3.60±0.15% (P≤0.001. The content of Ca and P was higher in rainbow trouts reared in raceways (138.96±1.12 mg.kg and 2844.32±39.31 mg.kg 1 -1 -1 compared with the values of these parameters of fish in net cages (134.46±1.96 mg.kg and 2690.31±42

  19. Are brown trout Salmo trutta fario and rainbow trout Oncorhynchus mykiss two of a kind? A comparative study of salmonids to temperature-influenced Tetracapsuloides bryosalmonae infection.

    Science.gov (United States)

    Bailey, C; Schmidt-Posthaus, H; Segner, H; Wahli, T; Strepparava, N

    2018-02-01

    Proliferative kidney disease (PKD) of salmonids caused by Tetracapsuloides bryosalmonae causes high mortalities of wild brown trout (Salmo trutta fario) and farmed rainbow trout (Oncorhynchus mykiss) at elevated water temperatures. Here the aim was to compare the temperature-dependent modulation of T. bryosalmonae in the two salmonid host species, which display different temperature optima. We used a novel experimental set-up in which we exposed brown trout and rainbow trout to an identical quantified low concentration of T. bryosalmonae for a short time period (1 hr). We followed the development of the parasite in the fish hosts for 70 days. PKD prevalence and parasite kinetics were assessed using qPCR. Exposures were performed at temperatures (12°C and 15°C) that reflect an environmental scenario that may occur in the natural habitat of salmonids. T. bryosalmonae infection was confirmed earliest in brown trout kept at 15°C (day 7 post-exposure) while, in all other groups, T. bryosalmonae was not confirmed until day 15 post-exposure. Moreover, significantly greater infection prevalence and a faster increase of parasite intensity were observed in brown trout kept at 15°C than in all other groups. These results indicate that PKD is differentially modulated by water temperature in related host species. © 2017 John Wiley & Sons Ltd.

  20. Isolation and Functional Characterisation of a fads2 in Rainbow Trout (Oncorhynchus mykiss with Δ5 Desaturase Activity.

    Directory of Open Access Journals (Sweden)

    Noor Khalidah Abdul Hamid

    Full Text Available Rainbow trout, Oncorhynchus mykiss, are intensively cultured globally. Understanding their requirement for long-chain polyunsaturated fatty acids (LC-PUFA and the biochemistry of the enzymes and biosynthetic pathways required for fatty acid synthesis is important and highly relevant in current aquaculture. Most gnathostome vertebrates have two fatty acid desaturase (fads genes with known functions in LC-PUFA biosynthesis and termed fads1 and fads2. However, teleost fish have exclusively fads2 genes. In rainbow trout, a fads2 cDNA had been previously cloned and found to encode an enzyme with Δ6 desaturase activity. In the present study, a second fads2 cDNA was cloned from the liver of rainbow trout and termed fads2b. The full-length mRNA contained 1578 nucleotides with an open reading frame of 1365 nucleotides that encoded a 454 amino acid protein with a predicted molecular weight of 52.48 kDa. The predicted Fads2b protein had the characteristic traits of the microsomal Fads family, including an N-terminal cytochrome b5 domain containing the heme-binding motif (HPPG, histidine boxes (HDXGH, HFQHH and QIEHH and three transmembrane regions. The fads2b was expressed predominantly in the brain, liver, intestine and pyloric caeca. Expression of the fasd2b in yeast generated a protein that was found to specifically convert eicosatetraenoic acid (20:4n-3 to eicosapentaenoic acid (20:5n-3, and therefore functioned as a Δ5 desaturase. Therefore, rainbow trout have two fads2 genes that encode proteins with Δ5 and Δ6 desaturase activities, respectively, which enable this species to perform all the desaturation steps required for the biosynthesis of LC-PUFA from C18 precursors.

  1. Isolation and Functional Characterisation of a fads2 in Rainbow Trout (Oncorhynchus mykiss) with Δ5 Desaturase Activity

    Science.gov (United States)

    Abdul Hamid, Noor Khalidah; Carmona-Antoñanzas, Greta; Monroig, Óscar; Tocher, Douglas R.; Turchini, Giovanni M.; Donald, John A.

    2016-01-01

    Rainbow trout, Oncorhynchus mykiss, are intensively cultured globally. Understanding their requirement for long-chain polyunsaturated fatty acids (LC-PUFA) and the biochemistry of the enzymes and biosynthetic pathways required for fatty acid synthesis is important and highly relevant in current aquaculture. Most gnathostome vertebrates have two fatty acid desaturase (fads) genes with known functions in LC-PUFA biosynthesis and termed fads1 and fads2. However, teleost fish have exclusively fads2 genes. In rainbow trout, a fads2 cDNA had been previously cloned and found to encode an enzyme with Δ6 desaturase activity. In the present study, a second fads2 cDNA was cloned from the liver of rainbow trout and termed fads2b. The full-length mRNA contained 1578 nucleotides with an open reading frame of 1365 nucleotides that encoded a 454 amino acid protein with a predicted molecular weight of 52.48 kDa. The predicted Fads2b protein had the characteristic traits of the microsomal Fads family, including an N-terminal cytochrome b5 domain containing the heme-binding motif (HPPG), histidine boxes (HDXGH, HFQHH and QIEHH) and three transmembrane regions. The fads2b was expressed predominantly in the brain, liver, intestine and pyloric caeca. Expression of the fasd2b in yeast generated a protein that was found to specifically convert eicosatetraenoic acid (20:4n-3) to eicosapentaenoic acid (20:5n-3), and therefore functioned as a Δ5 desaturase. Therefore, rainbow trout have two fads2 genes that encode proteins with Δ5 and Δ6 desaturase activities, respectively, which enable this species to perform all the desaturation steps required for the biosynthesis of LC-PUFA from C18 precursors. PMID:26943160

  2. Photobacterium damselae subsp damselae, an emerging pathogen in Danish rainbow trout, Oncorhynchus mykiss (Walbaum), mariculture

    DEFF Research Database (Denmark)

    Pedersen, Karl; Skall, Helle Frank; Lassen-Nielsen, Anne Marie

    2009-01-01

    A selection of 16 field isolates of Photobacterium damselae from marine rainbow trout farms in Denmark was subjected to phenotypic and genotypic characterization and pathogenicity to fish. All isolates belonged to the subspecies damselae, being positive for haemolysis, motility and urease...

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

    DEFF Research Database (Denmark)

    Hauge, Helena; Vendramin, Niccolò; Taksdal, Torunn

    2017-01-01

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

  4. Toxicity of quantum dots and cadmium to rainbow trout (Oncorhynchus mykiss in early ontogenesis

    Directory of Open Access Journals (Sweden)

    Živilė Cibulskaitė

    2015-11-01

    Full Text Available The aim of the study was to investigate toxic effects of CdSe/ZnS-COOH quantum dots (QD and cadmium (Cd on biological parameters of rainbow trout (Oncorhychus mykiss in its early stages of development (embryos and larvae. It was found that short-term (24-, 96-hour exposure to sublethal concentrations of QD and Cd increased mortality of embryos and larvae, disturbed function of the cardio-respiratory system (gill ventilation frequency, heart rate and affected behavioural responses (individuals making nests in rainbow trout larvae. The results indicated that toxic effects of QD and Cd on rainbow trout larvae depended on the type of chemical substance, affected stage of development and exposure duration. Comparative studies of the effects of QD and Cd on rainbow trout in early stages of development showed that larvae were more sensitive to Cd and QD as compared to embryos. It was suggested that the chorion envelopes of eggs surround and protect the embryo from QD and Cd. Cadmium was more toxic to larvae than QD. Longer exposure (96-hour of QD and Cd induced more remarkable changes in test-parameters. This original study requires more investigations evaluating the mechanism of toxicity of QD to fish.

  5. Toxicokinetics of the neonicotinoid insecticide imidacloprid in rainbow trout (Oncorhynchus mykiss)

    Science.gov (United States)

    Imidacloprid (IMI) is the largest selling insecticide internationally. Little is known about the toxicokinetics of IMI in fish, however. In vivo time-course studies were conducted to study the distribution and elimination of IMI in rainbow trout. Animals confined to respiromet...

  6. Abiotic variables accounting for presence of the exotic rainbow trout (Oncorhynchus mykiss in Eastern Quebec Rivers

    Directory of Open Access Journals (Sweden)

    Thibault I.

    2010-10-01

    Full Text Available Rainbow trout is an exotic fish species that has been introduced in Quebec (Canada since 1893–1894. Despite spatially-restricted stocking for recreational fishing, the species has spread throughout the Saint Lawrence River. In this study, the relationship between rainbow trout occurrence (presence or absence and abiotic variables (river geomorphology and climate was examined for 91 coastal rivers throughout Eastern Quebec in order to determine which variables promote or impede the ongoing invasion process. Results revealed that rainbow trout presence in Eastern Quebec was primarily determined by geomorphological parameters. The invader’s presence was strongly related to the presence of tributaries (especially larger ones. To a lesser extent, the presence of rainbow trout was positively related to warm spring and summer temperatures and negatively related to the peak flood date occurring during the egg deposition period (May. This study proposes a parsimonious modelling approach to identify which environmental parameters favour the spreading of an invader, even when a limited dataset is available due to the incomplete invasion process.

  7. Individual condition and stream temperature influences early maturation of rainbow and steelhead trout, Oncorhynchus mykiss

    Science.gov (United States)

    John R. McMillan; Jason B. Dunham; Gordon H. Reeves; Justin S. Mills; Chris E. Jordan

    2012-01-01

    Alternative male phenotypes in salmonine fishes arise from individuals that mature as larger and older anadromous marine-migrants or as smaller and younger freshwater residents. To better understand the processes influencing the expression of these phenotypes we examined the influences of growth in length (fork length) and whole body lipid content in rainbow trout (...

  8. Family differences related to carbohydrate utilization in rainbow trout Oncorhynchus mykiss

    Science.gov (United States)

    Rainbow trout utilize protein as an energy source much more efficiently than carbohydrates. Alternative diets utilizing plant material typically contain higher levels of carbohydrate than standard fish meal diets. The goal of this study was to determine if there are molecular and physiological diffe...

  9. Survival of Flavobacterium psychrophilum in rainbow trout ( Oncorhynchus mykiss ) serum in vitro

    DEFF Research Database (Denmark)

    Wiklund, T.; Dalsgaard, Inger

    2002-01-01

    Virulent and non-virulent strains of Flavobacterium psychrophilum of different serotypes were examined for survival and growth in non-immune and immune rainbow trout serum, in vitro. A majority of the examined strains consumed complement of non-immune serum, but the complement cascade was not able...

  10. BIOACCUMULATION AND BIOTRANSFORMATION OF CHIRAL TRIAZOLE FUNGICIDES IN RAINBOW TROUT (ONCORHYNCHUS MYKISS)

    Science.gov (United States)

    There are very little data on the bioaccumulation and biotransformation of current-use pesticides (CUPs) despite the fact that such data are critical in assessing their fate and potential toxic effects in aquatic organisms. To help address this issue, juvenile rainbow trout (Onco...

  11. The effects of ozonation on performance, health and welfare of rainbow trout Oncorhynchus mykiss in low-exchange water recirculation aquaculture systems

    Science.gov (United States)

    A controlled four-month trial was conducted to compare the effects of ozonation (oxidation-reduction potential setpoint = 250 mV) versus no ozonation on rainbow trout Oncorhynchus mykiss performance, health, and welfare in replicated WRAS operated at low exchange rates (0.26% of the total recirculat...

  12. The effects of ozone and water exchange rates on water quality and rainbow trout Oncorhynchus mykiss performance in replicated water recirculating systems

    Science.gov (United States)

    Rainbow trout Oncorhynchus mykiss performance and water quality were evaluated and compared within six replicated 9.5 cubic meter water recirculating aquaculture systems (WRAS) operated with and without ozone at various water exchange rates. Three separate studies were conducted: 1) low water exchan...

  13. Flavobacterium branchiophilum and F. succinicans associated with bacterial gill disease in rainbow trout Oncorhynchus mykiss (Walbaum) in water recirculation aquaculture systems

    Science.gov (United States)

    Raised rainbow trout Oncorhynchus mykiss in six replicated water recirculation aquaculture systems (WRAS), and manipulated environmental conditions to promote bacterial gill disease (BGD). For each episode of BGD, gill tissue was sampling from affected fish, unaffected fish within the same WRAS, and...

  14. Comparing the effects of high vs. low nitrate on the health, performance, and welfare of juvenile rainbow trout Oncorhynchus mykiss within water recirculating aquaculture systems

    Science.gov (United States)

    Previous research indicates that rainbow trout (Oncorhynchus mykiss) begin to exhibit health and welfare problems when cultured within water recirculating aquaculture systems (WRAS) operated at low exchange (6.7 days hydraulic retention time) and a mean feed loading rate of 4.1 kg feed/m3 daily make...

  15. A major allergen in rainbow trout (Oncorhynchus mykiss): complete sequences of parvalbumin by MALDI tandem mass spectrometry.

    Science.gov (United States)

    Aiello, Donatella; Materazzi, Stefano; Risoluti, Roberta; Thangavel, Hariprasad; Di Donna, Leonardo; Mazzotti, Fabio; Casadonte, Francesca; Siciliano, Carlo; Sindona, Giovanni; Napoli, Anna

    2015-08-01

    Fish parvalbumin (PRVB) is an abundant and stable protein in fish meat. The variation in cross-reactivity among individuals is well known and explained by a broad repertoire of molecular forms and differences between IgE-binding epitopes in fish species. PVRB has "sequential" epitopes, which retain their IgE-binding capacity and allergenicity also after heating and digestion using proteolytic enzymes. From the allergonomics perspective, PRVB is still a challenging target due to its multiple isoforms present at different degrees of distribution. Little information is available in the databases about PVRBs from Oncorhynchus mykiss. At present, only two validated, incomplete isoforms of this species are included in the protein databases: parvalbumin beta 1 (P86431) and parvalbumin beta 2 (P86432). A simple and rapid protocol has been developed for selective solubilization of PRVB from the muscle of farmed rainbow trout (Oncorhynchus mykiss), followed by calcium depletion, proteolytic digestion, MALDI MS, and MS/MS analysis. With this strategy thermal allergen release was assessed and PRVB1 (P86431), PRVB1.1, PRVB2 (P86432) and PRVB2.1 variants from the rainbow trout were sequenced. The correct ordering of peptide sequences was aided by mapping the overlapping enzymatic digests. The deduced peptide sequences were arranged and the theoretical molecular masses (Mr) of the resulting sequences were calculated. Experimental masses (Mr) of each PRVB variant were measured by linear MALDI-TOF.

  16. Phylogenetic relationships of Iranian infectious hematopoietic necrosis virus of rainbow trout (Oncorhynchus mykiss) based on the glycoprotein gene

    Science.gov (United States)

    Adel, Milad; Amiri, Alireza Babaalian; Dada, Maryam; Kurath, Gael; Laktarashi, Bahram; Ghajari, Amrolah; Breyta, Rachel

    2016-01-01

    Infectious hematopoietic necrosis virus (IHNV), a member of family Rhabdoviridae and genus Novirhabdoviridae, causes a highly lethal disease of salmon and trout. In Iran IHNV was first detected in 2001 on farms rearing rainbow trout (Oncorhynchus mykiss). To evaluate the genetic relationships of IHNV from northern and western Iran, the sequences of a 651-nt region of the glycoprotein gene were determined for two Iranian isolates. These sequences were analyzed to evaluate their genetic relatedness to worldwide isolates representing the five known genogroups of IHNV. Iranian isolates were most closely related to European isolates within the genogroup E rather than those of North American genogroups U, M and L, or the Asian genogroup J. It appears that Iranian IHNV was most likely introduced to Iran from a source in Europe by the movement of contaminated fish eggs.

  17. Efficacy of emamectin benzoate in the control of Argulus coregoni (Crustacea: Branchiura) on rainbow trout Oncorhynchus mykiss.

    Science.gov (United States)

    Hakalahti, T; Lankinen, Y; Valtonen, E T

    2004-09-08

    Efficacy of in-feed treatment with emamectin benzoate (Slice) for the control of ectoparasitic Argulus coregoni on rainbow trout Oncorhynchus mykiss was tested under laboratory and field conditions. In both experiments fish were fed with fish feed to deliver a therapeutic dose of 0 (control) or 50 microg emamectin benzoate kg(-1) d(-1) (treatment) for a period of 7 d. After 3 d of challenge with A. coregoni in the laboratory, the infestation level in treated fish was lower than that observed in the controls (p 20. The prevalence of A. coregoni remained emamectin benzoate concentration in fish remained at a level high enough to kill A. coregoni over a period of 9 wk. Emamectin benzoate was very effective in the control of A. coregoni infesting trout.

  18. Chronic effect of waterborne colloidal silver nanoparticles on plasma biochemistry and hematology of rainbow trout (Oncorhynchus mykiss

    Directory of Open Access Journals (Sweden)

    Seyed Ali Johari

    2016-05-01

    Full Text Available Objective: To investigate the possible effects of silver nanoparticles (AgNPs on some blood and plasma indices of rainbow trout (Oncorhynchus mykiss. Methods: Hence, fish were exposed for 21 days to sub-lethal concentrations of colloidal AgNPs and blood parameters including erythrocyte size and hematocrit, plasma parameters including cholinesterase, cortisol, sodium, chloride, and potassium, and also silver concentration in plasma were measured following the 11th and 21st days of exposure. Results: According to the results of present study, higher concentrations of AgNPs had more significant effects on plasma biochemistry and hematology of trout. The greatest impacts were decline of chloride ions and increase of cortisol and cholinesterase. Also fish exposed to AgNPs significantly increased silver concentration in the plasma. Conclusions: Further studies are needed to identify appropriate blood biomarkers following fish exposed to nanomaterials, especially AgNPs.

  19. Effects of carbon dioxide exposure on intensively cultured rainbow trout Oncorhynchus mykiss: Physiological responses and fillet attributes

    Science.gov (United States)

    Danley, M.L.; Kenney, P.B.; Mazik, P.M.; Kiser, R.; Hankins, J.A.

    2005-01-01

    Rainbow trout Oncorhynchus mykiss (261.6 ?? 24.7 g initial weight, mean ?? SEM) at 13.1 ?? 0.2 C were exposed for 94 d to one of three CO2 treatments: control (22.1 ?? 2.8 mg/L), medium (34.5 ?? 3.8 mg/L), or high (48.7 ?? 4.4 mg/L). Trout were checked daily for survival, and fish were sampled at 0, 28, 56, and 84 d for physiological responses, growth, and fillet quality assessments. Trout were also challenged to a 15-min crowding stress at 93 d to assess their ability to initiate a stress response during hypercapnia. Chronically exposed trout showed nearly 100% survival through 84 d exposure (1 of 1,500 fish died). Growth and physiological results showed that increasing elevated CO2 concentrations result in corresponding decreased growth rates and CO2-specific physiological parameters: The medium and high CO2 treatments had significantly slower growth and subsequently smaller fish by 84 d. Exposed trout also showed significantly (P smoked fillet weights. Chronic CO2 exposure did not result in notable changes in ultimate muscle pH. Exposure to 15-min crowding stress at 93 d resulted in significant changes in hematocrit, plasma cortisol, glucose, and chloride for all treatment groups. CO2-specific changes were detected in hematocrit, plasma cortisol, and plasma chloride responses following the 15-min crowding stress. ?? Copyright by the World Aquaculture Society 2005.

  20. Increasing levels of dietary crystalline methionine affect plasma methionine profiles, ammonia excretion, and the expression of genes related to the hepatic intermediary metabolism in rainbow trout (Oncorhynchus mykiss)

    DEFF Research Database (Denmark)

    Rolland, Marine; Skov, Peter Vilhelm; Larsen, Bodil Katrine

    2016-01-01

    Strictly carnivorous fish with high requirements for dietary protein, such as rainbow trout (Oncorhynchus mykiss) are interesting models for studying the role of amino acids as key regulators of intermediary metabolism. Methionine is an essential amino acid for rainbow trout, and works as a signa......Strictly carnivorous fish with high requirements for dietary protein, such as rainbow trout (Oncorhynchus mykiss) are interesting models for studying the role of amino acids as key regulators of intermediary metabolism. Methionine is an essential amino acid for rainbow trout, and works...... as a signalling factor in different metabolic pathways. The study investigated the effect of increasing dietary methionine intake on the intermediary metabolism in the liver of juvenile rainbow trout. For this purpose, five diets were formulated with increasing methionine levels from 0.60 to 1.29% dry matter....... The diets were fed in excess for six weeks before three sampling campaigns carried out successively to elucidate (i) the hepatic expression of selected genes involved in lipid, glucose and amino acid metabolism; (ii) the postprandial ammonia excretion; and (iii) the postprandial plasma methionine...

  1. The malleable gut microbiome of juvenile rainbow trout (Oncorhynchus mykiss): Diet-dependent shifts of bacterial community structures.

    Science.gov (United States)

    Michl, Stéphanie Céline; Ratten, Jenni-Marie; Beyer, Matt; Hasler, Mario; LaRoche, Julie; Schulz, Carsten

    2017-01-01

    Plant-derived protein sources are the most relevant substitutes for fishmeal in aquafeeds. Nevertheless, the effects of plant based diets on the intestinal microbiome especially of juvenile Rainbow trout (Oncorhynchus mykiss) are yet to be fully investigated. The present study demonstrates, based on 16S rDNA bacterial community profiling, that the intestinal microbiome of juvenile Rainbow trout is strongly affected by dietary plant protein inclusion levels. After first feeding of juveniles with either 0%, 50% or 97% of total dietary protein content derived from plants, statistically significant differences of the bacterial gut community for the three diet-types were detected, both at phylum and order level. The microbiome of juvenile fish consisted mainly of the phyla Proteobacteria, Firmicutes, Bacteroidetes, Fusobacteria and Actinobacteria, and thus fits the salmonid core microbiome suggested in previous studies. Dietary plant proteins significantly enhanced the relative abundance of the orders Lactobacillales, Bacillales and Pseudomonadales. Animal proteins in contrast significantly promoted Bacteroidales, Clostridiales, Vibrionales, Fusobacteriales and Alteromonadales. The overall alpha diversity significantly decreased with increasing plant protein inclusion levels and with age of experimental animals. In order to investigate permanent effects of the first feeding diet-type on the early development of the microbiome, a diet change was included in the study after 54 days, but no such effects could be detected. Instead, the microbiome of juvenile trout fry was highly dependent on the actual diet fed at the time of sampling.

  2. The Effect of Mycotoxin Deoxynivalenol on Haematological and Biochemical Indicators and Histopathological Changes in Rainbow Trout (Oncorhynchus mykiss

    Directory of Open Access Journals (Sweden)

    Iveta Matejova

    2014-01-01

    Full Text Available Deoxynivalenol (DON, produced by the Fusarium genus, is a major contaminant of cereal grains used in the production of fish feed. The effect of mycotoxin deoxynivalenol on rainbow trout (Oncorhynchus mykiss was studied using a commercial feed with the addition of DON in a dose of 2 mg/kg feed. The fish (n=40 were exposed to the mycotoxin for 23 days. The trout were divided into two groups, control and experimental groups. Control groups were fed a commercial feed naturally contaminated with a low concentration of DON (225 μg/kg feed; experimental groups were fed a commercial feed with the addition of DON (1964 μg/kg feed. Plasma biochemical and haematological indices, biometric parameters, and histopathological changes were assessed at the end of the experiment. The experimental groups showed significantly lower values in MCH (P<0.05. In biochemical indices, after 23-day exposure, a significant decrease in glucose, cholesterol (P<0.05, and ammonia (P<0.01 was recorded in the experimental group compared to the control group. Our assessment showed no significant changes in biometric parameters. The histopathological examination revealed disorders in the caudal kidney of the exposed fish. The obtained data show the sensitivity of rainbow trout (O. mykiss to deoxynivalenol.

  3. The combine effects of salting and thyme oil on sensory and chemical changes of rainbow trout (Oncorhynchus mykiss) fillets

    Science.gov (United States)

    Yildiz, Pınar Oǧuzhan

    2016-04-01

    The present study aimed to investigate the combine effects of salting and thyme oil on chemical and sensory changes of rainbow trout (Oncorhynchus mykiss) during storage (4°C) was investigated over a period of 24 days. There groups were constituted: group A-control salted, group B-salted samples with 0.4% of thyme oil and group C-salted samples with 0.8% of thyme oil. Fillets were subject to chemical (thiobarbituric acid reactive substances-TBARS, total volatile base nitrogen-TVB-N) and sensory analyses on certain days (0, 3, 6, 9, 12, 15, 18, 21 and 24th days) of storage. Five experienced panelists, academic staff who were trained in sensory descriptors for fishes, were employed to evaluate the quality of trout fillets during storage. Rainbow trout fillets were assessed on the basis of appearance, taste, texture and odour characteristics using a nine point descriptive scale. TVB-N and TBARS values increased in the duration of storage time in all groups. TVB-N and TBARS values in control groups were higher than other groups. Group C samples were assessed as the most acceptable products by the panellists. Difference in chemical and sensory changes between samples was found to be significant (p<0.05) during storage period.

  4. Effects of canola meal on growth and digestion of rainbow trout (Oncorhynchus mykiss) fry

    OpenAIRE

    YİĞİT, Nalan Özgür; KOCA, Seval BAHADIR; BAYRAK, Halit; DULLUÇ, Arife; DİLER, İbrahim

    2012-01-01

    A 12-week feeding trial was conducted with rainbow trout fry (initial weight of 1.57 ± 0.01 g) to examine the effects of partial substitution of canola meal in prepared diets on growth, feed conversion ratio (FCR), nutrient digestibility, somatic indices, and survival rate. Five isonitrogenous (44% crude protein) and isocaloric (4000 kcal/kg digestible energy) diets were formulated to contain 8%, 16%, 24%, and 32% canola meal against no canola meal (control group). A total of 375 rainbow trou...

  5. The Share of Internal Organs and Viscera in Rainbow Trout (Oncorhynchus Mykiss Reared in Different Growth Systems

    Directory of Open Access Journals (Sweden)

    Daniel Cocan

    2012-10-01

    Full Text Available In this experiment we followed the influence of growth system on the share of internal organs and viscera by the total body mass on rainbow trout (Oncorhynchus mykiss. The importance of this study results from the need to reach as favourable slaughter yield. For this, were slaughtered 25 rainbow trout from the Fiad trout farm (conventional farm, Bistriţa-Năsăud County (control group – M, respectively 25 rainbow trout grown in a recirculating system arranged in Cluj-Napoca (experimental group – E. Body weight of the studied specimens was 228.96±1.21 g – M group, respectively 229.40±1.24 g – E group, the difference between the two groups being insignificant (p>0.05. The slaughter yield was favorable for E group – 90.55±0.03%, compared with M group – 89.23±0.05% (p<0.001. We analyzed the total gravimetric share of the internal organs and viscera at trout from the two groups and individual weights of esophagus, stomach, pyloric caeca, medium intestine and duodenum, rectum, liver, pancreas, heart, spleen, air bladder and kidney. The results showed a higher share of this organs at trout from the Fiad trout farm (M group, except stomach (2.38±0.01g – M group vs. 2.45±0.008 g – E group; p<0.05, and liver respectively (4.83±0.02 g – M group vs. 5.36±0.04 g – E group; p<0.001. In accordance with the values obtained, the resulting conclusion is that in the recirculating system, due to optimal environmental conditions, trout have a higher slaughter yield compared with those of conventional farm, accumulating in the same time fat reserves deposited in the liver.

  6. Aspects Regarding the Influence of Growth Technology Concerning the Performances Production of the Rainbow Trout (Oncorhynchus Mykiss

    Directory of Open Access Journals (Sweden)

    Daniel Cocan

    2012-10-01

    Full Text Available Experiments were conducted throughout 2009 and 2010. At the beginning of experiments, both in 2009 and in 2010, were formed two groups (M-control group; E-experimental group, each group far 600 rainbow trout (Oncorhynchus mykiss. Control group M has been exploited in the Fiad trout farm, Bistriţa-Năsăud County, and the experimental group E was operated in a recirculating system arranged in Cluj-Napoca. Experiments were conducted over 210 days, both in 2009 and in 2010. Initial body weight of the specimens was 22.70±0.40 g – group M, and 22.68±0.39 – group E, in 2009. In the second experimental series (2010, the initial body weight of the rainbow trout specimens was 22.69±0.28 g – group M, respectively 22.56±0.31 g – group E. As factors which influencing directly the growth dynamic of rainbow trout, were monitored the physico-chemical parameters of water from the two locations, and feed consumption. Production performances of the trout from the two experimental groups, were assessed using as indicators total weight gain (TWG and specific growth rate (SGR. In 2009, TWG=370.92±4.37 g – group E vs. 79.59±1.09 g – group M (p<0.001, and SGR=1.55±0.01 g/day – group E vs. 0.33±0.005 g/day – group M (p<0.001. In 2010, TWG=377.85±3.97 g – group E vs. 103.78±1.28 g – group M (p<0.001, and SGR=1.57±0.01 g/day – group E vs. 0.43±0.005 g/day – group M. Analyzing the two indicators (TWG and SGR, we can conclude that due to optimal environmental conditions provided by the recirculating system, the production performances of rainbow trout in both experimental series, were significantly higher in group E compared with group M.

  7. A comparative assessment of the adrenotoxic effects of cadmium in two teleost species, rainbow trout, Oncorhynchus mykiss, and yellow perch, Perca flavescens

    International Nuclear Information System (INIS)

    Lacroix, Alexandra; Hontela, Alice

    2004-01-01

    Rainbow trout (Oncorhynchus mykiss) and yellow perch (Perca flavescens) have a different sensitivity to cadmium (Cd) in vivo (trout O.mykiss =175.6>LC50/EC50 P.flavescens =37.7). Adrenocortical cells of trout were more sensitive than those of perch and Cd had a higher endocrine-disrupting potential and specificity in trout than in perch. However, in both species, Cd had the same effect on ACTH, dbcAMP and pregnenolone-stimulated cortisol secretion, with pregnenolone maintaining cortisol secretion until cell viability was impaired. These results confirm that for both species, Cd interferes in the signalling pathway of cortisol synthesis in a step prior to the pregnenolone formation. Data provided by the present study revealed important differences in vulnerability of adrenal steroidogenesis between rainbow trout and yellow perch

  8. Toxicogenomic responses in rainbow trout (Oncorhynchus mykiss) hepatocytes exposed to model chemicals and a synthetic mixture

    International Nuclear Information System (INIS)

    Finne, E.F.; Cooper, G.A.; Koop, B.F.; Hylland, K.; Tollefsen, K.E.

    2007-01-01

    As more salmon gene expression data has become available, the cDNA microarray platform has emerged as an appealing alternative in ecotoxicological screening of single chemicals and environmental samples relevant to the aquatic environment. This study was performed to validate biomarker gene responses of in vitro cultured rainbow trout (Oncorhynchus mykiss) hepatocytes exposed to model chemicals, and to investigate effects of mixture toxicity in a synthetic mixture. Chemicals used for 24 h single chemical- and mixture exposures were 10 nM 17α-ethinylestradiol (EE2), 0.75 nM 2,3,7,8-tetrachloro-di-benzodioxin (TCDD), 100 μM paraquat (PQ) and 0.75 μM 4-nitroquinoline-1-oxide (NQO). RNA was isolated from exposed cells, DNAse treated and quality controlled before cDNA synthesis, fluorescent labelling and hybridisation to a 16k salmonid microarray. The salmonid 16k cDNA array identified differential gene expression predictive of exposure, which could be verified by quantitative real time PCR. More precisely, the responses of biomarker genes such as cytochrome p4501A and UDP-glucuronosyl transferase to TCDD exposure, glutathione reductase and gammaglutamyl cysteine synthetase to paraquat exposure, as well as vitellogenin and vitelline envelope protein to EE2 exposure validated the use of microarray applied to RNA extracted from in vitro exposed hepatocytes. The mutagenic compound NQO did not result in any change in gene expression. Results from exposure to a synthetic mixture of the same four chemicals, using identical concentrations as for single chemical exposures, revealed combined effects that were not predicted by results for individual chemicals alone. In general, the response of exposure to this mixture led to an average loss of approximately 60% of the transcriptomic signature found for single chemical exposure. The present findings show that microarray analyses may contribute to our mechanistic understanding of single contaminant mode of action as well as

  9. Puffy Skin Disease Is an Emerging Transmissible Condition in Rainbow Trout Oncorhynchus mykiss Walbaum.

    Science.gov (United States)

    Cano, Irene; Verner-Jeffreys, David W; van Aerle, Ronny; Paley, Richard K; Peeler, Edmund J; Green, Matthew; Rimmer, Georgina S E; Savage, Jacqueline; Joiner, Claire L; Bayley, Amanda E; Mewett, Jason; Hulland, Jonathan; Feist, Stephen W

    2016-01-01

    The transmission of puffy skin disease (PSD) to rainbow trout Oncorhynchus mykiss Walbaum was tested in the laboratory by conducting co-habitation challenges with puffy skin (PS)-affected fish (Trojans) collected from the field. Two separate challenges were conducted using Trojans sourced from two different sites and diploid (first trial) or triploid (second trial) naïve fish. PSD-specific clinical signs were observed in both groups of naïve fish, with 66% of the fish sampled during the challenges showing signs of varying severity. The first clinical features of PSD were presented as white oval skin patches on one or both flanks 15-21 days post-challenge (dpc). The extent of the lesions ranged from 10 to 90% of the body surface, depending on the severity of the lesion. Both the severity and number of affected fish increased during the challenge. Macroscopically, oedema of the skin and multifocal petechial haemorrhaging were observed towards the end of the trials. Abnormal fish behaviour consisting of "flashing" and excessive mucous production was noted from 15 dpc onwards. Fish with severe PSD lesions also displayed inappetence and associated emaciation. Rodlet cells were observed in 41% of the fresh skin scrapes analysed from the second trial. Histologically epidermal oedema was observed in 31% of the naive fish showing gross pathology, with additional 12% displaying epidermal hyperplasia, mostly observed at the end of the challenge. Other concomitant features of the PSD lesions in challenged fish were epithelial erosion and sloughing, and occasionally mild or focal inflammation. No consistent pathology of internal organs was observed. The parasites Ichthyophthirius multifiliis and Ichthyobodo necator were observed in skin samples of a proportion of naïve challenged fish and in Trojans but not in control fish. The presence of these and other known fish pathogens in the skin of PSD-fish was confirmed by high-throughput sequencing analysis. In summary, we have

  10. Toxicogenomic responses in rainbow trout (Oncorhynchus mykiss) hepatocytes exposed to model chemicals and a synthetic mixture

    Energy Technology Data Exchange (ETDEWEB)

    Finne, E.F. [Norwegian Institute for Water Research, Gaustadalleen 21, N-0349 Oslo (Norway) and University of Oslo, Department of Biology, P.O. Box 1066, Blindern, N-0316 Oslo (Norway)]. E-mail: eivind.finne@niva.no; Cooper, G.A. [Centre for Biomedical Research, University of Victoria, BC V8P5C2 (Canada); Koop, B.F. [Centre for Biomedical Research, University of Victoria, BC V8P5C2 (Canada); Hylland, K. [Norwegian Institute for Water Research, Gaustadalleen 21, N-0349 Oslo (Norway); University of Oslo, Department of Biology, P.O. Box 1066, Blindern, N-0316 Oslo (Norway); Tollefsen, K.E. [Norwegian Institute for Water Research, Gaustadalleen 21, N-0349 Oslo (Norway)

    2007-03-10

    As more salmon gene expression data has become available, the cDNA microarray platform has emerged as an appealing alternative in ecotoxicological screening of single chemicals and environmental samples relevant to the aquatic environment. This study was performed to validate biomarker gene responses of in vitro cultured rainbow trout (Oncorhynchus mykiss) hepatocytes exposed to model chemicals, and to investigate effects of mixture toxicity in a synthetic mixture. Chemicals used for 24 h single chemical- and mixture exposures were 10 nM 17{alpha}-ethinylestradiol (EE2), 0.75 nM 2,3,7,8-tetrachloro-di-benzodioxin (TCDD), 100 {mu}M paraquat (PQ) and 0.75 {mu}M 4-nitroquinoline-1-oxide (NQO). RNA was isolated from exposed cells, DNAse treated and quality controlled before cDNA synthesis, fluorescent labelling and hybridisation to a 16k salmonid microarray. The salmonid 16k cDNA array identified differential gene expression predictive of exposure, which could be verified by quantitative real time PCR. More precisely, the responses of biomarker genes such as cytochrome p4501A and UDP-glucuronosyl transferase to TCDD exposure, glutathione reductase and gammaglutamyl cysteine synthetase to paraquat exposure, as well as vitellogenin and vitelline envelope protein to EE2 exposure validated the use of microarray applied to RNA extracted from in vitro exposed hepatocytes. The mutagenic compound NQO did not result in any change in gene expression. Results from exposure to a synthetic mixture of the same four chemicals, using identical concentrations as for single chemical exposures, revealed combined effects that were not predicted by results for individual chemicals alone. In general, the response of exposure to this mixture led to an average loss of approximately 60% of the transcriptomic signature found for single chemical exposure. The present findings show that microarray analyses may contribute to our mechanistic understanding of single contaminant mode of action as

  11. Ammonia and nitrite removal rates in a closed recirculating-water system, under three load rates of rainbow trout Oncorhynchus mykiss

    OpenAIRE

    Arredondo-Figueroa, J. L.; Ingle de la Mora, G; Guerrero-Legarreta, I; Ponce-Palafox, J. T.; Barriga-Sosa, I. de los A.

    2007-01-01

    Nitrification and denitrification rates of inorganic nitrogen were studied in a closed recirculating-water system, comparing three load rates of rainbow trout Oncorhynchus mykiss (89, 156 and 194 kg in each tank with two repetitions). Six self-cleaning water circular fish tanks with a volume of 4.3 m³ were used, maintaining a 3.94 m³/day of average flow rate and constant aeration. A total of 371 rainbow trout, 524 ± 8 g initial wet weight were introduced in the system and fed with a commercia...

  12. Purification and characterization of elastase from the pyloric caeca of rainbow trout (Oncorhynchus mykiss)

    DEFF Research Database (Denmark)

    Bassompierre, Marc; Nielsen, Henrik Hauch; Børresen, Torger

    1993-01-01

    1. An elastase-like enzyme was purified from the pyloric caeca of rainbow trout by hydrophobic interaction, cation exchange and gel-filtration chromatography. 2. The approximate molecular weight of the elastase was 27 kDa and the isoelectric point was remarkably basic. 3. The pH optimum of this e......1. An elastase-like enzyme was purified from the pyloric caeca of rainbow trout by hydrophobic interaction, cation exchange and gel-filtration chromatography. 2. The approximate molecular weight of the elastase was 27 kDa and the isoelectric point was remarkably basic. 3. The pH optimum...... of this enzyme was 8.0, when assayed with Succinyl-Ala-Ala-Ala-p-Nitroanilide. 4. When assayed with Succinyl-Ala-Ala-Ala-p-Nitroanilide, the enzyme activity had a temperature optimum of 45 degree C, and the enzyme was stable up to this temperature. 5. The trout elastase exhibited a higher specific activity than...... porcine elastase against Succinyl-Ala-Ala-Ala-p-Nitroanilide and elastin-orcein. 6. The trout elastase was inhibited by elastatinal, PMSF, TPCK, SBTI and Bowman-Birk inhibitor....

  13. Stress response of lead-exposed rainbow trout (Oncorhynchus mykiss) during swimming performance and hypoxia challenges

    Energy Technology Data Exchange (ETDEWEB)

    Phillips, K.A. [National Biological Service, La Crosse, WI (United States)]|[Univ. of Wisconsin, La Crosse, WI (United States); Caldwell, C.A. [National Biological Service, La Crosse, WI (United States); Sandheinrich, M.B. [Univ. of Wisconsin, La Crosse, WI (United States)

    1995-12-31

    Contaminants often invoke a stress response in aquatic organisms, and may compromise their capacity to respond to secondary stressors. This may reduce growth, reproduction and survival. The authors objectives were to assess the effects of lead and secondary stressors on hematology and blood chemistry of rainbow trout. After a 7 to 8-week aqueous exposure to Pb(100{micro}g/L), rainbow trout were challenged with forced swimming or hypoxia. Lead significantly reduced concentrations of 5-aminolevulinic acid dehydratase (ALAD), but not other constituents in the blood. Lead did not affect the swimming endurance of the fish. Hematocrit, mean cell hemoglobin content, and mean cell volume were significantly lower in Pb-exposed trout following the swimming challenge. Although hypoxia resulted in increased hematocrit and plasma glucose concentrations, there were no significant differences between the Pb and control groups. Hypoxia did not affect plasma chloride concentrations, although concentrations increased in Pb-exposed trout. There was no difference in lactic acid concentrations between Pb-exposed and control fish after forced swimming or hypoxia.

  14. Effects of varying densities on serum reproductive parameters in pen-reared juvenile female rainbow trout Oncorhynchus mykiss farms

    Science.gov (United States)

    Hou, Zhishuai; Wen, Haishen; Li, Jifang; He, Feng; Liu, Qun; Wang, Jinhuan; Guan, Biao; Wang, Qinglong

    2017-01-01

    The primary goal of this study was to assess the effect of varying densities on serum reproductive parameters of immature rainbow trout Oncorhynchus mykiss. Experimental trout were maintained in intensive, pen-reared farms for 300 days in fresh water reservoirs. Initial densities were 4.6, 6.6, and 8.6 kg/m3 (40, 60, 80 ind./m3), indicated as SD1, SD2, SD3, and final densities were 31.1, 40.6, 49.3 kg/m3, respectively. A summary of the ovarian stages were observed by histological examination. Serum E2 (estradiol), T (testosterone) were evaluated by radioimmunoassay and FSH (follicle-stimulating-hormone), LH (luteinizing-hormone), vitellogenin, 17α,20β-P (17α,20βdihydroxy4-pregnen-3-one) were measured by enzyme-linked immunosorbent assay. Our findings demonstrated that ovarian development were retarded (from stage III to stage IV) at highest rearing density (SD3) after 180 days of intensive culture (over 40.6 kg/m3). In addition, we observed an inverse relationship between serum reproductive parameters and rearing density. Furthermore, compared to serum reproductive parameters of SD1, E2, T, FSH, vitellogenin, 17α,20β-P, GSI and LH of two higher density groups decreased firstly and significantly at 60 (over 15.9 kg/m 3 ), 180 (over 31.7 kg/m 3 ), 180 (over 40.6 kg/m3), 240 (over 36 kg/m3), 240 (over 36 kg/m3), 240 (over 45 kg/m3) and 300 (over 49.3 kg/m3) days, respectively. Comparing serum reproductive parameters within the same ovarian development stage of rainbow trout from varying densities revealed that higher population density also led to significantly lower overall serum reproductive parameters. Overall, this study presents the reproductive, endocrinological parameters of juvenile female rainbow trout at high rearing densities and indicates the need for rainbow trout (114.44±5.21 g, 19.69±0.31 cm) that are initially stocked at 6.6 or 8.6 kg/m3 should be classified and subdivided into lower density after 180 days of farming (not over 31.7 kg/m3).

  15. Bioaccumulation and subcellular partitioning of zinc in rainbow trout (Oncorhynchus mykiss): Cross-talk between waterborne and dietary uptake

    International Nuclear Information System (INIS)

    Sappal, Ravinder; Burka, John; Dawson, Susan; Kamunde, Collins

    2009-01-01

    Zinc homeostasis was studied at the tissue and gill subcellular levels in rainbow trout (Oncorhynchus mykiss) following waterborne and dietary exposures, singly and in combination. Juvenile rainbow trout were exposed to 150 or 600 μg l -1 waterborne Zn, 1500 or 4500 μg g -1 dietary Zn, and a combination of 150 μg l -1 waterborne and 1500 μg g -1 dietary Zn for 40 days. Accumulation of Zn in tissues and gill subcellular fractions was measured. At the tissue level, the carcass acted as the main Zn depot containing 84-90% of whole body Zn burden whereas the gill held 4-6%. At the subcellular level, the majority of gill Zn was bioavailable with the estimated metabolically active pool being 81-90%. Interestingly, the nuclei-cellular debris fraction bound the highest amount (40%) of the gill Zn burden. There was low partitioning of Zn into the detoxified pool (10-19%) suggesting that sequestration and chelation are not major mechanisms of cellular Zn homeostasis in rainbow trout. Further, the subcellular partitioning of Zn did not conform to the spill-over model of metal toxicity because Zn binding was indiscriminate irrespective of exposure concentration and duration. The contribution of the branchial and gastrointestinal uptake pathways to Zn accumulation depended on the tissue. Specifically, in plasma, blood cells, and gill, uptake from water was dominant whereas both pathways appeared to contribute equally to Zn accumulation in the carcass. Subcellularly, additive uptake from the two pathways was observed in the heat-stable proteins (HSP) fraction. Toxicologically, Zn exposure caused minimal adverse effects manifested by a transitory inhibition of protein synthesis in gills in the waterborne exposure. Overall, subcellular fractionation appears to have value in the quest for a better understanding of Zn homeostasis and interactions between branchial and gastrointestinal uptake pathways

  16. Bioaccumulation and subcellular partitioning of zinc in rainbow trout (Oncorhynchus mykiss): Cross-talk between waterborne and dietary uptake

    Energy Technology Data Exchange (ETDEWEB)

    Sappal, Ravinder; Burka, John; Dawson, Susan [Department of Biomedical Sciences, Atlantic Veterinary College, University of Prince Edward Island, Charlottetown, PE C1A 4P3 (Canada); Kamunde, Collins [Department of Biomedical Sciences, Atlantic Veterinary College, University of Prince Edward Island, Charlottetown, PE C1A 4P3 (Canada)], E-mail: ckamunde@upei.ca

    2009-03-09

    Zinc homeostasis was studied at the tissue and gill subcellular levels in rainbow trout (Oncorhynchus mykiss) following waterborne and dietary exposures, singly and in combination. Juvenile rainbow trout were exposed to 150 or 600 {mu}g l{sup -1} waterborne Zn, 1500 or 4500 {mu}g g{sup -1} dietary Zn, and a combination of 150 {mu}g l{sup -1} waterborne and 1500 {mu}g g{sup -1} dietary Zn for 40 days. Accumulation of Zn in tissues and gill subcellular fractions was measured. At the tissue level, the carcass acted as the main Zn depot containing 84-90% of whole body Zn burden whereas the gill held 4-6%. At the subcellular level, the majority of gill Zn was bioavailable with the estimated metabolically active pool being 81-90%. Interestingly, the nuclei-cellular debris fraction bound the highest amount (40%) of the gill Zn burden. There was low partitioning of Zn into the detoxified pool (10-19%) suggesting that sequestration and chelation are not major mechanisms of cellular Zn homeostasis in rainbow trout. Further, the subcellular partitioning of Zn did not conform to the spill-over model of metal toxicity because Zn binding was indiscriminate irrespective of exposure concentration and duration. The contribution of the branchial and gastrointestinal uptake pathways to Zn accumulation depended on the tissue. Specifically, in plasma, blood cells, and gill, uptake from water was dominant whereas both pathways appeared to contribute equally to Zn accumulation in the carcass. Subcellularly, additive uptake from the two pathways was observed in the heat-stable proteins (HSP) fraction. Toxicologically, Zn exposure caused minimal adverse effects manifested by a transitory inhibition of protein synthesis in gills in the waterborne exposure. Overall, subcellular fractionation appears to have value in the quest for a better understanding of Zn homeostasis and interactions between branchial and gastrointestinal uptake pathways.

  17. Isocitrate dehydrogenase mutation in Vibrio anguillarum results in virulence attenuation and immunoprotection in rainbow trout (Oncorhynchus mykiss).

    Science.gov (United States)

    Mou, Xiangyu; Spinard, Edward J; Hillman, Shelby L; Nelson, David R

    2017-11-14

    Vibrio anguillarum is an extracellular bacterial pathogen that is a causative agent of vibriosis in finfish and crustaceans with mortality rates ranging from 30% to 100%. Mutations in central metabolism (glycolysis and the TCA cycle) of intracellular pathogens often result in attenuated virulence due to depletion of required metabolic intermediates; however, it was not known whether mutations in central metabolism would affect virulence in an extracellular pathogen such as V. anguillarum. Seven central metabolism mutants were created and characterized with regard to growth in minimal and complex media, expression of virulence genes, and virulence in juvenile rainbow trout (Oncorhynchus mykiss). Only the isocitrate dehydrogenase (icd) mutant was attenuated in virulence against rainbow trout challenged by either intraperitoneal injection or immersion. Further, the icd mutant was shown to be immunoprotective against wild type V. anguillarum infection. There was no significant decrease in the expression of the three hemolysin genes detected by qRT-PCR. Additionally, only the icd mutant exhibited a significantly decreased growth yield in complex media. Growth yield was directly related to the abundance of glutamate. A strain with a restored wild type icd gene was created and shown to restore growth to a wild type cell density in complex media and pathogenicity in rainbow trout. The data strongly suggest that a decreased growth yield, resulting from the inability to synthesize α-ketoglutarate, caused the attenuation despite normal levels of expression of virulence genes. Therefore, the ability of an extracellular pathogen to cause disease is dependent upon the availability of host-supplied nutrients for growth. Additionally, a live vaccine strain could be created from an icd deletion strain.

  18. Immune-Specific Expression and Estrogenic Regulation of the Four Estrogen Receptor Isoforms in Female Rainbow Trout (Oncorhynchus mykiss

    Directory of Open Access Journals (Sweden)

    Ayako Casanova-Nakayama

    2018-03-01

    Full Text Available Genomic actions of estrogens in vertebrates are exerted via two intracellular estrogen receptor (ER subtypes, ERα and ERβ, which show cell- and tissue-specific expression profiles. Mammalian immune cells express ERs and are responsive to estrogens. More recently, evidence became available that ERs are also present in the immune organs and cells of teleost fish, suggesting that the immunomodulatory function of estrogens has been conserved throughout vertebrate evolution. For a better understanding of the sensitivity and the responsiveness of the fish immune system to estrogens, more insight is needed on the abundance of ERs in the fish immune system, the cellular ratios of the ER subtypes, and their autoregulation by estrogens. Consequently, the aims of the present study were (i to determine the absolute mRNA copy numbers of the four ER isoforms in the immune organs and cells of rainbow trout, Oncorhynchus mykiss, and to compare them to the hepatic ER numbers; (ii to analyse the ER mRNA isoform ratios in the immune system; and, (iii finally, to examine the alterations of immune ER mRNA expression levels in sexually immature trout exposed to 17β-estradiol (E2, as well as the alterations of immune ER mRNA expression levels in sexually mature trout during the reproductive cycle. All four ER isoforms were present in immune organs—head kidney, spleen-and immune cells from head kidney and blood of rainbow trout, but their mRNA levels were substantially lower than in the liver. The ER isoform ratios were tissue- and cell-specific, both within the immune system, but also between the immune system and the liver. Short-term administration of E2 to juvenile female trout altered the ER mRNA levels in the liver, but the ERs of the immune organs and cells were not responsive. Changes of ER gene transcript numbers in immune organs and cells occurred during the reproductive cycle of mature female trout, but the changes in the immune ER profiles differed

  19. Effect of short-term decrease in water temperature on body temperature and involvement of testosterone in steelhead and rainbow trout, Oncorhynchus mykiss.

    Science.gov (United States)

    Miura, Go; Munakata, Arimune; Yada, Takashi; Schreck, Carl B; Noakes, David L G; Matsuda, Hiroyuki

    2013-09-01

    The Pacific salmonid species Oncorhynchus mykiss is separated into a migratory form (steelhead trout) and a non-migratory form (rainbow trout). A decrease in water temperature is likely a cue triggering downstream behavior in the migratory form, and testosterone inhibits onset of this behavior. To elucidate differences in sensitivity to water temperature decreases between the migratory and non-migratory forms and effect of testosterone on the sensitivity, we examined two experiments. In experiment 1, we compared changes in body temperature during a short-term decrease in water temperature between both live and dead steelhead and rainbow trout. In experiment 2, we investigated effects of testosterone on body temperature decrease in steelhead trout. Water temperature was decreased by 3°C in 30min. The body temperature of the steelhead decreased faster than that of the rainbow trout. In contrast, there was no significant difference in the decrease in body temperature between dead steelhead and rainbow trout specimens. The body temperature of the testosterone-treated steelhead trout decreased more slowly than that of control fish. Our results suggest that the migratory form is more sensitive to decreases in water temperature than the non-migratory form. Moreover, testosterone might play an inhibitory role in sensitivity to such decreases. Copyright © 2013 Elsevier Inc. All rights reserved.

  20. Estimation of genetic parameters for growth traits in a breeding program for rainbow trout (Oncorhynchus mykiss) in China.

    Science.gov (United States)

    Hu, G; Gu, W; Bai, Q L; Wang, B Q

    2013-04-26

    Genetic parameters and breeding values for growth traits were estimated in the first and, currently, the only family selective breeding program for rainbow trout (Oncorhynchus mykiss) in China. Genetic and phenotypic data were collected for growth traits from 75 full-sibling families with a 2-generation pedigree. Genetic parameters and breeding values for growth traits of rainbow trout were estimated using the derivative-free restricted maximum likelihood method. The goodness-of-fit of the models was tested using Akaike and Bayesian information criteria. Genetic parameters and breeding values were estimated using the best-fit model for each trait. The values for heritability estimating body weight and length ranged from 0.20 to 0.45 and from 0.27 to 0.60, respectively, and the heritability of condition factor was 0.34. Our results showed a moderate degree of heritability for growth traits in this breeding program and suggested that the genetic and phenotypic tendency of body length, body weight, and condition factor were similar. Therefore, the selection of phenotypic values based on pedigree information was also suitable in this research population.

  1. Effect of gamma radiation on the growth, survival, hematology and histological parameters of rainbow trout (Oncorhynchus mykiss) larvae

    Energy Technology Data Exchange (ETDEWEB)

    Oujifard, Amin, E-mail: oujifard.amin@gmail.com [Fisheries Department, Faculty of Agriculture and Natural Resources, Persian Gulf University, Borazjan, Bushehr (Iran, Islamic Republic of); Amiri, Roghayeh [Department of Veterinary, Agricultural Medical and Industrial Research School, Nuclear Science and Technology Research Institute, AEOI, Karaj (Iran, Islamic Republic of); Shahhosseini, Gholamreza [Fisheries Department, Faculty of Natural Resources and Marine Sciences, TarbiatModares University, Noor, Mazandaran (Iran, Islamic Republic of); Davoodi, Reza [Fisheries Department, Faculty of Agriculture and Natural Resources, Persian Gulf University, Borazjan, Bushehr (Iran, Islamic Republic of); Moghaddam, Jamshid Amiri [Fisheries Department, Faculty of Natural Resources and Marine Sciences, TarbiatModares University, Noor, Mazandaran (Iran, Islamic Republic of)

    2015-08-15

    Highlights: • Incrementing of gamma radiation reveals the negative effects on fish larvae. • Radiation adversely affected the weight, blood cells and intestinal morphology of the larvae. • No mortality was observed at low dosage of gamma radiation on fish larvae. - Abstract: Effects of low (1, 2.5 and 5 Gy) and high doses (10, 20 and 40 Gy) of gamma radiation were examined on the growth, survival, blood parameters and morphological changes of the intestines of rainbow trout (Oncorhynchus mykiss) larvae (103 ± 20 mg) after 12 weeks of exposure. Negative effects of gamma radiation on growth and survival were observed as radiation level and time increased. Changes were well documented at 10 and 20 Gy. All the fish were dead at the dose of 40 Gy. In all the treatments, levels of red blood cells (RBC), hematocrit (HCT) and hemoglobin (HB) were significantly (P < 0.05) declined as the irradiation levels increased, whereas the amount of mean corpuscular volume (MCV) and mean corpuscular hemoglobin (MCH) did not change. No significant differences (P > 0.05) were found in the levels of white blood cells (WBC), lymphocytes and monocytes. Destruction of the intestinal epithelium cells was indicated as the irradiation levels increased to 1 Gy and above. The highest levels of growth, survival, specific growth rate (SGR), condition factor (CF) and protein efficiency rate (PER) were obtained in the control treatment. The results showed that gamma rays can be a potential means for damaging rainbow trout cells.

  2. Effect of gamma radiation on the growth, survival, hematology and histological parameters of rainbow trout (Oncorhynchus mykiss) larvae

    International Nuclear Information System (INIS)

    Oujifard, Amin; Amiri, Roghayeh; Shahhosseini, Gholamreza; Davoodi, Reza; Moghaddam, Jamshid Amiri

    2015-01-01

    Highlights: • Incrementing of gamma radiation reveals the negative effects on fish larvae. • Radiation adversely affected the weight, blood cells and intestinal morphology of the larvae. • No mortality was observed at low dosage of gamma radiation on fish larvae. - Abstract: Effects of low (1, 2.5 and 5 Gy) and high doses (10, 20 and 40 Gy) of gamma radiation were examined on the growth, survival, blood parameters and morphological changes of the intestines of rainbow trout (Oncorhynchus mykiss) larvae (103 ± 20 mg) after 12 weeks of exposure. Negative effects of gamma radiation on growth and survival were observed as radiation level and time increased. Changes were well documented at 10 and 20 Gy. All the fish were dead at the dose of 40 Gy. In all the treatments, levels of red blood cells (RBC), hematocrit (HCT) and hemoglobin (HB) were significantly (P < 0.05) declined as the irradiation levels increased, whereas the amount of mean corpuscular volume (MCV) and mean corpuscular hemoglobin (MCH) did not change. No significant differences (P > 0.05) were found in the levels of white blood cells (WBC), lymphocytes and monocytes. Destruction of the intestinal epithelium cells was indicated as the irradiation levels increased to 1 Gy and above. The highest levels of growth, survival, specific growth rate (SGR), condition factor (CF) and protein efficiency rate (PER) were obtained in the control treatment. The results showed that gamma rays can be a potential means for damaging rainbow trout cells

  3. The effects of acute waterborne exposure to sublethal concentrations of molybdenum on the stress response in rainbow trout, Oncorhynchus mykiss.

    Directory of Open Access Journals (Sweden)

    Chelsea D Ricketts

    Full Text Available To determine if molybdenum (Mo is a chemical stressor, fingerling and juvenile rainbow trout (Oncorhynchus mykiss were exposed to waterborne sodium molybdate (0, 2, 20, or 1,000 mg l-1 of Mo and components of the physiological (plasma cortisol, blood glucose, and hematocrit and cellular (heat shock protein [hsp] 72, hsp73, and hsp90 in the liver, gills, heart, and erythrocytes and metallothionein [MT] in the liver and gills stress responses were measured prior to initiation of exposure and at 8, 24, and 96 h. During the acute exposure, plasma cortisol, blood glucose, and hematocrit levels remained unchanged in all treatments. Heat shock protein 72 was not induced as a result of exposure and there were no detectable changes in total hsp70 (72 and 73, hsp90, and MT levels in any of the tissues relative to controls. Both fingerling and juvenile fish responded with similar lack of apparent sensitivity to Mo exposure. These experiments demonstrate that exposure to waterborne Mo of up to 1,000 mg l(-1 did not activate a physiological or cellular stress response in fish. Information from this study suggests that Mo water quality guidelines for the protection of aquatic life are highly protective of freshwater fish, namely rainbow trout.

  4. Growth performance and haematological and immunological indices of rainbow trout (Oncorhynchus mykiss fingerlings supplemented with dietary Ferulago angulata (Schlecht Boiss

    Directory of Open Access Journals (Sweden)

    Somayeh Bohlouli

    2016-01-01

    Full Text Available In this study, the effects of Ferulago angulata extract on the growth, haematological, and immunological indices of rainbow trout (Oncorhynchus mykiss fingerlings were evaluated. Basal diet was supplemented with 0 (control, 0.5, 1, and 2 g·kg-1 F. angulata and was randomly allocated to experimental fish of an initial average weight of 7.45 ± 0.02 g. After 8 weeks of experiment, the fish supplemented with F. angulata extract showed increased but non-significant (P > 0.05 growth performance. No significant differences were found between trial control groups in haematological indices such as red blood cell count, haematocrit, and haemoglobin, but there was a significant increase in white blood cells, lymphocytes, neutrophils and monocytes in the F. angulata extract groups (P < 0.05. Also, there were significant differences between the fish supplemented with dietary F. angulata extract and the control group regarding immunological indices, including immunoglobulin M, lysozyme, and classical and alternative complement pathway (P < 0.05. These findings suggest that the administration of F. angulata extract has a positive effect on the immunological indices and the immune system activity in rainbow trout fingerling.

  5. The Effects of Acute Waterborne Exposure to Sublethal Concentrations of Molybdenum on the Stress Response in Rainbow Trout, Oncorhynchus mykiss

    Science.gov (United States)

    Ricketts, Chelsea D.; Bates, William R.; Reid, Scott D.

    2015-01-01

    To determine if molybdenum (Mo) is a chemical stressor, fingerling and juvenile rainbow trout (Oncorhynchus mykiss) were exposed to waterborne sodium molybdate (0, 2, 20, or 1,000 mg l-1 of Mo) and components of the physiological (plasma cortisol, blood glucose, and hematocrit) and cellular (heat shock protein [hsp] 72, hsp73, and hsp90 in the liver, gills, heart, and erythrocytes and metallothionein [MT] in the liver and gills) stress responses were measured prior to initiation of exposure and at 8, 24, and 96 h. During the acute exposure, plasma cortisol, blood glucose, and hematocrit levels remained unchanged in all treatments. Heat shock protein 72 was not induced as a result of exposure and there were no detectable changes in total hsp70 (72 and 73), hsp90, and MT levels in any of the tissues relative to controls. Both fingerling and juvenile fish responded with similar lack of apparent sensitivity to Mo exposure. These experiments demonstrate that exposure to waterborne Mo of up to 1,000 mg l-1 did not activate a physiological or cellular stress response in fish. Information from this study suggests that Mo water quality guidelines for the protection of aquatic life are highly protective of freshwater fish, namely rainbow trout. PMID:25629693

  6. Molecular cloning and functional analysis of nucleotide-binding oligomerization domain-containing protein 1 in rainbow trout, Oncorhynchus mykiss.

    Science.gov (United States)

    Jang, Ju Hye; Kim, Hyun; Kim, Yu Jin; Cho, Ju Hyun

    2016-04-01

    NOD1 has important roles in innate immunity as sensor of microbial components derived from bacterial peptidoglycan. In this study, we identified genes encoding components of the NOD1 signaling pathway, including NOD1 (OmNOD1) and RIP2 (OmRIP2) from rainbow trout, Oncorhynchus mykiss, and investigated whether OmNOD1 has immunomodulating activity in a rainbow trout hepatoma cell line RTH-149 treated with NOD1-specific ligand (iE-DAP). The deduced amino acid sequence of OmNOD1 contained conserved CARD, NOD and LRR domains. Loss-of-function and gain-of-function experiments indicated that OmNOD1 is involved in the expression of pro-inflammatory cytokines. Silencing of OmNOD1 in RTH-149 cells treated with iE-DAP decreased the expression of IL-1β, IL-6, IL-8 and TNF-α. Conversely, overexpression of OmNOD1 resulted in up-regulation of IL-1β, IL-6, IL-8 and TNF-α expression. In addition, RIP2 inhibitor (gefitinib) significantly decreased the expression of these pro-inflammatory cytokines induced by iE-DAP in RTH-149 cells. These findings highlight the important role of NOD1 signaling pathway in fish in eliciting innate immune response. Copyright © 2016 Elsevier Ltd. All rights reserved.

  7. Molecular cloning and functional characterization of peptidoglycan recognition protein OmPGRP-L2 from the rainbow trout, Oncorhynchus mykiss.

    Science.gov (United States)

    Jang, Ju Hye; Kim, Hyun; Cho, Ju Hyun

    2017-10-01

    Peptidoglycan recognition proteins (PGRPs), a group of pattern recognition receptors (PRRs), are innate immune molecules that are structurally conserved through evolution in both invertebrate and vertebrate animals. In teleost fish, several PGRPs have been characterized recently. They have both amidase activity and bactericidal activity and are involved in indirectly killing bacteria and regulating multiple signaling pathways. However, the knowledge of functional similarity and divergence between PGRP paralogs for their role as an immune modulator in teleost fish is still limited. In this study, we identified a novel PGRP paralog, termed OmPGRP-L2 from the rainbow trout (Oncorhynchus mykiss). OmPGRP-L2 contains the conserved PGRP domain and the four Zn 2+ -binding amino acid residues required for amidase activity. Quantitative RT-PCR analysis indicated that OmPGRP-L2 is highly expressed in liver. Overexpression of OmPGRP-L2 in a rainbow trout hepatocyte cell line RTH-149 challenged with Edwardsiella tarda resulted in down-regulation of IL-1β and TNF-α expression. When overexpressed in RTH-149 cells, OmPGRP-L2 inhibited NF-κB activity with or without bacterial stimulation. Collectively, these findings suggest that OmPGRP-L2 has an immunomodulatory function, via NF-κB inhibition in liver. Copyright © 2017 Elsevier B.V. All rights reserved.

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

    Science.gov (United States)

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

    1998-04-01

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

  9. Effects of exercise training and coronary ablation on swimming performance, heart size, and cardiac enzymes in rainbow trout, Oncorhynchus mykiss

    DEFF Research Database (Denmark)

    FARRELL, AP; JOHANSEN, JA; STEFFENSEN, JF

    1990-01-01

    Rainbow trout, Oncorhynchus mykiss, were exercise trained for 28-52 days. Trained fish were 13% larger and swam 12% faster in an aerobic swimming test. Training induced cardiac growth that was isometric with body growth, since ventricle mass relative to body mass was constant. The proportions...... of compact and spongy myocardia in the ventricle were also unchanged by training. Trained fish had significantly higher levels of citrate synthase, ß-hydroxyacyl CoA dehydrogenase, and hexokinase in both compact and spongy myocardium. Ligation of a 0.5- to 1.0-cm section of the coronary artery produced only...... a temporary interruption of coronary flow to the compact myocardium because new vessels grew around the ligation site in the majority of fish during the 28- to 52-day experiment. Nonetheless, coronary ligation resulted in a significantly smaller (17%) proportion of compact myocardium with lower levels...

  10. Effects of supplemental enzymes on apparent nutrient digestibility in rainbow trout (Oncorhynchus mykiss) fed plant-based diets

    DEFF Research Database (Denmark)

    Dalsgaard, Anne Johanne Tang; Hjermitslev, Niels Harthøj; Ekmann, Kim Schøn

    2010-01-01

    in fish feed due to growing demands for and high price variations in fish meal, but high inclusion levels in diets for carnivorous fish are hampered by a great variety of anti-nutritional factors (ANFs), which reduce nutrient utilisation. Exogenous dietary enzymes may potentially help to alleviate...... on the effects of enzymes in fish feed apart from phytase. Phytase works by hydrolyzing phytic acid, and numerous studies have documented that phytase supplementation increases phosphorus availability in fish fed diets with high inclusion levels of plant proteins. Plant derived proteins are increasingly used...... these effects, and the objective of the present study was to evaluate the effects of supplementing protease and pectinase to a diet containing approximately 30% soybean meal, rapeseed meal or sunflower meal on nutrient digestibility in juvenile rainbow trout (Oncorhynchus mykiss). Digestibility trials were...

  11. Supplementing enzymes to extruded, soybean based diet improves breakdown of non-starch polysaccharides in rainbow trout (Oncorhynchus mykiss)

    DEFF Research Database (Denmark)

    Dalsgaard, Anne Johanne Tang; Knudsen, Knud Erik Bach; Verlhac, Viviane

    2016-01-01

    Plant-based feed ingredients typically contain remnants of dietary fibres [DF; non-starch polysaccharides (NSP) and lignin] that have various antinutritive effects in carnivorous fish. Exogenous enzymes have been shown to improve the apparent digestibility coefficients (ADC) of plant-based diets...... presumably by assisting in the breakdown of NSP. This study examined the effects on NSP degradation when supplementing β-glucanase, xylanase, protease or a mix of the three enzymes to an extruded, juvenile rainbow trout (Oncorhynchus mykiss) diet containing 344 g kg−1 de-hulled, solvent-extracted soybean...... meal (SBM). The NSP content in the non-supplemented control diet and in faecal samples from the dietary treatment groups was analysed to determine the recovery/apparent digestibility of cellulose and total non-cellulosic polysaccharide (T-NCP) sugar monomers. The enzymes had significant, positive...

  12. Previous bacterial infection affects textural quality parameters of heat-treated fillets from rainbow trout (Oncorhynchus mykiss)

    DEFF Research Database (Denmark)

    Ingerslev, Hans-Christian; Hyldig, Grethe; Przybylska, Dominika Alicja

    2012-01-01

    Sensory quality of fish meat is influenced by many parameters prior to slaughter. In the present study, it was examined if previous infections or damages in the muscle tissue influence product quality parameters in fish. Fillets from rainbow trout (Oncorhynchus mykiss) reared in seawater....... This article was the first to describe a correlation between previous infections in fish and changes in sensory-quality parameters. PRACTICAL APPLICATIONS. This work contributes with knowledge about sensory-quality parameters of fish meat after recovery from infections and physical-tissue damage. Because...... the results demonstrate an influence on the texture from previous disease, the practical potentials of the results are valuable for the aquaculture industry. In order to minimize the effects of previous diseases on the sensory quality regarding the texture, these fishes should be processed as cold...

  13. Host-derived probiotics Enterococcus casseliflavus improves resistance against Streptococcus iniae infection in rainbow trout (Oncorhynchus mykiss) via immunomodulation

    DEFF Research Database (Denmark)

    Safari, Reza; Adel, Milad; Lazado, Carlo Cabacang

    2016-01-01

    The present study evaluated the benefits of dietary administration of host-derived candidate probiotics Enterococcus casseliflavus in juvenile rainbow trout Oncorhynchus mykiss. Experimental diets were prepared by incorporating the microorganisms in the basal feed at 3 inclusion levels (i.e. 107...... CFU g-1 of feed [T1], 108 CFU g-1 of feed [T2], 109 CFU g-1 of feed [T3]). The probiotic feeds were administered for 8 weeks, with a group fed with the basal diet serving as control. The effects on growth performance, gut health, innate immunity and disease resistance were evaluated.Results showed...... that growth performance parameters were significantly improved in T2 and T3 groups. Activities of digestive enzymes such as trypsin and lipase were significantly higher in these two groups as well. Gut micro-ecology was influenced by probiotic feeding as shown by the significant increase in intestinal lactic...

  14. Effect of dietary Astaxanthin sources supplementation on muscle pigmentation and lipid peroxidation in rainbow trout (Oncorhynchus mykiss

    Directory of Open Access Journals (Sweden)

    Marco Saroglia

    2010-01-01

    Full Text Available Astaxanthin is one of the major carotenoids in aquatic animals including salmonid fishes and is the preferred pigments added to salmon feed. It’s also a powerful antioxidant compared to other carotenoids and that may confer numerous health benefits. The aim of the present experi- ment was to investigate the effect of Astaxanthin deposition on the lipids peroxidation by studying the Malondialdeide (MDA level in muscle of rainbow trout (Oncorhynchus mykiss. The Astaxanthin concentrations in fish fed with a commercial sources as Lucantin®Pink (BASF Ludwigshafen, Ger- many reached values to 5.76±0.18x10-3 mg/g after 50 days feeding, while the MDA concentration de- creased from 1.56x103 to 0.45x103 ng/g. The correlation between MDA and Astaxanthin concentrations decreased linearly and confirmed the antioxidant properties of the pigment by reducing the lipids peroxidation.

  15. Effects of excretory/secretory products from Anisakis simplex (Nematoda) on immune gene expression in rainbow trout (Oncorhynchus mykiss)

    DEFF Research Database (Denmark)

    Bahlool, Qusay Zuhair Mohammad; Skovgaard, Alf; Kania, Per Walter

    2013-01-01

    Excretory/secretory (ES) products are molecules produced by parasitic nematodes, including larval Anisakis simplex, a parasite occurring in numerous marine fish hosts. The effects of these substances on host physiology have not been fully described. The present work elucidates the influence of ES...... substances on the fish immune system by measuring immune gene expression in spleen and liver of rainbow trout (Oncorhynchus mykiss) injected intraperitoneally with ES products isolated from A. simplex third stage larvae. The overall gene expression profile of exposed fish showed a generalized down....... This type of hydrolytic enzyme activity may play a role in nematode penetration of host tissue. In addition, based on the notion that A. simplex ES products may have an immune-depressive effect (by minimizing immune gene expression) it could also be suggested that worm enzymes directly target host immune...

  16. Physico-chemical traits of raw and cooked fillets of rainbow trout (Oncorhynchus mykiss from different strains and farms

    Directory of Open Access Journals (Sweden)

    Roberta Martelli

    2014-09-01

    Full Text Available Fillets and cooking yields, water holding capacity, textural properties, colour, proximate composition, collagen and fatty acids of five strains (IT1, IT2, IT3, USA, UK of rainbow trout, Oncorhynchus mykiss, reared in three farms (F1, F2, F3, were measured before and after cooking. Physico-chemical parameters of the strains greatly differed both in raw and cooked state. IT2 and USA recorded the highest yields. IT2 distinguished from the other strains, showing lowest values of hardness, chewiness, gumminess and springiness. It also had brighter and less pigmented flesh with low fat, mainly in the raw state. USA strain showed the most valuable traits in terms of texture and colour, and had higher fat and collagen content in flesh. The physico-chemical profile of each strain was differently modified by cooking. USA strain maintained a positive texture and colour profile after cooking and its quality was the best.

  17. PAMP induced expression of immune relevant genes in head kidney leukocytes of rainbow trout (Oncorhynchus mykiss)

    DEFF Research Database (Denmark)

    Chettri, Jiwan Kumar; Raida, Martin Kristian; Holten-Andersen, Lars

    2011-01-01

    ) on the surface of the invader. Phagocytic cells are known to initiate a respiratory burst following an exposure to the pathogen, but the underlying and associated specific elements are poorly elucidated in fish. The present study describes the differential response of head kidney leukocytes from rainbow trout...... (Oncorhynchus mykiss) to different PAMPs mimicking viral (poly I:C), bacterial (flagellin and LPS) and fungal infections (zymosan and ß-glucan). Transcript of cytokines related to inflammation (IL-1ß, IL-6, IL-10 and TNF-a) was highly up-regulated following LPS exposure whereas flagellin or poly I:C induced...... merely moderate reactions. In contrast, IFN-¿ expression was significantly higher in the poly I:C stimulated group compared to the LPS group. When head kidney cells were exposed to zymosan or ß-glucan, genes encoding IL-1ß, TNF-a, IL-6 and IL-10 became up-regulated. Their level of up...

  18. Protein level affects the relative lysine requirement of growing rainbow trout (Oncorhynchus mykiss) fry.

    Science.gov (United States)

    Bodin, Noelie; Govaerts, Bernadette; Abboudi, Tarik; Detavernier, Christel; De Saeger, Sarah; Larondelle, Yvan; Rollin, Xavier

    2009-07-01

    The effect of two digestible protein levels (310 and 469 g/kg DM) on the relative lysine (Lys; g Lys/kg DM or g Lys/100 g protein) and the absolute Lys (g Lys intake/kg 0.75 per d) requirements was studied in rainbow trout fry using a dose-response trial. At each protein level, sixteen isoenergetic (22-23 MJ digestible energy/kg DM) diets were tested, involving a full range (2-70 g/kg DM) of sixteen Lys levels. Each diet was given to one group of sixty rainbow trout fry (mean initial body weight 0.78 g) reared at 15 degrees C for 31 feeding d. The Lys requirements were estimated based on the relationships between weight, protein, and Lys gains (g/kg 0.75 per d) and Lys concentration (g/kg DM or g/100 g protein) or Lys intake (g/kg 0.75 per d), using the broken-line model (BLM) and the non-linear four-parameter saturation kinetics model (SKM-4). Both the model and the response criterion chosen markedly impacted the relative Lys requirement. The relative Lys requirement for Lys gain of rainbow trout estimated with the BLM (and SKM-4 at 90 % of the maximum response) increased from 16.8 (19.6) g/kg DM at a low protein level to 23.4 (24.5) g/kg DM at a high protein level. However, the dietary protein content affected neither the absolute Lys requirement nor the relative Lys requirement expressed as g Lys/100 g protein nor the Lys requirement for maintenance (21 mg Lys/kg 0.75 per d).

  19. Effects of chronic high stocking density on liver proteome of rainbow trout (Oncorhynchus mykiss).

    Science.gov (United States)

    Naderi, Mahdi; Keyvanshokooh, Saeed; Salati, Amir Parviz; Ghaedi, Alireza

    2017-10-01

    The main aim of the present study was to assess the effects of chronic high stocking density on liver proteome of rainbow trout. Rainbow trout juveniles (42.6 ± 2.3 g average body weight) were randomly distributed into six tanks at two stocking densities (low stocking density (LD) = 20 kg m -3 and high stocking density (HD) = 80 kg m -3 ). Both treatments were performed in triplicate tanks for a period of 60 days. High stocking density caused a reduction in the growth performance compared with LD fish. Lysozyme activity increased with stocking density, while serum complement activity presented the opposite pattern. Serum cortisol and total protein levels did not show significant differences (P > 0.05) between experimental groups. The fish reared at high stocking density showed significantly lower osmolality and globulin values but higher albumin level. The HD group had significantly higher activities of catalase, glutathione peroxidase and superoxide dismutase, and malondialdehyde content in the liver when compared to the LD group. Comparative proteomics was used to determine the proteomic responses in livers of rainbow trout reared at high stocking density for 60 days. Out of nine protein spots showing altered abundance (>1.5-folds, P < 0.05), eight spots were successfully identified. Two proteins including apolipoprotein A-I-2 precursor and mitochondrial stress-70 protein were found to increase in HD group. The spots found to decrease in the HD group were identified as follows: 2-peptidylprolyl isomerase A, two isoforms of glyceraldehydes-3-phosphate dehydrogenase, an unnamed protein product similar to fructose-bisphosphate aldolase, 78 kDa glucose-regulated protein, and serum albumin 1 protein.

  20. Influence of dietary recombinant microbial lipase on performance and quality characteristics of rainbow trout, Oncorhynchus mykiss

    DEFF Research Database (Denmark)

    Samuelsen, Troels; Isaksen, Mai; McLean, Ewen

    2001-01-01

    In order to assess whether supplementary lipase affected growth and body composition of trout, four diets were produced, consisting of (A) feed containing high (2083 mg kg(-1)), (B) low (208.3 mg kg(-1)) concentrations of lipase, (C) heat-treated (inactivated) lipase (2083 mg kg(-1)), and (D......) a basal control diet. Rainbow trout (n = 40/tank; initial wt. 23.22 +/- 4.81 g; length 124.7 +/- 6.35 mm) were fed, according to commercial feed tables, 6 days/week for 202 days. Retained activity of supplemental lipase was verified by monitoring free fatty acid appearance (FAA), which was significantly...... higher(P Lipase addition had no effect(P > 0.05) on growth, fillet proximate composition, hepatosomatic, cardiac, or gut indices, and carcass percentage. However, lipase supplementation influenced the mono-unsaturated fatty acid profiles of the fillet (P

  1. Cortisol regulates nitric oxide synthase in freshwater and seawater acclimated rainbow trout, Oncorhynchus mykiss

    DEFF Research Database (Denmark)

    Gerber, Lucie; Madsen, Steffen S; Jensen, Frank B

    2017-01-01

    Cortisol and nitric oxide (NO) are regulators of ion transport and metabolic functions in fish. In the gill, they show opposite effects on Na(+)/K(+)-ATPase (NKA) activity: cortisol stimulates NKA activity while NO inhibits NKA activity. We hypothesized that cortisol may impact NO production...... in osmoregulatory tissues by regulating NO synthase (NOS) expression. We evaluated the influence of cortisol treatment on mRNA expression of Nos1 and Nos2 in gill, kidney and middle intestine of both freshwater (FW) and seawater (SW) acclimated rainbow trout and found both tissue- and salinity-dependent effects....... Nos2 expression was down-regulated in the gill by cortisol injection in both FW and SW trout. This was substantiated by incubating gill tissue with cortisol ex vivo. Similarly, cortisol injection significantly down-regulated Nos2 expression in kidney of SW fish but not in FW fish. In the middle...

  2. Oil adjuvant elevates protection of rainbow trout (Oncorhynchus my-kiss) following injection vaccination against Yersinia ruckeri

    DEFF Research Database (Denmark)

    Jaafar, Rzgar M.; Chettri, Jiwan Kumar; Dalsgaard, Inger

    2016-01-01

    Enteric redmouth disease (ERM) caused by the fish pathogen Yersinia ruckeri is a major threat to freshwater production of rainbow trout throughout all life stages. Injection vaccination of rainbow trout against Y. ruckeri infection has been shown to confer better protection compared to the tradit...

  3. Evaluation of potential sources of proteins in diets for rainbow trout (Oncorhynchus mykiss).

    Science.gov (United States)

    Pfeffer, E; Henrichfreise, B

    1994-01-01

    7 diets were prepared containing as their only source of protein one of the following feeds: fish meal, casein, hydrolyzed feather meal, grieves, wheat gluten, maize gluten, soybean meal. Crystalline amino acids were supplemented except in cases of fish meal and casein to prevent specific amino acid deficiencies. Concentrations of N x 6.25 ranged between 436 and 457 g/kg dry matter (DM). Cr2O3 was added to each diet for indirect determination of digestibilities. Each diet was fed to triplicate groups of 20 rainbow trout of an average initial weight of 60 g. After 66 feeding days, all trout were killed and used for whole body analyses. Due to severely reduced intake, trout fed the casein based diet gained only about half as much weight as trout fed the fish meal based diet, though at the same fed conversion ratio of 1.0 kg gain per kg dietary DM. Gains on the other diets ranged between these two treatments with poorer feed conversion ratios. Digestibilities of crude protein of fish meal, casein, hydrolyzed feather meal, grieves, wheat gluten, maize gluten and soybean meal were: 86, 98, 67, 81, 97, 87, and 94%, respectively. The corresponding contents of digestible energy were: 21.2, 21.8, 15.4, 16.5, 19.6, 18.3, and 14.4 Mj/kg DM. Efficiency of utilization of digestible energy ranged between 43 and 54%, that of digestible crude protein between 32 and 41%.

  4. New insights into the nutritional regulation of gluconeogenesis in carnivorous rainbow trout (Oncorhynchus mykiss): a gene duplication trail.

    Science.gov (United States)

    Marandel, Lucie; Seiliez, Iban; Véron, Vincent; Skiba-Cassy, Sandrine; Panserat, Stéphane

    2015-07-01

    The rainbow trout (Oncorhynchus mykiss) is considered to be a strictly carnivorous fish species that is metabolically adapted for high catabolism of proteins and low utilization of dietary carbohydrates. This species consequently has a "glucose-intolerant" phenotype manifested by persistent hyperglycemia when fed a high-carbohydrate diet. Gluconeogenesis in adult fish is also poorly, if ever, regulated by carbohydrates, suggesting that this metabolic pathway is involved in this specific phenotype. In this study, we hypothesized that the fate of duplicated genes after the salmonid-specific 4th whole genome duplication (Ss4R) may have led to adaptive innovation and that their study might provide new elements to enhance our understanding of gluconeogenesis and poor dietary carbohydrate use in this species. Our evolutionary analysis of gluconeogenic genes revealed that pck1, pck2, fbp1a, and g6pca were retained as singletons after Ss4r, while g6pcb1, g6pcb2, and fbp1b ohnolog pairs were maintained. For all genes, duplication may have led to sub- or neofunctionalization. Expression profiles suggest that the gluconeogenesis pathway remained active in trout fed a no-carbohydrate diet. When trout were fed a high-carbohydrate diet (30%), most of the gluconeogenic genes were non- or downregulated, except for g6pbc2 ohnologs, whose RNA levels were surprisingly increased. This study demonstrates that Ss4R in trout involved adaptive innovation via gene duplication and via the outcome of the resulting ohnologs. Indeed, maintenance of ohnologous g6pcb2 pair may contribute in a significant way to the glucose-intolerant phenotype of trout and may partially explain its poor use of dietary carbohydrates. Copyright © 2015 the American Physiological Society.

  5. Boule gene expression underpins the meiotic arrest in spermatogenesis in male rainbow trout (Oncorhynchus mykiss) exposed to DEHP and butachlor.

    Science.gov (United States)

    Ahmadivand, Sohrab; Farahmand, Hamid; Teimoori-Toolabi, Ladan; Mirvaghefi, Alireza; Eagderi, Soheil; Geerinckx, Tom; Shokrpoor, Sara; Rahmati-Holasoo, Hooman

    2016-01-01

    Boule, the ancestor of the DAZ (Deleted in AZoospermia) gene family, in most organisms is mainly involved in male meiosis. The present study investigates the effects of the plasticizer DEHP (50mg/kg body weight) and herbicide butachlor (0.39mg/L) on male rainbow trout (Oncorhynchus mykiss) for a 10-day period in two independent experiments. The results showed that plasma testosterone (T) concentrations were significantly lower in fish exposed to either DEHP or butachlor compared to the control fish (P0.05). In addition, no significant differences were found in the gonadosomatic index (GSI) in both DEHP and butachlor treatments (P>0.05). Histologically, testes of male trout in the control groups were well differentiated and filled with large numbers of cystic structures containing spermatozoa. In contrast, the testes of male trout contained mostly spermatocytes with few spermatozoa in both treated group, suggesting that DEHP and butachlor may inhibit the progression of meiosis. Also, boule gene expression was significantly lower in the testes of male trout affected by DEHP and butachlor in comparison with their control groups (Ptrout. Based on the results, the present study demonstrated that DEHP and butachlor can inhibit the progression of spermatogenesis in male trout, potentially by causing an arrest of meiosis, maybe due to down-regulation of boule gene expression through T and/or IGF1 via ERK1/2 signaling in T-independent pathways. In addition, these results confirmed that boule can be considered as a predictive marker to assess meiotic efficiency. Copyright © 2015 Elsevier Inc. All rights reserved.

  6. TheInfluence of Extruded Feed with a high Protein Level Upon the Bioproductive Performances Obtained on the Rainbow Trout Females (Oncorhynchus mykiss

    Directory of Open Access Journals (Sweden)

    Mihaela Ancuta Boaru

    2016-11-01

    Full Text Available The succes ofartificial reproduction in the rainbow trout(Oncorhynchus mykiss, the development of gonads and the results obtained at incubation are significantly affected by the feeding of the breeders. The use of quality sexual  products is decisive for the assurance of the production of viable larvae and further of the estimated fish production, so that in addition to the assurance of optimal environmental parameters, the proper feeding of the breeders is required. Starting from the current stage of knowledge in the field,the main objective of the working paperwas to highlight the way the differentiatedfeeding of the rainbow trout females (Oncorhynchus mykiss influences their growth and development. The extruded peeled feed with a high protein level upon theegg weightand the gonosomatic index were followed. The extruded peeled feed with 53% protein proved to be highly effective, materialized trough high growth performances, a better conversion and the growth of gonadal  weight.

  7. Mycotoxigenic fungi and natural co-occurrence of mycotoxins in rainbow trout (Oncorhynchus mykiss) feeds.

    Science.gov (United States)

    Greco, Mariana; Pardo, Alejandro; Pose, Graciela

    2015-11-05

    Samples of rainbow trout feed were analyzed with the aim to determine the mycobiota composition and the co-occurrence of mycotoxins. A total of 28 samples of finished rainbow trout feed from hatcheries in the provinces of Río Negro and Neuquén, Argentina, were studied. Fungal counts were obtained on three culture media in the ranges of Aspergillus (Fr 3.6%). The most prevalent mycotoxigenic species were E. repens (Fr 21.4%) and E. rubrum (Fr 14.3%). All samples were contaminated with mycotoxins: 64% samples were contaminated with T-2 toxin (median 70.08 ppb), 50% samples with zearalenone (median 87.97 ppb) and aflatoxins (median 2.82 ppb), 25% with ochratoxin A (median 5.26 ppb) and 3.57% samples with deoxynivalenol (median 230 ppb). Eight samples had a fumonisins contamination level below the limit of detection. Co-occurrence of six mycotoxins was determined in 7% of the samples.

  8. Mycotoxigenic Fungi and Natural Co-Occurrence of Mycotoxins in Rainbow Trout (Oncorhynchus mykiss Feeds

    Directory of Open Access Journals (Sweden)

    Mariana Greco

    2015-11-01

    Full Text Available Samples of rainbow trout feed were analyzed with the aim to determine the mycobiota composition and the co-occurrence of mycotoxins. A total of 28 samples of finished rainbow trout feed from hatcheries in the provinces of Río Negro and Neuquén, Argentina, were studied. Fungal counts were obtained on three culture media in the ranges of <10 to 4.2 × 104 CFU/g on Dichloran Rose Bengal Chloramphenicol Agar (DRBC, <10 to 5.1 × 104 CFU/g on Dichloran Chloramphenicol Peptone Agar (DCPA and <10 to 3.6 × 104 CFU/g on Dichloran 18% Glycerol Agar (DG18. The most frequent mycotoxigenic fungi were Eurotium (frequency (Fr 25.0%, followed by Penicillium (Fr 21.4% and Aspergillus (Fr 3.6%. The most prevalent mycotoxigenic species were E. repens (Fr 21.4% and E. rubrum (Fr 14.3%. All samples were contaminated with mycotoxins: 64% samples were contaminated with T-2 toxin (median 70.08 ppb, 50% samples with zearalenone (median 87.97 ppb and aflatoxins (median 2.82 ppb, 25% with ochratoxin A (median 5.26 ppb and 3.57% samples with deoxynivalenol (median 230 ppb. Eight samples had a fumonisins contamination level below the limit of detection. Co-occurrence of six mycotoxins was determined in 7% of the samples.

  9. Temporal Genetic Variance and Propagule-Driven Genetic Structure Characterize Naturalized Rainbow Trout (Oncorhynchus mykiss) from a Patagonian Lake Impacted by Trout Farming.

    Science.gov (United States)

    Benavente, Javiera N; Seeb, Lisa W; Seeb, James E; Arismendi, Ivan; Hernández, Cristián E; Gajardo, Gonzalo; Galleguillos, Ricardo; Cádiz, Maria I; Musleh, Selim S; Gomez-Uchida, Daniel

    2015-01-01

    Knowledge about the genetic underpinnings of invasions-a theme addressed by invasion genetics as a discipline-is still scarce amid well documented ecological impacts of non-native species on ecosystems of Patagonia in South America. One of the most invasive species in Patagonia's freshwater systems and elsewhere is rainbow trout (Oncorhynchus mykiss). This species was introduced to Chile during the early twentieth century for stocking and promoting recreational fishing; during the late twentieth century was reintroduced for farming purposes and is now naturalized. We used population- and individual-based inference from single nucleotide polymorphisms (SNPs) to illuminate three objectives related to the establishment and naturalization of Rainbow Trout in Lake Llanquihue. This lake has been intensively used for trout farming during the last three decades. Our results emanate from samples collected from five inlet streams over two seasons, winter and spring. First, we found that significant intra- population (temporal) genetic variance was greater than inter-population (spatial) genetic variance, downplaying the importance of spatial divergence during the process of naturalization. Allele frequency differences between cohorts, consistent with variation in fish length between spring and winter collections, might explain temporal genetic differences. Second, individual-based Bayesian clustering suggested that genetic structure within Lake Llanquihue was largely driven by putative farm propagules found at one single stream during spring, but not in winter. This suggests that farm broodstock might migrate upstream to breed during spring at that particular stream. It is unclear whether interbreeding has occurred between "pure" naturalized and farm trout in this and other streams. Third, estimates of the annual number of breeders (Nb) were below 73 in half of the collections, suggestive of genetically small and recently founded populations that might experience substantial

  10. Effects of Gelatin-Based Edible Films Enriched with Laurel Essential Oil on the Quality of Rainbow Trout (Oncorhynchus mykiss) Fillets During Refrigerated Storage

    OpenAIRE

    Tuba Baygar; Taçnur Baygar; Hatice Hasanhocaoglu; Cansu Metin; Yunus Alparslan

    2014-01-01

    The effects of gelatin films enriched with laurel leaf essential oil on the quality of rainbow trout (Oncorhynchus mykiss) during refrigerated storage at (4±1) °C were examined over a period of 26 days. Fish fillets were wrapped with 8 % gelatin films containing 0, 0.1 and 1 % (by volume per mass) of laurel essential oil and vacuum packaged. Sensory (raw and cooked fish), microbiological (total viable counts, psychrotrophic bacteria counts, Enterobacteriaceae and lactic acid bacteria) and ...

  11. Comparison of plasma and tissue disposition of enrofloxacin in rainbow trout (Oncorhynchus mykiss) and common carp (Cyprinus carpio) after a single oral administration.

    Science.gov (United States)

    Kyuchukova, Ralica; Milanova, Aneliya; Pavlov, Alexander; Lashev, Lubomir

    2015-01-01

    The aim of the study was to investigate the serum and tissue disposition of enrofloxacin and its active metabolite ciprofloxacin in rainbow trout (Oncorhynchus mykiss) and common carp (Cyprinus carpio) after a single oral administration at a dose of 10 mg kg(-1). Concentrations of enrofloxacin in the serum of rainbow trout showed high variability with two peaks at the third and 24th hour after administration. The highest concentrations were found in the liver. The curves of liver levels showed similar changes to the respective serum samples. In the muscles, enrofloxacin concentrations were also higher compared with the respective serum samples. Ciprofloxacin concentrations were lower and showed smaller variations in all investigated tissues. The serum and tissue concentrations of enrofloxacin and ciprofloxacin in common carp showed two peaks, with the first Cmax at the third hour after drug administration as in rainbow trout. Concentrations of both investigated substances were higher in the liver than in the serum. The differences in common carp were less pronounced in comparison with rainbow trout. Relatively high levels of both substances were found in the muscles. Seven days after treatment enrofloxacin concentrations in the serum and tissues were within the therapeutic levels for most of the sensitive microorganisms in trout. Lower concentrations of its metabolite ciprofloxacin were found in the investigated tissues at the last sampling point. Lower levels of both substances were found in carp.

  12. Effect of Exposure Dose on Ichthyophonus Prevalence and Infection Intensity in Experimentally Infected Rainbow Trout, Oncorhynchus mykiss.

    Science.gov (United States)

    Kocan, Richard; LaPatra, Scott

    2016-02-01

    This study describes the effect of increasing exposure dose on Ichthyophonus prevalence and infection intensity in experimentally infected rainbow trout, Oncorhynchus mykiss. Specific-pathogen free trout were exposed per os to increasing numbers of Ichthyophonus schizonts obtained from naturally infected donor fish, then sampled after 30 and 60 days post-exposure. Both in vitro explant culture and histology revealed that as the number of schizonts per dose increased there was a proportionate increase in the number of infected fish, as well as an increase in the number of infected organs; parasite density in individual infected organs also increased with dose. Explant culture revealed that all fish exposed to the highest dose (≥2,080 schizonts) became infected, while only 67% of those exposed to the intermediate dose (1,040-1,153 schizonts) were Ichthyophonus-positive after 60 days; Ichthyophonus was not detected in fish exposed to the 2 lowest doses (≤280 schizonts). Histologic examination of individual infected organs also revealed increasing infection prevalence and parasite density in response to exposure to increasing numbers of Ichthyophonus schizonts.

  13. A putative serine protease, SpSsp1, from Saprolegnia parasitica is recognised by sera of rainbow trout, Oncorhynchus mykiss

    Science.gov (United States)

    Minor, Kirsty L.; Anderson, Victoria L.; Davis, Katie S.; Van Den Berg, Albert H.; Christie, James S.; Löbach, Lars; Faruk, Ali Reza; Wawra, Stephan; Secombes, Chris J.; Van West, Pieter

    2014-01-01

    Saprolegniosis, the disease caused by Saprolegnia sp., results in considerable economic losses in aquaculture. Current control methods are inadequate, as they are either largely ineffective or present environmental and fish health concerns. Vaccination of fish presents an attractive alternative to these control methods. Therefore we set out to identify suitable antigens that could help generate a fish vaccine against Saprolegnia parasitica. Unexpectedly, antibodies against S. parasitica were found in serum from healthy rainbow trout, Oncorhynchus mykiss. The antibodies detected a single band in secreted proteins that were run on a one-dimensional SDS-polyacrylamide gel, which corresponded to two protein spots on a two-dimensional gel. The proteins were analysed by liquid chromatography tandem mass spectrometry. Mascot and bioinformatic analysis resulted in the identification of a single secreted protein, SpSsp1, of 481 amino acid residues, containing a subtilisin domain. Expression analysis demonstrated that SpSsp1 is highly expressed in all tested mycelial stages of S. parasitica. Investigation of other non-infected trout from several fish farms in the United Kingdom showed similar activity in their sera towards SpSsp1. Several fish that had no visible saprolegniosis showed an antibody response towards SpSsp1 suggesting that SpSsp1 might be a useful candidate for future vaccination trial experiments. PMID:25088077

  14. Flavobacterium plurextorum sp. nov. Isolated from Farmed Rainbow Trout (Oncorhynchus mykiss)

    OpenAIRE

    Zamora, Leydis; Fern?ndez-Garayz?bal, Jos? F.; S?nchez-Porro, Cristina; Palacios, Mari Angel; Moore, Edward R. B.; Dom?nguez, Lucas; Ventosa, Antonio; Vela, Ana I.

    2013-01-01

    Five strains (1126-1H-08(T), 51B-09, 986-08, 1084B-08 and 424-08) were isolated from diseased rainbow trout. Cells were Gram-negative rods, 0.7 µm wide and 3 µm long, non-endospore-forming, catalase and oxidase positive. Colonies were circular, yellow-pigmented, smooth and entire on TGE agar after 72 hours incubation at 25°C. They grew in a temperature range between 15°C to 30°C, but they did not grow at 37°Cor 42°C. Based on 16S rRNA gene sequence analysis, the isolates belonged to the genus...

  15. Effects of water chemistry and temperature on radiocesium dynamics in rainbow trout, Oncorhynchus mykiss

    Energy Technology Data Exchange (ETDEWEB)

    Cocchio, L. A.; Beamish, F. W. H. [Guelph Univ., ON (Canada); Rodgers, D. W. [Ontario Hydro Technologies, Natural Sciences, Toronto, ON (Canada)

    1995-03-01

    Cesium-137 ({sup 137}Cs) is of particular concern among radionuclides because of high yield in uranium-235 fission, its relatively long half-life (30 years) and its tendency to accumulate in aquatic biota. Effect of potassium ion (K{sup +}) concentration on {sup 137}Cs accumulation in rainbow trout were examined. The first set of experiments determined the effects of temperature and K{sup +} on the elimination of dietary {sup 137}Cs. The effects of the uptake and elimination of {sup 137}Cs over a wider range of K{sup +} concentrations was also studied and the effects of Na{sup +} and Ca{sup 2+} were examined because their concentrations were affected by concentrations of K{sup +}. Elimination of {sup 137}Cs was heavily affected by the concentration of K{sup +} and temperature, although uptake was independent of these factors. Cs elimination appeared to be a function of metabolic rate. 1 tab., 3 figs., 35 refs.

  16. Estrogenic effect of propylparaben (propylhydroxybenzoate) in rainbow trout Oncorhynchus mykiss after exposure via food and water

    DEFF Research Database (Denmark)

    Bjerregaard, Poul; Andersen, Dorthe N; Pedersen, Knud L

    2003-01-01

    l(-1) for 12 days. Plasma vitellogenin was measured before and during the exposures and the concentrations of propylparaben in liver and muscle were determined at the end of experiments. Increases in average plasma vitellogenin levels were seen at oral exposure to 33 mg propylparabenkg(-1) 2 d(-1......); the most sensitive fish responded to 7 mg kg(-1). The ED(50) values for increase in vitellogenin synthesis were 35, 31 and 22 mg kg(-1) 2 d(-1) at day 3, 6 and 11, respectively. Exposure to 225 microg propylparabenl(-1) increased vitellogenin synthesis, but exposure to 50 microg l(-1) did not....... Propylparaben showed little tendency to bioaccumulation in rainbow trout; less than 1 per thousand of the total amount of propylparaben administered orally at 1830 mg kg(-1) 2 d(-1) over the 10-d experimental period was retained in muscle and liver 24 h after the end of the experiment. Exposure to 225 microg...

  17. Challenge studies of European stocks of redfin perch, Perca fluviatilis L., and rainbow trout, Oncorhynchus mykiss (Walbaum), with epizootic haematopoietic necrosis virus

    DEFF Research Database (Denmark)

    Ariel, Ellen; Jensen, Ann Britt Bang

    2009-01-01

    indicate that EHNV does not pose a high risk for wild perch and trout populations in Europe by natural exposure. Mortality appears to be primarily a function of environmental factors, with temperature playing an important role, and not just the presence of the virus in the fish.......A challenge model for comparison of the virulence of epizootic haematopoietic necrosis virus (EHNV) to European stock of redfin perch, Perca fluviatilis L., and rainbow trout, Oncorhynchus mykiss (Walbaum), was tested. The model investigated intraperitoneal (IP), bath and cohabitation routes at 10...

  18. Antimicrobial peptide CAP18 and its effect on Yersinia ruckeri infections in rainbow trout Oncorhynchus mykiss (Walbaum): comparing administration by injection and oral routes

    DEFF Research Database (Denmark)

    Chettri, Jiwan Kumar; Mehrdana, F.; Hansen, Egon Bech

    2017-01-01

    The antimicrobial peptide CAP18 has been demonstrated to have a strong in vitro bactericidal effect on Yersinia ruckeri, but its activity in vivo has not been described. In this work, we investigated whether CAP18 protects rainbow trout Oncorhynchus mykiss (Walbaum) against enteric red mouth...... the conventional antibiotic oxolinic acid. Oral administration of CAP18 to trout did not prevent infection. The proteolytic effect of secretions on the peptide CAP18 in the fish gastrointestinal tract is suggested to account for the inferior effect of oral administration....

  19. ASSESSMENT OF MAXIMUM SUSTAINABLE SWIMMING PERFORMANCE IN RAINBOW TROUT (ONCORHYNCHUS MYKISS)

    Science.gov (United States)

    Wilson; Egginton

    1994-07-01

    Levels of swimming activity in fishes have been divided into three categories on the basis of the time a given speed can be maintained before the onset of fatigue (Beamish, 1978): sustained (more than 200 min), prolonged (20 s to 200 min) and burst swimming (less than 20 s). The locomotory capacity of a given species reflects both its lifestyle and its body form, although definitions of performance may vary. It is generally accepted that only the aerobic ('red') muscle fibres should be active at truly sustainable swimming speeds, i.e. at speeds that can be maintained indefinitely without fatigue. However, the standard laboratory method of evaluating the maximum sustainable swimming speed (Ucrit; Brett, 1964) almost certainly entails the recruitment of at least some of the rapidly fatigable fast glycolytic ('white') fibres at sub-critical speeds and undoubtedly complicates the evaluation of maximal cardiovascular performance. It would therefore be useful to have an objective and reproducible measure of truly sustainable performance that, by definition, relies solely on aerobic muscle activity. Electromyography (EMG) has been used to examine the pattern of white muscle recruitment following thermal acclimation in striped bass, Morine saxatilis (Sisson and Sidell, 1987). We wished to incorporate this method into a study of the acclimatory responses to chronic changes in environmental temperature of the cardiovascular and locomotory systems in rainbow trout (Wilson and Egginton, 1992). The present communication presents results on the cardiovascular performance and blood chemistry, at rest and during maximal aerobic exercise, of rainbow trout acclimated to 11 °C, as a validation of the methodology currently in use with fish acclimated to seasonal temperature extremes (Taylor et al. 1992). Different acclimation temperatures are known to produce compensatory changes in the relative proportions of red and white muscle mass (Sidell and Moerland, 1989). The aim of these

  20. Characterization of Pediococcus acidilactici strains isolated from rainbow trout (Oncorhynchus mykiss) feed and larvae: safety, DNA fingerprinting, and bacteriocinogenicity.

    Science.gov (United States)

    Araújo, Carlos; Muñoz-Atienza, Estefanía; Poeta, Patrícia; Igrejas, Gilberto; Hernández, Pablo E; Herranz, Carmen; Cintas, Luis M

    2016-05-03

    The use of lactic acid bacteria (LAB) as probiotics constitutes an alternative or complementary strategy to chemotherapy and vaccination for disease control in aquaculture. The objectives of this work were (1) the in vitro safety assessment of 8 Pediococcus acidilactici strains isolated from rainbow trout (Oncorhynchus mykiss, Walbaum) feed and larvae; (2) the evaluation of their genetic relatedness; (3) the study of their antimicrobial/bacteriocin activity against fish pathogens; and (4) the biochemical and genetic characterization of the bacteriocin produced by the strain displaying the greatest antimicrobial activity. Concerning the safety assessment, none of the pediococci showed antibiotic resistance nor produced hemolysin or gelatinase, degraded gastric mucin, or deconjugated bile salts. Four strains (50%) produced tyramine or putrescine, but the corresponding genes were not amplified by PCR. Enterobacterial repetitive intergenic consensus-PCR (ERIC-PCR) fingerprinting allowed clustering of the pediococci into 2 well-defined groups (68% similarity). From the 8 pediococci displaying direct antimicrobial activity against at least 3 out of 9 fish pathogens, 6 strains (75%) were identified as bacteriocin producers. The bacteriocin produced by P. acidilactici L-14 was purified, and mass spectrometry and DNA sequencing revealed its identity to pediocin PA-1 (PedPA-1). Altogether, our results allowed the identification of 4 (50%) putatively safe pediococci, including 2 bacteriocinogenic strains. ERIC-PCR fingerprinting was a valuable tool for genetic profiling of P. acidilactici strains. This work reports for the first time the characterization of a PedPA-1-producing P. acidilactici strain isolated from an aquatic environment (rainbow trout larvae), which shows interesting properties related to its potential use as a probiotic in aquaculture.

  1. Consecutive emamectin benzoate and deltamethrin treatments affect the expressions and activities of detoxification enzymes in the rainbow trout (Oncorhynchus mykiss).

    Science.gov (United States)

    Cárcamo, Juan Guillermo; Aguilar, Marcelo N; Carreño, Constanza F; Vera, Tamara; Arias-Darraz, Luis; Figueroa, Jaime E; Romero, Alex P; Alvarez, Marco; Yañez, Alejandro J

    2017-01-01

    Rainbow trout (Oncorhynchus mykiss) subjected to three consecutive, alternating treatments with emamectin benzoate (EMB) and deltamethrin (DM) during outbreaks of Caligus rogercresseyi in a farm located in southern Chile (Hornopiren, Chiloé), were studied to determine the effects of these treatments on the protein and enzymatic activity levels of cytochrome P450 1A (CYP1A), flavin-containing monooxygenase (FMO) and glutathione S-transferase (GST) in different tissues. Consecutive and alternating EMB/DM treatments resulted in a 10-fold increase and 3-fold decrease of CYP1A protein levels in the intestine and gills, respectively. Notably, CYP1A activity levels decreased in most of the analyzed tissues. FMO protein and activity levels markedly increased in the kidney and the intestine. GST was up-regulated in all tissues, either as protein or enzyme activity. When comparing consecutive EMB/DM treatments against previous studies of EMB treatment alone, CYP1A activity levels were similarly diminished, except in muscle. Likewise, FMO activity levels were increased in most of the analyzed tissues, particularly in the muscle, kidney, and intestine. The increases observed for GST were essentially unchanged between consecutive EMB/DM and EMB only treatments. These results indicate that consecutive EMB/DM treatments in rainbow trout induce the expression and activity of FMO and GST enzymes and decrease CYP1A activity. These altered activities of detoxification enzymes could generate imbalances in metabolic processes, synthesis, degradation of hormones and complications associated with drug interactions. It is especially important when analyzing possible effects of consecutive antiparasitic treatments on withholding periods and salmon farming yields. Copyright © 2016 Elsevier Inc. All rights reserved.

  2. In vitro characterization of cadmium transport along the gastro-intestinal tract of freshwater rainbow trout (Oncorhynchus mykiss)

    Energy Technology Data Exchange (ETDEWEB)

    Klinck, Joel S., E-mail: klinckjs@mcmaster.ca [Department of Biology, McMaster University, Hamilton, Ontario, L8S 4K1 (Canada); Wood, Chris M. [Department of Biology, McMaster University, Hamilton, Ontario, L8S 4K1 (Canada)

    2011-03-15

    An in vitro gut sac technique was used to examine the mechanism(s) of cadmium (Cd) uptake along the gastro-intestinal tract (GIT) of rainbow trout (Oncorhynchus mykiss). The spatial distribution of Cd between three compartments (mucus-binding, mucosal epithelium, and transport into blood space) was determined using a modified Cortland saline containing 50 {mu}M Cd (as CdCl{sub 2}) labeled with {sup 109}Cd radiotracer. Taking into account total surface areas, the order of relative importance for total Cd uptake rate was: posterior intestine > anterior intestine > stomach > mid intestine. Cd transport was not inhibited by experimentally reducing fluid transport rates by manipulation of osmotic gradients using mannitol, but was sensitive to internal luminal pressure changes, suggesting a mechanosensitive pathway. Q{sub 10} values (1, 11, and 19 {sup o}C) indicated a facilitated transport of Cd in the anterior- and mid-intestine. The effects of 10 mM Ca on the kinetics of Cd uptake suggest the presence of a common uptake pathway for Cd and Ca in the stomach, anterior-, and mid-intestine. Further evidence of a shared route of entry was found using three Ca channel blockers, lanthanum, verapamil, and nifedipine: both voltage-insensitive and voltage-sensitive Ca channels appear to be present in either some, or all portions of the GIT. Elevated Fe (500 {mu}M), Mg (50 mM), and Zn (500 {mu}M) showed varying degrees of inhibition of Cd transport depending on the compartment and segment of the GIT. Overall it appears that there are multiple sites, and mechanisms, of Cd uptake along the GIT of rainbow trout.

  3. Short-term responses of selected endocrine parameters in juvenile rainbow trout (Oncorhynchus mykiss) exposed to 4-nonylphenol.

    Science.gov (United States)

    Naderi, Mohammad; Zargham, Davood; Asadi, Asad; Bashti, Tayebeh; Kamayi, Kianoosh

    2015-12-01

    The synthetic organic compound 4-nonylphenol (4-NP) has been shown to have a wide range of adverse effects on the endocrine system of various animals including fish. The present study evaluated the potential effects of 4-NP on vitellogenin (VTG) synthesis, steroid, and thyroid hormone concentrations in both juvenile male and female rainbow trout (Oncorhynchus mykiss). Fish were exposed by intraperitoneal injection to different doses of 4-NP (1, 10, 50, and 100 μg g(-1)) or vehicle (coconut oil) over a period of 14 days. Blood samples were collected 7 and 14 days after initiation of treatment. Plasma VTG levels in 4-NP-treated fish were detected by sodium dodecyl sulfate polyacrylamide gel electrophoresis as a high molecular weight protein band of 180 KDa. In addition, plasma VTG concentrations were quantified indirectly using plasma alkali-labile phosphate (ALP) and plasma calcium. Both ALP and calcium levels in plasma showed similar and parallel increase patterns after exposure to 4-NP that were significantly higher compared with controls. The analysis of plasma sex steroid levels revealed a significant increase in 17β-estradiol and testosterone in plasma of juvenile males and females, respectively. Furthermore, a significant increase was observed in plasma cortisol levels. On the other hand, 4-NP decreased both plasma triiodothyronine and thyroxine after 7 and 14 days of treatment. These results suggest that 4-NP can affect different parts of the endocrine system, which may lead to serious impairments in physiological homeostasis of juvenile rainbow trout. © The Author(s) 2012.

  4. In vitro characterization of cadmium transport along the gastro-intestinal tract of freshwater rainbow trout (Oncorhynchus mykiss)

    International Nuclear Information System (INIS)

    Klinck, Joel S.; Wood, Chris M.

    2011-01-01

    An in vitro gut sac technique was used to examine the mechanism(s) of cadmium (Cd) uptake along the gastro-intestinal tract (GIT) of rainbow trout (Oncorhynchus mykiss). The spatial distribution of Cd between three compartments (mucus-binding, mucosal epithelium, and transport into blood space) was determined using a modified Cortland saline containing 50 μM Cd (as CdCl 2 ) labeled with 109 Cd radiotracer. Taking into account total surface areas, the order of relative importance for total Cd uptake rate was: posterior intestine > anterior intestine > stomach > mid intestine. Cd transport was not inhibited by experimentally reducing fluid transport rates by manipulation of osmotic gradients using mannitol, but was sensitive to internal luminal pressure changes, suggesting a mechanosensitive pathway. Q 10 values (1, 11, and 19 o C) indicated a facilitated transport of Cd in the anterior- and mid-intestine. The effects of 10 mM Ca on the kinetics of Cd uptake suggest the presence of a common uptake pathway for Cd and Ca in the stomach, anterior-, and mid-intestine. Further evidence of a shared route of entry was found using three Ca channel blockers, lanthanum, verapamil, and nifedipine: both voltage-insensitive and voltage-sensitive Ca channels appear to be present in either some, or all portions of the GIT. Elevated Fe (500 μM), Mg (50 mM), and Zn (500 μM) showed varying degrees of inhibition of Cd transport depending on the compartment and segment of the GIT. Overall it appears that there are multiple sites, and mechanisms, of Cd uptake along the GIT of rainbow trout.

  5. Influence of temporal variations in water chemistry on the Pb isotopic composition of rainbow trout (Oncorhynchus mykiss)

    International Nuclear Information System (INIS)

    Miller, Jerry R.; Anderson, Jamie B.; Lechler, Paul J.; Kondrad, Shannon L.; Galbreath, Peter F.; Salter, Emory B.

    2005-01-01

    Field and laboratory investigations were undertaken to determine (1) the relations between discharge, Pb concentration, and the Pb isotopic composition of the dissolved load in Richland Creek, western North Carolina, and (2) the potential influence of varying Pb water chemistry on the Pb isotopic abundances in liver and bone tissues of rainbow trout (Oncorhynchus mykiss). Stream waters were characterized by relatively low Pb concentrations during periods of base flow exceeding 10 days in length. Moreover, greater than 65% of the Pb was derived from orchard soils located upstream of the monitoring site which are contaminated by lead arsenate. During small to moderate floods, the dissolved load exhibited Pb concentrations more than twice as high as those measured during base flow, but the contribution of Pb from lead arsenate was relatively low and varied directly with discharge. In contrast to smaller events, Pb from lead arsenate in an 8- to 10-year (overbank) event in May 2003 was minimal during peak flow conditions, suggesting that discharge-source relations are dependent on flood magnitude. The hydrologic and geochemical data demonstrate that aquatic biota in Richland Creek are subjected to short-term variations in Pb concentrations and Pb isotopic abundances within the dissolved load ranging from a few hours to few a weeks. Laboratory studies demonstrated that when rainbow trout were exposed to elevated Pb concentrations with a distinct isotopic fingerprint, the bone and liver rapidly acquire isotopic ratios similar to that of the water. Following exposure, bone retains Pb from the contaminant source for a period of months, while the liver excreted approximately 50% of the accumulated Pb within a few days and nearly all of the Pb within a few weeks. Differences in the rates of excretion resulted in contrasting isotopic ratios between the tissues. It seems plausible, then, that previously observed differences between the isotopic composition of bone and liver in

  6. The effects of trace metal exposure on agonistic encounters in juvenile rainbow trout, Oncorhynchus mykiss

    International Nuclear Information System (INIS)

    Sloman, K.A.; Baker, D.W.; Ho, C.G.; McDonald, D.G.; Wood, C.M.

    2003-01-01

    The effects of five trace metals, copper, cadmium, nickel, zinc and lead (presented as soluble salts) on the ability of juvenile rainbow trout to form social relationships were investigated. Comparable concentrations of the five metals in relation to their acute 96 h LC50s (concentration at which population mortality=50% at 96 h) were used (i.e. 15% of the 96 h LC50) and water quality parameters (hardness=120 mg l -1 as CaCO 3 , pH 8; DOC=3 mg l -1 ) were kept constant throughout. In the first experiment, trout exposed to sublethal concentrations of cadmium for 24 h displayed significantly lower numbers of aggressive attacks during pair-wise agonistic encounters than fish paired in the copper, nickel, zinc, lead and control water. In a second experiment, fish were exposed to the same concentration of metal for 24 h, and then returned to normal water for 24 h. When these metal pre-exposed fish were paired with non-exposed fish only cadmium pre-exposure had a significant effect on social interaction. All of the cadmium pre-exposed fish became subordinate when paired with non-exposed fish, whereas the probability of a fish pre-exposed to copper, nickel, zinc or lead becoming subordinate did not significantly differ from random. Therefore, at around 15% of the 96 h LC50, different metals exert different effects on the social behaviour of fish, suggesting potential implications for social structure and population stability

  7. Molecular cloning and functional characterization of two forms of Pax8 in the rainbow trout, Oncorhynchus mykiss

    Science.gov (United States)

    Katagiri, Nobuto; Uemae, Youji; Sakamoto, Joe; Hidaka, Yoshie; Susa, Takao; Kato, Yukio; Kimura, Shioko; Suzuki, Masakazu

    2014-01-01

    We have identified two distinct Pax8 (a and b) mRNAs from the thyroid gland of the rainbow trout (Oncorhynchus mykiss), which seemed to be generated by alternative splicing. Both Pax8a and Pax8b proteins were predicted to possess the paired domain, octapeptide, and partial homeodomain, while Pax8b lacked the carboxy-terminal portion due to an insertion in the coding region of the mRNA. RT-PCR analysis showed each of Pax8a and Pax8b mRNAs to be abundantly expressed in the thyroid and kidney. In situ hybridization histochemistry further detected the expression of Pax8 mRNA in the epithelial cells of the thyroid follicles of the adult trout and in the thyroid primordial cells of the embryo. The functional properties of Pax8a and Pax8b were investigated by dual luciferase assay. The transcriptional regulation by the rat thyroid peroxidase (TPO) promoter was found to be increased by Pax8a, but not by Pax8b. Pax8a further showed synergistic transcriptional activity with rat Nkx2-1 for the human TPO upstream region including the enhancer and promoter. On the other hand, Pax8b decreased the synergistic activity of Pax8a and Nkx2-1. Electrophoretic mobility shift assay additionally indicated that not only Pax8a but also Pax8b can bind to the TPO promoter and enhancer, implying that the inhibitory effect of Pax8b might result from the lack of the functional carboxy-terminal portion. Collectively, the results suggest that for the trout thyroid gland, Pax8a may directly increase TPO gene expression in cooperation with Nkx2-1 while Pax8b may work as a non-activating competitor for the TPO transcription. PMID:24380675

  8. The effects of strain and ploidy on the physiological responses of rainbow trout (Oncorhynchus mykiss) to pH 9.5 exposure.

    Science.gov (United States)

    Thompson, William A; Rodela, Tamara M; Richards, Jeffrey G

    2015-05-01

    We characterized the physiological effects of exposure to pH9.5 on one domesticated and four wild strains of diploid and triploid juvenile rainbow trout (Oncorhynchus mykiss) over two consecutive years. In the first year, 35-70% of the individuals from the wild strains showed a loss of equilibrium (LOE) at 12 h exposure to pH9.5, with all fish from wild strains experiencing a LOE by 48 h. In contrast, trout strains and ploidies. Plasma chloride decreased at 24h exposure in all trout strains and ploidies, but recovered by 72 h. No change was observed in plasma sodium. Overall, our data suggest that the domesticated strain of trout is more tolerant of pH9.5 than the wild strains, but these differences in tolerance cannot be explained by our sub-lethal assessment of ammonia balance or ion regulation. Copyright © 2015 Elsevier Inc. All rights reserved.

  9. Four CISH paralogues are present in rainbow trout Oncorhynchus mykiss: differential expression and modulation during immune responses and development.

    Science.gov (United States)

    Maehr, Tanja; Vecino, Jose L González; Wadsworth, Simon; Wang, Tiehui; Secombes, Christopher J

    2014-11-01

    Suppressor of cytokine signalling (SOCS) family members are crucial in the control and attenuation of cytokine induced responses via activation of the JAK/STAT, TLR and NF-kB signalling pathways. SOCS proteins orchestrate the termination of many types of immune responses and are often the targets of microbial pathogens exploiting SOCS mechanisms to evade the host's immune response. Through whole and lineage specific genome duplication events, the teleost cytokine/SOCS network is complex. Not only are the orthologues of all mammalian SOCS members present, namely cytokine inducible Src homology 2 (SH2)-containing protein (CISH) and SOCS-1 to -7, but multiple gene copies exist that may potentially become functionally divergent. In this paper we focus on the CISH genes in rainbow trout (Oncorhynchus mykiss), and have cloned two further paralogues, CISHa2 and CISHb2, additional to the known CISHa1 and CISHb1 genes. We present for the first time a comparative expression analysis of these four paralogues, to establish whether subfunctionalisation is apparent. In vivo examination of gene expression revealed a higher constitutive expression level of CISHa paralogues compared to CISHb expression in adult trout tissues. All CISHs were relatively highly abundant in immune tissues but CISHa2 and CISHb2 had highest expression in the heart and muscle. An inverse picture of CISH abundance during trout ontogeny was seen, and further hints at differential roles of the four genes in immune regulation and development. Stimulation of head kidney (HK) leukocytes with trout recombinant interleukin (rIL)-15 and rIL-21 had a major effect on CISHa2 and to a lesser extent CISHa1 expression. In HK macrophages rIL-1β, phytohemagglutinin, and phorbol 12-myristate 13-acetate also had a strong impact on CISHa2 expression. Yersinia ruckeri infection caused a temporally and spatially differential onset of CISH expression that may be viewed in the context of pathogen evasion strategies. These data

  10. Interactions of copper and thermal stress on mitochondrial bioenergetics in rainbow trout, Oncorhynchus mykiss

    International Nuclear Information System (INIS)

    Sappal, Ravinder; MacDonald, Nicole; Fast, Mark; Stevens, Don; Kibenge, Fred; Siah, Ahmed; Kamunde, Collins

    2014-01-01

    Highlights: • Interacting effects of Cu and temperature were investigated in rainbow trout liver mitochondria. • Mitochondrial functional indices are highly sensitive to temperature change. • High and low temperatures sensitize mitochondria to adverse effects of Cu. • Cu induces a highly temperature-sensitive mitochondrial permeability transition pore. • Cu-imposed mitochondrial membrane potential dissipation is mediated by reactive oxygen species. - Abstract: Thermal stress may influence how organisms respond to concurrent or subsequent chemical, physical and biotic stressors. To unveil the potential mechanisms via which thermal stress modulates metals-induced bioenergetic disturbances, the interacting effects of temperature and copper (Cu) were investigated in vitro. Mitochondria isolated from rainbow trout livers were exposed to a range of Cu concentrations at three temperatures (5, 15 and 25 °C) with measurement of mitochondrial complex I (mtCI)-driven respiratory flux indices and uncoupler-stimulated respiration. Additional studies assessed effects of temperature and Cu on mtCI enzyme activity, induction of mitochondrial permeability transition pore (MPTP), swelling kinetics and mitochondrial membrane potential (MMP). Maximal and basal respiration rates, as well as the proton leak, increased with temperature with the Q 10 effects being higher at lower temperatures. The effect of Cu depended on the mitochondrial functional state in that the maximal respiration was monotonically inhibited by Cu exposure while low and high Cu concentrations stimulated and inhibited the basal respiration/proton leak, respectively. Importantly, temperature exacerbated the effects of Cu by lowering the concentration of the metal required for toxicity and causing loss of thermal dependence of mitochondrial respiration. Mitochondrial complex I activity was inhibited by Cu but was not affected by incubation temperature. Compared with the calcium (Ca) positive control, Cu

  11. Interactions of copper and thermal stress on mitochondrial bioenergetics in rainbow trout, Oncorhynchus mykiss

    Energy Technology Data Exchange (ETDEWEB)

    Sappal, Ravinder [Department of Pathology and Microbiology, Atlantic Veterinary College, University of Prince Edward Island, Charlottetown, PE C1A 4P3 (Canada); Department of Biomedical Sciences, Atlantic Veterinary College, University of Prince Edward Island, Charlottetown, PE C1A 4P3 (Canada); MacDonald, Nicole [Department of Biomedical Sciences, Atlantic Veterinary College, University of Prince Edward Island, Charlottetown, PE C1A 4P3 (Canada); Fast, Mark [Department of Pathology and Microbiology, Atlantic Veterinary College, University of Prince Edward Island, Charlottetown, PE C1A 4P3 (Canada); Stevens, Don [Department of Biomedical Sciences, Atlantic Veterinary College, University of Prince Edward Island, Charlottetown, PE C1A 4P3 (Canada); Kibenge, Fred [Department of Pathology and Microbiology, Atlantic Veterinary College, University of Prince Edward Island, Charlottetown, PE C1A 4P3 (Canada); Siah, Ahmed [British Columbia Centre for Aquatic Health Sciences, 871A Island Highway, Campbell River, BC V9W 2C2 (Canada); Kamunde, Collins, E-mail: ckamunde@upei.ca [Department of Biomedical Sciences, Atlantic Veterinary College, University of Prince Edward Island, Charlottetown, PE C1A 4P3 (Canada)

    2014-12-15

    Highlights: • Interacting effects of Cu and temperature were investigated in rainbow trout liver mitochondria. • Mitochondrial functional indices are highly sensitive to temperature change. • High and low temperatures sensitize mitochondria to adverse effects of Cu. • Cu induces a highly temperature-sensitive mitochondrial permeability transition pore. • Cu-imposed mitochondrial membrane potential dissipation is mediated by reactive oxygen species. - Abstract: Thermal stress may influence how organisms respond to concurrent or subsequent chemical, physical and biotic stressors. To unveil the potential mechanisms via which thermal stress modulates metals-induced bioenergetic disturbances, the interacting effects of temperature and copper (Cu) were investigated in vitro. Mitochondria isolated from rainbow trout livers were exposed to a range of Cu concentrations at three temperatures (5, 15 and 25 °C) with measurement of mitochondrial complex I (mtCI)-driven respiratory flux indices and uncoupler-stimulated respiration. Additional studies assessed effects of temperature and Cu on mtCI enzyme activity, induction of mitochondrial permeability transition pore (MPTP), swelling kinetics and mitochondrial membrane potential (MMP). Maximal and basal respiration rates, as well as the proton leak, increased with temperature with the Q{sub 10} effects being higher at lower temperatures. The effect of Cu depended on the mitochondrial functional state in that the maximal respiration was monotonically inhibited by Cu exposure while low and high Cu concentrations stimulated and inhibited the basal respiration/proton leak, respectively. Importantly, temperature exacerbated the effects of Cu by lowering the concentration of the metal required for toxicity and causing loss of thermal dependence of mitochondrial respiration. Mitochondrial complex I activity was inhibited by Cu but was not affected by incubation temperature. Compared with the calcium (Ca) positive control

  12. ABC transporters and xenobiotic defense systems in early life stages of rainbow trout (Oncorhynchus mykiss).

    Science.gov (United States)

    Kropf, Christian; Segner, Helmut; Fent, Karl

    2016-01-01

    Embryos of oviparous fish, in contrast to (ovo) viviparous species, develop in the aquatic environment, and therefore need solute transport systems at their body surfaces for maintaining internal homeostasis and defending against potentially harmful substances. We hypothesized that solute transporters undergo changes in tissue distribution from the embryo to the larval stage. We therefore studied the mRNA profiles of eight ABC transporters (abcb1a, abcb1b, abcc1, abcc2, abcc3, abcc4, abcc5, abcg2) and three solute carriers (oatp1d, putative oatp2 putative, mate1) in different body regions (head, yolk sac epithelium, abdominal viscera, skin/muscles) of developing rainbow trout. Additionally, we investigated mRNA levels of phase I (cyp1a, cyp3a) and phase II (gstp, putative ugt1, putative ugt2) biotransformation enzymes. The study covered the developmental period from the eleuthero-embryo stage to the first-feeding larval stage (1-20days post-hatch, dph). At 1dph, transcripts of abcc2, abcc4, abcg2, cyp3a, gstp, putative mate1, and putative oatp2 occurred primarily in the yolk sac epithelium, whereas at later stages expression of these genes was predominantly observed in the abdominal viscera. The functional activity of ABC transporters in fish early life stages was assessed by rhodamine B accumulation assays. Finally, we investigated the potential impact of xenobiotics (clotrimazole, clofibric acid) on the ABC and biotransformation systems of trout early life stages. While clofibric acid had no effect, clotrimazole lead to an increased rhodamine B accumulation. The results provide evidence that the transition from the eleuthero-embryo to the larval stage is accompanied by a major alteration in tissue expression of ABC transporters. Copyright © 2016 Elsevier Inc. All rights reserved.

  13. Some Diagnosis and Therapy Techniques in Rainbow Trout (Oncorhynchus Mykiss Furunculosis, in Intensive System Bred

    Directory of Open Access Journals (Sweden)

    Octavian Negrea

    2010-10-01

    Full Text Available Clinical and paraclinical investigations (morpho-pathologic, bacterioscopic, bacteriologic and sensitiveness test toantibodies done on 20 fish (rainbow trout, dead or in agony state, taken from a furunculosis pesthole in Salmonidaeand proceeded from an intensive exploitation unit of trout, in Cluj county, put in evidence the following aspects :Toclinical exam, in breeding basins, it appears individuals (5 % which have presented locomotor troubles, listless anduntidy swimming in water surface, lateral swimming anorexia, and on tegument it is observed diffuse hemorrhagiczones, lost of fish scale and necrosis of fins. It appears also secondary infections with fungi of Saprolegnia genusunder the form of a white- dirty, downy film. From the 20 trut corpses were isolated 2 bacterial strains, from anteriorkidney and from raclage in fin basis, with congestive lesions. Bacteria isolated are developing only after anincubation at 20 – 250 C and does not grow up to 370 C, and to microscopic exam directly from sauce, the mobility isabsent Classic biochemical tests put in evidence the following positive biochemic properties: cataloze, oxidaze,indolal and the presence of hemolytic activity. Biochemical properties testing on API20E gallery also puts inevidence properties as : positive gelatinousis and sucraze fermentation. Based on bacterial strains developmentisolated only to 20 - 250C and the above mentioned biochemic properties, respectively the absence of pigment,bacterial strains isolated are appointed in Aeromonas genus, Aeromonas salmonicida species, achromogenessubspecies. By sensitiveness test in different medicine substances, using antibiogram technique, bacterial strainsisolated from pesthole are sensitive in a decreasing order to: nalidixic acid, oxitetracycline, florfenicol andeurofloxacin and resistant to ampicyline, amoxiclav and colistin.

  14. Characterization of dietary Ni uptake in the rainbow trout, Oncorhynchus mykiss.

    Science.gov (United States)

    Leonard, Erin M; Nadella, Sunita R; Bucking, Carol; Wood, Chris M

    2009-07-26

    We characterized dietary Ni uptake in the gastrointestinal tract of rainbow trout using both in vivo and in vitro techniques. Adult trout were fed a meal (3% of body mass) of uncontaminated commercial trout chow, labeled with an inert marker (ballotini beads). In vivo dietary Ni concentrations in the supernatant (fluid phase) of the gut contents averaged from 2 micromoll(-1) to 24 micromoll(-1), and net overall absorption efficiency of dietary Ni was approximately 50% from the single meal, similar to that for the essential metal Cu, adding to the growing evidence of Ni essentiality. The stomach and mid-intestine emerged as important sites of Ni uptake in vivo, accounting for 78.5% and 18.9% of net absorption respectively, while the anterior intestine was a site of net secretion. Most of the stomach uptake occurred in the first 4h. In vitro gut sac studies using radiolabeled Ni (at 30 micromoll(-1)) demonstrated that unidirectional uptake occurred in all segments, with area-weighted rates being highest in the anterior intestine. Differences between in vivo and in vitro results likely reflect the favourable uptake conditions in the stomach, and biliary secretion of Ni in the anterior intestine in vivo. The concentration-dependent kinetics of unidirectional Ni uptake in vitro were biphasic in nature, with a saturable Michaelis-Menten relationship observed at 1-30 micromoll(-1) Ni (K(m) - 11 micromoll(-1), J(max) - 53 pmolcm(-2)h(-1) in the stomach and K(m) - 42 micromoll(-1), J(max) - 215 pmolcm(-2)h(-1) in the mid-intestine), suggesting mediation by a channel or carrier process. A linear uptake relationship was seen at higher concentrations, indicative of simple diffusion. Ni uptake (at 30 micromoll(-1)) into the blood compartment was significantly reduced in the stomach by high Mg (50 mmoll(-1)), and in the mid-intestine by both Mg (50 mmoll(-1)) and Ca (50 mmoll(-1)). In both regions, kinetic analysis demonstrated reductions in J(max) with unchanged K

  15. Pros and cons of fish skin cells in culture: long-term full skin and short-term scale cell culture from rainbow trout, Oncorhynchus mykiss.

    Science.gov (United States)

    Rakers, Sebastian; Klinger, Matthias; Kruse, Charli; Gebert, Marina

    2011-12-01

    Here, we report the establishment of a permanent skin cell culture from rainbow trout (Oncorhynchus mykiss). The cells of the fish skin cell culture could be propagated over 60 passages so far. Furthermore, we show for the first time that it is possible to integrate freshly harvested rainbow trout scales into this new fish skin cell culture. We further demonstrated that epithelial cells derived from the scales survived in the artificial micro-environment of surrounding fibroblast-like cells. Also, antibody staining indicated that both cell types proliferated and started to build connections with the other cell type. It seems that it is possible to generate an 'artificial skin' with two different cell types. This could lead to the development of a three-dimensional test system, which might be a better in vitro representative of fish skin in vivo than individual skin cell lines. Copyright © 2011 Elsevier GmbH. All rights reserved.

  16. Transcriptome Analyses Reveal Lipid Metabolic Process in Liver Related to the Difference of Carcass Fat Content in Rainbow Trout (Oncorhynchus mykiss

    Directory of Open Access Journals (Sweden)

    Guo Hu

    2016-01-01

    Full Text Available Excessive accumulation of carcass fat in farm animals, including fish, has a significant impact on meat quality and on the cost of feeding. Similar to farmed animals and humans, the liver can be considered one of the most important organs involved in lipid metabolism in rainbow trout (Oncorhynchus mykiss. RNA-seq based whole transcriptome sequencing was performed to liver tissue of rainbow trout with high and low carcass fat content in this study. In total 1,694 differentially expressed transcripts were identified, including many genes involved in lipid metabolism, such as L-FABP, adiponectin, PPAR-α, PPAR-β, and IGFBP1a. Evidence presented in this study indicated that lipid metabolic process in liver may be related to the difference of carcass fat content. The relevance of PPAR-α and PPAR-β as molecular markers for fat storage in liver should be worthy of further investigation.

  17. Positive correlation between Aeromonas salmonicida vaccine antigen concentration and protection in vaccinated rainbow trout Oncorhynchus mykiss evaluated by a tail fin infection model

    DEFF Research Database (Denmark)

    Marana, M. H.; Skov, J.; Chettri, Jiwan Kumar

    2017-01-01

    Rainbow trout, Oncorhynchus mykiss (Walbaum), are able to raise a protective immune response against Aeromonas salmonicida subsp. salmonicida (AS) following injection vaccination with commercial vaccines containing formalin-killed bacteria, but the protection is often suboptimal under Danish...... mariculture conditions. We elucidated whether protection can be improved by increasing the concentration of antigen (formalin-killed bacteria) in the vaccine. Rainbow trout juveniles were vaccinated by intraperitoneal (i.p.) injection with a bacterin of Aeromonas salmonicida subsp. salmonicida strain 090710...... bacteria. The infection method proved to be efficient and could differentiate efficacies of different vaccines. It was shown that protection and antibody production in exposed fish were positively correlated to the AS antigen concentration in the vaccine....

  18. Determination of the exposure parameters that maximise the concentrations of the anaesthetic/sedative eugenol in rainbow trout (Oncorhynchus mykiss) skin-on fillet tissue

    Science.gov (United States)

    Meinertz, Jeffery R.; Porcher, Scott T.; Smerud, Justin R.

    2014-01-01

    Studies were conducted to determine the anaesthetic/sedative concentrations and durations that would maximize anaesthetic/sedative residue concentrations in rainbow trout (Oncorhynchus mykiss) skin-on fillet tissue. Rainbow trout (167–404 g) were exposed to 50 mg l−1 AQUI-S® 20E (10% active ingredient, eugenol) in 17°C freshwater for durations up to 1440 min, 100 and 250 mg l−1 AQUI-S® 20E for durations up to 240 min, and 500 and 1000 mg l−1 AQUI-S® 20E for durations up to 90 min. Fish exposed to 100 mg l−1 AQUI-S® 20E for durations of 30, 60, 120 and 240 min had the greatest eugenol concentrations in the fillet tissue, 50, 58, 54 and 62 µg g−1, respectively. All other exposure concentrations and durations resulted in significantly lower eugenol concentrations, i.e. all −1.

  19. Determination of the exposure parameters that maximise the concentrations of the anaesthetic/sedative eugenol in rainbow trout (Oncorhynchus mykiss) skin-on fillet tissue.

    Science.gov (United States)

    Meinertz, J R; Porcher, S T; Smerud, J R; Gaikowski, M P

    2014-01-01

    Studies were conducted to determine the anaesthetic/sedative concentrations and durations that would maximise anaesthetic/sedative residue concentrations in rainbow trout (Oncorhynchus mykiss) skin-on fillet tissue. Rainbow trout (167-404 g) were exposed to 50 mg l(-1) AQUI-S(®) 20E (10% active ingredient, eugenol) in 17°C freshwater for durations up to 1440 min, 100 and 250 mg l(-1) AQUI-S(®) 20E for durations up to 240 min, and 500 and 1000 mg l(-1) AQUI-S(®) 20E for durations up to 90 min. Fish exposed to 100 mg l(-1) AQUI-S(®) 20E for durations of 30, 60, 120 and 240 min had the greatest eugenol concentrations in the fillet tissue, 50, 58, 54 and 62 µg g(-1), respectively. All other exposure concentrations and durations resulted in significantly lower eugenol concentrations, i.e. all < 39 µg g(-1).

  20. Processing yield and chemical composition of rainbow trout (Oncorhynchus mykiss with regard to body weight

    Directory of Open Access Journals (Sweden)

    Maria Luiza Rodrigues de Souza

    2015-05-01

    Full Text Available The influence of weight (W category of the rainbow trout on processing yield and chemical composition of the entire eviscerated fish and fish fillet was analyzed. A completely randomized design was employed for processing variables (W1 = 300 to 370 g and W2 = 371 to 440 coupled to a 2 x 2 factorial scheme for the chemical composition (W1 and W2 and forms of presentation: fillet and whole eviscerated fish. W1 showed higher yield for entire eviscerated fish (83.00% and head (13.27%, but a lower yield for the viscera (17.00%, when compared to W2. We did not affect abdominal muscle yield, fillet with or without skin, skin percentage and residues. There were significant differences between W for moisture (W1 = 72.30% and W2 = 71.15% and lipids (CP1 = 7.96% and CP2 = 9.04% rates. Fillet moisture contents (73.74% and crude protein (19.05% were higher (p < 0.01 than for entire eviscerated fish (69.71% and 17.81%, respectively. Ash (2.15% and lipid (10.48% rates were higher (p < 0.01 for entire fish when compared to those of fillets (1.16% and 6.52%, respectively. The slaughter of fish weighing between 300 and 370 g and their fillets are more adequate for the market.

  1. Probiotic bacteria Lactobacillus rhamnosus influences the blood profile in rainbow trout Oncorhynchus mykiss (Walbaum).

    Science.gov (United States)

    Panigrahi, A; Kiron, V; Satoh, S; Watanabe, T

    2010-12-01

    This paper reports the effect of feeding probiotic diets on blood profiles in rainbow trout. Two experiments were performed: in the first, fish of average weight 75 g were offered either a commercial feed or the same incorporated with 10(9) CFU g(-1) of lactic acid bacteria Lactobacillus rhamnosus for 30 days; in the second study performed for a similar duration, fish of average weight 126 g were offered formulated diets that either contained the same bacteria in heat-killed or freeze-dried form (nearly 10(11) CFU g(-1)), or the basal diet without the bacteria. Blood samples were collected at different times after commencement of probiotic feeding to determine the total cholesterol, triglyceride contents, the plasma alkaline phosphatase activity, plasma protein and hematocrit value. The plasma cholesterol significantly increased upon probiotic feeding in the first experiment. A significant elevation (Pfeeding. Thus, alterations in the blood profiles could serve as supplementary information when examining the benefits of probiotics for fish.

  2. Exotic "Gill Lice" Species (Copepoda: Lernaeopodidae: Salmincola SPP.) Infect Rainbow Trout (Oncorhynchus mykiss) and Brook Trout (Salvelinus fontinalis) in the Southeastern United States.

    Science.gov (United States)

    Ruiz, Carlos F; Rash, Jacob M; Besler, Doug A; Roberts, Jackson R; Warren, Micah B; Arias, Cova R; Bullard, Stephen A

    2017-08-01

    Salmincola californiensis infected 25 of 31 (prevalence 0.8; intensity 2-35 [mean 6.6 ± standard deviation 7.7; n = 25]) rainbow trout, Oncorhynchus mykiss, from a private trout farm connected to the Watauga River, North Carolina. Salmincola edwardsii infected all of 9 (1.0; 2-43 [9.3 ± 13.0; 9]) brook trout, Salvelinus fontinalis, from Big Norton Prong, a tributary of the Little Tennessee River, North Carolina. Both lernaeopodids are well-known salmonid pathogens, but neither is native to, nor has been previously taxonomically confirmed from, the southeastern United States. Herein, we (1) use light and scanning electron microscopy to identify and provide supplemental morphological observations of these lernaeopodids, (2) furnish complementary molecular sequence data from the 28S rDNA (28S), and (3) document the pathological effects of gill infections. We identified and differentiated these lernaeopodids by the second antenna (exopod tip with large [S. californiensis] vs. slender [S. edwardsii] spines; endopod terminal segment with subequal ventral processes shorter than [S. californiensis] vs. longer than or equal to [S. edwardsii] dorsal hook), maxilliped palp (length typically ≤1/3 [S. californiensis] vs. 1/3-1/2 [S. edwardsii] subchela length exclusive of claw), and bulla (sub-circular and concave on manubrium's side [S. californiensis] vs. non-stellate [S. edwardsii]). Analysis of the 28S rDNA sequences confirmed our taxonomic assignments as demonstrated by 100% sequence similarity among the sympatric, morphologically-conspecific isolates. Histopathology revealed focal gill epithelial hyperplasia, obstruction of interlamellar water channels, lamellar fusion, and crypting of gill filaments. High intensity infections by either lernaeopodid are surveillance-worthy because they are potentially pathogenic to trout in the southeastern United States.

  3. Physiological and molecular ontogeny of branchial and extra-branchial urea excretion in posthatch rainbow trout (Oncorhynchus mykiss).

    Science.gov (United States)

    Zimmer, Alex M; Wood, Chris M

    2016-02-01

    All teleost fish produce ammonia as a metabolic waste product. In embryos, ammonia excretion is limited by the chorion, and fish must detoxify ammonia by synthesizing urea via the ornithine urea cycle (OUC). Although urea is produced by embryos and larvae, urea excretion (J(urea)) is typically low until yolk sac absorption, increasing thereafter. The aim of this study was to determine the physiological and molecular characteristics of J(urea) by posthatch rainbow trout (Oncorhynchus mykiss). Following hatch, whole body urea concentration decreased over time, while J(urea) increased following yolk sac absorption. From 12 to 40 days posthatch (dph), extra-branchial routes of excretion accounted for the majority of J(urea), while the gills became the dominant site for J(urea) only after 55 dph. This represents the most delayed branchial ontogeny of any process studied to date. Urea transporter (UT) gene expression in the gills and skin increased over development, consistent with increases in branchial and extra-branchial J(urea). Following exposure to 25 mmol/l urea, the accumulation and subsequent elimination of exogenous urea was much greater at 55 dph than 12 dph, consistent with increased UT expression. Notably, UT gene expression in the gills of 55 dph larvae increased in response to high urea. In summary, there is a clear increase in urea transport capacity over posthatch development, despite a decrease in OUC activity. Copyright © 2016 the American Physiological Society.

  4. Swimming performance, venous oxygen tension and cardiac performance of coronary-ligated rainbow trout, Oncorhynchus mykiss, exposed to progressive hypoxia

    DEFF Research Database (Denmark)

    Steffensen, J F; Farrell, A P

    1998-01-01

    We performed in vivo studies to examine the idea that cardiac work is impaired in rainbow trout (Oncorhynchus mykiss) below a certain venous PO2 threshold. We hypothesized that coronary-ligated fish, swimming continuously at a reasonably high water velocity (1.5 body lengths x s(-1)) and exposed...... to progressive hypoxia, would fatigue at higher venous PO2 and ambient water PO2 compared with sham-operated fish. However, we found that both the lowest venous PO2 that supported hypoxic swimming (9.9 torr for coronary-ligated fish and 11.1 torr for sham-operated fish) and the venous PO2 at fatigue (7.8 torr...... and 8.6 torr, respectively) were the same for coronary-ligated and sham-operated fish. Also, both groups quit swimming at the same water PO2 heart rate and hematocrit. Nevertheless, significant differences in cardiac performance did exist between the two groups. Whereas ventral aortic blood pressure...

  5. The partial pressure of oxygen affects biomarkers of oxidative stress in cultured rainbow trout (Oncorhynchus mykiss) hepatocytes.

    Science.gov (United States)

    Finne, E F; Olsvik, P A; Berntssen, M H G; Hylland, K; Tollefsen, K E

    2008-09-01

    Oxidative stress, the imbalance between production of reactive oxygen species and the cellular detoxification of these reactive compounds, is believed to be involved in the pathology of various diseases. Several biomarkers for oxidative stress have been proposed to serve as tools in toxicological and ecotoxicological research. Not only may exposure to various pro-oxidants create conditions of cellular oxidative stress, but hyperoxic conditions may also increase the production of reactive oxygen species. The objective of the current study was to determine the extent to which differences in oxygen partial pressure would affect biomarkers of oxidative stress in a primary culture of hepatocytes from rainbow trout (Oncorhynchus mykiss). Membrane integrity, metabolic activity, levels of total and oxidized glutathione (tGSH/GSSG) was determined, as well as mRNA expression levels of the antioxidant enzymes superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px), glutathione reductase (GSSG-R), gamma-glutamyl-cystein synthetase (GCS) and thioredoxin (TRX). The results show that different biomarkers of oxidative stress are affected when the cell culture is exposed to atmospheric oxygen, and that changes such as increased GSSG content and induction of GSSG-R and GSH-Px can be reduced by culturing the cells under lower oxygen tension. Oxygen tension may thus influence results of in vitro based cell research and is particularly important when assessing parameters in the antioxidant defence system. Further research is needed to establish the magnitude of this effect in different cellular systems.

  6. Influence of the seaweed Ascophyllum nodosum as a growth promoter in the stage of rainbow trout (Oncorhynchus mykiss

    Directory of Open Access Journals (Sweden)

    Diego López

    2017-12-01

    Full Text Available The quality of the algae Ascphyllum nodosum was assessed as a growth promoter in the breeding stage of Rainbow Trout (Oncorhynchus mykiss and its immunostimulant effect with regard to fungal diseases as the Saprolegnia sp. 6000 fingerlings of 77 days of age were used, with an average weight of 0.15 g, distributed under a DCA. For the analysis of the results, it was applied the analysis of variance and separation of averages (Duncan to p<0.05, orthogonal comparisons and chi square. The seaweed Ascophyllum nodosum added as nutritional supplement in the growth stage with a level of 2% and 98% of concentrated food was the one that reached the best zoo technical and economic results: initial weight 0.84 g, daily weight gain 0.30 g, final weight 34.60 g., nutritive conversion 0.19, mortality 4.60%, and the cost of production per kilo of meat is $35.24. Regarding the mycotic challenge (fungus Saprolegnia sp., the administration of the seaweed Ascophyllum nodosum on the percentages of 2%, 2.5% and 3% as nutritional supplement, provided resistance to the fingerlings.

  7. Elemental signatures in otoliths of hatchery rainbow trout (Oncorhynchus mykiss): Distinctiveness and utility fo detecting origins and movement

    Science.gov (United States)

    Gibson-Reinemer, D. K.; Johnson, B.M.; Martinez, P.J.; Winkelman, D.L.; Koenig, A.E.; Woodhead, J.D.

    2009-01-01

    Otolith chemistry in freshwater has considerable potential to reveal patterns of origin and movement, which would benefit traditional fisheries management and provide a valuable tool to curb the spread of invasive and illicitly stocked species. We evaluated the relationship between otolith and water chemistry for five markers (Ba/Ca, Mn/Ca, Sr/ Ca, Zn/Ca, and 87Sr/86Sr) in rainbow trout (Oncorhynchus mykiss) using the existing hatchery system in Colorado and Wyoming, USA, to provide controlled, seminatural conditions. Otolith Ba/Ca, Sr/Ca, and 87Sr/86Sr reflected ambient levels, whereas Mn/Ca and Zn/Ca did not. Using only the markers correlated with water chemistry, we classified fish to their hatchery of origin with up to 96% accuracy when element and isotope data were used together. Large changes in 87Sr/Sr were evident in otolith transects, although subtler changes in Sr/Ca were also detectable. Our results suggest the relatively few otolith markers that reflect ambient chemistry can discriminate among locations and track movements well enough to provide valuable insight in a variety of applied contexts.

  8. Enhancement of the immune response and protection induced by probiotic lactic acid bacteria against furunculosis in rainbow trout (Oncorhynchus mykiss).

    Science.gov (United States)

    Balcázar, José Luis; de Blas, Ignacio; Ruiz-Zarzuela, Imanol; Vendrell, Daniel; Gironés, Olivia; Muzquiz, José Luis

    2007-10-01

    We analysed the effect of probiotic strains on the cellular and humoral immune responses of rainbow trout (Oncorhynchus mykiss), and their capacity to prevent furunculosis during a challenge trial. Probiotic strains (Lactococcus lactis ssp. lactis CLFP 100, Leuconostoc mesenteroides CLFP 196, and Lactobacillus sakei CLFP 202) were administered orally to fish for 2 weeks at 10(6) CFU g(-1) of feed. In comparison to untreated control fish, the phagocytic activity of head kidney leukocytes and the alternative complement activity in serum were significantly greater in all probiotic groups at the end of the second week. With the exception of the group fed with Lactobacillus sakei, superoxide anion production was also significantly increased in the probiotic groups. Analysis of lysozyme activity did not exhibit any significant difference in the probiotic and control groups. Fifteen days after the start of the probiotic feeding, fish were challenged with Aeromonas salmonicida ssp. salmonicida. The fish supplemented with probiotics exhibited survival rates ranging from 97.8% to 100%, whereas survival was 65.6% in fish not treated with the probiotics. These results demonstrate that probiotic supplementation to fish can reduce the severity of furunculosis, and suggest that this reduction may be associated with enhanced humoral and cellular immune response.

  9. Effects of temperature on disease progression and swimming stamina in Ichthyophonus-infected rainbow trout, Oncorhynchus mykiss (Walbaum).

    Science.gov (United States)

    Kocan, R; Hershberger, P; Sanders, G; Winton, J

    2009-10-01

    Rainbow trout, Oncorhynchus mykiss, were infected with Ichthyophonus sp. and held at 10 degrees C, 15 degrees C and 20 degrees C for 28 days to monitor mortality and disease progression. Infected fish demonstrated more rapid onset of disease, higher parasite load, more severe host tissue reaction and reduced mean-day-to-death at higher temperature. In a second experiment, Ichthyophonus-infected fish were reared at 15 degrees C for 16 weeks then subjected to forced swimming at 10 degrees C, 15 degrees C and 20 degrees C. Stamina improved significantly with increased temperature in uninfected fish; however, this was not observed for infected fish. The difference in performance between infected and uninfected fish became significant at 15 degrees C (P = 0.02) and highly significant at 20 degrees C (P = 0.005). These results have implications for changes in the ecology of fish diseases in the face of global warming and demonstrate the effects of higher temperature on the progression and severity of ichthyophoniasis as well as on swimming stamina, a critical fitness trait of salmonids. This study helps explain field observations showing the recent emergence of clinical ichthyophoniasis in Yukon River Chinook salmon later in their spawning migration when water temperatures were high, as well as the apparent failure of a substantial percentage of infected fish to successfully reach their natal spawning areas.

  10. Effects of temperature on disease progression and swimming stamina in Ichthyophonus-infected rainbow trout, Oncorhynchus mykiss (Walbaum)

    Science.gov (United States)

    Kocan, R.; Hershberger, P.; Sanders, G.; Winton, J.

    2009-01-01

    Rainbow trout, Oncorhynchus mykiss, were infected with Ichthyophonus sp. and held at 10 ??C, 15 ??C and 20 ??C for 28 days to monitor mortality and disease progression. Infected fish demonstrated more rapid onset of disease, higher parasite load, more severe host tissue reaction and reduced mean-day-to-death at higher temperature. In a second experiment, Ichthyophonus-infected fish were reared at 15 ??C for 16 weeks then subjected to forced swimming at 10 ??C, 15 ??C and 20 ??C. Stamina improved significantly with increased temperature in uninfected fish; however, this was not observed for infected fish. The difference in performance between infected and uninfected fish became significant at 15 ??C (P = 0.02) and highly significant at 20 ??C (P = 0.005). These results have implications for changes in the ecology of fish diseases in the face of global warming and demonstrate the effects of higher temperature on the progression and severity of ichthyophoniasis as well as on swimming stamina, a critical fitness trait of salmonids. This study helps explain field observations showing the recent emergence of clinical ichthyophoniasis in Yukon River Chinook salmon later in their spawning migration when water temperatures were high, as well as the apparent failure of a substantial percentage of infected fish to successfully reach their natal spawning areas. ?? 2009 Blackwell Publishing Ltd.

  11. Combined effects of diets and temperature on mitochondrial function, growth and nutrient efficiency in rainbow trout (Oncorhynchus mykiss).

    Science.gov (United States)

    Eya, Jonathan C; Yossa, Rodrigue; Perera, Dayan; Okubajo, Olasupo; Gannam, Ann

    2017-10-01

    A 4×3 factorial experiment was conducted to evaluate the effects of two dietary protein sources (mixed fishmeal/plant protein-, and plant protein- based diet), two dietary lipid levels (10% and 20%) and three water temperatures (10°C, 14°C, and 18°C) on the growth performance, nutrient utilization efficiencies and mitochondrial enzyme complex activities in rainbow trout Oncorhynchus mykiss (average weight±SD, 39.5±5g) over a 180day rearing period. At the end of the experiment, weight gain (WG), condition factor (CF), and feed efficiency (FE) were significantly affected by diet×temperature interaction (Ptrout would be to use 40/10PP diet at 14°C because fish fed this treatment had a weight gain comparable to that of the fish fed the more expensive experimental diets (40/10 FM/PP, 40/20 FM/PP, and 40/20 PP). Copyright © 2017 Elsevier Inc. All rights reserved.

  12. Functional Diets Modulate lncRNA-Coding RNAs and Gene Interactions in the Intestine of Rainbow Trout Oncorhynchus mykiss.

    Science.gov (United States)

    Núñez-Acuña, Gustavo; Détrée, Camille; Gallardo-Escárate, Cristian; Gonçalves, Ana Teresa

    2017-06-01

    The advent of functional genomics has sparked the interest in inferring the function of non-coding regions from the transcriptome in non-model species. However, numerous biological processes remain understudied from this perspective, including intestinal immunity in farmed fish. The aim of this study was to infer long non-coding RNA (lncRNAs) expression profiles in rainbow trout (Oncorhynchus mykiss) fed for 30 days with functional diets based on pre- and probiotics. For this, whole transcriptome sequencing was conducted through Illumina technology, and lncRNAs were mined to evaluate transcriptional activity in conjunction with known protein sequences. To detect differentially expressed transcripts, 880 novels and 9067 previously described O. mykiss lncRNAs were used. Expression levels and genome co-localization correlations with coding genes were also analyzed. Significant differences in gene expression were primarily found in the probiotic diet, which had a twofold downregulation of lncRNAs compared to other treatments. Notable differences by diet were also evidenced between the coding genes of distinct metabolic processes. In contrast, genome co-localization of lncRNAs with coding genes was similar for all diets. This study contributes novel knowledge regarding lncRNAs in fish, suggesting key roles in salmons fed with in-feed additives with the capacity to modulate the intestinal homeostasis and host health.

  13. Increased gastrointestinal blood flow: An essential circulatory modification for euryhaline rainbow trout (Oncorhynchus mykiss) migrating to sea

    Science.gov (United States)

    Brijs, Jeroen; Axelsson, Michael; Gräns, Albin; Pichaud, Nicolas; Olsson, Catharina; Sandblom, Erik

    2015-01-01

    The large-scale migrations of anadromous fish species from freshwater to seawater have long been considered particularly enigmatic, as this life history necessitates potentially energetically costly changes in behaviour and physiology. A significant knowledge gap concerns the integral role of cardiovascular responses, which directly link many of the well-documented adaptations (i.e. through oxygen delivery, water and ion transport) allowing fish to maintain osmotic homeostasis in the sea. Using long-term recordings of cardiorespiratory variables and a novel method for examining drinking dynamics, we show that euryhaline rainbow trout (Oncorhynchus mykiss) initiate drinking long before the surrounding environment reaches full seawater salinity (30–33 ppt), suggesting the presence of an external osmo-sensing mechanism. Onset of drinking was followed by a delayed, yet substantial increase in gastrointestinal blood flow through increased pulse volume exclusively, as heart rate remained unchanged. While seawater entry did not affect whole animal energy expenditure, enhanced gastrointestinal perfusion represents a mechanism crucial for ion and water absorption, as well as possibly increasing local gastrointestinal oxygen supply. Collectively, these modifications are essential for anadromous fish to maintain homeostasis at sea, whilst conserving cardiac and metabolic scope for activities directly contributing to fitness and reproductive success. PMID:26000616

  14. Topographical Mapping of the Rainbow Trout (Oncorhynchus mykiss) Microbiome Reveals a Diverse Bacterial Community with Antifungal Properties in the Skin

    Science.gov (United States)

    Lowrey, Liam; Woodhams, Douglas C.; Tacchi, Luca

    2015-01-01

    The mucosal surfaces of wild and farmed aquatic vertebrates face the threat of many aquatic pathogens, including fungi. These surfaces are colonized by diverse symbiotic bacterial communities that may contribute to fight infection. Whereas the gut microbiome of teleosts has been extensively studied using pyrosequencing, this tool has rarely been employed to study the compositions of the bacterial communities present on other teleost mucosal surfaces. Here we provide a topographical map of the mucosal microbiome of an aquatic vertebrate, the rainbow trout (Oncorhynchus mykiss). Using 16S rRNA pyrosequencing, we revealed novel bacterial diversity at each of the five body sites sampled and showed that body site is a strong predictor of community composition. The skin exhibited the highest diversity, followed by the olfactory organ, gills, and gut. Flectobacillus was highly represented within skin and gill communities. Principal coordinate analysis and plots revealed clustering of external sites apart from internal sites. A highly diverse community was present within the epithelium, as demonstrated by confocal microscopy and pyrosequencing. Using in vitro assays, we demonstrated that two Arthrobacter sp. skin isolates, a Psychrobacter sp. strain, and a combined skin aerobic bacterial sample inhibit the growth of Saprolegnia australis and Mucor hiemalis, two important aquatic fungal pathogens. These results underscore the importance of symbiotic bacterial communities of fish and their potential role for the control of aquatic fungal diseases. PMID:26209676

  15. Effects of Using Tricaine Methanesulfonate and Metomidate before Euthanasia on the Contractile Properties of Rainbow Trout (Oncorhynchus mykiss) Myocardium.

    Science.gov (United States)

    Roberts, Jordan C; Syme, Douglas A

    2016-01-01

    Because many anesthetics work through depressing cell excitability, unanesthetized euthanasia has become common for research involving excitable tissues (for example muscle and nerve) to avoid these depressive effects. However, anesthetic use during euthanasia may be indicated for studies involving isolated tissues if the potential depressive effects of brief anesthetic exposure dissipate after subsequent tissue isolation, washout, and saline perfusion. We explore this here by measuring whether, when applied prior to euthanasia, standard immersion doses of 2 fish anesthetics, tricaine methanesulfonate (TMS; 100 mg/L, n = 6) and methyl 1-(1-phenylethyl)-1H-imidazole-5-carboxylate (metomidate, 10 mg/L, n = 6), have residual effects on the contractile properties (force and work output) of isolated and saline-perfused ventricular compact myocardium from rainbow trout (Oncorhynchus mykiss). Results suggest that direct exposure of muscle to immersion doses of TMS-but not metomidate-impairs muscle contractile performance. However, brief exposure (2 to 3 min) to either anesthetic during euthanasia only-providing that the agent is washed out prior to tissue experimentation-does not have an effect on the contractile properties of the myocardium. Therefore, the use of TMS, metomidate, and perhaps other anesthetics that depress cell excitability during euthanasia may be indicated when conducting research on isolated and rinsed tissues.

  16. Oxidative stress and antioxidant defence markers in muscle tissue of rainbow trout (Oncorhynchus mykiss after vaccination against Yersinia ruckeri

    Directory of Open Access Journals (Sweden)

    Tkachenko Halyna

    2016-03-01

    Full Text Available Introduction: The goal of this study was to assess the influence of vaccination against enteric redmouth disease on oxidative stress biomarkers and antioxidant defence in the muscle tissue of rainbow trout (Oncorhynchus mykiss Walbaum vaccinated against Yersinia ruckeri in the first and second month after immunisation. Material and Methods: Healthy fish were vaccinated orally with inactivated whole cells of a virulent strain of Y. ruckeri. One and two months after immunisation the muscle samples were collected. Results: No significant difference was noted in lipid peroxidation level in either the first or second month after vaccination, while aldehydic and ketonic derivatives of oxidatively modified proteins (OMB in the vaccinated group were significantly lower in the second month compared to those in the first month after vaccination (P < 0.05. The content of ketonic derivatives of OMB in muscles in the first month after immunisation was higher compared to untreated control. All these culminated in a depletion of glutathione peroxidase (GPx activity and low level of total antioxidant capacity (TAC. Conclusion: Correlations between catalase activity and lipid peroxidation and TAC confirmed the pivotal role of catalase in antioxidant defence during immunisation. From a broader perspective, it is suggested that immunisation of fish with Yersinia vaccine is associated with induced free radical formation and oxidative stress. Free radicals would therefore be at least partially responsible for the induction of both humoral and cellular elements of the immunity and increased protective immunity against Y. ruckeri infection.

  17. Organically bound tritium (OBT) formation in rainbow trout (Oncorhynchus mykiss): HTO and OBT-spiked food exposure experiments.

    Science.gov (United States)

    Kim, S B; Shultz, C; Stuart, M; McNamara, E; Festarini, A; Bureau, D P

    2013-02-01

    In order to determine the rate of organically bound tritium (OBT) formation, rainbow trout (Oncorhynchus mykiss) were exposed to tritiated water (HTO) or OBT-spiked food. The HTO (in water) exposure study was conducted using a tritium activity concentration of approximately 7000 Bq/L and the OBT (in food) exposure study was conducted using a tritium activity concentration of approximately 30,000 Bq/L. Fish in both studies were expected to be exposed to similar tritium levels assuming 25% incorporation of the tritiated amino acids found in the food. Four different sampling campaigns of HTO exposure (Day 10, 30, 70, 140) and five different sampling campaigns of OBT-spiked food exposure (Day 9, 30, 70, 100, 140) were conducted to measure HTO and OBT activity concentrations in fish tissues. OBT depuration was also evaluated over a period of 30 days following the 140 d exposure studies. The results suggested that the OBT formation rate was slower when the fish were exposed to HTO compared to when the fish were ingesting OBT. In addition, the results indicated that OBT can bioaccumulate in fish tissues following OBT-spiked food exposure. Crown Copyright © 2012. Published by Elsevier Ltd. All rights reserved.

  18. Immunological responses and disease resistance of rainbow trout (Oncorhynchus mykiss) juveniles following dietary administration of stinging nettle (Urtica dioica).

    Science.gov (United States)

    Saeidi Asl, Mohammad Reza; Adel, Milad; Caipang, Christopher Marlowe A; Dawood, Mahmoud A O

    2017-12-01

    The present study investigated the effects of dietary supplementation of stinging nettle (Urtica dioica) on growth performance, skin mucus, immune response and disease resistance of rainbow trout (Oncorhynchus mykiss) fed with diets supplemented with U. dioica at 0, 1, 2 and 3%. After 8 weeks of feeding, the addition of U. dioica at 3% level resulted in improved weight gain, specific growth rate and feed conversion ratio significantly when compared to the other groups (P nettle when measured after 4 weeks; while, total red blood cells, white blood, Htc, Hb, lymphocyte and neutrophil populations significantly increased after 8 weeks in the same group (P nettle at 3% when compared to the other groups after 8 weeks; however, triglycerides decreased significantly in the same group on the 4th and 8th week (P nettle supplementation exhibited improved antagonistic activities against several bacterial pathogens (Streptococcus iniae, Yersinia ruckeri, Vibrio anguillarum and Lactococcus garviae), skin mucus enzymes activities (alkaline phosphatase, lysozyme, protease and esterase) and protein levels in 2 and 3% groups with the highest being in case of 3% group when compared to the other groups (P nettle. The present findings demonstrated that dietary administration of U. dioica enhanced growth and stimulated fish immunity; thus, enabling the fish to be more resistant against bacterial infections. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Effects of in vivo chronic exposure to pendimethalin on EROD activity and antioxidant defenses in rainbow trout (Oncorhynchus mykiss).

    Science.gov (United States)

    Danion, Morgane; Le Floch, Stéphane; Lamour, François; Quentel, Claire

    2014-01-01

    Pendimethalin, an herbicide active substance frequently used in terrestrial systems, has detected in European aquatic ecosystems. Reliable indicators still need to be found in order to properly assess the impact of pesticides in fish. After an in vivo chronic exposure to pendimethalin, the detoxification process and the antioxidant defense system were assessed in 120 adult rainbow trout, Oncorhynchus mykiss. Four nominal exposure conditions were tested: control (C), 500 ng L(-1) (P500), 800 ng L(-1) (P800) and the commercial formulation Prowl(®) at 500 ng L(-1) (Pw500). Fish samples were made after a 28 day exposure period (D28) and after a fifteen day recovery period in clean fresh water (D43). At D28, ethoxyresorufin-O-deethylase (EROD) activity was not activated in liver in spite of the pendimethalin uptake in fish. At D43, EROD activity in fish exposed to the commercial product was lower than in control fish, which may be explained by the high presence of herbicide in fish (613±163 ng g bile(-1)). Furthermore, antioxidant defense responses were set up by trout in gills and liver following chronic exposure to 800 ng L(-1) of pendimethalin concentration. While the glutathione content (GSH) decreased in gills, it increased in liver associated with higher activities of glutathione peroxidase (GPx) and superoxide dismutase (SOD). These disturbances could lead to reactive oxygen species production and oxidative stress in the vital organs in fish. After fifteen days in clean water, while the SOD activity was restored, the GSH content and GPx activity were still significantly disturbed in fish exposed to pendimethalin in comparison with control. These significant differences between treatments in antioxidant defenses parameters measured, attesting to the irreversibility of the effects. © 2013 Published by Elsevier Inc.

  20. Molecular dosimetry of DNA adducts in rainbow trout (Oncorhynchus mykiss) exposed to benzo(a)pyrene by different routes

    International Nuclear Information System (INIS)

    Potter, D.; Clarius, T.M.; Wright, A.S.; Watson, W.P.

    1994-01-01

    Farm raised rainbow trout (Oncorhynchus mykiss) were exposed by various routes to benzo(a)pyrene (BP) as a representative carcinogenic polycyclic aromatic hydrocarbon (PAH). Following exposure of fish to the chemical by intraperitoneal (i.p.) injection, 32 P-postlabelling studies indicated that non-feral trout were relatively resistant to the formation of BP-DNA adducts in liver. No adducts were detected in fish exposed to single doses (20 mg/kg) of BP. Multiple exposures (e.g. 2 x 25 mg/kg) were necessary in order for adducts to be detected, indicating that induction of the metabolising enzymes required for the bioactivation of BP is necessary. These studies provided reference information on DNA adducts for comparison with data from subsequent experiments at environmentally realistic low level exposures. Two types of low level aquatic exposure were carried out. The first procedure exposed fish for 30 days to a nominally constant low level (1.2 and 0.4 μg/l) of a homogeneous dispersion of BP in water, to simulate low level aquatic environmental exposures. Following 32 P-postlabelling analysis of the liver DNA of exposed fish, BP-DNA adducts were not detected. In the second procedure, fish were exposed to a constant low level of BP (ca. 0.5 μg/l) for 15 days then to a pulse (60 μg/l) which was allowed to naturally decline (to ca. 2 μg/l) during a further 15 days. Following this exposure, significant levels of BP-DNA adducts were detected in livers of trout. The effect of dietary exposures was investigated by feeding trout a diet containing either 58 μg or 288 μg BP per day for 6 days, equivalent to total doses of 43 mg/kg and 216 mg/kg. In both cases BP-DNA adducts were detected in livers of exposed fish. The results provide useful information on the types of exposures to PAHs which may pose a genotoxic risk to fish in the environment. (orig.)

  1. Cytokine modulation by stress hormones and antagonist specific hormonal inhibition in rainbow trout (Oncorhynchus mykiss) and gilthead sea bream (Sparus aurata) head kidney primary cell culture.

    Science.gov (United States)

    Khansari, Ali Reza; Parra, David; Reyes-López, Felipe E; Tort, Lluís

    2017-09-01

    A tight interaction between endocrine and immune systems takes place mainly due to the key role of head kidney in both hormone and cytokine secretion, particularly under stress situations in which the physiological response promotes the synthesis and release of stress hormones which may lead into immunomodulation as side effect. Although such interaction has been previously investigated, this study evaluated for the first time the effect of stress-associated hormones together with their receptor antagonists on the expression of cytokine genes in head kidney primary cell culture (HKPCC) of the freshwater rainbow trout (Oncorhynchus mykiss) and the seawater gilthead sea bream (Sparus aurata). The results showed a striking difference when comparing the response obtained in trout and seabream. Cortisol and adrenocorticotropic hormone (ACTH) decreased the expression of immune-related genes in sea bream but not in rainbow trout and this cortisol effect was reverted by the antagonist mifepristone but not spironolactone. On the other hand, while adrenaline reduced the expression of pro-inflammatory cytokines (IL-1β, IL-6) in rainbow trout, the opposite effect was observed in sea bream showing an increased expression (IL-1β, IL-6). Interestingly, this effect was reverted by antagonist propranolol but not phentolamine. Overall, our results confirm the regional interaction between endocrine and cytokine messengers and a clear difference in the sensitivity to the hormonal stimuli between the two species. Copyright © 2017 Elsevier Inc. All rights reserved.

  2. Transcriptome analysis provides insights into hepatic responses to moderate heat stress in the rainbow trout (Oncorhynchus mykiss).

    Science.gov (United States)

    Li, Yongjuan; Huang, Jinqiang; Liu, Zhe; Zhou, Yanjing; Xia, Binpeng; Wang, Yongjie; Kang, Yujun; Wang, Jianfu

    2017-07-01

    The rainbow trout is an economically important fish in the world. The limited stress tolerance of this species to high summer-like temperatures usually leads to mass mortality and great economic loss. However, there is limited information on the mechanisms underlying moderate heat responses in the liver of the rainbow trout. Here, we performed transcriptome profiling of rainbow trout liver under moderate heat stress by using the Hiseq™ 4000 sequencing platform. More than 277 million clean reads were obtained from 6 libraries and aligned against the rainbow trout genome. A total of 128 unique transcripts were differentially expressed in the liver under heat-stress and control conditions, many heat shock protein genes for thermoregulation and some novel genes involved in heat stress were identified. Nine of the differently expressed genes were further validated by qRT-PCR. Gene ontology and Kyoto Encyclopedia of Genes and Genomes analyses revealed that several pathways, including those for protein metabolism, energy metabolism, and immune system, were influenced by heat stress. Moreover, an important protein-processing pathway in the endoplasmic reticulum (ER) was identified, and the key role of ER-associated degradation and function of calpain as an upstream regulator of apoptosis were confirmed under heat stress. The results of this study provide a comprehensive overview of heat stress-induced transcriptional patterns in rainbow trout liver and would be particularly useful for further studies on the molecular mechanisms underlying responses to heat stress in this species. Copyright © 2017. Published by Elsevier B.V.

  3. Modulation of cadmium-induced mitochondrial dysfunction and volume changes by temperature in rainbow trout (Oncorhynchus mykiss)

    International Nuclear Information System (INIS)

    Onukwufor, John O.; Kibenge, Fred; Stevens, Don; Kamunde, Collins

    2015-01-01

    Highlights: • Interactions of Cd and temperature exacerbate mitochondrial dysfunction and enhance Cd accumulation. • Cd uptake by mitochondria occurs through the Ca uniporter. • Temperature exacerbates Cd-induced mitochondrial volume changes. • Low concentrations of Cd inhibit mitochondrial swelling. - Abstract: We investigated how temperature modulates cadmium (Cd)-induced mitochondrial bioenergetic disturbances, metal accumulation and volume changes in rainbow trout (Oncorhynchus mykiss). In the first set of experiments, rainbow trout liver mitochondrial function and Cd content were measured in the presence of complex I substrates, malate and glutamate, following exposure to Cd (0–100 μM) at three (5, 13 and 25 °C) temperatures. The second set of experiments assessed the effect of temperature on Cd-induced mitochondrial volume changes, including the underlying mechanisms, at 15 and 25 °C. Although temperature stimulated both state 3 and 4 rates of respiration, the coupling efficiency was reduced at temperature extremes due to greater inhibition of state 3 at low temperature and greater stimulation of state 4 at the high temperature. Cadmium exposure reduced the stimulatory effect of temperature on state 3 respiration but increased that on state 4, consequently exacerbating mitochondrial uncoupling. The interaction of Cd and temperature yielded different responses on thermal sensitivity of state 3 and 4 respiration; the Q 10 values for state 3 respiration increased at low temperature (5–13 °C) while those for state 4 increased at high temperature (13–25 °C). Importantly, the mitochondria accumulated more Cd at high temperature suggesting that the observed greater impairment of oxidative phosphorylation with temperature was due, at least in part, to a higher metal burden. Cadmium-induced mitochondrial volume changes were characterized by an early phase of contraction followed by swelling, with temperature changing the kinetics and intensifying

  4. Modulation of cadmium-induced mitochondrial dysfunction and volume changes by temperature in rainbow trout (Oncorhynchus mykiss)

    Energy Technology Data Exchange (ETDEWEB)

    Onukwufor, John O. [Department of Biomedical Sciences, Atlantic Veterinary College, University of Prince Edward Island, Charlottetown, PE, Canada C1A 4P3 (Canada); Kibenge, Fred [Department of Pathology and Microbiology, Atlantic Veterinary College, University of Prince Edward Island, Charlottetown, PE, Canada C1A 4P3 (Canada); Stevens, Don [Department of Biomedical Sciences, Atlantic Veterinary College, University of Prince Edward Island, Charlottetown, PE, Canada C1A 4P3 (Canada); Kamunde, Collins, E-mail: ckamunde@upei.ca [Department of Biomedical Sciences, Atlantic Veterinary College, University of Prince Edward Island, Charlottetown, PE, Canada C1A 4P3 (Canada)

    2015-01-15

    Highlights: • Interactions of Cd and temperature exacerbate mitochondrial dysfunction and enhance Cd accumulation. • Cd uptake by mitochondria occurs through the Ca uniporter. • Temperature exacerbates Cd-induced mitochondrial volume changes. • Low concentrations of Cd inhibit mitochondrial swelling. - Abstract: We investigated how temperature modulates cadmium (Cd)-induced mitochondrial bioenergetic disturbances, metal accumulation and volume changes in rainbow trout (Oncorhynchus mykiss). In the first set of experiments, rainbow trout liver mitochondrial function and Cd content were measured in the presence of complex I substrates, malate and glutamate, following exposure to Cd (0–100 μM) at three (5, 13 and 25 °C) temperatures. The second set of experiments assessed the effect of temperature on Cd-induced mitochondrial volume changes, including the underlying mechanisms, at 15 and 25 °C. Although temperature stimulated both state 3 and 4 rates of respiration, the coupling efficiency was reduced at temperature extremes due to greater inhibition of state 3 at low temperature and greater stimulation of state 4 at the high temperature. Cadmium exposure reduced the stimulatory effect of temperature on state 3 respiration but increased that on state 4, consequently exacerbating mitochondrial uncoupling. The interaction of Cd and temperature yielded different responses on thermal sensitivity of state 3 and 4 respiration; the Q{sub 10} values for state 3 respiration increased at low temperature (5–13 °C) while those for state 4 increased at high temperature (13–25 °C). Importantly, the mitochondria accumulated more Cd at high temperature suggesting that the observed greater impairment of oxidative phosphorylation with temperature was due, at least in part, to a higher metal burden. Cadmium-induced mitochondrial volume changes were characterized by an early phase of contraction followed by swelling, with temperature changing the kinetics and

  5. Exposure to waterborne Cu inhibits cutaneous Na⁺ uptake in post-hatch larval rainbow trout (Oncorhynchus mykiss).

    Science.gov (United States)

    Zimmer, Alex M; Brauner, Colin J; Wood, Chris M

    2014-05-01

    In freshwater rainbow trout (Oncorhynchus mykiss), two common responses to acute waterborne copper (Cu) exposure are reductions in ammonia excretion and Na(+) uptake at the gills, with the latter representing the likely lethal mechanism of action for Cu in adult fish. Larval fish, however, lack a functional gill following hatch and rely predominantly on cutaneous exchange, yet represent the most Cu-sensitive life stage. It is not known if Cu toxicity in larval fish occurs via the skin or gills. The present study utilized divided chambers to assess cutaneous and branchial Cu toxicity over larval development, using disruptions in ammonia excretion (Jamm) and Na(+) uptake (Jin(Na)) as toxicological endpoints. Early in development (early; 3 days post-hatch; dph), approximately 95% of Jamm and 78% of Jin(Na) occurred cutaneously, while in the late developmental stage (late; 25 dph), the gills were the dominant site of exchange (83 and 87% of Jamm and Jin(Na), respectively). Exposure to 50 μg/l Cu led to a 49% inhibition of Jamm in the late developmental stage only, while in the early and middle developmental (mid; 17 dph) stages, Cu had no effect on Jamm. Jin(Na), however, was significantly inhibited by Cu exposure at the early (53% reduction) and late (47% reduction) stages. Inhibition at the early stage of development was mediated by a reduction in cutaneous uptake, representing the first evidence of cutaneous metal toxicity in an intact aquatic organism. The inhibitions of both Jamm and Jin(Na) in the late developmental stage occurred via a reduction in branchial exchange only. The differential responses of the skin and gills to Cu exposure suggest that the mechanisms of Jamm and Jin(Na) and/or Cu toxicity differ between these tissues. Exposure to 20μg/l Cu revealed that Jamm is the more Cu-sensitive process. The results presented here have important implications in predicting metal toxicity in larval fish. The Biotic Ligand Model (BLM) is currently used to predict

  6. 17α-Ethinylestradiol (EE2) effect on global gene expression in primary rainbow trout (Oncorhynchus mykiss) hepatocytes.

    Science.gov (United States)

    Hultman, Maria T; Song, You; Tollefsen, Knut Erik

    2015-12-01

    The potential impact of endocrine disrupting chemicals (EDCs) in the aquatic environment has driven the development of screening assays to evaluate the estrogenic properties of chemicals and their effects on aquatic organisms such as fish. However, obtaining full concentration-response relationships in animal (in vivo) exposure studies are laborious, costly and unethical, hence a need for developing feasible alternative (non-animal) methods. Use of in vitro bioassays such as primary fish hepatocytes, which retain many of the native properties of the liver, has been proposed for in vitro screening of estrogen receptor (ER) agonists and antagonists. The aim of present study was to characterize the molecular mode of action (MoA) of the ER agonist 17α-ethinylestradiol (EE2) in primary rainbow trout (Oncorhynchus mykiss) hepatocytes. A custom designed salmonid 60,000-feature (60k) oligonucleotide microarray was used to characterize the potential MoAs after 48h exposure to EE2. The microarray analysis revealed several concentration-dependent gene expression alterations including classical estrogen sensitive biomarker gene expression (e.g. estrogen receptor α, vitellogenin, zona radiata). Gene Ontology (GO) analysis displayed transcriptional changes suggesting interference of cellular growth, fatty acid and lipid metabolism potentially mediated through the estrogen receptor (ER), which were proposed to be associated with modulation of genes involved in endocrine function and reproduction. Pathway analysis supported the identified GOs and revealed modulation of additional genes associated with apoptosis and cholesterol biosynthesis. Differentially expressed genes (DEGs) related to impaired lipid metabolism (e.g. peroxisome proliferator-activated receptor α and γ), growth (e.g. insulin growth factor protein 1), phase I and II biotransformation (e.g. cytochrome P450 1A, sulfotransferase, UDP-glucuronosyltransferase and glutathione S-transferase) provided additional

  7. Effects of heat stress on respiratory burst, oxidative damage and SERPINH1 (HSP47) mRNA expression in rainbow trout Oncorhynchus mykiss.

    Science.gov (United States)

    Wang, Yanni; Liu, Zhe; Li, Zhen; Shi, Haina; Kang, Yujun; Wang, Jianfu; Huang, Jinqiang; Jiang, Li

    2016-04-01

    For rainbow trout Oncorhynchus mykiss, high temperature is a major abiotic stress that limits its growth and productivity. In this study, spleen macrophage respiratory burst (RB), serum superoxide dismutase (SOD), serum malondialdehyde (MDA) and mRNA expression of the SERPINH1 (HSP47) gene in different tissues (liver, spleen, head kidney and heart) were measured in unstressed (18 °C) and heat-stressed (25 °C) fish. Spleen macrophage RB activity, serum SOD activity and MDA content all increased significantly (P mykiss. In practice, close attention should be given to temperature changes in O. mykiss production to reduce the effects of high temperature.

  8. Use of lupin, Lupinus perennis, mango, Mangifera indica, and stinging nettle, Urtica dioica, as feed additives to prevent Aeromonas hydrophila infection in rainbow trout, Oncorhynchus mykiss (Walbaum).

    Science.gov (United States)

    Awad, E; Austin, B

    2010-05-01

    Feeding rainbow trout, Oncorhynchus mykiss (Walbaum), with 1% lupin, Lupinus perennis, mango, Mangifera indica, or stinging nettle, Urtica dioica, for 14 days led to reductions in mortality after challenge with Aeromonas hydrophila. In addition, there was significant enhancement in serum bactericidal activity, respiratory burst and lysozyme activity in the treatment groups compared to the controls. Use of lupin and mango led to the highest number of red blood and white blood cells in recipient fish, with use of stinging nettle leading to the highest haematocrit and haemoglobin values; the highest value of mean corpuscular volume and haemoglobin was in the control groups and those fed with stinging nettle.

  9. The effect of oregano (Origanum vulgare) extract on prevention of S. ineae experimental infection in rainbow trout (Oncorhynchus mykiss)

    OpenAIRE

    Fakharzade, S.M.E.; Hghighi, M.; Sharif Rohani, M.; Sharifpoor, I.

    2017-01-01

    This study was performed in order to determine the effect of Oregano (Origanum vulgare) extract on Streptococcus ineae infection in rainbow trout. 063 rainbow trout weighing 15±1 gr were randomly allocated into three treatment groups with three repetition, including: 1) Control group, 2) Oregano extract treated group (1% of diet), 3) Felorfenicol treated group (10mg/kg fish), all feed one time a day for two weeks. At the end of the second week, 5 fish of each repetition collected and sampled ...

  10. Lipolysis og different oils using crude enzyme isolate from the intestinal tract of rainbow trout, Oncorhynchus mykiss

    DEFF Research Database (Denmark)

    Göttsche, J.R.; Nielsen, Nina Skall; Nielsen, Henrik Hauch

    2005-01-01

    Crude enzyme isolate was prepared from the intestine of rainbow trout. Positional specificity of the crude enzyme isolate was determined from both 1(3)- and 2-MAG products after i n vitro lipolysis of radioactive-labeled triolein. The ratio of 2- MAG/1(3)-MAG was 2:1, suggesting that the overall...... lipase specificity of the enzyme isolate from rainbow trout tended to be 1,3-specific; however, activity against the sn -2 position also was shown. In vitro lipolysis of four different unlabeled oils was performed with the crude enzyme isolate. The oils were: structured lipid [SL; containing the medium...

  11. Oral DNA vaccination of rainbow trout, Oncorhynchus mykiss (Walbaum), against infectious haematopoietic necrosis virus using PLGA [Poly(D,L-Lactic-Co-Glycolic Acid)] nanoparticles.

    Science.gov (United States)

    Adomako, M; St-Hilaire, S; Zheng, Y; Eley, J; Marcum, R D; Sealey, W; Donahower, B C; Lapatra, S; Sheridan, P P

    2012-03-01

    A DNA vaccine against infectious haematopoietic necrosis virus (IHNV) is effective at protecting rainbow trout, Oncorhynchus mykiss, against disease, but intramuscular injection is required and makes the vaccine impractical for use in the freshwater rainbow trout farming industry. Poly (D,L-lactic-co-glycolic acid) (PLGA) is a U.S. Food and Drug Administration (FDA) approved polymer that can be used to deliver DNA vaccines. We evaluated the in vivo absorption of PLGA nanoparticles containing coumarin-6 when added to a fish food pellet. We demonstrated that rainbow trout will eat PLGA nanoparticle coated feed and that these nanoparticles can be detected in the epithelial cells of the lower intestine within 96 h after feeding. We also detected low levels of gene expression and anti-IHNV neutralizing antibodies when fish were fed or intubated with PLGA nanoparticles containing IHNV G gene plasmid. A virus challenge evaluation suggested a slight increase in survival at 6 weeks post-vaccination in fish that received a high dose of the oral vaccine, but there was no difference when additional fish were challenged at 10 weeks post-vaccination. The results of this study suggest that it is possible to induce an immune response using an orally delivered DNA vaccine, but the current system needs improvement. © 2012 Blackwell Publishing Ltd.

  12. Effects of sex steroids on expression of genes regulating growth-related mechanisms in rainbow trout (Oncorhynchus mykiss).

    Science.gov (United States)

    Cleveland, Beth M; Weber, Gregory M

    2015-05-15

    Effects of a single injection of 17β-estradiol (E2), testosterone (T), or 5β-dihydrotestosterone (DHT) on expression of genes central to the growth hormone (GH)/insulin-like growth factor (IGF) axis, muscle-regulatory factors, transforming growth factor-beta (TGFβ) superfamily signaling cascade, and estrogen receptors were determined in rainbow trout (Oncorhynchus mykiss) liver and white muscle tissue. In liver in addition to regulating GH sensitivity and IGF production, sex steroids also affected expression of IGF binding proteins, as E2, T, and DHT increased expression of igfbp2b and E2 also increased expression of igfbp2 and igfbp4. Regulation of this system also occurred in white muscle in which E2 increased expression of igf1, igf2, and igfbp5b1, suggesting anabolic capacity may be maintained in white muscle in the presence of E2. In contrast, DHT decreased expression of igfbp5b1. DHT and T decreased expression of myogenin, while other muscle regulatory factors were either not affected or responded similarly for all steroid treatments. Genes within the TGFβ superfamily signaling cascade responded to steroid treatment in both liver and muscle, suggesting a regulatory role for sex steroids in the ability to transmit signals initiated by TGFβ superfamily ligands, with a greater number of genes responding in liver than in muscle. Estrogen receptors were also regulated by sex steroids, with era1 expression increasing for all treatments in muscle, but only E2- and T-treatment in liver. E2 reduced expression of erb2 in liver. Collectively, these data identify how physiological mechanisms are regulated by sex steroids in a manner that promotes the disparate effects of androgens and estrogens on growth in salmonids. Published by Elsevier Inc.

  13. Acid-base and ionic fluxes in rainbow trout (Oncorhynchus mykiss) during exposure to chloramine-T

    Energy Technology Data Exchange (ETDEWEB)

    Powell, M.D.; Perry, S.F. [Department of Biology, University of Ottawa, 30 Marie Curie Ottawa, Ontario, K1N 6N5 (Canada)

    1998-09-01

    The effects of chloramine-T and its degradation products, sodium hypochlorite (NaOCl) and para-toluenesulphonamide (pTSA), on whole body acid-base and branchial and renal ion (Na{sup +}and Cl{sup -}) fluxes were examined in rainbow trout (Oncorhynchus mykiss). Exposure to chloramine-T (3.5 h, 18 mg l{sup -1}) resulted in increases in plasma total CO{sub 2} but no coincident rise in P{sub a}CO{sub 2} or reduction in blood pH. Exposure of fish to 2, 9 or 18 mg l{sup -1} chloramine-T (3.5 h duration) resulted in a reduction in net acid uptake suggesting the development of a metabolic alkalosis. Exposure to the chloramine-T breakdown product pTSA (dissolved in DMSO) resulted in increased net acid uptake (decreased acid excretion) suggesting a metabolic acidosis. Whole body ion fluxes demonstrated increases in the losses of both Na{sup +}and Cl{sup -} with chloramine-T, NaOCl and pTSA. However, the effect of DMSO alone could not be isolated. Confirmatory studies using fish in which the urinary bladder (to allow collection of urine) and dorsal aorta (to allow injection of [{sup 14}C]polyethylene glycol 4000 ([{sup 14}C]PEG), an extracellular fluid marker) were catheterised, revealed that changes in whole body ion fluxes during chloramine-T exposure could not be explained by increased renal efflux through urine flow, glomerular filtration or renal clearance. Branchial effluxes of [{sup 14}C]PEG were not significantly affected by chloramine-T exposure suggesting that the changes in whole body ionic fluxes were caused by transcellular rather than paracellular processes. (Copyright (c) 1998 Elsevier Science B.V., Amsterdam. All rights reserved.)

  14. Acid-base and ionic fluxes in rainbow trout (Oncorhynchus mykiss) during exposure to chloramine-T

    International Nuclear Information System (INIS)

    Powell, M.D.; Perry, S.F.

    1998-01-01

    The effects of chloramine-T and its degradation products, sodium hypochlorite (NaOCl) and para-toluenesulphonamide (pTSA), on whole body acid-base and branchial and renal ion (Na + and Cl - ) fluxes were examined in rainbow trout (Oncorhynchus mykiss). Exposure to chloramine-T (3.5 h, 18 mg l -1 ) resulted in increases in plasma total CO 2 but no coincident rise in P a CO 2 or reduction in blood pH. Exposure of fish to 2, 9 or 18 mg l -1 chloramine-T (3.5 h duration) resulted in a reduction in net acid uptake suggesting the development of a metabolic alkalosis. Exposure to the chloramine-T breakdown product pTSA (dissolved in DMSO) resulted in increased net acid uptake (decreased acid excretion) suggesting a metabolic acidosis. Whole body ion fluxes demonstrated increases in the losses of both Na + and Cl - with chloramine-T, NaOCl and pTSA. However, the effect of DMSO alone could not be isolated. Confirmatory studies using fish in which the urinary bladder (to allow collection of urine) and dorsal aorta (to allow injection of [ 14 C]polyethylene glycol 4000 ([ 14 C]PEG), an extracellular fluid marker) were catheterised, revealed that changes in whole body ion fluxes during chloramine-T exposure could not be explained by increased renal efflux through urine flow, glomerular filtration or renal clearance. Branchial effluxes of [ 14 C]PEG were not significantly affected by chloramine-T exposure suggesting that the changes in whole body ionic fluxes were caused by transcellular rather than paracellular processes. (Copyright (c) 1998 Elsevier Science B.V., Amsterdam. All rights reserved.)

  15. Effects of copper, hypoxia and acute temperature shifts on mitochondrial oxidation in rainbow trout (Oncorhynchus mykiss) acclimated to warm temperature

    International Nuclear Information System (INIS)

    Sappal, Ravinder; Fast, Mark; Stevens, Don; Kibenge, Fred; Siah, Ahmed; Kamunde, Collins

    2015-01-01

    Highlights: • Warm acclimation reduced the electron transport system (ETS) efficiency. • Warm acclimation altered the effects of acute temperature shift, hypoxia and Cu on ETS. • Warm acclimation increased thermal sensitivity of state 3 and reduced that of state 4. • Cu stimulated while hypoxia inhibited ETS respiratory activity. • Interactions of Cu and hypoxia on the ETS and plasma metabolites were antagonistic. - Abstract: Temperature fluctuations, hypoxia and metals pollution frequently occur simultaneously or sequentially in aquatic systems and their interactions may confound interpretation of their biological impacts. With a focus on energy homeostasis, the present study examined how warm acclimation influences the responses and interactions of acute temperature shift, hypoxia and copper (Cu) exposure in fish. Rainbow trout (Oncorhynchus mykiss) were acclimated to cold (11 °C; control) and warm (20 °C) temperature for 3 weeks followed by exposure to environmentally realistic levels of Cu and hypoxia for 24 h. Subsequently, mitochondrial electron transport system (ETS) respiratory activity supported by complexes I–IV (CI–IV), plasma metabolites and condition indices were measured. Warm acclimation reduced fish condition, induced aerobic metabolism and altered the responses of fish to acute temperature shift, hypoxia and Cu. Whereas warm acclimation decelerated the ETS and increased the sensitivity of maximal oxidation rates of the proximal (CI and II) complexes to acute temperature shift, it reduced the thermal sensitivity of state 4 (proton leak). Effects of Cu with and without hypoxia were variable depending on the acclimation status and functional index. Notably, Cu stimulated respiratory activity in the proximal ETS segments, while hypoxia was mostly inhibitory and minimized the stimulatory effect of Cu. The effects of Cu and hypoxia were modified by temperature and showed reciprocal antagonistic interaction on the ETS and plasma

  16. Effects of copper, hypoxia and acute temperature shifts on mitochondrial oxidation in rainbow trout (Oncorhynchus mykiss) acclimated to warm temperature

    Energy Technology Data Exchange (ETDEWEB)

    Sappal, Ravinder [Department of Pathology and Microbiology, Atlantic Veterinary College, University of Prince Edward Island, Charlottetown, Prince Edward Island C1A 4P3 (Canada); Department of Biomedical Sciences, Atlantic Veterinary College, University of Prince Edward Island, Charlottetown, Prince Edward Island C1A 4P3 (Canada); Fast, Mark [Department of Pathology and Microbiology, Atlantic Veterinary College, University of Prince Edward Island, Charlottetown, Prince Edward Island C1A 4P3 (Canada); Stevens, Don [Department of Biomedical Sciences, Atlantic Veterinary College, University of Prince Edward Island, Charlottetown, Prince Edward Island C1A 4P3 (Canada); Kibenge, Fred [Department of Pathology and Microbiology, Atlantic Veterinary College, University of Prince Edward Island, Charlottetown, Prince Edward Island C1A 4P3 (Canada); Siah, Ahmed [British Columbia Centre for Aquatic Health Sciences, 871A Island Highway, Campbell River, British Columbia V9W 2C2 (Canada); Kamunde, Collins, E-mail: ckamunde@upei.ca [Department of Biomedical Sciences, Atlantic Veterinary College, University of Prince Edward Island, Charlottetown, Prince Edward Island C1A 4P3 (Canada)

    2015-12-15

    Highlights: • Warm acclimation reduced the electron transport system (ETS) efficiency. • Warm acclimation altered the effects of acute temperature shift, hypoxia and Cu on ETS. • Warm acclimation increased thermal sensitivity of state 3 and reduced that of state 4. • Cu stimulated while hypoxia inhibited ETS respiratory activity. • Interactions of Cu and hypoxia on the ETS and plasma metabolites were antagonistic. - Abstract: Temperature fluctuations, hypoxia and metals pollution frequently occur simultaneously or sequentially in aquatic systems and their interactions may confound interpretation of their biological impacts. With a focus on energy homeostasis, the present study examined how warm acclimation influences the responses and interactions of acute temperature shift, hypoxia and copper (Cu) exposure in fish. Rainbow trout (Oncorhynchus mykiss) were acclimated to cold (11 °C; control) and warm (20 °C) temperature for 3 weeks followed by exposure to environmentally realistic levels of Cu and hypoxia for 24 h. Subsequently, mitochondrial electron transport system (ETS) respiratory activity supported by complexes I–IV (CI–IV), plasma metabolites and condition indices were measured. Warm acclimation reduced fish condition, induced aerobic metabolism and altered the responses of fish to acute temperature shift, hypoxia and Cu. Whereas warm acclimation decelerated the ETS and increased the sensitivity of maximal oxidation rates of the proximal (CI and II) complexes to acute temperature shift, it reduced the thermal sensitivity of state 4 (proton leak). Effects of Cu with and without hypoxia were variable depending on the acclimation status and functional index. Notably, Cu stimulated respiratory activity in the proximal ETS segments, while hypoxia was mostly inhibitory and minimized the stimulatory effect of Cu. The effects of Cu and hypoxia were modified by temperature and showed reciprocal antagonistic interaction on the ETS and plasma

  17. The polycyclic aromatic hydrocarbons benzo[a]pyrene and phenanthrene inhibit intestinal lipase activity in rainbow trout (Oncorhynchus mykiss).

    Science.gov (United States)

    de Gelder, Stefan; Sæle, Øystein; de Veen, Bas T H; Vos, Joëlle; Flik, Gert; Berntssen, Marc H G; Klaren, Peter H M

    2017-08-01

    Elevated levels of polycyclic aromatic hydrocarbons (PAHs) are detected in aquafeeds where fish oils are (partially) replaced by vegetable oils. The highly lipophilic PAHs solubilize readily in oil droplets and micelles in the intestinal lumen that can affect enzymatic lipid digestion by altering lipase activity. We therefore investigated the effect of two PAHs, benzo[a]pyrene (BaP) and phenanthrene (PHE), on bile salt-activated lipase (BAL) activity in desalted luminal extracts of the proximal intestine of rainbow trout (Oncorhynchus mykiss) using the triacylglycerides rapeseed oil and fish oil as substrates. The hydrolysis of rapeseed oil and fish oil measured at a calculated substrate concentration of 2.2mM, increased linearly up to 30min at 15°C. Substrate dependency under initial velocity conditions was described by simple Michaelis-Menten kinetics with a K m value of 1.2mM for rapeseed and fish oil. Rapeseed oil hydrolysis was inhibited by 1nM BaP and 10nM PHE. The hydrolysis of fish oil was only inhibited by 10μM BaP. The in vitro lipase activity data were corroborated by TLC/HPLC analysis of the reaction products, showing that in the presence of BaP and PHE, 46-80% less free fatty acids (FFA) were hydrolysed from rapeseed and fish oil triacylglycerides. The presence of low concentrations of BaP and PHE decreased rapeseed oil hydrolysis by BAL whereas fish oil hydrolysis was not affected. The replacement of fish oil by rapeseed oil in aquafeeds introduces PAHs that could affect lipid digestion. Copyright © 2017 Elsevier Inc. All rights reserved.

  18. An in vitro biotic ligand model (BLM) for silver binding to cultured gill epithelia of freshwater rainbow trout (Oncorhynchus mykiss)

    International Nuclear Information System (INIS)

    Zhou Bingsheng; Nichols, Joel; Playle, Richard C.; Wood, Chris M.

    2005-01-01

    'Reconstructed' gill epithelia on filter supports were grown in primary culture from dispersed gill cells of freshwater rainbow trout (Oncorhynchus mykiss). This preparation contains both pavement cells and chloride cells, and after 7-9 days in culture, permits exposure of the apical surface to true freshwater while maintaining blood-like culture media on the basolateral surface, and exhibits a stable transepithelial resistance (TER) and transepithelial potential (TEP) under these conditions. These epithelia were used to develop a possible in vitro version of the biotic ligand model (BLM) for silver; the in vivo BLM uses short-term gill binding of the metal to predict acute silver toxicity as a function of freshwater chemistry. Radio-labeled silver ( 110m Ag as AgNO 3 ) was placed on the apical side (freshwater), and the appearance of 110m Ag in the epithelia (binding) and in the basolateral media (flux) over 3 h were monitored. Silver binding (greater than the approximate range 0-100 μg l -1 ) and silver flux were concentration-dependent with a 50% saturation point (apparent K d ) value of about 10 μg l -1 or 10 -7 M, very close to the 96-h LC50 in vivo in the same water chemistry. There were no adverse effects of silver on TER, TEP, or Na + , K + -ATPase activity, though the latter declined over longer exposures, as in vivo. Silver flux over 3 h was small ( + and dissolved organic carbon (humic acid) concentrations, increased by elevations in freshwater Cl - and reductions in pH, and insensitive to elevations in Ca 2+ . With the exception of the pH response, these effects were qualitatively and quantitatively similar to in vivo BLM responses. The results suggest that an in vitro BLM approach may provide a simple and cost-effective way for evaluating the protective effects of site-specific waters

  19. Effects of dietary administration of yarrow extract on growth performance and blood biochemical parameters of rainbow trout (Oncorhynchus mykiss

    Directory of Open Access Journals (Sweden)

    Mahmoud Nafisi Bahabadi

    2014-10-01

    Full Text Available The present study was conducted to investigate the clinical effects and possible side effects of yarrow extract (Achillea millefolium L. as feed additive on biochemical blood parameters and growth performance of rainbow trout (Oncorhynchus mykiss. Fishes were treated with 0 (control, 0.1, 0.5 and 1% of yarrow extract for 30 days. Plasma alanine aminotransferase (ALT, aspartate aminotransferase (AST, lactate dehydrogenase (LDH, alkaline phosphatase (ALP, creatine kinase (CK, peroxidase activity, total complement and lysozyme activity, glucose, total protein, triglyceride and cholesterol were measured after 15 and 30 days of yarrow treatment. There were no significant changes in the lysozyme activity and glucose levels. Total protein and globulin levels were significantly higher in the fish fed with diets enriched with 1% yarrow extract on day 30. Triglyceride and cholesterol levels was significantly decreased in the fish fed with diets containing 0.5% and 1% yarrow extract on day 30 (P<0.05. LDH, CK and peroxidase activities in the fish fed with diets having 1% yarrow extract were significantly decreased at the end of the experiment (P<0.05. In contrast, a significant increase in AST, ALP and total complement activity was observed in the fish fed with 1% yarrow extract diet, on day 15 (P<0.05. The weight gain and specific growth rate increased and food conversion ratio decreased in in the fish fed 1% yarrow extract on day 30. Condition factor in the fish fed with yarrow extract was significantly higher than control group on 30 day. In conclusion, on the basis of these results, oral administration of yarrow extract up to 0.5% have not side effect on blood biochemical and clinical parameters of fishes. However, oral administration of 1% of yarrow extract caused cytotoxicity and modifications in blood biochemical parameters of fish.

  20. Effect of modified atmosphere and vacuum packaging on TVB-N production of rainbow trout (Oncorhynchus mykiss) and carp (Cyprinus carpio) cuts

    Science.gov (United States)

    Babić Milijašević, J.; Milijašević, M.; Đinović-Stojanović, J.; Vranić, D.

    2017-09-01

    The aim of our research was to examine the influence of packaging in modified atmosphere and vacuum on the total volatile basic nitrogen (TVB-N) content in muscle of rainbow trout (Oncorhynchus mykiss) and common carp (Cyprinus carpio), as well as to determine the most suitable gas mixtures for packing of these freshwater species. Three sample groups of trout and carp cuts were investigated. The two groups were packaged in modified atmosphere with different gas ratios: 90%CO2+10%N2 (MAP 1) and 60%CO2+40%N2 (MAP 2), whereas the third group of fish cuts were vacuum packaged. During trials, the trout and carp cuts were stored in refrigerator at 3°C±0.5°C. Determination of TVB-N was performed on 1, 4, 7, 9, 12 and 14 days of storage. The obtained results indicate that the investigated mixtures of gases and vacuum had a significant influence on the values of TVB-N in trout and carp cuts. The lowest increase in TVB-N was established in trout and carp cuts packaged in MAP 1, whereas the highest increase was established in vacuum packaged cuts. Based on the obtained results, it can be concluded that the gas mixture consisting of 90% CO2 and 10% N2 was the most suitable for packaging of fresh trout and carp cuts in terms of TVB-N value.

  1. A comparative assessment of the adrenotoxic effects of cadmium in two teleost species, rainbow trout, Oncorhynchus mykiss, and yellow perch, Perca flavescens

    Energy Technology Data Exchange (ETDEWEB)

    Lacroix, Alexandra; Hontela, Alice

    2004-03-30

    Rainbow trout (Oncorhynchus mykiss) and yellow perch (Perca flavescens) have a different sensitivity to cadmium (Cd) in vivo (trouttrout and perch, to compare the sensitivity of adrenal steroidogenesis in these two teleosts. Adrenocortical cells were exposed to Cd for 60 min, then stimulated with ACTH, dbcAMP or with pregnenolone, a cortisol precursor. Cd inhibited ACTH-stimulated cortisol secretion in a dose-dependent manner in both fish species, however, the EC50s (concentration resulting in 50% inhibition of cortisol secretion) was significantly lower in trout (EC50=0.09 mM) than perch (EC50=0.26 mM). To test the specificity of Cd to act as an endocrine disrupter, the LC50 (concentration that kills 50% of the cells) was also evaluated to determine the LC50/EC50 ratio (LC50/EC50{sub O.mykiss}=175.6>LC50/EC50{sub P.flavescens}=37.7). Adrenocortical cells of trout were more sensitive than those of perch and Cd had a higher endocrine-disrupting potential and specificity in trout than in perch. However, in both species, Cd had the same effect on ACTH, dbcAMP and pregnenolone-stimulated cortisol secretion, with pregnenolone maintaining cortisol secretion until cell viability was impaired. These results confirm that for both species, Cd interferes in the signalling pathway of cortisol synthesis in a step prior to the pregnenolone formation. Data provided by the present study revealed important differences in vulnerability of adrenal steroidogenesis between rainbow trout and yellow perch.

  2. Growth performance and antioxidant enzyme activities in rainbow trout (Oncorhynchus mykiss) juveniles fed diets supplemented with sage, mint and thyme oils.

    Science.gov (United States)

    Sönmez, Adem Yavuz; Bilen, Soner; Alak, Gonca; Hisar, Olcay; Yanık, Talat; Biswas, Gouranga

    2015-02-01

    This study evaluated effects of dietary supplementation of sage (Salvia officinalis), mint (Mentha spicata) and thyme (Thymus vulgaris) oils on growth performance, lipid peroxidation level (melondialdehyde, MDA) and liver antioxidant enzyme activities (superoxide dismutase, SOD; catalase, CAT; glucose-6-phosphate dehydrogenase, G6PD; glutathione reductase, GR; glutathione-S-transferase, GST and glutathione peroxidase, GPx) in rainbow trout (Oncorhynchus mykiss) juveniles. For this purpose, triplicate groups of rainbow trout were fed daily ad libitum with diets containing sage, mint and thyme oils at 500, 1,000 and 1,500 mg kg(-1) for 60 days. While weight gain percentage of fish fed the diets containing sage and thyme oils was significantly higher than the control group, that of fish fed mint oil was the lowest. Similarly, specific growth rate was found to be the highest in all groups of the sage and thyme oil feeding and the lowest in the mint groups. Moreover, feed conversion ratio was significantly higher in the mint oil administered groups. Survival rate was also significantly reduced in the fish fed the diet containing mint oil. It was observed that SOD, G6PD and GPx activities were significantly increased in liver tissues of all the treated fish groups compared to that of control diet-fed group. However, CAT, GST and GR activities were significantly decreased in experimental diet-fed fish groups at the end of the experiment. On the other hand, a significant reduction was found in MDA levels in the fish fed the diets with sage and thyme oils compared to control and mint diets on the 30th and 60th days of experiment. Overall, dietary inclusion of sage and thyme oils is effective in enhancing rainbow trout growth, reduction in MDA and least changing antioxidant enzyme activities at a low level of 500 mg kg(-1) diet, and they can be used as important feed supplements for rainbow trout production.

  3. Intravenous injection of unfunctionalized carbon-based nanomaterials confirms the minimal toxicity observed in aqueous and dietary exposures in juvenile rainbow trout (Oncorhynchus mykiss).

    Science.gov (United States)

    Boyle, David; Sutton, Paul A; Handy, Richard D; Henry, Theodore B

    2018-01-01

    Numerous ecotoxicology studies of carbon-based nanomaterials (CNMs) have been conducted in fishes; however, different approaches have been used to make CNM dispersions and dose tanks for aqueous exposures, and to prepare food containing CNMs for dietary studies. This diversity of experimental methods has led to conflicting results and difficulties in comparing studies. The objective of the present study was to evaluate intravenous injection of unfunctionalized CNMs in rainbow trout (Oncorhynchus mykiss), as a means of delivering a known internal dose, on tissue biochemistry and histopathological lesions; then, subsequently, to compare the results with our previous work on aqueous and dietary exposures of rainbow trout to CNMs. Rainbow trout were injected in the caudal vein with corn oil dispersions of 200 μg (approximately 1 μg g -1 ) of either the fullerene C 60 , single-walled carbon nanotubes (SWCNTs), or amorphous carbon black. After 96 h, injected fish were euthanized and tissue samples collected for biochemistry and histology. Histological examination of the kidney of fish injected intravenously indicated the presence of black material consistent with the injected carbon treatments. However, there were no additional lesions associated with CNM exposure compared to controls. There were also no significant changes in haematology, or ionoregulatory disturbance in blood plasma among the intravenously injected fish. Significant elevation in lipid peroxidation (thiobarbituric acid reactive substances TBARS) was detected only in kidney and spleen of fish injected with SWCNTs, but not the other carbon treatments. The elevated TBARS following injection contrasted with CNMs delivered via aqueous or dietary routes in our previous studies, suggesting that the latter exposure routes may not lead to absorption and toxicity in the internal tissues. Comparison of the effects of injected CNMs with aqueous and dietary CNMs exposures indicates that these materials are of

  4. Critical comparison of intravenous injection of TiO2 nanoparticles with waterborne and dietary exposures concludes minimal environmentally-relevant toxicity in juvenile rainbow trout Oncorhynchus mykiss

    International Nuclear Information System (INIS)

    Boyle, David; Al-Bairuty, Genan A.; Henry, Theodore B.; Handy, Richard D.

    2013-01-01

    A critical comparison of studies that have investigated tissue accumulation and toxicity of TiO 2 -NPs in fish is necessary to resolve inconsistencies. The present study used identical TiO 2 -NPs, toxicological endpoints, and fish (juvenile rainbow trout Oncorhynchus mykiss) as previous studies that investigated waterborne and dietary toxicity of TiO 2 -NPs, and conducted a critical comparison of results after intravenous caudal-vein injection of 50 μg of TiO 2 -NPs and bulk TiO 2 . Injected TiO 2 -NPs accumulated only in kidney (94% of measured Ti) and to a lesser extent in spleen; and injected bulk TiO 2 was found only in kidney. No toxicity of TiO 2 was observed in kidney, spleen, or other tissues. Critical comparison of these data with previous studies indicates that dietary and waterborne exposures to TiO 2 -NPs do not lead to Ti accumulation in internal tissues, and previous reports of minor toxicity are inconsistent or attributable to respiratory distress resulting from gill occlusion during waterborne exposure. -- Highlights: •Critical comparison of TiO 2 -NP toxicity studies in rainbow trout. •No evidence of TiO 2 -NP absorption in internal tissues. •Conclude minimal environmentally relevant toxicity of TiO 2 -NPs in rainbow trout. -- Critical evaluation of directly comparable investigations of TiO 2 -NP toxicity by waterborne, dietary, and intravenous injection exposures conclude minimal toxicity in juvenile rainbow trout

  5. Determination of digestible and metabolizable energy of fishmeal and soybean meal in rainbow trout with two different sizes (Oncorhynchus mykiss).

    Science.gov (United States)

    Allameh, Sayed Kamaleddin; Soofiani, Nasrollah Mahboobi; Pourreza, Javad

    2007-10-15

    The present research carried out to measure digestible (DE) and Metabolizable Energy (ME) for fishmeal and soybean meal in rainbow trout with two different sizes (120 and 220 g mean body weights). DE and ME are evaluation systems for feedstuffs and also, necessary for diet formulation. The fishes were maintained in metabolic chamber with single ingredient assay of feeding and chromic oxide (Cr2O3) was used as an external marker using total fecal collection method. Gross energy and chromic oxide values measured in feces, fishmeal and soybean meal. The results indicated that DE offishmeal was 3700 and 3591 kcal kg(-1) in 120 and 220 g body weight rainbow trout, respectively. Soybean meal had 3004 and 2889 kcal kg(-1) respectively. Calculated ME from DE were 3204 and 3110 kcal kg(-1) for fishmeal and 2601 and 2502 kcal kg(-1) for soybean meal in 120 and 220 g rainbow trout, respectively. The results showed that rainbow trout can utilize fishmeal more efficiently than soybean meal.

  6. Ploidy effects on genes regulating growth mechanisms during fasting and refeeding in juvenile rainbow trout (Oncorhynchus mykiss)

    Science.gov (United States)

    Diploid and triploid rainbow trout weighing approximately 3 g were either fed for five weeks, or feed deprived for one week, followed by refeeding. During feed deprivation the diploids mobilized visceral stores to a greater extent than the triploids, and during refeeding, carcass growth rate recove...

  7. 3D visualization of the initial Yersinia ruckeri infection route in rainbow trout (Oncorhynchus mykiss) by optical projection tomography

    DEFF Research Database (Denmark)

    Otani, Maki; Villumsen, Kasper Rømer; Kragelund Strøm, Helene

    2014-01-01

    , optical projection tomography (OPT), a novel three-dimensional (3D) bio-imaging technique, was applied. OPT not only enables the visualization of Y. ruckeri on mucosal surfaces but also the 3D spatial distribution in whole organs, without sectioning. Rainbow trout were infected by bath challenge exposure...

  8. Improved growth performance in rainbow trout Oncorhynchus mykiss reared at high densities is linked to increased energy retention

    DEFF Research Database (Denmark)

    Laursen, Danielle Caroline; Larsen, Bodil Katrine; Skov, Peter Vilhelm

    2015-01-01

    performance. Manipulating aggressive behaviour through density may have advantages from a practical perspective. In the present study the energetic expenditure of rainbow trout held at three densities, 25, 80 and 140 kg m(-3), were related to growth performance parameters. Measurements for growth performance...

  9. GH and IGF-I induction by passive immunization of rainbow trout Oncorhynchus mykiss Walbaum using a somatostatin 14 antibody

    Science.gov (United States)

    Inhibition of the growth axis by somatostatin was studied in juvenile rainbow trout using passive immunization with a previously isolated somatostatin antibody (antiSS-14). Upon subcutaneously injection of laying hens (Gallus domesticus) with conjugated somatostatin-14 (SS-14), the antiSS-14 was iso...

  10. Growth performance comparison of intercross-triploid, induced-triploid, and diploid female rainbow trout Oncorhynchus mykiss

    Science.gov (United States)

    Triploidy is used in rainbow trout aquaculture as a means of inducing sterility to avoid the negative impacts of gonadal maturation on growth, fillet quality, and disease resistance; and for genetic isolation. Numerous studies have shown physiological differences between triploid (3N) and diploid (...

  11. RATE AND CAPACITY OF HEPATIC MICROSOMAL RING HYDROXYLATION OF PHENOL TO HYDROQUINONE AND CATECHOL IN RAINBOW TROUT (ONCORHYNCHUS MYKISS)

    Science.gov (United States)

    Rainbow trout liver microsomes were used to study the rate of ring-hydroxylation of phenol (PH) by directly measuring the production of hydroquinone (HQ), the primary metabolite, and catechol (CAT), a secondary metabolite. An HPLC method with integrated ultroviolet (UV) and elect...

  12. Cortisol and testosterone accumulation in a low pH recirculating aquaculture system for rainbow trout (Oncorhynchus mykiss)

    NARCIS (Netherlands)

    Mota, Vasco C.; Martins, Catarina I.M.; Eding, Ep H.; Canário, Adelino V.M.; Verreth, Johan A.J.

    2017-01-01

    Steroids accumulate in recirculating aquaculture system (RAS), although explanatory factors for such accumulation are still poorly explored. This study investigated the effect of water exchange rate and pH in six replicated RAS on the concentration of the stress hormone cortisol in rainbow trout

  13. Diet type dictates the gut microbiota and the immune response against Yersinia ruckeri in rainbow trout (Oncorhynchus mykiss)

    DEFF Research Database (Denmark)

    Ingerslev, Hans-Christian; Strube, Mikael Lenz; Jørgensen, Louise von Gersdorff

    2014-01-01

    of rainbow trout. The plant-based diet gave rise to an intestinal microbiota dominated by the genera Streptococcus, Leuconostoc and Weissella from phylum Firmicutes whereas phylum Proteobacteria/Bacteroidetes/Actinobacteria dominated the community in the marine fed fish. In connection to the Y. ruckeri bath...

  14. Effect of a Peracetic Acid-Based Disinfectant on Growth, Hematology and Histology of Juvenile Rainbow Trout (Oncorhynchus mykiss

    Directory of Open Access Journals (Sweden)

    Ramtin Hushangi

    2018-02-01

    Full Text Available The effects of a peracetic acid-based disinfectant product (Aquastart® were assessed on some hematological parameters, histological aspects and skin bacterial load of rainbow trout, likewise bacterial load of the rearing tank water. A total of 180 healthy rainbow trout weighing 124.65 ± 10 g were divided into two groups, each in three replicates in flow-through tanks. First group was exposed to Aquastart at 8.9 ppm for 30 min and second group was considered as the control. The fish were then reared for 60 days prior to sampling for hematological and histological studies. The lowest bacterial load level in both water columns and trout skin were observed in the treated trout (p < 0.05. Meanwhile, no significant impact on growth performance was recorded between treated and control fish. The immunocompetent cells population size in control fish were significantly lower than treated fish (p < 0.05. Histologically, no evidence of abnormality was seen in the gills, kidney, and liver tissues of treated fish. These results showed that application of Aquastart at 8.9 ppm is safe for use in flow-through tanks farming rainbow trout.

  15. Assembling a dual purpose TaqMan-based panel of single-nucleotide polymorphism markers in rainbow trout and steelhead (Oncorhynchus mykiss) for association mapping and population genetics analysis

    DEFF Research Database (Denmark)

    Hansen, Mette H H; Young, Sewall; Jørgensen, Hanne Birgitte Hede

    2011-01-01

    We establish a TaqMan-based assay panel for genotyping single-nucleotide polymorphisms in rainbow trout and steelhead (Oncorhynchus mykiss). We develop 22 novel single-nucleotide polymorphism markers based on new steelhead sequence data and on assays from sister taxa. Additionally, we adapt 154 p...

  16. Dietary methionine level affects growth performance and hepatic gene expression of GH-IGF system and protein turnover regulators in rainbow trout (Oncorhynchus mykiss) fed plant protein-based diets

    DEFF Research Database (Denmark)

    Rolland, Marine; Dalsgaard, Anne Johanne Tang; Holm, Jorgen

    2015-01-01

    The effects of dietary level of methionine were investigated in juvenile rainbow trout (Oncorhynchus mykiss) fed five plant-based diets containing increasing content of crystalline methionine (Met), in a six week growth trial. Changes in the hepatic expression of genes related to i...

  17. The host-parasite relationship between the rainbow trout (Oncorhynchus mykiss) and the ectoparasite Argulus foliaceus (Crustacea: Branchiura): epithelial mucous cell response, cortisol and factors which may influence parasite establishment

    NARCIS (Netherlands)

    Nolan, D.T.; Salm, van der A.L.; Wendelaar Bonga, S.E.

    2000-01-01

    The effects of short-term infection with the branchurian crustacean ectoparasite Argulus foliaceus, and the fish stress hormone cortisol (which is reported to stimulate mucus discharge), were studied on the mucous cell population of the head skin of rainbow trout (Oncorhynchus mykiss). Argulus

  18. Comparing the effects of feeding a grain- or a fish meal-based diet on water quality, waste production, and rainbow trout Oncorhynchus mykiss performance within low exchange water recirculating aquaculture systems

    Science.gov (United States)

    Feeding a fish meal-free grain-based diet (GB) was compared to feeding a fish meal-based diet (FM) relative to water quality criteria, waste production, water treatment process performance, and rainbow trout Oncorhynchus mykiss performance within six replicated water recirculating aquaculture system...

  19. Lactococcus lactis subsp. tructae subsp. nov. isolated from the intestinal mucus of brown trout (Salmo trutta) and rainbow trout (Oncorhynchus mykiss).

    Science.gov (United States)

    Pérez, Tania; Balcázar, José Luis; Peix, Alvaro; Valverde, Angel; Velázquez, Encarna; de Blas, Ignacio; Ruiz-Zarzuela, Imanol

    2011-08-01

    The species Lactococcus lactis currently includes three subspecies; L. lactis subsp. lactis and L. lactis subsp. cremoris, isolated from milk sources, and L. lactis subsp. hordniae, isolated from the leafhopper Hordnia circellata. In this study, three strains, designated L105(T), I3 and L101, were isolated from the intestinal mucus of brown trout (Salmo trutta) and rainbow trout (Oncorhynchus mykiss). These strains were closely related to members of the species Lactococcus lactis. Strain L105(T) showed 99.4 % 16S rRNA gene sequence similarity to that of the type strains L. lactis subsp. lactis NCDO 604(T) and L. lactis subsp. hordniae NCDO 2181(T) and showed 99.9 % similarity to the type strain Lactococcus lactis subsp. cremoris NCDO 607(T). Analysis of two housekeeping genes, rpoB and recA, confirmed the close relationship between the novel strains and L. lactis subsp. cremoris with similarities of 99.3 and 99.7 %, respectively. The three strains could, however, be differentiated from their closest relatives on the basis of several phenotypic characteristics, as was the case for L. lactis subsp. lactis and L. lactis subsp. hordniae, which were also closely related on the basis of 16S rRNA, rpoB and recA gene sequence similarities. The strains isolated in this study represent a new subspecies, for which the name Lactococcus lactis subsp. tructae subsp. nov. is proposed. The type strain is L105(T) ( = LMG 24662(T)  = DSM 21502(T)).

  20. Respirometry increases cortisol levels in rainbow trout Oncorhynchus mykiss: implications for measurements of metabolic rate

    DEFF Research Database (Denmark)

    Murray, L.; Rennie, M. D.; Svendsen, Jon Christian

    2017-01-01

    This study aimed to assess the extent to which chasing, handling and confining Oncorhynchus mykiss to a small respirometer chamber during respirometric experiments is stressful and affects metabolic measurements. The study observed increased cortisol levels in animals tested using a chase protocol...

  1. The relationship between emergence from spawning gravel and growth in farmed rainbow trout Oncorhynchus mykiss

    DEFF Research Database (Denmark)

    Åberg Andersson, Madelene; Laursen, Danielle Caroline; SILVA, P.I.M.

    2013-01-01

    The relationship between the timing of emergence from spawning gravel and growth after emergence was investigated in farmed Oncorhynchus mykiss. A relationship between the time of emergence and growth became evident after 6 months of rearing, where individuals with an intermediate emergence time...

  2. Infection by Capriniana piscium (Buetschli, 1889) Jankovski, 1973, a cause of rainbow trout (Oncorhynchus mykiss) kill

    Czech Academy of Sciences Publication Activity Database

    Svobodová, Z.; Kolářová, J.; Dyková, Iva; Hamáčková, J.; Kouřil, J.

    2009-01-01

    Roč. 29, č. 3 (2009), s. 92-97 ISSN 0108-0288 Institutional research plan: CEZ:AV0Z60220518 Keywords : Ectocommensal ciliates * Capriniana piscium * Oncorhynchus mykiss * gill infection Subject RIV: GJ - Animal Vermins ; Diseases, Veterinary Medicine Impact factor: 0.513, year: 2009

  3. Influence of water chemistry and natural organic matter on active and passive uptake of inorganic mercury by gills of rainbow trout (Oncorhynchus mykiss)

    International Nuclear Information System (INIS)

    Klinck, Joel; Dunbar, Michael; Brown, Stephanie; Nichols, Joel; Winter, Anna; Hughes, Christopher; Playle, Richard C.

    2005-01-01

    To distinguish physiologically regulated uptake from passive uptake of inorganic Hg in fish, rainbow trout (Oncorhynchus mykiss) were exposed to inorganic Hg (0.5, 1, or 2 μM total Hg) in ion-poor water with various treatments. Addition of ions to the water (mM concentrations of Ca, K, Cl) did not consistently alter Hg accumulation by trout gills, although there was a trend to higher Hg accumulation at higher ion concentrations. The apical Ca channel blockers Verapamil and lanthanum also did not consistently affect Hg accumulation by trout gills. Pre-treatment of trout with the Na channel blocker Phenamil decreased Hg uptake by about half. These results suggest a combination of physiologically regulated and passive uptake of Hg by trout gills. Strong complexing agents of Hg (EDTA, NTA, ethylenediamine, cysteine) decreased Hg-binding by trout gills in a dose-dependent manner. From these data, a conditional equilibrium binding constant for Hg to the gills was estimated as log K Hg-gill = 18.0, representing very strong binding of Hg to the gills. This value is a first step in creating a biotic ligand model (BLM) for inorganic Hg and fish. Natural organic matter (2-10 mg C/L) also decreased Hg-binding by trout gills, although mM concentrations of Na, K, and Cl interfered with this effect. At low concentrations of these ions, natural organic matter samples isolated from various sources bound Hg to similar degrees, as judged by Hg accumulation by trout gills. A conditional binding constant to natural organic matter (NOM) was estimated as log K Hg-NOM = 18.0 with about 0.5 μmol binding sites per mg C, representing strong binding of Hg to NOM

  4. Influence of water chemistry and natural organic matter on active and passive uptake of inorganic mercury by gills of rainbow trout (Oncorhynchus mykiss)

    Energy Technology Data Exchange (ETDEWEB)

    Klinck, Joel [Department of Biology, Wilfrid Laurier University, Waterloo, Ont., N2L 3C5 (Canada); Dunbar, Michael [Department of Biology, Wilfrid Laurier University, Waterloo, Ont., N2L 3C5 (Canada); Brown, Stephanie [Department of Biology, Wilfrid Laurier University, Waterloo, Ont., N2L 3C5 (Canada); Nichols, Joel [Department of Biology, Wilfrid Laurier University, Waterloo, Ont., N2L 3C5 (Canada); Winter, Anna [Department of Biology, Wilfrid Laurier University, Waterloo, Ont., N2L 3C5 (Canada); Hughes, Christopher [Department of Biology, Wilfrid Laurier University, Waterloo, Ont., N2L 3C5 (Canada); Playle, Richard C. [Department of Biology, Wilfrid Laurier University, Waterloo, Ont., N2L 3C5 (Canada)]. E-mail: rplayle@wlu.ca

    2005-03-25

    To distinguish physiologically regulated uptake from passive uptake of inorganic Hg in fish, rainbow trout (Oncorhynchus mykiss) were exposed to inorganic Hg (0.5, 1, or 2 {mu}M total Hg) in ion-poor water with various treatments. Addition of ions to the water (mM concentrations of Ca, K, Cl) did not consistently alter Hg accumulation by trout gills, although there was a trend to higher Hg accumulation at higher ion concentrations. The apical Ca channel blockers Verapamil and lanthanum also did not consistently affect Hg accumulation by trout gills. Pre-treatment of trout with the Na channel blocker Phenamil decreased Hg uptake by about half. These results suggest a combination of physiologically regulated and passive uptake of Hg by trout gills. Strong complexing agents of Hg (EDTA, NTA, ethylenediamine, cysteine) decreased Hg-binding by trout gills in a dose-dependent manner. From these data, a conditional equilibrium binding constant for Hg to the gills was estimated as log K {sub Hg-gill} = 18.0, representing very strong binding of Hg to the gills. This value is a first step in creating a biotic ligand model (BLM) for inorganic Hg and fish. Natural organic matter (2-10 mg C/L) also decreased Hg-binding by trout gills, although mM concentrations of Na, K, and Cl interfered with this effect. At low concentrations of these ions, natural organic matter samples isolated from various sources bound Hg to similar degrees, as judged by Hg accumulation by trout gills. A conditional binding constant to natural organic matter (NOM) was estimated as log K {sub Hg-NOM} = 18.0 with about 0.5 {mu}mol binding sites per mg C, representing strong binding of Hg to NOM.

  5. Influence of water chemistry and natural organic matter on active and passive uptake of inorganic mercury by gills of rainbow trout (Oncorhynchus mykiss).

    Science.gov (United States)

    Klinck, Joel; Dunbar, Michael; Brown, Stephanie; Nichols, Joel; Winter, Anna; Hughes, Christopher; Playle, Richard C

    2005-03-25

    To distinguish physiologically regulated uptake from passive uptake of inorganic Hg in fish, rainbow trout (Oncorhynchus mykiss) were exposed to inorganic Hg (0.5, 1, or 2 microM total Hg) in ion-poor water with various treatments. Addition of ions to the water (mM concentrations of Ca, K, Cl) did not consistently alter Hg accumulation by trout gills, although there was a trend to higher Hg accumulation at higher ion concentrations. The apical Ca channel blockers Verapamil and lanthanum also did not consistently affect Hg accumulation by trout gills. Pre-treatment of trout with the Na channel blocker Phenamil decreased Hg uptake by about half. These results suggest a combination of physiologically regulated and passive uptake of Hg by trout gills. Strong complexing agents of Hg (EDTA, NTA, ethylenediamine, cysteine) decreased Hg-binding by trout gills in a dose-dependent manner. From these data, a conditional equilibrium binding constant for Hg to the gills was estimated as logK(Hg-gill) = 18.0, representing very strong binding of Hg to the gills. This value is a first step in creating a biotic ligand model (BLM) for inorganic Hg and fish. Natural organic matter (2-10 mg C/L) also decreased Hg-binding by trout gills, although mM concentrations of Na, K, and Cl interfered with this effect. At low concentrations of these ions, natural organic matter samples isolated from various sources bound Hg to similar degrees, as judged by Hg accumulation by trout gills. A conditional binding constant to natural organic matter (NOM) was estimated as logK(Hg-NOM) = 18.0 with about 0.5 micromol binding sites per mg C, representing strong binding of Hg to NOM.

  6. 17α-Ethinylestradiol (EE2) effect on global gene expression in primary rainbow trout (Oncorhynchus mykiss) hepatocytes

    International Nuclear Information System (INIS)

    Hultman, Maria T.; Song, You; Tollefsen, Knut Erik

    2015-01-01

    Highlights: • EE2 induced large scale transcriptional changes in primary hepatocytes. • Classical estrogen biomarkers were altered in a concentration-dependent manner. • EE2 altered biological processes related to lipid transport and reproduction. • EE2 interfered with lipid metabolism, biotransformation, and multidrug transport. • In vitro transcriptional changes were fairly similar to that observed in vivo. - Abstract: The potential impact of endocrine disrupting chemicals (EDCs) in the aquatic environment has driven the development of screening assays to evaluate the estrogenic properties of chemicals and their effects on aquatic organisms such as fish. However, obtaining full concentration–response relationships in animal (in vivo) exposure studies are laborious, costly and unethical, hence a need for developing feasible alternative (non-animal) methods. Use of in vitro bioassays such as primary fish hepatocytes, which retain many of the native properties of the liver, has been proposed for in vitro screening of estrogen receptor (ER) agonists and antagonists. The aim of present study was to characterize the molecular mode of action (MoA) of the ER agonist 17α-ethinylestradiol (EE2) in primary rainbow trout (Oncorhynchus mykiss) hepatocytes. A custom designed salmonid 60,000-feature (60k) oligonucleotide microarray was used to characterize the potential MoAs after 48 h exposure to EE2. The microarray analysis revealed several concentration-dependent gene expression alterations including classical estrogen sensitive biomarker gene expression (e.g. estrogen receptor α, vitellogenin, zona radiata). Gene Ontology (GO) analysis displayed transcriptional changes suggesting interference of cellular growth, fatty acid and lipid metabolism potentially mediated through the estrogen receptor (ER), which were proposed to be associated with modulation of genes involved in endocrine function and reproduction. Pathway analysis supported the identified GOs and

  7. 17α-Ethinylestradiol (EE2) effect on global gene expression in primary rainbow trout (Oncorhynchus mykiss) hepatocytes

    Energy Technology Data Exchange (ETDEWEB)

    Hultman, Maria T., E-mail: mhu@niva.no [Norwegian Institute for Water Research (NIVA), Section of Ecotoxicology and Risk Assessment, Gaustadalléen 21, N-0349 Oslo (Norway); Faculty of Environmental Science & Technology, Department for Environmental Sciences, Norwegian University of Life Sciences (NMBU), Post box 5003, N-1432 Ås (Norway); Song, You [Norwegian Institute for Water Research (NIVA), Section of Ecotoxicology and Risk Assessment, Gaustadalléen 21, N-0349 Oslo (Norway); Tollefsen, Knut Erik [Norwegian Institute for Water Research (NIVA), Section of Ecotoxicology and Risk Assessment, Gaustadalléen 21, N-0349 Oslo (Norway); Faculty of Environmental Science & Technology, Department for Environmental Sciences, Norwegian University of Life Sciences (NMBU), Post box 5003, N-1432 Ås (Norway)

    2015-12-15

    Highlights: • EE2 induced large scale transcriptional changes in primary hepatocytes. • Classical estrogen biomarkers were altered in a concentration-dependent manner. • EE2 altered biological processes related to lipid transport and reproduction. • EE2 interfered with lipid metabolism, biotransformation, and multidrug transport. • In vitro transcriptional changes were fairly similar to that observed in vivo. - Abstract: The potential impact of endocrine disrupting chemicals (EDCs) in the aquatic environment has driven the development of screening assays to evaluate the estrogenic properties of chemicals and their effects on aquatic organisms such as fish. However, obtaining full concentration–response relationships in animal (in vivo) exposure studies are laborious, costly and unethical, hence a need for developing feasible alternative (non-animal) methods. Use of in vitro bioassays such as primary fish hepatocytes, which retain many of the native properties of the liver, has been proposed for in vitro screening of estrogen receptor (ER) agonists and antagonists. The aim of present study was to characterize the molecular mode of action (MoA) of the ER agonist 17α-ethinylestradiol (EE2) in primary rainbow trout (Oncorhynchus mykiss) hepatocytes. A custom designed salmonid 60,000-feature (60k) oligonucleotide microarray was used to characterize the potential MoAs after 48 h exposure to EE2. The microarray analysis revealed several concentration-dependent gene expression alterations including classical estrogen sensitive biomarker gene expression (e.g. estrogen receptor α, vitellogenin, zona radiata). Gene Ontology (GO) analysis displayed transcriptional changes suggesting interference of cellular growth, fatty acid and lipid metabolism potentially mediated through the estrogen receptor (ER), which were proposed to be associated with modulation of genes involved in endocrine function and reproduction. Pathway analysis supported the identified GOs and

  8. Efficacy of an extract from garlic, Allium sativum, against infection with the furunculosis bacterium, Aeromonas salmonicida, in rainbow trout, Oncorhynchus mykiss

    Science.gov (United States)

    Breyer, Kate E.; Getchell, Rodman G.; Cornwell, Emily R.; Wooster, Gregory A.; Ketola, H. George; Bowser, Paul R.

    2015-01-01

    Juvenile rainbow trout, Oncorhynchus mykiss, were fed diets containing 0, 0.5, 1.0, and 2.0% of a garlic extract, challenged with a modified 50% lethal dose of Aeromonas salmonicida and monitored for 28 d. There were significant increases in survival of trout fed 0.5 and 1.0% garlic extract as compared to the control and 2.0% garlic extract groups. A target animal safety study was performed at varying increments using the target dose of 0.5% garlic extract at 0× (0% garlic extract), 1× (0.5% garlic extract), 3× (1.5% garlic extract), and 5× (2.5% garlic extract) for 3× (6 wk) the duration of the original study. There was a significant increase in the level of circulating lymphocytes and a significant decrease in the level of circulating monocytes. The latter correlated to an increased level of pigment-containing macrophage centers within the renal tissue as garlic extract dosing increased, denoting a potential deleterious inflammatory effect as macrophage infiltration became severe at the highest dose. These studies suggest that feeding low-dose (0.5% or 1.0%) garlic extract improves survivability in rainbow trout when challenged with A. salmonicida and appears safe; however, higher levels do not appear to be effective and may cause deleterious effects on health.

  9. Plasma free amino acid kinetics in rainbow trout (Oncorhynchus mykiss) using a bolus injection of 15N-labeled amino acids.

    Science.gov (United States)

    Robinson, Jacob William; Yanke, Dan; Mirza, Jeff; Ballantyne, James Stuart

    2011-02-01

    To gain insight into the metabolic design of the amino acid carrier systems in fish, we injected a bolus of (15)N amino acids into the dorsal aorta in mature rainbow trout (Oncorhynchus mykiss). The plasma kinetic parameters including concentration, pool size, rate of disappearance (R(d)), half-life and turnover rate were determined for 15 amino acids. When corrected for metabolic rate, the R(d) values obtained for trout for most amino acids were largely comparable to human values, with the exception of glutamine (which was lower) and threonine (which was higher). R(d) values ranged from 0.9 μmol 100 g(-1) h(-1) (lysine) to 22.1 μmol 100 g(-1) h(-1) (threonine) with most values falling between 2 and 6 μmol 100 g(-1) h(-1). There was a significant correlation between R(d) and the molar proportion of amino acids in rainbow trout whole body protein hydrolysate. Other kinetic parameters did not correlate significantly with whole body amino acid composition. This indicates that an important design feature of the plasma-free amino acids system involves proportional delivery of amino acids to tissues for protein synthesis.

  10. Association of a specific major histocompatibility complex class IIβ single nucleotide polymorphism with resistance to lactococcosis in rainbow trout, Oncorhynchus mykiss (Walbaum).

    Science.gov (United States)

    Colussi, S; Prearo, M; Bertuzzi, S A; Scanzio, T; Peletto, S; Favaro, L; Modesto, P; Maniaci, M G; Ru, G; Desiato, R; Acutis, P L

    2015-01-01

    Major histocompatibility complex (MHC) loci encode glycoproteins that bind to foreign peptides and initiate immune responses through their interaction with T cells. MHC class II molecules are heterodimers consisting of α and β chains encoded by extremely variable genes; variation in exon 2 is responsible for the majority of observed polymorphisms, mostly concentrated in the codons specifying the peptide-binding region. Lactococcus garvieae is the causative agent of lactococcosis, a warm-water bacterial infection pathogenic for cultured freshwater and marine fish. It causes considerable economic losses, limiting the profitability and development of fish industries in general and the intensive production of rainbow trout, Oncorhynchus mykiss (Walbaum), in particular. The disease is currently controlled with vaccines and antibiotics; however, vaccines have short-term efficacy, and increasing concerns regarding antibiotic residues have called for alternative strategies. To explore the involvement of the MHC class II β-1 domain as a candidate gene for resistance to lactococcosis, we exposed 400 rainbow trout to naturally contaminated water. One single nucleotide polymorphism (SNP) and one haplotype were associated with resistance (P trout resistant to lactococcosis. © 2014 John Wiley & Sons Ltd.

  11. The interactive effects of a gradual temperature decrease and long-term food deprivation on cardiac and hepatic blood flows in rainbow trout (Oncorhynchus mykiss).

    Science.gov (United States)

    Petersen, L H; Dzialowski, E; Huggett, D B

    2011-11-01

    The aim of the present study was to determine the extent to which the fish liver is perfused with blood. Transonic® flow probes were therefore implanted around the ventral aorta and hepatic vein(s) to record baseline blood flows in rainbow trout (Oncorhynchus mykiss) previously held under two different feeding regimes (food-deprived or fed to satiation, 8-12 weeks). Fish from both groups were exposed to a gradual temperature decrease (12°C to 5°C) and physical disturbance. Cardiac output (Q), stroke volume (Sv) and hepatic venous blood flow (HVBF) were significantly reduced in food-deprived trout at 12°C. Heart rate was not significantly affected by nutritional status, but was significantly reduced when temperature was decreased to 5°C. Physically disturbing each fish at 12°C and 5°C showed that the performance capacity of the heart was not affected by food deprivation as the capacity to increase Q and Sv was not reduced in the food-deprived group. Overall this study showed that food deprivation in rainbow trout reduced cardiac and hepatic blood flows. However, long-term food deprivation did not affect the capacity of the heart to acutely increase performance. Copyright © 2011. Published by Elsevier Inc.

  12. Evidence of sex-bias in gene expression in the brain transcriptome of two populations of rainbow trout (Oncorhynchus mykiss) with divergent life histories.

    Science.gov (United States)

    Hale, Matthew C; McKinney, Garrett J; Thrower, Frank P; Nichols, Krista M

    2018-01-01

    Sex-bias in gene expression is a mechanism that can generate phenotypic variance between the sexes, however, relatively little is known about how patterns of sex-bias vary during development, and how variable sex-bias is between different populations. To that end, we measured sex-bias in gene expression in the brain transcriptome of rainbow trout (Oncorhynchus mykiss) during the first two years of development. Our sampling included from the fry stage through to when O. mykiss either migrate to the ocean or remain resident and undergo sexual maturation. Samples came from two F1 lines: One from migratory steelhead trout and one from resident rainbow trout. All samples were reared in a common garden environment and RNA sequencing (RNA-seq) was used to estimate patterns of gene expression. A total of 1,716 (4.6% of total) genes showed evidence of sex-bias in gene expression in at least one time point. The majority (96.7%) of sex-biased genes were differentially expressed during the second year of development, indicating that patterns of sex-bias in expression are tied to key developmental events, such as migration and sexual maturation. Mapping of differentially expressed genes to the O. mykiss genome revealed that the X chromosome is enriched for female upregulated genes, and this may indicate a lack of dosage compensation in rainbow trout. There were many more sex-biased genes in the migratory line than the resident line suggesting differences in patterns of gene expression in the brain between populations subjected to different forces of selection. Overall, our results suggest that there is considerable variation in the extent and identity of genes exhibiting sex-bias during the first two years of life. These differentially expressed genes may be connected to developmental differences between the sexes, and/or between adopting a resident or migratory life history.

  13. Size-relative Effectiveness of Clove Oil as an Anaesthetic for Rainbow Trout (Oncorhynchus mykiss Walbaum, 1792 and Goldfish (Carassius auratus Linnaeus, 1758

    Directory of Open Access Journals (Sweden)

    Costas Perdikaris

    2010-01-01

    Full Text Available The purpose of this work was to investigate the size-relative effectiveness of clove oil as an anaesthetic for rainbow trout and goldfish. In total, 128 rainbow trout (Oncorhynchus mykiss (two groups of 20-23 and 30-33 cm mean fork length and 160 goldfish (Carassius auratus (four size groups of 1.5-2.5, 5-7, 11-15 and 20-25 cm were anaesthetized at different clove oil concentrations of 50, 100, 150 mg·l-1 for trouts and 75, 100, 150 mg·l-1 for goldfish. Rainbow trout exhibited total loss of balance and no response to external stimuli with shorter induction time as dosage increased (120.5 s, 64.4 s and 44.3 s, respectively. Goldfish exhibited total loss of balance and no response to external stimuli after induction time that varied with dosage used and body size of fish. The small fish (1.5-7 cm exhibited shorter induction time which ranged from 84.28 s at 75 mg·l-1 clove oil to 41.14 s at 150 mg·l-1 clove oil. The larger fish had a longer induction time inversely related to the dosage. Recovery time was longer than induction time in both species. Both species recovered within 6 min after anaesthesia at 150 mg·l-1 clove oil. Clove oil did not produce marked changes (P compared to the control. However, marked changes (P P > 0.05. For both fish species, clove oil was effective, producing minimum stress and zero mortalities, and can be recommended as an effective anaesthetic.

  14. New data on aetiology of nodular gill disease in rainbow trout, Oncorhynchus mykiss

    Czech Academy of Sciences Publication Activity Database

    Dyková, Iva; Kostka, Martin; Wortberg, F.; Nardy, E.; Pecková, Hana

    2010-01-01

    Roč. 57, č. 3 (2010), s. 157-163 ISSN 0015-5683 R&D Projects: GA ČR GA524/09/0137; GA MŠk LC522 Institutional research plan: CEZ:AV0Z60220518 Keywords : nodular gill disease * aetiological study * amoebae * Naegleria sp. * fish diseases * aquaculture * Oncorhynchus mykiss Subject RIV: GJ - Animal Vermins ; Diseases, Veterinary Medicine Impact factor: 1.533, year: 2010

  15. Evolutionary Mechanisms Involved in Emergence of Viral Haemorrhagic Septicaemia Virus (VHSV) into Cultured Rainbow Trout, Oncorhynchus mykiss

    DEFF Research Database (Denmark)

    Schönherz, Anna A.

    virulence, causing extensive losses to the aquacultre industry. Cross-species transmission and subsequent adaptation to cultured raibow trout is observed occasionally. However, the biological background facilitationg VHSV emergense has yet to be identified. In the present PhD project potential mechanisms...... facilitation VHSV emergence into cultured raibow trout were explored. In vivo infection trials and in selico based molecular analysis were performed to independently investigate the first two steps of viral emergence, namely initial introduction to- and subsequent adaptation and establishment within the new...... of genetic variation, and that VHSV emergence into cultured rainbow torut was accompanied by rapid adaptive evolution within the viral glucoprotein...

  16. How does feed with different levels of vegetable origin affect the sensory quality of ice storage Rainbow trout (Oncorhynchus mykiss)?

    DEFF Research Database (Denmark)

    Hyldig, Grethe; Nielsen, Henrik Hauch; Holm, Jørgen

    carnivores, is facing major challenges as a consequence of the limited access in future sustainable resources of wild fish or other sea living organisms from a lower trophic level for feed production. Consequently, alternative feeding regimes are now considered e.g. use of components of vegetable origin...... and methods Feed trials Rainbow trout were farmed in tanks at Biomar A/S, Hirtshals and fed on six different diets covering only marine, only vegetables and mixture of marine and vegetable feeds. Trout for the quality study were slaughtered, vacuum-packed and stored at -80°C until analysis. Sensory Quality...

  17. Identification, characterization and genetic mapping of TLR7, TLR8a1 and TLR8a2 genes in rainbow trout (Oncorhynchus mykiss)

    Science.gov (United States)

    Palti, Yniv; Gahr, Scott A.; Purcell, Maureen K.; Hadidi, Sima; Rexroad, Caird E.; Wiens, Gregory A.

    2010-01-01

    Induction of the innate immune pathways is critical for early anti-viral defense but there is limited understanding of how teleost fish recognize viral molecules and activate these pathways. In mammals, Toll-like receptors (TLR) 7 and 8 bind single-stranded RNA of viral origin and are activated by synthetic anti-viral imidazoquinoline compounds. Herein, we identify and describe the rainbow trout (Oncorhynchus mykiss) TLR7 and TLR8 gene orthologs and their mRNA expression. Two TLR7/8 loci were identified from a rainbow trout bacterial artificial chromosome (BAC) library using DNA fingerprinting and genetic linkage analyses. Direct sequencing of two representative BACs revealed intact omTLR7 and omTLR8a1 open reading frames (ORFs) located on chromosome 3 and a second locus on chromosome 22 that contains an omTLR8a2 ORF and a putative TLR7 pseudogene. We used the omTLR8a1/2 nomenclature for the two trout TLR8 genes as phylogenetic analysis revealed that they and all the other teleost TLR8 genes sequenced to date are similar to the zebrafish TLR8a, but are distinct from the zebrafish TLR8b. The duplicated trout loci exhibit conserved synteny with other fish genomes extending beyond the tandem of TLR7/8 genes. The trout TLR7 and 8a1/2 genes are composed of a single large exon similar to all other described TLR7/8 genes. The omTLR7 ORF is predicted to encode a 1049 amino acid (aa) protein with 84% similarity to the Fugu TLR7 and a conserved pattern of predicted leucine-rich repeats (LRR). The omTLR8a1 and omTLR8a2 are predicted to encode 1035- and 1034-aa proteins, respectively, and have 86% similarity to each other. omTLR8a1 is likely the ortholog of the only Atlantic salmon TLR8 gene described to date as they have 95% aa sequence similarity. The tissue expression profiles of omTLR7, omTLR8a1 and omTLR8a2 in healthy trout were highest in spleen tissue followed by anterior and then posterior kidney tissues. Rainbow trout anterior kidney leukocytes produced elevated

  18. Oxidative changes during ice storage of rainbow trout (Oncorhynchus mykiss) fed different ratios of marine and vegetable feed ingredients

    DEFF Research Database (Denmark)

    Timm Heinrich, Maike; Eymard, Sylvie; Baron, Caroline P.

    2013-01-01

    Recently fish meal and oil have increasingly been replaced with proteins and oils from vegetable sources in the diets of farmed salmonids, but the consequences for the oxidative stability of the resulting fish products have not been investigated. The aim of the present study was to evaluate...... the influence of feeding regime on composition of rainbow trout fillets, as well as on lipid and protein oxidation during storage on ice. Rainbow trout were fed six different diets, which differed in their levels of marine oil and proteins vs. vegetable oil and protein. Fish fillets were characterised...... significantly influenced fatty acid composition. Replacement of fish oil with vegetable oil reduced formation of primary oxidation products, but the effect on secondary oxidation products differed between different types of volatiles. The differences in protein and amino acid composition were not significant...

  19. An immunohistochemical study of Flexibacter psychrophilus infection in experimentally and naturally infected rainbow trout (Oncorhynchus mykiss) fry

    DEFF Research Database (Denmark)

    Evensen, O.; Lorenzen, Ellen

    1996-01-01

    An immunohistochemical method is described for the detection of Flexibacter psychrophilus in formalin-fixed, parafiin-wax-embedded fry of rainbow trout. Rabbit antiserum as well as rainbow trout hyperimmune serum were used in the study. The distribution and tissue localization of the bacterium wa...... are typically found during the chronic stage of the disease....... and experimentally infected fry showed that there was a localization of bacteria in the monocyte-macrophage system, in skin lesions, and in the retina and the choroid gland of the eye. The dermal changes included superficial or deep ulcers extending to the subcutaneous tissue or the musculature accompanied...... by inflammatory cell infiltrates in which polymorphonuclear inflammatory cells were shown to contain the bacterium in the cytoplasm by immunostaining. The eye changes were likewise a common finding in chronic cases with severe inflammatory changes in the retina and with numerous bacteria in inflammatory (mainly...

  20. Analysis of the association between spawning time QTL markers and the biannual spawning behavior in rainbow trout (Oncorhynchus mykiss

    Directory of Open Access Journals (Sweden)

    Nelson Colihueque

    2010-01-01

    Full Text Available The rainbow trout is a salmonid fish that occasionally exhibits broodstocks with biannual spawning behavior, a phenomenon known as a double annual reproductive cycle (DARC. Spawning time quantitative trait loci (SPT-QTLs affect the time of the year that female rainbow trout spawn and may influence expression of the DARC trait. In this study, microsatellite markers linked and unlinked to SPT-QTLs were genotyped to investigate the underlying genetics of this trait. SPT-QTLs influenced the DARC trait since in two case-control comparisons three linked markers (OmyFGT12TUF, One3ASC and One19ASC had significant levels of allelic frequency differentiation and marker-character association. Furthermore, alleles of One3ASC and One19ASC had significantly higher frequencies in populations that carried the DARC trait.

  1. Chronic sensitivity of white sturgeon (Acipenser transmontanus) and rainbow trout (Oncorhynchus mykiss) to cadmium, copper, lead, or zinc in laboratory water-only exposures

    Science.gov (United States)

    Wang, Ning; Ingersoll, Christopher G.; Dorman, Rebecca A.; Brumbaugh, William G.; Mebane, Christopher A.; Kunz, James L.; Hardesty, Douglas K.

    2014-01-01

    Chronic toxicity of cadmium, copper, lead, or zinc to white sturgeon (Acipenser transmontanus) and rainbow trout (Oncorhynchus mykiss) was evaluated in water-only exposures started with newly hatched larvae or approximately 1-mo-old juveniles. The 20% effect concentration (EC20) for cadmium from the sturgeon tests was higher than the EC20 from the trout tests, whereas the EC20 for copper, lead, or zinc for the sturgeon were lower than those EC20s for the trout. When the EC20s from the present study were included in compiled toxicity databases for all freshwater species, species mean chronic value for white sturgeon was in a relatively low percentile of the species sensitivity distribution for copper (9th percentile) and in the middle percentile for cadmium (55th percentile), zinc (40th percentile), or lead (50th percentile). However, the species mean chronic value for rainbow trout was in a high percentile for copper, lead, and zinc (∼68th–82nd percentile), but in a low percentile for cadmium (23rd percentile). The trout EC20s for each of the 4 metals and the sturgeon EC20s for cadmium or lead were above US Environmental Protection Agency chronic ambient water quality criteria (AWQC) or Washington State chronic water quality standards (WQS), whereas the sturgeon EC20s for copper or zinc were approximately equal to or below the chronic AWQC and WQS. In addition, acute 50% effect concentrations (EC50s) for copper obtained in the first 4 d of the chronic sturgeon test were below the final acute value used to derive acute AWQC and below acute WQS for copper.

  2. Selection for stress responsiveness and slaughter stress affect flesh quality in pan-size rainbow trout, Oncorhynchus mykiss

    OpenAIRE

    Lefevre, Florence; Cos, Isabelle; Pottinger, Tom G.; Bugeon, Jérôme

    2016-01-01

    The control of slaughter stress is of importance with regard to both fish welfare and flesh quality. Muscle characteristics and instrumentally measured quality parameters were determined in rainbow trout lines selected for high-responsiveness (HR) or low-responsiveness (LR) of plasma cortisol to an acute confinement stressor. Measurements were made in both unstressed and stressed fish (a 15 min period of confinement before slaughter) from both lines. Compared to LR fish, HR fish were smaller,...

  3. Copper and hypoxia modulate transcriptional and mitochondrial functional-biochemical responses in warm acclimated rainbow trout (Oncorhynchus mykiss)

    International Nuclear Information System (INIS)

    Sappal, Ravinder; Fast, Mark; Purcell, Sara; MacDonald, Nicole; Stevens, Don; Kibenge, Fred; Siah, Ahmed; Kamunde, Collins

    2016-01-01

    To survive in changing environments fish utilize a wide range of biological responses that require energy. We examined the effect of warm acclimation on the electron transport system (ETS) enzymes and transcriptional responses to hypoxia and copper (Cu) exposure in fish. Rainbow trout (Oncorhynchus mykiss) were acclimated to cold (11 °C; control) and warm (20 °C) temperatures for 3 weeks followed by exposure to Cu, hypoxia or both for 24 h. Activities of ETS enzyme complexes I-IV (CI–CIV) were measured in liver and gill mitochondria. Analyses of transcripts encoding for proteins involved in mitochondrial respiration (cytochrome c oxidase subunits 4-1 and 2: COX4-1 and COX4-2), metal detoxification/stress response (metallothioneins A and B: MT-A and MT-B) and energy sensing (AMP-activated protein kinase α1: AMPKα1) were done in liver mitochondria, and in whole liver and gill tissues by RT-qPCR. Warm acclimation inhibited activities of ETS enzymes while effects of Cu and hypoxia depended on the enzyme and thermal acclimation status. The genes encoding for COX4-1, COX4-2, MT-A, MT-B and AMPKα1 were strongly and tissue-dependently altered by warm acclimation. While Cu and hypoxia clearly increased MT-A and MT-B transcript levels in all tissues, their effects on COX4-1, COX4-2 and AMPKα1 mRNA levels were less pronounced. Importantly, warm acclimation differentially altered COX4-2/COX4-1 ratio in liver mitochondria and gill tissue. The three stressors showed both independent and joint actions on activities of ETS enzymes and transcription of genes involved in energy metabolism, stress response and metals homeostasis. Overall, we unveiled novel interactive effects that should not be overlooked in real world situations wherein fish normally encounter multiple stress factors. - Highlights: • Joint and individual effects of copper, hypoxia and warm acclimation differ quantitatively. • Energy metabolism genes are differentially altered by multiple stressors.

  4. Towards science-based sediment quality standards—Effects of field-collected sediments in rainbow trout (Oncorhynchus mykiss)

    Energy Technology Data Exchange (ETDEWEB)

    Brinkmann, Markus, E-mail: markus.brinkmann@bio5.rwth-aachen.de [Department of Ecosystem Analysis, Institute for Environmental Research, RWTH Aachen University, Worringerweg 1, 52074 Aachen (Germany); Eichbaum, Kathrin; Reininghaus, Mathias; Koglin, Sven [Department of Ecosystem Analysis, Institute for Environmental Research, RWTH Aachen University, Worringerweg 1, 52074 Aachen (Germany); Kammann, Ulrike [Thünen-Institute of Fisheries Ecology, Palmaille 9, 22767 Hamburg (Germany); Baumann, Lisa; Segner, Helmut [Centre for Fish and Wildlife Health, Vetsuisse Faculty, University of Bern, Länggassstr. 122, 3012 Bern (Switzerland); Zennegg, Markus [Swiss Federal Institute for Materials Science and Technology (Empa), Laboratory for Advanced Analytical Technologies, Überlandstrasse 129, 8600 Dübendorf (Switzerland); Buchinger, Sebastian; Reifferscheid, Georg [Department G3: Biochemistry, Ecotoxicology, Federal Institute of Hydrology (BFG), Am Mainzer Tor 1, 56068 Koblenz (Germany); Hollert, Henner, E-mail: henner.hollert@bio5.rwth-aachen.de [Department of Ecosystem Analysis, Institute for Environmental Research, RWTH Aachen University, Worringerweg 1, 52074 Aachen (Germany); College of Resources and Environmental Science, Chongqing University, 1 Tiansheng Road Beibei, Chongqing 400715 (China); College of Environmental Science and Engineering and State Key Laboratory of Pollution Control and Resource Reuse, Tongji University, 1239 Siping Road, Shanghai (China); State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University (China)

    2015-09-15

    Highlights: • Particle-bound DLCs were readily bioavailable during re-suspension of sediments. • DLC uptake and effects in fish were proportional to the concentration in sediments. • Responses of biomarkers reflected the contamination levels of different sediments. • Cyp1a mRNA expression and EROD activity in livers of fish responded immediately. • Histopathological lesions were strong indicators of potential long-term effects. - Abstract: Sediments can act as long-term sinks for environmental pollutants. Within the past decades, dioxin-like compounds (DLCs) such as polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), polychlorinated biphenyls (PCBs), and polycyclic aromatic hydrocarbons (PAHs) have attracted significant attention in the scientific community. To investigate the time- and concentration-dependent uptake of DLCs and PAHs in rainbow trout (Oncorhynchus mykiss) and their associated toxicological effects, we conducted exposure experiments using suspensions of three field-collected sediments from the rivers Rhine and Elbe, which were chosen to represent different contamination levels. Five serial dilutions of contaminated sediments were tested; these originated from the Prossen and Zollelbe sampling sites (both in the river Elbe, Germany) and from Ehrenbreitstein (Rhine, Germany), with lower levels of contamination. Fish were exposed to suspensions of these dilutions under semi-static conditions for 90 days. Analysis of muscle tissue by high resolution gas chromatography and mass spectrometry and of bile liquid by high-performance liquid chromatography showed that particle-bound PCDD/Fs, PCBs and PAHs were readily bioavailable from re-suspended sediments. Uptake of these contaminants and the associated toxicological effects in fish were largely proportional to their sediment concentrations. The changes in the investigated biomarkers closely reflected the different sediment contamination levels: cytochrome P450 1A m

  5. Towards science-based sediment quality standards—Effects of field-collected sediments in rainbow trout (Oncorhynchus mykiss)

    International Nuclear Information System (INIS)

    Brinkmann, Markus; Eichbaum, Kathrin; Reininghaus, Mathias; Koglin, Sven; Kammann, Ulrike; Baumann, Lisa; Segner, Helmut; Zennegg, Markus; Buchinger, Sebastian; Reifferscheid, Georg; Hollert, Henner

    2015-01-01

    Highlights: • Particle-bound DLCs were readily bioavailable during re-suspension of sediments. • DLC uptake and effects in fish were proportional to the concentration in sediments. • Responses of biomarkers reflected the contamination levels of different sediments. • Cyp1a mRNA expression and EROD activity in livers of fish responded immediately. • Histopathological lesions were strong indicators of potential long-term effects. - Abstract: Sediments can act as long-term sinks for environmental pollutants. Within the past decades, dioxin-like compounds (DLCs) such as polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), polychlorinated biphenyls (PCBs), and polycyclic aromatic hydrocarbons (PAHs) have attracted significant attention in the scientific community. To investigate the time- and concentration-dependent uptake of DLCs and PAHs in rainbow trout (Oncorhynchus mykiss) and their associated toxicological effects, we conducted exposure experiments using suspensions of three field-collected sediments from the rivers Rhine and Elbe, which were chosen to represent different contamination levels. Five serial dilutions of contaminated sediments were tested; these originated from the Prossen and Zollelbe sampling sites (both in the river Elbe, Germany) and from Ehrenbreitstein (Rhine, Germany), with lower levels of contamination. Fish were exposed to suspensions of these dilutions under semi-static conditions for 90 days. Analysis of muscle tissue by high resolution gas chromatography and mass spectrometry and of bile liquid by high-performance liquid chromatography showed that particle-bound PCDD/Fs, PCBs and PAHs were readily bioavailable from re-suspended sediments. Uptake of these contaminants and the associated toxicological effects in fish were largely proportional to their sediment concentrations. The changes in the investigated biomarkers closely reflected the different sediment contamination levels: cytochrome P450 1A m

  6. AEROMONAS SPP BACTEREMIA OF RAINBOW TROUT FRY (ONCORHYNCHUS MYKISS: BIOCHEMICAL CHARACTERIZATION OF THE CAUSATIVE ORGANISM AND ANTIMICROBIAL SUSCEPTIBILITY

    Directory of Open Access Journals (Sweden)

    Damir Kapetanović

    2004-09-01

    Full Text Available Aeromonas hydrophila and other members of Aeromonas genus are ubiquitus in aquatic environment and make part of normal bacterial flora of rainbow trout. Aeromonas spp. infections are worldwide registered. Here we present our experience and knowledge on Aeromonas bacteremia, which causes mortality of rainbow trout fry. Rainbow trout fry, 7 month old, started to die in November 2003. Fish samples (17 samples of dead and moribund fish were delivered to the Laboratory for aquaculture. With Api 20 NE tests Aeromonas hydrophila / caviae type I was identified with an average probability of 99.9 % (one test against, as well as Aeromonas hydrophila / caviae type II with an average probability of 99.5 % (one test against from liver, spleen, kidney, intestines and damaged eye. All of isolated and identified samples were tested for antibiotic susceptibility by disc diffusion method. The test showed that specimens were most sensitive on flumequin, and relatively less sensitive on chloramphenicol and enrofloxacin. Therapy was successfully applied with Flubactin®.

  7. Preparation and anatomical distribution study of 67Ga-alginic acid nanoparticles for SPECT purposes in rainbow trout (Oncorhynchus mykiss

    Directory of Open Access Journals (Sweden)

    Heidarieh Marzieh

    2014-12-01

    Full Text Available Ergosan contains 1% alginic acid extracted from two brown sea weeds. Little is known about the target organs and anatomical distribution of Ergosan (alginic acid in fish. Therefore, feasibility of developing alginic acid nanoparticles to detect target organ in rainbow trout is interesting. To make nanoparticles, Ergosan extract (alginic acid was irradiated at 30 kGy in a cobalt-60 irradiator and characterized by transmission electron microscopy (TEM and Fourier transform infrared spectroscopy (FTIR. Results from TEM images showed that particle sizes of irradiated alginic acid ranged from 30 to 70 nm. The FTIR results indicated that gamma irradiation had no significant influence on the basic structure of alginic acid. Later, alginic acid nanoparticles were successively labelled with 67Ga-gallium chloride. The biodistribution of irradiated Ergosan in normal rainbow trout showed highest uptake in intestine and kidney and then in liver and kidney at 4- and 24-h post injection, respectively. Single-photon emission computed tomography (SPECT images also demonstrated target specific binding of the tracer at 4- and 24-h post injection. In conclusion, the feed supplemented with alginic acid nanoparticles enhanced SPECT images of gastrointestinal morphology and immunity system in normal rainbow trout.

  8. Lipopolysaccharide O-antigen prevents phagocytosis of Vibrio anguillarum by rainbow trout (Oncorhynchus mykiss skin epithelial cells.

    Directory of Open Access Journals (Sweden)

    Kristoffer Lindell

    Full Text Available Colonization of host tissues is a first step taken by many pathogens during the initial stages of infection. Despite the impact of bacterial disease on wild and farmed fish, only a few direct studies have characterized bacterial factors required for colonization of fish tissues. In this study, using live-cell and confocal microscopy, rainbow trout skin epithelial cells, the main structural component of the skin epidermis, were demonstrated to phagocytize bacteria. Mutant analyses showed that the fish pathogen Vibrio anguillarum required the lipopolysaccharide O-antigen to evade phagocytosis and that O-antigen transport required the putative wzm-wzt-wbhA operon, which encodes two ABC polysaccharide transporter proteins and a methyltransferase. Pretreatment of the epithelial cells with mannose prevented phagocytosis of V. anguillarum suggesting that a mannose receptor is involved in the uptake process. In addition, the O-antigen transport mutants could not colonize the skin but they did colonize the intestines of rainbow trout. The O-antigen polysaccharides were also shown to aid resistance to the antimicrobial factors, lysozyme and polymyxin B. In summary, rainbow trout skin epithelial cells play a role in the fish innate immunity by clearing bacteria from the skin epidermis. In defense, V. anguillarum utilizes O-antigen polysaccharides to evade phagocytosis by the epithelial cells allowing it to colonize rapidly fish skin tissues.

  9. Lipopolysaccharide O-Antigen Prevents Phagocytosis of Vibrio anguillarum by Rainbow Trout (Oncorhynchus mykiss) Skin Epithelial Cells

    Science.gov (United States)

    Lindell, Kristoffer; Fahlgren, Anna; Hjerde, Erik; Willassen, Nils-Peder; Fällman, Maria; Milton, Debra L.

    2012-01-01

    Colonization of host tissues is a first step taken by many pathogens during the initial stages of infection. Despite the impact of bacterial disease on wild and farmed fish, only a few direct studies have characterized bacterial factors required for colonization of fish tissues. In this study, using live-cell and confocal microscopy, rainbow trout skin epithelial cells, the main structural component of the skin epidermis, were demonstrated to phagocytize bacteria. Mutant analyses showed that the fish pathogen Vibrio anguillarum required the lipopolysaccharide O-antigen to evade phagocytosis and that O-antigen transport required the putative wzm-wzt-wbhA operon, which encodes two ABC polysaccharide transporter proteins and a methyltransferase. Pretreatment of the epithelial cells with mannose prevented phagocytosis of V. anguillarum suggesting that a mannose receptor is involved in the uptake process. In addition, the O-antigen transport mutants could not colonize the skin but they did colonize the intestines of rainbow trout. The O-antigen polysaccharides were also shown to aid resistance to the antimicrobial factors, lysozyme and polymyxin B. In summary, rainbow trout skin epithelial cells play a role in the fish innate immunity by clearing bacteria from the skin epidermis. In defense, V. anguillarum utilizes O-antigen polysaccharides to evade phagocytosis by the epithelial cells allowing it to colonize rapidly fish skin tissues. PMID:22662189

  10. Influence of developmental stage and genotype on liver mRNA levels among wild, domesticated, and hybrid rainbow trout (Oncorhynchus mykiss).

    Science.gov (United States)

    White, Samantha L; Sakhrani, Dionne; Danzmann, Roy G; Devlin, Robert H

    2013-10-02

    Release of domesticated strains of fish into nature may pose a threat to wild populations with respect to their evolved genetic structure and fitness. Understanding alterations that have occurred in both physiology and genetics as a consequence of domestication can assist in evaluating the risks posed by introgression of domesticated genomes into wild genetic backgrounds, however the molecular causes of these consequences are currently poorly defined. The present study has examined levels of mRNA in fast-growing pure domesticated (D), slow-growing age-matched pure wild (Wa), slow-growing size-matched pure wild (Ws), and first generation hybrid cross (W/D) rainbow trout (Oncorhynchus mykiss) to investigate the influence of genotype (domesticated vs. wild, and their interactions in hybrids) and developmental stage (age- or size-matched animals) on genetic responses (i.e. dominant vs. recessive) and specific physiological pathways. Highly significant differences in mRNA levels were found between domesticated and wild-type rainbow trout genotypes (321 mRNAs), with many mRNAs in the wild-domesticated hybrid progeny showing intermediate levels. Differences were also found between age-matched and size-matched wild-type trout groups (64 mRNAs), with unique mRNA differences for each of the wild-type groups when compared to domesticated trout (Wa: 114 mRNAs, Ws: 88 mRNAs), illustrating an influence of fish developmental stage affecting findings when used as comparator groups to other genotypes. Analysis of differentially expressed mRNAs (found for both wild-type trout to domesticated comparisons) among the genotypes indicates that 34.8% are regulated consistent with an additive genetic model, whereas 39.1% and 26.1% show a recessive or dominant mode of regulation, respectively. These molecular data are largely consistent with phenotypic data (growth and behavioural assessments) assessed in domesticated and wild trout strains. The present molecular data are concordant with

  11. Reproducible methods for experimental infection with Flavobacterium psychrophilum in rainbow trout Oncorhynchus mykiss

    DEFF Research Database (Denmark)

    Madsen, Lone; Dalsgaard, Inger

    1999-01-01

    , and this method was tested using isolates with different elastin- degrading profiles and representing different serotypes. Injecting trout, average weight 1 g, with 10(4) CFU (colony- forming units) per fish caused cumulative mortalities around 60 to 70%. The virulent strains belonged to certain serotypes...... and degraded elastin. The intraperitoneal injection challenge method could be used on larger fish, but the infection dose was 10(7) CFU per fish before mortalities occurred. Bath infection and bath infection in combination with formalin treatment (stress) seemed to be reproducible methods that could be used...

  12. Purification and characterization of two chymotrypsin-like proteases from the pyloric caeca of rainbow trout oncorhynchus-mykiss

    DEFF Research Database (Denmark)

    Kristjansson, Magnus M.; Nielsen, Henrik Hauch

    1992-01-01

    Two chymotrypsins, called chymotrypsin I and II, were purified from the pyloric caeca of rainbow trout, by (NH4)2SO4 fractionation, hydrophobic interaction chromatography (phenyl-Sepharose) and ion-exchange chromatography (DEAE-Sepharose). The approximate molecular weights of chymotrypsin I and II...... unstable at pH values below 5. The amidase activity of both enzymes increased with temperature up to about 55.degree. C. Chymotrypsin I was found to be more heat stable than chymotrypsin II, an effect most likely explained by strong calcium binding of the former. The trout chymotrypsins were significantly...... more active than bovine .alpha.-chymotrypsin when assayed against Suc-AAPF-NA at 25.degree. C and casein at low temperatures (10-20.degree. C), indicating an adaptation of the activities of the trout chymotrypsins to the habitation temperatures of the fish....

  13. Effect of structured lipids based on fish oil on the growth and fatty acid composition in Rainbow Trout (Oncorhynchus mykiss)

    DEFF Research Database (Denmark)

    Nielsen, Nina Skall; Gøttsche, Jesper; Holm, Jørgen

    2005-01-01

    containing DAG. A feeding experiment where groups of rainbow trout were fed six diets containing different types of oils for 61 days was performed. The lipid fraction of the six diets was as follows: 1) Fish oil and rapeseed oil (FO diet), 2) Specific structured lipid and rapeseed oil (SL diet), 3......) Randomised structured lipids and rapeseed oil (RL diet), 4) Medium chain triglyceride and fish oil (MCT diet), 5) Diacylglycerol and fish oil (DAG diet), 6) Fish oil (FOmax diet). Five of the diets (1-5) contained mixed oils blended to contain the same amount of EPA and DHA. Three of these diets (2,3 and 4......The aim of the study was to investigate whether it was possible a) to increase the relative incorporation of n - 3 very long chain polyunsaturated fatty acids (VLCPUFA) in a low VLCPUFA diet by feeding trout structured triacylglycerols and b) to reduce fat accumulation by feeding trout a diet...

  14. Successful selection of rainbow trout (Oncorhynchus mykiss on their ability to grow with a diet completely devoid of fishmeal and fish oil, and correlated changes in nutritional traits.

    Directory of Open Access Journals (Sweden)

    Thérèse Callet

    Full Text Available In the context of limited marine resources, the exponential growth of aquaculture requires the substitution of fish oil and fishmeal, the traditional components of fish feeds by terrestrial plant ingredients. High levels of such substitution are known to negatively impact fish performance such as growth and survival in rainbow trout (Oncorhynchus mykiss as in other salmonids. In this respect, genetic selection is a key enabler for improving those performances and hence for the further sustainable development of aquaculture. We selected a rainbow trout line over three generations for its ability to survive and grow on a 100% plant-based diet devoid of both fish oil and fishmeal (V diet from the very first meal. In the present study, we compared the control line and the selected line after 3 generations of selection, both fed either the V diet or a marine resources-based diet (M diet. The objective of the study was to assess the efficiency of selection and the consequences on various correlated nutritional traits: feed intake, feed efficiency, digestibility, composition of whole fish, nutrient retention and fatty acid (FA profile. We demonstrated that the genetic variability present in our rainbow trout population can be selected to improve survival and growth. The major result of the study is that after only three generations of selection, selected fish fed the V diet grew at the same rate as the control line fed the M diet, whilst the relative reduction of body weight was 36.8% before the selection. This enhanced performance on the V diet seems to be mostly linked to a higher feed intake for the selected fish.

  15. Micro-computed tomography (μCT) as a novel method in ecotoxicology — determination of morphometric and somatic data in rainbow trout (Oncorhynchus mykiss)

    Energy Technology Data Exchange (ETDEWEB)

    Brinkmann, Markus, E-mail: markus.brinkmann@bio5.rwth-aachen.de [Department of Ecosystem Analysis, Institute for Environmental Research, RWTH Aachen University, Worringerweg 1, 52074 Aachen (Germany); Rizzo, Larissa Y.; Lammers, Twan; Gremse, Felix [Department of Experimental Molecular Imaging, Helmholtz Institute for Biomedical Engineering, RWTH Aachen University, Aachen (Germany); Schiwy, Sabrina [Department of Ecosystem Analysis, Institute for Environmental Research, RWTH Aachen University, Worringerweg 1, 52074 Aachen (Germany); Kiessling, Fabian [Department of Experimental Molecular Imaging, Helmholtz Institute for Biomedical Engineering, RWTH Aachen University, Aachen (Germany); Hollert, Henner, E-mail: henner.hollert@bio5.rwth-aachen.de [Department of Ecosystem Analysis, Institute for Environmental Research, RWTH Aachen University, Worringerweg 1, 52074 Aachen (Germany); College of Resources and Environmental Science, Chongqing University, 1 Tiansheng Road Beibei, Chongqing 400715 (China); College of Environmental Science and Engineering, State Key Laboratory of Pollution Control and Resource Reuse, Tongji University, 1239 Siping Road, Shanghai (China); State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University (China)

    2016-02-01

    Fish are important sentinel organisms for the assessment of water quality and play a central role in ecotoxicological research. Of particular importance to the assessment of health and fitness of fish stocks in response to environmental conditions or pollution are morphometric (e.g. Fulton's condition index) and somatic indices (e.g. hepatosomatic, and gonadosomatic index). Standard measurements of somatic indices are invasive and require, by definition, the sacrifice of examined animals, thus prohibiting longitudinal studies and relocation of animals captured in the field. As a potential solution, in the present study, we propose the use of micro-computed tomography (μCT) as imaging modality to non-invasively tomographically image rainbow trout (Oncorhynchus mykiss) exposed to different sediment suspensions. We here demonstrate that μCT can be used as a tool to reliably measure the volumes of different organs, which could then be applied as a substitute of their weights in calculation of somatic indices. To the best of our knowledge, this study is the first to report the results of μCT analyses in the context of ecotoxicological research in rainbow trout. It has the potential to greatly increase the information value of experiments conducted with fish and also to potentially reduce the number of animals required for studying temporal effects through facilitating longitudinal studies within the same individuals. - Highlights: • μCT was used for volumetric imaging sediment-exposed and unexposed rainbow trout • Liver volumes determined by μCT were highly correlated with liver weights. • The perfusion of organs in fish could also be studied by means of μCT. • It was shown that μCT is a useful tool in context of ecotoxicological research.

  16. Temperature Increase Negatively Affects the Fatty Acid Bioconversion Capacity of Rainbow Trout (Oncorhynchus mykiss) Fed a Linseed Oil-Based Diet.

    Science.gov (United States)

    Mellery, Julie; Geay, Florian; Tocher, Douglas R; Kestemont, Patrick; Debier, Cathy; Rollin, Xavier; Larondelle, Yvan

    2016-01-01

    Aquaculture is meant to provide fish rich in omega-3 long chain polyunsaturated fatty acids (n-3 LC-PUFA). This objective must be reached despite (1) the necessity to replace the finite and limited fish oil in feed production and (2) the increased temperature of the supply water induced by the global warming. The objective of the present paper was to determine to what extent increased water temperature influences the fatty acid bioconversion capacity of rainbow trout (Oncorhynchus mykiss) fed a plant-derived diet. Fish were fed two diets formulated with fish oil (FO) or linseed oil (LO) as only added lipid source at the optimal water temperature of 15°C or at the increased water temperature of 19°C for 60 days. We observed that a temperature increase close to the upper limit of the species temperature tolerance range negatively affected the feed efficiency of rainbow trout fed LO despite a higher feed intake. The negative impact of increased water temperature on fatty acid bioconversion capacity appeared also to be quite clear considering the reduced expression of fatty acid desaturase 2 in liver and intestine and the reduced Δ6 desaturase enzymatic activity in intestinal microsomes. The present results also highlighted a negative impact of increased temperature on the apparent in vivo enzymatic activity of Δ5 and Δ6 desaturases of fish fed LO. Interestingly, this last parameter appeared less affected than those mentioned above. This study highlights that the increased temperature that rainbow trout may face due to global warming could reduce their fatty acid bioconversion capacity. The unavoidable replacement of finite fish oil by more sustainable, readily available and economically viable alternative lipid sources in aquaculture feeds should take this undeniable environmental issue on aquaculture productivity into account.

  17. Influence of the forms and levels of dietary selenium on antioxidant status and oxidative stress-related parameters in rainbow trout (Oncorhynchus mykiss) fry.

    Science.gov (United States)

    Fontagné-Dicharry, Stéphanie; Godin, Simon; Liu, Haokun; Antony Jesu Prabhu, Philip; Bouyssière, Brice; Bueno, Maïté; Tacon, Philippe; Médale, Françoise; Kaushik, Sadasivam J

    2015-06-28

    Se is an essential micronutrient required for normal growth, development and antioxidant defence. The objective of the present study was to assess the impact of dietary Se sources and levels on the antioxidant status of rainbow trout (Oncorhynchus mykiss) fry. First-feeding fry (initial body weight: 91 mg) were fed either a plant- or fishmeal-based diet containing 0·5 or 1·2 mg Se/kg diet supplemented or not with 0·3 mg Se/kg diet supplied as Se-enriched yeast or sodium selenite for 12 weeks at 17°C. Growth and survival of rainbow trout fry were not significantly affected by dietary Se sources and levels. Whole-body Se was raised by both Se sources and to a greater extent by Se-yeast. The reduced:oxidised glutathione ratio was raised by Se-yeast, whereas other lipid peroxidation markers were not affected by dietary Se. Whole-body Se-dependent glutathione peroxidase (GPX) activity was enhanced in fish fed Se-yeast compared to fish fed sodium selenite or non-supplemented diets. Activity and gene expression of this enzyme as well as gene expression of selenoprotein P (SelP) were reduced in fish fed the non-supplemented plant-based diet. Catalase, glutamate-cysteine ligase and nuclear factor-erythroid 2-related factor 2 (Nrf2) gene expressions were reduced by Se-yeast. These results suggest the necessity to supplement plant-based diets with Se for rainbow trout fry, and highlight the superiority of organic form of Se to fulfil the dietary Se requirement and sustain the antioxidant status of fish. GPX and SelP expression proved to be good markers of Se status in fish.

  18. Micro-computed tomography (μCT) as a novel method in ecotoxicology — determination of morphometric and somatic data in rainbow trout (Oncorhynchus mykiss)

    International Nuclear Information System (INIS)

    Brinkmann, Markus; Rizzo, Larissa Y.; Lammers, Twan; Gremse, Felix; Schiwy, Sabrina; Kiessling, Fabian; Hollert, Henner

    2016-01-01

    Fish are important sentinel organisms for the assessment of water quality and play a central role in ecotoxicological research. Of particular importance to the assessment of health and fitness of fish stocks in response to environmental conditions or pollution are morphometric (e.g. Fulton's condition index) and somatic indices (e.g. hepatosomatic, and gonadosomatic index). Standard measurements of somatic indices are invasive and require, by definition, the sacrifice of examined animals, thus prohibiting longitudinal studies and relocation of animals captured in the field. As a potential solution, in the present study, we propose the use of micro-computed tomography (μCT) as imaging modality to non-invasively tomographically image rainbow trout (Oncorhynchus mykiss) exposed to different sediment suspensions. We here demonstrate that μCT can be used as a tool to reliably measure the volumes of different organs, which could then be applied as a substitute of their weights in calculation of somatic indices. To the best of our knowledge, this study is the first to report the results of μCT analyses in the context of ecotoxicological research in rainbow trout. It has the potential to greatly increase the information value of experiments conducted with fish and also to potentially reduce the number of animals required for studying temporal effects through facilitating longitudinal studies within the same individuals. - Highlights: • μCT was used for volumetric imaging sediment-exposed and unexposed rainbow trout • Liver volumes determined by μCT were highly correlated with liver weights. • The perfusion of organs in fish could also be studied by means of μCT. • It was shown that μCT is a useful tool in context of ecotoxicological research.

  19. Association between plasma antibody response and protection in rainbow trout Oncorhynchus mykiss immersion vaccinated against Yersinia ruckeri.

    Directory of Open Access Journals (Sweden)

    Martin K Raida

    Full Text Available A key hallmark of the vertebrate adaptive immune system is the generation of antigen-specific antibodies from B cells. Fish are the most primitive gnathostomes (jawed vertebrates possessing an adaptive immune system. Vaccination of rainbow trout against enteric redmouth disease (ERM by immersion in Yersinia ruckeri bacterin confers a high degree of protection to the fish. The immune mechanisms responsible for protection may comprise both cellular and humoral elements but the role of specific immunoglobulins in this system has been questioned and not previously described. The present study demonstrates significant increase in plasma antibody titers following immersion vaccination and significantly reduced mortality during Y. ruckeri challenge.Rainbow trout were immersion-vaccinated, using either a commercial ERM vaccine (AquaVac™ ERM vet or an experimental Y. ruckeri bacterin. Half of the trout vaccinated with AquaVac™ ERM vet received an oral booster (AquaVac™ ERM Oral vet. Sub-groups of the fish from each group were subsequently exposed to 1 x 10⁹ CFU Y. ruckeri/ml either eight or twenty-six weeks post vaccination (wpv. All vaccinated groups showed 0% mortality when challenged, which was highly significant compared to the non-vaccinated controls (40 and 28% mortality eight and twenty-six weeks post vaccination (wpv, respectively (P<0.0001. Plasma samples from all groups of vaccinated fish were taken 0, 4, 8, 12, 16 and 26 wpv. and Y. ruckeri specific IgM antibody levels were measured with ELISA. A significant increase in titers was recorded in vaccinated fish, which also showed a reduced bacteremia during challenge. In vitro plasma studies showed a significantly increased bactericidal effect of fresh plasma from vaccinated fish indicating that plasma proteins may play a role in protection of vaccinated rainbow trout.

  20. Microsomal biotransformation of chlorpyrifos, parathion and fenthion in rainbow trout (Oncorhynchus mykiss) and coho salmon (Oncorhynchus kisutch): mechanistic insights into interspecific differences in toxicity

    OpenAIRE

    Lavado, Ramon; Schlenk, Daniel

    2010-01-01

    Rainbow trout often serve as a surrogate species evaluating xenobiotic toxicity in cold-water species including other salmonids of the same genus, which are listed as threatened or endangered. Biotransformation tends to show species-specific patterns that influence susceptibility to xenobiotic toxicity, particularly organophoshpate insecticides (OPs). To evaluate the contribution of biotransformation in the mechanism of toxicity of three organophosphate (phosphorothionate) insecticides, chlor...

  1. Next generation sequencing for gut microbiome characterization in rainbow trout (Oncorhynchus mykiss) fed animal by-product meals as an alternative to fishmeal protein sources.

    Science.gov (United States)

    Rimoldi, Simona; Terova, Genciana; Ascione, Chiara; Giannico, Riccardo; Brambilla, Fabio

    2018-01-01

    Animal by-product meals from the rendering industry could provide a sustainable and commercially viable alternative to fishmeal (FM) in aquaculture, as they are rich in most essential amino acids and contain important amounts of water-soluble proteins that improve feed digestibility and palatability. Among them, poultry by-product meal (PBM) have given encouraging results in rainbow trout (Oncorhynchus mykiss). However, the introduction of new ingredients in the diet needs to be carefully evaluated since diet is one of the main factors affecting the gut microbiota, which is a complex community that contributes to host metabolism, nutrition, growth, and disease resistance. Accordingly, we investigated the effects of partial replacement of dietary FM with a mix of animal by-product meals and plant proteins on intestinal microbiota composition of rainbow trout in relation to growth and feeding efficiency parameters. We used 1540 trout with an initial mean body weight of 94.6 ± 14.2 g. Fish were fed for 12 weeks with 7 different feed formulations. The growth data showed that trout fed on diets rich in animal by-product meals grew as well as fish fed on control diet, which was rich in FM (37.3%) and PBM-free. High-throughput 16S rRNA gene amplicon sequencing (MiSeq platform, Illumina) was utilised to study the gut microbial community profile. After discarding Cyanobacteria (class Chloroplast) and mitochondria reads a total of 2,701,274 of reads taxonomically classified, corresponding to a mean of 96,474 ± 68,056 reads per sample, were obtained. Five thousand three hundred ninety-nine operational taxonomic units (OTUs) were identified, which predominantly mapped to the phyla of Firmicutes, Proteobacteria, Bacteroidetes and Actinobacteria. The ratio between vegetable and animal proteins proved to play a central role in determining microbiome profiles and Firmicutes and Proteobacteria phyla were particularly discriminatory for diet type in trout. Plant ingredients

  2. Next generation sequencing for gut microbiome characterization in rainbow trout (Oncorhynchus mykiss) fed animal by-product meals as an alternative to fishmeal protein sources

    Science.gov (United States)

    Rimoldi, Simona; Ascione, Chiara; Giannico, Riccardo; Brambilla, Fabio

    2018-01-01

    Animal by-product meals from the rendering industry could provide a sustainable and commercially viable alternative to fishmeal (FM) in aquaculture, as they are rich in most essential amino acids and contain important amounts of water-soluble proteins that improve feed digestibility and palatability. Among them, poultry by-product meal (PBM) have given encouraging results in rainbow trout (Oncorhynchus mykiss). However, the introduction of new ingredients in the diet needs to be carefully evaluated since diet is one of the main factors affecting the gut microbiota, which is a complex community that contributes to host metabolism, nutrition, growth, and disease resistance. Accordingly, we investigated the effects of partial replacement of dietary FM with a mix of animal by-product meals and plant proteins on intestinal microbiota composition of rainbow trout in relation to growth and feeding efficiency parameters. We used 1540 trout with an initial mean body weight of 94.6 ± 14.2 g. Fish were fed for 12 weeks with 7 different feed formulations. The growth data showed that trout fed on diets rich in animal by-product meals grew as well as fish fed on control diet, which was rich in FM (37.3%) and PBM-free. High-throughput 16S rRNA gene amplicon sequencing (MiSeq platform, Illumina) was utilised to study the gut microbial community profile. After discarding Cyanobacteria (class Chloroplast) and mitochondria reads a total of 2,701,274 of reads taxonomically classified, corresponding to a mean of 96,474 ± 68,056 reads per sample, were obtained. Five thousand three hundred ninety-nine operational taxonomic units (OTUs) were identified, which predominantly mapped to the phyla of Firmicutes, Proteobacteria, Bacteroidetes and Actinobacteria. The ratio between vegetable and animal proteins proved to play a central role in determining microbiome profiles and Firmicutes and Proteobacteria phyla were particularly discriminatory for diet type in trout. Plant ingredients

  3. Next generation sequencing for gut microbiome characterization in rainbow trout (Oncorhynchus mykiss fed animal by-product meals as an alternative to fishmeal protein sources.

    Directory of Open Access Journals (Sweden)

    Simona Rimoldi

    Full Text Available Animal by-product meals from the rendering industry could provide a sustainable and commercially viable alternative to fishmeal (FM in aquaculture, as they are rich in most essential amino acids and contain important amounts of water-soluble proteins that improve feed digestibility and palatability. Among them, poultry by-product meal (PBM have given encouraging results in rainbow trout (Oncorhynchus mykiss. However, the introduction of new ingredients in the diet needs to be carefully evaluated since diet is one of the main factors affecting the gut microbiota, which is a complex community that contributes to host metabolism, nutrition, growth, and disease resistance. Accordingly, we investigated the effects of partial replacement of dietary FM with a mix of animal by-product meals and plant proteins on intestinal microbiota composition of rainbow trout in relation to growth and feeding efficiency parameters. We used 1540 trout with an initial mean body weight of 94.6 ± 14.2 g. Fish were fed for 12 weeks with 7 different feed formulations. The growth data showed that trout fed on diets rich in animal by-product meals grew as well as fish fed on control diet, which was rich in FM (37.3% and PBM-free. High-throughput 16S rRNA gene amplicon sequencing (MiSeq platform, Illumina was utilised to study the gut microbial community profile. After discarding Cyanobacteria (class Chloroplast and mitochondria reads a total of 2,701,274 of reads taxonomically classified, corresponding to a mean of 96,474 ± 68,056 reads per sample, were obtained. Five thousand three hundred ninety-nine operational taxonomic units (OTUs were identified, which predominantly mapped to the phyla of Firmicutes, Proteobacteria, Bacteroidetes and Actinobacteria. The ratio between vegetable and animal proteins proved to play a central role in determining microbiome profiles and Firmicutes and Proteobacteria phyla were particularly discriminatory for diet type in trout. Plant

  4. Reproduction impact of mancozeb on rainbow trout (Oncorhynchus mykiss W. and accumulation of its carcinogen metabolite, ethylene thiourea in fish products

    Directory of Open Access Journals (Sweden)

    Milena TZANOVA

    2017-06-01

    Full Text Available Pesticides can be taken up from the water and accumulated in tissues of hydrobionts, often becoming multiplied thousands of times higher in the organism than in the surrounding water. The dithiocarbamate mancozeb is applied in plant protection as fungicide. In recent years the amount of mancozeb used in Europe significantly increased. It is carcinogen due to its metabolite - ethylene thiourea (ETU, which causes thyroid and pituitary tumors. The purpose of this study is to determinate the quantity of ethylene thiourea in products of rainbow trout (Oncorhynchus mykiss W., reared in environment containing permissible, according to the European law, amount of mancozeb. Seeking an answer to the question: is this concentration limit really safe for the reproduction of rainbow trout and can the more toxic metabolite - ETU, be accumulated in the fish eggs and fillet and afterwards make them harmful to the consumers? The study included 3 stages: feeding, analysis of ethylene thiourea in fish eggs and fillet by a new developed and validated HPLC (high performance liquid chromatography method and study of the reproductive indicators. The assays of ETU in all analyzed samples (fish and water were below the limit of quantification of the method, 0.05 mg*l-1, so fish do not accumulate the carcinogen degradation product of mancozeb and the maximum residue level of mancozeb is really safe for the humans as consumers. But these environmental conditions caused reproductive disorders. They can be partly compensated by using sperm activation medium for artificial insemination of trout eggs, but successful fertilization does not guarantee successful hatching, especially of eggs in trout farms with presence of mancozeb in water, even in allowable concentration. The presented results confirm previous investigation, that Salmonidae are very sensitive fish species, react to the lowest deviations in concentration levels of xenobiotics and are used for indicator of non

  5. Effect of stocking density on water quality and (Growth, Body Composition and Plasma Cortisol Content) performance of pen-reared rainbow trout ( Oncorhynchus mykiss)

    Science.gov (United States)

    Liu, Qun; Hou, Zhishuai; Wen, Haishen; Li, Jifang; He, Feng; Wang, Jinhuan; Guan, Biao; Wang, Qinglong

    2016-08-01

    The goal of the study was to examine the effect of stocking density on the water quality of culture area, as well as the growth, body composition and cortisol content of rainbow trout ( Oncorhynchus mykiss). Pen-reared trout were stocked in densities of 40, 60, 80 fish individuals m-3 (4.6, 6.6, 8.6 kg m-3, SD1, SD2 and SD3 groups, respectively) for 300 days. Compared to the water from SD1 and SD2, that from SD3 exhibited significantly higher NH 4 + -N content and COD (chemical-oxygen-demand), and a significant reduction of dissolved oxygen in day 180 (40.6 kg m-3). Stocking density was significantly associated with body weight, standard length, VSI (viscerosomatic index), CF (condition factor) and FC (food coefficient) in group SD3, particularly in day 240 and day 300 (45 or 49.3 kg m-3). Increased crude fat and decreased crude protein were displayed in high density group when the density reached to 36 kg m-3. As a cumulative effect of density-related stress, VSI, CF, FC, moisture, and crude protein content varied over time in each density group (SD1, SD2, and SD3). In summary, trout exhibited a better growth performance in low density (26.3 kg m-3) than those reared in high densities (36 and 45 kg m-3). The results indicate that rainbow trout (114.44 g ± 6.21 g, 19.69 cm ± 0.31 cm) initially stocked in 6.6 or 8.6 kg m-3 should be lightened to less than 36 kg m-3 after an intensive rearing for 240 days.

  6. Assessment of energetic costs of AhR activation by β-naphthoflavone in rainbow trout (Oncorhynchus mykiss) hepatocytes using metabolic flux analysis

    International Nuclear Information System (INIS)

    Nault, Rance; Abdul-Fattah, Hiba; Mironov, Gleb G.; Berezovski, Maxim V.; Moon, Thomas W.

    2013-01-01

    Exposure to environmental contaminants such as activators of the aryl hydrocarbon receptor (AhR) leads to the induction of defense and detoxification mechanisms. While these mechanisms allow organisms to metabolize and excrete at least some of these environmental contaminants, it has been proposed that these mechanisms lead to significant energetic challenges. This study tests the hypothesis that activation of the AhR by the model agonist β-naphthoflavone (βNF) results in increased energetic costs in rainbow trout (Oncorhynchus mykiss) hepatocytes. To address this hypothesis, we employed traditional biochemical approaches to examine energy allocation and metabolism including the adenylate energy charge (AEC), protein synthesis rates, Na + /K + -ATPase activity, and enzyme activities. Moreover, we have used for the first time in a fish cell preparation, metabolic flux analysis (MFA) an in silico approach for the estimation of intracellular metabolic fluxes. Exposure of trout hepatocytes to 1 μM βNF for 48 h did not alter hepatocyte AEC, protein synthesis, or Na + /K + -ATPase activity but did lead to sparing of glycogen reserves and changes in activities of alanine aminotransferase and citrate synthase suggesting altered metabolism. Conversely, MFA did not identify altered metabolic fluxes, although we do show that the dynamic metabolism of isolated trout hepatocytes poses a significant challenge for this type of approach which should be considered in future studies. - Highlights: • Energetic costs of AhR activation by βNF was examined in rainbow trout hepatocytes. • Metabolic flux analysis was performed on a fish cell preparation for the first time. • Exposure to βNF led to sparing of glycogen reserves and altered enzyme activities. • Adenylate energy charge was maintained despite temporal changes in metabolism

  7. Assessment of energetic costs of AhR activation by β-naphthoflavone in rainbow trout (Oncorhynchus mykiss) hepatocytes using metabolic flux analysis

    Energy Technology Data Exchange (ETDEWEB)

    Nault, Rance, E-mail: naultran@msu.edu [Ottawa-Carleton Institute of Biology, Department of Biology and Centre for Advanced Research in Environmental Genomics, University of Ottawa, Ottawa, Ontario, K1N 6N5 (Canada); Abdul-Fattah, Hiba [Ottawa-Carleton Institute of Biology, Department of Biology and Centre for Advanced Research in Environmental Genomics, University of Ottawa, Ottawa, Ontario, K1N 6N5 (Canada); Mironov, Gleb G.; Berezovski, Maxim V. [Ottawa-Carleton Institute of Biology, Department of Biology and Centre for Advanced Research in Environmental Genomics, University of Ottawa, Ottawa, Ontario, K1N 6N5 (Canada); Department of Chemistry, University of Ottawa, Ottawa, Ontario, K1N 6N5 (Canada); Moon, Thomas W. [Ottawa-Carleton Institute of Biology, Department of Biology and Centre for Advanced Research in Environmental Genomics, University of Ottawa, Ottawa, Ontario, K1N 6N5 (Canada)

    2013-08-15

    Exposure to environmental contaminants such as activators of the aryl hydrocarbon receptor (AhR) leads to the induction of defense and detoxification mechanisms. While these mechanisms allow organisms to metabolize and excrete at least some of these environmental contaminants, it has been proposed that these mechanisms lead to significant energetic challenges. This study tests the hypothesis that activation of the AhR by the model agonist β-naphthoflavone (βNF) results in increased energetic costs in rainbow trout (Oncorhynchus mykiss) hepatocytes. To address this hypothesis, we employed traditional biochemical approaches to examine energy allocation and metabolism including the adenylate energy charge (AEC), protein synthesis rates, Na{sup +}/K{sup +}-ATPase activity, and enzyme activities. Moreover, we have used for the first time in a fish cell preparation, metabolic flux analysis (MFA) an in silico approach for the estimation of intracellular metabolic fluxes. Exposure of trout hepatocytes to 1 μM βNF for 48 h did not alter hepatocyte AEC, protein synthesis, or Na{sup +}/K{sup +}-ATPase activity but did lead to sparing of glycogen reserves and changes in activities of alanine aminotransferase and citrate synthase suggesting altered metabolism. Conversely, MFA did not identify altered metabolic fluxes, although we do show that the dynamic metabolism of isolated trout hepatocytes poses a significant challenge for this type of approach which should be considered in future studies. - Highlights: • Energetic costs of AhR activation by βNF was examined in rainbow trout hepatocytes. • Metabolic flux analysis was performed on a fish cell preparation for the first time. • Exposure to βNF led to sparing of glycogen reserves and altered enzyme activities. • Adenylate energy charge was maintained despite temporal changes in metabolism.

  8. Characterisation of aroma-active and off-odour compounds in German rainbow trout (Oncorhynchus mykiss). Part I: Case of aquaculture water from earthen-ponds farming.

    Science.gov (United States)

    Mahmoud, Mohamed Ahmed Abbas; Buettner, Andrea

    2016-11-01

    Comprehensive analyses were accomplished to explore the odorous molecules responsible for off-odour development in earthen-ponds rainbow trout (Oncorhynchus mykiss) aquaculture farming in Germany. In this part of the study, water odorants were extracted using solvent-assisted flavour evaporation (SAFE); then, extracts were analysed by one- and two- dimensional high resolution gas chromatography coupled with olfactometry and mass spectrometry using two columns with different polarity (DB-FFAP and DB-5). Aroma extract dilution analysis (AEDA) of the solvent extract samples revealed 54 odorants, and 47 of them were identified. In this study, a series of compounds is described for the first time in German earthen-ponds rainbow trout aquaculture water including, amongst others, 4-hydroxy-2,5-dimethyl-3(2H)-furanone (furaneol), vanillin, (E)-4,5-epoxy-(E)-2-decenal, 4-ethyloctanoic acid, 3-methylindole (skatole), 5α-androst-16-en-3-one (androstenone), and 2-(2-butoxyethoxy) ethanol. Moreover, the sensory experiment indicated that (E)-4,5-epoxy-(E)-2-decenal, (E,E)-2,4-octadienal, and 1-octen-3-one are the main contributors to the metallic, cucumber, and mushroom notes of the samples. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. Micro-computed tomography (μCT) as a novel method in ecotoxicology--determination of morphometric and somatic data in rainbow trout (Oncorhynchus mykiss).

    Science.gov (United States)

    Brinkmann, Markus; Rizzo, Larissa Y; Lammers, Twan; Gremse, Felix; Schiwy, Sabrina; Kiessling, Fabian; Hollert, Henner

    2016-02-01

    Fish are important sentinel organisms for the assessment of water quality and play a central role in ecotoxicological research. Of particular importance to the assessment of health and fitness of fish stocks in response to environmental conditions or pollution are morphometric (e.g. Fulton's condition index) and somatic indices (e.g. hepatosomatic, and gonadosomatic index). Standard measurements of somatic indices are invasive and require, by definition, the sacrifice of examined animals, thus prohibiting longitudinal studies and relocation of animals captured in the field. As a potential solution, in the present study, we propose the use of micro-computed tomography (μCT) as imaging modality to non-invasively tomographically image rainbow trout (Oncorhynchus mykiss) exposed to different sediment suspensions. We here demonstrate that μCT can be used as a tool to reliably measure the volumes of different organs, which could then be applied as a substitute of their weights in calculation of somatic indices. To the best of our knowledge, this study is the first to report the results of μCT analyses in the context of ecotoxicological research in rainbow trout. It has the potential to greatly increase the information value of experiments conducted with fish and also to potentially reduce the number of animals required for studying temporal effects through facilitating longitudinal studies within the same individuals. Copyright © 2015 Elsevier B.V. All rights reserved.

  10. Effects of Gelatin-Based Edible Films Enriched with Laurel Essential Oil on the Quality of Rainbow Trout (Oncorhynchus mykiss Fillets During Refrigerated Storage

    Directory of Open Access Journals (Sweden)

    Tuba Baygar

    2014-01-01

    Full Text Available The effects of gelatin films enriched with laurel leaf essential oil on the quality of rainbow trout (Oncorhynchus mykiss during refrigerated storage at (4±1 °C were examined over a period of 26 days. Fish fillets were wrapped with 8 % gelatin films containing 0, 0.1 and 1 % (by volume per mass of laurel essential oil and vacuum packaged. Sensory (raw and cooked fish, microbiological (total viable counts, psychrotrophic bacteria counts, Enterobacteriaceae and lactic acid bacteria and chemical (proximate composition, pH, total volatile base nitrogen (TVB-N, thiobarbituric acid (TBA, free fatty acid (FFA and peroxide value (PV analysis, and colour measurement were carried out during the storage period and shelf-life was determined periodically. The obtained results showed that the gelatin film enriched with laurel essential oil was suitable for the preservation of rainbow trout fillet and the ability of laurel essential oil to preserve the film depended on its ratio. Combined effects of gelatin film and laurel essential oil (1 % by volume per mass was efficient in maintaining the quality characteristics at an acceptable level up to 22 days of storage, while the control and gelatin film without the essential oil reached an unacceptable level at 15 and 20 days, respectively.

  11. Determination of malachite green residues in the eggs, fry, and adult muscle-tissue of rainbow-trout (Oncorhynchus-mykiss)

    Science.gov (United States)

    Allen, John L.; Gofus, J.E.; Meinertz, Jeffery R.

    1994-01-01

    Malachite green, an effective antifungal therapeutant used in fish culture, is a known teratogen. We developed a method to simultaneously detect both the chromatic and leuco forms of malachite green residues in the eggs, fry, and adult muscle tissue of rainbow trout (oncorhynchus mykiss). Homogenates of these tissues were fortified with [c-14] malachite green chloride and extracted with 1% (v/v) acetic acid in acetonitrile or in methanol. The extracts were partitioned with chloroform, dried, redissolved in mobile phase, and analyzed by liquid chromatography (lc) with postcolumn oxidation of leuco malachite green to the chromatic form. Lc fractions were collected every 30 s for quantitation by scintillation counting. Recoveries of total [c-14] malachite green chloride residue were 85 and 98% in eggs fortified with labeled malachite green at concentrations of 0.5 And 1.00 Mug/g, respectively; 68% in fry similarly fortified at a concentration of 0.65 Mug/g; and 66% in muscle homogenate similarly fortified at a level of 1.00 Mug/g. The method was tested under operational conditions by exposing adult rainbow trout to 1.00 Mg/l [c-14] malachite green chloride bath for 1 h. Muscle samples analyzed by sample oxidation and scintillation counting contained 1.3 And 0.5 Mug/g total malachite green chloride residues immediately after exposure and after a 5-day withdrawal period, respectively.

  12. Comparative Performance Analysis of Support Vector Machine, Random Forest, Logistic Regression and k-Nearest Neighbours in Rainbow Trout (Oncorhynchus Mykiss) Classification Using Image-Based Features.

    Science.gov (United States)

    Saberioon, Mohammadmehdi; Císař, Petr; Labbé, Laurent; Souček, Pavel; Pelissier, Pablo; Kerneis, Thierry

    2018-03-29

    The main aim of this study was to develop a new objective method for evaluating the impacts of different diets on the live fish skin using image-based features. In total, one-hundred and sixty rainbow trout ( Oncorhynchus mykiss ) were fed either a fish-meal based diet (80 fish) or a 100% plant-based diet (80 fish) and photographed using consumer-grade digital camera. Twenty-three colour features and four texture features were extracted. Four different classification methods were used to evaluate fish diets including Random forest (RF), Support vector machine (SVM), Logistic regression (LR) and k -Nearest neighbours ( k -NN). The SVM with radial based kernel provided the best classifier with correct classification rate (CCR) of 82% and Kappa coefficient of 0.65. Although the both LR and RF methods were less accurate than SVM, they achieved good classification with CCR 75% and 70% respectively. The k -NN was the least accurate (40%) classification model. Overall, it can be concluded that consumer-grade digital cameras could be employed as the fast, accurate and non-invasive sensor for classifying rainbow trout based on their diets. Furthermore, these was a close association between image-based features and fish diet received during cultivation. These procedures can be used as non-invasive, accurate and precise approaches for monitoring fish status during the cultivation by evaluating diet's effects on fish skin.

  13. Comparative Performance Analysis of Support Vector Machine, Random Forest, Logistic Regression and k-Nearest Neighbours in Rainbow Trout (Oncorhynchus Mykiss Classification Using Image-Based Features

    Directory of Open Access Journals (Sweden)

    Mohammadmehdi Saberioon

    2018-03-01

    Full Text Available The main aim of this study was to develop a new objective method for evaluating the impacts of different diets on the live fish skin using image-based features. In total, one-hundred and sixty rainbow trout (Oncorhynchus mykiss were fed either a fish-meal based diet (80 fish or a 100% plant-based diet (80 fish and photographed using consumer-grade digital camera. Twenty-three colour features and four texture features were extracted. Four different classification methods were used to evaluate fish diets including Random forest (RF, Support vector machine (SVM, Logistic regression (LR and k-Nearest neighbours (k-NN. The SVM with radial based kernel provided the best classifier with correct classification rate (CCR of 82% and Kappa coefficient of 0.65. Although the both LR and RF methods were less accurate than SVM, they achieved good classification with CCR 75% and 70% respectively. The k-NN was the least accurate (40% classification model. Overall, it can be concluded that consumer-grade digital cameras could be employed as the fast, accurate and non-invasive sensor for classifying rainbow trout based on their diets. Furthermore, these was a close association between image-based features and fish diet received during cultivation. These procedures can be used as non-invasive, accurate and precise approaches for monitoring fish status during the cultivation by evaluating diet’s effects on fish skin.

  14. Microencapsulation of a putative probiotic Enterobacter species, C6-6, to protect rainbow trout, Oncorhynchus mykiss (Walbaum), against bacterial coldwater disease.

    Science.gov (United States)

    Ghosh, B; Cain, K D; Nowak, B F; Bridle, A R

    2016-01-01

    Flavobacterium psychrophilum is the causative agent of bacterial coldwater disease (BCWD), which has a major impact on salmonid aquaculture globally. An Enterobacter species, C6-6, isolated from the gut of rainbow trout, Oncorhynchus mykiss (Walbaum), has been identified as a potential probiotic species providing protection against BCWD. This study examined the effects of alginate microencapsulation on the protective efficacy of C6-6 against BCWD in vivo when administered to rainbow trout fry orally or by intraperitoneal (IP) injection. Viable C6-6 bacteria were microencapsulated successfully, and this process (microencapsulation) did not significantly deteriorate its protective properties as compared to the administration of non-microencapsulated C6-6 bacteria. Both oral and IP delivery of C6-6 achieved significantly better protection than control treatments that did not contain C6-6 bacteria. The highest relative percent survival (RPS) resulted from IP delivery (71.4%) and was significantly greater than the highest oral RPS (38.6%). Successful intestinal colonization was not critical to protective effects of C6-6. The study showed that C6-6 administration, with or without encapsulation, was a viable choice for protecting fry from BCWD especially when administered intraperitoneally. © 2014 John Wiley & Sons Ltd.

  15. The Effect on Some Hematologic Blood Parameters of Formaldehyde Bath which was Applıed to Rainbow Trout (Oncorhynchus mykiss

    Directory of Open Access Journals (Sweden)

    Hakan BAYRAM

    2017-06-01

    Full Text Available In this study, it was researched the effects of formaldehyde that used commonly at treatment of fish diseases on hematological parameters of rainbow trout (Oncorhynchus mykiss. According to the result of this study, it was found statisticaly significant (p<0.05 difference among of the hematocrit values that measured at the doses x the time interaction. From the point of view of the hemoglobin amount, the application of doses and the dose x time interaction was very significant (p<0.01 and effect of the application of time was significant (p<0.05. From the point of view of reticulocyte proportion, the application of doses and the application of time interaction was very significant (p<0.01.

  16. Hybridization dynamics between Colorado's native cutthroat trout and introduced rainbow trout.

    Science.gov (United States)

    Metcalf, Jessica L; Siegle, Matthew R; Martin, Andrew P

    2008-01-01

    Newly formed hybrid populations provide an opportunity to examine the initial consequences of secondary contact between species and identify genetic patterns that may be important early in the evolution of hybrid inviability. Widespread introductions of rainbow trout (Oncorhynchus mykiss) into watersheds with native cutthroat trout (Oncorhynchus clarkii) have resulted in hybridization. These introductions have contributed to the decline of native cutthroat trout populations. Here, we examine the pattern of hybridization between introduced rainbow trout and 2 populations of cutthroat trout native to Colorado. For this study, we utilized 7 diagnostic, codominant nuclear markers and a diagnostic mitochondrial marker to investigate hybridization in a population of greenback cutthroat trout (Oncorhynchus clarkii stomias) and a population of Colorado River cutthroat trout (Oncorhynchus clarkii pleuriticus). We infer that cutthroat-rainbow trout hybrid swarms have formed in both populations. Although a mixture of hybrid genotypes was present, not all genotype combinations were detected at expected frequencies. We found evidence that mitochondrial DNA introgression in hybrids is asymmetric and more likely from rainbow trout than from cutthroat trout. A difference in spawning time of the 2 species or differences in the fitness between the reciprocal crosses may explain the asymmetry. Additionally, the presence of intraspecific cytonuclear associations found in both populations is concordant with current hypotheses regarding coevolution of mitochondrial and nuclear genomes.

  17. Identification of suppressor of cytokine signalling (SOCS) 6, 7, 9 and CISH in rainbow trout Oncorhynchus mykiss and analysis of their expression in relation to other known trout SOCS.

    Science.gov (United States)

    Wang, Tiehui; Gao, Qian; Nie, Pin; Secombes, Christopher J

    2010-10-01

    Four new members of the SOCS family of molecules in rainbow trout (Oncorhynchus mykiss), CISH and SOCS6, 7 and 9, are described for the first time in this species. The genes had a wide tissue distribution in trout, and were detected in gills, skin, muscle, liver, spleen, head kidney, intestine and brain, with brain having the highest expression levels. Stimulation of a rainbow trout leucocyte cell line, RTS-11, (mononuclear/macrophage-like cells) with LPS or Poly I:C had no effect on the expression of these genes, although in both cases the previously identified SOCS1-3 genes were up-regulated. Similarly, stimulation of RTS-11 or RTG-2 (fibroblasts) cells with the trout recombinant cytokines IFN-gamma or IL-1beta had no effect on CISH or SOCS6, 7 and 9 expression. However, PMA stimulation did impact on SOCS6 and SOCS9 expression, and LPS stimulation of primary cultures or bacterial infection (Yersinia ruckeri) increased significantly CISH expression (as well as SOCS1 and SOCS2 or SOCS3 respectively). It is apparent that the type II SOCS genes (CISH, SOCS1-3) are particularly relevant to immune regulation in fish, although the intriguing expansion of the SOCS4/5 subgroup in fish requires further investigation as to their role and functional divergence. Copyright 2010 Elsevier Ltd. All rights reserved.

  18. Measurement of total Zn and Zn isotope ratios by quadrupole ICP-MS for evaluation of Zn uptake in gills of brown trout (Salmo trutta) and rainbow trout (Oncorhynchus mykiss)

    Science.gov (United States)

    Wolf, R.E.; Todd, A.S.; Brinkman, S.; Lamothe, P.J.; Smith, K.S.; Ranville, J.F.

    2009-01-01

    This study evaluates the potential use of stable zinc isotopes in toxicity studies measuring zinc uptake by the gills of brown trout (Salmo trutta) and rainbow trout (Oncorhynchus mykiss). The use of stable isotopes in such studies has several advantages over the use of radioisotopes, including cost, ease of handling, elimination of permit requirements, and waste disposal. A pilot study using brown trout was performed to evaluate sample preparation methods and the ability of a quadrupole inductively coupled plasma mass spectrometer (ICP-MS) system to successfully measure changes in the 67Zn/66Zn ratios for planned exposure levels and duration. After completion of the pilot study, a full-scale zinc exposure study using rainbow trout was performed. The results of these studies indicate that there are several factors that affect the precision of the measured 67Zn/66Zn ratios in the sample digests, including variations in sample size, endogenous zinc levels, and zinc uptake rates by individual fish. However, since these factors were incorporated in the calculation of the total zinc accumulated by the gills during the exposures, the data obtained were adequate for their intended use in calculating zinc binding and evaluating the influences of differences in water quality parameters.

  19. Impact of carbon dioxide level, water velocity, and feeding regimen on growth and fillet attributes of cultured rainbow trout (Oncorhynchus mykiss)

    Science.gov (United States)

    Mazik, Patricia M.; Mazik, P.M.; Kenney, P.B.; Silverstein, J.T

    2016-01-01

    Production and management variables such as carbon dioxide (CO2) level, water velocity, and feeding frequency influence the growth and fillet attributes of rainbow trout (Oncorhynchus mykiss), as well as cost of production. More information is needed to determine the contributions of these variables to growth and fillet attributes to find the right balance between input costs and fish performance. Two studies, of 84 and 90 days duration, were conducted to determine the effects of CO2 level, water velocity, and feed frequency on rainbow trout growth, fillet yield, and fillet quality. In the first study, two CO2levels (30 and 49 mg/L) and two velocity levels (0.5 and 2.0 body lengths/s) were tested. In the second study two CO2 levels (30 and 49 mg/L) and two feeding regimens (fed once daily to satiation or three times daily to satiation) were tested. In the first study, after 84 days, fillet weight from high CO2 tanks was 13.5% lower than the fillet weights of fish from low CO2 tanks. Percent fat of fillets was higher in low CO2 fish (P = 0.05) after 84 days and, fish from the low CO2 treatment were larger (P < 0.01). Both studies had similar results in regards to fat content and weight of fillets in response to elevated CO2levels. Velocity had little affect on either whole wet weight or fillet attributes of rainbow trout in this study. Muscle tissue contained more (P < 0.01) fat when fish were fed three times daily (7.3%; day 90) compared to once daily (5.4%; day 90). Also, fish were larger (P < 0.05) when fed 3 times per day (1079 g; day 90) in comparison to only one daily feeding (792 g; day 90). Fish in high feed/high CO2 tanks were larger and had more fillet fat than fish from low feed/low CO2 tanks. To maximize rainbow trout growth at aquaculture facilities, management strategies should attempt to keep CO2 levels below 30 mg/L when cost efficient. However, feeding 2–3 times daily should reduce production losses if CO2 cannot be minimized. The

  20. Morphology, sex steroid level and gene expression analysis in gonadal sex reversal of triploid female (XXX) rainbow trout (Oncorhynchus mykiss).

    Science.gov (United States)

    Xu, Gefeng; Huang, Tianqing; Jin, Xian; Cui, Cunhe; Li, Depeng; Sun, Cong; Han, Ying; Mu, Zhenbo

    2016-02-01

    In non-mammalian vertebrates, estrogens and expressions of cyp19a1 and foxl2 play critical roles in maintaining ovary differentiation and development, while dmrt1 and sox9 are male-specific genes in testicular differentiation and are highly conserved. In order to deeply understand the morphological change, sex steroids level and molecular mechanism of triploid female gonadal reversal in rainbow trout, we studied the ovary morphology, tendency of estradiol-17β (E2) and testosterone (T) levels and the relative expressions of dmrt1, cyp19a1, sox9 and foxl2 in juvenile and adult fish. Our results demonstrated that the development of triploid female gonads in rainbow trout went through arrested development, oocytes dedifferentiation, ovary reconstruction and sex reversal finally. During early gonadal development (154-334 days post-fertilization), the expressions of foxl2 and cyp19a1 increased linearly, while expressions of dmrt1 and sox9 were extremely suppressed, and E2 level was higher, while T level was lower. During the mid-to-late period of triploid female gonadal development (574-964 days post-fertilization), the expressions of dmrt1 and sox9 remained high and were very close to the quantity of diploid male genes, and T levels were even reaching diploid male plasma concentrations, while expressions of cyp19a1 and foxl2 were decreased, leading to decrease in E2 level. We realized that the development model of rainbow trout triploid female gonads was extremely rare, and the regulatory mechanism was very special. Genes involved in gonadal development and endogenous estrogens are pivotal factors in fish natural sex reversal.

  1. Hazelnut meal in diets for seawater farmed rainbow trout (Oncorhynchus mykiss: effects on growth performance and body composition

    Directory of Open Access Journals (Sweden)

    Soner Bilen

    2010-01-01

    Full Text Available A 77-day feeding trial was designed in order to assess the effect of partial or total replacement of soybean meal by hazelnut meal (HNM on feed intake, growth performance, nutrient utilization and body composition of rainbow trout (initial mean body weight: 80.0±3.5 g in seawater conditions. A control and three experimental diets were formulated in which soybean meal level (25.5% in the control diet was replaced by hazelnut meal at 39.2 (HN 39, 78.4 (HN 78 and 100% (HN 100 to provide 44% crude protein and 20% crude lipid diets. Diets were fed to 125 rainbow trout to apparent satiation by hand twice daily at 09.00 and 16.00 hours under natural photoperiod conditions. At the end of the feeding trial, fish of all groups almost tripled their body weight and no significant difference (P>0.05 was revealed in final weight or specific growth rate between treatments. However, feed conversion ratio (FCR of the HN100 group was significantly higher than other treatments (P<0.05. There was a slightly decreasing trend in protein efficiency ratio (PER and net protein utilization (NPU with increasing level of dietary hazelnut meal, but it was only significant in groups of fish fed HN100. All groups of fish displayed similar carcass and muscle compositions. According to the results of the present study, it can be stated that hazelnut meal can replace soybean meal at up to 200 g kg-1 in grow-out diets of rainbow trout without any detrimental effects on growth performance.

  2. Is the intestinal microbiota in rainbow trout (oncorhynchus mykiss) influenced by diet type and challenge by yersinia ruckeri?

    DEFF Research Database (Denmark)

    Ingerslev, Hans-Christian; Dalsgaard, Inger; Jørgensen, Louise von Gersdorff

    2013-01-01

    colonization of pathogenic bacteria. The question is if the gut microbiota is also important in lower vertebrates such as fish? And does it play a role in connection to pathogenic challenge? To examine these questions rainbow trout fry were fed two different diets of either a marine or vegetable origin...... of vegetable fed fish. Several genera within the order Lactobacillales belonged to the many reads from Firmicutes. In challenged fish with a high load of reads from genus Yersinia there was a significantly lower amount of reads from the order Burkholderiales. Further, these fish further clustered separately...

  3. Reciprocal enhancement of uptake and toxicity of cadmium and calcium in rainbow trout (Oncorhynchus mykiss) liver mitochondria

    International Nuclear Information System (INIS)

    Adiele, Reginald C.; Stevens, Don; Kamunde, Collins

    2010-01-01

    The interactive effects of cadmium (Cd) and calcium (Ca) on energy metabolism in rainbow trout liver mitochondria were studied to test the prediction that Ca would protect against Cd-induced mitochondrial liability. Isolated rainbow trout liver mitochondria were energized with malate and glutamate and exposed to increasing concentrations (5-100 μM) of Cd and Ca singly and in combination at 15 o C. Accumulation of Cd and Ca in the mitochondria and mitochondrial respiration (oxygen consumption) rates were measured. Additionally, un-energized mitochondria were incubated with low doses (1 μM) of Cd and Ca singly and in combination, with time-course measurements of cation accumulation/binding and oxygen consumption rates. In energized actively phosphorylating mitochondria, the uptake rates of both Cd and Ca were dose-dependent and enhanced when administered concurrently. Upon low-dose incubation, Cd accumulation was rapid and peaked in 5 min, while no appreciable uptake of Ca occurred. Functionally, the resting (state 4, ADP-limited) respiration rate was not affected in the dose-response exposure, but it decreased remarkably on low-dose incubation. Adenosine diphosphate (ADP)-stimulated respiration (state 3) rate was impaired dose-dependently with maximal inhibitions (at the highest dose, 100 μM) of 32, 64 and 73% for Ca, Cd, and combined exposures, respectively. The combined effects of Ca and Cd suggested synergistic (more than additive) action and partial additivity of effects at low and higher doses of the two cations, respectively. Moreover, on a molar basis, Cd was twice as toxic as Ca to rainbow trout liver mitochondria and when combined, approximately 90% of the effects were attributable to Cd. The coupling efficiency, as measured by respiratory control ratio (RCR) and phosphorylation efficiency, measured as ADP/O ratio, both decreased as the exposure dosage and duration increased. In addition, Cd and Ca exposure decreased mitochondrial proton leak (state 4

  4. Renal Cu and Na excretion and hepatic Cu metabolism in both Cu acclimated and non acclimated rainbow trout (Oncorhynchus mykiss)

    DEFF Research Database (Denmark)

    Grosell, M.; Hogstrand, C.; Wood, C.M.

    1998-01-01

    protein depending on whether the Cu is derived from recent branchial uptake or is already present in the plasma prior to Cu-64 exposure. The plasma Cu pool derived from recent branchial uptake and the Cu pool present in the plasma prior to Cu-64 exposure is accessible to renal excretion to different...... Na+ efflux decreased by 40%, which was largely due to increased tubular Na+ reabsorption. Renal compensation for the impaired branchial Na+ uptake, seen during Cu exposure, thus seems to be involved in Cu acclimation in rainbow trout. (C) 1998 Elsevier Science B.V....

  5. Radiological examination of the spinal column in farmed rainbow trout Oncorhynchus mykiss (Walbaum): experiments with Flavobacterium psychrophilum and oxytetracycline

    DEFF Research Database (Denmark)

    Madsen, Lone; Arnbjerg, J.; Dalsgaard, Inger

    2001-01-01

    Flavobacterium psychrophilum and oxytetracycline have both been associated with spinal deformities in salmonids. Experiments were carried out to investigate whether infection with F, psychrophilum or medication with oxytetracycline (OTC) at the fry stage would result in an increased occurrence...... of infected fish. OTC treatments of up to 200 mg of OTC(kgfish)(-1) day(-1) for 10 days and repeated three times did not result in increased spinal deformities relative to untreated control groups; therefore, medication of rainbow trout with oxytetracycline did not cause deformities of the spinal column under...

  6. Effect of hydrogen peroxide and/or Flavobacterium psychrophilum on the gills of rainbow trout, Oncorhynchus mykiss (Walbaum)

    DEFF Research Database (Denmark)

    Henriksen, Maya Maria Mihályi; Kania, P. W.; Buchmann, K.

    2015-01-01

    The immune response and morphological changes in the gills of rainbow trout fry after immersion in hydrogen peroxide (H2O2), Flavobacterium psychrophilum or combined exposure were examined. The gills were sampled 4, 48, 125 and 192 h after exposure, and the regulation of expression of the following...... with gene expression. Although pretreatment with H2O2 before immersion in F. psychrophilum did not significantly alter the amount of bacteria found in the gill, the immune response was influenced: exposure to F. psychrophilum resulted in a negative correlation with expression of IL‐17c1, MHC I and MHC II...

  7. Comparison of endogenous loss and maintenance need for minerals in rainbow trout (Oncorhynchus mykiss) fed fishmeal or plant ingredient-based diets

    NARCIS (Netherlands)

    Antony Jesu Prabhu, P.; Kaushik, S.J.; Mariojouls, C.; Surget, A.; Fontagné-Dicharry, S.; Schrama, J.W.; Geurden, I.

    2015-01-01

    Mineral needs as affected by changes in dietary protein and oil sources were studied in rainbow trout. Duplicate groups (n = 30 fish per replicate) of rainbow trout (initial BW: 37 g) were fed either a fish meal/fish oil-based (M) or a complete plant ingredient (V)-based diet at four graded ration

  8. 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...

  9. Simultaneous demonstration of infectious pancreatic necrosis virus (IPNV) and Flavobacterium psychrophilum in paraffin-embedded specimens of rainbow trout Oncorhynchus mykiss fry by use of paired immunohistochemistry

    DEFF Research Database (Denmark)

    Evensen, Ø.; Lorenzen, Ellen

    1997-01-01

    The Gram-negative bacterium Flavobacterium psychrophilum, which is the causative agent of rainbow trout fry syndrome (RTFS), and infectious pancreatic necrosis virus (IPNV), the causative agent of infectious pancreatic necrosis (IPN), are both highly pathogenic for rainbow trout fry. Several...

  10. Effect of storage on residue levels of enrofloxacin in muscle of rainbow trout (Oncorhynchus mykiss and common carp (Cyprinus carpio

    Directory of Open Access Journals (Sweden)

    Ralica Kyuchukova

    2016-03-01

    Full Text Available Since fluoroquinolones are one of the most commonly used antibacterial drugs in aquaculture, there is a risk of their residues to be found in the treated fish. The objective of this study was to examine t he changes in enrofloxacin and ciprofloxacin levelsduring storage of rainbow trout and common carp muscle at -18 °C. The trout and carp were treated orally with a single dose of 10 mg/kg of enrofloxacin. Tissue samples were collected 24 h after the treatment and stored at -18 °C for 270 days either as a whole fish or as precut muscle samples. Results for trout revealed that in the precut samples enrofloxacin concentration decreased significantly only after 9 months of storage, whereas a significant decline in the ciprofloxacin level was observed much earlier (after 3 months. After 9 months of storage, the trout stored without being sliced and eviscerated showed significantly higher levels of both quinolones as compared to the precut muscle samples. The enrofloxacin levels in the carp musculature decreased considerably after 3 months of storage and stayed almost unchanged up to the end of the study, whereas the ciprofloxacin concentration continued to drop even after this period and after 270 days constituted 1/6 of the initial values.

  11. Specificity of DNA vaccines against the U and M genogroups of infectious hematopoietic necrosis virus (IHNV) in rainbow trout (Oncorhynchus mykiss)

    Science.gov (United States)

    Penaranda, M.M.D.; LaPatra, S.E.; Kurath, G.

    2011-01-01

    Infectious hematopoietic necrosis virus (IHNV) is a fish rhabdovirus that causes significant mortality in salmonid species. In North America IHNV has three major genogroups designated U, M, and L. Host-specificity of the M and U genogroups of IHNV has been established both in the field and in experimental challenges, with M isolates being more prevalent and more virulent in rainbow trout (Oncorhynchus mykiss), and U isolates being more prevalent and highly virulent in sockeye salmon (Oncorhynchus nerka). In this study, efficacy of DNA vaccines containing either M (pM) or U (pU) virus glycoprotein genes was investigated during intra- and cross-genogroup challenges in rainbow trout. In virus challenges at 7 days post-vaccination (early antiviral response), both pM and pU were highly protective against either M or U IHNV. In challenges at 28 days post-vaccination (specific antiviral response), both pM and pU were protective against M IHNV but the homologous pM vaccine was significantly more protective than pU in one of two experiments. At this stage both pM and pU induced comparably high protection against U IHNV challenge. Correlates of protection were also investigated by assessing the expression of the interferon-stimulated gene Mx-1 and the production of neutralizing antibodies (NAbs) following pM or pU DNA vaccination. Mx-1 gene expression, measured at 4 and 7 days post-vaccination as an indicator of the host innate immune response, was found to be significantly higher after pM than pU vaccination in some cases. Neutralizing antibody was produced in response to the two vaccines, but antibody titers did not show consistent correlation with protection. The results show that the rainbow trout innate and adaptive immune responses have some ability to distinguish between the U and M genogroup IHNV, but overall the pM and pU vaccines were protective against both homologous and cross-genogroup challenges.

  12. Glucose metabolism ontogenesis in rainbow trout (Oncorhynchus mykiss) in the light of the recently sequenced genome: new tools for intermediary metabolism programming.

    Science.gov (United States)

    Marandel, Lucie; Véron, Vincent; Surget, Anne; Plagnes-Juan, Élisabeth; Panserat, Stéphane

    2016-03-01

    The rainbow trout (Oncorhynchus mykiss), a carnivorous fish species, displays a 'glucose-intolerant' phenotype when fed a high-carbohydrate diet. The importance of carbohydrate metabolism during embryogenesis and the timing of establishing this later phenotype are currently unclear. In addition, the mechanisms underlying the poor ability of carnivorous fish to use dietary carbohydrates as a major energy substrate are not well understood. It has recently been shown in trout that duplicated genes involved in glucose metabolism may participate in establishing the glucose-intolerant phenotype. The aim of this study was therefore to provide new understanding of glucose metabolism during ontogenesis and nutritional transition, taking into consideration the complexity of the trout genome. Trout were sampled at several stages of development from fertilization to hatching, and alevins were then fed a non-carbohydrate or a high-carbohydrate diet during first feeding. mRNA levels of all glucose metabolism-related genes increased in embryos during the setting up of the primitive liver. After the first meal, genes rapidly displayed expression patterns equivalent to those observed in the livers of juveniles. g6pcb2.a (a glucose 6-phosphatase-encoding gene) was up-regulated in alevins fed a high-carbohydrate diet, mimicking the expression pattern of gck genes. The g6pcb2.a gene may contribute to the non-inhibition of the last step of gluconeogenesis and thus to establishing the glucose-intolerant phenotype in trout fed a high-carbohydrate diet as early as first feeding. This information is crucial for nutritional programming investigations as it suggests that first feeding would be too late to programme glucose metabolism in the long term. © 2016. Published by The Company of Biologists Ltd.

  13. Depletion of isoeugenol residues from the fillet tissue of AQUI-S™ exposed rainbow trout (Oncorhynchus mykiss)

    Science.gov (United States)

    Meinertz, Jeffery R.; Schreier, Theresa M.

    2009-01-01

    There is a critical need in U.S. public aquaculture and fishery management for an approved sedative that allows for the immediate release of fish after sedation. AQUI-STM is a fish anesthetic/sedative approved for use in several countries and until recently was being developed in the U.S. as a sedative for immediate release of fish after sedation. The U.S. National Toxicology Program reported that isoeugenol (the active ingredient in AQUI-STM) exposed male mice showed clear evidence of carcinogenicity, therefore efforts within the U.S. Department of Interior to develop AQUI-STM as a sedative that allows for immediate release ceased. Despite the ruling, AQUI-STM still has the potential to be approved as an anesthetic with a short withdrawal time. Among the data required to gain approval for use in the U.S. are data describing the composition and depletion of all AQUI-STM residues from fish fillet tissue. A total residue depletion study for AQUI-STM was conducted by exposing market-sized rainbow trout, Oncorhynchus mykiss (mean weight, 502.7 ± 54 g; s.d.) to 8.9 mg/L of 14C-[URL]-isoeugenol for 60 min in 17 °C water. The 14C-[URL]-isoeugenol was mixed with a surfactant resulting in a mixture that mimicked AQUI-STM. Groups of fish (n = 6) were sampled immediately after the exposure (0-h sample group) and at 0.5, 1, 2, and 4 h thereafter. Total isoeugenol-equivalent residue concentrations in the fillet tissue were determined by oxidizing triplicate subsamples of homogenized skin-on fillet tissue from each fish to 14CO2 and enumerating the radioactivity by static liquid scintillation counting. Isoeugenol concentrations in fillet tissue were determined by extracting homogenized fillet tissue with solvents and determining the isoeugenol concentrations in the extracts with high performance liquid chromatography techniques. The mean total isoeugenol-equivalent residue concentrations in the 0, 0.5, 1, 2, and 4-h sample groups were 55.4, 32.0, 19.8, 11

  14. Effects of cooking methods on electrophoretic patterns of rainbow trout

    Directory of Open Access Journals (Sweden)

    Yasemen Yanar

    2011-07-01

    Full Text Available The aim of this study was to determine the effects of different cooking methods on the electrophoretic patterns of rainbow trout (Oncorhynchus mykiss fillets using sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE. Raw rainbow trout were deep-fried, microwaved, grilled, and baked and then monitored for changes in the electrophoretic pattern. All cooking methods resulted in significant moisture loss when compared to the raw sample (P

  15. Effects of the aromatase inhibitor Letrozole on serum immunoglobulin and lysozyme levels in immunized rainbow trout (Oncorhynchus mykiss Walbaum females

    Directory of Open Access Journals (Sweden)

    Paria Akbary

    2013-12-01

    Full Text Available Letrozole is a synthetic aromatase inhibitor and interfere in the committed step in the synthesis of endogenous estrogens from androgens. Also estrogens regulate the immune system in teleost. Changes of 17- β- esrtradiol (E2, serum immunoglobulin and lysozyme levels were measured using a method based on the ability of lysozyme to lyse the bacterium Micrococcus lysodeikticus, enzyme-linked immunosorbent assay (ELISA and ELISA respectively. Twelve broodstocks were injected weekly with 2.5 mg kg-1 letrozole (an endocrine disrupter component two months before spawning season and vaccinated intraperitoneally (i.p with a bacterin (inactivated L. garviae one month before spawning. Twelve broodstocks for vaccination and twelve female rainbow trout as control group were also immiunised (i.p with the bacterin and injected (i.p with PBS, respectively. In the group received 2.5 mg AI kg-1 per week, serum E2 levels were significantly lower than that of other groups. Total immunoglobulin level and lysozyme activity were significantly higher in the parents received 2.5 mg kg-1 per week and were immunized with 10-9 cells ml-1 Lactococcus garvieae  compared to the group which immunized with L. garvieae and the control (non- immunized. The present study, suggests that aromatase inhibitors such as letrozole may be a potential tool to regulate the synthesis of E2, is involved in the hormone- immune system interaction in rainbow trout.

  16. Three-dimensional imaging analysis of Yersinia ruckeri infected rainbow trout (Oncorhynchus mykiss) gills by optical projection tomography

    DEFF Research Database (Denmark)

    Otani, Maki; Raida, Martin Kristian

    Optical projection tomography (OPT) is a new tool for three-dimensional (3D) imaging of small tissues or embryos, based on multi-angle recording of internal fluorescent signals using intact whole mount tissue or fish. To understand the route of infection, gills of Y. ruckeri infected rainbow trout...... were labeled with fluorescent antibody and visualized in 3D by the OPT scanner. Rainbow trout were infected with Y. ruckeri O1 biotype 1 (1 x 109 cells/ml) for 1 hour at 18 °C, and then transferred to clean water. Three fish were sampled at 12 different time points and fixed in 4% PFA. The gills were...... incubated whole with rabbit anti-Y. ruckeri polyclonal antibody and Alexa Fluor®594 conjugated goat anti-rabbit IgG. After embedding in 1% low melting point agarose, specimens were dehydrated in 100% methanol and cleared in BABB (benzyl alcohol: benzyl benzoate) for OPT scanning. 3D imaging results showed...

  17. Evidence for the Presence of Glucosensor Mechanisms Not Dependent on Glucokinase in Hypothalamus and Hindbrain of Rainbow Trout (Oncorhynchus mykiss.

    Directory of Open Access Journals (Sweden)

    Cristina Otero-Rodiño

    Full Text Available We hypothesize that glucosensor mechanisms other than that mediated by glucokinase (GK operate in hypothalamus and hindbrain of the carnivorous fish species rainbow trout and stress affected them. Therefore, we evaluated in these areas changes in parameters which could be related to putative glucosensor mechanisms based on liver X receptor (LXR, mitochondrial activity, sweet taste receptor, and sodium/glucose co-transporter 1 (SGLT-1 6 h after intraperitoneal injection of 5 mL x Kg(-1 of saline solution alone (normoglycaemic treatment or containing insulin (hypoglycaemic treatment, 4 mg bovine insulin x Kg(-1 body mass, or D-glucose (hyperglycaemic treatment, 500 mg x Kg(-1 body mass. Half of tanks were kept at a 10 Kg fish mass x m(-3 and denoted as fish under normal stocking density (NSD whereas the remaining tanks were kept at a stressful high stocking density (70 kg fish mass x m(-3 denoted as HSD. The results obtained in non-stressed rainbow trout provide evidence, for the first time in fish, that manipulation of glucose levels induce changes in parameters which could be related to putative glucosensor systems based on LXR, mitochondrial activity and sweet taste receptor in hypothalamus, and a system based on SGLT-1 in hindbrain. Stress altered the response of parameters related to these systems to changes in glycaemia.

  18. Interactive effects of dietary palm oil concentration and water temperature on lipid digestibility in rainbow trout, Oncorhynchus mykiss.

    Science.gov (United States)

    Ng, Wing-Keong; Campbell, Patrick J; Dick, James R; Bell, J Gordon

    2003-10-01

    An experiment was conducted to evaluate the interactive effects of dietary crude palm oil (CPO) concentration and water temperature on lipid and FA digestibility in rainbow trout. Four isolipidic diets with 0, 5, 10, or 20% (w/w) CPO, at the expense of fish oil, were formulated and fed to groups of trout maintained at water temperatures of 7, 10, or 15 degrees C. The apparent digestibility (AD) of the FA, measured using yttrium oxide as an inert marker, decreased with increasing chain length and increased with increasing unsaturation within each temperature regimen irrespective of CPO level fed to the fish. PUFA of the n-3 series were preferentially absorbed compared to n-6 PUFA in all diet and temperature treatments. Except for a few minor FA, a significant (P digestibility was found. Increasing dietary levels of CPO lead to significant reductions in the AD of saturates and, to a lesser extent, also of the other FA. Lowering water temperature reduced total saturated FA digestibility in trout regardless of CPO level. Based on the lipid class composition of trout feces, this reduction in AD of saturates was due in part to the increasing resistance of dietary TAG to digestion. Increasing CPO level and decreasing water temperature significantly increased TAG content in trout fecal lipids, with saturates constituting more than 60% of the FA composition. Total monoene and PUFA digestibilities were not significantly affected by water temperature in fish fed up to 10% CPO in their diet. The potential impact of reduced lipid and FA digestibility in cold-water fish fed diets supplemented with high levels of CPO on fish growth performance requires further research.

  19. Effects of dietary supplementation with krill meal on pigmentation and quality of flesh of rainbow trout (Oncorhynchus mykiss

    Directory of Open Access Journals (Sweden)

    Federico Sirri

    2011-04-01

    Full Text Available Effects of administration of krill meal and synthetic astaxanthin during the finisher phase of the fattening cycle of rainbow trout on flesh pigmentation and quality traits were studied. The inclusion of krill meal increased the body weight and size and decreased the peri-visceral fat and visceral weight indices. The astaxanthin diet produced the highest accumulation of total carotenoids in the fillet compared to the krill meal diet: the difference was significant after 15 days of feeding (2.50 vs 2.10 mg/kg till the end of the trial (5.00 vs 4.80 mg/kg. The same pattern was observed for astaxanthin concentration with the highest values in the fillets of fish fed the astaxanthin diet. Fillet lightness (L* was not affected by trout diets whereas redness (a* and yellowness (b* were significantly higher in fish fed the astaxanthin diet until day 30 of the trial. Hue was not affected by feeding, whereas chroma was significantly higher in the fish fed astaxanthin throughout the trial except on day 45 of sampling. Trout fed the krill meal diet had a paler pink-red colour on the SalmoFan scale than those receiving the astaxanthin diet. No significant differences emerged in proximate composition and cholesterol content of trout in the two groups. The fatty acid profile of the fillets reflected the fatty acids of the diets administered to the trout: eicosapentaenoic, docosahexaenoic and docosapentaenoic acids and total n-3 polyunsaturated fatty acids were significantly higher in the fish fed the krill meal.

  20. Ultrastructural effects of pharmaceuticals (carbamazepine, clofibric acid, metoprolol, diclofenac) in rainbow trout (Oncorhynchus mykiss) and common carp (Cyprinus carpio).

    Science.gov (United States)

    Triebskorn, R; Casper, H; Scheil, V; Schwaiger, J

    2007-02-01

    In order to assess potential effects of human pharmaceuticals in aquatic wildlife, laboratory experiments were conducted with carbamazepine, clofibric acid, metoprolol, and diclofenac using fish as test organisms. For each substance, at least one environmentally relevant concentration was tested. In liver, kidney, and gills of trout and carp exposed to carbamazepine, clofibric acid, and metoprolol, ultrastructural effects were qualitatively described and semi-quantitatively assessed. The obtained assessment values were compared with previously published data for diclofenac-induced effects in rainbow trout tissues. Quantitative analyses of protein accumulated in kidneys of diclofenac-exposed trout corroborated previously published data which indicated that diclofenac induced a severe glomerulonephritis resulting in a hyaline droplet degeneration of proximal kidney tubules. The investigations provided information on the general health status of the pharmaceutical-exposed fish, and allowed a differential diagnosis of harmful effects caused by these human pharmaceuticals in non-target species. For the different cytological effects observed, lowest observed effect concentration (LOECs) for at least three of the test substances (diclofenac, carbamazepine, metoprolol) were in the range of environmentally relevant concentrations (1 microg/L).

  1. [Effect of a supplemental Aspergillus niger phytase on the utilization of plant phosphorus by rainbow trout (Oncorhynchus mykiss)].

    Science.gov (United States)

    Rodehutscord, M; Becker, A; Pfeffer, E

    1995-01-01

    Effects of a supplemental Aspergillus niger-phytase on digestibility and utilization of dietary phosphorus (P) were studied in three experiments with rainbow trout. P concentration in the diets was 4.8 and 5.8 g/kg DM, respectively. The P contained in the diet originated solely from plants, mainly soy-products. Digestibility of P was studied using the stripping method and hydrochloride insoluble ash as marker. Utilization was studied in growth trials by use of the comparative body analysis. At a water temperature of 15 degrees C, both digestibility and utilization of P were increased from 25 to 57% and from 17 to 49%, respectively when 1000 U/kg phytase were supplemented. Feed consumption and gain of trout were significantly increased. At a water temperature of 10 degrees C, utilization of P was also increased from 6 to 25%. However, feed consumption and gain of trout were very low at this water temperature and not influenced by the supplemental phytase.

  2. Involvement of cortisol and sirtuin1 during the response to stress of hypothalamic circadian system and food intake-related peptides in rainbow trout, Oncorhynchus mykiss.

    Science.gov (United States)

    Naderi, Fatemeh; Hernández-Pérez, Juan; Chivite, Mauro; Soengas, José L; Míguez, Jesús M; López-Patiño, Marcos A

    2018-05-08

    Stress is conditioning animal welfare by negatively affecting a wide range of physiological and behavioral functions. This may be applied to circadian physiology and food intake. Cortisol, the stress-related hormone, may mediate such effect of stress, but other indirect mediators might be considered, such as sirtuin1. Then, either the independent modulatory effect or the existence of any interaction between mediators may be responsible. The circadian system is the main modulator of several integrative mechanisms at both central and peripheral levels that are rhythmically presented, thus influencing different processes such as food intake. In this way, food intake is controlled by the circadian system, as demonstrated by the persistence of such rhythms of food intake in the absence of environmental external cues. Our study aimed to evaluate the daily profile of hypothalamic mRNA abundance of circadian clock genes (clock1a, bmal1, per1 and rev-erbβ-like), and food intake regulators (crf, pomc-a1, cart, and npy) in rainbow trout (Oncorhynchus mykiss), the impact of stress on such rhythms, and the involvement of cortisol and sirtuin1 as mediators. Four cohorts of trout were subjected to 1) normal stocking density (control group), 2) high stocking density for 72 hours (stress group), 3) normal stocking density and implanted with mifepristone, a glucocorticoid receptors antagonist, and 4) mifepristone administered and stressed for 72 hours. Fish from each group were sampled every 4-h along the 24-h LD cycle, and cortisol, glucose and lactate plasma levels were evaluated. Hypothalamic mRNA abundance of clock genes, food intake regulators, glucocorticoid receptors and sirtuin1 were qPCR assayed. Our results reveal the impact of stress on most of the genes assayed, but different mechanisms appear to be involved. The rhythm of clock genes displayed decreased amplitude and averaged levels in stressed trout, with no changes of the acrophase being observed. This effect was

  3. Plasma nesfatin-1 is not affected by long-term food restriction and does not predict rematuration among iteroparous female rainbow trout (Oncorhynchus mykiss).

    Science.gov (United States)

    Caldwell, Lucius K; Pierce, Andrew L; Riley, Larry G; Duncan, Christine A; Nagler, James J

    2014-01-01

    The metabolic peptide hormone nesfatin-1 has been linked to the reproductive axis in fishes. The purpose of this study was to determine how energy availability after spawning affects plasma levels of nesfatin-1, the metabolic peptide hormone ghrelin, and sex steroid hormones in rematuring female rainbow trout (Oncorhynchus mykiss). To limit reproductive maturation, a group of female trout was food-restricted after spawning and compared with a control group that was fed a standard broodstock ration. The experiment was conducted twice, once using two-year-old trout (second-time spawners) and once using three-year-old trout (third-time spawners). During monthly sampling, blood was collected from all fish, and a subset of fish from each treatment was sacrificed for pituitaries. Pituitary follicle-stimulating hormone-beta (fsh-β) mRNA expression was analyzed with q-RT-PCR; plasma hormone levels were quantified by radioimmunoassay (17β-estradiol and ghrelin) and enzyme-linked immunosorbent assay (11-keto-testosterone and nesfatin-1). Although plasma nesfatin-1 levels increased significantly in the months immediately after spawning within both feeding treatments, plasma nesfatin-1 did not differ significantly between the two treatments at any point. Similarly, plasma ghrelin levels did not differ significantly between the two treatments at any point. Food restriction arrested ovarian development by 15-20 weeks after spawning, shown by significantly lower plasma E2 levels among restricted-ration fish. Pituitary fsh-β mRNA levels were higher among control-ration fish than restricted-ration fish starting at 20 weeks, but did not differ significantly between treatment groups until 30 weeks after spawning. Within both treatment groups, plasma 11-KT was elevated immediately after spawning and rapidly decreased to and persisted at low levels; starting between 20 and 25 weeks after spawning, plasma 11-KT was higher among control-ration fish than restricted-ration fish. The

  4. Growth, morphology, and developmental instability of rainbow trout, Yellowstone cutthroat trout, and four hybrid generations

    Science.gov (United States)

    Ostberg, C.O.; Duda, J.J.; Graham, J.H.; Zhang, S.; Haywood, K. P.; Miller, B.; Lerud, T.L.

    2011-01-01

    Hybridization of cutthroat trout Oncorhynchus clarkii with nonindigenous rainbow trout O. mykiss contributes to the decline of cutthroat trout subspecies throughout their native range. Introgression by rainbow trout can swamp the gene pools of cutthroat trout populations, especially if there is little selection against hybrids. We used rainbow trout, Yellowstone cutthroat trout O. clarkii bouvieri, and rainbow trout × Yellowstone cutthroat trout F1 hybrids as parents to construct seven different line crosses: F1 hybrids (both reciprocal crosses), F2 hybrids, first-generation backcrosses (both rainbow trout and Yellowstone cutthroat trout), and both parental taxa. We compared growth, morphology, and developmental instability among these seven crosses reared at two different temperatures. Growth was related to the proportion of rainbow trout genome present within the crosses. Meristic traits were influenced by maternal, additive, dominant, overdominant, and (probably) epistatic genetic effects. Developmental stability, however, was not disturbed in F1 hybrids, F2 hybrids, or backcrosses. Backcrosses were morphologically similar to their recurrent parent. The lack of developmental instability in hybrids suggests that there are few genetic incompatibilities preventing introgression. Our findings suggest that hybrids are not equal: that is, growth, development, character traits, and morphology differ depending on the genomic contribution from each parental species as well as the hybrid generation.

  5. Oxidative stress biomarkers in different tissues of rainbow trout (Oncorhynchus mykiss exposed to Disinfectant-CIP formulated with peracetic acid and hydrogen peroxide

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    Tkachenko Halyna

    2014-09-01

    Full Text Available The aim of study was to determine the effects of exposure to the product DEZYNFEKTANT-CIP (Eng. - Disinfectant-CIP, which is formulated with peracetic acid and hydrogen peroxide, on oxidative stress biomarkers (lipid peroxidation (LPO levels and the carbonyl content of oxidatively modified proteins and antioxidant defenses (superoxide dismutase (SOD, catalase (CAT, glutathione reductase (GR, glutathione peroxidase (GPx, total antioxidant capacity in muscle, gill, hepatic, and cardiac tissues of rainbow trout, Oncorhynchus mykiss (Walbaum. LPO and carbonyl contents changed with tissue type. Exposure to Disinfectant-CIP led to a significant decrease in LPO in muscle tissues and carbonyl content in muscle and gill tissues. The inhibition of SOD and CAT activity in muscle, hepatic, and cardiac tissues was observed probably because of increased oxidative stress during disinfection; however, hepatic and cardiac GPx activity increased in an attempt to counteract oxidative stress. We suggest that oxidative stress during the oxidation of peracetic acid and hydrogen peroxide could be counteracted by the antioxidant system in trout tissues. Correlative analysis between oxidative stress biomarkers and antioxidant defense confirms the pivotal role of SOD and CAT against CIP-induced oxidative stress

  6. Effects of ozone, ultraviolet and peracetic acid disinfection of a primary-treated municipal effluent on the immune system of rainbow trout (Oncorhynchus mykiss).

    Science.gov (United States)

    Hébert, N; Gagné, F; Cejka, P; Bouchard, B; Hausler, R; Cyr, D G; Blaise, C; Fournier, M

    2008-08-01

    Municipal sewage effluents are complex mixtures that are known to compromise the health condition of aquatic organisms. The aim of this study was to evaluate the impacts of various wastewater disinfection processes on the immune system of juvenile rainbow trout (Oncorhynchus mykiss). The trout were exposed to a primary-treated effluent for 28 days before and after one of each of the following treatments: ultraviolet (UV) radiation, ozonation and peracetic acid. Immune function was characterized in leucocytes from the anterior head kidney by the following three parameters: phagocytosis activity, natural cytotoxic cells (NCC) function and lymphocyte (B and T) proliferation assays. The results show that the fish mass to length ratio was significantly decreased for the primary-treated and all three disinfection processes. Exposure to the primary-treated effluent led to a significant increase in macrophage-related phagocytosis; the addition of a disinfection step was effective in removing this effect. Both unstimulated and mitogen-stimulated T lymphocyte proliferation in fish decreased dramatically in fish exposed to the ozonated effluent compared to fish exposed to either the primary-treated effluent or to aquarium water. Stimulation of T lymphocytes proliferation was observed with the peracetic acid treatment group. In conclusion, the disinfection strategy used can modify the immune system in fish at the level of T lymphocyte proliferation but was effective to remove the effects on phagocytosis activity.

  7. First evidence of the pore-forming properties of a keratin from skin mucus of rainbow trout (Oncorhynchus mykiss, formerly Salmo gairdneri).

    Science.gov (United States)

    Molle, Virginie; Campagna, Sylvie; Bessin, Yannick; Ebran, Nathalie; Saint, Nathalie; Molle, Gérard

    2008-04-01

    The epidermis of fish is covered with a layer of mucus, which contributes to the defence of the species against parasites, bacteria and fungi. We have previously extracted glycoproteins from various mucus samples from fish and have shown that they present pore-forming activities well correlated with strong antibacterial properties [Ebran, Julien, Orange, Saglio, Lemaitre and Molle(2000) Biochim. Biophys. Acta 1467, 271-280]. The present study focuses on the 65 kDa glycoprotein, Tr65, from the rainbow trout (Oncorhynchus mykiss, formerly Salmo gairdneri).Enzymatic digestion of Tr65 yielded a fragment pattern with strong homology with that of trout type II cytokeratin. Sequence analysis of the cDNA clone obtained by PCR confirmed this homology. We thus constructed a plasmid to overproduce the recombinant Tr65. We extracted and purified this recombinant Tr65, using it for multichannel and single-channel experiments in azolectin bilayers. Our results with recombinant Tr65 confirmed the pore-forming properties already shown with native antibacterial Tr65. These findings offer new insights into the function of keratin proteins present in various mucosal surfaces of animals and human beings.

  8. Acute and chronic sensitivity of white sturgeon (Acipenser transmontanus) and rainbow trout (Oncorhynchus mykiss) to cadmium, copper, lead, or zinc in laboratory water-only exposures

    Science.gov (United States)

    Ingersoll, Christopher G.; Contributions by Wang, Ning; Calfee, Robin D.; Beahan, Erinn; Brumbaugh, William G.; Dorman, Rebecca A.; Hardesty, Doug K.; Kunz, James L.; Little, Edward E.; Mebane, Christopher A.; Puglis, Holly J.

    2014-01-01

    White sturgeon (Acipenser transmontanus) are experiencing poor recruitment in the trans boundary reach of the upper Columbia River in eastern Washington State. Limited toxicity data indicated that early life stages of white sturgeon are sensitive to metals. In acute 4-day (d) exposures with larval white sturgeon, previous studies have reported that the 4-day median lethal concentrations (LC50) based on biotic ligand model (BLM) normalization for copper were below the U.S. Environmental Protection Agency national recommended acute water-quality criterion. In previously published chronic 66-d exposures starting with newly fertilized eggs of white sturgeon, 20-percent lethal effect concentrations (LC20s) for copper, cadmium, or zinc generally were within a factor of two of the chronic values of the most sensitive fish species in the databases of the U.S. Environmental Protection Agency water-quality criteria (WQC) for the three metals. However, there were some uncertainties in the chronic exposures previously performed with white sturgeon, including (1) low control survival (37 percent), (2) more control fish tested in each replicate compared to other treatments, (3) limited replication of treatments (n=2), (4) lack of reported growth data (such as dry weight), and (5) wide dilution factors for exposure concentrations (6- to 8-fold dilutions). The U.S. Environmental Protection Agency concluded that additional studies are needed to generate more toxicity data to better define lethal and sublethal toxicity thresholds for metals for white sturgeon. The objective of the study was to further evaluate the acute and chronic toxicity of cadmium, copper, lead, or zinc to early life stages of white sturgeon in water-only exposures. Toxicity tests also were performed with commonly tested rainbow trout (Oncorhynchus mykiss) under similar test conditions to determine the relative sensitivity between white sturgeon and rainbow trout to these metals. Toxicity data generated from

  9. BIOCHEMICAL STATUS OF BLOOD SERUM OF RAINBOW TROUT Oncorhynchus mykiss (Walbaum, 1792 UNDER DIFFERENT KEEPING AND FEEDING CONDITIONS

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    Edhem Hasković

    2013-01-01

    Full Text Available We analyzed the blood serum of the rainbow trout in relation to various physico-chemical properties of water and diet composition. Fish were reared in two ponds that were supplied by water from different sources. The identified differences in the biochemical parameters are caused by different environmental factors in ponds and different feed composition. Low oxygen values caused by different temperatures is a key stress factor of the noted differences. Statistically significant differences are noted for AST (aspartate aminotransferase, ALT (alanine aminotransferase, triglycerides, urea and iron (0.00. Evident were also different mineral concentrations of Ca and P (0.05 as well as glucose and cholesterol (0.05.

  10. Response of lactate metabolism in brain glucosensing areas of rainbow trout (Oncorhynchus mykiss) to changes in glucose levels.

    Science.gov (United States)

    Otero-Rodiño, Cristina; Librán-Pérez, Marta; Velasco, Cristina; Álvarez-Otero, Rosa; López-Patiño, Marcos A; Míguez, Jesús M; Soengas, José L

    2015-12-01

    There is no evidence in fish brain demonstrating the existence of changes in lactate metabolism in response to alterations in glucose levels. We induced in rainbow trout through intraperitoneal (IP) treatments, hypoglycaemic or hyperglycaemic changes to assess the response of parameters involved in lactate metabolism in glucosensing areas like hypothalamus and hindbrain. To distinguish those effects from those induced by peripheral changes in the levels of metabolites or hormones, we also carried out intracerebroventricular (ICV) treatments with 2-deoxy-D-glucose (2-DG, a non-metabolizable glucose analogue thus inducing local glucopenia) or glucose. Finally, we also incubated hypothalamus and hindbrain in vitro in the presence of increased glucose concentrations. The changes in glucose availability were in general correlated to changes in the amount of lactate in both areas. However, when we assessed in these areas the response of parameters related to lactate metabolism, the results obtained were contradictory. The increase in glucose levels did not produce in general the expected changes in those pathways with only a minor increase in their capacity of lactate production. The decrease in glucose levels was, however, more clearly related to a decreased capacity of the pathways involved in the production and use of lactate, and this was especially evident after ICV treatment with 2-DG in both areas. In conclusion, the present results while addressing the existence of changes in lactate metabolism after inducing changes in glucose levels in brain glucosensing areas only partially support the possible existence of an astrocyte-neuron lactate shuttle in hypothalamus and hindbrain of rainbow trout relating glucose availability to lactate production and use.

  11. A lethal effect associated with polymorphism of the NOR-bearing chromosomes in rainbow trout (Oncorhynchus mykiss

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    Fábio Porto-Foresti

    2004-01-01

    Full Text Available Cytogenetic analysis of a rainbow trout stock showed that the nucleolar organizing regions were located subterminally on the long arm of a submetacentric chromosome pair and occurred as a single chromosomal segment (phenotype N1 or as two chromosomal segments separated by a short euchromatic segment (phenotype N2. Cytogenetic analysis also showed that there were N1N1 and N1N2 individuals but no N2N2 individuals. Analysis of the different includedphenotypes incluted that the population was not in Hardy-Weinberg equilibrium (chi² = 19.333; p < 0.01, and that a higher frequency of individuals had the N1N2 phenotype. Experimental crosses involving four males (two N1N1 and two N1N2 and four females (one N1N1 and three N1N2 yielded eight broods. There were no significant differences between the expected and observed frequencies of offspring resulting from crosses involving N1N1 x N1N2 individuals. However, significant differences were seen in crosses involving N1N2 x N1N2 parents because of the a high incidence of N1N2 fishes and the absense of N2N2. The lack of N2N2 individuals in the parental sample and their absence among the offspring of the experimental crosses suggested that this genetic combination may be lethal in rainbow trout. The survival rates of embryonic "eyed egg" and fry stage individuals were not different, indicating that the possible lethal effect may occur during more advanced ontogenetic phases.

  12. Evaluation of the antifungal activity of Zataria multiflora, Geranium herbarium, and Eucalyptus camaldolensis essential oils on Saprolegnia parasitica-infected rainbow trout (Oncorhynchus mykiss) eggs.

    Science.gov (United States)

    Khosravi, Ali Reza; Shokri, Hojjatollah; Sharifrohani, Mostafa; Mousavi, Hosseinali Ebrahimzadeh; Moosavi, Zahra

    2012-07-01

    The purpose of the present study was to evaluate and assess the capability of Zataria multiflora, Geranium herbarium, and Eucalyptus camaldolensis essential oils in treating Saprolegnia parasitica-infected rainbow (Oncorhynchus mykiss) trout eggs. A total of 150 infected eggs were collected and plated on glucose-pepton agar at 24°C for 2 weeks. The antifungal assay of essential oils against S. parasitica was determined by a macrodilution broth technique. The eggs were treated with essential oils at concentrations of 1, 5, 10, 25, 50, and 100 ppm daily with three repetitions until the eyed eggs stage. Of 150 eggs examined, S. parasitica (54.3%), Saprolegnia spp. (45%), and Fusarium solani (0.7%) were isolated. The minimum inhibitory concentrations of Z. multiflora, E. camaldolensis, and G. herbarium essential oils against S. parasitica were 0.9, 2.3, and 4.8 ppm, respectively. Zataria multiflora and E. camaldolensis at concentrations of 25, 50, and 100 ppm, and G. herbarium at concentration of 100 ppm had significant differences in comparison with negative control (pherbarium treated eggs had remained the most number of final eyed eggs after treatment. The highest final larvae rates belonged to malachite green, E. camaldolensis, Z. multiflora, and G. herbarium, respectively. The most hatching rates were recorded with malachite green (22%), and then Z. multiflora (11%), E. camaldolensis (7%), G. herbarium (3%), and negative control (1%). Zataria multiflora and E. camaldolensis were more effective than G. herbarium for the treatment of S. parasitica-infected rainbow trout eggs in aquaculture environment.

  13. Role of glutathione redox cycle and catalase in defense against oxidative stress induced by endosulfan in adrenocortical cells of rainbow trout (Oncorhynchus mykiss)

    International Nuclear Information System (INIS)

    Dorval, J.; Hontela, A.

    2003-01-01

    The role of antioxidants in maintaining the functional integrity of adrenocortical cells during in vitro exposure to endosulfan, an organochlorine pesticide, was investigated in rainbow trout (Oncorhynchus mykiss). Aminotriazole (ATA), an inhibitor of catalase (CAT), L-buthionine sulfoximine (L-BSO), an inhibitor of glutathione (GSH) synthesis, and N-acetyl cysteine (NAC), a glutathione precursor, were used to investigate the role of CAT and GSH redox cycle in protection against the adrenal toxicity of endosulfan, a pesticide that impairs cell viability (LC 50 366 μM) and cortisol secretion (EC 50 19 μM) in a concentration-related manner. Pretreatment with ATA and L-BSO enhanced the toxicity of endosulfan (LC 50 and EC 50 , respectively, 302 and 2.6 μM with ATA, 346 and 3.1 μM with L-BSO), while pretreatment with NAC had no significant effect on cell viability and increased the EC 50 of endosulfan to 51 μM. CAT activity was significantly reduced following exposure to endosulfan when cells were pretreated with ATA. Pretreatment with L-BSO significantly decreased glutathione peroxidase (GPx) activity and reduced glutathione (GSH) levels in a concentration-related manner following exposure to endosulfan, while GSH levels were significantly higher in NAC pretreated cells compared to untreated cells. Finally, pretreatment with ATA and L-BSO increased, while pretreatment with NAC decreased, lipid hydroperoxides (LOOH) levels. CAT, GPx, and GSH were identified as important antioxidants in maintaining the function and integrity of rainbow trout adrenocortical cells and ATA, L-BSO, and NAC were identified as effective modulators of CAT and GSH redox cycle. Moreover, this study suggests that the glutathione redox cycle may be more efficient than catalase in protecting adrenocortical cells against endosulfan-induced oxidative stress

  14. Aquacultured Rainbow Trout (Oncorhynchus mykiss) Possess a Large Core Intestinal Microbiota That Is Resistant to Variation in Diet and Rearing Density

    Science.gov (United States)

    Wong, Sandi; Waldrop, Thomas; Summerfelt, Steven; Davidson, John; Barrows, Frederic; Kenney, P. Brett; Welch, Timothy; Wiens, Gregory D.; Snekvik, Kevin

    2013-01-01

    As global aquaculture fish production continues to expand, an improved understanding of how environmental factors interact in fish health and production is needed. Significant advances have been made toward economical alternatives to costly fishmeal-based diets, such as grain-based formulations, and toward defining the effect of rearing density on fish health and production. Little research, however, has examined the effects of fishmeal- and grain-based diets in combination with alterations in rearing density. Moreover, it is unknown whether interactions between rearing density and diet impact the composition of the fish intestinal microbiota, which might in turn impact fish health and production. We fed aquacultured adult rainbow trout (Oncorhynchus mykiss) fishmeal- or grain-based diets, reared them under high- or low-density conditions for 10 months in a single aquaculture facility, and evaluated individual fish growth, production, fin indices, and intestinal microbiota composition using 16S rRNA gene sequencing. We found that the intestinal microbiotas were dominated by a shared core microbiota consisting of 52 bacterial lineages observed across all individuals, diets, and rearing densities. Variations in diet and rearing density resulted in only minor changes in intestinal microbiota composition despite significant effects of these variables on fish growth, performance, fillet quality, and welfare. Significant interactions between diet and rearing density were observed only in evaluations of fin indices and the relative abundance of the bacterial genus Staphylococcus. These results demonstrate that aquacultured rainbow trout can achieve remarkable consistency in intestinal microbiota composition and suggest the possibility of developing novel aquaculture strategies without overtly altering intestinal microbiota composition. PMID:23770898

  15. Effects of Discontinuous Administration of Dietary Mannan oligosaccharide and β-1,3-glucan on Hematological and Blood Serum Biochemical Parameters of Rainbow trout (Oncorhynchus mykiss

    Directory of Open Access Journals (Sweden)

    Reza Akrami

    2016-04-01

    Full Text Available Introduction Bans and restrictions of antibiotics as feed additives in fish culture in many countries have resulted in the increase in studies on alternative dietary supplements such as prebiotics to enhance the health and production of cultured fish. Prebiotics are nondigestible food ingredients that beneficially affect the host by selectively stimulating the growth and/or activity of one or a limited number of bacteria in the colon. In addition, prebiotics promote the growth of lactic acid bacteria that are beneficial to health and lessen the density of pathogenic microorganisms. Because of the conservation of immune system, it is suggested that alternate administration of different immunostimulants may activate different parts of immune system of shrimps and take advantage of different immunostimulants to solve the problem of immunity fatigue and enhance the immunity continuously. However, there is no report on the discontinuous administration of immunostimulants for rainbow trout. Thus, considering the strategic importance of this species, the goal of this study was to assess the effects of discontinuous administration of dietary mannan oligosaccharide and β-1,3-glucan on hematological and blood serum biochemical parameters of rainbow trout. Materials and Methods A 6-week trial was conducted to compare the effects of discontinuous administration of dietary mannan oligosaccharide and β-1,3-glucan on hematological and blood serum biochemical parameters of rainbow trout (Oncorhynchus mykiss. Four feeding strategies were set, including feeding prebiotic-free diet continuously (control, feeding dietary prebiotic continuously (1.5 g kg-1, feeding dietary alternately (one week prebiotic+one week control diet and 2 Day prebiotic+5 Day control diet. Juveniles were fed the experimental diet in rate of 4% of the body weight per day, spread across two feeding time. At the end of the experiment, three fish were sampled randomly from each tank and were

  16. Tenebrio molitor meal in rainbow trout (Oncorhynchus mykiss diets: effects on animal performance, nutrient digestibility and chemical composition of fillets

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    Marco Belforti

    2015-12-01

    Full Text Available This study evaluated the effects of diets containing Tenebrio molitor (TM larvae meal on growth performances, somatic indexes, nutrient digestibility, dorsal muscle proximate and fatty acid (FA compositions of rainbow trout. Three hundred sixty fish were randomly divided into three groups with four replicates each. The groups were fed diets differing in TM inclusion: 0% (TM0, 25% (TM25 and 50% (TM50 as fed weight basis. Weight gain was not affected by treatment. Feeding rate was significantly higher in TM0 than TM50. Feed conversion ratio was significantly higher in TM0 than TM25 and TM50, while an opposite trend was observed for protein efficiency ratio and specific growth rate. The survival rate was significantly lower in TM0 than TM25 and TM50. The apparent digestibility of protein was significantly lower in the TM50 group than the other groups, while the apparent digestibility of dry matter, organic matter and lipids was unaffected by treatment. If compared to control, the protein and lipid contents of fillets were respectively increased and decreased following TM inclusion in the diet. The Σn3/Σn6 FA ratio of fish dorsal muscle was linearly (TM0>TM25>TM50 reduced by TM inclusion in the diet. Results suggested that TM could be used during the growing phase in trout farming; however, additional studies on specific feeding strategies and diet formulations are needed to limit its negative effects on the lipid fraction of fillets.

  17. Determination of Ochratoxin A in the rainbow trout (Oncorhynchus mykiss feed in Chaharmahal Va Bakhtiary province by ELISA assay

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    F Fadaeifard

    2013-02-01

    Full Text Available Ochratoxins are considered as the significant mycotoxins found in animal feeds. Amongst, Ochratoxin A has high pathological consequences on the humans and animals. The aim of present study was to determine the amount of Ochratoxin A in rainbow trout feed produced in Chaharmahal Va Bakhtiary province. For this, four major producers of trout feed were chosen and four different sizes of feed together with one wheat flour sample were obtained from each factory. The samples were transferred to Food Analysis Lab of Shahre-Kord Islamic Azad University. The samples were obtained in three replicates and a total of 60 samples were analyzed for the presence of Ochratoxin A. The analysis was performed by ELISA assay. Results revealed that the quantity of Ochratoxin A in all feed samples were lower than determined contamination level established by Iranian National Standard and EU commission (5µg/kg. However, the contamination levels in all wheat flour samples were higher than defined standard. The amount of Ochratoxin A in samples obtained from various producers was not statistically significant (p

  18. Immunomodulation by heavy metals tested individually or in mixtures in rainbow trout (Oncorhynchus mykiss) exposed in vivo

    Energy Technology Data Exchange (ETDEWEB)

    Sanchez-Dardon, J.; Voccia, I.; Hontela, A.; Chilmonczyk, S.; Dunier, M.; Boermans, H.; Blakley, B.; Fournier, M.

    1999-07-01

    The objective of this study was to evaluate the effect of heavy metals, at environmentally relevant concentrations, on the immune response of rainbow trout. Trout were exposed for 30 d to cadmium chloride (CdCl{sub 2}), mercuric chloride (HgCl{sub 2}), or zinc chloride (ZnCl{sub 2}) either individually or in combinations: CdCl{sub 2}/HgCl{sub 2}, CdCl{sub 2}/ZnCl{sub 2}, HgCl{sub 2}/ZnCl{sub 2}, or CdCl{sub 2}/HgCl{sub 2}/ZnCl{sub 2}. Following the 30-d exposure, parameters of the nonspecific cellular immune response (phagocytosis, respiratory burst, and lymphoblastic proliferation) and of the nonspecific humoral immune response (lysozyme activity and the level of immunoglobulin) were measured. The results obtained indicate that individually, all three metals induce significant immunomodulations. However, the toxicity of mercury or cadmium is significantly reduced in fish simultaneously exposed to zinc, indicating that a protection is afforded by zinc against cadmium- and mercury-induced immunotoxicity.

  19. 17Beta-estradiol affects the response of complement components and survival of rainbow trout (Oncorhynchus mykiss) challenged by bacterial infection.

    Science.gov (United States)

    Wenger, Michael; Sattler, Ursula; Goldschmidt-Clermont, Elinor; Segner, Helmut

    2011-07-01

    Research on the endocrine role of estrogens has focused on the reproductive system, while other potential target systems have been less studied. Here, we investigated the possible immunomodulating role of 17β-estradiol (E2) using rainbow trout (Oncorhynchus mykiss) as a model. The aims of the study were to examine a) whether estrogens can modulate immune gene transcription levels, and b) whether this has functional implications for the resistance of trout towards pathogens. Trout were reared from fertilization until 6 months of age under (1) control conditions, (2) short-term E2-treatment (6-month-old juveniles were fed a diet containing 20 mg E2/kg for 2 weeks), or c) long-term E2-treatment (twice a 2-h-bath-exposure of trout embryos to 400 μg 17β-estradiol (E2)/L, followed by rearing on the E2-spiked diet from start-feeding until 6 months of age). Analysis of plasma estrogen levels indicated that the internal estrogen concentrations of E2-exposed fish were within the physiological range and analysis of hepatic vitellogenin mRNA levels indicated that the E2 administration was effective in activating the endogenous estrogen receptor pathway. However, expression levels of the hepatic complement components C3-1, C3-3, and Factor H were not affected by E2-treatment. In a next step, 6-month-old juveniles were challenged with pathogenic bacteria (Yersinia ruckeri). In control fish, this bacterial infection resulted in significant up-regulation of the mRNA levels of hepatic complement genes (C3-1, C3-3, Factor B, Factor H), while E2-treated fish showed no or significantly lower up-regulation of the complement gene transcription levels. Apparently, the E2-treated trout had a lower capacity to activate their immune system to defend against the bacterial infection. This interpretation is corroborated by the finding that survival of E2-treated fish under bacterial challenge was significantly lower than in the control group. In conclusion, the results from this study

  20. Gastrointestinal assimilation of Cu during digestion of a single meal in the freshwater rainbow trout (Oncorhynchus mykiss).

    Science.gov (United States)

    Nadella, Sunita R; Bucking, Carol; Grosell, Martin; Wood, Chris M

    2006-08-01

    Gastrointestinal processing and assimilation of Cu in vivo was investigated by sequential chyme analysis over a 72 h period following ingestion of a single satiation meal (3% body weight) of commercial trout food (Cu content=0.42 micromol g(-1)) by adult rainbow trout. Leaded glass ballotini beads incorporated into the food and detected by X-ray radiography were employed as an inert marker in order to quantify net Cu absorption or secretion in various parts of the tract. Cu concentrations in the supernatant (fluid phase) fell from about 0.06 micromol mL(-1) (63 microM) in the stomach at 2 h to about 0.003 micromol mL(-1) (3 microM) in the posterior intestine at 72 h. Cu concentrations in the solid phase were 10 to 30-fold higher than in the fluid phase, and increased about 4-fold from the stomach at 2 h to the posterior intestine at 72 h. By reference to the inert marker, overall net Cu absorption from the ingested food by 72 h was about 50%. The mid-intestine, and posterior intestine emerged as important sites of net Cu and water absorption and a potential role for the stomach in this process was also indicated. The anterior intestine was a site of large net Cu addition to the chyme, probably due to large net additions of Cu-containing fluids in the form of bile and other secretions in this segment. The results provide valuable information about sites of Cu absorption and realistic concentrations of Cu in chyme fluid for future in vitro mechanistic studies on Cu transport in the trout gastrointestinal tract.

  1. Toxicity of single walled carbon nanotubes to rainbow trout (Oncorhynchus mykiss): Respiratory toxicity, organ pathologies, and other physiological effects

    International Nuclear Information System (INIS)

    Smith, Catherine J.; Shaw, Benjamin J.; Handy, Richard D.

    2007-01-01

    Mammalian studies have raised concerns about the toxicity of carbon nanotubes (CNTs), but there is very limited data on ecotoxicity to aquatic life. We describe the first detailed report on the toxicity of single walled carbon nanotubes (SWCNT) to rainbow trout, using a body systems approach. Stock solutions of dispersed SWCNT were prepared using a combination of solvent (sodium dodecyl sulphate, SDS) and sonication. A semi-static test system was used to expose rainbow trout to either a freshwater control, solvent control, 0.1, 0.25 or 0.5 mg l -1 SWCNT for up to 10 days. SWCNT exposure caused a dose-dependent rise in ventilation rate, gill pathologies (oedema, altered mucocytes, hyperplasia), and mucus secretion with SWCNT precipitation on the gill mucus. No major haematological or blood disturbances were observed in terms of red and white blood cell counts, haematocrits, whole blood haemoglobin, and plasma Na + or K + . Tissue metal levels (Na + , K + , Ca 2+ , Cu, Zn and Co) were generally unaffected. However some dose-dependent changes in brain and gill Zn or Cu were observed (but not tissue Ca 2+ ), that were also partly attributed to the solvent. SWCNT exposure caused statistically significant increases in Na + K + -ATPase activity in the gills and intestine, but not in the brain. Thiobarbituric acid reactive substances (TBARS) showed dose-dependent and statistically significant decreases especially in the gill, brain and liver during SWCNT exposure compared to controls. SWCNT exposure caused statistically significant increases in the total glutathione levels in the gills (28%) and livers (18%), compared to the solvent control. Total glutathione in the brain and intestine remained stable in all treatments. Pathologies in the brain included possible aneurisms or swellings on the ventral surface of the cerebellum. Liver cells exposed to SWCNT showed condensed nuclear bodies (apoptotic bodies) and cells in abnormal nuclear division. Overt fatty change or wide

  2. Toxicity of single walled carbon nanotubes to rainbow trout (Oncorhynchus mykiss): Respiratory toxicity, organ pathologies, and other physiological effects

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Catherine J. [Ecotoxicology and Stress Biology Research Group, School of Biological Sciences, University of Plymouth, Drake Circus, Plymouth PL4 8AA (United Kingdom); Shaw, Benjamin J. [Ecotoxicology and Stress Biology Research Group, School of Biological Sciences, University of Plymouth, Drake Circus, Plymouth PL4 8AA (United Kingdom); Handy, Richard D. [Ecotoxicology and Stress Biology Research Group, School of Biological Sciences, University of Plymouth, Drake Circus, Plymouth PL4 8AA (United Kingdom)]. E-mail: rhandy@plymouth.ac.uk

    2007-05-01

    Mammalian studies have raised concerns about the toxicity of carbon nanotubes (CNTs), but there is very limited data on ecotoxicity to aquatic life. We describe the first detailed report on the toxicity of single walled carbon nanotubes (SWCNT) to rainbow trout, using a body systems approach. Stock solutions of dispersed SWCNT were prepared using a combination of solvent (sodium dodecyl sulphate, SDS) and sonication. A semi-static test system was used to expose rainbow trout to either a freshwater control, solvent control, 0.1, 0.25 or 0.5 mg l{sup -1} SWCNT for up to 10 days. SWCNT exposure caused a dose-dependent rise in ventilation rate, gill pathologies (oedema, altered mucocytes, hyperplasia), and mucus secretion with SWCNT precipitation on the gill mucus. No major haematological or blood disturbances were observed in terms of red and white blood cell counts, haematocrits, whole blood haemoglobin, and plasma Na{sup +} or K{sup +}. Tissue metal levels (Na{sup +}, K{sup +}, Ca{sup 2+}, Cu, Zn and Co) were generally unaffected. However some dose-dependent changes in brain and gill Zn or Cu were observed (but not tissue Ca{sup 2+}), that were also partly attributed to the solvent. SWCNT exposure caused statistically significant increases in Na{sup +}K{sup +}-ATPase activity in the gills and intestine, but not in the brain. Thiobarbituric acid reactive substances (TBARS) showed dose-dependent and statistically significant decreases especially in the gill, brain and liver during SWCNT exposure compared to controls. SWCNT exposure caused statistically significant increases in the total glutathione levels in the gills (28%) and livers (18%), compared to the solvent control. Total glutathione in the brain and intestine remained stable in all treatments. Pathologies in the brain included possible aneurisms or swellings on the ventral surface of the cerebellum. Liver cells exposed to SWCNT showed condensed nuclear bodies (apoptotic bodies) and cells in abnormal nuclear

  3. Effect of β-1.3/1.6-D-glucan derived from oyster mushroom Pleurotus ostreatus on biometrical, haematological, biochemical, and immunological indices in rainbow trout (Oncorhynchus mykiss).

    Science.gov (United States)

    Dobsikova, Radka; Blahova, Jana; Franc, Ales; Jakubik, Juraj; Mikulikova, Ivana; Modra, Helena; Novotna, Kamila; Svobodova, Zdenka

    2012-01-01

    Effect of long-term oral administration of three different concentrations (0.5, 1.0, and 2.0%) of micronized β-1.3/1.6-D-glucan derived from oyster mushroom (Pleurotus ostreatus, Hiratake) on biometrical, haematological, biochemical, and immunological indices of half-year-old rainbow trout (Oncorhynchus mykiss) was assessed in the study. Rainbow trout were feed commercial feed pellets containing β-1.3/1.6-D-glucan in the concentrations of 0.5, 1.0, and 2.0% for 85 days. Biometrical indices consisted in total and standard length, body and liver weight, from which derived somatic parameters such as Fulton´s condition factor and hepatosomatic index were calculated. Haematological parameters were evaluated according to unified methods for haematological examination in fish. Plasma biochemical profile was analysed using biochemical analyser Konelab 20i and Easy Lyte Analyzer. A phagocyte cells metabolic activity (induced chemiluminescence of phagocytes) was determined as an immunological parameter by a microplate luminometric method on Immunotech LM-01T. No clinical signs of behavioral, respiratory, or neurologic distress were observed in rainbow trout. Fish showed normal feeding behavior. As for biometric parameters, no significant changes in total and standard length, body weight, liver weight, as well as in condition factor and hepatosomatic index of experimental and control fish were found. In the course of the study, weight gains in rainbow trout were similar and continuous. Shifts in PCV (pglucose, lactate, total protein, cholesterol, calcium, natrium, potassium (all p<0.05), albumins and chlorides (both p<0.01), as well as catalytic activities of ALT and AST (both p<0.05) were changed in the course of the study. A phagocyte cells metabolic activity (luminol-induced chemiluminescence) in rainbow trout was not altered by oyster mushroom β-1.3/1.6-D-glucan administration. After long-term oral administration of three concentrations of micronized β-1.3/1.6-D

  4. Species-specific sensitivity to selenium-induced impairment of cortisol secretion in adrenocortical cells of rainbow trout (Oncorhynchus mykiss) and brook trout (Salvelinus fontinalis)

    International Nuclear Information System (INIS)

    Miller, L.L.; Hontela, A.

    2011-01-01

    Species differences in physiological and biochemical attributes exist even among closely related species and may underlie species-specific sensitivity to toxicants. Rainbow trout (RT) are more sensitive than brook trout (BT) to the teratogenic effects of selenium (Se), but it is not known whether all tissues exhibit this pattern of vulnerability. In this study, primary cultures of RT and BT adrenocortical cells were exposed to selenite (Na 2 SO 3 ) and selenomethionine (Se-Met) to compare cell viability and ACTH-stimulated cortisol secretion in the two fish species. Cortisol, the primary stress hormone in fish, facilitates maintenance of homeostasis when fish are exposed to stressors, including toxicants. Cell viability was not affected by Se, but selenite impaired cortisol secretion, while Se-Met did not (RT and BT EC 50 > 2000 mg/L). RT cells were more sensitive (EC 50 = 8.7 mg/L) to selenite than BT cells (EC 50 = 90.4 mg/L). To identify the targets where Se disrupts cortisol synthesis, selenite-impaired RT and BT cells were stimulated with ACTH, dbcAMP, OH-cholesterol, and pregnenolone. Selenite acted at different steps in the cortisol biosynthesis pathway in RT and BT cells, confirming a species-specific toxicity mechanism. To test the hypothesis that oxidative stress mediates Se-induced toxicity, selenite-impaired RT cells were exposed to NAC, BSO and antioxidants (DETCA, ATA, Vit A, and Vit E). Inhibition of SOD by DETCA enhanced selenite-induced cortisol impairment, indicating that oxidative stress plays a role in Se toxicity; however, modifying GSH content of the cells did not have an effect. The results of this study, with two closely related salmonids, provided additional evidence for species-specific differences in sensitivity to Se which should be considered when setting thresholds and water quality guidelines. - Research Highlights: → We investigated species-specific sensitivity to Se in trout adrenocortical cells. → Selenite, not Se-Met, disrupts

  5. Substrate mobilization and hormonal changes in rainbow trout (Oncorhynchus mykiss, L) and common carp (Cyprinus carpio, L) during deep hypoxia and subsequent recovery

    NARCIS (Netherlands)

    VanRaaij, MTM; VandenThillart, GEEJM; Vianen, GJ; Pit, DSS; Balm, PHM; Steffens, B

    1996-01-01

    Common carp (at 20 degrees C) and rainbow trout (at 15 degrees C) were fitted with an indwelling cannula in the dorsal aorta. The fish were exposed to a controlled decline of water pO(2) followed by 90 min deep hypoxia at 0.3 kPa (carp) or 4.8 kPa (trout). Thereafter, normoxic recovery was monitored

  6. Toxicity of titanium dioxide nanoparticles to rainbow trout (Oncorhynchus mykiss): Gill injury, oxidative stress, and other physiological effects

    Energy Technology Data Exchange (ETDEWEB)

    Federici, Gillian; Shaw, Benjamin J. [Ecotoxicology and Stress Biology Research Group, School of Biological Sciences, University of Plymouth, Drake Circus, Plymouth PL4 8AA (United Kingdom); Handy, Richard D. [Ecotoxicology and Stress Biology Research Group, School of Biological Sciences, University of Plymouth, Drake Circus, Plymouth PL4 8AA (United Kingdom)], E-mail: rhandy@plymouth.ac.uk

    2007-10-30

    Mammalian and in vitro studies have raised concerns about the toxicity of titanium dioxide nanoparticles (TiO{sub 2} NPs), but there are very limited data on ecotoxicity to aquatic life. This paper is an observational study where we aim to describe the toxicity of TiO{sub 2} NPs to the main body systems of rainbow trout. Stock solutions of dispersed TiO{sub 2} NPs were prepared by sonication without using solvents. A semi-static test system was used to expose rainbow trout to either a freshwater control, 0.1, 0.5, or 1.0 mg l{sup -1} TiO{sub 2} NPs for up to 14 days. Exposure to TiO{sub 2} NPs caused some gill pathologies including oedema and thickening of the lamellae. No major haematological or blood disturbances were observed in terms of red and white blood cell counts, haematocrit values, whole blood haemoglobin, and plasma Na{sup +} or K{sup +} concentrations. Tissue metal levels (Na{sup +}, K{sup +}, Ca{sup 2+} and Mn) were generally unaffected. However, some exposure concentration-dependent changes in tissue Cu and Zn levels were observed, especially in the brain. Exposure to TiO{sub 2} NPs caused statistically significant decreases in Na{sup +}K{sup +}-ATPase activity (ANOVA, P < 0.05) in the gills and intestine, and a trend of decreasing enzyme activity in the brain (the latter was not statistically significant). Thiobarbituric acid reactive substances (TBARS) showed exposure concentration-dependent and statistically significant (ANOVA or Kruskal-Wallis test, P < 0.05) increases (two-fold or more) in the gill, intestine and brain, but not the liver during exposure to TiO{sub 2} NPs compared to controls. TiO{sub 2} NP exposure caused statistically significant (ANOVA, P < 0.05) increases in the total glutathione levels in the gills, but depletion of hepatic glutathione compared to controls. Total glutathione levels in the brain and intestine were unaffected. Liver cells exposed to TiO{sub 2} NPs showed minor fatty change and lipidosis, and some hepatocytes

  7. Purified deoxynivalenol or feed restriction reduces mortality in rainbow trout, Oncorhynchus mykiss (Walbaum), with experimental bacterial coldwater disease but biologically relevant concentrations of deoxynivalenol do not impair the growth of Flavobacterium psychrophilum.

    Science.gov (United States)

    Ryerse, I A; Hooft, J M; Bureau, D P; Hayes, M A; Lumsden, J S

    2015-09-01

    Diets containing deoxynivalenol (DON) were fed to rainbow trout Oncorhynchus mykiss (Walbaum) for 4 weeks followed by experimental infection (intraperitoneal) with Flavobacterium psychrophilum (4.1 × 10(6) colony-forming units [CFU] mL(-1) ). Mortality of rainbow trout fed either 6.4 mg kg(-1) DON or trout pair-fed the control diet was significantly reduced (P trout fed the control diet to apparent satiation (trout were fed one of three experimental diets; a control diet, a diet produced with corn naturally contaminated with DON (3.3 mg kg(-1) DON) or a diet containing purified DON (3.8 mg kg(-1) ); however, these fish were not experimentally infected. The presence of DON resulted in significant reduction (P trout fed diets containing purified DON (3.8 mg kg(-1) ) was significantly higher (P < 0.05) at 35 day post-exposure compared with controls. The antimicrobial activity of DON was examined by subjecting F. psychrophilum in vitro to serial dilutions of the chemical. Complete inhibition occurred at a concentration of 75 mg L(-1) DON, but no effect was observed below this concentration (0-30 mg L(-1) ). © 2014 John Wiley & Sons Ltd.

  8. Experimental evidence for direct in situ binding of IgM and IgT to early trophonts of Ichthyophthirius multifiliis (Fouquet) in the gills of rainbow trout, Oncorhynchus mykiss (Walbaum)

    DEFF Research Database (Denmark)

    Jørgensen, Louise von Gersdorff; Heinecke, Rasmus Demuth; Skjødt, K

    2011-01-01

    Freshwater fish are able to mount a protective immune response against the parasite Ichthyophthirius multifiliis (Ich) following a non-lethal exposure. Factors involved in immunity comprise cellular and humoral factors, but antibodies have been suggested to play a prominent role in protection....... However, host antibodies have not yet been demonstrated to bind to the parasite in situ. By the use of immunohistochemical techniques, this study demonstrated that IgT and IgM bind to surface structures, including cilia, on the early feeding stage of the parasite in the gills of immune rainbow trout......, Oncorhynchus mykiss, shortly (2 h) after invasion. No binding of IgT and no or only a weak binding of IgM was observed on the parasites in the gills of similarly exposed but naïve rainbow trout. This study indicates that antibodies play an important part in the protection of immune fish against Ich although...

  9. Presence of specific growth hormone binding sites in rainbow trout (Oncorhynchus mykiss) tissues: characterization of the hepatic receptor

    Energy Technology Data Exchange (ETDEWEB)

    Yao, K.; Niu, P.D.; Le Gac, F.; Le Bail, P.Y. (Laboratoire de Physiologie des Poissons, INRA, Rennes, (France))

    1991-01-01

    The present work outlines the presence of specific binding for chinook salmon growth hormone (sGH) in different tissue preparations of rainbow trout. Optimal incubation conditions (pH, Tris, MgCl{sub 2}) were determined. Specific binding was very sensitive to salt concentration during incubation. The specific binding reached a plateau after 15 and 25 hr of incubation at 12 and 4 {degree}. At 20 {degree}, specific and nonspecific binding were not stable. Specific binding dissociation was slower than association and was only partial. The binding was saturable (Bmax = 187 +/- 167 pmol), of high affinity (Ka = 2.4 +/- 0.8 10(9) M-1), and very specific for GH, properties which are in agreement with the characteristics of hormonal receptors. Sea bream and mammalian GH appeared 2- and 30-fold, respectively, less potent than cold sGH2 for displacing {sup 125}I-sGH2. Tissue preparations from ovary, testis, fat, skin, cartilage, gill, blood pellet, brain, spleen, kidney, and muscle showed significant saturable binding.

  10. A simple fish physiological model for radioecologists exemplified for 54Mn direct transfer and rainbow trout (Oncorhynchus mykiss W.)

    International Nuclear Information System (INIS)

    Garnier-Laplace, Jacqueline; Adam, Christelle; Lathuilliere, Thierry; Baudin, Jean-pierre; Clabaut, Mathieu

    2000-01-01

    A simple kinetic model for the transfer of radionuclide to freshwater fish was formulated based on physiological (blood and flow rates), anatomical (volume of tissue compartments) and thermodynamic (tissue-to-blood partition coefficients) parameters. The present study describes 54 Mn direct transfer to young rainbow trout and exemplifies this new approach for radioecology. The model was calibrated on uptake and depuration kinetics datasets obtained for 14 organs/tissues during a 12-week experiment. Organs were classified into three compartments: an input compartment (gills), a distribution/reservoir compartment (muscles, skeleton and skin) and an excretional function compartment (digestive system and liver). For the three compartments, the partition coefficients and the residence time of the pollutant were, respectively: 161 and 4 h, 87 and 1.5 days, and 1465 and 14 days. As an indirect validation technique, a steady-state concentration factor was calculated for the whole organism from the partition coefficient values and fractional volumes of the compartment. The value of 8 l kg -1 w.w. is similar to those reported in the literature

  11. A vegetable oil feeding history affects digestibility and intestinal fatty acid uptake in juvenile rainbow trout Oncorhynchus mykiss.

    Science.gov (United States)

    Geurden, Inge; Jutfelt, Fredrik; Olsen, Rolf-Erik; Sundell, Kristina S

    2009-04-01

    Future expansion of aquaculture relies on the use of alternatives to fish oil in fish feed. This study examined to what extent the nature of the feed oil affects intestinal lipid uptake properties in rainbow trout. The fish were fed a diet containing fish (FO), rapeseed (RO) or linseed (LO) oil for 8 weeks after which absorptive properties were assessed. Differences in digestibility due to feed oil history were measured using diet FO with an indigestible marker. Intestinal integrity, paracellular permeability, in vitro transepithelial fatty acid transport (3H-18:3n-3 and 14C-16:0) and their incorporation into intestinal epithelia were compared using Ussing chambers. Feed oil history did not affect the triacylglycerol/phosphatidylcholine ratio (TAG/PC) of the newly synthesized lipids in the segments. The lower TAG/PC ratio with 16:0 (2:1) than with 18:3 (10:1) showed the preferential incorporation of 16:0 into polar lipids. The FO-feeding history decreased permeability and increased transepithelial resistance of the intestinal segments. Transepithelial passage rates of 18:3n-3 were higher when pre-fed LO compared to RO or FO. Similarly, pre-feeding LO increased apparent lipid and fatty acid digestibilities compared to RO or FO. These results demonstrate that the absorptive intestinal functions in fish can be altered by the feed oil history and that the effect remains after a return to a standard fish oil diet.

  12. Presence of specific growth hormone binding sites in rainbow trout (Oncorhynchus mykiss) tissues: characterization of the hepatic receptor

    International Nuclear Information System (INIS)

    Yao, K.; Niu, P.D.; Le Gac, F.; Le Bail, P.Y.

    1991-01-01

    The present work outlines the presence of specific binding for chinook salmon growth hormone (sGH) in different tissue preparations of rainbow trout. Optimal incubation conditions (pH, Tris, MgCl 2 ) were determined. Specific binding was very sensitive to salt concentration during incubation. The specific binding reached a plateau after 15 and 25 hr of incubation at 12 and 4 degree. At 20 degree, specific and nonspecific binding were not stable. Specific binding dissociation was slower than association and was only partial. The binding was saturable (Bmax = 187 +/- 167 pmol), of high affinity (Ka = 2.4 +/- 0.8 10(9) M-1), and very specific for GH, properties which are in agreement with the characteristics of hormonal receptors. Sea bream and mammalian GH appeared 2- and 30-fold, respectively, less potent than cold sGH2 for displacing 125 I-sGH2. Tissue preparations from ovary, testis, fat, skin, cartilage, gill, blood pellet, brain, spleen, kidney, and muscle showed significant saturable binding

  13. Effects of irradiated Ergosan on the growth performance and mucus biological components of rainbow trout Oncorhynchus mykiss

    Science.gov (United States)

    Sheikhzadeh, Najmeh; Chehrara, Fatemeh; Heidarieh, Marzieh; Nofouzi, Katayoon; Baradaran, Behzad

    2016-01-01

    Effects of irradiated and non-irradiated Ergosan extract (alginic acid) on rainbow trout growth performance and skin mucosal immunity were compared. Ergosan was irradiated at 30 kGy in a cobalt-60 irradiator. A total of 252 fish (128.03±9.4 g) were randomly divided into four equal groups, given the basal diet either unsupplemented with Ergosan (control group) or supplemented with crude Ergosan (5 g/kg), ethanol-extracted Ergosan (0.33 g/kg) or irradiated Ergosan (0.33 g/kg) according to this protocol: basal diet for 15 days, treatment diet for 15 days, basal diet for 10 days and treatment diet for 15 days. Highest growth performance was observed in fish fed irradiated Ergosan ( P <0.05). Dietary administration of different Ergosan types did not cause any changes in mucus protein level, but improved alkaline phosphatase level and hemagglutination titer compared with the control (basal diet without Ergosan) on day 55 of feeding trial ( P <0.05). Furthermore, the highest value of lysozyme activity was observed in gamma-irradiated Ergosan on day 55. In conclusion, gamma-irradiated Ergosan at 0.33 g/kg was found to improve growth performance and mucus biological components significantly in comparison with the control group (basal diet without Ergosan).

  14. Dissolved oxygen and dietary phosphorus modulate utilization and effluent partitioning of phosphorus in rainbow trout (Oncorhynchus mykiss) aquaculture

    International Nuclear Information System (INIS)

    McDaniel, Nichole K.; Sugiura, Shozo H.; Kehler, Thomas; Fletcher, John W.; Coloso, Relicardo M.; Weis, Peddrick; Ferraris, Ronaldo P.

    2005-01-01

    Phosphorus (P) is the limiting nutrient in freshwater primary production, and excessive levels cause premature eutrophication. P levels in aquaculture effluents are now tightly regulated. Increasing our understanding of waste P partitioning into soluble, particulate, and settleable fractions is important in the management of effluent P. When water supply is limited, dissolved oxygen concentration (DO) decreases below the optimum levels. Therefore, we studied effects of DO (6 and 10 mg/L) and dietary P (0.7 and 1.0% P) on rainbow trout growth, P utilization, and effluent P partitioning. Biomass increased by 40% after 3 weeks. DO at 10 mg/L significantly increased fish growth and feed efficiency, and increased the amount of P in the soluble fraction of the effluent. Soluble effluent P was greater in fish fed 1.0% P. DO increases fish growth and modulates P partitioning in aquaculture effluent. - Dissolved oxygen concentration not only influences fish growth rate, but also affects dietary phosphorus utilization by fish in intensive aquaculture

  15. The effects of riverine physical complexity on anadromy and genetic diversity in steelhead or rainbow trout Oncorhynchus mykiss around the Pacific Rim.

    Science.gov (United States)

    McPhee, M V; Whited, D C; Kuzishchin, K V; Stanford, J A

    2014-07-01

    This study explored the relationship between riverine physical complexity, as determined from remotely sensed metrics, and anadromy and genetic diversity in steelhead or rainbow trout Oncorhynchus mykiss. The proportion of anadromy (estimated fraction of individuals within a drainage that are anadromous) was correlated with riverine complexity, but this correlation appeared to be driven largely by a confounding negative relationship between drainage area and the proportion of anadromy. Genetic diversity decreased with latitude, was lower in rivers with only non-anadromous individuals and also decreased with an increasing ratio of floodplain area to total drainage area. Anadromy may be less frequent in larger drainages due to the higher cost of migration associated with reaches farther from the ocean, and the negative relationship between genetic diversity and floodplain area may be due to lower effective population size resulting from greater population fluctuations associated with higher rates of habitat turnover. Ultimately, the relationships between riverine physical complexity and migratory life history or genetic diversity probably depend on the spatial scale of analysis. © 2014 The Fisheries Society of the British Isles.

  16. Serum disposition of bovine lactoferrin after oral and anal administration and its proteolytic cleavage by gastric transit in rainbow trout (Oncorhynchus mykiss W.).

    Science.gov (United States)

    Cecchini, Stefano; Caputo, Anna R

    2009-01-01

    Several studies have shown an immunomodulatory effect of orally administered bovine lactoferrin (LF) in fish, but the process of digestion was not characterized. In the present study, we investigated the fate of bovine LF after oral and anal administration, and studied the appearance of intact LF in the bloodstream and its proteolytic attack during the gastric transit in rainbow trout (Oncorhynchus mykiss) held at 9 degrees C and 18 degrees C. Data obtained showed the presence of intact bovine LF in the bloodstream only after anal administration in fish held at 18 degrees C and the presence of several peptides derived from bovine LF in the gastric content. Immunoblotting analysis showed that only a part of bovine LF-derived peptides reacted with the applied anti-bovine LF antibody. The concentration of intact bovine LF, after 30 min of administration, in the gastric content of fish reared at 18 degrees C, being extremely low, if any, led us to suspect that the immunoregulatory effect of dietary bovine LF shown in fish by several authors is not due to the intact form but to bioactive fragments, originated by the proteolytic attack during the gastric transit, as demonstrated in higher vertebrates.

  17. Molecular evidence and physiological characterization of iron absorption in isolated enterocytes of rainbow trout (Oncorhynchus mykiss): Implications for dietary cadmium and lead absorption

    International Nuclear Information System (INIS)

    Kwong, Raymond W.M.; Andres, Jose A.; Niyogi, Som

    2010-01-01

    Recent studies suggested the probable involvement of an apical iron (Fe 2+ ) transporter, the divalent metal transporter-1 (DMT1), in the uptake of several divalent metals in fish. The present study examined the gastrointestinal expression of the DMT1 gene, and investigated the kinetics of Fe 2+ uptake and its interactions with cadmium and lead in isolated enterocytes of freshwater rainbow trout (Oncorhynchus mykiss). The expressions of two DMT1 isoforms (Nramp-β and -γ) were recorded along the entire gastrointestinal tract of fish as well as in the enterocytes. Fe 2+ uptake in isolated enterocytes was saturable and sensitive to the proton gradient and membrane potential, suggesting DMT1-mediated transport. Both cadmium and lead inhibited Fe 2+ uptake in isolated enterocytes in a concentration-dependent manner, and lead appeared to be a stronger inhibitor than cadmium. The kinetic characterization of Fe 2+ uptake revealed that the apparent affinity of uptake was significantly decreased (increased K m ) in the presence of either cadmium or lead, whereas the maximum uptake rate (J max ) remained unchanged-indicating that the interaction between Fe 2+ and cadmium or lead is competitive in nature. Overall, our study suggests that the uptake of dietary cadmium and lead may occur via the iron-transporting pathway in fish.

  18. High-fat diet reduces local myostatin-1 paralog expression and alters skeletal muscle lipid content in rainbow trout, Oncorhynchus mykiss

    Science.gov (United States)

    Galt, Nicholas J.; Froehlich, Jacob Michael; Meyer, Ben M.; Barrows, Frederic T.; Biga, Peggy R.

    2014-01-01

    Muscle growth is an energetically demanding process that is reliant on intramuscular fatty acid depots in most fishes. The complex mechanisms regulating this growth and lipid metabolism are of great interest for human health and aquaculture applications. It is well established that the skeletal muscle chalone, myostatin, plays a role in lipid metabolism and adipogenesis in mammals; however, this function has not been fully assessed in fishes. We therefore examined the interaction between dietary lipid levels and myostatin expression in rainbow trout (Oncorhynchus mykiss). Five-weeks of high-fat (HFD; 25% lipid) dietary intake increased white muscle lipid content, and decreased circulating glucose levels and hepatosomatic index when compared to low-fat diet (LFD; 10% lipid) intake. In addition HFD intake reduced myostatin-1a and -1b expression in white muscle and myostatin-1b expression in brain tissue. Characterization of the myostatin-1a, -1b, and -2a promoters revealed putative binding sites for a subset of transcription factors associated with lipid metabolism. Taken together, these data suggest that HFD may regulate myostatin expression through cis-regulatory elements sensitive to increased lipid intake. Further, these findings provide a framework for future investigations of mechanisms describing the relationships between myostatin and lipid metabolism in fish. PMID:24264425

  19. Tissue microenvironments in the nasal epithelium of rainbow trout (Oncorhynchus mykiss) define two distinct CD8α+ cell populations and establish regional immunity

    Science.gov (United States)

    Sepahi, Ali; Casadei, Elisa; Tacchi, Luca; Muñoz, Pilar; LaPatra, Scott E.; Salinas, Irene

    2016-01-01

    Mucosal surfaces require balancing different physiological roles and immune functions. In order to effectively achieve multifunctionality, mucosal epithelia have evolved unique microenvironments that create unique regional immune responses without impairing other normal physiological functions. Whereas examples of regional immunity are known in other mucosal epithelia, to date, no immune microenvironments have been described in the nasal mucosa, a site where the complex functions of olfaction and immunity need to be orchestrated. In this study we identified for the first time the presence of CD8α+ cells in the rainbow trout (Oncorhynchus mykiss) nasal epithelium. Nasal CD8α+ cells display a distinct phenotype suggestive of CD8+ T cells with high integrin β2 expression. Importantly, nasal CD8α+ cells are located in clusters at the mucosal tip of each olfactory lamella but scattered in the neuroepithelial region. The grouping of CD8α+ cells may be explained by the greater expression of CCL19, ICAM-1, and VCAM-1 in the mucosal tip compared to the neuroepithelium. Whilst viral antigen uptake occurred via both tip and lateral routes, tip resident MHC-II+ cells are located significantly closer to the lumen of the nasal cavity than their neuroepithelial counterparts, therefore having quicker access to invading pathogens. Our studies reveal for the first time compartmentalized mucosal immune responses within the nasal mucosa of a vertebrate species, a strategy that likely optimizes local immune responses while protecting olfactory sensory functions. PMID:27798156

  20. Molecular evidence and physiological characterization of iron absorption in isolated enterocytes of rainbow trout (Oncorhynchus mykiss): Implications for dietary cadmium and lead absorption

    Energy Technology Data Exchange (ETDEWEB)

    Kwong, Raymond W.M. [Toxicology Centre, University of Saskatchewan, Saskatoon, SK., S7N 5B3 (Canada); Andres, Jose A. [Department of Biology, University of Saskatchewan, Saskatoon, SK., S7N 5E2 (Canada); Niyogi, Som, E-mail: som.niyogi@usask.ca [Department of Biology, University of Saskatchewan, Saskatoon, SK., S7N 5E2 (Canada)

    2010-09-01

    Recent studies suggested the probable involvement of an apical iron (Fe{sup 2+}) transporter, the divalent metal transporter-1 (DMT1), in the uptake of several divalent metals in fish. The present study examined the gastrointestinal expression of the DMT1 gene, and investigated the kinetics of Fe{sup 2+} uptake and its interactions with cadmium and lead in isolated enterocytes of freshwater rainbow trout (Oncorhynchus mykiss). The expressions of two DMT1 isoforms (Nramp-{beta} and -{gamma}) were recorded along the entire gastrointestinal tract of fish as well as in the enterocytes. Fe{sup 2+} uptake in isolated enterocytes was saturable and sensitive to the proton gradient and membrane potential, suggesting DMT1-mediated transport. Both cadmium and lead inhibited Fe{sup 2+} uptake in isolated enterocytes in a concentration-dependent manner, and lead appeared to be a stronger inhibitor than cadmium. The kinetic characterization of Fe{sup 2+} uptake revealed that the apparent affinity of uptake was significantly decreased (increased K{sub m}) in the presence of either cadmium or lead, whereas the maximum uptake rate (J{sub max}) remained unchanged-indicating that the interaction between Fe{sup 2+} and cadmium or lead is competitive in nature. Overall, our study suggests that the uptake of dietary cadmium and lead may occur via the iron-transporting pathway in fish.

  1. Epidermal response of rainbow trout to Ichthyobodo necator

    DEFF Research Database (Denmark)

    Chettri, Jiwan Kumar; Kuhn, Jesper Andreas; Mohammad, Rezkar Jaafar

    2014-01-01

    Infections with the parasitic flagellate Ichthyobodo necator (Henneguy, 1883) cause severe skin and gill disease in rainbow trout Oncorhynchus mykiss (Walbaum, 1792) juveniles. The epidermal disturbances including hyperplasia and mucous cell exhaustion caused by parasitization are known, but no d...

  2. Expression and Functional Characterization of the RIG-I-Like Receptors MDA5 and LGP2 in Rainbow Trout (Oncorhynchus mykiss) ▿ †

    Science.gov (United States)

    Chang, Mingxian; Collet, Bertrand; Nie, Pin; Lester, Katherine; Campbell, Scott; Secombes, Christopher J.; Zou, Jun

    2011-01-01

    The retinoic acid-inducible gene I (RIG-I)-like receptors (RLR) comprise three homologues: RIG-I, melanoma differentiation-associated gene 5 (MDA5), and laboratory of genetics and physiology 2 (LGP2). They activate the host interferon (IFN) system upon recognition of viral RNA pathogen-associated molecular patterns (PAMPs) in the cytoplasm. Bioinformatic analysis of the sequenced vertebrate genomes suggests that the cytosolic surveillance system is conserved in lower vertebrates, and recent functional studies have confirmed that RIG-I is important to fish antiviral immunity. In this study, we have identified MDA5 and LGP2 homologues from rainbow trout Oncorhynchus mykiss and an additional LGP2 variant with an incomplete C-terminal domain of RIG-I. Trout MDA5 and LGP2 were constitutively produced in fibroblast and macrophage cell lines and upregulated by poly(I:C), recombinant IFN, or infection by RNA viruses (viral hemorrhagic septicemia virus and salmon alphavirus) with a single-stranded positive or negative genome. Overexpression of MDA5 and LGP2 but not of the LGP2 variant resulted in significant accumulation of Mx transcripts in cultured cells, which correlated with a marked enhancement of protection against viral infection. These results demonstrate that both MDA5 and LGP2 are important RLRs in host surveillance against infection of both negative and positive viruses and that the LGP2 variant with a deletion of 54 amino acids at the C terminus acts as a negative regulator for LGP2-elicited antiviral signaling by competing for the viral RNA PAMPs. Interestingly, MDA5 expression was not affected by overexpressed LGP2 in transfected cells and vice versa, suggesting that they likely act in parallel as positive regulators for IFN production. PMID:21680521

  3. Effect of modified atmosphere and vacuum packaging on selected chemical parameters of rainbow trout (Oncorhynchus mykiss and carp (Cyprinus carpio cuts freshness

    Directory of Open Access Journals (Sweden)

    Babić Jelena A.

    2014-01-01

    Full Text Available The purpose of food packing in modified atmosphere is to extend its sustainability by preventing both biochemical processes and growth of spoilage bacteria. Gases or their mixtures which are mostly used in the modified atmosphere food packing technology are carbon-dioxide (CO2, oxygen (O2 and nitrogen (N2. The aim of our research was to examine the influence of packaging in modified atmosphere and vacuum on the total volatile basic nitrogen (TVB-N content and pH in muscle of rainbow trout (Oncorhynchus mykiss and common carp (Cyprinus carpio, as well as to determine the most suitable gas mixtures for packing of these freshwater species. Three sample groups of trout and carp cuts were investigated. The first two groups were packaged in modified atmosphere with different gas ratios: 60%CO2+40%N2 (I group and 40%CO2+60%N2 (II group, whereas the samples from third, control group, (III group were vacuum packaged. During trials samples were stored in refrigerator at +3°C. Determination of TVB-N and pH was performed on 1st, 7th and 14th day of storage. The obtained results indicate that the investigated mixtures of gases and vacuum as well had a significant influence on the values of TVB-N in trout and carp cuts samples. The lowest increase in TVB-N was established in trout and carp cuts samples from the group I, whereas the highest increase was established in samples from group III. Statistical significant difference (p < 0,001 between the average values of TVB-N for trout (I group: 18,17 ± 0,93; II group: 20,90 ± 0,81 and III group: 36,18 ± 2,65 mg N/100 g and carp cuts (I group: 26,74 ± 1,48; II group: 30,02 ± 0,31 and III group: 35,10 ± 1,75 mg N/100 g was established on 14th day. The lowest pH value was established in samples packaged in modified atmosphere with 60% CO2 +40% N2 (I group. On 14th day of testing the obtained value was 6,15 ± 0,09 for trout and 5,94 ± 1,11 for carp samples. Increase in pH value in trout samples packed in

  4. Prebiotic effect of fructo–oligosaccharides on growth and physiological state of rainbow trout, Oncorhynchus mykiss (Walbaum

    Directory of Open Access Journals (Sweden)

    Jiří Řehulka

    2011-01-01

    Full Text Available Rainbow trout at an average weight of 240 g were examined for the effect of dietary fructo–oligosaccharides in the diet on their growth and physiological state through selected biochemical parameters of the blood plasma. The prebiotic product Profeed® (experimental group, EG was administered on a continuous basis at a rate of g kg−1 of pellets for 105 days. The best growth performance for the EG was found in 42 days (363 ± 34.7 g vs. 340 ± 36.7 g, P = 0.003 and in 63 days (387 ± 35.6 g vs. 364 ± 42.3 g, P = 0.011. SGR of the fish from the EG was 0.69% and from the control group (CG was 0.70%. The feed conversion level was 0.82 in the EG and 0.86 in the CG. Survival rate was 99% (EG and 98% (CG. The results of the biochemical examination indicate significant differences in the creatinine (28 ± 5.5 vs. 22 ± 3.05 µmol L−1 and the sodium cation (157.9 1.66 vs. 155.7 ± 1.49 mmol L−1 level and in the catalytic concentration of alkaline phosphatase (5.18 ± 1.57 vs. 3.43 ± 0.78 µkat L−1. The positive results of the growth and biochemical tests as well as the favourable feed conversion suggest that it would be worthwhile to test higher concentrations of the Profeed® prebiotic product.

  5. Prevalence and Antimicrobial Resistance Profile of Listeria Species Isolated from Farmed and On-Sale Rainbow Trout ( Oncorhynchus mykiss) in Western Iran.

    Science.gov (United States)

    Rezai, Ramin; Ahmadi, Elham; Salimi, Behnam

    2018-05-01

    Listeria species are important foodborne pathogens, among which L. monocytogenes and L. ivanovii cause human listeriosis. The purpose of this study was to evaluate the incidence and antimicrobial resistance profiles of Listeria species in farmed and on-sale rainbow trout ( Oncorhynchus mykiss) in Kurdistan province, western Iran. A total of 240 fresh rainbow trout fish (120 samples from farms and 120 samples from retail outlets) were collected and analyzed phenotypically for the presence of Listeria. All Listeria isolates were differentiated with molecular techniques, and L. monocytogenes strains were identified to serotype. The antibiotic susceptibility of all Listeria isolates also was determined. Among the 240 samples, 86 (35.83%) were contaminated with Listeria: 32 samples of farmed fish and 54 samples of on-sale fish. The prevalence among the 240 samples was 9.16% (22 samples) for L. monocytogenes, 6.66% (16 samples) for L. ivanovii, 3.75% (9 samples) for L. welshimeri, 4.99% (12 samples) for L. grayi, 7.5% (18 samples) for L. innocua, and 3.75% (9 samples) for L. seeligeri. The prevalences of the human pathogenic strains L. monocytogenes and L. ivanovii were 4.16% (5 samples) and 14.16% (17 samples) in farmed fish and 5.83% (7 samples) and 7.5% (9 samples) in on-sale fish, respectively. Of the 22 L. monocytogenes isolates, 15, 3, and 4 were identified as serotypes 4b, 1/2a, and 1/2b, respectively. The highest rates of antibiotic resistance among the 86 Listeria isolates was observed against tetracycline (62.79% of all isolates), enrofloxacin (56.97%), and ciprofloxacin (38.37%). Very high resistance was also detected against penicillin (36.04%) and ampicillin (34.88%). These results highlight the potential public health threat posed by fish contaminated with Listeria species, including L. monocytogenes, in the west of Iran. Regular monitoring of Listeria contamination, upgrading of sanitary conditions in the fish industry, and prudent use of antibiotics is

  6. Development and comparison of computational models for estimation of absorbed organ radiation dose in rainbow trout (Oncorhynchus mykiss) from uptake of iodine-131

    International Nuclear Information System (INIS)

    Martinez, N.E.; Johnson, T.E.; Capello, K.; Pinder, J.E.

    2014-01-01

    This study develops and compares different, increasingly detailed anatomical phantoms for rainbow trout (Oncorhynchus mykiss) for the purpose of estimating organ absorbed radiation dose and dose rates from 131 I uptake in multiple organs. The models considered are: a simplistic geometry considering a single organ, a more specific geometry employing additional organs with anatomically relevant size and location, and voxel reconstruction of internal anatomy obtained from CT imaging (referred to as CSUTROUT). Dose Conversion Factors (DCFs) for whole body as well as selected organs of O. mykiss were computed using Monte Carlo modeling, and combined with estimated activity concentrations, to approximate dose rates and ultimately determine cumulative radiation dose (μGy) to selected organs after several half-lives of 131 I. The different computational models provided similar results, especially for source organs (less than 30% difference between estimated doses), and whole body DCFs for each model (∼3 × 10 −3 μGy d −1 per Bq kg −1 ) were comparable to DCFs listed in ICRP 108 for 131 I. The main benefit provided by the computational models developed here is the ability to accurately determine organ dose. A conservative mass-ratio approach may provide reasonable results for sufficiently large organs, but is only applicable to individual source organs. Although CSUTROUT is the more anatomically realistic phantom, it required much more resource dedication to develop and is less flexible than the stylized phantom for similar results. There may be instances where a detailed phantom such as CSUTROUT is appropriate, but generally the stylized phantom appears to be the best choice for an ideal balance between accuracy and resource requirements. - Highlights: • Computational models (phantoms) are developed for rainbow trout internal dosimetry. • Phantoms are combined with empirical models for 131 I uptake to estimate dose. • Voxel and stylized phantoms predict

  7. Do polyethylene microplastic beads alter the intestinal uptake of Ag in rainbow trout (Oncorhynchus mykiss)? Analysis of the MP vector effect using in vitro gut sacs.

    Science.gov (United States)

    Khan, Farhan R; Boyle, David; Chang, Elisabeth; Bury, Nicolas R

    2017-12-01

    Microplastic (MP) vector effects have been well described in the literature but surprisingly little is in known about the impact of MPs on the intestinal uptake of contaminants. The present study aimed to determine whether the intestinal fate of Ag was affected by the presence of polyethylene MP beads. Ag (added as 110m Ag) was introduced into the lumen of rainbow trout (Oncorhynchus mykiss) anterior/mid-intestine gut sac preparations as Ag only, Ag and MPs (co-exposure) and Ag-incubated MPs (where Ag was adsorbed to the MP). Results show that after 3 h exposure the distribution of accumulated Ag between the four intestinal compartments (mucus layer, mucosal epithelium, muscle layer and serosal saline) was not affected by either MP condition when compared to Ag alone (p > 0.05, One way ANOVA). Across all treatment groups mucus layer binding dominated (54.2-72.6%) whereas relatively little Ag was transported to the blood compartment (i.e. combined muscle layer and serosal saline compartments, 8.5-15.0%). Accompanying adsorption/desorption studies were performed in relevant media. Over 24 h, 60.6± 2.9% of the available Ag in artificial freshwater adhered to the surface of the PE MPs. In pH adjusted luminal fluids (pH 2.2, 4.1, 7.4 and 9.8) that span the range of conditions encountered within the rainbow trout digestive tract, there was almost complete dissociation at acidic pHs within 3 h (<2% remaining on MPs at both pH 2.2 and pH 4.1). Such pHs are typical of piscine stomach. Based on our finding we suggest that following the ingestion of MPs with adsorbed pollutants, desorption would occur prior to entering the site of uptake. The MPs themselves have no impact on the trans-epithelial transport of the contaminant, but the net result of the MP vector effect is to potentially introduce labile contaminant forms into the intestine. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Nisin Z Production by Lactococcus lactis subsp. cremoris WA2-67 of Aquatic Origin as a Defense Mechanism to Protect Rainbow Trout (Oncorhynchus mykiss, Walbaum) Against Lactococcus garvieae.

    Science.gov (United States)

    Araújo, Carlos; Muñoz-Atienza, Estefanía; Pérez-Sánchez, Tania; Poeta, Patrícia; Igrejas, Gilberto; Hernández, Pablo E; Herranz, Carmen; Ruiz-Zarzuela, Imanol; Cintas, Luis M

    2015-12-01

    Probiotics represent an alternative to chemotherapy and vaccination to control fish diseases, including lactococcosis caused by Lactococcus garvieae. The aims of this study were (i) to determine the in vitro probiotic properties of three bacteriocinogenic Lactococcus lactis subsp. cremoris of aquatic origin, (ii) to evaluate in vivo the ability of L. cremoris WA2-67 to protect rainbow trout (Oncorhynchus mykiss, Walbaum) against infection by L. garvieae, and (iii) to demonstrate the role of nisin Z (NisZ) production as an anti-infective mechanism. The three L. cremoris strains survived in freshwater at 18 °C for 7 days, withstood exposure to pH 3.0 and 10 % (v/v) rainbow trout bile, and showed different cell surface hydrophobicity (37.93-58.52 %). The wild-type NisZ-producer L. cremoris WA2-67 and its non-bacteriocinogenic mutant L. cremoris WA2-67 ∆nisZ were administered orally (10(6) CFU/g) to rainbow trout for 21 days and, subsequently, fish were challenged with L. garvieae CLG4 by the cohabitation method. The fish fed with the bacteriocinogenic strain L. cremoris WA2-67 reduced significantly (p trout against infection with the invasive pathogen L. garvieae and the relevance of NisZ production as an anti-infective mechanism. This is the first report demonstrating the effective in vivo role of LAB bacteriocin (NisZ) production as a mechanism to protect fish against bacterial infection. Our results suggest that the wild-type NisZ-producer strain L. cremoris WA2-67 could be used in fish farming to prevent lactococcosis in rainbow trout.

  9. Constitutive mRNA expression and protein activity levels of nine ABC efflux transporters in seven permanent cell lines derived from different tissues of rainbow trout (Oncorhynchus mykiss).

    Science.gov (United States)

    Fischer, Stephan; Loncar, Jovica; Zaja, Roko; Schnell, Sabine; Schirmer, Kristin; Smital, Tvrtko; Luckenbach, Till

    2011-01-25

    Permanent fish cell lines have become common model systems for determining ecotoxicological effects of pollutants. For these cell lines little is known on the cellular active transport mechanisms that control the amount of a compound entering the cell, such as the MXR (multixenobiotic resistance) system mediated by ATP binding cassette (ABC) transport proteins. Therefore, for toxic evaluation of chemicals with those cells information on MXR is important. We here present data on constitutive mRNA expression and protein activity levels of a series of ABC efflux transporters in seven permanent cell lines derived from liver (RTL-W1; R1) and liver hepatoma (RTH-149), gill (RTgill-W1), gonad (RTG-2), gut (RTgutGC) and brain (RTbrain) of rainbow trout (Oncorhynchus mykiss). In addition to known transporters abcb1 (designated here abcb1a), abcb11, abcc1-3, abcc5 and abcg2, we quantified expression levels of a newly identified abcb1 isoform (abcb1b) and abcc4, previously unknown in trout. Quantitative real time PCR (qPCR) indicated that mRNA of the examined ABC transporters was constitutively expressed in all cell lines. Transporter mRNA expression patterns were similar in all cell lines, with expression levels of abcc transporters being 80 to over 1000 fold higher than for abcg2, abcb1a/b and abcb11 (abcc1-5>abcg2>abcb1a/b, 11). Transporter activity in the cell lines was determined by measuring uptake of transporter type specific fluorescent substrates in the presence of activity inhibitors. The combination of the ABCB1 and ABCC transporter substrate calcein-AM with inhibitors cyclosporine A, PSC833 and MK571 resulted in a concentration-dependent fluorescence increase of up to 3-fold, whereas reversin 205 caused a slight, but not concentration-dependent fluorescence increase. Accumulation of the dyes Hoechst 33342 and 2',7'-dichlorodihydrofluorescein diacetate was basically unchanged in the presence of Ko134 and taurocholate, respectively, indicating low Abcg2 and Abcb11

  10. Selenium Supplementation in Fish: A Combined Chemical and Biomolecular Study to Understand Sel-Plex Assimilation and Impact on Selenoproteome Expression in Rainbow Trout (Oncorhynchus mykiss.

    Directory of Open Access Journals (Sweden)

    Davide Pacitti

    Full Text Available Selenium (Se is an essential oligonutrient, as a component of several Se-containing proteins (selenoproteins, which exert important biological functions within an organism. In livestock, Se-enriched products have been proposed as dietary supplements to be included into functional feeds for animal preventive health care. To this end, it is important to understand the optimal range of concentrations for supplementation and how long it takes to be assimilated into the organism.In this study, rainbow trout (Oncorhynchus mykiss were fed a control diet containing 0.9 g Kg-1 Se or the same diet supplemented with a Se-Yeast product (Sel-Plex to achieve Se concentrations ranging from 1.5-8.9 g Kg-1 for a period of ten weeks. Fish were sampled every two weeks for analysis. The kinetics of Se bioaccumulation and the effects on fish selenoprotein expression was determined in different tissues combining chemical and bimolecular techniques.The Sel-Plex enriched diets did not have any effect on survival and growth performance. The highest Se levels were found in liver and kidney followed by muscle and blood cells. Analysis of the Se concentration factor showed that liver is able to initially regulate the amount of Se accumulated. However, with higher dietary Se level (4.8 and 8.9 g Kg-1 and longer times of exposure (10 weeks, regulation is ineffective and the Se tissue concentration increases. The expression of the selected trout selenoprotein transcripts showed an inverse correlation with Sel-Plex augmentation in most cases. In liver, kidney and blood cells the highest up-regulation of the trout selenoprotein genes was seen mostly in the group fed the diet enriched with the lowest concentration of Sel-Plex (0.5 g Kg-1 for 10 weeks.Sel-Plex may represent an excellent Se supplement to deliver a high level of Se without provoking harm to the fish and to guarantee the maximal absorption of the element. According to our results, a dietary supplementation of Sel

  11. Early feeding of carnivorous rainbow trout (Oncorhynchus mykiss) with a hyperglucidic diet during a short period: effect on dietary glucose utilization in juveniles

    OpenAIRE

    Geurden, Inge; Aramendi, M.; Zambonino Infante, José Luis; Panserat, Stephane

    2007-01-01

    Based on the concept of nutritional programming in higher vertebrates, we tested whether an acute hyperglucidic stimulus during early life could induce a long-lasting effect on carbohydrate utilization in carnivorous rainbow trout. The trout were fed a hyperglucidic diet (60% dextrin) at two early stages of development: either at first feeding Q days, stimulus 1) or after yolk absorption (5 days, stimulus 2). Before and after the hyperglucidic stimulus, they received a commercial diet until j...

  12. Brown Trout removal effects on short-term survival and movement of Myxobolus cerebralis-resistant rainbow trout

    Science.gov (United States)

    Fetherman, Eric R.; Winkelman, Dana L.; Bailey, Larissa L.; Schisler, George J.; Davies, K.

    2015-01-01

    Following establishment of Myxobolus cerebralis (the parasite responsible for salmonid whirling disease) in Colorado, populations of Rainbow Trout Oncorhynchus mykissexperienced significant declines, whereas Brown Trout Salmo trutta densities increased in many locations across the state, potentially influencing the success of M. cerebralis-resistant Rainbow Trout reintroductions. We examined the effects of Brown Trout removal on the short-term (3-month) survival and movement of two crosses of reintroduced, M. cerebralis-resistant Rainbow Trout in the Cache la Poudre River, Colorado. Radio frequency identification passive integrated transponder tags and antennas were used to track movements of wild Brown Trout and stocked Rainbow Trout in reaches where Brown Trout had or had not been removed. Multistate mark–recapture models were used to estimate tagged fish apparent survival and movement in these sections 3 months following Brown Trout removal. A cross between the German Rainbow Trout and Colorado River Rainbow Trout strains exhibited similar survival and movement probabilities in the reaches, suggesting that the presence of Brown Trout did not affect its survival or movement. However, a cross between the German Rainbow Trout and Harrison Lake Rainbow Trout exhibited less movement from the reach in which Brown Trout had been removed. Despite this, the overall short-term benefits of the removal were equivocal, suggesting that Brown Trout removal may not be beneficial for the reintroduction of Rainbow Trout. Additionally, the logistical constraints of conducting removals in large river systems are substantial and may not be a viable management option in many rivers.

  13. Zinc and calcium alter the relationship between mitochondrial respiration, ROS and membrane potential in rainbow trout (Oncorhynchus mykiss) liver mitochondria.

    Science.gov (United States)

    Sharaf, Mahmoud S; Stevens, Don; Kamunde, Collins

    2017-08-01

    At excess levels, zinc (Zn) disrupts mitochondrial functional integrity and induces oxidative stress in aquatic organisms. Although much is known about the modulation of Zn toxicity by calcium (Ca) in fish, their interactions at the mitochondrial level have scarcely been investigated. Here we assessed the individual and combined effects of Zn and Ca on the relationship between mitochondrial respiration, ROS and membrane potential (ΔΨ mt ) in rainbow trout liver mitochondria. We tested if cation uptake through the mitochondrial calcium uniporter (MCU) is a prerequisite for Zn- and/or Ca-induced alteration of mitochondrial function. Furthermore, using our recently developed real-time multi-parametric method, we investigated the changes in respiration, ΔΨ mt , and reactive oxygen species (ROS, as hydrogen peroxide (H 2 O 2 )) release associated with Ca-induced mitochondrial depolarization imposed by transient and permanent openings of the mitochondrial permeability transition pore (mPTP). We found that independent of the MCU, Zn precipitated an immediate depolarization of the ΔΨ mt that was associated with relatively slow enhancement of H 2 O 2 release, inhibition of respiration and reversal of the positive correlation between ROS and ΔΨ mt . In contrast, an equitoxic dose of Ca caused transient depolarization, and stimulation of both respiration and H 2 O 2 release, effects that were completely abolished when the MCU was blocked. Contrary to our expectation that mitochondrial transition ROS Spike (mTRS) would be sensitive to both Zn and Ca, only Ca suppressed it. Moreover, Zn and Ca in combination immediately depolarized the ΔΨ mt , and caused transient and sustained stimulation of respiration and H 2 O 2 release, respectively. Lastly, we uncovered and characterized an mPTP-independent Ca-induced depolarization spike that was associated with exposure to moderately elevated levels of Ca. Importantly, we showed the stimulation of ROS release associated with

  14. Combined effects of cadmium, temperature and hypoxia-reoxygenation on mitochondrial function in rainbow trout (Oncorhynchus mykiss)

    Energy Technology Data Exchange (ETDEWEB)

    Onukwufor, John O.; Stevens, Don; Kamunde, Collins, E-mail: ckamunde@upei.ca

    2017-01-15

    Highlights: • Ternary interactions of Cd, temperature and H-R alter their individual and binary effects on mitochondrial bioenergetics. • Oxidative stress explains many effects of Cd, H-R and temperature on mitochondria. • Cd accumulation does not explain increased sensitivity of mitochondria to multiple stressors. • Cd induces hormetic responses during H-R stress. • Cd at low dose blunts conversion of complex I active (A)- to deactive (D)-form after H-R. - Abstract: Although aquatic organisms face multiple environmental stressors that may interact to alter adverse outcomes, our knowledge of stressor–stressor interaction on cellular function is limited. We investigated the combined effects of cadmium (Cd), hypoxia-reoxygenation (H-R) and temperature on mitochondrial function. Liver mitochondria from juvenile rainbow trout were exposed to Cd (0–20 μM) and H-R (0 and 5 min) at 5, 13 and 25 °C followed by measurements of mitochondrial Cd load, volume, complex I active (A) ↔ deactive (D) transition, membrane potential, ROS release and ultrastructural changes. At high temperature Cd exacerbated H-R-imposed reduction of maximal complex I (CI) respiration whereas at low temperature 5 and 10 μM stimulated maximal CI respiration post H-R. The basal respiration showed a biphasic response at high temperatures with low Cd concentrations reducing the stimulatory effect of H-R and high concentrations enhancing this effect. At low temperature Cd monotonically enhanced H-R-induced stimulation of basal respiration. Cd and H-R reduced both the P/O ratio and the RCR at all 3 temperatures. Temperature rise alone increased mitochondrial Cd load and toxicity, but combined H-R and temperature exposure reduced mitochondrial Cd load but surprisingly exacerbated the mitochondrial dysfunction. Mitochondrial dysfunction induced by H-R was associated with swelling of the organelle and blocking of conversion of CI D to A form. However, low amounts of Cd protected against H

  15. COMPARISON OF THE QUALITY OF RNA ISOLATED FROM THE RAINBOW TROUT (Oncorhynchus mykiss TISSUE IN FOUR DIFFERENT WAYS

    Directory of Open Access Journals (Sweden)

    Irena Vardić

    2004-03-01

    Full Text Available Rapid and accurate diagnostic procedures for identification of reared fish diseases are important in order to reduce serious losses in relation of diseases outbrakes. Therefore, molecular biology methods are required for such types of investigations. First level in these experiments are DNA or RNA isolation. Tissue preparation for isolation of RNA, which is used in further RT-PCR (reverse transcription-polymerise chain reaction analysis is the key step on which is the whole process of analysis dependent. Our goal was to compare quality and integrity of RNA isolated from the rainbow trout tissue, which was prepared in four different ways: fresh tissue, frozen tissue, in formalin-fixed, paraffin embedded tissue as well as in methacarn-fixed, paraffin embedded tissue. Isolated RNA was analyzed in gel electrophoresis on non-denaturated, 1% agarose gel. Quality and integrity of RNA was proved by RT-PCR reaction with primers for ß-actin gene. Additional, prepared tissue was tested on presence of two fish viruses: viral haemorrhagic septicaemia (VHS virus and infectious haematopoietic necrosis (IHN virus in RT-PCR reaction with primers specific for these viruses. RNA isolated from fresh and frozen tissue was of high quality, integrity and quantity. RNA isolated from in methacarn-fixed, paraffin embedded tissue was quite disintegrated, but in RT-PCR with primers for ß-actin gave expected products. These products were absent after RT-PCR reaction with in formallin-fixed, paraffin-embedded tissue. That agrees with the facts from the literature about very agressive affect of formalin as a fixative on RNA in tissue. Inspected fish were not infected with VHS and IHN viruses and that was in agreement with results of clinical examination and pathological analysis. According to our knowledge, this is the first successful RNA isolation from in methacarn-fixed, paraffin embedded fish tissue. Isolated RNA can be used for further analysis in RT-PCR reaction. This

  16. 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.

  17. OCCURRENCE OF INFECTIOUS PANCREATIC NECROSIS VIRUS (IPNV) IN FARMED RAINBOW TROUT (ONCHORHYNCHUS MYKISS) IN KOSOVO

    OpenAIRE

    Agim Rexhepi; Kristaq Berxholli; Peter Scheinert; Afrim Hamidi; Kurtesh Sherifi

    2013-01-01

    This article describes the research carried out for the detection of viruses responsible for VHS, IHN and IPN diseases in farmed rainbow trout (Oncorhynchus mykiss) in Kosovo for the three-year period between 2006 and 2008. Losses are often reported in trout fingerlings, but no virus has ever been isolated in the rainbow trout in Kosovo. A research project was carried out to determine the occurrence of VHSV, IHNV & IPNV from the samples of fish tissue and ovarian fluids from mature broodf...

  18. Interactive effects of naphthalene treatment and the onset of vitellogenesis on energy metabolism in liver and gonad, and plasma steroid hormones of rainbow trout Oncorhynchus mykiss.

    Science.gov (United States)

    Tintos, Adrián; Gesto, Manuel; Alvarez, Rosa; Míguez, Jesús M; Soengas, José L

    2006-10-01

    The purpose of the study was to assess in female fish the possible interaction between treatment with a polycyclic aromatic hydrocarbon (PAH) like naphthalene and the onset of vitellogenesis. In a first experiment, female rainbow trout (Oncorhynchus mykiss) at stages 2-3 (previtellogenesis) or 4 (early vitellogenesis) were intraperitoneally injected (2 microl g(-1)) with vegetable oil alone (control) or containing naphthalene (50 mg kg(-1)) to be sampled 3 h later. A second experiment was similarly designed but using fish intraperitoneally implanted (10 microl g(-1)) with slow-release coconut oil implants alone (control) or containing 50 mg naphthalene kg(-1) body mass that were sampled 3 days after injection. On each sampling time, plasma levels of cortisol and 17beta-estradiol, and several metabolic parameters in plasma, liver and gonad were assessed. In controls, early vitellogenic fish compared with previtellogenic fish displayed changes that in some cases are confirmatory of previous studies whereas in other cases provide new information in plasma (increased amino acid levels), liver (decreased capacity for exporting glucose and reduced amino acid levels) and gonad (decreased amino acid levels). Naphthalene treatment produced in previtellogenic fish decreased 17beta-estradiol levels in plasma, increased plasma glucose or decreased liver gluconeogenic capacity whereas no major effects were noticed on parameters involved in lipid, amino acid and lactate metabolism. Differential effects of naphthalene treatment were noticed in early vitellogenic fish such as decreased 17beta-estradiol and glucose levels in plasma, increased hexokinase and glucokinase and lack of changes in fructose 1,6-bisphosphatase activities in liver, and a lower decrease of amino acid levels in gonad. Those alterations produced by naphthalene treatment resulted in a decreased capacity for covering the energy demand of vitellogenesis in liver and gonad that could contribute to a delay and

  19. Plasma 11-deoxycorticosterone (DOC) and mineralocorticoid receptor testicular expression during rainbow trout Oncorhynchus mykiss spermiation: implication with 17alpha, 20beta-dihydroxyprogesterone on the milt fluidity?

    Science.gov (United States)

    Milla, Sylvain; Terrien, Xavier; Sturm, Armin; Ibrahim, Fidaa; Giton, Franck; Fiet, Jean; Prunet, Patrick; Le Gac, Florence

    2008-05-19

    In rainbow trout (Oncorhynchus mykiss), the endocrine control of spermiation is not fully understood. Besides 11ketotestosterone (11KT) and 17alpha, 20beta-dihydroxyprogesterone (MIS), the potential physiological ligand of the mineralocorticoid receptor (MR) 11-deoxycorticosterone (DOC), is a credible candidate in O. mykiss spermiation regulation as spermiation is accompanied with changes in aqueous and ionic flows. In this study, we investigated potential roles of DOC during spermiation 1) by describing changes in blood plasma DOC level, MR mRNA abundance during the reproductive cycle and MR localization in the reproductive tract 2) by investigating and comparing the effects of DOC (10 mg/kg) and MIS (5 mg/kg) supplementations on sperm parameters 3) by measuring the in vitro effect of DOC on testis MIS production. The plasma concentration of DOC increased rapidly at the end of the reproductive cycle to reach levels that were 10-50 fold higher in mature males than in immature fish. MR mRNA relative abundance was lower in maturing testes when compared to immature testes, but increased rapidly during the spermiation period, immediately after the plasma rise in DOC. At this stage, immunohistochemistry localized MR protein to cells situated at the periphery of the seminiferous tubules and in the efferent ducts. Neither DOC nor MIS had significant effects on the mean sperm volume, although MIS treatment significantly increased the percentage of males producing milt. However, a significant reduction in the spermatocrit was observed when DOC and MIS were administrated together. Finally, we detected an inhibitory effect of DOC on testis MIS production in vitro. These results are in agreement with potential roles of DOC and MR during spermiation and support the hypothesis that DOC and MIS mechanisms of action are linked during this reproductive stage, maybe controlling milt fluidity. They also confirm that in O. mykiss MIS is involved in spermiation induction.

  20. Immune gene expression profiling of Proliferative Kidney Disease in rainbow trout Oncorhynchus mykiss reveals a dominance of anti-inflammatory, antibody and T helper cell-like activities.

    Science.gov (United States)

    Gorgoglione, Bartolomeo; Wang, Tiehui; Secombes, Christopher J; Holland, Jason W

    2013-07-16

    The myxozoan Tetracapsuloides bryosalmonae is the causative agent of Proliferative Kidney Disease (PKD) targeting primarily the kidney of infected fish where it causes a chronic lymphoid immunopathology. Although known to be associated with suppression of some cellular aspects of innate immunity and a prominent lymphocytic hyperplasia, there remains a considerable knowledge gap in our understanding of the underlying immune mechanisms driving PKD pathogenesis. To provide further insights, the expression profiles of a panel of innate/inflammatory and adaptive immune molecules were examined in rainbow trout Oncorhynchus mykiss following a natural exposure to the parasite. Relative to controls, fish with early to advanced stages of kidney pathology exhibited up-regulation of the inflammatory cytokines interleukin (IL)-6 and IL-11, although remaining refractory towards genes indicative of macrophage activity. Antimicrobial peptides (AMPs) and anti-inflammatory markers, including cathelicidin (CATH) and IL-10 were markedly up-regulated during clinical disease. Up-regulation of adaptive immune molecules, including cell markers and antibody genes reflect the lymphocytic dominance of this disease and the likely importance of lymphocyte subsets in PKD pathogenesis. Up-regulation of T helper (TH) cell-like response genes and transcription factors implies that T. bryosalmonae may elicit a complex interplay between TH cell subsets. This work, for the first time in the study of fish-myxozoan interactions, suggests that PKD pathogenesis is shaped by an anti-inflammatory phenotype, a profound B cell/antibody response and dysregulated TH cell-like activities. A better understanding of the functional roles of fish immune cells and molecules in PKD pathogenesis may facilitate future development of control measures against this disease.