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Sample records for rainbow trout influence

  1. 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 (...

  2. 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

  3. Rainbow trout movement behavior and habitat occupancy are influenced by sex and Pacific salmon presence in an Alaska river system

    Science.gov (United States)

    Fraley, Kevin M.; Falke, Jeffrey A.; McPhee, Megan V.; Prakash, Anupma

    2018-01-01

    We used spatially continuous field-measured and remotely-sensed aquatic habitat characteristics paired with weekly ground-based telemetry tracking and snorkel surveys to describe movements and habitat occupancy of adult rainbow trout (N = 82) in a runoff-fed, salmon-influenced southcentral Alaska river system. We found that during the ice-free feeding season (June through September) rainbow trout occurrence was associated more with fine-scale (channel unit) characteristics relative to coarse-scale (stream reach) variables. The presence of Pacific salmon (which provide an important seasonal food subsidy), and habitat size were particularly useful predictors. Weekly movement distance differed between pre- and post- spawning salmon arrival, but did not vary by sex. Habitat quality, season, and the arrival of spawning salmon influenced the likelihood of rainbow trout movement, and fish moved farther to seek out higher quality habitats. Because rainbow trout respond to habitat factors at multiple scales and seek out salmon-derived subsidies, it will be important to take a multiscale approach in protecting trout and salmon populations and managing the associated fisheries.

  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. 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...

  6. 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

  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. 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.

  9. Farming of Freshwater Rainbow Trout in Denmark

    DEFF Research Database (Denmark)

    Jokumsen, Alfred; Svendsen, Lars Moeslund

    Textbook on Farming of Freshwater Rainbow Trout in Denmark. Danish edition with the title: Opdræt af regnbueørred i Danmark......Textbook on Farming of Freshwater Rainbow Trout in Denmark. Danish edition with the title: Opdræt af regnbueørred i Danmark...

  10. 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.

  11. 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.

  12. Influence of dissolved oxygen concentration on the toxicity of potassium cyanide to rainbow trout. [Salmo gairdneri

    Energy Technology Data Exchange (ETDEWEB)

    Downing, K M

    1954-01-01

    The present work was undertaken to see if similar results were obtained when fish were tested in a continuous flow of water in which the concentrations of oxygen and cyanide were kept constant. Periods of survival were measured this way to minimize distortion of results by accumulation of metabolic waste, depletion of oxygen or depletion of poison. Results are summarized as follows: rainbow trout survival in potassium cyanide increased with increase in dissolved oxygen; increase in survival times did not decline as oxygen saturation was approached; and medium survival times of 3.3 minutes or less were normally distributed while those of greater than 13 minutes were log normally distributed. 6 references, 1 figure.

  13. Influence of organic diets and probiotics on an experimental Flavobacterium psychrophilum infection in rainbow trout fry

    DEFF Research Database (Denmark)

    Madsen, Lone; Ingerslev, Hans-Christian; Boye, Mette

    2012-01-01

    following exposure to pathogenic microorganisms. The aim of the Danish project OPTIFISH is to optimize growth and survival for organic cultured rainbow trout. OPTIFISH investigates how organic vs. non-organic diet types as well as diets with or without probiotics affect the intestine, the intestinal...... of fry to pathogens, e.g. F .psychrophilum. In the current experiment four diet types were tested on fry, a conventional type (Inicio®, BioMar A/S) with and without probiotics, as well as an organic type with and without probiotic. Bactocell® (Lallemand) was used as the probiotic. Studies were done...... been fed diets that were organic or conventional nor if the feed had been added probiotic. No significance in mortalities was seen between the diet groups. The bacteriological examinations showed that the bacterium had entered the fish, as it was found in inner organs in one fourth of the sampled fish...

  14. 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.

  15. Influence of Dietary Selenium Species on Selenoamino Acid Levels in Rainbow Trout.

    Science.gov (United States)

    Godin, Simon; Fontagné-Dicharry, Stéphanie; Bueno, Maïté; Tacon, Philippe; Prabhu, Philip Antony Jesu; Kaushik, Sachi; Médale, Françoise; Bouyssiere, Brice

    2015-07-22

    Two forms of selenium (Se) supplementation of fish feeds were compared in two different basal diets. A 12-week feeding trial was performed with rainbow trout fry using either a plant-based or a fish meal-based diet. Se yeast and selenite were used for Se supplementation. Total Se and Se speciation were determined in both diets and whole body of trout fry using inductively coupled plasma mass spectrometry (ICP MS) and high-performance liquid chromatography (HPLC). The two selenoamino acids, selenomethionine (SeMet) and selenocysteine (SeCys), were determined in whole body of fry after enzymatic digestion using protease type XIV with a prior derivatization step in the case of SeCys. The plant-based basal diet was found to have a much lower total Se than the fish meal-based basal diet with concentrations of 496 and 1222 μg(Se) kg(-1), respectively. Dietary Se yeast had a higher ability to raise whole body Se compared to selenite. SeMet concentration in the fry was increased only in the case of Se yeast supplementation, whereas SeCys levels were similar at the end of the feeding trial for both Se supplemented forms. The results show that the fate of dietary Se in fry is highly dependent on the form brought through supplementation and that a plant-based diet clearly benefits from Se supplementation.

  16. 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

  17. 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...

  18. 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.

  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. 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.

  1. 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.

  2. Bath vaccination of rainbow trout against yersiniosis

    DEFF Research Database (Denmark)

    Raida, Martin Kristian; Buchmann, Kurt

    2007-01-01

    disease (ERM), was investigated at 5, 15 and 25° C. Rainbow trout fry were kept at controlled temperatures for two month before they were immersed in a commercial Yersinia ruckeri O1 bacterin for 10 minutes. Control groups were sham vaccinated using pure water. Fish were challenged with Yersinia ruckeri O...

  3. 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- ...

  4. Impacts of Northern Pike on stocked Rainbow Trout in Pactola Reservoir, South Dakota

    Science.gov (United States)

    Scheibel, Natalie C.; Dembkowski, Daniel J.; Davis, Jacob L.; Chipps, Steven R.

    2016-01-01

    Establishment of nonnative Northern Pike Esox lucius in Pactola Reservoir, South Dakota, has prompted concern among biologists about the influence of this species on the lake’s intensively managed salmonid fisheries. Ancedotal information suggests that catch rates of Rainbow Trout Oncorhynchus mykiss have declined while mean size and abundance of Northern Pike has increased, although quantitative information on diet and growth of the Northern Pike population is lacking. To address potential interactions between Northern Pike and Rainbow Trout, we assessed size-dependent predation by Northern Pike on Rainbow Trout and determined the relative energetic contribution of stocked Rainbow Trout to Northern Pike growth using bioenergetics modeling. Stable isotopes combined with traditional diet analyses revealed that smaller Northern Pike (Trout contributed less than 10% to their annual energy consumption. In contrast, larger Northern Pike (≥600 mm TL) consumed primarily Rainbow Trout, which accounted for 56% of their annual energy consumption. Combining estimates of Northern Pike predation with production costs of catchable-size Rainbow Trout revealed that annual economic losses ranged from US$15,259 to $24,801 per year. Over its lifespan, an age-10 Northern Pike was estimated to consume ~117 Rainbow Trout worth approximately $340. Thus, Northern Pike predation substantially influences salmonid management initiatives and is likely a primary factor contributing to reduced Rainbow Trout abundance and return to anglers in Pactola Reservoir. Strategies for reducing Northern Pike predation on Rainbow Trout include increasing the size of stocked fish or altering the timing and spatial distribution of stocking events.

  5. 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

  6. Utilization of dietary urea in rainbow trout.

    Science.gov (United States)

    Kaushik, S J; Dabrowski, K R; Dabrowska, H; Olah, E; Luquet, P

    1983-01-01

    Experiments were conducted to examine the potential utilization of dietary urea by rainbow trout. A control diet and two diets supplemented with 1 and 3% of urea were fed to fish. Postprandial levels of urea and ammonia in blood plasma, and postprandial excretion of these metabolites were followed during 24 h. Apparent digestibility of urea in rainbow trout was very high (greater than 98%). Maximum values of urea levels in plasma were reached 6 h (32.3 +/- 10.2 micrograms/ml) after a meal in the control fish and respectively 6 h (83.4 +/- 18.4 micrograms/ml) and 8 h (250.3 +/- 96.1 micrograms/ml) after a meal in trout fed 1 and 3% urea diets. Peaks of urea excretion rates appeared 7-9 h after meal, coinciding with the highest circulating urea concentration. Total daily urea excretion amounted to 5.53, 10.43 and 33.80 mg urea N/100 mg N intake in trout fed the control, 1 and 3% urea diets, respectively. It is concluded that the dietary urea is readily absorbed in the digestive tract of trout but is totally excreted thus leading to no beneficial effect on nitrogen balance. This excretion of urea also takes place passively without any increase in energy demands.

  7. 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...

  8. Fish life histories, wildfire, and resilience - A case study of rainbow trout in the Boise River, Idaho

    Science.gov (United States)

    Amanda E. Rosenberger; Jason B. Dunham; Helen Neville

    2012-01-01

    In this short piece we address the question of how aquatic ecosystems and species can change in response to disturbances, such as those related to the influence of wildfire on stream ecosystems. Our focal species is rainbow trout (Oncorhynchus mykiss) in the Boise River, Idaho. Rainbow trout in this system have persisted in the face of widespread and often severe...

  9. Correlation between Leukocyte Numbers and Body Size of Rainbow Trout

    DEFF Research Database (Denmark)

    Mohammad, Rezkar Jaafar; Otani, Maki; Kania, Per Walter

    2016-01-01

    wild and cultured fish and we show that the size of the leukocyte population increases exponentially with body size of rainbow trout. Four groups (5 fish/group) of naive rainbow trout (Oncorhynchus mykiss) with a mean body weight of 2 - 4 g (group I), 4 - 6 g (group II), 25 - 30 g (group III), and 650...... towards an antigen to be initiated even in fry. The number of leukocytes in individual fish at different developmental stages is likely to influence the capacity of the fish to respond simultaneously to several antigens (pathogens and vaccine components). This parameter may therefore be crucial for both...... - 780 g (group IV) were investigated. The number of lymphocytes was generally higher in head kidney compared to blood and spleen but they dominated in all samples (blood, head kidney and spleen) and their numbers increased exponentially with fish size. Percentages of lymphocytes in relation...

  10. Immunity to VHS virus in rainbow trout

    DEFF Research Database (Denmark)

    Lorenzen, Niels; Olesen, Niels Jørgen; Koch, C.

    1999-01-01

    Viral hemorrhagic septicemia virus (VHSV) is the rhabdovirus that causes most disease problems in farmed rainbow trout in Europe. Survivors of infection are usually immune to reinfection but as with other fish viruses, development of a modern recombinant vaccine has been complicated by the limited...... knowledge of the immune mechanisms and antigens involved in induction of immunity. Neutralizing and protective monoclonal antibodies recognize the envelope glycoprotein (G protein) which is the only viral protein known to be present on the surface of the virus particle. Immunoblotting analyses...... with monoclonal antibodies as well as with sera from immunized trout have indicated that protein conformation plays an important role in neutralization epitopes. The virus neutralizing activity often found in sera from convalescent trout is highly dependent on a poorly defined complementing activity in normal...

  11. 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....

  12. Movement of resident rainbow trout transplanted below a barrier to anadromy

    Science.gov (United States)

    Wilzbach, Margaret A.; Ashenfelter, Mark J.; Ricker, Seth J.

    2012-01-01

    We tracked the movement of resident coastal rainbow trout Oncorhynchus mykiss irideus that were experimentally transplanted below a migration barrier in a northern California stream. In 2005 and 2006, age-1 and older rainbow trout were captured above a 5-m-high waterfall in Freshwater Creek and individually marked with passive integrated transponder tags. Otolith microchemistry confirmed that the above-barrier trout were the progeny of resident rather than anadromous parents, and genetic analysis indicated that the rainbow trout were introgressed with cutthroat trout O. clarkii. At each of three sampling events, half of the tagged individuals (n = 22 and 43 trout in 2005 and 2006, respectively) were released 5 km downstream from the waterfall (approximately 10 km upstream from tidewater), and an equal number of tagged individuals were released above the barrier. Tagged individuals were subsequently relocated with stationary and mobile antennae or recaptured in downstream migrant traps, or both, until tracking ceased in October 2007. Most transplanted individuals remained within a few hundred meters of their release location. Three individuals, including one rainbow trout released above the waterfall, were last detected in the tidally influenced lower creek. Two additional tagged individuals released above the barrier were found alive in below-barrier reaches and had presumably washed over the falls. Two of seven tagged rainbow trout captured in downstream migrant traps had smolted and one was a presmolt. The smoltification of at least some individuals, coupled with above-barrier "leakage" of fish downstream, suggests that above-barrier resident trout have the potential to exhibit migratory behavior and to enter breeding populations of steelhead (anadromous rainbow trout) within the basin.

  13. Rainbow Trout Distribution, Pacific Northwest (updated March, 2006)

    Data.gov (United States)

    Pacific States Marine Fisheries Commission — This dataset is a record of fish distribution and activity for RAINBOW TROUT contained in the StreamNet database. This feature class was created based on linear...

  14. 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.

  15. 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

  16. Prevalence and location of Listeria monocytogenes in farmed rainbow trout.

    Science.gov (United States)

    Miettinen, Hanna; Wirtanen, Gun

    2005-10-15

    A total of 510 rainbow trout originating from fish farms in lakes and sea areas around Finland were studied for the presence of Listeria monocytogenes. Samples were studied as pools from five fish. Gill, viscera, and skin from the pooled samples were analysed separately. The individual samples were analysed later if the pooled sample was found to be Listeria positive. The prevalence of Listeria spp. and L. monocytogenes in pooled unprocessed fresh rainbow trout was on average 35.0% and 14.6%, respectively. On the other hand, the prevalence of Listeria spp. and L. monocytogenes in individual thawed fish was found to be 14.3% and 8.8%, respectively. These numbers tend to overestimate and underestimate the real situation because not all fish in pooled samples were necessarily contaminated and in some of the Listeria positive pooled samples all individual samples turned out to be Listeria free. The prevalence of L. monocytogenes varied greatly between different fish farms from zero to 100% in pooled samples and from zero to 75% according to individually studied fish samples. Some indications of the influence of weather conditions and seasonal variations that strongly affected the Listeria contamination of fish were also noticed. The location of Listeria spp. and L. monocytogenes in different parts of the fish differed with statistical significance in rainbow trout. Up to 95.6% of the L. monocytogenes and 84.5% of Listeria spp. positive samples were gill samples. Only 4.4% (2/45) of the L. monocytogenes positive samples were obtained from skin or viscera. Closer study at one fish farm revealed that there was only one L. monocytogenes ribotype present in the contaminated fish, although water and surfaces were heavily contaminated with six other L. monocytogenes ribotypes.

  17. 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.

  18. The Influence of Infective Dose on the Virulence of a Generalist Pathogen in Rainbow Trout (Oncorhynchus mykiss and Zebra Fish (Danio rerio.

    Directory of Open Access Journals (Sweden)

    Hanna Kinnula

    Full Text Available Pathogen density and genetic diversity fluctuate in the outside-host environment during and between epidemics, affecting disease emergence and the severity and probability of infections. Although the importance of these factors for pathogen virulence and infection probability has been acknowledged, their interactive effects are not well understood. We studied how an infective dose in an environmentally transmitted opportunistic fish pathogen, Flavobacterium columnare, affects its virulence both in rainbow trout, which are frequently infected at fish farms, and in zebra fish, a host that is not naturally infected by F. columnare. We used previously isolated strains of confirmed high and low virulence in a single infection and in a co-infection. Infection success (measured as host morbidity correlated positively with dose when the hosts were exposed to the high-virulence strain, but no response for the dose increase was found when the hosts were exposed to the low-virulence strain. Interestingly, the co-infection resulted in poorer infection success than the single infection with the high-virulence strain. The rainbow trout were more susceptible to the infection than the zebra fish but, in both species, the effects of the doses and the strains were qualitatively similar. We suggest that as an increase in dose can lead to increased host morbidity, both the interstrain interactions and differences in infectivity in different hosts may influence the severity and consequently the evolution of disease. Our results also confirm that the zebra fish is a good laboratory model to study F. columnare infection.

  19. 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...

  20. 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.

  1. NITRO MUSK ADDUCTS OF RAINBOW TROUT ...

    Science.gov (United States)

    Rainbow trout and other fish species can serve as 'sentinel' species for the assessment of ecological status and the presence of certain environmental contaminants. As such they act as bioindicators of exposure. Here we present seminal data regarding dose-response and toxicokinetics of trout hemoglobin adduct formation from exposure to nitro musks that are frequently used as fragrance ingredients in formulations of personal care products. Hemoglobin adducts serve as biomarkers of exposure of the sentinel species as we have shown in previous studies of hemoglobin adducts formed in trout and environmental carp exposed to musk xylene (MX) and musk ketone (MK). Gas chromatography-electron capture negative ion chemical ionization-mass spectrometry (GC-NICI-MS) employing selected ion monitoring is used to measure 4-amino-MX (4-AMX), 2-amino-MX (2-AMX), and 2-amino-MK (2-AMK) released by alkaline hydrolysis from the sulfinamide adducts of hemoglobin. Dose-response and toxicokinetics were investigated using this sensitive method for analysis of these metabolites. In the dose-response investigation, the concentrations of 4-AMX and 2-2AMX are observed to pass through a maximum at 0.10 mg/g. In the case of 2-AMK, the adduct concentration is almost the same at dosages in the range of 0.030 to 0.10 mg/g. For toxicokinetics, the concentration of the metabolites in the Hb reaches a maximum in the 3-day sample after administration of MX or MK. Further elimination of the metabo

  2. Influence of essential oils in diet and life-stage on gut microbiota and fillet quality of rainbow trout (Oncorhynchus mykiss).

    Science.gov (United States)

    Ceppa, Florencia; Faccenda, Filippo; De Filippo, Carlotta; Albanese, Davide; Pindo, Massimo; Martelli, Roberta; Marconi, Paola; Lunelli, Fernando; Fava, Francesca; Parisi, Giuliana

    2018-05-01

    Developing fish farming to meet the demands of food security and sustainability in the 21st century will require new farming systems and improved feeds. Diet and microbe interactions in the gut is an important variable with the potential to make a significant impact on future fish farming diets and production systems. It was monitored the gut microbiota of farmed rainbow trout using 16S rRNA profiling over 51 weeks during standard rearing conditions and feeding diet with supplementation of an essential oils (MixOil) mixture from plants (at a concentration in diet of 200 mg/kg). Gut microbiota 16S rRNA profiling indicated that the fish gut was dominated by Actinobacteria, Proteobacteria, Bacteroidetes and Firmicutes. Although the dietary supplementation with MixOil had no impact on either the composition or architecture of gut microbiota, significant changes in alpha and beta diversity and relative abundance of groups of gut bacteria were evident during growth stages on test feeds, especially upon prolonged growth on finishing feed. Fish fillet quality to guarantee palatability and safety for human consumption was also evaluated. Significant differences within the gut microbiota of juvenile and adult trout under the same rearing conditions were observed, The addition of essential oil blend affected some physicochemical characteristics of trout fillets, including their resistance to oxidative damage and their weight loss (as liquid loss and water holding capacity) during the first period of storage, that are two important parameters related to product shelf life and susceptibility to spoilage. The results highlighted the need for further studies concern dietary microbiome modulation at different life stages and its influence on animal health, growth performance and final product quality.

  3. Erosion of interspecific reproductive barriers resulting from hatchery supplementation of rainbow trout sympatric with cutthroat trout.

    Science.gov (United States)

    Docker, Margaret F; Dale, Angie; Heath, Daniel D

    2003-12-01

    The frequency of hybridization between cutthroat (Onchorhynchus clarki clarki) and rainbow (O. mykiss irideus) trout from coastal habitats in British Columbia, Canada, was examined in seven populations where the two species are sympatric with no history of rainbow trout stocking and compared with areas where native rainbow trout populations have been supplemented with hatchery fish (three populations). Four nuclear markers were used to identify each species and interspecific hybrids and one mitochondrial marker showed the direction of gene exchange between species. The frequency of hybrids was significantly higher (Fisher exact test, P < 0.001) in river systems where hatchery rainbow trout have been introduced (50.6% hybrids) than in populations where the two species naturally co-occur without supplementation (9.9% hybrids).

  4. Patterns of hybridization of nonnative cutthroat trout and hatchery rainbow trout with native redband trout in the Boise River, Idaho

    Science.gov (United States)

    Neville, Helen M.; Dunham, Jason B.

    2011-01-01

    Hybridization is one of the greatest threats to native fishes. Threats from hybridization are particularly important for native trout species as stocking of nonnative trout has been widespread within the ranges of native species, thus increasing the potential for hybridization. While many studies have documented hybridization between native cutthroat trout Oncorhynchus clarkii and nonnative rainbow trout O. mykiss, fewer have focused on this issue in native rainbow trout despite widespread threats from introductions of both nonnative cutthroat trout and hatchery rainbow trout. Here, we describe the current genetic (i.e., hybridization) status of native redband trout O. mykiss gairdneri populations in the upper Boise River, Idaho. Interspecific hybridization was widespread (detected at 14 of the 41 sampled locations), but high levels of hybridization between nonnative cutthroat trout and redband trout were detected in only a few streams. Intraspecific hybridization was considerably more widespread (almost 40% of sampled locations), and several local populations of native redband trout have been almost completely replaced with hatchery coastal rainbow trout O. mykiss irideus; other populations exist as hybrid swarms, some are in the process of being actively invaded, and some are maintaining genetic characteristics of native populations. The persistence of some redband trout populations with high genetic integrity provides some opportunity to conserve native genomes, but our findings also highlight the complex decisions facing managers today. Effective management strategies in this system may include analysis of the specific attributes of each site and population to evaluate the relative risks posed by isolation versus maintaining connectivity, identifying potential sites for control or eradication of nonnative trout, and long-term monitoring of the genetic integrity of remaining redband trout populations to track changes in their status.

  5. Interactions of waterborne and dietary cadmium on the expression of calcium transporters in the gills of rainbow trout: Influence of dietary calcium supplementation

    International Nuclear Information System (INIS)

    Galvez, Fernando; Franklin, Natasha M.; Tuttle, Ryan B.; Wood, Chris M.

    2007-01-01

    Recent studies have shown that dietary Ca 2+ supplementation strongly inhibits uptake of Ca 2+ and Cd at the fish gill. To better understand the influence of dietary Ca 2+ on branchial Ca 2+ transport, we examined the expression of two trout gill calcium transporters during waterborne and dietary Cd exposure, at two different levels of dietary Ca 2+ . Quantitative polymerase chain reaction (PCR) was used to monitor epithelial calcium channel (ECaC) and sodium-calcium exchange (NCX) mRNA levels following 7-28 days of exposure to these treatments. In brief, juvenile rainbow trout (Oncorhynchus mykiss) were exposed to control, 3 μg/L waterborne Cd, 500 mg/kg dietary Cd, or a combined 3 μg/L waterborne plus 500 mg/kg dietary Cd exposure, supplemented with either 20 mg/g or 60 mg/g dietary calcium (Ca 2+ ). Two-way analysis of variance was used to discern the main effects of Cd exposure and dietary Ca 2+ supplementation on ECaC and NCX mRNA levels. We found that dietary Ca 2+ supplementation decreased significantly ECaC mRNA expression on days 14 and 21. In comparison, NCX mRNA levels were not influenced by dietary Ca 2+ supplementation, but rather were significantly inhibited in the combined waterborne and dietary Cd exposure on day 7 alone. Statistical analysis found no interactive effects between Cd exposure and dietary Ca 2+ exposure at any time point, except for day 28.This study provides evidence of the importance of nutritional status on the transcriptional regulation of ion transport at the fish gill. We discuss the importance of diet and nutritional status to the development of new regulatory approaches, such as the biotic ligand model, which currently do not account for the significance of diet on metal bioavailability in aquatic organisms

  6. Immunity to rhabdoviruses in rainbow trout: the antibody response

    DEFF Research Database (Denmark)

    Lorenzen, Niels; Lapatra, S.E.

    1999-01-01

    to their occasional detrimental effect on rainbow trout farming. Research efforts have been focused on understanding the mechanisms involved in protective immunity. Several specific and nonspecific cellular and humoral parameters are believed to be involved, but only the antibody response has been characterised......, have demonstrated that rainbow trout can produce specific and highly functional antibodies that are able to neutralise virus pathogenicity in vitro as well as in vivo. The apparently more restricted antibody response to IHNV and VHSV antigens in fish compared to mammals could possibly be explained...... aspects of antibody response and antibody reactivity with IHNV and VHSV antigens....

  7. ERM booster vaccination of Rainbow trout using diluted bacterin

    DEFF Research Database (Denmark)

    Schmidt, Jacob Günther; Henriksen, Niels H.; Buchmann, Kurt

    2016-01-01

    under laboratory conditions extend the protection period. The present field study investigated the applicability of the method under practical farming conditions (freshwater earth ponds supplied by stream water). Primary immersion vaccination of trout (3–4 g) for 30 s in Y. ruckeri bacterin (diluted 1......Enteric Red Mouth Disease ERM caused by Yersinia ruckeri infection is associated with morbidity and mortality in salmonid farming but immersion vaccination of fry may confer some protection for a number of months. Revaccination of rainbow trout, even by use of diluted ERM immersion vaccine, can......:10) in April 2015 was followed 3 months later (July 2015) by 1 h bathing of rainbow trout in bacterin (diluted 1:650 or 1:1700) in order to evaluate if this time saving vaccination methodology can improve immunity and protection. Trout were subjected in farms to natural Y. ruckeri exposure in June and July...

  8. Cod and rainbow trout as freeze-chilled meal elements

    DEFF Research Database (Denmark)

    Jensen, Louise Helene Søgaard; Nielsen, Jette; Jørgensen, Bo

    2010-01-01

    Meal elements' are elements of a meal, e.g. portions of pre-fried meat, sauces, frozen fish or pre-processed vegetables typically prepared industrially. The meal elements are distributed to professional satellite kitchens, where the staff can combine them into complete meals. Freeze......-chilling is a process consisting of freezing and frozen storage followed by thawing and chilled storage. Combining the two would enable the manufacturer to produce large quantities of frozen meal elements to be released into the chill chain according to demand. We have studied the influence of freeze...... days of chilled storage, and the corresponding time for rainbow trout was 10 days. After this period the sensory quality decreased and chemical indicators of spoilage were seen to increase. CONCLUSION: The consistent quality during storage and the high-quality shelf life are practically applicable...

  9. 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

  10. 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.

  11. 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.

  12. 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...

  13. 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...

  14. 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

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

    Science.gov (United States)

    Johnson, James H.; McKenna, James E.

    2015-01-01

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

  16. 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.

  17. 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

  18. Intracellular diffusion restrictions in isolated cardiomyocytes from rainbow trout

    Directory of Open Access Journals (Sweden)

    Birkedal Rikke

    2009-12-01

    Full Text Available Abstract Background Restriction of intracellular diffusion of adenine nucleotides has been studied intensively on adult rat cardiomyocytes. However, their cause and role in vivo is still uncertain. Intracellular membrane structures have been suggested to play a role. We therefore chose to study cardiomyocytes from rainbow trout (Oncorhynchus mykiss, which are thinner and have fewer intracellular membrane structures than adult rat cardiomyocytes. Previous studies suggest that trout permeabilized cardiac fibers also have diffusion restrictions. However, results from fibers may be affected by incomplete separation of the cells. This is avoided when studying permeabilized, isolated cardiomyocytes. The aim of this study was to verify the existence of diffusion restrictions in trout cardiomyocytes by comparing ADP-kinetics of mitochondrial respiration in permeabilized fibers, permeabilized cardiomyocytes and isolated mitochondria from rainbow trout heart. Experiments were performed at 10, 15 and 20°C in the absence and presence of creatine. Results Trout cardiomyocytes hypercontracted in the solutions used for mammalian cardiomyocytes. We developed a new solution in which they retained their shape and showed stable steady state respiration rates throughout an experiment. The apparent ADP-affinity of permeabilized cardiomyocytes was different from that of fibers. It was higher, independent of temperature and not increased by creatine. However, it was still about ten times lower than in isolated mitochondria. Conclusions The differences between fibers and cardiomyocytes suggest that results from trout heart fibers were affected by incomplete separation of the cells. However, the lower ADP-affinity of cardiomyocytes compared to isolated mitochondria indicate that intracellular diffusion restrictions are still present in trout cardiomyocytes despite their lower density of intracellular membrane structures. The lack of a creatine effect indicates that

  19. 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.

  20. 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.

  1. Interactions of waterborne and dietary cadmium on the expression of calcium transporters in the gills of rainbow trout: Influence of dietary calcium supplementation

    Energy Technology Data Exchange (ETDEWEB)

    Galvez, Fernando [Department of Biological Sciences, Louisiana State University, Baton Rouge, LA 70803 (United States); Department of Biology, McMaster University, Hamilton, Ontario, L8S 4K1 (Canada)], E-mail: galvezf@lsu.edu; Franklin, Natasha M. [Department of Biology, McMaster University, Hamilton, Ontario, L8S 4K1 (Canada); Tuttle, Ryan B. [Department of Biological Sciences, Louisiana State University, Baton Rouge, LA 70803 (United States); Wood, Chris M. [Department of Biology, McMaster University, Hamilton, Ontario, L8S 4K1 (Canada)

    2007-08-30

    Recent studies have shown that dietary Ca{sup 2+} supplementation strongly inhibits uptake of Ca{sup 2+} and Cd at the fish gill. To better understand the influence of dietary Ca{sup 2+} on branchial Ca{sup 2+} transport, we examined the expression of two trout gill calcium transporters during waterborne and dietary Cd exposure, at two different levels of dietary Ca{sup 2+}. Quantitative polymerase chain reaction (PCR) was used to monitor epithelial calcium channel (ECaC) and sodium-calcium exchange (NCX) mRNA levels following 7-28 days of exposure to these treatments. In brief, juvenile rainbow trout (Oncorhynchus mykiss) were exposed to control, 3 {mu}g/L waterborne Cd, 500 mg/kg dietary Cd, or a combined 3 {mu}g/L waterborne plus 500 mg/kg dietary Cd exposure, supplemented with either 20 mg/g or 60 mg/g dietary calcium (Ca{sup 2+}). Two-way analysis of variance was used to discern the main effects of Cd exposure and dietary Ca{sup 2+} supplementation on ECaC and NCX mRNA levels. We found that dietary Ca{sup 2+} supplementation decreased significantly ECaC mRNA expression on days 14 and 21. In comparison, NCX mRNA levels were not influenced by dietary Ca{sup 2+} supplementation, but rather were significantly inhibited in the combined waterborne and dietary Cd exposure on day 7 alone. Statistical analysis found no interactive effects between Cd exposure and dietary Ca{sup 2+} exposure at any time point, except for day 28.This study provides evidence of the importance of nutritional status on the transcriptional regulation of ion transport at the fish gill. We discuss the importance of diet and nutritional status to the development of new regulatory approaches, such as the biotic ligand model, which currently do not account for the significance of diet on metal bioavailability in aquatic organisms.

  2. Limited effects of exogenous glucose during severe hypoxia and a lack of hypoxia-stimulated glucose uptake in isolated rainbow trout cardiac muscle

    DEFF Research Database (Denmark)

    Becker, Tracy A; Della Valle, Brian William; Gesser, Hans

    2013-01-01

    We examined whether exogenous glucose affects contractile performance of electrically paced ventricle strips from rainbow trout under conditions known to alter cardiomyocyte performance, ion regulation and energy demands. Physiological levels of d-glucose did not influence twitch force developmen...

  3. 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...

  4. Influence of probiotic, Lactobacillus plantarum on serum biochemical and immune parameters in vaccinated rainbow trout (Oncorhynchus mykiss against streptococcosis/lactococosis

    Directory of Open Access Journals (Sweden)

    Ali. M. Kane

    2016-10-01

    Full Text Available This study evaluated the effects of probiotic, Lactobacillus plantarum on serum biochemical and some immune parameters of immunized rainbow trout weighting 29.6±1.84 g, with streptococcosis/lactococosis vaccine at 16±1.5°C, for 60 days. A commercial diet was used as the control. Fish in the first treatment were immunized with streptococcosis/lactococosis vaccine in bathing route for 1 min. In the second group, the vaccinated trout were also fed diet containing L. plantarum (108 CFU g-1. In the third treatment, fish were only fed the diet supplemented with L. plantarum (108 CFU g-1. The results showed that vaccinated trout with or without L. plantarum feeding diets significantly decreased heterophils. Meanwhile it enhances serum lysozyme, alternative complement activities, antibody titer, total leukocytes, lymphocytes, and serum biochemical parameters, including ALP, IgM, and total protein levels compared to control groups. Moreover, the highest levels of above mentioned parameters were found in vaccinated fish that fed L. plantarum. In addition, the vaccinated fish that fed L. plantarum showed significantly elevated cholesterol levels compared to the control group. The results showed that the dietary L. plantarum improved the immunity of immunized trout with streptococcosis/lactococosis vaccine.

  5. Movement and survival of brown trout and rainbow trout in an ozark tailwater river

    Science.gov (United States)

    Quinn, J.W.; Kwak, T.J.

    2011-01-01

    We evaluated the movement of adult brown trout Salmo trutta and rainbow trout Oncorhynchus mykiss in relation to a catch-andrelease area in the White River downstream from Beaver Dam, Arkansas. Nine fish of each species were implanted with radio transmitters and monitored from July 1996 to July 1997. The 1.5- km river length of a catch-and-release area (closed to angler harvest) was greater than the total linear range of 72% of the trout (13 of 18 fish), but it did not include two brown trout spawning riffles, suggesting that it effectively protects resident fish within the catch-and-release area except during spawning. The total detected linear range of movement varied from 172 to 3,559 m for brown trout and from 205 to 3,023mfor rainbow trout. The movements of both species appeared to be generally similar to that in unregulated river systems. The annual apparent survival of both trout species was less than 0.40, and exploitation was 44%.Management to protect fish on spawning riffles may be considered if management for wild brown trout becomes a priority. ?? American Fisheries Society 2011.

  6. 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.

  7. Influence of bioassay volume, water column height, and octanol-water partition coefficient on the toxicity of pesticides to rainbow trout.

    Science.gov (United States)

    Altinok, Ilhan; Capkin, Erol; Boran, Halis

    2011-06-01

    Effects of water volume and water column height on toxicity of cypermethrin, carbaryl, dichlorvos, tetradifon, maneb, captan, carbosulfan endosulfan and HgCl₂ to juvenile rainbow trout (Oncorhynchus mykiss, 3.2 ± 0.7 g) were evaluated in different glass aquaria under static conditions. When fish were exposed to the chemical compounds in 23 cm water column height (25 L), their mortality ranged between 0% and 58%. At the same water volume, but lower water column height (9 cm), mortality of fish increased significantly and was in a range from 60% to 95%. At the same water column height, toxic effects of chemicals were significantly higher in 25 L water volume than that of 8.5 L, water except maneb which has lowest (-0.45) octanol-water partition coefficient value. Mortality rates ratio of 9 and 23 cm water column height ranged between 1.12 and 90 while mortality rates ratio of 9 and 25 L water volume ranged between 1.20 and 4.0. Because actual exposure concentrations were not affected by either water volume or water column height, we propose that increased pesticides' toxicity was related to an increase in bioassay volume, since more pesticide molecules were able to interact with or accumulate the fish. However, there seem to be no relationship between the effects of water volume, water column height and Kow value of chemicals with regard to toxicity in juvenile rainbow trout.

  8. Testing experimental subunit furunculosis vaccines for rainbow trout

    DEFF Research Database (Denmark)

    Marana, Moonika H.; Chettri, Jiwan Kumar; Skov, Jakob

    2016-01-01

    Aeromonas salmonicida subsp. salmonicida (AS) is the etiological agent of typical furunculosis in salmonid fish. The disease causes bacterial septicemia and is a major fish health problem in salmonid aquaculture worldwide, inducing high morbidity and mortality. In this study we vaccinated rainbow...... trout with subunit vaccines containing protein antigens that were selected based on an in silico antigen discovery approach. Thus, the proteome of AS strain A449 was analyzed by an antigen discovery platform and its proteins consequently ranked by their predicted ability to evoke protective immune...... response against AS. Fourteen proteins were prepared in 3 different experimental subunit vaccine combinations and used to vaccinate rainbow trout by intraperitoneal (i.p.) injection. We tested the proteins for their ability to elicit antibody production and protection. Thus, fish were exposed to virulent...

  9. Secondary immune response of rainbow trout following repeated immersion vaccination

    DEFF Research Database (Denmark)

    Jaafar, R. M.; Al-Jubury, A.; Chettri, J. K.

    2017-01-01

    Teleosts are able to raise a protective immune response, comprising both innate and adaptive elements, against various pathogens. This is the basis for a widespread use of vaccines, administered as injection or immersion, in the aquaculture industry. It has been described that repeated injection...... vaccination of fish raises a secondary immune response, consisting of rapid, accelerated and increased antibody reaction. This study reports how rainbow trout responds to repeated immersion vaccination against yersiniosis (ERM) caused by the bacterial pathogen Yersinia ruckeri. It was found that rainbow trout...... does not raise a classical secondary response following repeated immersion vaccination. Serum antibody titres were merely slightly increased even after three immunizations, using 30-s immersion into a bacterin consisting of formalin-inactivated Y. ruckeri (serotype O1, biotypes 1 and 2), performed over...

  10. Secondary immune response of rainbow trout following repeated immersion vaccination

    DEFF Research Database (Denmark)

    Jaafar, R. M.; Al-Jubury, Azmi; Chettri, Jiwan Kumar

    2018-01-01

    Teleosts are able to raise a protective immune response, comprising both innate and adaptive elements, against various pathogens. This is the basis for a widespread use of vaccines, administered as injection or immersion, in the aquaculture industry. It has been described that repeated injection...... vaccination of fish raises a secondary immune response, consisting of rapid, accelerated and increased antibody reaction. This study reports how rainbow trout responds to repeated immersion vaccination against yersiniosis (ERM) caused by the bacterial pathogen Yersinia ruckeri. It was found that rainbow trout...... does not raise a classical secondary response following repeated immersion vaccination. Serum antibody titres were merely slightly increased even after three immunizations, using 30-s immersion into a bacterin consisting of formalin-inactivated Y. ruckeri (serotype O1, biotypes 1 and 2), performed over...

  11. 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.

  12. Preservation of salted and smoked rainbow trout by irradiation

    International Nuclear Information System (INIS)

    Fiszer, W.; Zabielski, J.; Magnuski, T.

    1993-01-01

    The benefits of radiation treatment of ready-to-eat rainbow trout fillets manifest through the extention of lag period of bacterial regrowth during storage. The shelf-life of the fillets, which is declared by the producer as 14 days, may be doubled. No significant decrease in eating quality due to the treatment was found. The dose of 2 kGy combined with the smoking, salting, vacuum packaging and storage in 2 -3 C is satisfactory to achieve the goal. (orig.)

  13. 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

  14. Limnology of nine small lakes, Matanuska-Susitna Borough, Alaska, and the survival and growth rates of rainbow trout

    Science.gov (United States)

    Woods, P.F.

    1985-01-01

    The survival and growth rates of rainbow trout (Salmo gairdnieri) were concurrently measured with selected limnological characteristics in nine small (surface area Gasterosteus aculeatus) also influenced survival of rainbow trout but their effects were overshadowed by winterkill. Predictive capability was also reduced because of inconsistencies in rankings generated by each of the four limnological variables chosen as indicators of potential biological productivity. A lake ranked low in productivity by one variable was commonly ranked high in productivity by another variable. The survivability of rainbow trout stocked in lakes such as these nine may be a more important indicator of potential biomass production than are indicators of lake fertility. Assessments of a lake 's susceptibility to winterkill and the degree of competition with threespine stickleback are suggested as important topics for additional research. (Author 's abstract)

  15. Toxicokinetics of PFOS in rainbow trout

    Data.gov (United States)

    U.S. Environmental Protection Agency — This ScienceHub entry was developed for the published paper: Consoer et al., 2016, Toxicokinetics of perfluorooctane sulfonate in rainow trout (Oncorhynchus mykiss),...

  16. The effects of feed composition on the sensory quality of organic rainbow trout during ice storage

    DEFF Research Database (Denmark)

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

    fishmeal and a mixture of protein from organic vegetable, while the lipid sources were fish oil and organic oil from linseed, sunflower, rapeseed and grape seed. Sensory analysis was performed after 3, 5, 7 and 14 days of storage in ice. The results showed that both protein and lipid source in the feed can...... after 14 days of storage, indicating that vegetable protein in the feed increases the self-life of organic rainbow trout.......The focus of this work was to study which effects the type of protein and lipid source in the feed for organic Rainbow trout influences had on the sensory quality of final product. Two and four different protein and lipid sources were used in the experiment respectively. The protein sources were...

  17. 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

  18. 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...

  19. 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...

  20. 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...

  1. 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

  2. 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...

  3. A trial of two trouts: Comparing the impacts of rainbow and brown trout on a native galaxiid

    Science.gov (United States)

    Young, K.A.; Dunham, J.B.; Stephenson, J.F.; Terreau, A.; Thailly, A.F.; Gajardo, G.; de Leaniz, C. G.

    2010-01-01

    Rainbow trout Oncorhynchus mykiss and brown trout Salmo trutta are the world's two most widespread exotic fishes, dominate the fish communities of most cold-temperate waters in the southern hemisphere and are implicated in the decline and extirpation of native fish species. Here, we provide the first direct comparison of the impacts of rainbow and brown trout on populations of a native fish by quantifying three components of exotic species impact: range, abundance and effect. We surveyed 54 small streams on the island of Chilo?? in Chilean Patagonia and found that the rainbow trout has colonized significantly more streams and has a wider geographic range than brown trout. The two species had similar post-yearling abundances in allopatry and sympatry, and their abundances depended similarly on reach-level variation in the physical habitat. The species appeared to have dramatically different effects on native drift-feeding Aplochiton spp., which were virtually absent from streams invaded by brown trout but shared a broad sympatric range with rainbow trout. Within this range, the species' post-yearling abundances varied independently before and after controlling for variation in the physical habitat. In the north of the island, Aplochiton spp. inhabited streams uninvaded by exotic trouts. Our results provide a context for investigating the mechanisms responsible for apparent differences in rainbow and brown trout invasion biology and can help inform conservation strategies for native fishes in Chilo?? and elsewhere. ?? 2010 The Authors. Journal compilation ?? 2010 The Zoological Society of London.

  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. The intestinal microbiota in rainbow trout (Oncorhynchus Mykiss) is influenced by diet type and Yersinia Ruckeri challenge

    DEFF Research Database (Denmark)

    Ingerslev, Hans-Christian; Dalsgaard, Inger; Jørgensen, L. von Gersdorff

    colonization of pathogenic bacteria. The question is if the gut microbiota is also important in lower vertebrates such as fish? Is the microbiota related to the diet type and does it play a protective role in connection to pathogenic challenge? To examine these questions rainbow trout fry were fed two...... of reads belonging to phylum Firmicutes were significantly higher in the intestines of vegetable fed fish. The genera within phylum Firmicutes present in significantly higher amounts in vegetable fed fish were Weissella, Leuconostoc and Streptococcus. Genus Aeromonas from the γ-proteobacteria class...... was also present in significantly higher amounts in the vegetable fed fish. When challenged with Yersinia ruckeri, fish with a high amount of sequence reads belonging to genus Yersinia had a significantly lower amount of reads from the order Burkholderiales relative to non-infected control fish and fish...

  6. In vitro characterization of cadmium and zinc uptake via the gastro-intestinal tract of the rainbow trout (Oncorhynchus mykiss): Interactive effects and the influence of calcium

    International Nuclear Information System (INIS)

    Ojo, Adeola A.; Wood, Chris M.

    2008-01-01

    An in vitro gut sac technique was employed to study whether Cd and Zn uptake mechanisms in the gastro-intestinal tract of the rainbow trout are similar to those at the gills, where both metals are taken up via the Ca transport pathway. Metal accumulation in surface mucus, in the mucosal epithelium, and transport into the blood space were assayed using radiolabelled Cd or Zn concentrations of 50 μmol L -1 in the luminal (internal) saline. Elevated luminal Ca (10 or 100 mmol L -1 versus 1 mmol L -1 ) reduced Cd uptake into all three phases by approximately 60% in the stomach, but had no effect in the anterior, mid, or posterior intestine. This finding is in accordance with recent in vivo evidence that Ca is taken up mainly via the stomach, and that high [Ca] diets inhibit Cd accumulation from the food specifically in this section of the tract. In contrast, 10 mmol L -1 luminal Ca had no effect on Zn transport in any section, whereas 100 mmol L -1 Ca stimulated Zn uptake, by approximately threefold, into all three phases in the stomach only. There was no influence of elevated luminal Zn (10 mmol L -1 ) on Cd uptake in the stomach or anterior intestine, or of high Cd (10 mmol L -1 ) on Zn uptake in these sections. However, high [Zn] stimulated Cd transport into the blood space but inhibited accumulation in the mucosal epithelium and/or mucus-binding in the mid and posterior intestine, whereas high [Cd] exerted a reciprocal effect in the mid-intestine only. We conclude that Cd uptake occurs via an important Ca-sensitive mechanism in the stomach which is different from that at the gills, while Cd transport mechanisms in the intestine are not directly Ca-sensitive. Zn uptake does not appear to involve Ca uptake pathways, in contrast to the gills. These results are discussed in the context of other possible Cd and Zn transport pathways, and the emerging role of the stomach as an organ of divalent metal uptake

  7. In vitro characterization of cadmium and zinc uptake via the gastro-intestinal tract of the rainbow trout (Oncorhynchus mykiss): Interactive effects and the influence of calcium

    Energy Technology Data Exchange (ETDEWEB)

    Ojo, Adeola A. [Department of Biology, McMaster University, 1280 Main Street West, Hamilton, Ontario, L8S 4K1 (Canada)], E-mail: adeolaojo25@yahoo.com; Wood, Chris M. [Department of Biology, McMaster University, 1280 Main Street West, Hamilton, Ontario, L8S 4K1 (Canada)], E-mail: woodcm@mcmaster.ca

    2008-08-11

    An in vitro gut sac technique was employed to study whether Cd and Zn uptake mechanisms in the gastro-intestinal tract of the rainbow trout are similar to those at the gills, where both metals are taken up via the Ca transport pathway. Metal accumulation in surface mucus, in the mucosal epithelium, and transport into the blood space were assayed using radiolabelled Cd or Zn concentrations of 50 {mu}mol L{sup -1} in the luminal (internal) saline. Elevated luminal Ca (10 or 100 mmol L{sup -1}versus 1 mmol L{sup -1}) reduced Cd uptake into all three phases by approximately 60% in the stomach, but had no effect in the anterior, mid, or posterior intestine. This finding is in accordance with recent in vivo evidence that Ca is taken up mainly via the stomach, and that high [Ca] diets inhibit Cd accumulation from the food specifically in this section of the tract. In contrast, 10 mmol L{sup -1} luminal Ca had no effect on Zn transport in any section, whereas 100 mmol L{sup -1} Ca stimulated Zn uptake, by approximately threefold, into all three phases in the stomach only. There was no influence of elevated luminal Zn (10 mmol L{sup -1}) on Cd uptake in the stomach or anterior intestine, or of high Cd (10 mmol L{sup -1}) on Zn uptake in these sections. However, high [Zn] stimulated Cd transport into the blood space but inhibited accumulation in the mucosal epithelium and/or mucus-binding in the mid and posterior intestine, whereas high [Cd] exerted a reciprocal effect in the mid-intestine only. We conclude that Cd uptake occurs via an important Ca-sensitive mechanism in the stomach which is different from that at the gills, while Cd transport mechanisms in the intestine are not directly Ca-sensitive. Zn uptake does not appear to involve Ca uptake pathways, in contrast to the gills. These results are discussed in the context of other possible Cd and Zn transport pathways, and the emerging role of the stomach as an organ of divalent metal uptake.

  8. Kootenai River fisheries investigations: rainbow and bull trout recruitment: annual progress report 1999; ANNUAL

    International Nuclear Information System (INIS)

    Walters, Jody P.; Downs, Christopher Charles

    2001-01-01

    Our 1999 objectives were to determine sources of rainbow trout Oncorhynchus mykiss and bull trout Salvelinus confluentus spawning and recruitment in the Idaho reach of the Kootenai River. We used a rotary-screw trap to capture juvenile trout to determine age at out-migration and to estimate total out-migration from the Boundary Creek drainage to the Kootenai River. The out-migrant estimate for March through August 1999 was 1,574 (95% C. I.= 825-3,283) juvenile rainbow trout. Most juveniles out-migrated at age-2 and age-3. No out-migrating bull trout were caught. Five of 17 rainbow trout radio-tagged in Idaho migrated upstream into Montana waters during the spawning season. Five bull trout originally radio-tagged in O'Brien Creek, Montana in early October moved downstream into Idaho and British Columbia by mid-October. Annual angler exploitation for the rainbow trout population upstream of Bonners Ferry, Idaho was estimated to be 58%. Multi-pass depletion estimates for index reaches of Caboose, Curley, and Debt creeks showed 0.20, 0.01, and 0.13 rainbow trout juveniles/m(sup 2), respectively. We estimated rainbow trout (180-415 mm TL) standing stock of 1.6 kg/ha for the Hemlock Bar reach (29.4 ha) of the Kootenai River, similar to the 1998 estimate. Recruitment of juvenile rainbow and bull trout from Idaho tributaries is not sufficient to be the sole source of subsequent older fish in the mainstem Kootenai River. These populations are at least partly dependent on recruitment from Montana waters. The low recruitment and high exploitation rate may be indicators of a rainbow trout population in danger of further decline

  9. 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...

  10. 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...

  11. The effect of deposited fine sediment on summer survival and growth of rainbow trout in riffles of a small stream

    Science.gov (United States)

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

    2009-01-01

    Elevated fine-sediment inputs to streams can alter a variety of conditions and processes, including the amount of fine sediment stored in riffles. We sought to measure the influence of deposited fine sediment on the survival and growth of juvenile rainbow trout Oncorhynchus mykiss (106–130 mm fork length) using a field experiment that included 18 enclosures in riffles...

  12. 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

  13. 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.

  14. 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.

  15. Elimination of copper in tissues and organs of rainbow trout

    Directory of Open Access Journals (Sweden)

    Gaye Dogan

    2011-01-01

    Full Text Available Copper (Cu elimination was investigated in the tissue and organs of rainbow trout (Oncorhynchus mykiss, Walbaum, 1792, after Cu-free diets exposure. In the current study, fish were fed to satiation on diets containing 0.022 (Group 1; Control, 0.043 (Group 2, 0.123 (Group 3, 0.424 (Group 4 g Cu*kg-1 diet for 60 days before elimination experiment. A total of 288 fish (mean weight 84.28±1.05 g were randomly transferred to 12 fibreglass tanks. The fish were fed the Cu-free diet twice daily, until apparent satiation, during 60 days. Subsequently, the experiment was established for a period of elimination, during which samples were taken at days 15, 30, 45 and 60. Cu concentration in the muscle, gill tissue, digestive system, liver and whole body of fish were determined after 60 days depuration. Cu concentrations in tissues of rainbow trout decreased during depuration period, and the order of Cu elimination in tissue and organs of rainbow trout was: digestive system (73.1 %, then gill (41.1 %, muscle (31.5 % and liver (17.2 % for group 2; digestive system (74.1%, then muscle (65.8%, gill (60.0% and liver (34.6% for group 3; and digestive system (85.8%, then muscle (80.8%, liver (50.5% and less/equal in gill (50.2% for group 4. In statistical analysis, both groups and time were significant factors (P less than 0.05 on elimination rate. Moreover, significant interaction between groups and time were identified on elimination rate. Digestive system showed the fastest elimination rates of Cu at all groups compared with other tissues.

  16. Effect of electric barrier on passage and physical condition of juvenile and adult rainbow trout

    Science.gov (United States)

    Layhee, Megan J.; Sepulveda, Adam; Shaw, Amy; Smuckall, Matthew; Kapperman, Kevin; Reyes, Alejandro

    2016-01-01

    Electric barriers can inhibit passage and injure fish. Few data exist on electric barrier parameters that minimize these impacts and on how body size affects susceptibility, especially to nontarget fish species. The goal of this study was to determine electric barrier voltage and pulse-width settings that inhibit passage of larger bodied rainbow trout Oncorhynchus mykiss (215–410 mm fork length) while allowing passage of smaller bodied juvenile rainbow trout (52–126 mm) in a static laboratory setting. We exposed rainbow trout to 30-Hz pulsed-direct current voltage gradients (0.00–0.45 V cm−1) and pulse widths (0.0–0.7 ms) and recorded their movement, injury incidence, and mortality. No settings tested allowed all juveniles to pass while impeding all adult passage. Juvenile and adult rainbow trout avoided the barrier at higher pulse widths, and fewer rainbow trout passed the barrier at 0.7-ms pulse width compared to 0.1 ms and when the barrier was turned off. We found no effect of voltage gradient on fish passage. No mortality occurred, and we observed external bruising in 5 (7%) juvenile rainbow trout and 15 (21%) adult rainbow trout. This study may aid managers in selecting barrier settings that allow for increased juvenile passage.

  17. 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...

  18. Zooplankton size selection relative to gill raker spacing in rainbow trout

    Science.gov (United States)

    Budy, P.; Haddix, T.; Schneidervin, R.

    2005-01-01

    Rainbow trout Oncorhynchus mykiss are one of the most widely stocked salmonids worldwide, often based on the assumption that they will effectively utilize abundant invertebrate food resources. We evaluated the potential for feeding morphology to affect prey selection by rainbow trout using a combination of laboratory feeding experiments and field observations in Flaming Gorge Reservoir, Utah-Wyoming. For rainbow trout collected from the reservoir, inter-gill raker spacing averaged 1.09 mm and there was low variation among fish overall (SD = 0.28). Ninety-seven percent of all zooplankton observed in the diets of rainbow trout collected in the reservoir were larger than the interraker spacing, while only 29% of the zooplankton found in the environment were larger than the interraker spacing. Over the size range of rainbow trout evaluated here (200-475 mm), interraker spacing increased moderately with increasing fish length; however, the size of zooplankton found in the diet did not increase with increasing fish length. In laboratory experiments, rainbow trout consumed the largest zooplankton available; the mean size of zooplankton observed in the diets was significantly larger than the mean size of zooplankton available. Electivity indices for both laboratory and field observations indicated strong selection for larger-sized zooplankton. The size threshold at which electivity switched from selection against smaller-sized zooplankton to selection for larger-sized zooplankton closely corresponded to the mean interraker spacing for both groups (???1-1.2 mm). The combination of results observed here indicates that rainbow trout morphology limits the retention of different-sized zooplankton prey and reinforces the importance of understanding how effectively rainbow trout can utilize the type and sizes of different prey available in a given system. These considerations may improve our ability to predict the potential for growth and survival of rainbow trout within and

  19. Individual condition, standard metabolic rate, and rearing temperature influence steelhead and rainbow trout (Oncorhynchus mykiss) life histories

    Science.gov (United States)

    Matthew R. Sloat; Gordon H. Reeves

    2014-01-01

    We reared juvenile Oncorhychus mykiss with low and high standard metabolic rates (SMR) under alternative thermal regimes to determine how these proximate factors influence life histories in a partially migratory salmonid fish. High SMR significantly decreased rates of freshwater maturation and increased rates of smoltification in females, but not...

  20. Effects of water temperature and fish size on predation vulnerability of juvenile humpback chub to rainbow trout and brown trout

    Science.gov (United States)

    Ward, David L.; Morton-Starner, Rylan

    2015-01-01

    Predation on juvenile native fish by introduced Rainbow Trout and Brown Trout is considered a significant threat to the persistence of endangered Humpback Chub Gila cypha in the Colorado River in the Grand Canyon. Diet studies of Rainbow Trout and Brown Trout in Glen and Grand canyons indicate that these species do eat native fish, but impacts are difficult to assess because predation vulnerability is highly variable, depending on prey size, predator size, and the water temperatures under which the predation interactions take place. We conducted laboratory experiments to evaluate how short-term predation vulnerability of juvenile native fish changes in response to fish size and water temperature using captivity-reared Humpback Chub, Bonytail, and Roundtail Chub. Juvenile chub 45–90 mm total length (TL) were exposed to adult Rainbow and Brown trouts at 10, 15, and 20°C to measure predation vulnerability as a function of water temperature and fish size. A 1°C increase in water temperature decreased short-term predation vulnerability of Humpback Chub to Rainbow Trout by about 5%, although the relationship is not linear. Brown Trout were highly piscivorous in the laboratory at any size > 220 mm TL and at all water temperatures we tested. Understanding the effects of predation by trout on endangered Humpback Chub is critical in evaluating management options aimed at preserving native fishes in Grand Canyon National Park.

  1. Estrogen receptor mRNA in mineralized tissues of rainbow trout: calcium mobilization by estrogen.

    Science.gov (United States)

    Armour, K J; Lehane, D B; Pakdel, F; Valotaire, Y; Graham, R; Russell, R G; Henderson, I W

    1997-07-07

    RT-PCR was undertaken on total RNA extracts from bone and scales of the rainbow trout, Oncorhynchus mykiss. The rainbow trout estrogen receptor (ER)-specific primers used amplified a single product of expected size from each tissue which, using Southern blotting, strongly hybridized with a 32P-labelled rtER probe under stringent conditions. These data provide the first in vivo evidence of ER mRNA in bone and scale tissues of rainbow trout and suggest that the effects of estrogen observed in this study (increased bone mineral and decreased scale mineral contents, respectively) may be mediated directly through ER.

  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. Diurnal stream habitat use of juvenile Atlantic salmon, brown trout and rainbow trout in winter

    Science.gov (United States)

    Johnson, J. H.; Douglass, K.A.

    2009-01-01

    The diurnal winter habitat of three species of juvenile salmonids was examined in a tributary of Skaneateles Lake, NY to compare habitat differences among species and to determine if species/age classes were selecting specific habitats. A total of 792 observations were made on the depth, velocity, substrate and cover (amount and type) used by sympatric subyearling Atlantic salmon, subyearling brown trout and subyearling and yearling rainbow trout. Subyearling Atlantic salmon occurred in shallower areas with faster velocities and less cover than the other salmonid groups. Subyearling salmon was also the only group associated with substrate of a size larger than the average size substrate in the study reach during both winters. Subyearling brown trout exhibited a preference for vegetative cover. Compared with available habitat, yearling rainbow trout were the most selective in their habitat use. All salmonid groups were associated with more substrate cover in 2002 under high flow conditions. Differences in the winter habitat use of these salmonid groups have important management implications in terms of both habitat protection and habitat enhancement.

  4. Variability of kokanee and rainbow trout food habits, distribution, and population dynamics, in an ultraoligotrophic lake with no manipulative management

    Science.gov (United States)

    Buktenica, M.W.; Girdner, S.F.; Larson, G.L.; McIntire, C.D.

    2007-01-01

    Crater Lake is a unique environment to evaluate the ecology of introduced kokanee and rainbow trout because of its otherwise pristine state, low productivity, absence of manipulative management, and lack of lotic systems for fish spawning. Between 1986 and 2004, kokanee displayed a great deal of variation in population demographics with a pattern that reoccurred in about 10 years. We believe that the reoccurring pattern resulted from density dependent growth, and associated changes in reproduction and abundance, driven by prey resource limitation that resulted from low lake productivity exacerbated by prey consumption when kokanee were abundant. Kokanee fed primarily on small-bodied prey from the mid-water column; whereas rainbow trout fed on large-bodied prey from the benthos and lake surface. Cladoceran zooplankton abundance may be regulated by kokanee. And kokanee growth and reproductive success may be influenced by the availability of Daphnia pulicaria, which was absent in zooplankton samples collected annually from 1990 to 1995, and after 1999. Distribution and diel migration of kokanee varied over the duration of the study and appeared to be most closely associated with prey availability, maximization of bioenergetic efficiency, and fish density. Rainbow trout were less abundant than were kokanee and exhibited less variation in population demographics, distribution, and food habits. There is some evidence that the population dynamics of rainbow trout were in-part related to the availability of kokanee as prey. ?? 2007 Springer Science+Business Media B.V.

  5. Developing acute-to-chronic toxicity ratios for lead, cadmium, and zinc using rainbow trout, a mayfly, and a midge

    Science.gov (United States)

    Mebane, C.A.; Hennessy, D.P.; Dillon, F.S.

    2008-01-01

    In order to estimate acute-to-chronic toxicity ratios (ACRs) relevant to a coldwater stream community, we exposed rainbow trout (Oncorhynchus mykiss) to cadmium (Cd), lead (Pb), and zinc (Zn) in 96-h acute and 60+ day early-life stage (ELS) exposures. We also tested the acute and sublethal responses of a mayfly (Baetis tricaudatus) and a midge (Chironomus dilutus, formerly C. tentans) with Pb. We examine the statistical interpretation of test endpoints and the acute-to-chronic ratio concept. Increasing the number of control replicates by 2 to 3x decreased the minimum detectable differences by almost half. Pb ACR estimates mostly increased with increasing acute resistance of the organisms (rainbow trout ACRs influenced ACR estimates by up to a factor of four. When calculated using the geometric means of the no- and lowest-observed effect concentrations, ACRs with rainbow trout and Cd were 0.6 and 0.95; Zn about 1.0; and for Pb 3.3 and 11. The comparable Pb ACRs for the mayfly and Chironomus were 5.2 and 51 respectively. Our rainbow trout ACRs with Pb were about 5-20x lower than earlier reports with salmonids. We suggest discounting previous ACR results that used larger and older fish in their acute tests. ?? 2007 GovernmentEmployee: U.S. Geological Survey.

  6. Temperature influences the expression profiling of immune response genes in rainbow trout following DNA vaccination and VHS virus infection

    DEFF Research Database (Denmark)

    Einer-Jensen, Katja; Gautier, Laurent; Rasmussen, Jesper Skou

    balancing mechanism of the immune system. An experimental VHSV challenge was performed 7 weeks pv. Similar protection levels of approximately 10% mortality were found for the vaccinated fish, regardless of temperature during immunisation and challenge, whereas the course and level of mortality among...... an early unspecific antiviral response as well as a long-lasting specific protection. However, temperature appears to influence immune response with respect to the nature and duration of the protective mechanisms. In this study, groups of fish were temperature acclimated, vaccinated and challenged at three...... different temperatures (5, 10 and 15ºC). Tissue and organ samples were collected at numerous time points post vaccination (pv) and post viral challenge (pch). Then, gene expression levels of a two immune genes (Vig-1 and Mx3) involved in unspecific antiviral response mechanisms were determined by Q...

  7. 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.

  8. Molecular analysis of population genetic structure and recolonization of rainbow trout following the Cantara spill

    Science.gov (United States)

    Nielsen, J.L.; Heine, Erika L.; Gan, Christina A.; Fountain, Monique C.

    2000-01-01

    Mitochondrial DNA (mtDNA) sequence and allelic frequency data for 12 microsatellite loci were used to analyze population genetic structure and recolonization by rainbow trout, Oncorhynchus mykiss, following the 1991 Cantara spill on the upper Sacramento River, California. Genetic analyses were performed on 1,016 wild rainbow trout collected between 1993 and 1996 from the mainstem and in 8 tributaries. Wild trout genotypes were compared to genotypes for 79 Mount Shasta Hatchery rainbow trout. No genetic heterogeneity was found 2 years after the spill (1993) between tributary populations and geographically proximate mainstem fish, suggesting recolonization of the upper mainstem directly from adjacent tributaries. Trout collections made in 1996 showed significant year-class genetic variation for mtDNA and microsatellites when compared to fish from the same locations in 1993. Five years after the spill, mainstem populations appeared genetically mixed with no significant allelic frequency differences between mainstem populations and geographically proximate tributary trout. In our 1996 samples, we found no significant genetic differences due to season of capture (summer or fall) or sampling technique used to capture rainbow trout, with the exception of trout collected by electrofishing and hook and line near Prospect Avenue. Haplotype and allelic frequencies in wild rainbow trout populations captured in the upper Sacramento River and its tributaries were found to differ genetically from Mount Shasta Hatchery trout for both years, with the notable exception of trout collected in the lower mainstem river near Shasta Lake, where mtDNA and microsatellite data both suggested upstream colonization by hatchery fish from the reservoir. These data suggest that the chemical spill in the upper Sacramento River produced significant effects over time on the genetic population structure of rainbow trout throughout the entire upper river basin.

  9. Influences of incubation temperature and various saccharides on the production of organic acids and gases by gut microbes of rainbow trout Oncorhynchus mykiss in a micro-scale batch culture.

    Science.gov (United States)

    Kihara, M; Sakata, T

    2001-08-01

    We studied the influence of incubation temperature and additional saccharides on the metabolism of hindgut microbes of the rainbow trout Oncorhynchus mykiss in a 50 microl-scale batch culture system. Intestinal contents of rainbow trout reared at 15 degrees C were incubated with glucose, lactosucrose, sodium alginate or colloidal chitin (each 10 g/l) at 15 degrees C or 25 degrees C for 12 h. Levels of organic acids at 0 h and 12 h of incubation were quantified with HPLC. We also monitored gas release from these cultures during incubation. The main product was iso-butyric acid, except for the cultures with colloidal chitin where no net production of organic acids was observed. We detected higher levels of iso-butyric acid in cultures with lactosucrose than in the other cultures. Net production of this acid was less in cultures with colloidal chitin than in blank cultures. The volume of released gas was larger when incubated at 25 degrees C than at 15 degrees C. Cultures with colloidal chitin released more gas than blank cultures when they were incubated at 15 degrees C. Cultures with sodium alginate released less gas than blank cultures irrespective of incubation temperature. These results indicate that the hindgut microbes of this carnivorous fish mainly produce branched-chain fatty acids, very likely by microbial digestion of nitrogenous materials rather than saccharides. However, additional saccharides affected production of branched-chain fatty acids. The influence of incubation temperature in the present study also suggested that the environmental temperature of host fish should affect microbial digestion in the fish gut.

  10. 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...

  11. Using Rainbow Trout to Measure Arsenic Toxicity in Water

    Directory of Open Access Journals (Sweden)

    Kazem Naddafi

    2006-06-01

    Full Text Available The purpose of this study is to determine arsenic toxicity on rainbow trout. Acute toxicity of arsenic was determined by measuring the lethal effects on rainbow trout in static conditions. Five aquariums of 25×30×30 cm with five concentrations of 5,10,15,20 and 25 mg/L of arsenic were prepared and then ten fishes were added to each concentration. Also one aquarium with similar conditions was considered as a control with no arsenic solution. Hardness, temperature and dissolved oxygen of dilution water were determined by standard methods, and concentration of dissolved oxygen, pH and temperature of solution test in time periods of 2,4,6,8,24,48,72 and 96 hrs were measured. Water temperature of aquarium was regulated by circulation of water in refrigerator through indirect conduction with solution test. LC50 was measured at intervals of 24,48,72 and 96 hrs by SPSS software and respectively showed 28.13,21.77,15.78 and 12.72 mg/L.Probit curve was drawn by Harvard Chart XL software, and LC50 curve was drawn by Excel software.

  12. [Influence of an elevation of the temperature of water on the digestibility of dry matter, nitrogen and energy of food distributed to the rainbow trout (Salmo gairdneri Rich)].

    Science.gov (United States)

    Choubert, G; Fauconneau, B; Luquet, P

    1982-01-01

    Rainbow trout adapted to a water temperature of 10 degrees C were subjected to an abrupt rise in temperature (from 10 to 18 degrees C) in a 24-h period. Fish maintained in recirculated water were fed to satiation twice a day and their feed intakes were recorded. Changes in dry matter, nitrogen and energy digestibility were measured each day at 10 degrees C and during the course of acclimatation to 18 degrees C. Low water temperature (10 degrees C) was characterized by a feed intake of 1.84 g (DM)/fish/day; digestibility values were as follows: dry matter 62.15 p. 100, nitrogen 86.91 p. 100, energy 70.60 p. 100. High water temperature (18 degrees C) was characterized by a feed intake of 3.75 g (DM)/fish/day; digestibility values were as follows: dry matter 66.08 p. 100, nitrogen 89.57 p. 100, energy 73.52 p. 100. The daily patterns in digestibility were affected by the rise in temperature. The digestibility values were stabilized by day 7 after the positive thermal shock.

  13. 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

  14. 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.

  15. 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...

  16. 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...

  17. Digestibility in selected rainbow trout families and relation to growth and feed utilisation

    DEFF Research Database (Denmark)

    Rasmussen, Richard Skøtt; Jokumsen, Alfred

    2009-01-01

    Experiments have been carried out aimed at clarifying variations in the digestibility of dietary nutrients in rainbow trout families and studying how differences in digestibility may be related to growth and feed utilisation at various growth rates. The digestibility of protein, lipid...... the digestibility of protein, lipid, nitrogen-free extracts and dry matter was measured. Taken as a whole, our results indicate that selective breeding still offers a large potential for improved growth and feed utilisation in rainbow trout strains. In the first study, family Dc showed a higher specific growth rate......, carbohydrates (nitrogen-free extracts, NFE) and dry matter was analysed in two experiments involving eight rainbow trout families [Ab, Ba, Cd, Dc (first study); V, X, Y, Z (second study)]. In the first experiment rainbow trout were reared for 128 days at 13.0A degrees C, and in the second experiment, they were...

  18. 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

  19. 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...

  20. 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...

  1. 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...

  2. 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...

  3. 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.

  4. 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.

  5. Hermetia illucens meal as fish meal replacement for rainbow trout on farm

    OpenAIRE

    Stadtlander, Timo; Stamer, Andreas; Buser, Andrea; Wohlfahrt, Jens; Leiber, Florian; Sandrock, Christoph

    2017-01-01

    In a 7-week on-farm feeding trial rainbow trout (Oncorhynchus mykiss) were provided with a diet containing 28% mechanically de-fatted insect meal prepared from larvae of the black soldier fly, Hermetia illucens (HIM) and compared to a control that received a certified organic and fishmeal based diet. In the test diet insect meal replaced almost 50% of the fishmeal. The whole experiment was conducted under practical conditions on an organically certified rainbow trout farm in Switzerland. Fish...

  6. Organic diets are equally good for rainbow trout fry as conventional diets

    DEFF Research Database (Denmark)

    Madsen, Lone; Ingerslev, Hans Christian; Dalsgaard, Inger

    2014-01-01

    Rainbow trout (Oncorhynchus mykiss) is the dominant fish species in Danish freshwater aquaculture and the annual production is about 30.000 tonnes. Only a minor part of this production is organic, but the proportion of farmed organic rainbow trout is continuously increasing. The aim of the projec...... ingredients are of organic or conventional origin. Furthermore, fish fed organic diets appear to acquire the same health status as fish fed conventional diets....

  7. 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...

  8. OCCURRENCE OF INFECTIOUS PANCREATIC NECROSIS VIRUS (IPNV IN FARMED RAINBOW TROUT (ONCHORHYNCHUS MYKISS IN KOSOVO

    Directory of Open Access Journals (Sweden)

    Agim Rexhepi

    2013-10-01

    Full Text Available 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 broodfish. In total, 467 fishes from 113 (pools in 10 rainbow trout aquaculture facilities were screened. Laboratory analysis was performed at the TGD (Tiergesundheitsdienst Bayern e. V laboratory in Germany using the biomolecular method of RT-PCR and nested-PCR. The Infectious Pancreatic Necrosis virus was detected in seven trout farms, and prevalence from total samples (pools was 11.5 %. This is the first research and report for IPN virus diagnosis in farmed rainbow trout fry, on-growing fish and broodfish in Kosovo. Keywords: Rainbow trout, viral diseases, IPN, RT-PCR, nested PCR

  9. Rainbow trout estrogen receptor (ER) competitive bindng and vitellogenin induction agonism/antagonism data for 94 chemicals

    Data.gov (United States)

    U.S. Environmental Protection Agency — This dataset is from screening 94 diverse chemicals for estrogen receptor (ER) activation in a competitive rainbow trout ER binding assay and a trout liver slice...

  10. BIOMASS AND DENSITY OF BROWN AND RAINBOW TROUT IN NEW MEXICO STREAMS

    Directory of Open Access Journals (Sweden)

    Srečko Lainer

    1995-03-01

    Full Text Available Mean stream numerical density of the brown trout (Salmo trutta m. fario Linnaeus, 1758 and the rainbow trout (Onchorhynchus mykiss Walbaum, 1792 was 0.090 fish/m2 of which brown trout averaged 69% (72% in total biomass in 15 high-elevation New Mexico streams (1,661-2,560 m above sea level. Total trout density varied from 0.008/m2 in 1988 and 1989. Mean trout density ranged between 0.023-0.121 fish/m2 at site s open to public fishing. Considerably higher densities (0.142-0.409 fish/m2 were observed at sites closed for fishing. In the seven selected streams shared by both species, brown trout density exceeded rainbow trout density except at the two sites closed to fishing. Brown trout were stocked only as fingerlings (average 7,000 fish/stream/year while rainbow trout were stocked only in harvestable sizes (11,000 fish/stream/year. Reported total trout yield rates exceeded the total number of fish estimated to be in the stream by 1.01 to 11.63 in most small streams open to fishing. The proportional stock density (PSD ranged between O and 50 percent. Streams with low to moderate intensities of fishing had the highest PSD.

  11. High temperature increases the masculinization rate of the all-female (XX) rainbow trout "Mal" population.

    Science.gov (United States)

    Valdivia, Karina; Jouanno, Elodie; Volff, Jean-Nicolas; Galiana-Arnoux, Delphine; Guyomard, René; Helary, Louise; Mourot, Brigitte; Fostier, Alexis; Quillet, Edwige; Guiguen, Yann

    2014-01-01

    Salmonids are generally considered to have a robust genetic sex determination system with a simple male heterogamety (XX/XY). However, spontaneous masculinization of XX females has been found in a rainbow trout population of gynogenetic doubled haploid individuals. The analysis of this masculinization phenotype transmission supported the hypothesis of the involvement of a recessive mutation (termed mal). As temperature effect on sex differentiation has been reported in some salmonid species, in this study we investigated in detail the potential implication of temperature on masculinization in this XX mal-carrying population. Seven families issued from XX mal-carrying parents were exposed from the time of hatching to different rearing water temperatures ((8, 12 and 18°C), and the resulting sex-ratios were confirmed by histological analysis of both gonads. Our results demonstrate that masculinization rates are strongly increased (up to nearly two fold) at the highest temperature treatment (18°C). Interestingly, we also found clear differences between temperatures on the masculinization of the left versus the right gonads with the right gonad consistently more often masculinized than the left one at lower temperatures (8 and 12°C). However, the masculinization rate is also strongly dependent on the genetic background of the XX mal-carrying families. Thus, masculinization in XX mal-carrying rainbow trout is potentially triggered by an interaction between the temperature treatment and a complex genetic background potentially involving some part of the genetic sex differentiation regulatory cascade along with some minor sex-influencing loci. These results indicate that despite its rather strict genetic sex determinism system, rainbow trout sex differentiation can be modulated by temperature, as described in many other fish species.

  12. 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...

  13. 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...

  14. Fate of the isoprenoid hydrocarbon, pristane, in rainbow trout

    International Nuclear Information System (INIS)

    Le Bon, A.M.; Cravedi, J.P.; Tulliez, J.

    1987-01-01

    The excretion routes and tissue distribution of [ 3 H]pristane were measured in rainbow trout, Salmo gairdneri, after a single intragastric dose (0.1 mg). This branched-alkane was quickly and largely absorbed. The balance study showed that the major routes of excretion were fecal (40.4% of the dose) and branchial (39.6%). In feces radioactivity was exclusively due to [ 3 H]pristane, whereas 3 H resulting from gill excretion was principally associated with tritiated water. Only 2.6% of the radioactivity was cleared via the kidneys and found in the urine as metabolites. After 48 hr, no hydrocarbon accumulation was observed in gall bladder, while in liver and fat, respectively, 69 and 34% of the radioactivity originated from pristane, the rest of the labeling being mostly associated with lipid components

  15. Periodic depuration of anthracene metabolites by rainbow trout

    International Nuclear Information System (INIS)

    Linder, G.; Bergman, H.L.

    1984-01-01

    Rainbow trout Salmo gairdneri, statically exposed to 36 μg/liter anthracene (including 9- 14 C-C anthracene), bioconcentrated the polynuclear aromatic hydrocarbon 200 times the exposure concentration over 18 hours. Then, during a 96-hour clearance periods, mass-balance analysis of fish and water samples indicated that anthracene was rapidly converted to polar metabolites(s), then eliminated periodically. Maximum depuration occurred during the dark phase of a 16-hour-light: 8-hour-dark photocycle. Of the 2-3% contribution of 14 C metabolites(s) to the total 14 C residue, nearly half came from the bile. This periodic depuration may be circadian, although this requires confirmation by further work; to the extent it affects metabolic fate of bioconcentrated organics, periodic depuration undoubtedly contributes to differences between predicted and observed bioconcentration factors

  16. 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...

  17. Immune response in rainbow trout against infection with Flavobacterium psychrophilum

    DEFF Research Database (Denmark)

    Henriksen, Maya Maria Mihályi; Kania, Per; Madsen, Lone

    farmers control the disease with antibiotics. The pathogen has a limited ability to cause disease in an experimental setting without applying a stressor. A bath-model using 150mg/L H2O2 for 60 minutes as a stressor was used 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. Bath infections were carried out in 107 CFU/ml F. psychrophilum bath solution and control groups were bathed in sterile medium. Samples from all internal organs, head and skin were taken before pathogen exposure...

  18. Response of rainbow trout transcriptome to model chemical contaminants

    International Nuclear Information System (INIS)

    Koskinen, Heikki; Pehkonen, Petri; Vehniaeinen, Eeva; Krasnov, Aleksei; Rexroad, Caird; Afanasyev, Sergey; Moelsa, Hannu; Oikari, Aimo

    2004-01-01

    We used high-density cDNA microarray in studies of responses of rainbow trout fry at sublethal ranges of β-naphthoflavone, cadmium, carbon tetrachloride, and pyrene. The differentially expressed genes were grouped by the functional categories of Gene Ontology. Significantly different response to the studied compounds was shown by a number of classes, such as cell cycle, apoptosis, signal transduction, oxidative stress, subcellular and extracellular structures, protein biosynthesis, and modification. Cluster analysis separated responses to the contaminants at low and medium doses, whereas at high levels the adaptive reactions were masked with general unspecific response to toxicity. We found enhanced expression of many mitochondrial proteins as well as genes involved in metabolism of metal ions and protein biosynthesis. In parallel, genes related to stress and immune response, signal transduction, and nucleotide metabolism were down-regulated. We performed computer-assisted analyses of Medline abstracts retrieved for each compound, which helped us to indicate the expected and novel findings

  19. AEROMONAS SALMONICIDA INFECTION IN VACCINATED RAINBOW TROUT

    DEFF Research Database (Denmark)

    Chettri, Jiwan Kumar; Skov, Jakob; Mohammad, Rezkar Jaafar

    In vivo testing of any candidate vaccine is influenced by the choice of challenge method and the external environmental conditions. In the present study, a comparative challenge study was performed to evaluate the efficacy of different vaccines against the bacterial pathogen Aeromonas salmonicida...

  20. 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...

  1. Efficiency of advanced wastewater treatment technologies for the reduction of hormonal activity in effluents and connected surface water bodies by means of vitellogenin analyses in rainbow trout (Oncorhynchus mykiss) and brown trout (Salmo trutta f. fario).

    Science.gov (United States)

    Henneberg, Anja; Triebskorn, Rita

    2015-01-01

    Endocrine effects in the aquatic environment are in the focus of scientists and media along with debates on the necessity of further steps in wastewater treatment. In the present study VTG responses were compared to evaluate upgrades at wastewater treatment plants (WWTPs). We investigated several advanced sewage treatment technologies at two WWTPs connected to the Schussen, a tributary of Lake Constance, for the reduction of hormonal activity: (1) a powdered activated charcoal filter at the WWTP Langwiese; and (2) a combination of ozonation, sand filter, and granulated activated carbon filter at the WWTP Eriskirch. Rainbow trout and brown trout were either directly exposed to the effluents in aquaria or cages, or in a bypass system flown through by surface water of the Schussen. As a reference, trout were kept in bypass aquaria at the Argen River, which is less influenced by micropollutants. As a biomarker for estrogenicity, we analyzed the yolk precursor protein vitellogenin in immature rainbow trout and brown trout and in trout larvae (100 days post-fertilization) prior to and after the upgrade with the new technologies. Trout of different ages and species were used to detect differences in their sensitivity. At both bypass stations, larvae of brown trout showed significantly higher vitellogenin levels prior to the upgrade compared to negative control levels. Female brown trout exposed at the bypass station downstream of the WWTP showed decreased vitellogenin levels after the upgrade. In 1-year-old immature trout directly exposed to the respective effluents, no significant effects of the upgrades on vitellogenin levels were found. In general, larger effects were observed in brown trout than in rainbow trout, indicating that they are more sensitive test organisms.

  2. 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...

  3. 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.

  4. Identifying potential virulence determinants in viral haemorrhagic septicaemia virus (VHSV) for rainbow trout

    DEFF Research Database (Denmark)

    Campbell, Scott; Collet, Bertrand; Einer-Jensen, Katja

    2009-01-01

    of an isolate recovered in 2000 from a viral haemorrhagic septicaemia disease episode in a marine rainbow trout farm in Sweden (SE-SVA-1033) was evaluated in juvenile rainbow trout via intraperitoneal injection and immersion challenge alongside 3 isolates recovered from wild-caught marine fish (DK-4p37, DK-5e59...... and UKMLA98/6HE1) suspected of being of low pathogenicity to trout. Mortality data revealed that isolate SE-SVA-1033 caused VHSV-specific mortality in both intraperitoneal and immersion challenges (75.0 and 15.4%, respectively). The remaining Genotype Ib isolates caused significantly lower mortalities using...

  5. 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...

  6. 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.

  7. 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

  8. Sex-specific vitellogenin production in immature rainbow trout

    Energy Technology Data Exchange (ETDEWEB)

    Carlson, D.B.; Williams, D.E.

    1999-10-01

    Many xenobiotics interact with hormone systems of animals, potentially leading to a phenomenon commonly called endocrine disruption. Much attention has focused on steroid hormone systems and corresponding receptor proteins, particularly estrogens. Vitellogenin (Vg) was measured in sexually immature rainbow trout (Oncorhynchus mykiss) exposed to 17{beta}-estradiol (E{sub 2}) in the diet. Mixed-sex populations of trout aged 3, 6, 12, or 18 months were maintained separately and fed E{sub 2} at 0.05 or 2.5 mg/kg for 7d. Females fed E{sub 2} at 0.05 mg/kg consistently produced three- to fourfold greater amounts of Vg than similarly aged males. Age- and sex-matched fish fed E{sub 2} at 2.5 mg/kg produced equivalent amounts of Vg. Sex differences in Vg production were apparent only at a dose of E{sub 2} (0.05 mg/kg) that results in submaximal Vg induction. Their results document the importance of considering the sex of juvenile fish when using Vg production as a marker of xenoestrogen exposure.

  9. 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...

  10. Dependence of myosin-ATPase on structure bound creatine kinase in cardiac myfibrils from rainbow trout and freshwater turtle

    DEFF Research Database (Denmark)

    Haagensen, L.; Jensen, D.H.; Gesser, Hans

    2008-01-01

    The influence of myofibrillar creatine kinase on the myosin-ATPase activity was examined in cardiac ventricular myofibrils isolated from rainbow trout (Oncorhynchus mykiss) and freshwater turtle (Trachemys scripta). The ATPase rate was assessed by recording the rephosphorylation of ADP by the pyr......The influence of myofibrillar creatine kinase on the myosin-ATPase activity was examined in cardiac ventricular myofibrils isolated from rainbow trout (Oncorhynchus mykiss) and freshwater turtle (Trachemys scripta). The ATPase rate was assessed by recording the rephosphorylation of ADP...... by the pyruvate kinase reaction alone or together with the amount of creatine formed, when myofibrillar bound creatine kinase was activated with phosphocreatine. The steady-state concentration of ADP in the solution was varied through the activity of pyruvate kinase added to the solution. For rainbow trout...... myofibrils at a high pyruvate kinase activity, creatine kinase competed for ADP but did not influence the total ATPase activity. When the ADP concentration was elevated within the physiological range by lowering the pyruvate kinase activity, creatine kinase competed efficiently and increased the ATPase...

  11. Effects of hybridization between nonnative Rainbow Trout and native Westslope Cutthroat Trout on fitness-related traits

    Science.gov (United States)

    Drinan, Daniel P.; Webb, Molly A. H.; Naish, Kerry A.; Kalinowski, Steven T.; Boyer, Matthew C.; Steed, Amber C.; Shepard, Bradley B.; Muhlfeld, Clint C.

    2015-01-01

    Hybridization between introduced and native fauna is a risk to native species and may threaten the long-term persistence of numerous taxa. Rainbow Trout Oncorhynchus mykiss has been one of the most widely introduced species around the globe and often hybridizes with native Cutthroat Trout O. clarkii in the Rocky Mountains. Previous work has shown that hybridization negatively affects reproductive success, but identification of the traits contributing to that reduction has been elusive. In this study, we used a combination of field and laboratory techniques to assess how hybridization with Rainbow Trout affects seven traits during several stages of Westslope Cutthroat Trout development: embryonic survival, ova size, ova energy concentration, sperm motility, juvenile weight, juvenile survival, and burst swimming endurance. Rainbow Trout admixture was correlated with an increase in embryonic survival and ova energy concentration but with a decrease in juvenile weight and burst swimming endurance. These correlations differed from previously observed patterns of reproductive success and likely do not explain the declines in reproductive success associated with admixture. Future investigation of additional, unstudied traits and the use of different environments may shed light on the traits responsible for reproductive success in admixed Cutthroat Trout.

  12. 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

  13. 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.

  14. 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...

  15. Factors affecting competitive dominance of rainbow trout over brook trout in southern Appalachian streams: Implications of an individual-based model

    Energy Technology Data Exchange (ETDEWEB)

    Clark, M.E. [Univ. of Tennessee, Knoxville, TN (United States); Rose, K.A. [Oak Ridge National Lab., TN (United States)

    1997-01-01

    We used an individual-based model to examine possible explanations for the dominance of rainbow trout Oncorhynchus mykiss over brook trout Salvelinus fontinalis in southern Appalachian streams. Model simulations were used to quantify the effects on interspecific competition of (1) competitive advantage for feeding sites by rainbow trout, (2) latitudinal differences in stream temperatures, flows, and daylight, (3) year-class failures, (4) lower fecundity of brook trout, and (5) reductions in spawning habitat. The model tracks the daily spawning, growth, and survival of individuals of both species throughout their lifetime in a series of connected stream habitat units (pools, runs, or riffles). Average densities of each species based on 100-year simulations were compared for several levels of each of the five factors and for sympatric and allopatric conditions. Based on model results and empirical information, we conclude that more frequent year-class failures and the lower fecundity of brook trout are both possible and likely explanations for rainbow trout dominance, that warmer temperatures due to latitude and limited spawning habitat are possible but unlikely explanations, and that competitive advantage for feeding sites by rainbow trout is an unlikely explanation. Additional field work should focus on comparative studies of the reproductive success and the early life stage mortalities of brook and rainbow trout among Appalachian streams with varying rainbow trout dominance. 53 refs., 11 figs.

  16. 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).

  17. Rainbow trout fed diets with varying content of marine and plant origin; how does that influence the outcome of experimental infections of the fry with Flavobacterium psychrophilum and Yersinia ruckeri?

    DEFF Research Database (Denmark)

    Madsen, Lone; Ingerslev, Hans-Christian; Boye, Mette

    2014-01-01

    disease caused by Yersinia ruckeri is also an economically important disease which causes problems in rainbow trout fry as well as larger fish. Rainbow trout were fed from first-feeding with five different diets; diet A with marine fish oil (conventional fry diet), diet B (an organic version of A), diet C......Feed for rainbow trout aquaculture has traditionally been based on marine resources such as fish meal and fish oil. Because of a shortage of marine resources as well as the growing production of farmed fish, the feed industry has been forced to partially exchange fish meal protein with proteins...... with rape seed oil (like B but with rape seed oil exchanging marine fish oil), diet C with pea protein (like B but added pea protein) and diet E with rape seed oil and pea protein. When the fry had reached sizes 1.5 g and 4 g, groups of fish from the five diet groups were infected with Flavobacterium...

  18. 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.

  19. 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

  20. 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.

  1. Tissue distribution and elimination of rotenone in rainbow trout

    Science.gov (United States)

    Gingerich, W.H.

    1986-01-01

    The fate of a single i.v. dose (120 μg/kg) of the piscicide [14C]rotenone was evaluated in rainbow trout for periods up to 72 h after dosing. Rotenone was rapidly cleared from the plasma; less than 2% of the dose remained in the plasma compartment after 20 min. The highest concentrations of rotenone residues (% dose/g tissue) were in the hepatobiliary system, bile, intestine, and in heart, lateral line swimming muscle, and posterior kidney; tissues that are highly dependent on oxidative metabolism. Although rotenone activity was present in all cell fractions examined, greater than 40% was associated with the mitochondrial fraction of liver, kidney, and muscle. More than 85% of the activity extracted from these tissues, except the liver, was parent rotenone. Elimination from whole body and major tissue depots conformed to simple first-order kinetics; the estimated half-life from whole body was 68.5 h. Branchial elimination accounted for 5% of the injected dose over a 4-h period, and urinary elimination was less than 2% over a 48-h period. Rotenone was eliminated essentially unchanged across the gills; however, parent rotenone was not found in either urine or bile. More than 80% of the activity in both urine and bile eluted from HPLC chromatographs as a highly polar fraction that was not hydrolyzed by incubation with either β-glucuronidase or sulfatase. The results imply that hepatobiliary excretion is the major route of elimination for rotenone residues in the trout and that metabolism to a more polar form is a prerequisite for elimination in both the bile and the urine

  2. The fibrate drug gemfibrozil disrupts lipoprotein metabolism in rainbow trout

    International Nuclear Information System (INIS)

    Prindiville, John S.; Mennigen, Jan A.; Zamora, Jake M.; Moon, Thomas W.; Weber, Jean-Michel

    2011-01-01

    Gemfibrozil (GEM) is a fibrate drug consistently found in effluents from sewage treatment plants. This study characterizes the pharmacological effects of GEM on the plasma lipoproteins of rainbow trout (Oncorhynchus mykiss). Our goals were to quantify the impact of the drug on: 1) lipid constituents of lipoproteins (phospholipids (PL), triacylglycerol (TAG), and cholesterol), 2) lipoprotein classes (high, low and very low density lipoproteins), and 3) fatty acid composition of lipoproteins. Potential mechanisms of GEM action were investigated by measuring lipoprotein lipase activity (LPL) and the hepatic gene expression of LPL and of the peroxisome proliferator-activated receptor (PPAR) α, β, and γ isoforms. GEM treatment resulted in decreased plasma lipoprotein levels (- 29%) and a reduced size of all lipoprotein classes (lower PL:TAG ratios). However, the increase in HDL-cholesterol elicited by GEM in humans failed to be observed in trout. Therefore, HDL-cholesterol cannot be used to assess the impact of the drug on fish. GEM also modified lipoprotein composition by reducing the abundance of long-chain n-3 fatty acids, thereby potentially reducing the nutritional quality of exposed fish. The relative gene expression of LPL was increased, but the activity of the enzyme was not, and we found no evidence for the activation of PPAR pathways. The depressing effects of GEM on fish lipoproteins demonstrated here may be a concern in view of the widespread presence of fibrates in aquatic environments. Work is needed to test whether exposure to environmental concentrations of these drugs jeopardizes the capacity of fish for reproduction, temperature acclimation or migratory behaviors.

  3. Evaluation of the ability of barley genotypes containing different amounts of ß-glucan to alter growth and disease resistance of rainbow trout Oncorhynchus mykiss.

    Science.gov (United States)

    A feeding trial was performed to screen three barley genotypes containing different levels of '-glucan for their ability to influence growth, immune function, and disease resistance of rainbow trout. Three experimental diets were prepared by substituting each of three barely genotypes containing dif...

  4. Discrimination of bile acids by the rainbow trout olfactory system: Evidence as potential pheromone

    Directory of Open Access Journals (Sweden)

    PERCILIA C GIAQUINTO

    2008-01-01

    Full Text Available Electro-olfactogram recording was used to determine whether the olfactory epithelium of adult rainbow trout is specifically sensitive to bile acids, some of which have been hypothesized to function as pheromones. Of 38 bile acids that had been pre-screened for olfactory activity, 6 were selected. The rainbow trout-specific bile acids, taurocholic acid (TCA, and taurolithocholic acid 3-sulfate (TLS were the most potent compounds tested. TLS had a distinctive dose-response curve. Cross-adaptation experiments demonstrated that sensitivity to bile acids is attributable to at least 3 independent classes of olfactory receptor sites. Our data suggest that bile acids are discriminated by olfaction in rainbow trout, supporting the possibility that these compounds function as pheromones

  5. Characterization of serum amyloid A (SAA) in rainbow trout using a new monoclonal antibody

    DEFF Research Database (Denmark)

    Kania, Per Walter; Chettri, Jiwan Kumar; Buchmann, Kurt

    2014-01-01

    Serum amyloid A (SAA) is an integral part of the innate immune response in mammals and considered to be important during the acute phase response. The present study was undertaken to elucidate the role of SAA protein in the innate immune response of rainbow trout. A monoclonal antibody raised...... against a recombinant peptide of rainbow trout SAA was characterized using Western blot, dot blot, ELISA and immunohistochemistry. SAA association with high density lipoprotein (HDL) complicated band identification in Western blot, but delipidization of the SAA-HDL isolate highly increased the quality...... of reaction in the western blot. Rainbow trout fry (87 days post hatch) infected with Yersinia ruckeri showed a significant up-regulation of the SAA gene at 72 h post infection with an increase until 96 h post infection. Non-significant up-regulations were seen at earlier time points i.e. 4 and 24 h...

  6. Oral and anal vaccination confers full protection against enteric redmouth disease (ERM) in rainbow trout

    DEFF Research Database (Denmark)

    Villumsen, Kasper Rømer; Neumann, Lukas; Otani, Maki

    2014-01-01

    The effect of oral vaccines against bacterial fish diseases has been a topic for debate for decades. Recently both M-like cells and dendritic cells have been discovered in the intestine of rainbow trout. It is therefore likely that antigens reaching the intestine can be taken up and thereby induce...... immunity in orally vaccinated fish. The objective of this project was to investigate whether oral and anal vaccination of rainbow trout induces protection against an experimental waterborne infection with the pathogenic enterobacteria Yersinia ruckeri O1 biotype 1 the causative agent of enteric redmouth...... disease (ERM). Rainbow trout were orally vaccinated with AquaVac ERM Oral (MERCK Animal Health) or an experimental vaccine bacterin of Y. ruckeri O1. Both vaccines were tested with and without a booster vaccination four months post the primary vaccination. Furthermore, two groups of positive controls were...

  7. Molecular crosstalk between a chemical and a biological stressor and consequences on disease manifestation in rainbow trout

    International Nuclear Information System (INIS)

    Burki, Richard; Krasnov, Aleksei; Bettge, Kathrin; Rexroad, Caird E.; Afanasyev, Sergey; Antikainen, Miia; Burkhardt-Holm, Patricia; Wahli, Thomas; Segner, Helmut

    2013-01-01

    The aim of the present study was to examine the molecular and organism reaction of rainbow trout, Oncorhynchus mykiss, to the combined impact of two environmental stressors. The two stressors were the myxozoan parasite, Tetracapsuloides bryosalmonae, which is the etiological agent of proliferative kidney disease (PKD) and a natural stressor to salmonid populations, and 17β-estradiol (E2) as prototype of estrogen-active chemical stressors in the aquatic environment. Both stressors, the parasite and estrogenic contaminants, co-exist in Swiss rivers and are discussed as factors contributing to the decline of Swiss brown trout populations over the last decades. Using a microarray approach contrasting parasite-infected and non-infected rainbow trout at low or high estrogen levels, it was observed that molecular response patterns under joint exposure differed from those to the single stressors. More specifically, three major response patterns were present: (i) expression responses of gene transcripts to one stressor are weakened by the presence of the second stressor; (ii) expression responses of gene transcripts to one stressor are enhanced by the presence of the second stressor; (iii) expression responses of gene transcripts at joint treatment are dominated by one of the two stressors. Organism-level responses to concurrent E2 and parasite treatment – assessed through measuring parasite loads in the fish host and cumulative mortalities of trout – were dominated by the pathogen, with no modulating influence of E2. The findings reveal function- and level-specific responses of rainbow trout to stressor combinations, which are only partly predictable from the response to the single stressors.

  8. Molecular crosstalk between a chemical and a biological stressor and consequences on disease manifestation in rainbow trout

    Energy Technology Data Exchange (ETDEWEB)

    Burki, Richard [Centre for Fish and Wildlife Health, University of Bern, Laenggassstrasse 122, CH-3001 Bern (Switzerland); Krasnov, Aleksei [NOFIMA Marin, Postboks. 5010, 1432As (Norway); Bettge, Kathrin [Centre for Fish and Wildlife Health, University of Bern, Laenggassstrasse 122, CH-3001 Bern (Switzerland); Rexroad, Caird E. [National Center for Cool and Cold Water Aquaculture, USDA-ARS, 11876 Leetown Road, Kearneysville, WV 25430 (United States); Afanasyev, Sergey [Sechenov Institute of Evolutionary Physiology and Biochemistry, M. Toreza av. 44, Peterburg 194223 (Russian Federation); Antikainen, Miia [Institute of Applied Biotechnology, University of Kuopio (Finland); Burkhardt-Holm, Patricia [Man-Society-Environment, University of Basel, Vesalgasse 1, CH-4051 Basel (Switzerland); Wahli, Thomas [Centre for Fish and Wildlife Health, University of Bern, Laenggassstrasse 122, CH-3001 Bern (Switzerland); Segner, Helmut, E-mail: helmut.segner@vetsuisse.unibe.ch [Centre for Fish and Wildlife Health, University of Bern, Laenggassstrasse 122, CH-3001 Bern (Switzerland)

    2013-02-15

    The aim of the present study was to examine the molecular and organism reaction of rainbow trout, Oncorhynchus mykiss, to the combined impact of two environmental stressors. The two stressors were the myxozoan parasite, Tetracapsuloides bryosalmonae, which is the etiological agent of proliferative kidney disease (PKD) and a natural stressor to salmonid populations, and 17{beta}-estradiol (E2) as prototype of estrogen-active chemical stressors in the aquatic environment. Both stressors, the parasite and estrogenic contaminants, co-exist in Swiss rivers and are discussed as factors contributing to the decline of Swiss brown trout populations over the last decades. Using a microarray approach contrasting parasite-infected and non-infected rainbow trout at low or high estrogen levels, it was observed that molecular response patterns under joint exposure differed from those to the single stressors. More specifically, three major response patterns were present: (i) expression responses of gene transcripts to one stressor are weakened by the presence of the second stressor; (ii) expression responses of gene transcripts to one stressor are enhanced by the presence of the second stressor; (iii) expression responses of gene transcripts at joint treatment are dominated by one of the two stressors. Organism-level responses to concurrent E2 and parasite treatment - assessed through measuring parasite loads in the fish host and cumulative mortalities of trout - were dominated by the pathogen, with no modulating influence of E2. The findings reveal function- and level-specific responses of rainbow trout to stressor combinations, which are only partly predictable from the response to the single stressors.

  9. The effect of protein and lipid source in organic feed for (organic) rainbow trout on sensory quality

    DEFF Research Database (Denmark)

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

    2011-01-01

    of vegetable protein. While the lipid sources were fish, linseed, sunflower, rapeseed and grape seed oil. After slaughtering all fish were frozen (-40°C) until the sensory experiment was performed, for which the trout were thawed and stored for 3, 5, 7 and 14 days in ice respectively. The sensory experiment......-life is increased by feeding the fish with vegetable protein compared to fish meal. The conclusion of the experiment therefore was that both dietary vegetable protein and lipid sources can influence on sensory characteristics of trout stored in ice.......The aim of this work was to study which effects protein and lipid source in feed for organic rainbow trout (Oncohynchus mykiss) may have on the sensory quality of the final product after up to 14 days of storage in ice. The protein sources used in the experiment were fishmeal and a mixture...

  10. Effect of stocking sub-yearling Atlantic salmon on the habitat use of sub-yearling rainbow trout

    Science.gov (United States)

    Johnson, James H.

    2016-01-01

    Atlantic salmon (Salmo salar) restoration in the Lake Ontario watershed may depend on the species' ability to compete with naturalized non-native salmonids, including rainbow trout (Oncorhynchus mykiss) in Lake Ontario tributaries. This study examined interspecific habitat associations between sub-yearling Atlantic salmon and rainbow trout as well as the effect of salmon stocking on trout habitat in two streams in the Lake Ontario watershed. In sympatry, Atlantic salmon occupied significantly faster velocities and deeper areas than rainbow trout. However, when examining the habitat use of rainbow trout at all allopatric and sympatric sites in both streams, trout habitat use was more diverse at the sympatric sites with an orientation for increased cover and larger substrate. In Grout Brook, where available habitat remained constant, there was evidence suggesting that trout may have shifted to slower and shallower water in the presence of salmon. The ability of sub-yearling Atlantic salmon to affect a habitat shift in rainbow trout may be due to their larger body size and/or larger pectoral fin size. Future studies examining competitive interactions between these species during their first year of stream residence should consider the size advantage that earlier emerging Atlantic salmon will have over rainbow trout.

  11. 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.

  12. Attenuation of the cortisol response to stress in female rainbow trout chronically exposed to dietary selenomethionine

    Energy Technology Data Exchange (ETDEWEB)

    Wiseman, Steve, E-mail: steve.wiseman@usask.ca [Toxicology Centre, University of Saskatchewan, Saskatoon, SK, S7N 5B3 (Canada); Thomas, Jith K.; McPhee, Landon; Hursky, Olesya; Raine, Jason C. [Toxicology Centre, University of Saskatchewan, Saskatoon, SK, S7N 5B3 (Canada); Pietrock, Michael [Toxicology Centre, University of Saskatchewan, Saskatoon, SK, S7N 5B3 (Canada); Department of Veterinary Biomedical Sciences, University of Saskatchewan, Saskatoon, SK, S7N 5B3 (Canada); Giesy, John P. [Toxicology Centre, University of Saskatchewan, Saskatoon, SK, S7N 5B3 (Canada); Department of Veterinary Biomedical Sciences, University of Saskatchewan, Saskatoon, SK, S7N 5B3 (Canada); Department of Zoology, College of Science, King Saud University, P.O. Box 2455, Riyadh 11451 (Saudi Arabia); Department of Biology and Chemistry, City University of Hong Kong, Kowloon, Hong Kong (Hong Kong); School of Biological Sciences, University of Hong Kong, Hong Kong (Hong Kong); Department of Zoology, Center for Integrative Toxicology, Michigan State University, East Lansing, MI 48824 (United States); State Key Laboratory of Pollution Control and Resource Reuse and School of the Environment, Nanjing University, Nanjing (China); Hecker, Markus [Toxicology Centre, University of Saskatchewan, Saskatoon, SK, S7N 5B3 (Canada); School of Environment and Sustainability, University of Saskatchewan, Saskatoon, SK, S7N 5CB (Canada); Janz, David M. [Toxicology Centre, University of Saskatchewan, Saskatoon, SK, S7N 5B3 (Canada); Department of Veterinary Biomedical Sciences, University of Saskatchewan, Saskatoon, SK, S7N 5B3 (Canada)

    2011-10-15

    Highlights: Trout exposed to Se-Met had greater concentration of cortisol compared to controls. Transcript abundance of mc2r was greater in trout exposed to Se-Met. Trout exposed to Se-Met had a reduced cortisol response to a handling stressor. Cortisone concentration was greater in Se-Met exposed trout post-handling stressor. - Abstract: Selenomethionine (Se-Met) is the major dietary form of selenium (Se). While Se is a required nutrient, it can also influence the physiological stress response because it stimulates greater concentrations of cortisol in blood plasma of exposed fish. However, little is known about the effects of exposure to Se on the ability to cope with a secondary stressor. In the current study, female rainbow trout were exposed to an environmentally relevant dietary concentration (8.47 mg Se/kg dry mass (dm)) of Se-Met for 126 d, after which time fish were subjected to a 3-min handling stressor and sampled at 2 h and 24 h post-stressor exposure. Concentrations of cortisol, cortisone, glucose, and lactate in blood plasma and concentrations of glycogen and triglycerides in liver and muscle were determined. Abundances of transcripts of proteins involved in corticosteroidogenesis were determined using quantitative RT-PCR. Concentrations of cortisol were significantly greater in blood plasma of trout exposed to Se-Met, relative to control trout sampled prior to the handling stressor. A typical response of cortisol to the handling stressor was observed in the control trout. However, trout exposed to Se-Met were unable to mount a cortisol response to the handling stressor. Concentrations of cortisone, the inactive metabolite of cortisol, were significantly greater following the handling stressor in trout exposed to Se-Met. In trout exposed to Se-Met, transcript abundance of melanocortin 2 receptor (mc2r) and peripheral benzodiazepine receptor (pbr) were greater, which is consistent with the conclusion that synthesis of cortisol was greater. However

  13. Attenuation of the cortisol response to stress in female rainbow trout chronically exposed to dietary selenomethionine

    International Nuclear Information System (INIS)

    Wiseman, Steve; Thomas, Jith K.; McPhee, Landon; Hursky, Olesya; Raine, Jason C.; Pietrock, Michael; Giesy, John P.; Hecker, Markus; Janz, David M.

    2011-01-01

    Highlights: Trout exposed to Se-Met had greater concentration of cortisol compared to controls. Transcript abundance of mc2r was greater in trout exposed to Se-Met. Trout exposed to Se-Met had a reduced cortisol response to a handling stressor. Cortisone concentration was greater in Se-Met exposed trout post-handling stressor. - Abstract: Selenomethionine (Se-Met) is the major dietary form of selenium (Se). While Se is a required nutrient, it can also influence the physiological stress response because it stimulates greater concentrations of cortisol in blood plasma of exposed fish. However, little is known about the effects of exposure to Se on the ability to cope with a secondary stressor. In the current study, female rainbow trout were exposed to an environmentally relevant dietary concentration (8.47 mg Se/kg dry mass (dm)) of Se-Met for 126 d, after which time fish were subjected to a 3-min handling stressor and sampled at 2 h and 24 h post-stressor exposure. Concentrations of cortisol, cortisone, glucose, and lactate in blood plasma and concentrations of glycogen and triglycerides in liver and muscle were determined. Abundances of transcripts of proteins involved in corticosteroidogenesis were determined using quantitative RT-PCR. Concentrations of cortisol were significantly greater in blood plasma of trout exposed to Se-Met, relative to control trout sampled prior to the handling stressor. A typical response of cortisol to the handling stressor was observed in the control trout. However, trout exposed to Se-Met were unable to mount a cortisol response to the handling stressor. Concentrations of cortisone, the inactive metabolite of cortisol, were significantly greater following the handling stressor in trout exposed to Se-Met. In trout exposed to Se-Met, transcript abundance of melanocortin 2 receptor (mc2r) and peripheral benzodiazepine receptor (pbr) were greater, which is consistent with the conclusion that synthesis of cortisol was greater. However

  14. Biomarkers study in rainbow trout exposed to industrially contaminated groundwater

    Directory of Open Access Journals (Sweden)

    Nadjet Benchalgo

    2014-03-01

    Full Text Available The spill of liquid industrial waste from chemical and petrochemical industries in Mercier lagoons located 20 km south of Montreal, Quebec, caused a major groundwater contamination by industrial contaminants. The aim of this study was to investigate the toxic effects of Mercier groundwater, following 4 and 14 days of exposure to graded concentrations from three wells at increasing distances 1.2, 2.7 and 5.4 km from the source of contamination. Rainbow trout were examined for several biomarkers of defense [ethoxyresorufin O-deethylase (EROD and gluthatione S-transferase (GST activities] and those of tissue damage [lipid peroxidation (LPO and DNA strand breaks]. The results showed that EROD activity was significantly enhanced in hepatic tissue at 1.2 and 5.4 km, whereas inhibition in activity was observed in group at 2.7 km. Therefore, GST activity was significantly increased at 3.1% concentration for the 2.7 km well. No change in LPO was observed. However, a significant induction of DNA strand breaks in liver was obtained at each distance. In conclusion, the data suggest that the release of these contaminants in groundwater leads to increased biotransformation for coplanar aromatic hydrocarbons and DNA damage in groundwater.

  15. 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

  16. Uptake, disposition, and elimination of acrylamide in rainbow trout

    International Nuclear Information System (INIS)

    Petersen, D.W.; Kleinow, K.M.; Kraska, R.C.; Lech, J.J.

    1985-01-01

    The uptake, disposition, and elimination of [2,3- 14 C]acrylamide was studied in fingerling rainbow trout exposed to 0.388 and 0.710 mg/liter [2,3- 14 C]acrylamide at 12 degrees C under static water conditions for 72 hr. 14 C in carcass and viscera was determined at times ranging from 4 to 72 hr after the beginning of the exposure period and 4 to 96 hr after transfer of the fish to fresh flowing water for the elimination studies. Uptake of 14 C was initially rapid and plateaued after 72 hr of acrylamide exposure. No appreciable bioaccumulation occurred in carcass or viscera at either exposure concentration and 14 C distributed approximately equally to all tissues studied. Elimination of 14 C from carcass and viscera was biphasic with a terminal half-life of approximately 7 days. 14 C elimination was not uniform in all tissues studied with the most rapid elimination occurring in blood and gill and the slowest elimination occurring in muscle and intestine. In addition, 10 to 15% of the initial total 14 C in carcass or viscera was nonextractable and was associated with the protein fraction of the sample at all time points in the depuration period. Approximately 20% of an ip administered dose of [ 14 C]acrylamide was eliminated via the gills, 7% via the urine, and less than 1% via the bile in 2 hr. At least three biliary metabolites were isolated by HPLC

  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. 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.

  19. Effects of turbidity on predation vulnerability of juvenile humpback chub to rainbow and brown trout

    Science.gov (United States)

    Ward, David L.; Morton-Starner, Rylan; Vaage, Benjamin M.

    2016-01-01

    Predation on juvenile native fish by introduced rainbow trout Oncorhynchus mykiss and brown trout Salmo trutta is considered a significant threat to the persistence of endangered humpback chub Gila cypha in the Colorado River in Grand Canyon. Diet studies of rainbow and brown trout in Glen and Grand canyons indicate that these species eat native fish, but impacts are difficult to assess because predation vulnerability is highly variable depending on the physical conditions under which the predation interactions take place. We conducted laboratory experiments to evaluate how short-term predation vulnerability of juvenile humpback chub changes in response to changes in turbidity. In overnight laboratory trials, we exposed hatchery-reared juvenile humpback chub and bonytail Gila elegans (a surrogate for humpback chub) to adult rainbow and brown trout at turbidities ranging from 0 to 1,000 formazin nephlometric units. We found that turbidity as low as 25 formazin nephlometric units significantly reduced predation vulnerability of bonytail to rainbow trout and led to a 36% mean increase in survival (24–60%, 95% CI) compared to trials conducted in clear water. Predation vulnerability of bonytail to brown trout at 25 formazin nephlometric units also decreased with increasing turbidity and resulted in a 25% increase in survival on average (17–32%, 95% CI). Understanding the effects of predation by trout on endangered humpback chub is important when evaluating management options aimed at preservation of native fishes in Grand Canyon National Park. This research suggests that relatively small changes in turbidity may be sufficient to alter predation dynamics of trout on humpback chub in the mainstem Colorado River and that turbidity manipulation may warrant further investigation as a fisheries management tool.

  20. 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.

  1. Circulating levels of cholecystokinin and gastrin-releasing peptide in rainbow trout fed different diets.

    Science.gov (United States)

    Jönsson, Elisabeth; Forsman, Antti; Einarsdottir, Ingibjörg E; Egnér, Barbro; Ruohonen, Kari; Björnsson, Björn Thrandur

    2006-09-01

    Cholecystokinin (CCK) and gastrin-releasing peptide (GRP) are gastrointestinal peptides thought to be important regulators of intake and digestion of food in vertebrates. In this study, pre- and postprandial plasma levels of CCK and GRP were measured in rainbow trout (Oncorhynchus mykiss) by the establishment of homologous radioimmunoassays, and the hormonal levels assessed in relation to dietary lipid:protein ratio and food intake. Fish were acclimated to either a high protein/low lipid diet (HP/LL diet; 14.1% lipids) or a normal protein/high lipid diet (NP/HL diet; 31.4% lipids). On three consecutive sampling days, radio-dense lead-glass beads were included in the diets for assessment of feed intake. Fish were terminally sampled for blood and stomach contents prior to feeding at time 0, and at 0.3, 1, 2, 4, 6, and 24 h after feeding. There was a postprandial elevation of plasma CCK levels, which was most evident after 4 and 6 h. Fish fed the NP/HL diet had higher plasma CCK levels compared with those fed the HP/LL diet. Plasma CCK levels were not affected by the amount of food ingested. GRP levels in plasma were not influenced by sampling time, diet, or feed intake. The results indicate that the endocrine release of gastrointestinal CCK is increased during feeding and may be further influenced by the dietary lipid:protein ratio in rainbow trout. Plasma GRP levels, on the other hand, appear not to be influenced by feeding or diet composition.

  2. Successional change in the Lake Superior fish community: population trends in ciscoes, rainbow smelt, and lake trout, 1958-2008

    Science.gov (United States)

    Gorman, Owen T.

    2012-01-01

    The Lake Superior fish community underwent massive changes in the second half of the 20th century. Those changes are largely reflected in changes in abundance of the adults of principal prey species, the ciscoes (Coregonus spp.), the invasive rainbow smelt (Osmerus mordax), and the principal predator, lake trout (Salvelinus namaycush). To better understand changes in species abundances, a comprehensive series of gillnet and bottom trawl data collected from 1958 to 2008 were examined. In the late 1950s/early 1960s, smelt abundance was at its maximum, wild lake trout was at its minimum, and an abundance of hatchery lake trout was increasing rapidly. The bloater (Coregonus hoyi) was the prevalent cisco in the lake; abundance was more than 300% greater than the next most abundant cisco, shortjaw cisco (C. zenithicus), followed by kiyi (C. kiyi) and lake cisco (C. artedi). By the mid-1960s, abundance of hatchery lake trout was nearing maximum, smelt abundance was beginning to decline, and abundances of all ciscoes declined, but especially that of shortjaw cisco and kiyi. By the late 1970s, recovery of wild lake trout stocks was well underway and abundances of hatchery lake trout and smelt were declining and the ciscoes were reaching their nadir. During 1980–1990, the fish community underwent a dramatic shift in organization and structure. The rapid increase in abundance of wild lake trout, concurrent with a rapid decline in hatchery lake trout, signaled the impending recovery. Rainbow smelt abundance dropped precipitously and within four years, lake cisco and bloater populations rebounded on the heels of a series of strong recruitment events. Kiyi populations showed signs of recovery by 1989, and shortjaw by 2000, though well below historic maximum abundances. High abundance of adult smelt prior to 1980 appears to be the only factor linked to recruitment failure in the ciscoes. Life history traits of the cisco species were examined to better understand their different

  3. 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...

  4. Review of potential interactions between stocked rainbow trout and listed Snake River sockeye salmon in Pettit Lake Idaho

    Energy Technology Data Exchange (ETDEWEB)

    Teuscher, D.

    1996-05-01

    The objective of this study was to determine if hatchery rainbow trout compete with or prey on juvenile Snake River sockeye salmon Oncorhynchus nerka in Pettit Lake, Idaho. In 1995, a total of 8,570 age-0 sockeye and 4,000 hatchery rainbow trout were released in Pettit Lake. After releasing the fish, gillnets were set in the pelagic and littoral zones to collected diet and spatial distribution data. Interactions were assessed monthly from June 1995 through March 1996. Competition for food was discounted based on extremely low diet overlap results observed throughout the sample period. Conversely, predation interactions were more significant. A total of 119 rainbow trout stomachs were analyzed, two contained O. nerka. The predation was limited to one sample period, but when extrapolated to the whole rainbow trout populations results in significant losses. Total consumption of O. nerka by rainbow trout ranged from an estimated 10 to 23% of initial stocking numbers. Predation results contradict earlier findings that stocked rainbow trout do not prey on wild kokanee or sockeye in the Sawtooth Lakes. The contradiction may be explained by a combination of poorly adapted hatchery sockeye and a littoral release site that forced spatial overlap that was not occurring in the wild populations. Releasing sockeye in the pelagic zone may have reduced or eliminated predation losses to rainbow trout.

  5. Review of potential interactions between stocked rainbow trout and listed Snake River sockeye salmon in Pettit Lake Idaho

    International Nuclear Information System (INIS)

    Teuscher, D.

    1996-01-01

    The objective of this study was to determine if hatchery rainbow trout compete with or prey on juvenile Snake River sockeye salmon Oncorhynchus nerka in Pettit Lake, Idaho. In 1995, a total of 8,570 age-0 sockeye and 4,000 hatchery rainbow trout were released in Pettit Lake. After releasing the fish, gillnets were set in the pelagic and littoral zones to collected diet and spatial distribution data. Interactions were assessed monthly from June 1995 through March 1996. Competition for food was discounted based on extremely low diet overlap results observed throughout the sample period. Conversely, predation interactions were more significant. A total of 119 rainbow trout stomachs were analyzed, two contained O. nerka. The predation was limited to one sample period, but when extrapolated to the whole rainbow trout populations results in significant losses. Total consumption of O. nerka by rainbow trout ranged from an estimated 10 to 23% of initial stocking numbers. Predation results contradict earlier findings that stocked rainbow trout do not prey on wild kokanee or sockeye in the Sawtooth Lakes. The contradiction may be explained by a combination of poorly adapted hatchery sockeye and a littoral release site that forced spatial overlap that was not occurring in the wild populations. Releasing sockeye in the pelagic zone may have reduced or eliminated predation losses to rainbow trout

  6. 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...

  7. 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.

  8. Thymocyte plasma membrane of the rainbow trout, Salmo gairdneri: Associated immunoglobulin and heteroantigens

    Science.gov (United States)

    Warr, G.W.; DeLuca, D.; Anderson, D.P.

    1983-01-01

    1. Thymic lymphocytes of the rainbow trout, S. gairdneri were disrupted and a plasma membrane containing fraction isolated by differential and buoyant density centrifugation.2. Radioiodine introduced into the membrane by the lactoperoxidase catalyzed reaction and immunoglobulin (identified by radioimmunoassay with monoclonal antibody) both copurified in the plasma membrane fraction.3. Rabbit antibody raised to the plasma membrane fraction showed a strong reaction with trout lymphocytes in immunofluorescence, was mitogenic for trout lymphocytes, and recognized lymphocyte membrane heteroantigens of molecular weight > 70,000 in the thymus and 45,000–95,000 in the head kidney.

  9. Assessing the potential for rainbow trout reproduction in tributaries of the Mountain Fork River below Broken Bow Dam, southeastern Oklahoma

    Science.gov (United States)

    Long, James M.; Starks, Trevor A.; Farling, Tyler; Bastarache, Robert

    2016-01-01

    Stocked trout (Salmonidae) in reservoir tailwater systems in the Southern United States have been shown to use tributary streams for spawning and rearing. The lower Mountain Fork of the Little River below Broken Bow Dam is one of two year-round tailwater trout fisheries in Oklahoma, and the only one with evidence of reproduction by stocked rainbow trout (Oncorhynchus mykiss). Whether stocked trout use tributaries in this system for spawning is unknown. Furthermore, an

  10. 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.

  11. Regulation of energy metabolism during social interactions in rainbow trout: a role for AMP-activated protein kinase.

    Science.gov (United States)

    Gilmour, K M; Craig, P M; Dhillon, R S; Lau, G Y; Richards, J G

    2017-11-01

    Rainbow trout ( Oncorhynchus mykiss ) confined in pairs form social hierarchies in which subordinate fish typically experience fasting and high circulating cortisol levels, resulting in low growth rates. The present study investigated the role of AMP-activated protein kinase (AMPK) in mediating metabolic adjustments associated with social status in rainbow trout. After 3 days of social interaction, liver AMPK activity was significantly higher in subordinate than dominant or sham (fish handled in the same fashion as paired fish but held individually) trout. Elevated liver AMPK activity in subordinate fish likely reflected a significantly higher ratio of phosphorylated AMPK (phospho-AMPK) to total AMPK protein, which was accompanied by significantly higher AMPKα 1 relative mRNA abundance. Liver ATP and creatine phosphate concentrations in subordinate fish also were elevated, perhaps as a result of AMPK activity. Sham fish that were fasted for 3 days exhibited effects parallel to those of subordinate fish, suggesting that low food intake was an important trigger of elevated AMPK activity in subordinate fish. Effects on white muscle appeared to be influenced by the physical activity associated with social interaction. Overall, muscle AMPK activity was significantly higher in dominant and subordinate than sham fish. The ratio of phospho-AMPK to total AMPK protein in muscle was highest in subordinate fish, while muscle AMPKα 1 relative mRNA abundance was elevated by social dominance. Muscle ATP and creatine phosphate concentrations were high in dominant and subordinate fish at 6 h of interaction and decreased significantly thereafter. Collectively, the findings of the present study support a role for AMPK in mediating liver and white muscle metabolic adjustments associated with social hierarchy formation in rainbow trout. Copyright © 2017 the American Physiological Society.

  12. Unsteady turbulent boundary layers in swimming rainbow trout.

    Science.gov (United States)

    Yanase, Kazutaka; Saarenrinne, Pentti

    2015-05-01

    The boundary layers of rainbow trout, Oncorhynchus mykiss, swimming at 1.02±0.09 L s(-1) (mean±s.d., N=4), were measured by the particle image velocimetry (PIV) technique at a Reynolds number of 4×10(5). The boundary layer profile showed unsteadiness, oscillating above and beneath the classical logarithmic law of the wall with body motion. Across the entire surface regions that were measured, local Reynolds numbers based on momentum thickness, which is the distance that is perpendicular to the fish surface through which the boundary layer momentum flows at free-stream velocity, were greater than the critical value of 320 for the laminar-to-turbulent transition. The skin friction was dampened on the convex surface while the surface was moving towards a free-stream flow and increased on the concave surface while retreating. These observations contradict the result of a previous study using different species swimming by different methods. Boundary layer compression accompanied by an increase in local skin friction was not observed. Thus, the overall results may not support absolutely the Bone-Lighthill boundary layer thinning hypothesis that the undulatory motions of swimming fish cause a large increase in their friction drag because of the compression of the boundary layer. In some cases, marginal flow separation occurred on the convex surface in the relatively anterior surface region, but the separated flow reattached to the fish surface immediately downstream. Therefore, we believe that a severe impact due to induced drag components (i.e. pressure drag) on the swimming performance, an inevitable consequence of flow separation, was avoided. © 2015. Published by The Company of Biologists Ltd.

  13. 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...

  14. 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...

  15. 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...

  16. A first generation integrated physical and genetic map of the rainbow trout genome

    Science.gov (United States)

    The rainbow trout physical map was previously constructed from DNA fingerprinting of 192,096 BAC clones using the 4-color high-information content fingerprinting (HICF) method. The clones were assembled into physical map contigs using the finger-printing contig (FPC) program. The map is composed of ...

  17. 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...

  18. Prospecting genomic regions associated with Columnaris disease in two commercially important rainbow trout breeding populations

    Science.gov (United States)

    Flavbacterium Columnare, the causative agent of Columnaris disease (CD), is distributed around the world in fresh water sources, infecting freshwater finfish species. Recently it has been identified as an emerging problem for the rainbow trout aquaculture industry in the US. Two live-attenuated va...

  19. 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...

  20. 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...

  1. The microflora of rainbow trout intestine : a comparison of traditional and molecular identification

    DEFF Research Database (Denmark)

    Spanggaard, Bettina; Huber, I.; Nielsen, J.

    2000-01-01

    The culturability of the intestinal microflora of 48 rainbow trout was detected by comparing direct microscopic counts (4',6-diamidino-2-phenylindole, DAPI) with plate counts (tryptone soya agar, TSA). In general, a high percentage (average 50%) of the microflora could be cultured. The counts...

  2. Global 3D imaging of Yersinia ruckeri bacterin uptake in rainbow trout fry

    DEFF Research Database (Denmark)

    Otani, Maki; Villumsen, Kasper Rømer; Koppang, Erling Olaf

    2015-01-01

    Yersinia ruckeri is the causative agent of enteric redmouth disease (ERM) in rainbow trout, and the first commercially available fish vaccine was an immersion vaccine against ERM consisting of Y. ruckeri bacterin. The ERM immersion vaccine has been successfully used in aquaculture farming of salm...

  3. 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.

  4. 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...

  5. Infectious Pancreatic Necrosis (IPN), a New Threat of Cultured Rainbow Trout in Iran

    DEFF Research Database (Denmark)

    Ghasemi, Mohaddes; Olesen, Niels Jørgen; Skall, Helle Frank

    province, north of Iran, reported unusually high losses of reared rainbow trout fry with average weight of 560 mg. same mortality were reported from 4 other farms in fryes under 1 gram weight in 2010. Clinical signs included darkening, exophthalmia, distended abdomen, fecal cast and a spiral swimming...

  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. Determining Vaccination Frequency in Farmed Rainbow Trout Using Vibrio anguillarum O1 Specific Serum Antibody Measurements

    DEFF Research Database (Denmark)

    Holten-Andersen, Lars; Dalsgaard, Inger; Nylén, Jørgen

    2012-01-01

    Background Despite vaccination with a commercial vaccine with a documented protective effect against Vibrio anguillarum O1 disease outbreaks caused by this bacterium have been registered among rainbow trout at Danish fish farms. The present study examined specific serum antibody levels as a valid...

  8. Yersiniosis outbreak in rainbow trout at fish farm in Oromia Regional ...

    African Journals Online (AJOL)

    This study showed the importance of stress induced by higher temperature and poor water quality associated with infestations by Trichodina species as predisposing factors to bacterial diseases in intensive fish farming practices. Key words: bacterial culture, histopathology, rainbow trout, Yersinia ruckeri, Trichodina species ...

  9. 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...

  10. 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...

  11. 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...

  12. 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

  13. 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...

  14. Long term anoxia in rainbow trout investigated by 2-DE and MS/MS

    DEFF Research Database (Denmark)

    Wulff, Tune; Jessen, Flemming; Roepstorff, P.

    2008-01-01

    Twenty-four hours of N-2 induced anoxia induced global perturbations on protein expression in rainbow trout hypodermal fibroblasts cell line. Anoxia was obtained by depleting the medium of O-2 by flushing with N-2, and protein changes were studied by 2-DE coupled with MS providing quantitative...

  15. Characterization of elements of the kallikrein-kinin system in rainbow trout (Salmo gairdneri)

    International Nuclear Information System (INIS)

    Lipke, D.W.

    1988-01-01

    Elements of kallikrein-kinin system (KKS) are found in anamniotic vertebrates, however, research has failed to substantiate the presence of a KKS in these animals. This research was conducted to verify the presence of elements of the KKS in rainbow trout. Trout branchial angiotensin-converting enzyme (ACE, kininase II) was similar to mammalian ACE in many physical, chemical and kinetic parameters. Angiotensin-converting enzyme-like activity (ACELA) was also demonstrated in the most primitive vertebrates. ACELA was consistently found in vertebrate respiratory tissues and was prevalent in salt and water exchanging organs. 3 H-bradykinin, perfused through the trout gill was not metabolized, as demonstrated by high voltage paper electrophoresis. However, trout gills extracted and retained approximately 40% of the 3 H-bradykinin perfused into the branchial vasculature. Gill tissue homogenates metabolized both 3 H-bradykinin and the vasoactive substance produced by incubating trout plasma with glandular kallikrein

  16. Single nucleotide polymorphism discovery in rainbow trout by deep sequencing of a reduced representation library

    Directory of Open Access Journals (Sweden)

    Salem Mohamed

    2009-11-01

    Full Text Available Abstract Background To enhance capabilities for genomic analyses in rainbow trout, such as genomic selection, a large suite of polymorphic markers that are amenable to high-throughput genotyping protocols must be identified. Expressed Sequence Tags (ESTs have been used for single nucleotide polymorphism (SNP discovery in salmonids. In those strategies, the salmonid semi-tetraploid genomes often led to assemblies of paralogous sequences and therefore resulted in a high rate of false positive SNP identification. Sequencing genomic DNA using primers identified from ESTs proved to be an effective but time consuming methodology of SNP identification in rainbow trout, therefore not suitable for high throughput SNP discovery. In this study, we employed a high-throughput strategy that used pyrosequencing technology to generate data from a reduced representation library constructed with genomic DNA pooled from 96 unrelated rainbow trout that represent the National Center for Cool and Cold Water Aquaculture (NCCCWA broodstock population. Results The reduced representation library consisted of 440 bp fragments resulting from complete digestion with the restriction enzyme HaeIII; sequencing produced 2,000,000 reads providing an average 6 fold coverage of the estimated 150,000 unique genomic restriction fragments (300,000 fragment ends. Three independent data analyses identified 22,022 to 47,128 putative SNPs on 13,140 to 24,627 independent contigs. A set of 384 putative SNPs, randomly selected from the sets produced by the three analyses were genotyped on individual fish to determine the validation rate of putative SNPs among analyses, distinguish apparent SNPs that actually represent paralogous loci in the tetraploid genome, examine Mendelian segregation, and place the validated SNPs on the rainbow trout linkage map. Approximately 48% (183 of the putative SNPs were validated; 167 markers were successfully incorporated into the rainbow trout linkage map. In

  17. Single nucleotide polymorphism discovery in rainbow trout by deep sequencing of a reduced representation library.

    Science.gov (United States)

    Sánchez, Cecilia Castaño; Smith, Timothy P L; Wiedmann, Ralph T; Vallejo, Roger L; Salem, Mohamed; Yao, Jianbo; Rexroad, Caird E

    2009-11-25

    To enhance capabilities for genomic analyses in rainbow trout, such as genomic selection, a large suite of polymorphic markers that are amenable to high-throughput genotyping protocols must be identified. Expressed Sequence Tags (ESTs) have been used for single nucleotide polymorphism (SNP) discovery in salmonids. In those strategies, the salmonid semi-tetraploid genomes often led to assemblies of paralogous sequences and therefore resulted in a high rate of false positive SNP identification. Sequencing genomic DNA using primers identified from ESTs proved to be an effective but time consuming methodology of SNP identification in rainbow trout, therefore not suitable for high throughput SNP discovery. In this study, we employed a high-throughput strategy that used pyrosequencing technology to generate data from a reduced representation library constructed with genomic DNA pooled from 96 unrelated rainbow trout that represent the National Center for Cool and Cold Water Aquaculture (NCCCWA) broodstock population. The reduced representation library consisted of 440 bp fragments resulting from complete digestion with the restriction enzyme HaeIII; sequencing produced 2,000,000 reads providing an average 6 fold coverage of the estimated 150,000 unique genomic restriction fragments (300,000 fragment ends). Three independent data analyses identified 22,022 to 47,128 putative SNPs on 13,140 to 24,627 independent contigs. A set of 384 putative SNPs, randomly selected from the sets produced by the three analyses were genotyped on individual fish to determine the validation rate of putative SNPs among analyses, distinguish apparent SNPs that actually represent paralogous loci in the tetraploid genome, examine Mendelian segregation, and place the validated SNPs on the rainbow trout linkage map. Approximately 48% (183) of the putative SNPs were validated; 167 markers were successfully incorporated into the rainbow trout linkage map. In addition, 2% of the sequences from the

  18. Persistent effects of wildfire and debris flows on the invertebrate prey base of rainbow trout in Idaho streams

    Science.gov (United States)

    Rosenberger, A.E.; Dunham, J.B.; Buffington, J.M.; Wipfli, M.S.

    2011-01-01

    Wildfire and debris flows are important physical and ecological drivers in headwater streams of western North America. Past research has primarily examined short-term effects of these disturbances; less is known about longer-term impacts. We investigated wildfire effects on the invertebrate prey base for drift-feeding rainbow trout (Oncorhynchus mykiss, Walbaum) in Idaho headwater streams a decade after wildfire. Three stream types with different disturbance histories were examined: 1) unburned, 2) burned, and 3) burned followed by debris flows that reset channel morphology and riparian vegetation. The quantity of macroinvertebrate drift (biomass density) was more variable within than among disturbance categories. Average body weight and taxonomic richness of drift were significantly related to water temperature and influenced by disturbance history. During the autumn sampling period, the amount of terrestrial insects in rainbow trout diets varied with disturbance history and the amount of overhead canopy along the stream banks. Results indicate that there are detectable changes to macroinvertebrate drift and trout diet a decade after wildfire, and that these responses are better correlated with specific characteristics of the stream (water temperature, canopy cover) than with broad disturbance classes.

  19. Effects of bromacil, diuron, glyphosate, and sulfometuron-methyl on periphyton assemblages and rainbow trout : final report.

    Science.gov (United States)

    2003-01-01

    This study documents the testing of several common herbicides used by the Oregon Department of Transportation in vegetation management. The project assessed the short- and long-term effects of Roundup, Krovar and Oust on periphyton and rainbow trout....

  20. Evidence of major genes affecting stress response in rainbow trout using Bayesian methods of complex segregation analysis

    DEFF Research Database (Denmark)

    Vallejo, R L; Rexroad III, C E; Silverstein, J T

    2009-01-01

    As a first step toward the genetic mapping of QTL affecting stress response variation in rainbow trout, we performed complex segregation analyses (CSA) fitting mixed inheritance models of plasma cortisol by using Bayesian methods in large full-sib families of rainbow trout. To date, no studies have...... been conducted to determine the mode of inheritance of stress response as measured by plasma cortisol response when using a crowding stress paradigm and CSA in rainbow trout. The main objective of this study was to determine the mode of inheritance of plasma cortisol after a crowding stress....... The results from fitting mixed inheritance models with Bayesian CSA suggest that 1 or more major genes with dominant cortisol-decreasing alleles and small additive genetic effects of a large number of independent genes likely underlie the genetic variation of plasma cortisol in the rainbow trout families...

  1. 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...

  2. Postprandial regulation of hepatic microRNAs predicted to target the insulin pathway in rainbow trout.

    Directory of Open Access Journals (Sweden)

    Jan A Mennigen

    Full Text Available Rainbow trout are carnivorous fish and poor metabolizers of carbohydrates, which established this species as a model organism to study the comparative physiology of insulin. Following the recent characterisation of key roles of several miRNAs in the insulin action on hepatic intermediary metabolism in mammalian models, we investigated the hypothesis that hepatic miRNA expression is postprandially regulated in the rainbow trout and temporally coordinated in the context of insulin-mediated regulation of metabolic gene expression in the liver. To address this hypothesis, we used a time-course experiment in which rainbow trout were fed a commercial diet after short-term fasting. We investigated hepatic miRNA expression, activation of the insulin pathway, and insulin regulated metabolic target genes at several time points. Several miRNAs which negatively regulate hepatic insulin signaling in mammalian model organisms were transiently increased 4 h after the meal, consistent with a potential role in acute postprandial negative feed-back regulation of the insulin pathway and attenuation of gluconeogenic gene expression. We equally observed a transient increase in omy- miRNA-33 and omy-miRNA-122b 4 h after feeding, whose homologues have potent lipogenic roles in the liver of mammalian model systems. A concurrent increase in the activity of the hepatic insulin signaling pathway and the expression of lipogenic genes (srebp1c, fas, acly was equally observed, while lipolytic gene expression (cpt1a and cpt1b decreased significantly 4 h after the meal. This suggests lipogenic roles of omy-miRNA-33 and omy-miRNA-122b may be conserved between rainbow trout and mammals and that these miRNAs may furthermore contribute to acute postprandial regulation of de novo hepatic lipid synthesis in rainbow trout. These findings provide a framework for future research of miRNA regulation of hepatic metabolism in trout and will help to further elucidate the metabolic

  3. Evaluation of glutamic acid and glycine as sources of nonessential amino acids for lake trout (Salvelinus namaycush) and rainbow trout (Salmo gairdnerii)

    Science.gov (United States)

    Hughes, S.G.

    1985-01-01

    1. A semi-purified test diet which contained either glutamic acid or glycine as the major source of nonessential amino acids (NEAA) was fed to lake and rainbow trout.2. Trout fed the diet containing glutamic acid consistently showed better growth and feed conversion efficiencies than those fed the diets containing glycine.3. The data indicate that these trout utilize glutamic acid more efficiently than glycine when no other major sources of NEAA are present.

  4. Effects of soluble immunostimulants on mucosal immune responses in rainbow trout immersion-vaccinated against Yersinia ruckeri

    DEFF Research Database (Denmark)

    Skov, Jakob; Chettri, Jiwan Kumar; Jaafar, Rzgar M.

    2018-01-01

    elevate the immune response and the present work elucidates how ERM immersion vaccination of trout in combination with exposure to soluble adjuvants, Montanide™ IMS 1312 VG PR and β-glucan, affects immune reactions. The former adjuvant, when used alone, induced a slightly increased protection (not......Immersion vaccination of rainbow trout against Yersinia ruckeri infection is an established method to prevent enteric red mouth disease (ERM) but the effect is inferior to injection vaccination and the duration of protection is limited to less than six months. Adjuvants in vaccines may in general...... weeks no vaccine induced reaction was seen and after challenge with bacteria mainly unvaccinated fish responded. Adjuvants used in combination with immersion vaccine clearly influences immune reactions and may improve duration and protection but further potency tests should be performed....

  5. [Specific problems posed by carbohydrate utilization in the rainbow trout].

    Science.gov (United States)

    Bergot, F

    1979-01-01

    Carbohydrate incorporation in trout diets arises problems both at digestive and metabolic levels. Digestive utilization of carbohydrate closely depends on their molecular weight. In addition, in the case of complex carbohydrates (starches), different factors such as the level of incorporation, the amount consumed and the physical state of starch influence the digestibility. The measurement of digestibility in itself is confronted with methodological difficulties. The way the feces are collected can affect the digestion coefficient. Dietary carbohydrates actually serve as a source of energy. Nevertheless, above a certain level in the diet, intolerance phenomena may appear. The question that arises now is to establish the optimal part that carbohydrates can take in the metabolizable energy of a given diet.

  6. Link between lipid metabolism and voluntary food intake in rainbow trout fed coconut oil rich in medium-chain TAG

    NARCIS (Netherlands)

    Figueiredo-Silva, A.C.; Kaushik, S.; Terrier, F.; Schrama, J.W.; Médale, F.; Geurden, I.

    2012-01-01

    We examined the long-term effect of feeding coconut oil (CO; rich in lauric acid, C12) on voluntary food intake and nutrient utilisation in rainbow trout (Oncorhynchus mykiss), with particular attention to the metabolic use (storage or oxidation) of ingested medium-chain TAG. Trout were fed for 15

  7. 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 ...

  8. 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...

  9. Description age-3 brood rainbow trout bred in the conditions of the industral fish farm "Sloboda Banyliv"

    Directory of Open Access Journals (Sweden)

    P. Mendryshora

    2017-06-01

    Full Text Available Purpose. To analyze the results of cultivation and give fish-breeding and biological characteristics of age-3 brood rainbow trout grown using industrial technology in the conditions of the trout farm "Sloboda Banyliv." Methodology. Fish cultivation was carried in tank conditions of the trout farm "Sloboda Banyliv". The material for the study were age-3 brood rainbow trout obtained from eggs of the fall-spawning form of rainbow trout. Cultivation was carried out in a 216 m2 tank, stocking density of 255 fish/m2, using standard trout culture methods. Statistical analysis of the material was performed in Microsoft Office Excel (2003. Analysis of the variables was performed in the system of absolute values. The analysis criteria were their mean values mean deviations (M±m, standard error (σ, variability coefficient (Cv. Fish were fed with specialized feed manufactured by “BioMar” (Denmark with a high protein content (more than 40%. Findings. Based on the performed selective-breeding works aimed at creating brood stocks of rainbow trout, it was found that brood fish reared in the industrial conditions of the fish farm “Sloboda Banyliv”, despite instable culture conditions, were characterized by a moderate growth rate and had high values of productive and reproductive features. Mean weight of age-3 rainbow trout females was 1282.5 g, fecundity — 3.48 thousand eggs. Mean weight of produced eggs was 239.17 g, while individual parameters were 70.4 mg for the weight and 4.58 mm for the diameter. Originality. For the first time a study aimed at the formation of brood stocks of rainbow trout with analysis of phenotypic and productive features in the conditions of a fish farm with instable temperature and water regimes has been conducted. Practical value. The results of the performed work will allow selecting and forming a brood stock with high values of productive and reproductive features.

  10. Ecotoxicity of Lake Druksiai waters assessed by biotesting with rainbow trout spawn and larvae

    International Nuclear Information System (INIS)

    Kazlauskiene, N.; Cepuliene, Z.

    1998-01-01

    The toxicity of Lake Druksiai was assessed by testing with spawn and larvae of rainbow trout (Oncorhynchus mykiss). We sampled Ignalina NPP waste waters of various biotopes of the lake. Larvae of trout were found to be more sensitive to wastewaters than spawn. The hatching stage was one of the most sensitive stages in ontogenesis. Our data showed that the wastewater of Ignalina NPP was the most toxic, however waters of some biotopes of the lake were also toxic. That suggested that toxicants discharged into cooling reservoirs with NPP wastewater might affect test-organisms, disturbing their development and growth. The observed effects were irreversible and caused death. (author)

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

    DEFF Research Database (Denmark)

    Baatrup, E

    1989-01-01

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

  12. 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...

  13. 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.

  14. Immune Response in Head Kidney of Rainbow Trout Fry Following Stress and Infection with Flavobacterium Psychrophilum

    DEFF Research Database (Denmark)

    Henriksen, Maya Maria Mihályi; Kania, P. W.; Madsen, Lone

    response in rainbow trout against F. psychrophilum in order to create preventive measures against RTFS. A limited number of studies have been carried out so far and have relied on samples from either naturally infected or injection-challenged fish. The use of naturally infected fish introduces many...... before pathogen exposure to elevate mortality. The model was used to examine the immune response to infection in rainbow trout fry (≈1 g); both with and without preceding H2O2 treatment. Samples from the head kidney were taken before pathogen exposure and 4 hours, 48 hours, 125 hours and 192 hours after...... exposure. The regulation of several immune relevant genes was examined and the relative bacterial load was assessed. Although it is not determined how H2O2 increases mortality, it is assumed to be due to stress. Exposure to H2O2 prior to infection altered the regulation of several genes, and several...

  15. Can VHS virus bypass the protective immunity induced by DNA vaccination in rainbow trout?

    DEFF Research Database (Denmark)

    Sepúlveda, Dagoberto; Lorenzen, Niels

    2016-01-01

    DNA vaccines encoding viral glycoproteins have been very successful for induction of protective immunity against diseases caused by rhabdoviruses in cultured fish species. However, the vaccine concept is based on a single viral gene and since RNA viruses are known to possess high variability...... and adaptation capacity, this work aimed at evaluating whether viral haemorrhagic septicaemia virus (VHSV), an RNA virus and member of Rhabdoviridae family, was able to evade the protective immune response induced by the DNA vaccination of rainbow trout. The experiments comprised repeated passages of a highly...... pathogenic VHSV isolate in a fish cell line in the presence of neutralizing fish serum (in vitro approach), and in rainbow trout immunized with the VHS DNA vaccine (in vivo approach). For the in vitro approach, the virus collected from the last passage (passaged virus) was as sensitive as the parental virus...

  16. A New Furunculosis Challenge Method for Evaluation of Vaccine Efficacy in Rainbow Trout

    DEFF Research Database (Denmark)

    Marana, Moonika Haahr; Chettri, Jiwan Kumar; Skov, Jakob

    2016-01-01

    Experimental infection of fish for vaccine efficacy studies is associated with several limitations. Administration of live bacteria with the purpose of causing disease in fish can be performed by co-habitation, immersion or injection. We have developed a new Aeromonas salmonicida challenge method...... for rainbow trout and have applied it for evaluation of furunculosis vaccine efficacy. The method reveals development of systemic immunity in fish as live bacteria are introduced in the tail fin epidermis distant from the vaccine injection site (peritoneal cavity). This method seeks to mimic natural infection...... in fish farms where tail biting and therefore bacterial expo- sure to tail fin ulcers is widespread. By use of a multi-needle device ten epidermal perforations were introduced in the dorsal part of the tail fin of anaesthetized rainbow trout (vaccinated or naive). Subsequently 100 μL (3.4 × 108 colony-forming...

  17. Use of DNA vaccination for determination of onset of adaptive immunity in rainbow trout fry

    DEFF Research Database (Denmark)

    Rasmussen, Jesper Skou; Lorenzen, Ellen; Kjær, Torben Egil

    2013-01-01

    ). The fish were challenged by immersion at different times post vaccination. Protective immunity was induced in both sizes of fish, but whereas clear-cut specific protection was evident in the fish vaccinated at 0.5g, the results suggested that the protection in the fish vaccinated at 0.25 g was mainly due......Vaccine producers often recommend a minimum size of 5g for vaccination of rainbow trout, but implementation of prophylactic vaccination in smaller sized fish would be an advantage for several infectious diseases. To implement a cost efficient vaccination strategy, it is important to know...... the duration and nature of the protective immunity induced by the vaccines in the fish. The present work aimed at determination of the smallest size at which specific immunity could be induced in rainbow trout fry by DNA vaccination against viral haemorrhagic septicaemia (VHS). Earlier experiments revealed...

  18. A novel challenge method with aeromonas salmonicida in rainbow trout for evaluation of furunculosis vaccines

    DEFF Research Database (Denmark)

    Marana, M. H.; Skov, J.; Chettri, J. K.

    2015-01-01

    Challenge methods used to induce furunculosis in rainbow trout when testing the potency of vaccines may include exposure to Aeromonas salmonicida by intraperitoneal injection, cohabitation or bath immersion. Intraperitoneal injection is effective but will not reflect systemic immunity because...... inflammatory cells at the vaccine injection site may combat injected bacteria fast. The cohabitation and bath immersion methods both mimic the natural infection route but are less effective in inducing the disease. We have tested a new challenge method mimicking that rainbow trout in fish farms might...... to be efficient in inducing a more natural disease progression in fish and a stable mortality. The method could differentiate efficacies of different vaccines with regard to adjuvant formulations and content of antigen....

  19. 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....

  20. Effects of adjuvant Montanide™ ISA 763 A VG in rainbow trout injection vaccinated against Yersinia ruckeri

    DEFF Research Database (Denmark)

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

    2015-01-01

    Enteric redmouth disease (ERM) caused by the fish pathogen Yersinia ruckeri is a major threat to freshwater production of rainbow trout (Oncorhynchus mykiss) throughout all life stages. Injection vaccination of rainbow trout against Y. ruckeri infection has been shown to confer better protection...... fish (NonVac), 2) fish injected with a commercial vaccine (AquaVac(®) Relera™) (ComVac), 3) fish injected with an experimental vaccine (ExpVac), 4) fish injected with an experimental vaccine + adjuvant (ExpVacAdj) and 5) fish injected with adjuvant alone (Adj). Injection of the experimental vaccine...... of the adjuvant as the challenge produced 100% mortality in the NonVac group, 60% mortality in both of ComVac and Adj groups and only 13 and 2.5% mortalities in the ExpVac and the ExpVacAdj groups, respectively....

  1. Interference of an ERM-vaccine with a VHS-DNA vaccine in rainbow trout

    DEFF Research Database (Denmark)

    Lorenzen, Ellen; Einer-Jensen, Katja; Rasmussen, Jesper Skou

    Simultaneous vaccination of fish against several diseases is often desirable in order to minimise cost and handling of the fish. Intramuscular DNA-vaccination of rainbow trout against viral haemorrhagic septicaemia virus (VHSV) has proved to provide very good protection. However, preliminary...... results showed that intraperitoneal injection of a commercial vaccine against Enteric Redmouth Disease (ERM) based on formalin-killed bacteria in oil adjuvant immediately followed by intramuscular injection of an experimental DNA-vaccine against VHSV, decreased the protective effect of the DNA......-vaccine against challenge with VHSV 11 weeks post vaccination (pv). This experiment was performed with rainbow trout of 30 g injected with 0.5 g VHS-DNA vaccine. The experiment was later repeated with smaller fish (2.5g) and using two different doses of DNA-vaccine, 1 g and 0.05 g. Both doses provided good...

  2. 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.

  3. 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...

  4. Genomic Prediction Accuracy for Resistance Against Piscirickettsia salmonis in Farmed Rainbow Trout

    Directory of Open Access Journals (Sweden)

    Grazyella M. Yoshida

    2018-02-01

    Full Text Available Salmonid rickettsial syndrome (SRS, caused by the intracellular bacterium Piscirickettsia salmonis, is one of the main diseases affecting rainbow trout (Oncorhynchus mykiss farming. To accelerate genetic progress, genomic selection methods can be used as an effective approach to control the disease. The aims of this study were: (i to compare the accuracy of estimated breeding values using pedigree-based best linear unbiased prediction (PBLUP with genomic BLUP (GBLUP, single-step GBLUP (ssGBLUP, Bayes C, and Bayesian Lasso (LASSO; and (ii to test the accuracy of genomic prediction and PBLUP using different marker densities (0.5, 3, 10, 20, and 27 K for resistance against P. salmonis in rainbow trout. Phenotypes were recorded as number of days to death (DD and binary survival (BS from 2416 fish challenged with P. salmonis. A total of 1934 fish were genotyped using a 57 K single-nucleotide polymorphism (SNP array. All genomic prediction methods achieved higher accuracies than PBLUP. The relative increase in accuracy for different genomic models ranged from 28 to 41% for both DD and BS at 27 K SNP. Between different genomic models, the highest relative increase in accuracy was obtained with Bayes C (∼40%, where 3 K SNP was enough to achieve a similar accuracy to that of the 27 K SNP for both traits. For resistance against P. salmonis in rainbow trout, we showed that genomic predictions using GBLUP, ssGBLUP, Bayes C, and LASSO can increase accuracy compared with PBLUP. Moreover, it is possible to use relatively low-density SNP panels for genomic prediction without compromising accuracy predictions for resistance against P. salmonis in rainbow trout.

  5. YERSINIA RUCKERI INFECT RAINBOW TROUT THROUGH THE GILLS DEMONSTRATED BY A THREE-DIMENSIONAL IMAGING ANALYSIS

    DEFF Research Database (Denmark)

    Otani, Maki; Raida, Martin Kristian

    2013-01-01

    -dimensional (3D) imaging of small tissues. Rainbow trout were infected with Yersinia ruckeri O1 biotype 1 (1 x 109 cells/ml) for 1 hour at 18°C, and significant mortality were observed post infection. Three fish were sampled at different time points and fixed in 4% paraformaldehyde for OPT, or 10% formalin...... is a strong tool for 3D visualization of the bacteria infection routes in the host tissues....

  6. A Computational Model of the Rainbow Trout Hypothalamus-Pituitary-Ovary-Liver Axis.

    Directory of Open Access Journals (Sweden)

    Kendall Gillies

    2016-04-01

    Full Text Available Reproduction in fishes and other vertebrates represents the timely coordination of many endocrine factors that culminate in the production of mature, viable gametes. In recent years there has been rapid growth in understanding fish reproductive biology, which has been motivated in part by recognition of the potential effects that climate change, habitat destruction and contaminant exposure can have on natural and cultured fish populations. New approaches to understanding the impacts of these stressors are being developed that require a systems biology approach with more biologically accurate and detailed mathematical models. We have developed a multi-scale mathematical model of the female rainbow trout hypothalamus-pituitary-ovary-liver axis to use as a tool to help understand the functioning of the system and for extrapolation of laboratory findings of stressor impacts on specific components of the axis. The model describes the essential endocrine components of the female rainbow trout reproductive axis. The model also describes the stage specific growth of maturing oocytes within the ovary and permits the presence of sub-populations of oocytes at different stages of development. Model formulation and parametrization was largely based on previously published in vivo and in vitro data in rainbow trout and new data on the synthesis of gonadotropins in the pituitary. Model predictions were validated against several previously published data sets for annual changes in gonadotropins and estradiol in rainbow trout. Estimates of select model parameters can be obtained from in vitro assays using either quantitative (direct estimation of rate constants or qualitative (relative change from control values approaches. This is an important aspect of mathematical models as in vitro, cell-based assays are expected to provide the bulk of experimental data for future risk assessments and will require quantitative physiological models to extrapolate across

  7. Role of the GH-IGF-1 system in Atlantic salmon and rainbow trout postsmolts at elevated water temperature.

    Science.gov (United States)

    Hevrøy, Ernst M; Tipsmark, Christian K; Remø, Sofie C; Hansen, Tom; Fukuda, Miki; Torgersen, Thomas; Vikeså, Vibeke; Olsvik, Pål A; Waagbø, Rune; Shimizu, Munetaka

    2015-10-01

    A comparative experiment with Atlantic salmon (Salmo salar) and rainbow trout (Oncorhynchus mykiss) postsmolts was conducted over 35 days to provide insight into how growth, respiration, energy metabolism and the growth hormone (GH) and insulin-like growth factor 1 (IGF-1) system are regulated at elevated sea temperatures. Rainbow trout grew better than Atlantic salmon, and did not show reduced growth at 19 °C. Rainbow trout kept at 19 °C had increased blood hemoglobin concentration compared to rainbow trout kept at 13 °C, while salmon did not show the same hemoglobin response due to increased temperature. Both species showed reduced length growth and decreased muscle glycogen stores at 19 °C. Circulating IGF-1 concentration was higher in rainbow trout than in Atlantic salmon, but was not affected by temperature in either species. Plasma IGF-binding protein 1b (IGFBP-1b) concentration was reduced in Atlantic salmon reared at 19 °C after 15 days but increased in rainbow trout at 19 °C after 35 days. The igfbp1b mRNA level in liver showed a positive correlation to plasma concentrations of glucose and IGFBP-1b, suggesting involvement of this binding protein in carbohydrate metabolism at 19 °C. At this temperature muscle igfbp1a mRNA was down-regulated in both species. The muscle expression of this binding protein correlated negatively with muscle igf1 and length growth. The plasma IGFBP-1b concentration and igfbp1b and igfbp1a expression suggests reduced muscle igf1 signaling at elevated temperature leading to glucose allostasis, and that time course is species specific due to higher thermal tolerance in rainbow trout. Copyright © 2015 Elsevier Inc. All rights reserved.

  8. Consideration on detection of irradiated rainbow trout by ESR method and 2-alkylcyclobutanone analysis

    International Nuclear Information System (INIS)

    Tanabe, Hiroko; Goto, Michiko

    2002-01-01

    Relative ESR strength of rib, backbone and opercular bone from irradiated culture rainbow trout was direct proportional to dose between 0.56kGy and 5.7kGy. Relative ESR strength of rib was higher than that of backbone. Although only 5mg of otolith was obtained from one rainbow trout, bone density of otolith is so high that relative ESR strength of otolith showed about 20-fold higher value than that of rib. In GCMS-SIM analysis of RCB, radiolytic compounds of lipid of fish meat, the amount of both DCB and TCB formed, estimated from ion concentrations of m/z98, were direct proportional to dose between 1.1kGy and 11.1kGy. Neither DCB nor TCB was detected in unirradiated sample. The ratio of amount of DCB formed to amount of TCB formed was nearly 4.4, which is the ratio of palmitic acid content to stearic acid content in rainbow trout, denoted in Standard Tables of Food Composition in Japan; Lipid composition of Foods. Finally, we propose to use detection of radiolytic compound, RCB, and measurement of ESR of high-density bone together for reliable identification of irradiated fish. (author)

  9. Occurrence, size, and tag retention of sneaker male hatchery rainbow trout

    Science.gov (United States)

    Isely, J.J.; Grabowski, T.B.

    2004-01-01

    One alternative reproductive tactic involving early-maturing, cryptic males is referred to as "sneaking." Although sneakers tend to be easily detectable upon close inspection, little is known about the proportion of a fish population consisting of sneakers. We examined 15,400 age-1 rainbow trout Oncorhynchus mykiss in a hatchery. Total length (mm), wet weight (g), and sex (sneaker male or unknown) were recorded for each fish. We also individually tagged each sneaker male with soft visual implant alphanumeric (VIalpha) tags that were sequentially numbered and held the fish for 25 d before inspection. Sneakers constituted 2.8% of the hatchery rainbow trout population and were smaller in total length and weight than typical rainbow trout of the same age. Retention of the VIalpha tags in sneakers was 58.9%, significantly lower than has been reported under similar circumstances. We found that sneaker males may contribute substantially to hatchery populations. Reduced tag retention in sneakers may bias studies evaluating the effect of hatchery fish on wild populations. We believe that hatchery-produced sneaker males have the potential to contribute importantly to the genetic composition of wild populations.

  10. Studies on the metabolism of astaxanthin in the rainbow trout (Salmo gairdneri)

    International Nuclear Information System (INIS)

    Al-Khalifah, A.S.

    1986-01-01

    Racemic astaxanthin was fed to rainbow trout (Salmo gairdneri) for 2, 4, and 6 weeks. The fish showed a bright pink coloration of the skin and flesh; the highest amount of astaxanthin was found in the skin of fish fed the test diet for six weeks. Lutein, 3-epilutein, and zeaxanthin were also detected in the flesh and skin; it was concluded that astaxanthin was converted to zeaxanthin in the skin. The mean vitamin A content of the liver was determined; the ratio of vitamin A 1 :vitamin A 2 was approximately 1:3. Retinol and 3,4-dehydroretinol were extracted from the intestine of rainbow trout low in vitamin A, after force feeding with astaxanthin using a feeding tube. Antibiotic-treated fish had no marked difference in vitamin A content compared with a control group that received no antibiotic. This proves that astaxanthin was converted to vitamin A in fish depleted of vitamin A, that microorganisms were not involved in the conversion, and that conversion occurred in the intestine. An in vitro study using 3 H 3S, 3S'-astaxanthin incubated with duodenal and ileal segments of the intestine provided HLPC and radioisotope data, which showed that rainbow trout were able to bioconvert astaxanthin to vitamin A

  11. 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

  12. 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.

  13. Exposure of rainbow trout milt to mercury and cadmium alters sperm motility parameters and reproductive success

    International Nuclear Information System (INIS)

    Dietrich, Grzegorz J.; Dietrich, Mariola; Kowalski, R.K.; Dobosz, Stefan; Karol, Halina; Demianowicz, Wieslaw; Glogowski, Jan

    2010-01-01

    In the current work, seminal plasma was used for the first time as an incubation medium for monitoring short-time exposure effects of sublethal concentrations of mercury and cadmium ions on rainbow trout sperm. Sperm motility parameters (CASA) and hatching rates were used as gamete quality markers. Additionally live/dead sperm viability test and comet assay of DNA fragmentation were performed. We demonstrated that computer-assisted sperm motility analysis (CASA) may serve as a predictor of reproductive success, when milt contaminated with heavy metals is used. Results presented in this study demonstrate that mercury ions altered sperm motility characteristics at 1-10 mg Hg 2+ /l and 10 mg Cd 2+ /l and hatching rates at 10 mg Hg 2+ /l and 10 mg Cd 2+ /l after 4 h of exposure. Although mercury ions affected sperm motility parameters immediately after dilution with milt as well as at 4 h of exposure, no differences in sperm motility parameters were found between intact and mercury-treated milt after 24 h of exposure. Our results suggest that rainbow trout seminal plasma has a protective role against the toxic effects of mercury ions of rainbow trout sperm motility.

  14. 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.

  15. 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.

  16. 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.

  17. 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.

  18. 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.

  19. Consideration on detection of irradiated rainbow trout by ESR method and 2-alkylcyclobutanone analysis

    International Nuclear Information System (INIS)

    Tanabe, H.; Goto, M.

    2002-01-01

    R elative ESR strength of rib, backbone and opercular bone from irradiated culture rainbow trout was direct proportional to dose between 0.56kGy and 5.7kGy. Relative ESR strength of rib was higher than that of backbone. Although only 5mg of otolith was obtained from one rainbow trout, bone density of otolith is so high that relative ESR strength of otolith showed about 20-fold higher value than that of rib. In GCMS-SIM analysis of RGB, radiolytic compounds of lipid of fish meat, the amount of both DCB and TCB formed, estimated from ion concentrations of m/z98, were direct proportional to dose between 1.1kGy and 11.1kGy. Neither DCB nor TCB was detected in unirradiated sample. The ratio of amount of DCB formed to amount of TCB formed was nearly 4.4, which is the ratio of palmitic acid content to stearic acid content in rainbow trout, denoted in Standard Tables of Food Composition in Japan; Lipid composition of Foods. Finally, we propose to use detection of radiolytic compound, RCB, and measurement of ESR of high-density bone together for reliable identification of irradiated fish

  20. 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

  1. 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

  2. The fatty acid profile of rainbow trout liver cells modulates their tolerance to methylmercury and cadmium

    International Nuclear Information System (INIS)

    Ferain, Aline; Bonnineau, Chloé; Neefs, Ineke; Rees, Jean François; Larondelle, Yvan; Schamphelaere, Karel A.C.De; Debier, Cathy

    2016-01-01

    Highlights: • The phospholipid composition of rainbow trout liver cells was successfully changed. • Cell phospholipids influenced methylmercury (MeHg) and cadmium (Cd) toxicity. • Cells enriched in 18:3n-3, 20:5n-3 or 22:5n-6 were more resistant to MeHg and Cd. • Cell enrichment in 22:6n-3 increased resistance to Cd but not MeHg. - Abstract: The polyunsaturated fatty acid (PUFA) composition of fish tissues, which generally reflects that of the diet, affects various cellular properties such as membrane structure and fluidity, energy metabolism and susceptibility to oxidative stress. Since these cellular parameters can play an important role in the cellular response to organic and inorganic pollutants, a variation of the PUFA supply might modify the toxicity induced by such xenobiotics. In this work, we investigated whether the cellular fatty acid profile has an impact on the in vitro cell sensitivity to two environmental pollutants: methylmercury and cadmium. Firstly, the fatty acid composition of the rainbow trout liver cell line RTL-W1 was modified by enriching the growth medium with either alpha-linolenic acid (ALA, 18:3n-3), eicosapentaenoic acid (EPA, 20:5n-3), docosahexaenoic acid (DHA, 22:6n-3), linoleic acid (LA, 18:2n-6), arachidonic acid (AA, 20:4n-6) or docosapentaenoic acid (DPA, 22:5n-6). These modified cells and their control (no PUFA enrichment) were then challenged for 24 h with increasing concentrations of methylmercury or cadmium. We observed that (i) the phospholipid composition of the RTL-W1 cells was profoundly modulated by changing the PUFA content of the growth medium: major modifications were a high incorporation of the supplemented PUFA in the cellular phospholipids, the appearance of direct elongation and desaturation metabolites in the cellular phospholipids as well as a change in the gross phospholipid composition (PUFA and monounsaturated fatty acid (MUFA) levels and n-3/n-6 ratio); (ii) ALA, EPA and DPA enrichment significantly

  3. The fatty acid profile of rainbow trout liver cells modulates their tolerance to methylmercury and cadmium

    Energy Technology Data Exchange (ETDEWEB)

    Ferain, Aline, E-mail: aline.ferain@uclouvain.be [Institute of Life Sciences, Université catholique de Louvain, Place Croix du Sud 2/L7.05.08, B-1348 Louvain-la-Neuve (Belgium); Bonnineau, Chloé [Institute of Life Sciences, Université catholique de Louvain, Place Croix du Sud 2/L7.05.08, B-1348 Louvain-la-Neuve (Belgium); Irstea, UR MALY, Centre de Lyon-Villeurbanne, rue de la Doua 5/32108, F-69616 Villeurbanne (France); Neefs, Ineke; Rees, Jean François; Larondelle, Yvan [Institute of Life Sciences, Université catholique de Louvain, Place Croix du Sud 2/L7.05.08, B-1348 Louvain-la-Neuve (Belgium); Schamphelaere, Karel A.C.De [Laboratory of Environmental Toxicology and Aquatic Ecology, Environmental Toxicology Unit, Ghent University, J. Plateaustraat 22, B-9000 Ghent (Belgium); Debier, Cathy [Institute of Life Sciences, Université catholique de Louvain, Place Croix du Sud 2/L7.05.08, B-1348 Louvain-la-Neuve (Belgium)

    2016-08-15

    Highlights: • The phospholipid composition of rainbow trout liver cells was successfully changed. • Cell phospholipids influenced methylmercury (MeHg) and cadmium (Cd) toxicity. • Cells enriched in 18:3n-3, 20:5n-3 or 22:5n-6 were more resistant to MeHg and Cd. • Cell enrichment in 22:6n-3 increased resistance to Cd but not MeHg. - Abstract: The polyunsaturated fatty acid (PUFA) composition of fish tissues, which generally reflects that of the diet, affects various cellular properties such as membrane structure and fluidity, energy metabolism and susceptibility to oxidative stress. Since these cellular parameters can play an important role in the cellular response to organic and inorganic pollutants, a variation of the PUFA supply might modify the toxicity induced by such xenobiotics. In this work, we investigated whether the cellular fatty acid profile has an impact on the in vitro cell sensitivity to two environmental pollutants: methylmercury and cadmium. Firstly, the fatty acid composition of the rainbow trout liver cell line RTL-W1 was modified by enriching the growth medium with either alpha-linolenic acid (ALA, 18:3n-3), eicosapentaenoic acid (EPA, 20:5n-3), docosahexaenoic acid (DHA, 22:6n-3), linoleic acid (LA, 18:2n-6), arachidonic acid (AA, 20:4n-6) or docosapentaenoic acid (DPA, 22:5n-6). These modified cells and their control (no PUFA enrichment) were then challenged for 24 h with increasing concentrations of methylmercury or cadmium. We observed that (i) the phospholipid composition of the RTL-W1 cells was profoundly modulated by changing the PUFA content of the growth medium: major modifications were a high incorporation of the supplemented PUFA in the cellular phospholipids, the appearance of direct elongation and desaturation metabolites in the cellular phospholipids as well as a change in the gross phospholipid composition (PUFA and monounsaturated fatty acid (MUFA) levels and n-3/n-6 ratio); (ii) ALA, EPA and DPA enrichment significantly

  4. Temporal genetic monitoring of hybridization between native westslope cutthroat trout and introduced rainbow trout in the Stehekin River, Washington

    Science.gov (United States)

    Ostberg, Carl O.; Chase, Dorothy M.

    2012-01-01

    Introgressive hybridization with introduced rainbow trout (RBT) (Oncorhynchus mykiss) has led to the loss of native cutthroat trout species (O. clarkii) throughout their range, creating conservation concerns. Monitoring temporal hybridization trends provides resource managers with a tool for determining population status and information for establishing conservation goals for native cutthroat trout. In this study, we re-sampled six locations in 2010 within the Stehekin River watershed, North Cascades National Park, which were originally sampled between 1999 and 2003. We used genetic markers to monitor changes in hybridization levels between sampling periods in the native westslope cutthroat trout (WCT) (O. c. lewisi) stemming from past RBT introductions. Additionally, two new locations from the lower Stehekin drainage were added to the baseline data. We found that the frequency of WCT, RBT, and their hybrids was not significantly different between monitoring periods, but that RBT allele frequencies decreased in two locations and increased in one location. We also found a consistent, substantial reduction in the frequency of RBT alleles over the monitoring period in the Stehekin River upstream of Bridge Creek (SR3) compared to the Stehekin River downstream of Bridge Creek (SR1 -2) and within lower Bridge Creek (BR1) although these three locations are confined to a small geographic area (approximately 5 km). Ecological and/or evolutionary processes likely restrict the dispersal of RBT alleles in the Stehekin River upstream of Bridge Creek.

  5. 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

  6. 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...

  7. 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...

  8. 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.

  9. 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....

  10. 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.

  11. 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.

  12. Estimation of waste generated by the production of rainbow trout in Lake Tota, Colombia

    Directory of Open Access Journals (Sweden)

    Nixon Hernán Torres-Barrera

    2017-05-01

    Full Text Available In this study, the total waste from the production of rainbow trout, Oncorhynchus mykiss ( Wa l b a u m (Salmoniformes: Salmonidae in Lake Tota freshwater ecosystem, located in the Department of Boyacá, Colombia, and its potential impact on the lake was estimated. This economic activity has been carried out intensively since 2005 using submerged cages in the lake. With data obtained from the National Authority for Aquaculture and Fisheries (Aunap, the Autonomous Regional Corporation of Boyacá (Corpoboyacá, and the Chamber of Commerce of Sogamoso, fish farmers, their geographical location on the lake, production by these farms were identified, and with this information the amount of waste produced, including the amounts of nitrogen and phosphorus generated in this process was calculated. The results indicate that the lake is polluted due to intensive trout production. It is recommended to improve or modify trout production methods that will minimize water pollution.

  13. A first generation BAC-based physical map of the rainbow trout genome

    Directory of Open Access Journals (Sweden)

    Thorgaard Gary H

    2009-10-01

    Full Text Available Abstract Background Rainbow trout (Oncorhynchus mykiss are the most-widely cultivated cold freshwater fish in the world and an important model species for many research areas. Coupling great interest in this species as a research model with the need for genetic improvement of aquaculture production efficiency traits justifies the continued development of genomics research resources. Many quantitative trait loci (QTL have been identified for production and life-history traits in rainbow trout. A bacterial artificial chromosome (BAC physical map is needed to facilitate fine mapping of QTL and the selection of positional candidate genes for incorporation in marker-assisted selection (MAS for improving rainbow trout aquaculture production. This resource will also facilitate efforts to obtain and assemble a whole-genome reference sequence for this species. Results The physical map was constructed from DNA fingerprinting of 192,096 BAC clones using the 4-color high-information content fingerprinting (HICF method. The clones were assembled into physical map contigs using the finger-printing contig (FPC program. The map is composed of 4,173 contigs and 9,379 singletons. The total number of unique fingerprinting fragments (consensus bands in contigs is 1,185,157, which corresponds to an estimated physical length of 2.0 Gb. The map assembly was validated by 1 comparison with probe hybridization results and agarose gel fingerprinting contigs; and 2 anchoring large contigs to the microsatellite-based genetic linkage map. Conclusion The production and validation of the first BAC physical map of the rainbow trout genome is described in this paper. We are currently integrating this map with the NCCCWA genetic map using more than 200 microsatellites isolated from BAC end sequences and by identifying BACs that harbor more than 300 previously mapped markers. The availability of an integrated physical and genetic map will enable detailed comparative genome

  14. Identification of steelhead and resident rainbow trout progeny in the Deschutes River, Oregon, revealed with otolith microchemistry

    Science.gov (United States)

    Zimmerman, C.E.; Reeves, G.H.

    2002-01-01

    Comparisons of strontium:calcium (Sr:Ca) ratios in otolith primordia and freshwater growth regions were used to identify the progeny of steelhead Oncorhynchus mykiss (anadromous rainbow trout) and resident rainbow trout in the Deschutes River, Oregon. We cultured progeny of known adult steelhead and resident rainbow trout to confirm the relationship between Sr:Ca ratios in otolith primordia and the life history of the maternal parent. The mean (??SD) Sr:Ca ratio was significantly higher in the otolith primordia of the progeny of steelhead (0.001461 ?? 0.00029; n = 100) than in those of the progeny of resident rainbow trout (0.000829 ?? 0.000012; n = 100). We used comparisons of Sr:Ca ratios in the primordia and first-summer growth regions of otoliths to determine the maternal origin of unknown O. mykiss juveniles (n = 272) collected from rearing habitats within the main-stem Deschutes River and tributary rearing habitats and thus to ascertain the relative proportion of each life history morph in each rearing habitat. Resident rainbow trout fry dominated the bi-monthly samples collected from main-stem rearing habitats between May and November 1995. Steelhead fry dominated samples collected from below waterfalls on two tributaries in 1996 and 1998.

  15. Molecular detection of Aeromonas hydrophila in the aquarium gold fish and cultured rainbow trout in Chaharmahal va Bakhtiary province

    Directory of Open Access Journals (Sweden)

    firouz Fadaeifard

    2014-05-01

    Full Text Available Aeromonas hydrophilia   is the etiologic agent of motile aeromonas septicaemia, one of the most important bacterial diseases of fresh and marine water fishes. The aim of the present study was detection of A. hydrophilia in the aquarium goldfish and cultured rainbow trout in Chaharmahal va Bakhtiary province.  In this study 50 goldfish from aquarium fish shops and 60 rainbow trouts suspected of having the disease from 6 farms (10 fish in each farm were randomly collected. The average weight in goldfish and rainbow trout samples were 3-5 g and 10-20 g, respectively. Sampling was performed from kidney and liver, and inoculated into blood agar and incubated at 22°C for 24 hours. Pure colonies which are grown on the mediums were tested by catalase, oxidase and gram staining, then those of gram-negative, catalase and oxidase positive were diagnosed, and cultured on Shotts-Rimler medium (as selective medium for A. hydrophila. These mediums were incubated at 22 °C for 24-48 h. The typical colonies were tested by using oligonucleotide primers of lip gene by PCR method. In light of molecular analysis of all specimens, 9 and 6 isolates from rainbow trout and gold fishes were identified as A. hydrophila respectively. Due to the detection of A. hydrophila in both cultured rainbow trout and aquarium goldfish, the bacteria can lead to septicemia with mortality if the health management principles are not observed in fish farming.

  16. Hybridization between Yellowstone cutthroat trout and rainbow trout alters the expression of muscle growth-related genes and their relationships with growth patterns

    Science.gov (United States)

    Ostberg, Carl O.; Chase, Dorothy M.; Hauser, Lorenz

    2015-01-01

    Hybridization creates novel gene combinations that may generate important evolutionary novelty, but may also reduce existing adaptation by interrupting inherent biological processes, such as genotype-environment interactions. Hybridization often causes substantial change in patterns of gene expression, which, in turn, may cause phenotypic change. Rainbow trout (Oncorhynchus mykiss) and cutthroat trout (O. clarkii) produce viable hybrids in the wild, and introgressive hybridization with introduced rainbow trout is a major conservation concern for native cutthroat trout. The two species differ in body shape, which is likely an evolutionary adaptation to their native environments, and their hybrids tend to show intermediate morphology. The characterization of gene expression patterns may provide insights on the genetic basis of hybrid and parental morphologies, as well as on the ecological performance of hybrids in the wild. Here, we evaluated the expression of eight growth-related genes (MSTN-1a, MSTN-1b, MyoD1a, MyoD1b, MRF-4, IGF-1, IGF-2, and CAST-L) and the relationship of these genes with growth traits (length, weight, and condition factor) in six line crosses: both parental species, both reciprocal F1 hybrids, and both first-generation backcrosses (F1 x rainbow trout and F1 x cutthroat trout). Four of these genes were differentially expressed among rainbow, cutthroat, and their hybrids. Transcript abundance was significantly correlated with growth traits across the parent species, but not across hybrids. Our findings suggest that rainbow and cutthroat trout exhibit differences in muscle growth regulation, that transcriptional networks may be modified by hybridization, and that hybridization disrupts intrinsic relationships between gene expression and growth patterns that may be functionally important for phenotypic adaptations.

  17. 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.

  18. 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.

  19. Gene expression and pathologic alterations in juvenile rainbow trout due to chronic dietary TCDD exposure

    International Nuclear Information System (INIS)

    Liu, Qing; Rise, Matthew L.; Spitsbergen, Jan M.; Hori, Tiago S.; Mieritz, Mark; Geis, Steven; McGraw, Joseph E.; Goetz, Giles; Larson, Jeremy; Hutz, Reinhold J.; Carvan, Michael J.

    2013-01-01

    Highlights: •First report of the effects of dietary TCDD in juvenile trout smaller than 20 g. •TCDD uptake was estimated using published models and confirmed by GC. •First report of dietary TCDD-induced lesions in nasal epithelium in any species. •Several useful biomarkers are identified from microarray-based transcriptomics analysis. -- Abstract: The goal of this project was to use functional genomic methods to identify molecular biomarkers as indicators of the impact of TCDD exposure in rainbow trout. Specifically, we investigated the effects of chronic dietary TCDD exposure on whole juvenile rainbow trout global gene expression associated with histopathological analysis. Juvenile rainbow trout were fed Biodiet starter with TCDD added at 0, 0.1, 1, 10 and 100 ppb (ng TCDD/g food), and fish were sampled from each group at 7, 14, 28 and 42 days after initiation of feeding. 100 ppb TCDD caused 100% mortality at 39 days. Fish fed with 100 ppb TCDD food had TCDD accumulation of 47.37 ppb (ng TCDD/g fish) in whole fish at 28 days. Histological analysis from TCDD-treated trout sampled from 28 and 42 days revealed that obvious lesions were found in skin, oropharynx, liver, gas bladder, intestine, pancreas, nose and kidney. In addition, TCDD caused anemia in peripheral blood, decreases in abdominal fat, increases of remodeling of fin rays, edema in pericardium and retrobulbar hemorrhage in the 100 ppb TCDD-treated rainbow trout compared to the control group at 28 days. Dose- and time-dependent global gene expression analyses were performed using the cGRASP 16,000 (16K) cDNA microarray. TCDD-responsive whole body transcripts identified in the microarray experiments have putative functions involved in various biological processes including growth, cell proliferation, metabolic process, and immune system processes. Nine microarray-identified genes were selected for QPCR validation. CYP1A3 and CYP1A1 were common up-regulated genes and HBB1 was a common down

  20. Gene expression and pathologic alterations in juvenile rainbow trout due to chronic dietary TCDD exposure

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Qing [Department of Biological Sciences, University of Wisconsin-Milwaukee, Lapham Hall, 3209 N. Maryland Ave., Milwaukee, WI 53211 (United States); School of Freshwater Sciences, University of Wisconsin-Milwaukee, 600 E Greenfield Ave, Milwaukee, WI 53204 (United States); Rise, Matthew L. [Ocean Sciences Centre, Memorial University of Newfoundland, 1 Marine Lab Road, St. John' s, NL, A1C 5S7 (Canada); Spitsbergen, Jan M. [Department of Microbiology, Oregon State University, 220 Nash Hall, Corvallis, OR 97331 (United States); Hori, Tiago S. [Ocean Sciences Centre, Memorial University of Newfoundland, 1 Marine Lab Road, St. John' s, NL, A1C 5S7 (Canada); Mieritz, Mark; Geis, Steven [Wisconsin State Laboratory of Hygiene, 465 Henry Mall, Madison, WI 53706 (United States); McGraw, Joseph E. [School of Pharmacy, Concordia University Wisconsin, 12800 North Lake Shore Drive, Mequon, WI 53097 (United States); Goetz, Giles [School of Aquatic and Fishery Sciences, University of Washington, 1122 Northeast Boat Street, Seattle, WA 98195 (United States); Larson, Jeremy; Hutz, Reinhold J. [Department of Biological Sciences, University of Wisconsin-Milwaukee, Lapham Hall, 3209 N. Maryland Ave., Milwaukee, WI 53211 (United States); Carvan, Michael J., E-mail: carvanmj@uwm.edu [Department of Biological Sciences, University of Wisconsin-Milwaukee, Lapham Hall, 3209 N. Maryland Ave., Milwaukee, WI 53211 (United States); School of Freshwater Sciences, University of Wisconsin-Milwaukee, 600 E Greenfield Ave, Milwaukee, WI 53204 (United States)

    2013-09-15

    Highlights: •First report of the effects of dietary TCDD in juvenile trout smaller than 20 g. •TCDD uptake was estimated using published models and confirmed by GC. •First report of dietary TCDD-induced lesions in nasal epithelium in any species. •Several useful biomarkers are identified from microarray-based transcriptomics analysis. -- Abstract: The goal of this project was to use functional genomic methods to identify molecular biomarkers as indicators of the impact of TCDD exposure in rainbow trout. Specifically, we investigated the effects of chronic dietary TCDD exposure on whole juvenile rainbow trout global gene expression associated with histopathological analysis. Juvenile rainbow trout were fed Biodiet starter with TCDD added at 0, 0.1, 1, 10 and 100 ppb (ng TCDD/g food), and fish were sampled from each group at 7, 14, 28 and 42 days after initiation of feeding. 100 ppb TCDD caused 100% mortality at 39 days. Fish fed with 100 ppb TCDD food had TCDD accumulation of 47.37 ppb (ng TCDD/g fish) in whole fish at 28 days. Histological analysis from TCDD-treated trout sampled from 28 and 42 days revealed that obvious lesions were found in skin, oropharynx, liver, gas bladder, intestine, pancreas, nose and kidney. In addition, TCDD caused anemia in peripheral blood, decreases in abdominal fat, increases of remodeling of fin rays, edema in pericardium and retrobulbar hemorrhage in the 100 ppb TCDD-treated rainbow trout compared to the control group at 28 days. Dose- and time-dependent global gene expression analyses were performed using the cGRASP 16,000 (16K) cDNA microarray. TCDD-responsive whole body transcripts identified in the microarray experiments have putative functions involved in various biological processes including growth, cell proliferation, metabolic process, and immune system processes. Nine microarray-identified genes were selected for QPCR validation. CYP1A3 and CYP1A1 were common up-regulated genes and HBB1 was a common down

  1. 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...

  2. Influence of waterfalls on patterns of association between trout and ...

    African Journals Online (AJOL)

    The aim of this study was to establish whether waterfalls in the uKhahlamba Drakensberg Park, South Africa, are seasonally important in conserving indigenous Natal cascade frog Hadromophryne natalensis tadpole populations from the threat of predation by alien rainbow trout Oncorhynchus mykiss and brown trout Salmo ...

  3. 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

  4. 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.

  5. 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.

  6. 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.

  7. [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.

  8. Evaluation of the net energy value of glucose (cerelose) and maize starch in diets for rainbow trout (Salmo gairdneri).

    Science.gov (United States)

    Hilton, J W; Atkinson, J L; Slinger, S J

    1987-11-01

    1. Quadruplicate groups of rainbow trout (Salmo gairdneri) (mean body-weight 24.9 g) were reared on six dietary treatments (practical-type diets) in a modified paired-feeding experiment for 12 weeks at 15 degrees to determine the net energy (NE) value of starch and glucose to rainbow trout. 2. Three test diets were prepared to contain (g/kg): 0 supplemented carbohydrate (diet 1), 250 maize starch (diet 2) and 250 glucose (diet 3) and were given ad lib. to the trout with the feeding rate of the glucose- and starch-fed groups being monitored after each feeding. The remaining three treatments involved controlled feeding of the trout with diet 1 at 75% of the feed intake of trout reared on diets 2 and 3, so as to provide the same levels of protein and lipids without carbohydrate, and with diet 2 at 100% of the feed intake of trout reared on diet 3. 3. The difference in the final carcass energy of the ad lib.-fed group and the respective controlled-fed group divided by the amount of dietary glucose or starch energy consumed by the trout is the NE value for that carbohydrate. 4. The determined NE value of glucose was 3.99 kJ/g and starch 2.17 kJ/g, which is 24.6 and 12.6% respectively of the gross energy values of these carbohydrates in rainbow trout. 5. The results indicate that digestible energy and calculated metabolizable energy values for carbohydrates in rainbow trout overestimate the utilizable energy content of the diet.(ABSTRACT TRUNCATED AT 250 WORDS)

  9. 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.

  10. Potential population and assemblage influences of non-native trout on native nongame fish in Nebraska headwater streams

    Science.gov (United States)

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

    2014-01-01

    Non-native trout are currently stocked to support recreational fisheries in headwater streams throughout Nebraska. The influence of non-native trout introductions on native fish populations and their role in structuring fish assemblages in these systems is unknown. The objectives of this study were to determine (i) if the size structure or relative abundance of native fish differs in the presence and absence of non-native trout, (ii) if native fish-assemblage structure differs in the presence and absence of non-native trout and (iii) if native fish-assemblage structure differs across a gradient in abundances of non-native trout. Longnose dace Rhinichthys cataractae were larger in the presence of brown trout Salmo trutta and smaller in the presence of rainbow trout Oncorhynchus mykiss compared to sites without trout. There was also a greater proportion of larger white suckers Catostomus commersonii in the presence of brown trout. Creek chub Semotilus atromaculatus and fathead minnow Pimephales promelas size structures were similar in the presence and absence of trout. Relative abundances of longnose dace, white sucker, creek chub and fathead minnow were similar in the presence and absence of trout, but there was greater distinction in native fish-assemblage structure between sites with trout compared to sites without trout as trout abundances increased. These results suggest increased risk to native fish assemblages in sites with high abundances of trout. However, more research is needed to determine the role of non-native trout in structuring native fish assemblages in streams, and the mechanisms through which introduced trout may influence native fish populations.

  11. 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.

  12. 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.

  13. 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.

  14. 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.

  15. Outbreak of viral haemorrhagic septicaemic (VHS) in seawater-farmed rainbow trout in Norway caused by VHS virus genotype III

    DEFF Research Database (Denmark)

    Dale, Ole Bendik; Ørpetveit, Irene; Lyngstad, Trude Marie

    2009-01-01

    with slightly elevated mortality was confirmed at a seawater site rearing rainbow trout (90 to 440 g). Within 3 to 4 mo, the disease was recognised in 3 neighbouring sea sites with on-growing rainbow trout. The clinical, gross pathological and histopathological findings were in accordance with VHS......, and the diagnosis was confirmed by the detection of VHSV in brain and internal tissues by immunohistochemistry, cell culture and reverse transcriptase PCR (RT-PCR). Sequence analysis of the G-gene revealed that the isolated virus clustered with VHSV Genotype III and that the Norwegian isolate represents a unique...

  16. Detection of virus level in tissues of rainbow trout, Oncoryhinchus mykiss in clinical stage of viral hemorrhagic septicemia

    DEFF Research Database (Denmark)

    Ghiasi, Farzad; Olesen, Niels Jørgen

    2014-01-01

    tanks containing 70 fish. Group one was considered as control and group two infected by bath challenge with 103 TCID50 ml-1 of a VHS virus strain serologically similar to reference strain F1 with high pathogenicity in rainbow trout. At days 12, 13 and 14 post infection the organs including kidney...... liver, gill, pyloric caeca and skin showed the lowest with brain and spleen lying in between. These results point out that the significant levels of VHS virus found in rainbow trout tissues are relevant for the biosecurity in VHS-free areas mainly when fish are displayed and retained as whole fish....

  17. 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 ...

  18. Radioisotope x-ray fluorescence and neutron activation analyses of the trace element concentrations of the rainbow trout

    International Nuclear Information System (INIS)

    Akyuz, T.; Bassari, A.; Bolcal, C.; Sener, E.; Yildiz, M.; Kucer, R.; Kaplan, Z.; Dogan, G.; Akyuz, S.

    1999-01-01

    The muscles and livers of the ten rainbow trouts (Oncorhynchus mykiss; N, 1752) obtained from Sapanca, Aquaculture Facility of Aquatic Products Faculty, The University of Istanbul (Turkey), have been analysed quantitatively for some minor elements using the radioisotope energy dispersive X-ray fluorescence (EDXRF) and neutron activation analysis (NAA) methods. It was found that samples contain Na, K, Ca, Sc, Cs, Fe, Co, Cu, Zn, Se, Br, Rb, Sr, Au, La and Ce in different amounts. Comparison of the results with those of reference river fish samples indicated that agricultural rainbow trout samples from Sapanca region have higher Fe level. (author)

  19. 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.

  20. 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...

  1. Radioisotope X-ray fluorescence and neutron activation analyses of the trace element concentrations of the rainbow trout

    Science.gov (United States)

    Akyuz, T.; Bassari, A.; Bolcal, C.; Sener, E.; Yildiz, M.; Kucer, R.; Kaplan, Z.; Dogan, G.; Akyuz, S.

    1999-01-01

    The muscles and livers of the ten rainbow trouts ( Oncorhynchus mykiss; N, 1752) obtained from Sapanca, Aquaculture Facility of Aquatic Products Faculty, The University of Istanbul (Turkey), have been analysed quantitatively for some minor elements using the radioisotope energy dispersive X-ray fluorescence (EDXRF) and neutron activation analysis (NAA) methods. It was found that samples contain Na, K, Ca, Sc, Cs, Fe, Co, Cu, Zn, Se, Br, Rb, Sr, Au, La and Ce in different amounts. Comparison of the results with those of reference river fish samples indicated that agricultural rainbow trout samples from Sapanca region have higher Fe level.

  2. Endocrine changes associated with spawning behavior and social stimuli in a wild population of rainbow trout (Salmo gairdneri). II. Females

    OpenAIRE

    Liley, N.R.; Fostier, Alexis; Breton, B.; Tan, E.S.P.

    1986-01-01

    Rainbow trout (Salmo gairdneri) were collected from a natural spawning population at Pennask Lake, B.C. Blood samples taken from female trout at different stages of spawning were assayed by radioimmunoassay for gonadotropin (GtH), estradiol-17 beta (E2), androgens, including testosterone (T), and 17α-hydroxy-20 β-dihydroprogesterone (17,20-P). Plasma levels of androgen and estradiol were highest in females sampled shortly before ovulation (ogreeno females) and declined in ovulated and sexuall...

  3. 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...

  4. 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.

  5. 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).

  6. Oral and Anal Vaccination Confers Full Protection against Enteric Redmouth Disease (ERM) in Rainbow Trout

    Science.gov (United States)

    Ohtani, Maki; Strøm, Helene Kragelund; Raida, Martin Kristian

    2014-01-01

    The effect of oral vaccines against bacterial fish diseases has been a topic for debate for decades. Recently both M-like cells and dendritic cells have been discovered in the intestine of rainbow trout. It is therefore likely that antigens reaching the intestine can be taken up and thereby induce immunity in orally vaccinated fish. The objective of this project was to investigate whether oral and anal vaccination of rainbow trout induces protection against an experimental waterborne infection with the pathogenic enterobacteria Yersinia ruckeri O1 biotype 1 the causative agent of enteric redmouth disease (ERM). Rainbow trout were orally vaccinated with AquaVac ERM Oral (MERCK Animal Health) or an experimental vaccine bacterin of Y. ruckeri O1. Both vaccines were tested with and without a booster vaccination four months post the primary vaccination. Furthermore, two groups of positive controls were included, one group receiving the experimental oral vaccine in a 50 times higher dose, and the other group receiving a single dose administered anally in order to bypass the stomach. Each group was bath challenged with 6.3×108 CFU/ml Y. ruckeri, six months post the primary vaccination. The challenge induced significant mortality in all the infected groups except for the groups vaccinated anally with a single dose or orally with the high dose of bacterin. Both of these groups had 100% survival. These results show that a low dose of Y. ruckeri bacterin induces full protection when the bacterin is administered anally. Oral vaccination also induces full protection, however, at a dose 50 times higher than if the fish were to be vaccinated anally. This indicates that much of the orally fed antigen is digested in the stomach before it reaches the second segment of the intestine where it can be taken up as immunogenic antigens and presented to lymphocytes. PMID:24705460

  7. Some factors affecting the resistance of rainbow trout (Salmo gairdnerii richardson) to acid waters

    Energy Technology Data Exchange (ETDEWEB)

    Lloyd, R; Jordan, D H.M.

    1964-01-01

    The pH value at which acid solutions proved lethal to rainbow trout within 1 day was unaffected by the pH value to which the fish had been acclimatized. In waters of total hardness 320, 40, and 12 ppM as CaCO/sub 3/, 50 percent of the fish died in 4 days at pH values of 4.18, 4.22, and 4.25 respectively. The relation between log survival time and pH value, up to pH 3.95 at which the median period of survival is 34 hr, is substantially linear and is unaffected by the presence of up to 50 ppM free carbon dioxide. Although at higher pH values this linear relation is maintained in the presence of 1.5 ppM (and possibly of up to 10 ppM) free carbon dioxide, at higher concentrations the survival time was progressively diminished by up to 50 ppM free carbon dioxide. Extrapolation of the results suggests that exposure to pH values below 5.0 for about 3 months might be harmful to rainbow trout when little free carbon dioxide was present in the water, but if an acid discharge were to rinse the free carbon dioxide content to 20 ppM, mortalities might occur within about 3 months when the ph value of the water fell below 6.0. Comparisons of the pH value and total carbon dioxide content of the blood of rainbow trout killed in acid solutions with those of control fish suggested that death was due to acidaemia.

  8. 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.

  9. Computational estimation of rainbow trout estrogen receptor binding affinities for environmental estrogens

    International Nuclear Information System (INIS)

    Shyu, Conrad; Cavileer, Timothy D.; Nagler, James J.; Ytreberg, F. Marty

    2011-01-01

    Environmental estrogens have been the subject of intense research due to their documented detrimental effects on the health of fish and wildlife and their potential to negatively impact humans. A complete understanding of how these compounds affect health is complicated because environmental estrogens are a structurally heterogeneous group of compounds. In this work, computational molecular dynamics simulations were utilized to predict the binding affinity of different compounds using rainbow trout (Oncorhynchus mykiss) estrogen receptors (ERs) as a model. Specifically, this study presents a comparison of the binding affinity of the natural ligand estradiol-17β to the four rainbow trout ER isoforms with that of three known environmental estrogens 17α-ethinylestradiol, bisphenol A, and raloxifene. Two additional compounds, atrazine and testosterone, that are known to be very weak or non-binders to ERs were tested. The binding affinity of these compounds to the human ERα subtype is also included for comparison. The results of this study suggest that, when compared to estradiol-17β, bisphenol A binds less strongly to all four receptors, 17α-ethinylestradiol binds more strongly, and raloxifene has a high affinity for the α subtype only. The results also show that atrazine and testosterone are weak or non-binders to the ERs. All of the results are in excellent qualitative agreement with the known in vivo estrogenicity of these compounds in the rainbow trout and other fishes. Computational estimation of binding affinities could be a valuable tool for predicting the impact of environmental estrogens in fish and other animals.

  10. Chronic exposure to dietary selenomethionine increases gonadal steroidogenesis in female rainbow trout

    Energy Technology Data Exchange (ETDEWEB)

    Wiseman, Steve, E-mail: steve.wiseman@usask.ca [Toxicology Centre, University of Saskatchewan, Saskatoon, SK, S7N 5B3 (Canada); Thomas, Jith K.; Higley, Eric; Hursky, Olesya [Toxicology Centre, University of Saskatchewan, Saskatoon, SK, S7N 5B3 (Canada); Pietrock, Michael [Toxicology Centre, University of Saskatchewan, Saskatoon, SK, S7N 5B3 (Canada); Department of Veterinary Biomedical Sciences, University of Saskatchewan, Saskatoon, SK, S7N 5B4 (Canada); Raine, Jason C. [Toxicology Centre, University of Saskatchewan, Saskatoon, SK, S7N 5B3 (Canada); Giesy, John P. [Toxicology Centre, University of Saskatchewan, Saskatoon, SK, S7N 5B3 (Canada); Department of Veterinary Biomedical Sciences, University of Saskatchewan, Saskatoon, SK, S7N 5B4 (Canada); Department of Zoology, College of Science, King Saud University, P.O. Box 2455, Riyadh 11451 (Saudi Arabia); Department of Biology and Chemistry, City University of Hong Kong, Kowloon, Hong Kong (Hong Kong); School of Biological Sciences, University of Hong Kong, Hong Kong (Hong Kong); Department of Zoology, Center for Integrative Toxicology, Michigan State University, East Lansing, MI 48824 (United States); State Key Laboratory of Pollution Control and Resource Reuse and School of the Environment, Nanjing University, Nanjing (China); Janz, David M. [Toxicology Centre, University of Saskatchewan, Saskatoon, SK, S7N 5B3 (Canada); Department of Veterinary Biomedical Sciences, University of Saskatchewan, Saskatoon, SK, S7N 5B4 (Canada); Hecker, Markus [Toxicology Centre, University of Saskatchewan, Saskatoon, SK, S7N 5B3 (Canada); School of Environment and Sustainability, University of Saskatchewan, Saskatoon, SK, S7N 5C8 (Canada)

    2011-10-15

    Selenomethionine (Se-Met) is the major dietary form of selenium (Se). Detrimental effects have been associated with exposure to elevated dietary selenium. Previous studies have demonstrated effects of Se on the endocrine system, in particular effects on cortisol and thyroid hormones. However, no information is available regarding effects of Se on sex steroid hormones. In the present study, effects of dietary exposure to an environmentally relevant concentration (4.54 mg/kg wet weight (ww)) of Se-Met for 126 days on concentrations of sex steroid hormones in blood plasma of female rainbow trout were determined. Furthermore, the molecular basis for effects of Se-Met on plasma sex steroid hormone concentrations was investigated. Concentrations of androstenedione (A), estrone (E1), and estradiol (E2) were 39.5-, 3.8-, and 12.7-fold greater in plasma of treated females than the untreated controls, respectively. Testosterone (T) was detected only in plasma of treated females. The greater E2 concentration stimulated greater transcript abundance of vitellogenin (vtg) and zona-radiata protein (zrp). Female rainbow trout exposed to Se-Met had greater transcript abundance of key steroidogenic proteins and enzymes, including peripheral benzodiazepine receptor (pbr), cytochrome P450 side-chain cleavage (P450scc), and 3{beta}-hydroxysteroid dehydrogenase (3{beta}-hsd). Exposure to Se-Met did not affect transcript abundance of luteinizing hormone (lh) or follicle stimulating hormone (fsh). Similarly, there was no change in transcript abundance of luteinizing hormone receptor (lhr) or follicle stimulating hormone receptor (fshr). Long-term exposure to dietary Se-Met has the potential to stimulate vitellogenesis in female rainbow trout by directly stimulating ovarian tissue steroidogenesis. This is the first study to report effects of Se on sex steroid hormone production in fish.

  11. 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...

  12. 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...

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

    Science.gov (United States)

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

    1966-01-01

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

  14. Viral haemorrhagic septicaemia (VHS) outbreaks in Finnish-rainbow trout farms

    DEFF Research Database (Denmark)

    Raja-Halli, M.; Vehmas, T.K.; Rimaila-Parnanen, E.

    2006-01-01

    and NV gene regions of Finnish VHSV isolates collected between 2000 and 2004 revealed that all isolates were closely related, with 99.3 to 100% nucleotide identity, which suggests the same origin of infection. Phylogenetic analysis revealed that they were closely related to the old freshwater isolates...... from rainbow trout in Denmark and to one old marine isolate from cod in the Baltic Sea, and that they were located close to the presumed ancestral source. As the Finnish isolates induce lower mortality than freshwater VHSV isolates in infection experiments, they could represent an intermediate stage...

  15. Fish culture in heated effluents (eastern Europe). [Growth increase in carp and rainbow trout

    Energy Technology Data Exchange (ETDEWEB)

    Backiel, T; Gay, B; La Croix, M J.B.; Ophel, I L [eds.

    1976-01-01

    Dependence of growth and reproduction of cultivated fishes on temperature are briefly reviewed. Experiments with and commercial-size operations of various methods of fish culture with the use of heated effluents are exemplified. Cage culture, earthen ponds, flowing water culture have demonstrated possibilities of growth increase in carp and rainbow trout and of controlled reproduction of the former. Problems involved in utilization of various systems and several points of view on the use of low-grade heat for fish culture are considered.

  16. 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.

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

    International Nuclear Information System (INIS)

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

    1987-01-01

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

  18. Lake Roosevelt Rainbow Trout : Habitat/Passage Improvement Project Annual Report 2000.

    Energy Technology Data Exchange (ETDEWEB)

    Sear, Sheri

    2001-02-01

    Lake Franklin D. Roosevelt was created with the completion of the Grand Coulee Dam in 1942. The lake stretches 151 miles up-stream to the International border between the United States and Canada at the 49th parallel. Increased recreational use, subsistence and sport fishing has resulted in intense interest and possible exploitation of the resources within the lake. Previous studies of the lake and its fishery have been limited. Early studies indicate that natural reproduction within the lake and tributaries are not sufficient to support a rainbow trout (Onchoryhnchus mykiss) fishery (Scholz et. al., 1988). These studies indicate that the rainbow trout population may be limited by lack of suitable habitat for spawning and rearing (Scholz et. al., 1988). The initial phase of this project (Phase I, baseline data collection- 1990-91) was directed at the assessment of limiting factors such as quality and quantity of available spawning gravel, identification of passage barriers, and assessment of other limiting factors. Population estimates were conducted using the Seber/LeCren removal/depletion method. After the initial assessment of stream parameters, several streams were selected for habitat/passage improvement projects (Phase II, implementation-1992-96). At the completion of project habitat improvements, the final phase (Phase III, monitoring) began. This phase will assess changes and gauge the success achieved through the improvements. The objective of the project is to correct passage barriers and improve habitat conditions of selected tributaries to Lake Roosevelt for adfluvial rainbow trout that utilize tributary streams for spawning and rearing. Streams with restorable habitats were selected for improvements. Completion of improvement efforts should increase the adfluvial rainbow trout contribution to the resident fishery in Lake Roosevelt. Three co-operating agencies, the Confederated Tribes of the Colville Reservation (CCT), the Spokane Tribe of Indians (STI

  19. Lake Roosevelt Rainbow Trout : Habitat/Passage Improvement Project Annual Report 1999.

    Energy Technology Data Exchange (ETDEWEB)

    Jones, Charles D.

    2000-02-01

    Lake Franklin D. Roosevelt was created with the completion of the Grand Coulee Dam in 1942. The lake stretches 151 miles up-stream to the International border between the United States and Canada at the 49th parallel. Increased recreational use, subsistence and sport fishing has resulted in intense interest and possible exploitation of the resources within the lake. Previous studies of the lake and its fishery have been limited. Early studies indicate that natural reproduction within the lake and tributaries are not sufficient to support a rainbow trout (Onchoryhnchus mykiss) fishery (Scholz et. al., 1988). These studies indicate that the rainbow trout population may be limited by lack of suitable habitat for spawning and rearing (Scholz et. al., 1988). The initial phase of this project (Phase I, baseline data collection- 1990-91) was directed at the assessment of limiting factors such as quality and quantity of available spawning gravel, identification of passage barriers, and assessment of other limiting factors. Population estimates were conducted using the Seber/LeCren removal/depletion method. After the initial assessment of stream parameters, several streams were selected for habitat/passage improvement projects (Phase II, implementation-1992-96). At the completion of project habitat improvements, the final phase (Phase III, monitoring) began. This phase will assess changes and gauge the success achieved through the improvements. The objective of the project is to correct passage barriers and improve habitat conditions of selected tributaries to Lake Roosevelt for adfluvial rainbow trout that utilize tributary streams for spawning and rearing. Streams with restorable habitats were selected for improvements. Completion of improvement efforts should increase the adfluvial rainbow trout contribution to the resident fishery in Lake Roosevelt. Three co-operating agencies, the Confederated Tribes of the Colville Reservation (CCT), the Spokane Tribe of Indians (STI

  20. A New Single Nucleotide Polymorphism Database for Rainbow Trout Generated Through Whole Genome Resequencing

    Directory of Open Access Journals (Sweden)

    Guangtu Gao

    2018-04-01

    Full Text Available Single-nucleotide polymorphisms (SNPs are highly abundant markers, which are broadly distributed in animal genomes. For rainbow trout (Oncorhynchus mykiss, SNP discovery has been previously done through sequencing of restriction-site associated DNA (RAD libraries, reduced representation libraries (RRL and RNA sequencing. Recently we have performed high coverage whole genome resequencing with 61 unrelated samples, representing a wide range of rainbow trout and steelhead populations, with 49 new samples added to 12 aquaculture samples from AquaGen (Norway that we previously used for SNP discovery. Of the 49 new samples, 11 were double-haploid lines from Washington State University (WSU and 38 represented wild and hatchery populations from a wide range of geographic distribution and with divergent migratory phenotypes. We then mapped the sequences to the new rainbow trout reference genome assembly (GCA_002163495.1 which is based on the Swanson YY doubled haploid line. Variant calling was conducted with FreeBayes and SAMtools mpileup, followed by filtering of SNPs based on quality score, sequence complexity, read depth on the locus, and number of genotyped samples. Results from the two variant calling programs were compared and genotypes of the double haploid samples were used for detecting and filtering putative paralogous sequence variants (PSVs and multi-sequence variants (MSVs. Overall, 30,302,087 SNPs were identified on the rainbow trout genome 29 chromosomes and 1,139,018 on unplaced scaffolds, with 4,042,723 SNPs having high minor allele frequency (MAF > 0.25. The average SNP density on the chromosomes was one SNP per 64 bp, or 15.6 SNPs per 1 kb. Results from the phylogenetic analysis that we conducted indicate that the SNP markers contain enough population-specific polymorphisms for recovering population relationships despite the small sample size used. Intra-Population polymorphism assessment revealed high level of polymorphism and

  1. Variation in angler distribution and catch rates of stocked rainbow trout in a small reservoir

    Science.gov (United States)

    Harmon, Brian S.; Martin, Dustin R.; Chizinski, Christopher J.; Pope, Kevin L.

    2018-01-01

    We investigated the spatial and temporal relationship of catch rates and angler party location for two days following a publicly announced put-and-take stocking of rainbow trout (Oncorhynchus mykiss). Catch rates declined with time since stocking and distance from stocking. We hypothesized that opportunity for high catch rates would cause anglers to fish near the stocking location and disperse with time, however distance between angler parties and stocking was highly variable at any given time. Spatially explicit differences in catch rates can affect fishing quality. Further research could investigate the variation between angler distribution and fish distribution within a waterbody.

  2. Effect of lowered oxygen in aquaculture on rainbow trout muscle quality investigated by a proteomic approach

    DEFF Research Database (Denmark)

    Wulff, Tune

    , this can help pinpointing which changes in the fish muscle are due to hypoxia and which are down to other stressors. This can aid the aquaculture industry when evaluating the type of stressors mostly affecting food quality, allowing an optimisation of rainbow trout handling accordingly....... it significantly reduces the quality of the major edible part of the fish. Fish in aquaculture are stressed by handling (e.g. sorting, crowding and transportation) prior to slaughter and it is well established that such stress leads to reduced textural quality of the fish. However, it is still unclear which...

  3. 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...

  4. Association between increased antibody level and protection in Yersinia ruckeri bacterin immersion vaccinated rainbow trout

    DEFF Research Database (Denmark)

    Raida, Martin Kristian; Nylén, Jørgen; Holten-Andersen, Lars

    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 (AquaVacTM ERM vet) or an experimental Y. ruckeri bacterin. Half of the trout...... vaccinated with AquaVacTM ERM vet received an oral booster (AquaVacTM ERM Oral vet). Sub-groups of the fish from each group were subsequently exposed to 1x109 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) (Plevels were measured with ELISA...

  5. Exogenous lactate supply affects lactate kinetics of rainbow trout, not swimming performance

    Science.gov (United States)

    Omlin, Teye; Langevin, Karolanne

    2014-01-01

    Intense swimming causes circulatory lactate accumulation in rainbow trout because lactate disposal (Rd) is not stimulated as strongly as lactate appearance (Ra). This mismatch suggests that maximal Rd is limited by tissue capacity to metabolize lactate. This study uses exogenous lactate to investigate what constrains maximal Rd and minimal Ra. Our goals were to determine how exogenous lactate affects: 1) Ra and Rd of lactate under baseline conditions or during graded swimming, and 2) exercise performance (critical swimming speed, Ucrit) and energetics (cost of transport, COT). Results show that exogenous lactate allows swimming trout to boost maximal Rd lactate by 40% and reach impressive rates of 56 μmol·kg−1·min−1. This shows that the metabolic capacity of tissues for lactate disposal is not responsible for setting the highest Rd normally observed after intense swimming. Baseline endogenous Ra (resting in normoxic water) is not significantly reduced by exogenous lactate supply. Therefore, trout have an obligatory need to produce lactate, either as a fuel for oxidative tissues and/or from organs relying on glycolysis. Exogenous lactate does not affect Ucrit or COT, probably because it acts as a substitute for glucose and lipids rather than extra fuel. We conclude that the observed 40% increase in Rd lactate is made possible by accelerating lactate entry into oxidative tissues via monocarboxylate transporters (MCTs). This observation together with the weak expression of MCTs and the phenomenon of white muscle lactate retention show that lactate metabolism of rainbow trout is significantly constrained by transmembrane transport. PMID:25121611

  6. 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.

  7. Genetic investigation of natural hybridization between rainbow and coastal cutthroat trout in the copper River Delta, Alaska

    Science.gov (United States)

    Williams, I.; Reeves, G.H.; Graziano, S.L.; Nielsen, J.L.

    2007-01-01

    Molecular genetic methods were used to quantify natural hybridization between rainbow trout Oncorhynchus mykiss or steelhead (anadromous rainbow trout) and coastal cutthroat trout O. clarkii clarkii collected in the Copper River delta, Southeast Alaska. Eleven locations were sampled to determine the extent of hybridization and the distribution of hybrids. Four diagnostic nuclear microsatellite loci and four species-specific simple sequence repeat markers were used in combination with restriction fragment length polymorphism analyses of NADH dehydrogenase 5/6 (ND5/6) mitochondrial DNA (mtDNA) to investigate the genetic structure of trout from both species and identify putative interspecific hybrids. Hybrids were found in 7 of the 11 streams sampled in the Copper River delta, the extent of hybridization across all streams varying from 0% to 58%. Hybrid trout distribution appeared to be nonrandom, most individuals of mixed taxonomic ancestry being detected in streams containing rainbow trout rather than in streams containing coastal cutthroat trout. Genotypic disequilibrium was observed among microsatellite loci in populations with high levels of hybridization. We found no significant correlation between unique stream channel process groups and the number of hybrid fish sampled. Eighty-eight percent of fish identified as first-generation hybrids (F1) in two populations contained coastal cutthroat trout mtDNA, suggesting directionality in hybridization. However, dominance of coastal cutthroat trout mtDNA was not observed at a third location containing F1 hybrids, indicating that interspecific mating behavior varied among locations. Backcrossed individuals were found in drainages lacking F1 hybrids and in populations previously thought to contain a single species. The extent and distribution of backcrossed individuals suggested that at least some hybrids are reproductively viable and backcrossed hybrid offspring move throughout the system.

  8. 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%.

  9. Voluntary feed intake in rainbow trout is regulated by diet-induced differences in oxygen use.

    Science.gov (United States)

    Saravanan, Subramanian; Geurden, Inge; Figueiredo-Silva, A Cláudia; Kaushik, Sadasivam; Verreth, Johan; Schrama, Johan W

    2013-06-01

    This study investigated the hypothesis that the voluntary feed intake in fish is regulated by diet-induced differences in oxygen use. Four diets were prepared with a similar digestible protein:digestible energy ratio (18 mg/kJ), but which differed in the composition of nonprotein energy source. This replacement of fat (F) by starch (S) was intended to create a diet-induced difference in oxygen use (per unit of feed): diets F30-S70, F50-S50, F65-S35, and F80-S20 with digestible fat providing 28, 49, 65, and 81% of the nonprotein digestible energy (NPDE), respectively. Each diet was fed to satiation to triplicate groups of 20 rainbow trout for 6 wk. As expected, diet-induced oxygen use decreased linearly (R(2) = 0.89; P digestible and metabolizable energy intakes of trout slightly increased with increasing NPDE as fat (i.e., decreasing starch content) (R(2) = 0.30, P = 0.08; and R(2) = 0.34, P = 0.05, respectively). Oxygen consumption of trout fed to satiation declined with increasing dietary NPDE as fat (R(2) = 0.48; P = 0.01). The inverse relation between digestible energy intake of trout and the diet-induced oxygen use (R(2) = 0.33; P = 0.05) suggests a possible role of diet-induced oxygen use in feed intake regulation as shown by the replacement of dietary fat by starch.

  10. 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...

  11. Kootenai River fisheries investigations. Chapter 3: Mainstem habitat use and recruitment estimates of rainbow trout in the Kootenai River, Idaho. Annual report 1996

    International Nuclear Information System (INIS)

    Fredericks, J.; Hendricks, S.

    1997-09-01

    The objective of this study was to determine if recruitment is limiting the population of rainbow trout Oncorhynchus mykiss in the mainstem Kootenai River. The authors used snorkeling and electrofishing techniques to estimate juvenile rainbow trout density and total numbers in Idaho tributaries, and they trapped juvenile outmigrants to identify the age at which juvenile trout migrate from tributaries to the Kootenai River. The authors radio and reward-tagged post-spawn adult rainbow trout captured in Deep Creek to identify river reach and habitat used by those fish spawning and rearing in the Deep Creek drainage. They also conducted redd surveys in the Kootenai River to determine the extent of mainstem spawning. Based on the amount of available habitat and juvenile rainbow trout densities, the Deep Creek drainage was the most important area for juvenile production. Population estimates of age 0, age 1+, and age 2+ rainbow trout indicated moderate to high densities in several streams in the Deep Creek drainage whereas other streams, such as Deep Creek, had very low densities of juvenile trout. The total number of age 0, age 1+, and age 2+ rainbow trout in Deep Creek drainage in 1996 was estimated to be 63,743, 12,095, and 3,095, respectively. Radio telemetry efforts were hindered by the limited range of the transmitters, but movements of a radio-tagged trout and a returned reward tag indicated that at least a portion of the trout utilizing the Deep Creek drainage migrated downriver from the mouth of Deep Creek to the meandering section of river. They found no evidence of mainstem spawning by rainbow trout, but redd counting efforts were hindered by high flows from mid-April through June

  12. 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.

  13. Rainbow trout (Salmo irideus produced in Finland I. Bacterial spoilage and amino acid composition of fresh rainbow trout during refrigerated storage

    Directory of Open Access Journals (Sweden)

    Fritz P. Niinivaara

    1966-12-01

    Full Text Available Bacteriological spoilage, organoleptical quality and amino acid composition of fresh trout were studied during storage at +4– +6° C. Experiments were carried out with living fish (control, with fish 4 hours after killing and during storage. The fish were kept in air, in ice and packed in polyethylene and vacuum bags. It was observed that the type of packing considerably influences both the bacteriological and organoleptical quality. These changes were not, however, directly correlated with each other. In connection with vacuum packing, the amounts of anaerobic sulphide producing bacteria were so high that this aspect needs a detailed investigation before vacuum packing can be recommended for fresh trout. The amino acid composition of iced trout changed only slightly during storage. Current experiments concerning changes in volatile amino acid contents will provide additional information in this respect.

  14. Immunity to viral haemorrhagic septicaemia (VHS) following DNA vaccination of rainbow trout at an early life-stage

    DEFF Research Database (Denmark)

    Lorenzen, Niels; Lorenzen, Ellen; Einer-Jensen, Katja

    2001-01-01

    -vaccination respectively, revealed that a highly protective and lasting immunity was established shortly after vaccination, in accordance with earlier experiments with larger fish. The defence mechanisms activated by the DNA vaccine are thus functional at an early life-stage in rainbow trout....

  15. Nitrification in moving bed and fixed bed biofilters treating effluent water from a large commercial outdoor rainbow trout RAS

    DEFF Research Database (Denmark)

    Suhr, Karin; Pedersen, Per Bovbjerg

    2010-01-01

    The nitrification performance of two fixed bed (FB) biofilters and two moving bed (MB) biofilters was evaluated. They received the same cold (8 degrees C) influent water from a commercial outdoor RAS facility producing rainbow trout (average density 32 kg m(-3)). The filters were constructed as f...

  16. 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 ...

  17. 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.

  18. Molecular crosstalk between a chemical and a biological stressor and consequences on disease manifestation in rainbow trout

    Science.gov (United States)

    The aim of the present study was to examine the molecular and organism reaction of rainbow trout, Oncorhynchus mykiss, to the combined impact of two environmental stressors. The two stressors were the myxozoan parasite, Tetracapsuloides bryosalmonae, which is the etiological agent of proliferative k...

  19. 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.

  20. Effects of diet composition and ultrasound treatment on particle size distribution and carbon bioavailability in feces of rainbow trout

    NARCIS (Netherlands)

    Meriac, A.; Tilburg, van T.; Eding, E.H.; Kamstra, A.; Schrama, J.W.; Verreth, J.A.J.

    2015-01-01

    The effect of a high and low non-starch polysaccharide diet (HNSP and LNSP diet) and ultrasound treatment on particle size distribution and carbon bioavailability in fecal waste of rainbow trout (Oncorynchus mykiss) was studied. Feces were collected from four flow-through fish tanks, two tanks fed

  1. 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...

  2. 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...

  3. 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...

  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. Validation of abundance estimates from mark-recapture and removal techniques for rainbow trout captured by electrofishing in small streams

    Science.gov (United States)

    Amanda E. Rosenberger; Jason B. Dunham

    2005-01-01

    Estimation of fish abundance in streams using the removal model or the Lincoln–Peterson mark–recapture model is a common practice in fisheries. These models produce misleading results if their assumptions are violated. We evaluated the assumptions of these two models via electrofishing of rainbow trout Oncorhynchus mykiss in central Idaho streams....

  6. 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...

  7. 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...

  8. Comparative evaluation of infection methods and environmental factors on challenge success: Aeromonas salmonicida infection in vaccinated rainbow trout

    DEFF Research Database (Denmark)

    Chettri, Jiwan Kumar; Skov, Jakob; Jaafar, Rzgar M.

    2015-01-01

    When testing vaccine-induced protection an effective and reliable challenge method is a basic requirement and we here present a comparative study on different challenge methods used for infection of rainbow trout Oncorhynchus mykiss with Aeromonas salmonicida, a bacterial pathogen eliciting...

  9. Danish sea reared rainbow trout suffer from furunculosis despite vaccination - How can applied research help to solve the problem?

    DEFF Research Database (Denmark)

    Skall, H. F.; Lorenzen, E.; Kjær, T. E.

    2015-01-01

    Despite vaccination by intraperitoneal injection with oil-adjuvanted vaccines against vibriosis and furunculosis, sea reared rainbow trout in Denmark often develop furunculosis and occasionally vibriosis during warm summer periods. This implies an excessive use of antibiotics and has also decreas...

  10. Rainbow trout adaptation to a warmer Patagonia and its potential to increase temperature tolerance in cultured stocks

    Directory of Open Access Journals (Sweden)

    Sonia Alejandra Crichigno

    2018-02-01

    Full Text Available The viability of rainbow trout Oncorhynchus mykiss (Walbaum, 1792 culture is being challenged progressively by global warming. Previous trials with Australian and Japanese rainbow trout lines suggested that improvements in thermal performance may be possible. Here, we hypothesized that strain-related differences in physiological response to temperature exist between a north Patagonian hatchery stock (CENSALBA, a Neotropical one (Criadero Boca de Río, and a thermal stream (Valcheta population of wild introduced rainbow trout. This was tested by comparing, at 20 °C, the thermal preference, specific metabolic rate, thermal tolerance, growth, and condition on juveniles of the three strains, and on a Valcheta stream male x CENSALBA female F1 cross. Preferred temperature (PT and loss of equilibrium temperature (LET, a measure of thermal tolerance of Valcheta stream and F1 were significantly higher than those of CENSALBA, and the average PTs of Valcheta stream and F1 were higher than the 95% confidence interval of available reference data for rainbow trout. These results suggest that the F1, reared under standard hatchery conditions and selected by growth and thermal preference, presents higher thermal preference and higher thermal tolerance than the current CENSALBA hatchery stock. Introduction of this naturally adapted strain to hatchery stocks would likely result in the improvement of their temperature resistance to warmer waters. Current studies on adults of this F1 generation are underway.

  11. Sequence analysis of the internal transcribed spacer (ITS) region reveals a novel clade of Ichthyophonus sp. from rainbow trout.

    Science.gov (United States)

    Rasmussen, C; Purcell, M K; Gregg, J L; LaPatra, S E; Winton, J R; Hershberger, P K

    2010-03-09

    The mesomycetozoean parasite Ichthyophonus hoferi is most commonly associated with marine fish hosts but also occurs in some components of the freshwater rainbow trout Oncorhynchus mykiss aquaculture industry in Idaho, USA. It is not certain how the parasite was introduced into rainbow trout culture, but it might have been associated with the historical practice of feeding raw, ground common carp Cyprinus carpio that were caught by commercial fisherman. Here, we report a major genetic division between west coast freshwater and marine isolates of Ichthyophonus hoferi. Sequence differences were not detected in 2 regions of the highly conserved small subunit (18S) rDNA gene; however, nucleotide variation was seen in internal transcribed spacer loci (ITS1 and ITS2), both within and among the isolates. Intra-isolate variation ranged from 2.4 to 7.6 nucleotides over a region consisting of approximately 740 bp. Majority consensus sequences from marine/anadromous hosts differed in only 0 to 3 nucleotides (99.6 to 100% nucleotide identity), while those derived from freshwater rainbow trout had no nucleotide substitutions relative to each other. However, the consensus sequences between isolates from freshwater rainbow trout and those from marine/anadromous hosts differed in 13 to 16 nucleotides (97.8 to 98.2% nucleotide identity).

  12. 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 (...

  13. 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].

  14. 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...

  15. 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.

  16. 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

  17. 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...

  18. Comparative evaluation of administration methods for a vaccine protecting rainbow trout against Yersinia ruckeri O1 biotype 2 infections

    DEFF Research Database (Denmark)

    Chettri, Jiwan Kumar; Deshmukh, Sidhartha; Holten-Andersen, Lars

    2013-01-01

    (using a commercial vaccine AquaVac® RELERA™) does not provide full protection. We elucidated by a controlled duplicated experiment if different vaccine administration methods can improve level and extent of protection. Rainbow trout, Oncorhynchus mykiss were vaccinated by: (1) a single immersion...

  19. 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...

  20. Physiological and biochemical responses of rainbow trout and brook trout exposed to elevated selenium from coal mines

    Energy Technology Data Exchange (ETDEWEB)

    Miller, L.; Rasmussen, J.; Hontela, A. [Lethbridge Univ., Lethbridge, AB (Canada); Palace, V.; Carroll, L. [Fisheries and Oceans Canada, Winnipeg, MB (Canada); Wang, F. [Manitoba Univ., Winnipeg, MB (Canada)

    2009-07-01

    Since selenium (Se) is an element that bioaccumulates, anthropogenic activities in areas that already have high Se in parent rock can result in an increase in Se in aquatic systems. Se causes reproductive deformities in rainbow trout (RT), at lower concentrations than for brook trout (BT). This presentation reported on a study conducted at coal mines in northeastern Alberta in which juvenile hatchery-reared RT and BT were stocked into 2 reference and 2 Se contaminated end pit lakes. Fish were sampled at 0, 6, and 12 months after stocking, and will be sampled at 18 and 24 months. Water Se levels were found to be high in contaminated lakes. Selenite, the more toxic form of Se, was the highest in Pit C4. Liver glutathione levels were similar in the 2 fish species, and cellular damage in the fish was beginning to increase. At 6 months, liver glycogen levels were higher in the BT than in the RT, but no tangible site specific patterns emerged. At all sites except Pit C4, the RT were in better condition than BT. BT from Pit C4 also had a lower ability to secrete cortisol, suggesting that the elevated selenite levels may negatively affect fish. Se accumulation results from 28 fish sampled at 12 months were also discussed.

  1. 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.

  2. Can VHS Virus Bypass the Protective Immunity Induced by DNA Vaccination in Rainbow Trout?

    Directory of Open Access Journals (Sweden)

    Dagoberto Sepúlveda

    Full Text Available DNA vaccines encoding viral glycoproteins have been very successful for induction of protective immunity against diseases caused by rhabdoviruses in cultured fish species. However, the vaccine concept is based on a single viral gene and since RNA viruses are known to possess high variability and adaptation capacity, this work aimed at evaluating whether viral haemorrhagic septicaemia virus (VHSV, an RNA virus and member of Rhabdoviridae family, was able to evade the protective immune response induced by the DNA vaccination of rainbow trout. The experiments comprised repeated passages of a highly pathogenic VHSV isolate in a fish cell line in the presence of neutralizing fish serum (in vitro approach, and in rainbow trout immunized with the VHS DNA vaccine (in vivo approach. For the in vitro approach, the virus collected from the last passage (passaged virus was as sensitive as the parental virus to serum neutralization, suggesting that the passaging did not promote the selection of virus populations able to bypass the neutralization by serum antibodies. Also, in the in vivo approach, where virus was passaged several times in vaccinated fish, no increased virulence nor increased persistence in vaccinated fish was observed in comparison with the parental virus. However, some of the vaccinated fish did get infected and could transmit the infection to naïve cohabitant fish. The results demonstrated that the DNA vaccine induced a robust protection, but also that the immunity was non-sterile. It is consequently important not to consider vaccinated fish as virus free in veterinary terms.

  3. Assessing the impact of waterborne and dietborne cadmium toxicity on susceptibility risk for rainbow trout

    International Nuclear Information System (INIS)

    Liao, Chung-Min; Ju, Yun-Ru; Chen, Wei-Yu; Chen, Bo-Ching

    2011-01-01

    The purpose of this study was to use a risk-based integrated-scale toxicological model to examine the impact of waterborne and dietborne cadmium (Cd) toxicity on rainbow trout (Oncorhynchus mykiss) susceptibility appraised with recent published data. A probabilistic assessment model was performed to estimate Cd susceptibility risk. The dose-response models were constructed based on two endpoints of % Cd in metabolically active pool (MAP) and susceptibility time that causes 50% effect (ST50). We further constructed an elimination-detoxification-recovery scheme to enhance the model predictive ability. We found a 95% probability of % Cd in gill and liver MAP exceeding 47-49% and it was likely (70% probability) to have exceeded 52-55%, but it was unlikely (30% probability) to have exceeded 56-60%. In contrast to gill and liver, gut had a relative lower Cd susceptibility risk (15-17% Cd in MAP) with a longer ST50. We suggested that the proposed probabilistic risk assessment framework can incorporate the elimination-detoxification-recovery scheme to help government based biomonitoring and bioassessment programs to prevent potential aquatic ecosystems and human health consequences. - Research Highlights: → An integrated-scale toxicological model was used to examine the impact of Cd on rainbow trout. → A probabilistic assessment model was performed to estimate Cd susceptibility risk. → An elimination-detoxification-recovery scheme was constructed to enhance the model predictive ability. → Gut had a relative lower Cd susceptibility risk than that in gill and liver.

  4. 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.

  5. 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.

  6. 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.

  7. Time-dependent changes in protein expression in rainbow trout muscle following hypoxia.

    Science.gov (United States)

    Wulff, Tune; Jokumsen, Alfred; Højrup, Peter; Jessen, Flemming

    2012-04-18

    Adaptation to hypoxia is a complex process, and individual proteins will be up- or down-regulated in order to address the main challenges at any given time. To investigate the dynamics of the adaptation, rainbow trout (Oncorhynchus mykiss) was exposed to 30% of normal oxygen tension for 1, 2, 5 and 24 h respectively, after which muscle samples were taken. The successful investigation of numerous proteins in a single study was achieved by selectively separating the sarcoplasmic proteins using 2-DE. In total 46 protein spots were identified as changing in abundance in response to hypoxia using one-way ANOVA and multivariate data analysis. Proteins of interest were subsequently identified by MS/MS following tryptic digestion. The observed regulation following hypoxia in skeletal muscle was determined to be time specific, as only a limited number of proteins were regulated in response to more than one time point. The cellular response to hypoxia included regulation of proteins involved in maintaining iron homeostasis, energy levels and muscle structure. In conclusion, this proteome-based study presents a comprehensive investigation of the expression profiles of numerous proteins at four different time points. This increases our understanding of timed changes in protein expression in rainbow trout muscle following hypoxia. Copyright © 2012 Elsevier B.V. All rights reserved.

  8. Effect of a traditional marinating on properties of rainbow trout fillet during chilled storage.

    Science.gov (United States)

    Maktabi, Siavash; Zarei, Mehdi; Chadorbaf, Milad

    2016-01-01

    In recent years, there has been an increasing interest in using food additives from natural sources to improve taste and also extend the shelf-life of semi-preserved foodstuffs. The aim of this study was to examine the chemical and microbiological changes promoted by a local marinating process in rainbow trout fillets during chilled storage. Fish fillets were immersed in marinades and stored at 4 ˚C for 10 days and were analyzed for total volatile basic nitrogen (TVN), thiobarbitoric acid (TBA), water holding capacity (WHC), pH, mesophilic and psychrophilic bacterial count every two days. Variations in TBA and WHC were not statistically significant between marinated and control groups. The values of TVN, pH, total psychrophilic bacteria count (TPC) and total mesophilic bacteria count (TMC) in marinated samples were significantly lower than controls. The most obvious finding of this study was that traditional marinated rainbow trout fillet stored in 4 ˚C had no undesirable changes at least for eight days.

  9. Growth type of vertebral centra and the hard tissue observed by microradiography of the rainbow trout

    International Nuclear Information System (INIS)

    Kubo, Y.; Asano, H.

    1987-01-01

    To clarify the growth feature and the structure of hard tissue, we studied the vertebral centrum of rainbow trout Salmo gairdneri, using three specimens (BL: 21.0, 29.0 and 40.0cm). We examined the ratio of centrum length to centrum diameter in each vertebral centrum and obtained the value of 0.8-1.0 in most centra. This indicates that the vertebral centra of rainbow trout belong to the so-called equivalent type. The hard tissue was observed by microradiography, with the longitudinal and cross sections (about 100 μm)cut through the center of notochordal pore. The microradiograph of thin section of centrurn differentiated serially and changed in pattern, but it is clear to sustain the specific characteristics. In longitudinal sections, the V-shaped part of bone was composed of structure like compact bone through the length of vertebral column. In cross sections, the notochordal pore was enclosed by the radial trabecular bones, the arrangement gradually turning toward the posterior centra like paired fans set opposite each other laterally

  10. Induction of monooxygenation in rainbow trout by polybrominated biphenyls: a comparative study.

    Science.gov (United States)

    Elcombe, C R; Lech, J J

    1978-01-01

    Two commercial polychlorinated biphenyl mixtures (Aroclor 1254 and Aroclor 1242) and one polybrominated biphenyl mixture (FireMaster BP-6) were examined for their abilities to induce hepatic microsomal monooxygenation in rainbow trout (Salmo gairdneri). Pretreatment of rainbow trout with Aroclors 1254 and 1242 (150 mg/kg IP) resulted in an approximate 10-fold induction of arylhydrocarbon (benzo[a]pyrene) hydroxylation, ethoxycoumarin-O-deethylation and ethoxyresorufin-O-deethylation within 7 days after injection. These enzyme activities remained elevated above control values for at least 2-3 weeks. Administration of FireMaster BP-6 (150 mg/kg IP) also resulted in an induction of several monooxygenase activities. Arylhydrocarbon (benzo[a]pyrene) hydroxylation, ethoxycoumarin-O-deethylation and ethoxyresorufin-O-deethylation were increased by 6-, 3,- and 25-fold, respectively. Only the latter two activities remained elevated two weeks post-injection. Ethylmorphine-N-demethylation was unaffected by the polyhalogenated biphenyls. Significant increases in P-450 hemoprotein were not observed after pretreatment with any of the polyhalogenated biphenyls studied. PMID:209992

  11. Sex-linkage of two enzyme loci in Oncorhyncus mykiss (rainbow trout)

    Science.gov (United States)

    Allendorf, F W; Gellman, W A; Thorgaard, G H

    1994-05-01

    We report the first sex-linked loci in Oncorhynchus mykiss (rainbow trout). Previous cytological and breeding experiments have demonstrated an XX/XY sex determining system in this and other salmonid species. Joint segregation data from fathers indicated an average of 8.1 per cent recombination between HEX-2 and the sex determining locus (SEX). The average recombination between HEX-2 and sSOD-1 in fathers was 26.8 per cent. No evidence of non-random segregation of HEX-2 and sSOD-1 was found in mothers; this difference in recombination rates between males and females is concordant with previous studies with rainbow trout and other salmonid species. These results also suggest the possibility that proper chromosomal pairing and segregation in salmonid males does not require a crossover event. Unlike the extreme XX/XY heteromorphy in mammals, functional alleles for HEX-2 and sSOD-1 occur on both the X and Y chromosomes. Significant non-random associations (i.e. gametic disequilibrium) occur between genotypes at HEX-2 and SEX in the hatchery population used for the inheritance study. This gametic disequilibrium has resulted in large changes in allele frequency at HEX-2 from one generation to the next and an excess of heterozygotes in comparison to expected binomial (i.e. Hardy-Weinberg) proportions.

  12. Metamorphosis of Ichthyophonus Schizonts Transiting the Gastrointestinal Tract of Experimentally Exposed Rainbow Trout.

    Science.gov (United States)

    Kocan, R M; LaPatra, S E

    2017-12-08

    Other than the initial infectious cell, schizonts are the only stage of the parasite Ichthyophonus sp. that has been identified in the tissues of a living host, and they are known to initiate new infections when ingested by a suitable host. However, after feeding Ichthyophonus-infected tissue to Rainbow Trout Oncorhynchus mykiss, we observed that once infection was initiated, some schizonts proceeded to develop into several other morphologic forms indistinguishable from those previously described from recently deceased hosts, decomposing infected corpses, and in vitro culture. It appeared that not all schizonts participated in the infection process; some initiated infection, as expected, while others passed into the intestines, where they morphed into multiple cell types (e.g., schizonts, some with partially digested or ruptured capsules, ameboid plasmodia, merozoites, hyphenated cells, and empty capsules). Some of these cells were viable when cultured, but none was infectious to naïve Rainbow Trout when administered by gavage. We posit that (1) not all tissue schizonts are programmed to perform the same function or (2) not all respond similarly to their environment. After consumption by a piscivore, those schizonts that do not initiate an infection do not die but rather metamorphose into different cell types as they transit the gastrointestinal tract and are ultimately released back into the aquatic environment through defecation. The fate of these cells after exiting the host is presently unknown, but they likely represent a segment of the Ichthyophonus life cycle. © 2017 American Fisheries Society.

  13. Assessing the impact of waterborne and dietborne cadmium toxicity on susceptibility risk for rainbow trout

    Energy Technology Data Exchange (ETDEWEB)

    Liao, Chung-Min, E-mail: cmliao@ntu.edu.tw [Department of Bioenvironmental Systems Engineering, National Taiwan University, Taipei, 10617, Taiwan (China); Ju, Yun-Ru; Chen, Wei-Yu [Department of Bioenvironmental Systems Engineering, National Taiwan University, Taipei, 10617, Taiwan (China); Chen, Bo-Ching [Department of Post-Modern Agriculture, Mingdao University, Changhua, 52345, Taiwan (China)

    2011-01-01

    The purpose of this study was to use a risk-based integrated-scale toxicological model to examine the impact of waterborne and dietborne cadmium (Cd) toxicity on rainbow trout (Oncorhynchus mykiss) susceptibility appraised with recent published data. A probabilistic assessment model was performed to estimate Cd susceptibility risk. The dose-response models were constructed based on two endpoints of % Cd in metabolically active pool (MAP) and susceptibility time that causes 50% effect (ST50). We further constructed an elimination-detoxification-recovery scheme to enhance the model predictive ability. We found a 95% probability of % Cd in gill and liver MAP exceeding 47-49% and it was likely (70% probability) to have exceeded 52-55%, but it was unlikely (30% probability) to have exceeded 56-60%. In contrast to gill and liver, gut had a relative lower Cd susceptibility risk (15-17% Cd in MAP) with a longer ST50. We suggested that the proposed probabilistic risk assessment framework can incorporate the elimination-detoxification-recovery scheme to help government based biomonitoring and bioassessment programs to prevent potential aquatic ecosystems and human health consequences. - Research Highlights: {yields} An integrated-scale toxicological model was used to examine the impact of Cd on rainbow trout. {yields} A probabilistic assessment model was performed to estimate Cd susceptibility risk. {yields} An elimination-detoxification-recovery scheme was constructed to enhance the model predictive ability. {yields} Gut had a relative lower Cd susceptibility risk than that in gill and liver.

  14. 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.

  15. Identification of the cause of weak acute toxicity to rainbow trout at a petroleum refinery

    International Nuclear Information System (INIS)

    Arnold, W.R.; Zaleski, R.T.; Biddinger, G.R.

    1995-01-01

    The refinery in question performs flow through acute toxicity tests on its effluent four times per month using three fish species: fathead minnows (Pimephales promelas), threespine sticklebacks (Gasterosteus oculeatus) and rainbow trout (Oncorhynchus mykiss). Several months of monitoring data indicated a transient low level acute toxicity to rainbow trout. In most cases, several days were required for mortality to occur in the flow through tests and numerous attempts to reproduce toxicity in static and static renewal tests were unsuccessful. A decision was made to manipulate the effluent in an attempt to enhance the toxic effect in the static mode so that conventional methods could be used to identify the cause. these tests indicated that toxicity was pH dependent. Additional testing, using EPA's Phase 1 Toxicity Identification Evaluation methods suggested that the cause of toxicity was probably an organic acid. Experiments were subsequently begun to identify the specific cause and source of toxicity. This paper reviews the problems confronted during the various phases of the study and the decisions that were made that eventually led to an understanding of the basis of toxicity

  16. Degradation rate of praziquantel and fenbendazole in rainbow trout following oral administration.

    Science.gov (United States)

    Soukupova-Markova, Zdenka; Doubkova, Veronika; Marsalek, Petr; Svobodova, Zdenka; Papezikova, Ivana; Lang, Stepan; Navratil, Stanislav; Palikova, Miroslava

    2015-01-01

    The aim of this study was to evaluate and compare the rate of degradation and elimination of praziquantel and fenbendazole antiparasitics following oral administration to salmonids. In addition, we determine whether the length of the legal withdrawal period is sufficient for complete elimination of antiparasitic residue from the body. The use of these drugs in fish is currently considered off-label and data on degradation are not available for rainbow trout. The model species for this experiment was the rainbow trout (Oncorhynchus mykiss) and praziquantel and fenbendazole were chosen for experimental therapy. Both drugs were administered into the gastrointestinal tract using a stomach tube. Concentrations of fenbendazole and praziquantel were established through high performance liquid chromatography-tandem mass spectrometry. Our results show that concentrations of praziquantel and fenbendazole reach their maximum in the body within 24 hours of administration, with concentrations dropping sharply over the following 24 hours. With one exception, when trace amounts of both substances were found in blood plasma, the drugs were completely degraded and eliminated from the body by the end of the experiment (corresponding to 497.6 degree days). Praziquantel and fenbendazole both show a high rate of degradation and elimination from fish. As both substances were eliminated from the body within the required withdrawal period (i.e. within 500 degree days) they can be safely used based on current knowledge of their therapeutic effect for treating helminth infections.

  17. 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.

  18. 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

  19. Cell-mediated immune responses in rainbow trout after DNA immunization against the viral hemorrhagic septicemia virus

    DEFF Research Database (Denmark)

    Utke, Katrin; Kock, Holger; Schuetze, Heike

    2008-01-01

    injection site rather than to injection sites of heterologous vaccines, suggesting the antigen specificity of homing. By demonstrating CMC responses to distinct viral proteins and homing in rainbow trout, these results substantially contribute to the understanding of the teleost immune system.......To identify viral proteins that induce cell-mediated cytotoxicity (CMC) against viral hemorrhagic septicemia virus (VHSV)-infected cells, rainbow trout were immunized with DNA vectors encoding the glycoprotein G or the nucleocapsid protein N of VHSV. The G protein was a more potent trigger...... of cytotoxic cells than the N protein. Peripheral blood leukocytes (PBL) isolated from trout immunized against the G protein killed both VHSV-infected MHC class I matched (RTG-2) and VHSV-infected xenogeneic (EPC) target cells, suggesting the involvement of both cytotoxic T lymphocytes (CTL) and NK cells...

  20. 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.

  1. Effects of dietary cadmium exposure on tissue-specific cadmium accumulation, iron status and expression of iron-handling and stress-inducible genes in rainbow trout: Influence of elevated dietary iron

    International Nuclear Information System (INIS)

    Kwong, Raymond W.M.; Andres, Jose A.; Niyogi, Som

    2011-01-01

    Recent evidences suggest that dietary cadmium (Cd) uptake likely occurs via the dietary iron (Fe) uptake pathway in freshwater fish, at least in part. The present study investigated the interactive effects of dietary Cd and Fe in juvenile rainbow trout (Oncorhynchus mykiss). Fish were treated for four weeks with four different diets: normal Fe, high Fe, normal Fe plus Cd, and high Fe plus Cd. Physiological parameters, tissue-specific Fe and Cd level, plasma Fe status, and tissue-specific mRNA expression of transferrin, metallothioneins (MT-A and MT-B) and heat shock proteins 70 (HSP70a and HSP70b) were analyzed. Exposure to dietary Cd increased Cd burden in the following order: intestine > kidney > stomach > liver > gill > carcass. Interestingly, high dietary Fe reduced Cd accumulation in the stomach and intestine as well as in the wholebody of fish. Dietary Cd increased hepatic transferrin mRNA expression and total Fe binding capacity in the plasma, indicating the effect of Cd on Fe handling in fish. The mRNA expression of MTs and HSP70s was also increased in various tissues following dietary Cd exposure, however the response profile of different MT and HSP70 genes was not consistent among different tissues. In general, MT-A was more responsive to Cd exposure in the intestine and liver, whereas MT-B was more responsive in the kidney. Similarly, HSP70a expression was more sensitive to Cd exposure than HSP70b, particularly in the intestine. Interestingly, high Fe diet suppressed Cd-induced induction of transferrin, MT and HSP70 genes in various tissues. Overall, our study suggests that elevated dietary Fe can reduce Cd accumulation and ameliorate Cd-induced stress responses in freshwater fish.

  2. Effects of dietary cadmium exposure on tissue-specific cadmium accumulation, iron status and expression of iron-handling and stress-inducible genes in rainbow trout: Influence of elevated dietary iron

    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)

    2011-03-15

    Recent evidences suggest that dietary cadmium (Cd) uptake likely occurs via the dietary iron (Fe) uptake pathway in freshwater fish, at least in part. The present study investigated the interactive effects of dietary Cd and Fe in juvenile rainbow trout (Oncorhynchus mykiss). Fish were treated for four weeks with four different diets: normal Fe, high Fe, normal Fe plus Cd, and high Fe plus Cd. Physiological parameters, tissue-specific Fe and Cd level, plasma Fe status, and tissue-specific mRNA expression of transferrin, metallothioneins (MT-A and MT-B) and heat shock proteins 70 (HSP70a and HSP70b) were analyzed. Exposure to dietary Cd increased Cd burden in the following order: intestine > kidney > stomach > liver > gill > carcass. Interestingly, high dietary Fe reduced Cd accumulation in the stomach and intestine as well as in the wholebody of fish. Dietary Cd increased hepatic transferrin mRNA expression and total Fe binding capacity in the plasma, indicating the effect of Cd on Fe handling in fish. The mRNA expression of MTs and HSP70s was also increased in various tissues following dietary Cd exposure, however the response profile of different MT and HSP70 genes was not consistent among different tissues. In general, MT-A was more responsive to Cd exposure in the intestine and liver, whereas MT-B was more responsive in the kidney. Similarly, HSP70a expression was more sensitive to Cd exposure than HSP70b, particularly in the intestine. Interestingly, high Fe diet suppressed Cd-induced induction of transferrin, MT and HSP70 genes in various tissues. Overall, our study suggests that elevated dietary Fe can reduce Cd accumulation and ameliorate Cd-induced stress responses in freshwater fish.

  3. Fertilization capacity with rainbow trout DNA-damaged sperm and embryo developmental success.

    Science.gov (United States)

    Pérez-Cerezales, S; Martínez-Páramo, S; Beirão, J; Herráez, M P

    2010-06-01

    Mammalian spermatozoa undergo a strong selection process along the female tract to guarantee fertilization by good quality cells, but risks of fertilization with DNA-damaged spermatozoa have been reported. In contrast, most external fertilizers such as fish seem to have weaker selection procedures. This fact, together with their high prolificacy and external embryo development, indicates that fish could be useful for the study of the effects of sperm DNA damage on embryo development. We cryopreserved sperm from rainbow trout using egg yolk and low-density lipoprotein as additives to promote different rates of DNA damage. DNA fragmentation and oxidization were analyzed using comet assay with and without digestion with restriction enzymes, and fertilization trials were performed. Some embryo batches were treated with 3-aminobenzamide (3AB) to inhibit DNA repair by the poly (ADP-ribose) polymerase, which is an enzyme of the base excision repair pathway. Results showed that all the spermatozoa cryopreserved with egg yolk carried more than 10% fragmented DNA, maintaining fertilization rates of 61.1+/-2.3 but a high rate of abortions, especially during gastrulation, and only 14.5+/-4.4 hatching success. Furthermore, after 3AB treatment, hatching dropped to 3.2+/-2.2, showing that at least 10% DNA fragmentation was repaired. We conclude that trout sperm maintains its ability to fertilize in spite of having DNA damage, but that embryo survival is affected. Damage is partially repaired by the oocyte during the first cleavage. Important advantages of using rainbow trout for the study of processes related to DNA damage and repair during development have been reported.

  4. Effect of DHA supplementation on digestible starch utilization by rainbow trout.

    Science.gov (United States)

    Tapia-Salazar, M; Bureau, W; Panserat, S; Corraze, G; Bureau, D P

    2006-01-01

    Rainbow trout has a limited ability to utilize digestible carbohydrates efficiently. Trout feeds generally contain high levels of DHA, a fatty acid known to inhibit a number of glycolytic and lipogenic enzymes in animals. A study was conducted to determine whether carbohydrate utilization by rainbow trout might be affected by dietary DHA level. Two low-carbohydrate (digestible carbohydrate) basal diets were formulated to contain 1 (adequate) or 4 (excess) g/100 g DHA diet respectively. The two basal diets were diluted with increasing levels of digestible starch (0 %, 10 %, 20 % and 30 %, respectively) to produce eight diets. These diets were fed to fish for 12 weeks at 15 degrees C according to a pair-fed protocol that consisted of feeding the same amount of basal diet but different amounts of starch. Live weight, N and lipid gains, hepatic glycogen and plasma glucose values significantly increased, whereas feed efficiency (gain:feed) significantly decreased, with increasing starch intake (Pdigestible N intake) improved with starch supplementation but was not affected by DHA level (P>0.05). Starch increased the activity of glucokinase, pyruvate kinase, glucose 6-phosphate dehydrogenase and fatty acid synthase (P<0.05) but did not affect hexokinase and malic enzyme activity. DHA had no effect on growth but increased plasma glucose and reduced carcass lipid and liver glycogen contents (P<0.05). Glycolytic and lipogenic enzymes were not affected by DHA level, except for pyruvate kinase, which was reduced by increasing DHA level. These results suggest only a marginal effect of dietary DHA on the ability of fish to utilize carbohydrate.

  5. Ethoxyresorufin-O-deethylase (EROD) induction in rainbow trout exposed to diluted oil sand wastewater

    International Nuclear Information System (INIS)

    Verbeek, A.; Mackay, W.; Birkholz, D.

    1995-01-01

    Toxic industrial wastewaters, such as those from oil sands extraction, must be assessed for their potential sublethal effects before they can be safely disposed in the environment. The induction of ethoxyresorufin-O-deethylase activity was assessed as a potential bioindicator of sublethal stress in rainbow trout exposed to sublethal concentrations of oil sands tailings water. The mixed-function oxygenase system in rainbow trout responded rapidly following a definable concentration-response relationship; however, it proved to be a relatively insensitive indicator of sublethal exposure to oil sands tailings water. Increased activity and maximal induction, as a result of exposure to 0.3 and 0.6 times the LC 50 (Toxic Units), occurred rapidly within 24 hours of exposure. The linearity of the relationship between the concentration of oil sands tailings pond water and ethoxyresorufin-O-deethylase activity, expressed by the following regression equation, In EROD = 3.68 (conc.) + 3.20, had an r 2 value of 0.593. Maximal induction required 0.4--0.8 Toxic Units. The absolute level of maximal induction was only one-fifth to one-sixth of the potential induction as found in response to the positive control, 0.5 mg/kg β-naphthoflavone (i.p.). The authors also present data that suggests that the different levels of induction observed in trout exposed to tailings pond water vs those injected with 0.5 mg/kg β-naphthoflavone (i.p.) may be indicative of two different P450 isoforms, the CYP4Al isoform responding to the organic acidic surfactants in oil sands tailings pond water and the CYP1A1 isoform, the isoform generally associated with most xenobiotic transformation in fish, responding to β-naphthoflavone

  6. Effect of replacement of fish meal by potato protein concentrate in the diet for rainbow trout on feeding rate, digestibility and growth

    DEFF Research Database (Denmark)

    Xie, Shougi; Jokumsen, Alfred

    1999-01-01

    Six isonitrogenous and isoenergetic diets were composed to investigate the effects of incorporation of potato protein concentrate (PPC) and supplementation of methionine in the diet for rainbow trout (Oncorhynchus mykiss) on feeding rate, digestion, growth, feed utilization and body composition. ...

  7. 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...

  8. Acid-base balance in rainbow trout (Salmo gairdneri) subjected to acid stresses

    Energy Technology Data Exchange (ETDEWEB)

    Eddy, F.B.

    1976-01-01

    The respiratory properties of rainbow-trout blood were investigated in acid-stressed fish. In the first group acid was introduced into the bloodstream and in the second the carbon dioxide content of the ambient water was increased. Initially the introduction of the acid to the blood caused a decrease in blood pH and bicarbonate, and increases in oxygen uptake and ventilation volume. After 2 to 3 h these values had returned to the control levels. Trout subjected to high ambient CO/sub 2/ (about 10 mmHg) showed a decrease in blood pH while PCO/sub 2/ and bicarbonate increased. After 8 h the trout began to show signs of compensation to the acidosis. In each experiment the blood PO/sub 2/ was little changed but blood O/sub 2/ content was decreased and tended not to resume the control value even after several hours. The results are discussed in terms of the various acid-base mechanisms thought to be available to the fish. These include branchial ion exchanges and the possible buffering roles of the extracellular and intracellular fluids.

  9. 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.

  10. 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.

  11. Disposition of naphthalene and its metabolites in the brain of rainbow trout (Salmo gairdneri)

    International Nuclear Information System (INIS)

    Collier, T.K.; Krahn, M.M.; Malins, D.C.

    1980-01-01

    Rainbow trout (Salmo gairdneri) were exposed to orally administered [ 3 H]naphthalene. Another group received naphthyl glucuronic acid and naphthyl sulfate via iv injection. Brain, liver, and blood were assayed for the parent compound and/or total metabolites. Individual naphthalene derivatives were determined by high-performance liquid chromatography (hplc) using either radiometric or on-line fluorimetric detection systems. Naphthalene concentrations in brain (8.2 pmol/mg dry wt at 16 hr after feeding) approximated those found at the same time in liver (7.4 pmol/mg dry wt). A nonconjugated naphthalene derivative, 1,2-dihydro-1,2-dihydroxynaphthalene, also accumulated in brain (0.041 pmol/mg dry wt after 16 hr), although to a lesser degree than in liver (0.10 pmol/mg dry wt after 16 hr). Conjugated naphthalene derivatives, 1-naphthyl sulfate and 1-naphthyl glucuronic acid, although present in liver and blood, were largely excluded from the brain. Low naphthalene hydroxylase activity (<2.0 pmol product formed/mg protein/min) indicated that the trout brain has a minimal ability to oxidize aromatic hydrocarbons. These findings suggest that the brain of adult trout is substantially different from other tissues (e.g., liver and blood) with respect to the disposition of naphthalene and its metabolites

  12. Dietary acidification enhances phosphorus digestibility but decreases H+/K+-ATPase expression in rainbow trout.

    Science.gov (United States)

    Sugiura, Shozo H; Roy, Prabir K; Ferraris, Ronaldo P

    2006-10-01

    Oxynticopeptic cells of fish stomach are thought to secrete less acid than the specialized parietal cells of mammalian stomach. Gastric acidity, however, has not been directly compared between fish and mammals. We therefore fed rainbow trout and rats the same meal, and found that the lowest postprandial pH of trout stomach was 2.7, which was only transiently sustained for 1 h, whereas that of rat stomach was 1.3, which was sustained for 3 h. Postprandial pH of the small intestine was slightly higher in trout (approximately 8.0) than in rats (approximately 7.6), but pH of the large intestine was similar (approximately 8.0). Addition of acids to fish feeds, in an attempt to aid the weak acidity of fish stomach, has been known to improve phosphorus digestibility, but its physiological effect on fish stomach is not known. Exogenous acids did improve phosphorus digestibility but also decreased steady-state mRNA expression of trout H(+)/K(+)-ATPase (ATP4A, the proton pump) as well as Na(+)/bicarbonate cotransporter (NBC), and had no effect on gastrin-like mRNA and somastostatin (SST) mRNA abundance. Gastrin-like mRNA and SST-2 mRNA were equally distributed between corpus and antrum. ATP4A mRNA and NBC mRNA were in the corpus, whereas SST-1 mRNA was in the antrum. Trout gastrin-like EST had modest homology to halibut and pufferfish gastrin, whereas trout ATP4A mRNA had > or = 95% amino acid homology with mammalian, Xenopus and flounder ATP4A. Although ATP4A seems highly conserved among vertebrates, gastric acidity is much less in trout than in rats, explaining the low digestibility of bone phosphorus, abundant in fish diets. Dietary acidification does not reduce acidity enough to markedly improve phosphorus digestibility, perhaps because exogenous acids may inhibit endogenous acid production.

  13. 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.

  14. Simultaneous effect of initial weight, initial crowding, temperature and O2 concentration on the nutritional use of food by rainbow trout (Oncorhynchus mykiss).

    Science.gov (United States)

    Martinez, F J; Garcia, M P; Canteras, M; De Costa, J; Zamora, S

    1992-01-01

    The simultaneous effects of initial weight, initial crowding, temperature and O2 concentration on the following ratios: relative growth rate percent (RGRP), feed efficiency (FE), protein efficiency ratio (PER) and protein productive value (PPV) were studied in the rainbow trout. Multivariant equations were obtained for each of the mentioned indices. The joint effects of these factors were evidenced by means of a multiple correlation analysis. The influence of temperature and, to a lesser extent, of crowding, and O2 concentration on the nutritional use of food by the trout was demonstrated, their fundamental dependence on factors extrinsic to the animal being underlined. The non proportional changes in PER and PPV as temperature rises revealed that an increasing part of the ingested aminoacids were used for synthesis of fat, non for proteins edification.

  15. Molecular cloning and functional characterization of a rainbow trout liver Oatp

    International Nuclear Information System (INIS)

    Steiner, Konstanze; Hagenbuch, Bruno; Dietrich, Daniel R.

    2014-01-01

    Cyanobacterial blooms have an impact on the aquatic ecosystem due to the production of toxins (e.g. microcystins, MCs), which constrain fish health or even cause fish death. However the toxicokinetics of the most abundant toxin, microcystin-LR (MC-LR), are not yet fully understood. To investigate the uptake mechanism, the novel Oatp1d1 in rainbow trout (rtOatp1d1) was cloned, identified and characterized. The cDNA isolated from a clone library consisted of 2772 bp containing a 2115 bp open reading frame coding for a 705 aa protein with an approximate molecular mass of 80 kDa. This fish specific transporter belongs to the OATP1 family and has most likely evolved from a common ancestor of OATP1C1. Real time PCR analysis showed that rtOatp1d1 is predominantly expressed in the liver, followed by the brain while expression in other organs was not detectable. Transient transfection in HEK293 cells was used for further characterization. Like its human homologues OATP1A1, OATP1B1 and OATP1B3, rtOatp1d1 displayed multi-specific transport including endogenous and xenobiotic substrates. Kinetic analyses revealed a K m value of 13.9 μM and 13.4 μM for estrone-3-sulfate and methotrexate, respectively and a rather low affinity for taurocholate with a K m value of 103 μM. Furthermore, it was confirmed that rtOatp1d1 is a MC-LR transporter and therefore most likely plays a key role in the susceptibility of rainbow trout to MC intoxications. - Highlights: • A new Oatp1d1 in rainbow trout (rtOatp1d1) was cloned, identified and characterized. • rtOatp1d1 is predominantly expressed in the liver. • rtOatp1d1 displays multi-specific transport of endogenous and xenobiotic substrates. • rtOatp1d1 is a homologue of the OATP1A1, OATP1B1 and OATP1B3. • rtOatp1d1 is a microcystin (MC) transporter

  16. Molecular cloning and functional characterization of a rainbow trout liver Oatp

    Energy Technology Data Exchange (ETDEWEB)

    Steiner, Konstanze, E-mail: konstanze.steiner@uni-konstanz.de [University of Konstanz, Human- and Environmental Toxicology, 78464 Konstanz (Germany); Hagenbuch, Bruno, E-mail: bhagenbuch@kumc.edu [Pharmacology, Toxicology and Therapeutics, The University of Kansas Medical Center, Kansas City 66160, KS (United States); Dietrich, Daniel R., E-mail: daniel.dietrich@uni-konstanz.de [University of Konstanz, Human- and Environmental Toxicology, 78464 Konstanz (Germany)

    2014-11-01

    Cyanobacterial blooms have an impact on the aquatic ecosystem due to the production of toxins (e.g. microcystins, MCs), which constrain fish health or even cause fish death. However the toxicokinetics of the most abundant toxin, microcystin-LR (MC-LR), are not yet fully understood. To investigate the uptake mechanism, the novel Oatp1d1 in rainbow trout (rtOatp1d1) was cloned, identified and characterized. The cDNA isolated from a clone library consisted of 2772 bp containing a 2115 bp open reading frame coding for a 705 aa protein with an approximate molecular mass of 80 kDa. This fish specific transporter belongs to the OATP1 family and has most likely evolved from a common ancestor of OATP1C1. Real time PCR analysis showed that rtOatp1d1 is predominantly expressed in the liver, followed by the brain while expression in other organs was not detectable. Transient transfection in HEK293 cells was used for further characterization. Like its human homologues OATP1A1, OATP1B1 and OATP1B3, rtOatp1d1 displayed multi-specific transport including endogenous and xenobiotic substrates. Kinetic analyses revealed a K{sub m} value of 13.9 μM and 13.4 μM for estrone-3-sulfate and methotrexate, respectively and a rather low affinity for taurocholate with a K{sub m} value of 103 μM. Furthermore, it was confirmed that rtOatp1d1 is a MC-LR transporter and therefore most likely plays a key role in the susceptibility of rainbow trout to MC intoxications. - Highlights: • A new Oatp1d1 in rainbow trout (rtOatp1d1) was cloned, identified and characterized. • rtOatp1d1 is predominantly expressed in the liver. • rtOatp1d1 displays multi-specific transport of endogenous and xenobiotic substrates. • rtOatp1d1 is a homologue of the OATP1A1, OATP1B1 and OATP1B3. • rtOatp1d1 is a microcystin (MC) transporter.

  17. 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.

  18. Cardiorespiratory upregulation during seawater acclimation in rainbow trout: effects on gastrointestinal perfusion and postprandial responses.

    Science.gov (United States)

    Brijs, Jeroen; Gräns, Albin; Ekström, Andreas; Olsson, Catharina; Axelsson, Michael; Sandblom, Erik

    2016-05-01

    Increased gastrointestinal blood flow is essential for euryhaline fishes to maintain osmotic homeostasis during the initial phase of a transition from freshwater to seawater. However, the cardiorespiratory responses and hemodynamic changes required for a successful long-term transition to seawater remain largely unknown. In the present study, we simultaneously measured oxygen consumption rate (ṀO2), cardiac output (CO), heart rate (HR), and gastrointestinal blood flow (GBF) in rainbow trout (Oncorhynchus mykiss) acclimated to either freshwater or seawater for at least 6 wk. Seawater-acclimated trout displayed significantly elevated ṀO2 (day: 18%, night: 19%), CO (day: 22%, night: 48%), and GBF (day: 96%, night: 147%), demonstrating that an overall cardiorespiratory upregulation occurs during seawater acclimation. The elevated GBF was achieved via a combination of increased CO, mediated through elevated stroke volume (SV), and a redistribution of blood flow to the gastrointestinal tract. Interestingly, virtually all of the increase in CO of seawater-acclimated trout was directed to the gastrointestinal tract. Although unfed seawater-acclimated trout displayed substantially elevated cardiorespiratory activity, the ingestion of a meal resulted in a similar specific dynamic action (SDA) and postprandial GBF response as in freshwater-acclimated fish. This indicates that the capacity for the transportation of absorbed nutrients, gastrointestinal tissue oxygen delivery, and acid-base regulation is maintained during digestion in seawater. The novel findings presented in this study clearly demonstrate that euryhaline fish upregulate cardiovascular function when in seawater, while retaining sufficient capacity for the metabolic and cardiovascular changes associated with the postprandial response. Copyright © 2016 the American Physiological Society.

  19. 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.

  20. Lake Roosevelt Rainbow Trout Habitat/Passage Improvement Project, Annual Report 2002-2003.

    Energy Technology Data Exchange (ETDEWEB)

    Sears, Sheryl

    2004-01-01

    The construction of Chief Joseph and Grand Coulee Dams completely and irrevocably blocked anadromous fish migrations to the Upper Columbia River. Historically this area hosted vast numbers of salmon returning to their natal waters to reproduce and die. For the native peoples of the region, salmon and steelhead were a principle food source, providing physical nourishment and spiritual sustenance, and contributing to the religious practices and the cultural basis of tribal communities. The decaying remains of spawned-out salmon carcasses contributed untold amounts of nutrients into the aquatic, aerial, and terrestrial ecosystems of tributary habitats in the upper basin. Near the present site of Kettle Falls, Washington, the second largest Indian fishery in the state existed for thousands of years. Returning salmon were caught in nets and baskets or speared on their migration to the headwater of the Columbia River in British Columbia. Catch estimates at Kettle Falls range from 600,000 in 1940 to two (2) million around the turn of the century (UCUT, Report No.2). The loss of anadromous fish limited the opportunities for fisheries management and enhancement exclusively to those actions addressed to resident fish. The Lake Roosevelt Rainbow Trout Habitat/Passage Improvement Project is a mitigation project intended to enhance resident fish populations and to partially mitigate for anadromous fish losses caused by hydropower system impacts. This substitution of resident fish for anadromous fish losses is considered in-place and out-of-kind mitigation. Upstream migration and passage barriers limit the amount of spawning and rearing habitat that might otherwise be utilized by rainbow trout. The results of even limited stream surveys and habitat inventories indicated that a potential for increased natural production exists. However, the lack of any comprehensive enhancement measures prompted the Upper Columbia United Tribes Fisheries Center (UCUT), Colville Confederated

  1. Lake Roosevelt Rainbow Trout Habitat/Passage Improvement Project, Annual Report 2001-2002.

    Energy Technology Data Exchange (ETDEWEB)

    Sears, Sheryl

    2003-01-01

    The construction of Chief Joseph and Grand Coulee Dams completely and irrevocably blocked anadromous fish migrations to the Upper Columbia River. Historically this area hosted vast numbers of salmon returning to their natal waters to reproduce and die. For the native peoples of the region, salmon and steelhead were a principle food source, providing physical nourishment and spiritual sustenance, and contributing to the religious practices and the cultural basis of tribal communities. The decaying remains of spawned-out salmon carcasses contributed untold amounts of nutrients into the aquatic, aerial, and terrestrial ecosystems of tributary habitats in the upper basin. Near the present site of Kettle Falls, Washington, the second largest Indian fishery in the state existed for thousands of years. Returning salmon were caught in nets and baskets or speared on their migration to the headwater of the Columbia River in British Columbia. Catch estimates at Kettle Falls range from 600,000 in 1940 to two (2) million around the turn of the century (UCUT, Report No.2). The loss of anadromous fish limited the opportunities for fisheries management and enhancement exclusively to those actions addressed to resident fish. The Lake Roosevelt Rainbow Trout Habitat/Passage Improvement Project is a mitigation project intended to enhance resident fish populations and to partially mitigate for anadromous fish losses caused by hydropower system impacts. This substitution of resident fish for anadromous fish losses is considered in-place and out-of-kind mitigation. Upstream migration and passage barriers limit the amount of spawning and rearing habitat that might otherwise be utilized by rainbow trout. The results of even limited stream surveys and habitat inventories indicated that a potential for increased natural production exists. However, the lack of any comprehensive enhancement measures prompted the Upper Columbia United Tribes Fisheries Center (UCUT), Colville Confederated

  2. 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.

  3. Cadmium-mediated disruption of cortisol biosynthesis involves suppression of corticosteroidogenic genes in rainbow trout

    International Nuclear Information System (INIS)

    Sandhu, Navdeep; Vijayan, Mathilakath M.

    2011-01-01

    Cadmium is widely distributed in the aquatic environment and is toxic to fish even at sublethal concentrations. This metal is an endocrine disruptor, and one well established role in teleosts is the suppression of adrenocorticotrophic hormone (ACTH)-stimulated cortisol biosynthesis by the interrenal tissue. However the mechanism(s) leading to this steroid suppression is poorly understood. We tested the hypothesis that cadmium targets genes encoding proteins critical for corticosteroid biosynthesis, including melanocortin 2 receptor (MC2R), steroidogenic acute regulatory protein (StAR) and cytochrome P450 side chain cleavage enzyme (P450scc), in rainbow trout (Oncorhynchus mykiss). To test this, head kidney slices (containing the interrenal tissues) were incubated in vitro with cadmium chloride (0, 10, 100 and 1000 nM) for 4 h either in the presence or absence of ACTH (0.5 IU/mL). In the unstimulated head kidney slices, cadmium exposure did not affect basal cortisol secretion and the mRNA levels of MC2R and P450scc, while StAR gene expression was significantly reduced. Cadmium exposure significantly suppressed ACTH-stimulated cortisol production in a dose-related fashion. This cadmium-mediated suppression in corticosteroidogenesis corresponded with a significant reduction in MC2R, StAR and P450scc mRNA levels in trout head kidney slices. The inhibition of ACTH-stimulated cortisol production and suppression of genes involved in corticosteroidogenesis by cadmium were completely abolished in the presence of 8-Bromo-cAMP (a cAMP analog). Overall, cadmium disrupts the expression of genes critical for corticosteroid biosynthesis in rainbow trout head kidney slices. However, the rescue of cortisol production as well as StAR and P450scc gene expressions by cAMP analog suggests that cadmium impact occurs upstream of cAMP production. We propose that MC2R signaling, the primary step in ACTH-induced cortocosteroidogenesis, is a key target for cadmium-mediated disruption of

  4. Cadmium-mediated disruption of cortisol biosynthesis involves suppression of corticosteroidogenic genes in rainbow trout

    Energy Technology Data Exchange (ETDEWEB)

    Sandhu, Navdeep [Department of Biology, University of Waterloo, 200 University Avenue West, Waterloo, Ontario N2L 3G1 (Canada); Vijayan, Mathilakath M., E-mail: mvijayan@uwaterloo.ca [Department of Biology, University of Waterloo, 200 University Avenue West, Waterloo, Ontario N2L 3G1 (Canada)

    2011-05-15

    Cadmium is widely distributed in the aquatic environment and is toxic to fish even at sublethal concentrations. This metal is an endocrine disruptor, and one well established role in teleosts is the suppression of adrenocorticotrophic hormone (ACTH)-stimulated cortisol biosynthesis by the interrenal tissue. However the mechanism(s) leading to this steroid suppression is poorly understood. We tested the hypothesis that cadmium targets genes encoding proteins critical for corticosteroid biosynthesis, including melanocortin 2 receptor (MC2R), steroidogenic acute regulatory protein (StAR) and cytochrome P450 side chain cleavage enzyme (P450scc), in rainbow trout (Oncorhynchus mykiss). To test this, head kidney slices (containing the interrenal tissues) were incubated in vitro with cadmium chloride (0, 10, 100 and 1000 nM) for 4 h either in the presence or absence of ACTH (0.5 IU/mL). In the unstimulated head kidney slices, cadmium exposure did not affect basal cortisol secretion and the mRNA levels of MC2R and P450scc, while StAR gene expression was significantly reduced. Cadmium exposure significantly suppressed ACTH-stimulated cortisol production in a dose-related fashion. This cadmium-mediated suppression in corticosteroidogenesis corresponded with a significant reduction in MC2R, StAR and P450scc mRNA levels in trout head kidney slices. The inhibition of ACTH-stimulated cortisol production and suppression of genes involved in corticosteroidogenesis by cadmium were completely abolished in the presence of 8-Bromo-cAMP (a cAMP analog). Overall, cadmium disrupts the expression of genes critical for corticosteroid biosynthesis in rainbow trout head kidney slices. However, the rescue of cortisol production as well as StAR and P450scc gene expressions by cAMP analog suggests that cadmium impact occurs upstream of cAMP production. We propose that MC2R signaling, the primary step in ACTH-induced cortocosteroidogenesis, is a key target for cadmium-mediated disruption of

  5. The amount of food ingested in a single meal by rainbow trout offered chopped herring, dry and wet diets

    Science.gov (United States)

    Ruohonen; Grove; McIlroy

    1997-07-01

    Two-year-old 1·5-kg rainbow trout were held in cages and conditioned by feeding either on low-fat chopped herring (H trout) or dry pellets (P trout) for 15 weeks. Their satiation amounts were then determined under standard conditions. On a wet weight basis H trout ate 2·5-3·5 times more food than P trout; this was sufficient to compensate for the high water content of herring and thereby maintain the dry matter intake. When P trout were offered herring (PH trout) they consumed more food than when offered dry pellets but not as much as H trout. Stomach capacity restricted the intake and their dry matter intake was reduced by c. 40%. When H trout were offered dry pellets (HP trout) they adjusted their intake immediately close to the level of P trout although their larger stomachs could have accommodated more than twice this volume of dry food. The return of appetite after a satiation meal was almost linear with time. Appetite increased at c. 556 mg g-1 body weight h-1 for H trout and at 142 mg g-1 bw h-1 for P trout. The return of appetite in PH trout was significantly slower (c. 370 mg g-1 bw h-1) than in H trout; the previous dietary history of the PH trout limited their capacity to process larger volumes of wet food in a single meal. Fish offered dry diet (P and HP trout) had similar rates of appetite return despite their previous feeding history suggesting that the property of the dry feed itself might limit meal size. The total gastric emptying time of diets of similar dry matter content (with and without large amounts of water) was similar, but the delay time before gastric emptying starts tended to be longer for dry diets. Dry pellets appear to impose a demand for water that prolongs the gastric delay. This water demand is met partly by drinking since the trout fed on dry pellets drank significantly more (436±189 mg kg-1 h-1) than unfed and herring-fed trout which drank little or not at all (65±113 and 70±66 mg kg-1 h-1 respectively). Dietary water

  6. 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

  7. Allometric scaling of hepatic biotransformation in rainbow trout

    Science.gov (United States)

    Biotransformation can markedly reduce the extent to which hydrophobic organic chemicals accumulate in fish. However, predicting the impacts of biotransformation on chemical accumulation is complicated by a number of factors, including the possible influence of differences in fis...

  8. Stress-related gene expression changes in rainbow trout hepatocytes exposed to various municipal wastewater treatment influents and effluents.

    Science.gov (United States)

    Gagné, F; Smyth, S A; André, C; Douville, M; Gélinas, M; Barclay, K

    2013-03-01

    The present study sought to examine the performance of six different wastewater treatment processes from 12 wastewater treatment plants using a toxicogenomic approach in rainbow trout hepatocytes. Freshly prepared rainbow trout hepatocytes were exposed to increasing concentrations of influent (untreated wastewaters) and effluent (C(18)) extracts for 48 h at 15 °C. A test battery of eight genes was selected to track changes in xenobiotic biotransformation, estrogenicity, heavy metal detoxification, and oxidative stress. The wastewaters were processed by six different treatment systems: facultative and aerated lagoons, activated sludge, biological aerated filter, biological nutrient removal, chemically assisted primary treated, and trickling filter/solids contact. Based on the chemical characteristics of the effluents, the treatment plants were generally effective in removing total suspended solids and chemical oxygen demand, but less so for ammonia and alkalinity. The 12 influents differed markedly with each other, which makes the comparison among treatment processes difficult. For the influents, both population size and flow rate influenced the increase in the following mRNA levels in exposed hepatocytes: metallothionein (MT), cytochrome P4503A4 (CYP3A4), and vitellogenin (VTG). Gene expression of glutathione S-transferase (GST) and the estrogen receptor (ER), were influenced only by population size in exposed cells to the influent extracts. The remaining genes-superoxide dismutase (SOD) and multidrug resistance transporter (MDR)-were not influenced by either population size or flow rate in exposed cells. It is noteworthy that the changes in MT, ER, and VTG in cells exposed to the effluents were significantly affected by the influents across the 12 cities examined. However, SOD, CYP1A1, CYP3A4, GST, and MDR gene expression were the least influenced by the incoming influents. The data also suggest that wastewater treatments involving biological or aeration

  9. Exposure to environmental levels of waterborne cadmium impacts corticosteroidogenic and metabolic capacities, and compromises secondary stressor performance in rainbow trout

    International Nuclear Information System (INIS)

    Sandhu, Navdeep; McGeer, James C.; Vijayan, Mathilakath M.

    2014-01-01

    Highlights: •Low level chronic waterborne cadmium exposure did not evoke a plasma cortisol response in rainbow trout. •Chronic cadmium exposure increases liver and gill metabolic capacities. •Chronic cadmium exposure disrupts head kidney steroidogenic capacity. •Chronic cadmium exposure disrupts glucocorticoid and mineralocorticoid receptor protein expressions in target tissues. •Chronic cadmium exposure compromises physiological performances to a secondary stressor in trout. -- Abstract: The physiological responses to waterborne cadmium exposure have been well documented; however, few studies have examined animal performances at low exposure concentrations of this metal. We tested the hypothesis that longer-term exposure to low levels of cadmium will compromise the steroidogenic and metabolic capacities, and reduce the cortisol response to a secondary stressor in fish. To test this, juvenile rainbow trout (Oncorhynchus mykiss) were exposed to 0 (control), 0.75 or 2.0 μg/L waterborne cadmium in a flow-through system and were sampled at 1, 7 and 28 d of exposure. There were only very slight disturbances in basal plasma cortisol, lactate or glucose levels in response to cadmium exposure over the 28 d period. Chronic cadmium exposure significantly affected key genes involved in corticosteroidogenesis, including melanocortin 2 receptor, steroidogenic acute regulatory protein and cytochrome P450 side chain cleavage enzyme. At 28 d, the high cadmium exposure group showed a significant drop in the glucocorticoid receptor and mineralocorticoid receptor protein expressions in the liver and brain, respectively. There were also perturbations in the metabolic capacities in the liver and gill of cadmium-exposed trout. Subjecting these fish to a secondary handling disturbance led to a significant attenuation of the stressor-induced plasma cortisol, glucose and lactate levels in the cadmium groups. Collectively, although trout appears to adjust to subchronic exposure

  10. Exposure to environmental levels of waterborne cadmium impacts corticosteroidogenic and metabolic capacities, and compromises secondary stressor performance in rainbow trout

    Energy Technology Data Exchange (ETDEWEB)

    Sandhu, Navdeep [Department of Biology, University of Waterloo, Waterloo, Ontario N2L 3G1 (Canada); McGeer, James C. [Department of Biology, Wilfrid Laurier University, Waterloo, Ontario N2L 3C5 (Canada); Vijayan, Mathilakath M., E-mail: matt.vijayan@ucalgary.ca [Department of Biology, University of Waterloo, Waterloo, Ontario N2L 3G1 (Canada)

    2014-01-15

    Highlights: •Low level chronic waterborne cadmium exposure did not evoke a plasma cortisol response in rainbow trout. •Chronic cadmium exposure increases liver and gill metabolic capacities. •Chronic cadmium exposure disrupts head kidney steroidogenic capacity. •Chronic cadmium exposure disrupts glucocorticoid and mineralocorticoid receptor protein expressions in target tissues. •Chronic cadmium exposure compromises physiological performances to a secondary stressor in trout. -- Abstract: The physiological responses to waterborne cadmium exposure have been well documented; however, few studies have examined animal performances at low exposure concentrations of this metal. We tested the hypothesis that longer-term exposure to low levels of cadmium will compromise the steroidogenic and metabolic capacities, and reduce the cortisol response to a secondary stressor in fish. To test this, juvenile rainbow trout (Oncorhynchus mykiss) were exposed to 0 (control), 0.75 or 2.0 μg/L waterborne cadmium in a flow-through system and were sampled at 1, 7 and 28 d of exposure. There were only very slight disturbances in basal plasma cortisol, lactate or glucose levels in response to cadmium exposure over the 28 d period. Chronic cadmium exposure significantly affected key genes involved in corticosteroidogenesis, including melanocortin 2 receptor, steroidogenic acute regulatory protein and cytochrome P450 side chain cleavage enzyme. At 28 d, the high cadmium exposure group showed a significant drop in the glucocorticoid receptor and mineralocorticoid receptor protein expressions in the liver and brain, respectively. There were also perturbations in the metabolic capacities in the liver and gill of cadmium-exposed trout. Subjecting these fish to a secondary handling disturbance led to a significant attenuation of the stressor-induced plasma cortisol, glucose and lactate levels in the cadmium groups. Collectively, although trout appears to adjust to subchronic exposure

  11. Estimation of sodium uptake through the gill of the rainbow trout Salmo gairdneri

    Energy Technology Data Exchange (ETDEWEB)

    Gardaire, E.; Avella, M.; Isaia, J.; Bornancin, M.; Mayer-Gostan, N.

    1985-01-01

    Sodium exchanges through the gill epithelia were estimated in the rainbow trout, Salmo gairdneri, using the perfused head technique. The head tissues accumulate radioactivity. In addition there exists an extrabranchial entry of sodium, which is 20 times smaller than the branchial one. The study of the evolution of venous and arterial sodium specific activities as a function of time is necessary before flux measurements are achieved. Contrary to previous studies, an uptake at the primary lamella level is demonstrated. Uptake of sodium through the secondary lamellae can be measured rapidly while at least 30 min are needed for measurement of uptake through the primary lamellae. Chloride cells of the primary lamellae contribute to about 20% of the total sodium uptake.

  12. 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...

  13. 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...

  14. Pulse versus continuous peracetic acid applications: Effects on rainbow trout performance, biofilm formation and water quality

    DEFF Research Database (Denmark)

    Liu, Dibo; Straus, David L.; Pedersen, Lars-Flemming

    2017-01-01

    Peracetic acid (PAA) products are being introduced to aquaculture as sustainable disinfectants. Two strategies are used to apply PAA: high dose pulse applications, or low dose continuous application. In the present study, their impacts on fish health and water quality were investigated...... by ensuring better water quality....... in triplicate flow-through tanks stocked with rainbow trout. The gentler and shorter water cortisol increase measured along twice-per-week pulse applications of 1 mg L−1 PAA indicated a progressive adaptation of fish. In contrast, the continuous application of 0.2 mg L−1 PAA caused no stress to fish...

  15. The effect of low changes in radiation dose on the hatching data of rainbow trout

    International Nuclear Information System (INIS)

    Buehringer, H.; Kellermann, H.J.

    1993-01-01

    Radiation hormesis hypothesis refers to the occurrence of a biphasic dose-respond relationship in which higher doses cause an inhibitory effect and lower doses cause a stimulatory effect. By extrapolation of this thesis there could be suggested a radiation damage effect below normal background radiation doses. Rainbow trout eggs, which are very radiation sensitive, were fertilized and incubated in environments with abient radiation (Hamburg), increased doses of radiation and decreased level of radiation doses (ASSE II). Hatching data (incubation time, hatching time, hatching success, number and kind of malformations, length of larvae) were examined for a hormesis effect. Only in hatching success a statistically significant effect of radiation dose was noticeable. (orig.) [de

  16. 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...

  17. Flavobacterium plurextorum sp. nov. isolated from farmed rainbow trout (Oncorhyncus mykiss)

    OpenAIRE

    Zamora, Leydis; Fernández Garayzábal, José F.; Sánchez-Porro Álvarez, Cristina; Palacios, Maria Ángel; Moore, Edward R. B.; Domínguez, Lucas; Ventosa Ucero, Antonio; Vela, Ana I.

    2013-01-01

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

  18. Histochemical distribution of zinc in the brain of the rainbow trout, Oncorhynchos myciss. I. The telencephalon

    DEFF Research Database (Denmark)

    Piñuela, C; Baatrup, E; Geneser, F A

    1992-01-01

    was mainly confined to the neuropil, but both moderately and intensely stained nerve cell bodies were of common occurrence. Stained fibers were never observed. The staining revealed a specific distribution pattern which could easily be correlated with the telencephalic nuclei defined on the basis......The present paper which describes the distribution of zinc in the telencephalon of the rainbow trout, Oncorhynchos myciss, is the first report on the distribution of a heavy metal in the fish brain. Zinc was demonstrated histochemically by silver enhancement using the Neo-Timm method. The staining...... of cytoarchitectural features. However, the telencephalon stained much more weakly than the rest of the brain, in striking contrast to the situation in the reptilian, mammalian, and avian brain. In these classes, high staining intensities are observed almost exclusively in the telencephalon. The staining...

  19. Egg cortisol exposure enhances fearfulness in larvae and juvenile rainbow trout

    DEFF Research Database (Denmark)

    Colson, Violaine; Valotaire, Claudiane; Geffroy, Benjamin

    2015-01-01

    We investigated the effects of an early boost of cortisol exposure in rainbow trout (Oncorhynchus mykiss) eggs during fertilisation on subsequent behavioural responses when exposed to a sudden stimulus in larvae and juveniles. At 55 d post-fertilisation (dpf), treatment had no effect on high...... accelerations occurring after a sudden event. At 146 dpf, these high accelerations were more frequent in cortisol-treated fish than in controls. At 146 dpf also, swimming activity was increased in cortisol-treated fish both before and after the sudden stimulus. This study underlines the important behavioural...... modifications in both larvae and juveniles, linked to a change in the surrounding environment of the embryo. Indeed, fish exposed to cortisol as eggs showed a higher level of fearfulness later in life. Our findings are of major interest for stress management in an aquaculture context and also allow for a better...

  20. Lower brain levels of serotonin in rainbow trout larvae with a propensity for social dominance

    DEFF Research Database (Denmark)

    Höglund, Erik; Åberg Andersson, Madelene

    performed on socially naive animals, predisposed to different levels of aggression, are needed to investigate to which extent inherited differences in 5-HTergic transmission underlie this behavioral variability. In this work we show that rainbow trout larvae, having a large yolk during emergence from......There is general consensus that low levels of brain serotonin are associated with aggression and social dominance. However, most of the studies investigating the relationship between serotonin (5-HT) and aggressive behavior have been performed in animals with previous social experience. Studies...... the spawning nests, also have higher probability to become social dominant. Furthermore, newly emerged socially naïve individuals with larger yolk also had lower brain 5-HT levels. This demonstrates a propensity to social dominance, which is associated with lower brain serotonin levels, in larvae that emerge...

  1. Variation in sensory profile between individual Rainbow trout from the same production batch

    DEFF Research Database (Denmark)

    Hyldig, Grethe; Green-Petersen, Ditte

    The variation in sensory properties between individual Rainbow trout (Oncorhynchus mykiss) belonging to the same aquaculture production batch was explored by using objective sensory profiling on minced and heat treated fillets. Additionally, Quality Index, mechanical texture, pH, fat and water...... content were measured. 30 fish, all from the same production batch, were sampled at three different times making three groups (ten fish each time). The results showed differences in the sensory profile between individual fish within all three groups. Also sensory differences between the three groups...... of fish were found. Similar differences in mechanical texture were found between individuals in two of the three groups and between the groups. No differences were found in Quality Index neither between individuals nor groups. A significant correlation between lipid content and firm texture was observed...

  2. 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...

  3. 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.

  4. 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.

  5. Effect of chlorine toxicity on certain blood parameters of adult rainbow trout (Salmo gairdneri)

    Energy Technology Data Exchange (ETDEWEB)

    Zeitoun, I.H.

    1977-01-01

    In an effort to assess the mode of chlorine action on rainbow trout (Salmo gairdneri), hematocrit percentage, and hemoglobin, methemoglobin, reduced glutathione, plasma protein, and plasma hemoglobin concentrations were determined in four tests in which duplicate groups of approximately 15 fish each were exposed to 3.86, 2.47, 2.75, and 1.09 mq l/sup -1/ TRCl/sub 2/ for 8, 19, 20, and 29 minutes, respectively. Blood from fish exposed to chlorine was darker and thicker than that of the control. Chlorine seemed to diffuse readily through the gills, oxidizing the hemoglobin to methemoglobin and disrupting the erythrocyte membranes, resulting in hemolysis. Stress polycythemia was also due to the substantial increase of the hematocrit values and hemoglobin concentration. Hemoconcentration led to a significant rise in the reduced glutathione and plasma protein concentrations. The hemoconcentration seemed to interfere with the blood circulation and hinder the delivery of oxygen to tissues.

  6. 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.

  7. 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.

  8. 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.

  9. 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...

  10. Virulence of viral haemorrhagic septicaemia virus (VHSV) genotype III in rainbow trout

    DEFF Research Database (Denmark)

    Ito, Takafumi; Kurita, Jun; Mori, Koh-Ichiro

    2016-01-01

    with the genotype III VHSV isolate 4p168 for 1 and 6 h. The viral titre in organs from fish challenged with NO-2007-50-385 for 6 h increased more rapidly than those exposed for 1 h. By in vitro studies it was demonstrated that the final titres of VHSV DK-3592B (GI), NO-2007-50-385 and 4p168 inoculated on EPC cells...... were very similar, whereas when inoculated on the rainbow trout cell line RTG-2 the titre of the non-virulent 4p168 isolate was 3-4 logs below the two other VHSV isolates. Based on a comparative analysis of the entire genome of the genotype III isolates, we suggest that substitutions of amino acids...

  11. Investigation of Detectability of Elementary Composition of Rainbow trout muscle with EDS (Energy Dispersive Spectroscopy Method

    Directory of Open Access Journals (Sweden)

    Saltuk Buğrahan CEYHUN

    2017-06-01

    Full Text Available In present study, it is investigated that detectability of elementary composition of rainbow trout muscle using Energy Dispersive Spectroscopy (EDS. EDS system which has worked with attached to scanning electron microscope can do qualitative and semi-quantitative elementary analyses on selected region of sample using characteristic X-rays. For this purpose, it was performed four point and two mapping analyses from four samples. According to results, it was detected 13 elements which are consist of C, N and O in 87.70 percentage. As a result, although the method is sensitive and reliable, it is concluded that not adequate for elemental analysis alone but can be used as a support for analyzes with systems such as especially atomic absorption and ICP-MS.

  12. Solid and suspended/dissolved waste (N, P, O) from rainbow trout (Oncorynchus mykiss)

    DEFF Research Database (Denmark)

    Dalsgaard, Anne Johanne Tang; Pedersen, Per Bovbjerg

    2011-01-01

    differences between the dietary treatment groups in the waste produced. On average, 48% of the ingestedNwas recovered in thewater (TANconstituting 64–79%of this)and7% inthesolids. In comparison, 1% of the ingested P was recovered in the water and 43% in the solids. A breakpoint value of 5.6 g standardized......Quantifying aquaculture waste into different waste fractions will make it possible to design different treatment setups for obtaining specific cleaning objectives. The aim of this study was therefore to measure “all” solid and suspended/dissolved (i.e. unsedimented) waste from juvenile rainbow...... trout (Oncorynchus mykiss) fed three commonly applied commercial diets, “all” waste referring to: total nitrogen (N), total ammonia nitrogen (TAN=NH3-N+NH4-N), total phosphorus (P), and organicmatter characterized by the chemical oxygen demand (COD) and the biological oxygen demand after 5 days (BOD5...

  13. The alkaline tide and ammonia excretion after voluntary feeding in freshwater rainbow trout.

    Science.gov (United States)

    Bucking, Carol; Wood, Chris M

    2008-08-01

    We investigated the potential acid-base and nitrogenous waste excretion challenges created by voluntary feeding in freshwater rainbow trout, with particular focus on the possible occurrence of an alkaline tide (a metabolic alkalosis created by gastric HCl secretion during digestion). Plasma metabolites (glucose, urea and ammonia) were measured at various time points before and after voluntary feeding to satiation (approximately 5% body mass meal of dry commercial pellets), as was the net flux of ammonia and titratable alkalinity to the water from unfed and fed fish. Arterial blood, sampled by indwelling catheter, was examined for post-prandial effects on pH, plasma bicarbonate and plasma CO2 tension. There was no significant change in plasma glucose or urea concentrations following feeding, whereas plasma ammonia transiently increased, peaking at threefold above resting values at 12 h after the meal and remaining elevated for 24 h. The increased plasma ammonia was correlated with an increase in net ammonia excretion to the water, with fed fish significantly elevating their net ammonia excretion two- to threefold between 12 and 48 h post feeding. These parameters did not change in unfed control fish. Fed fish likewise increased the net titratable base flux to the water by approximately threefold, which resulted in a transition from a small net acid flux seen in unfed fish to a large net base flux in fed fish. Over 48 h, this resulted in a net excretion of 13 867 micromol kg(-1) more base to the external water than in unfed fish. The arterial blood exhibited a corresponding rise in pH (between 6 and 12 h) and plasma bicarbonate (between 3 and 12 h) following feeding; however, no respiratory compensation was observed, as PaCO2 remained constant. Overall, there was evidence of numerous challenges created by feeding in a freshwater teleost fish, including the occurrence of an alkaline tide, and its compensation by excretion of base to the external water. The possible

  14. 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

  15. Effects of phenol on ATPase activities in crude gill homogenates of rainbow trout (Salmo gairdneri Richardson)

    Energy Technology Data Exchange (ETDEWEB)

    Poston, T.M.

    1979-01-01

    The ATPase specific activities from crude gill homogenates of rainbow trout were lower than those from microsomal preparations reported in the literature. Sodium pump activity (ouabain sensitive NaK-ATPase) was demonstrable at 37/sup 0/C. An ouabain insensitive NaK-ATPase was demonstrable at temperatures below 30/sup 0/C and may represent a Na-ATPase activity reported by others. Energy of activation at 25/sup 0/C for total NaK-ATPase ws 10,500 cal.mole/sup -1/. Mg-baseline activity had an energy of activation at 25/sup 0/C of 15,600 cal.mole/sup -1/. Mg-baseline activity was thermally labile at temperatures in excess of 30/sup 0/C. Concentrations of Mg/sup +2/ in excess of 5 mM appeared to inhibit total NaK-ATPase activity. At 37/sup 0/C, Na/sup +/ and K/sup +/ exerted little, if any, stimulatory effect on ATPase activities, in spite of the fact that 37/sup 0/C was the only temperature at which sodium pump activity was demonstrable. MS-222 failed to produce any discernible changes in any of the demonstrable ATPase activities in crude gill homogenates. Total NaK-ATPase activities were more sensitive than Mg-baseline activities to in vitro inhibition by phenol. Concentrations of phenol which produce 50% inhibition in total NaK-ATPase produced only 35% inhibition in Mg-baseline activity. The nature of in vitro inhibition was uncompetitive. Sodium pump activity was unaffected by phenol at concentrations as high as 25 mM. An effort was made to demonstrate an in vivo effects of phenol on rainbow trout gill ATPase activites. An infestation of a parasite (Gyrodactilus) on the experimental fish precludes any definative assessment of in vivo effects.

  16. Meta-Analysis of Microarray Data of Rainbow Trout Fry Gonad Differentiation Modulated by Ethynylestradiol.

    Directory of Open Access Journals (Sweden)

    Sophie Depiereux

    Full Text Available Sex differentiation in fish is a highly labile process easily reversed by the use of exogenous hormonal treatment and has led to environmental concerns since low doses of estrogenic molecules can adversely impact fish reproduction. The goal of this study was to identify pathways altered by treatment with ethynylestradiol (EE2 in developing fish and to find new target genes to be tested further for their possible role in male-to-female sex transdifferentiation. To this end, we have successfully adapted a previously developed bioinformatics workflow to a meta-analysis of two datasets studying sex reversal following exposure to EE2 in juvenile rainbow trout. The meta-analysis consisted of retrieving the intersection of the top gene lists generated for both datasets, performed at different levels of stringency. The intersecting gene lists, enriched in true positive differentially expressed genes (DEGs, were subjected to over-representation analysis (ORA which allowed identifying several statistically significant enriched pathways altered by EE2 treatment and several new candidate pathways, such as progesterone-mediated oocyte maturation and PPAR signalling. Moreover, several relevant key genes potentially implicated in the early transdifferentiation process were selected. Altogether, the results show that EE2 has a great effect on gene expression in juvenile rainbow trout. The feminization process seems to result from the altered transcription of genes implicated in normal female gonad differentiation, resulting in expression similar to that observed in normal females (i.e. the repression of key testicular markers cyp17a1, cyp11b, tbx1, as well as from other genes (including transcription factors that respond specifically to the EE2 treatment. The results also showed that the bioinformatics workflow can be applied to different types of microarray platforms and could be generalized to (ecotoxicogenomics studies for environmental risk assessment

  17. 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.

  18. Immunotoxic effects of oil sands-derived naphthenic acids to rainbow trout

    International Nuclear Information System (INIS)

    MacDonald, Gillian Z.; Hogan, Natacha S.; Köllner, Bernd; Thorpe, Karen L.; Phalen, Laura J.; Wagner, Brian D.; Heuvel, Michael R. van den

    2013-01-01

    Naphthenic acids are the major organic constituents in waters impacted by oil sands. To investigate their immunotoxicity, rainbow trout (Oncorhynchus mykiss) were injected with naphthenic acids extracted from aged oil sands tailings water. In two experiments, rainbow trout were injected intraperitoneally with 0, 10, or 100 mg/kg of naphthenic acids, and sampled after 5 or 21 d. Half of the fish from the 21 d exposure were co-exposed to inactivated Aeromonas salmonicida (A.s.) to induce an immune response. A positive control experiment was conducted using an intraperitoneal injection of 100 mg/kg of benzo[a]pyrene, a known immune suppressing compound. T-lymphocytes, B-lymphocytes, thrombocytes, and myeloid cells were counted in blood and lymphatic tissue using flow cytometry. In the 5 d exposure, there was a reduction in blood leucocytes and spleen thrombocytes at the 100 mg/kg dose. However, at 21 d, leucocyte populations showed no effects of exposure with the exception that spleen thrombocyte populations increase at the 100 mg/kg dose. In the 21 d exposure, B- and T-lymphocytes in blood showed a significant Dose × A.s. interaction, indicating stimulated blood cell proliferation due to naphthenic acids alone as well as due to A.s. Naphthenic acid injections did not result in elevated bile fluorescent metabolites or elevated hepatic EROD activity. In contrast to naphthenic acids exposures, as similar dose of benzo[a]pyrene caused a significant decrease in B- and T-lymphocyte absolute counts in blood and relative B-lymphocyte counts in spleen. Results suggest that the naphthenic acids may act via a generally toxic mechanism rather than by specific toxic effects on immune cells.

  19. Adaptation of a Bioinformatics Microarray Analysis Workflow for a Toxicogenomic Study in Rainbow Trout.

    Directory of Open Access Journals (Sweden)

    Sophie Depiereux

    Full Text Available Sex steroids play a key role in triggering sex differentiation in fish, the use of exogenous hormone treatment leading to partial or complete sex reversal. This phenomenon has attracted attention since the discovery that even low environmental doses of exogenous steroids can adversely affect gonad morphology (ovotestis development and induce reproductive failure. Modern genomic-based technologies have enhanced opportunities to find out mechanisms of actions (MOA and identify biomarkers related to the toxic action of a compound. However, high throughput data interpretation relies on statistical analysis, species genomic resources, and bioinformatics tools. The goals of this study are to improve the knowledge of feminisation in fish, by the analysis of molecular responses in the gonads of rainbow trout fry after chronic exposure to several doses (0.01, 0.1, 1 and 10 μg/L of ethynylestradiol (EE2 and to offer target genes as potential biomarkers of ovotestis development. We successfully adapted a bioinformatics microarray analysis workflow elaborated on human data to a toxicogenomic study using rainbow trout, a fish species lacking accurate functional annotation and genomic resources. The workflow allowed to obtain lists of genes supposed to be enriched in true positive differentially expressed genes (DEGs, which were subjected to over-representation analysis methods (ORA. Several pathways and ontologies, mostly related to cell division and metabolism, sexual reproduction and steroid production, were found significantly enriched in our analyses. Moreover, two sets of potential ovotestis biomarkers were selected using several criteria. The first group displayed specific potential biomarkers belonging to pathways/ontologies highlighted in the experiment. Among them, the early ovarian differentiation gene foxl2a was overexpressed. The second group, which was highly sensitive but not specific, included the DEGs presenting the highest fold change and

  20. Immunotoxic effects of oil sands-derived naphthenic acids to rainbow trout

    Energy Technology Data Exchange (ETDEWEB)

    MacDonald, Gillian Z.; Hogan, Natacha S. [Canadian Rivers Institute, Department of Biology, University of Prince Edward Island, 550 University Avenue, Charlottetown, PEI (Canada); Koellner, Bernd [Friedrich Loeffler Institute, Federal Research Institute of Animal Health, Institute of Immunology, Greifswald (Germany); Thorpe, Karen L.; Phalen, Laura J. [Canadian Rivers Institute, Department of Biology, University of Prince Edward Island, 550 University Avenue, Charlottetown, PEI (Canada); Wagner, Brian D. [Department of Chemistry, University of Prince Edward Island, Charlottetown (Canada); Heuvel, Michael R. van den, E-mail: mheuvel@upei.ca [Canadian Rivers Institute, Department of Biology, University of Prince Edward Island, 550 University Avenue, Charlottetown, PEI (Canada)

    2013-01-15

    Naphthenic acids are the major organic constituents in waters impacted by oil sands. To investigate their immunotoxicity, rainbow trout (Oncorhynchus mykiss) were injected with naphthenic acids extracted from aged oil sands tailings water. In two experiments, rainbow trout were injected intraperitoneally with 0, 10, or 100 mg/kg of naphthenic acids, and sampled after 5 or 21 d. Half of the fish from the 21 d exposure were co-exposed to inactivated Aeromonas salmonicida (A.s.) to induce an immune response. A positive control experiment was conducted using an intraperitoneal injection of 100 mg/kg of benzo[a]pyrene, a known immune suppressing compound. T-lymphocytes, B-lymphocytes, thrombocytes, and myeloid cells were counted in blood and lymphatic tissue using flow cytometry. In the 5 d exposure, there was a reduction in blood leucocytes and spleen thrombocytes at the 100 mg/kg dose. However, at 21 d, leucocyte populations showed no effects of exposure with the exception that spleen thrombocyte populations increase at the 100 mg/kg dose. In the 21 d exposure, B- and T-lymphocytes in blood showed a significant Dose Multiplication-Sign A.s. interaction, indicating stimulated blood cell proliferation due to naphthenic acids alone as well as due to A.s. Naphthenic acid injections did not result in elevated bile fluorescent metabolites or elevated hepatic EROD activity. In contrast to naphthenic acids exposures, as similar dose of benzo[a]pyrene caused a significant decrease in B- and T-lymphocyte absolute counts in blood and relative B-lymphocyte counts in spleen. Results suggest that the naphthenic acids may act via a generally toxic mechanism rather than by specific toxic effects on immune cells.

  1. 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.

  2. 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

  3. The physiological stress response and oxidative stress biomarkers in rainbow trout and brook trout from selenium-impacted streams in a coal mining region

    Energy Technology Data Exchange (ETDEWEB)

    Miller, L.L.; Rasmussen, J.B.; Palace, V.P.; Hontela, A. [University of Lethbridge, Lethbridge, AB (Canada). Dept. of Biological Science

    2009-11-15

    Selenium (Se) is an essential element that can be toxic at concentrations slightly greater than those required for homeostasis. The main chronic toxic effects of Se in fish are teratogenic deformities, but Se can also activate the physiological stress response and redox cycle with reduced glutathione causing oxidative damage. Rainbow trout, Oncorhynchus mykiss, appear to be more sensitive to Se than brook trout, Salvelinus fontinalis. The objective of this study was to compare the physiological stress response (plasma cortisol, glucose, triiodothyronine, thyroxine, gill Na+/K+ ATPase, cortisol secretory capacity, K and liver somatic index) and oxidative stress biomarkers (liver GSH, GPx, lipid peroxidation, vitamin A and vitamin E) in rainbow trout (RNTR) and brook trout (BKTR) collected from reference and Se-exposed streams. The physiological stress response was not impaired (cortisol secretory capacity unchanged); although there were species differences in plasma cortisol and plasma glucose levels. Liver GSH, GPx and vitamin levels were higher in RNTR than BKTR, but lipid peroxidation levels were not different. The elevated GSH reserves may make RNTR more sensitive to Se-induced lipid peroxidation, but this may be offset by the RNTR's higher antioxidant (GPx and vitamin) levels. Species-specific biochemical differences may mediate differences in Se sensitivity and be used in aquatic Se risk assessments.

  4. 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

  5. Effects of increased discharge on spawning and age-0 recruitment of rainbow trout in the Colorado River at Lees Ferry, Arizona

    Science.gov (United States)

    Avery, Luke A.; Korman, Josh; Persons, William R.

    2015-01-01

    Negative interactions of Rainbow Trout Oncorhynchus mykiss with endangered Humpback Chub Gila cypha pose challenges to the operation of Glen Canyon Dam (GCD) to manage for both species in the Colorado River. Operations to enhance the Rainbow Trout tailwater fishery may lead to an increase in downstream movement of the trout to areas where they are likely to interact with Humpback Chub. We evaluated the effects of dam operations on age-0 Rainbow Trout in the tailwater fishery to inform managers about how GCD operations could benefit a tailwater fishery for Rainbow Trout; although this could affect a Humpback Chub population farther downstream. A near year-long increase in discharge at GCD in 2011 enabled us to evaluate whether high and stable flows led to increased spawning and production of age-0 Rainbow Trout compared with other years. Rainbow Trout spawning was monitored by fitting a model to observed redd counts to estimate the number of redds created over a spawning season. Data collected during electrofishing trips in July–September and November were used to acquire age-0 trout population and mortality rate estimates. We found that high and stable flows in 2011 resulted in 3,062 redds (1.7 times the mean of all survey years) and a population estimate of 686,000 age-0 Rainbow Trout (second highest on record). Despite high initial abundance, mortality remained low through the year (0.0043%/d) resulting in significant recruitment with a record high November population estimate of 214,000 age-0 Rainbow Trout. Recent monitoring indicates this recruitment event was followed by an increase in downstream migration, which may lead to increased interactions with downstream populations of Humpback Chub. Consequently, while our results indicate that manipulating flow at GCD can be used to manage Rainbow Trout spawning and recruitment, fisheries managers should use flow manipulation in moderation to minimize downstream migration in order to reduce negative

  6. 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...

  7. 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...

  8. 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.

  9. Early feeding of carnivorous rainbow trout (Oncorhynchus mykiss) with a hyperglucidic diet during a short period: effect on dietary glucose utilization in juveniles.

    Science.gov (United States)

    Geurden, I; Aramendi, M; Zambonino-Infante, J; Panserat, S

    2007-06-01

    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 (3 days, stimulus 1) or after yolk absorption (5 days, stimulus 2). Before and after the hyperglucidic stimulus, they received a commercial diet until juvenile stage (>10 g). Fish that did not experience the hyperglucidic stimuli served as controls. The short- and long-term effects of the stimuli were evaluated by measuring the expression of five key genes involved in carbohydrate utilization: alpha-amylase, maltase (digestion), sodium-dependent glucose cotransporter (SGLT1; intestinal glucose transport), and glucokinase and glucose-6-phosphatase, involved in the utilization and production of glucose, respectively. The hyperglucidic diet rapidly increased expressions of maltase, alpha-amylase, and glucokinase in stimulus 1 fish and only of maltase in stimulus 2 fish, probably because of a lower plasticity at this later stage of development. In the final challenge test with juveniles fed a 25% dextrin diet, both digestive enzymes were upregulated in fish that had experienced the hyperglucidic stimulus at first feeding, confirming the possibility of modification of some long-term physiological functions in rainbow trout. In contrast, no persistent molecular adaptations were found for the genes involved in glucose transport or metabolism. In addition, growth and postprandial glycemia were unaffected by the stimuli. In summary, our data show that a short hyperglucidic stimulus during early trout life may permanently influence carbohydrate digestion.

  10. 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.

  11. Pulp and paper mill effluent treatments have differential endocrine-disrupting effects on rainbow trout.

    Science.gov (United States)

    Orrego, Rodrigo; Guchardi, John; Hernandez, Victor; Krause, Rachelle; Roti, Lucia; Armour, Jeffrey; Ganeshakumar, Mathumai; Holdway, Douglas

    2009-01-01

    Endocrine disruption (ED) effects due to pulp and paper mill effluents extracts involving different industrial procedures and effluent treatments (nontreated, primary, and secondary treated) were evaluated using immature triploid rainbow trout in a pulse-exposure toxicity experiment. The protocol involved the use of intraperitoneal injection of mill extracts (solid-phase extraction [SPE]) corrected for individual fish weight and included several laboratory standards (steroidal hormones and phytosterols). Biological endpoints at two different levels of biological organization were analyzed (molecular and individual organism). Results indicated that nonsignificant changes were observed in the individual physiological indices represented by condition factor, liver somatic index, and gonad somatic index during the experiment. Significant induction of liver ethoxyresorufin-O-deethylase activity was observed between different effluent treatments and experimental controls. Significant endocrine-disrupting effects at the reproductive level were observed in all effluent treatments involving significant increments in plasma vitellogenin (VTG) levels. Fish exposed to untreated effluent extracts had significantly higher VTG levels compared to fish exposed to primary and secondary treatment effluent extracts, indicating a decrease of the estrogenic effect due to the effluent treatment. The present study has shown that for the Chilean pulp and paper mill SPE extracts evaluated, an endocrine disruption effect was induced in immature triploid rainbow, reaffirming the significant estrogenic effects demonstrated previously in laboratory and field experiments.

  12. Adhesion to brown trout skin mucus, antagonism against cyst adhesion and pathogenicity to rainbow trout of some inhibitory bacteria against Saprolegnia parasitica .

    Science.gov (United States)

    Carbajal-González, M T; Fregeneda-Grandes, J M; González-Palacios, C; Aller-Gancedo, J M

    2013-04-29

    Biological control of saprolegniosis with bacteria might be an alternative to the use of chemical compounds. Among criteria for the selection of such bacteria are their absence of pathogenicity to fish and their ability to prevent adhesion of the pathogen to the skin mucus. The pathogenicity to rainbow trout of 21 bacterial isolates with in vitro inhibitory activity against Saprolegnia parasitica was studied. Fifteen of the isolates, identified as Aeromonas sobria, Pantoea agglomerans, Pseudomonas fluorescens, Serratia fonticola, Xanthomonas retroflexus and Yersinia kristensenii, were non-pathogenic when injected into rainbow trout. Their capacity to adhere to the skin mucus of male and female brown trout and to reduce the adhesion of S. parasitica cysts under exclusion, competition and displacement conditions was tested. The 15 bacterial isolates showed a low adhesion rate, ranging between 1.7% (for an A. sobria isolate) and 15.3% (a P. fluorescens isolate). This adhesion was greater in the case of mucus from male brown trout than from females. Similarities in the adhesion to male mucus and other substrates and correlation to that observed to polystyrene suggest that adhesion to skin mucus does not depend on the substrate. A high percentage (88.9%) of the S. parasitica cysts adhered to the skin mucus of male brown trout. Almost all of the bacteria reduced this adhesion ratio significantly under exclusion and competition conditions. However, only half of the isolates displaced cysts from skin mucus, and more bacterial cells were necessary for this effect. A novel method to study the adhesion of S. parasitica cysts to skin mucus of trout and their interactions with inhibitory bacteria is described.

  13. 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...

  14. DEVELOPMENT OF A YERSINIA RUCKERI O1 BIOTYPE 2 WATERBORNE CHALLENGE MODEL FOR FUTURE ERM VACCINE TESTING IN RAINBOW TROUT

    DEFF Research Database (Denmark)

    Kragelund Strøm, Helene; Aalbæk, Bent; Otani, Maki

    Yersinia ruckeri (Y.r.) O1 biotype (bt) 2 causes outbreaks of Enteric Redmouth disease (ERM) in vaccinated, farmed rainbow trout around the world. Y.r. O1 bt 1 has been known since first described from the Hagerman Valley in Idaho in the 1950’s and outbreaks have now been controlled by vaccination...... for more than 35 years. Recent years have shown ERM outbreaks caused by Y.r. O1 bt 2 reported from ERM vaccinated farmed rainbow trout stocks in both Europe and the USA. It has been suggested that Y.r. O1 bt 2 is more virulent than bt 1. In order to test this hypothesis we have collected Y.r. O1 isolates...

  15. 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...

  16. 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

  17. 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.

  18. Food resources and trophic relationships of brown, rainbow trout and european grayling in different habitats of Shypit river of the Transcarpathian region

    Directory of Open Access Journals (Sweden)

    S. Kruzhylina

    2016-12-01

    Full Text Available Purpose. To study food resources, feeding conditions and trophic relationships of the brown trout (Salmo trutta morpha fario, rainbow trout (Oncorhynchus mykiss, and European grayling (Thymallus thymallus in a Transcarpatioan river. Methodology. The material on the food resources and feeding of the brown trout, rainbow trout, and European grayling was collected in summer period of 2012 on the Shypit river. The study was performed on two different sites of the river: the first one was located on the middle pre-mountain reach of the river (upstream of the Hydroelectric power plant, the second one – on the mountain reach of the river (near tourist base on typical biotopes: I – with boulders and riffles with fast current; II – with medium size stones and low riffles with moderate current; III – with small stones, sand and slow current. The material was collected and processed according to standard and unified hydrological, ichthyological, and trophological methods. Findings. We studied the level of macrozoobenthos development and obtained data on feeding and trophic relationships among brown trout, rainbow trout, and European grayling on different biotopes on pre-mountain and mountain reaches of the Shypit river. The number of “soft” macrozoobenthos on different biotopes varied from 972 to 2576 ind./m2 with biomasses from 6.3 to 121.8 g/m2. Total diet overlap index (DOI between brown trout and rainbow trout on the biotope with boulders and fast current in the pre-mountain reach was 32.4% by number and 20.3% by biomass, while that on the mountain reach was 49.6% and 52.9%, respectively. On the biotope with medium size stones and moderate current, the diet overlap index between rainbow trout and European grayling in the pre-mountain reach was 19.0% by number and 27.9% by biomass. Originality. First study of the diet and tropic relationships of the brown trout, rainbow trout, and еuropean grayling on different reached of the Shypit river

  19. 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

  20. Assimilation of water and dietary ions by the gastrointestinal tract during digestion in seawater-acclimated rainbow trout

    OpenAIRE

    Bucking, Carol; Fitzpatrick, John L.; Nadella, Sunita R.; McGaw, Iain J.; Wood, Chris M.

    2011-01-01

    Recent studies focusing on the consequences of feeding for ion and water balance in freshwater fish have revealed the need for similar comparative studies in seawater fish. A detailed time course sampling of gastrointestinal (GI) tract contents following the ingestion of a single meal of a commercial diet revealed the assimilation of both water and dietary ions (Na+, Cl-, K+, Ca2+, Mg2+) along the GI tract of seawater-acclimated rainbow trout (Oncorhynchus mykiss) which had been fasted for 1 ...

  1. 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,...

  2. 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.

  3. 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

  4. 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.

  5. Coping with an exogenous glucose overload: glucose kinetics of rainbow trout during graded swimming.

    Science.gov (United States)

    Choi, Kevin; Weber, Jean-Michel

    2016-03-15

    This study examines how chronically hyperglycemic rainbow trout modulate glucose kinetics in response to graded exercise up to critical swimming speed (Ucrit), with or without exogenous glucose supply. Our goals were 1) to quantify the rates of hepatic glucose production (Ra glucose) and disposal (Rd glucose) during graded swimming, 2) to determine how exogenous glucose affects the changes in glucose fluxes caused by exercise, and 3) to establish whether exogenous glucose modifies Ucrit or the cost of transport. Results show that graded swimming causes no change in Ra and Rd glucose at speeds below 2.5 body lengths per second (BL/s), but that glucose fluxes may be stimulated at the highest speeds. Excellent glucoregulation is also achieved at all exercise intensities. When exogenous glucose is supplied during exercise, trout suppress hepatic production from 16.4 ± 1.6 to 4.1 ± 1.7 μmol·kg(-1)·min(-1) and boost glucose disposal to 40.1 ± 13 μmol·kg(-1)·min(-1). These responses limit the effects of exogenous glucose to a 2.5-fold increase in glycemia, whereas fish showing no modulation of fluxes would reach dangerous levels of 114 mM of blood glucose. Exogenous glucose reduces metabolic rate by 16% and, therefore, causes total cost of transport to decrease accordingly. High glucose availability does not improve Ucrit because the fish are unable to take advantage of this extra fuel during maximal exercise and rely on tissue glycogen instead. In conclusion, trout have a remarkable ability to adjust glucose fluxes that allows them to cope with the cumulative stresses of a glucose overload and graded exercise. Copyright © 2016 the American Physiological Society.

  6. Toxicity to rainbow trout of spent still liquors from the distillation of coal

    Energy Technology Data Exchange (ETDEWEB)

    Herbert, D W.M.

    1962-01-01

    From a survey of the literature on the toxicity of ammonium salts, phenol, cyanide, and sulphide to rainbow trout, and from determinations of the toxicity of sodium thiocyanate and sodium thiosulphate, it is postulated that the toxicity of spent still liquors from the distillation of coal should be due mainly to their content of ammonia and monohydric phenols. This is confirmed by experiments showing that the toxicity of an equivalent mixture of ammonium chloride and phenol is nearly as great as that of a spent liquor from a gas works, and that phenol is almost as toxic as mixtures of the monohydric phenols known to be present in such liquors. Experiments on the effect of pH value, hardness, dissolved-oxygen concentration and temperature on the threshold concentration of monohydric phenols are described and compared with similar data for ammonia. Experiments with ammonia and phenols suggest that a mixture of these substances is at its threshold concentration when AS/AT/+PS/PT=I,AS and PS being the concentrations of un-ionized ammonia and monohydric phenols in solution and AT and PT being the threshold concentrations of these substances when tested individually in the same dilution water. A method based on these experiments for predicting the toxicity of ammonia-phenol mixtures from the chemical composition of their solutions is described, and evaluated against laboratory determinations of the toxicity of spent liquors from a coke oven, and against the death or survival of trout held captive in a stream polluted with spent liquor from a gas works. It is concluded that the correspondence between the predicted and observed toxicities is good enough for the method to be used as a basis for assessing whether trout could live in a stream to which a particular spent still liquor was discharged, or when deciding what treatment the effluent should receive to make it safe for such fish after discharge.

  7. 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

  8. Differential conservation and divergence of fertility genes boule and dazl in the rainbow trout.

    Directory of Open Access Journals (Sweden)

    Mingyou Li

    Full Text Available BACKGROUND: The genes boule and dazl are members of the DAZ (Deleted in Azoospermia family encoding RNA binding proteins essential for germ cell development. Although dazl exhibits bisexual expression in mitotic and meiotic germ cells in diverse animals, boule shows unisexual meiotic expression in invertebrates and mammals but a bisexual mitotic and meiotic expression in medaka. How boule and dazl have evolved different expression patterns in diverse organisms has remained unknown. METHODOLOGY AND PRINCIPAL FINDINGS: Here we chose the fish rainbow trout (Oncorhynchus mykiss as a second lower vertebrate model to investigate the expression of boule and dazl. By molecular cloning and sequence comparison, we identified cDNAs encoding the trout Boule and Dazl proteins, which have a conserved RNA-recognition motif and a maximal similarity to their homologs. By RT-PCR analysis, adult RNA expression of trout boule and dazl is restricted to the gonads of both sexes. By chromogenic and two-color fluorescence in situ hybridization, we revealed bisexual and germline-specific expression of boule and dazl. We found that dazl displays conserved expression throughout gametogenesis and concentrates in the Balbinani's body of early oocytes and the chromatoid body of sperm. Surprisingly, boule exhibits mitotic and meiotic expression in the male but meiosis-specific expression in the female. CONCLUSIONS: Our data underscores differential conservation and divergence of DAZ family genes during vertebrate evolution. We propose a model in which the diversity of boule expression in sex and stage specificity might have resulted from selective loss or gain of its expression in one sex and mitotic germ cells.

  9. 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

  10. 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

  11. 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.

  12. 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

  13. 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®.

  14. 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.

  15. 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.

  16. 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

  17. 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.

  18. 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.

  19. Native and exotic fishes in a Patagonian reservoir with rainbow trout cage culture: spatial and trophic resource use

    Directory of Open Access Journals (Sweden)

    Nabaes Jodar Diego N.

    2017-01-01

    Full Text Available Although the interactions of exotic salmonids with native Patagonian fishes are well known, little is known about the ecology and impact of farmed fish escapees. Salmonid production in Argentina is largely concentrated in the Alicurá reservoir in north Patagonia, where fish community studies have been scarce. Here, we assess and compare the spatial distribution, body size–condition and diet of the different fish species in this reservoir. Strong vertical segregation was observed between exotic rainbow trout Oncorhynchus mykiss (both escapees and wild, dominating the littoral zone, and native Percichthys trucha which dominate the medium and deep strata. Low piscivory–benthivory and high zooplanktivory were observed for rainbow trout, both traits being uncommon at a regional scale. Escaped farmed rainbow trout (ERT diet included abundant indigestible items along with wild prey. Higher body condition of P. trucha close to farms, as well as the regionally unprecedented high incidence of Daphnia sp. in the guts of all the species suggest that farm nutrient discharges have had significant impacts. Finally, the high body condition of ERT, together with their wild food diet and the long dispersal distance observed, demonstrate post-escape success, drawing our attention to potential upstream dispersion affecting the biodiversity and fisheries of Patagonian rivers and lakes.

  20. 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

  1. 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....

  2. [Digestive utilization of purified cellulose in the rainbow trout (Salmo gairdneri) and the common carp (Cyprinus carpio)].

    Science.gov (United States)

    Bergot, F

    1981-01-01

    A semi-purified diet containing 22 p. 100 of a wood cellulose extract without lignin but still containing 22 p. 100 of hemicelluloses was distributed for one month to rainbow trout and common carp reared at 17 and 20 degrees C, respectively. The digestibility of the main dietary constituents was determined by an indirect method using chrome oxide as an inert tracer. The feces were recovered by a continuous automatic collector which rapidly removed them from the water, minimizing alteration by leaching. The cellulose content was estimated by the Weende (crude fiber) and the Van Soest (neutral detergent fiber and acid detergent fiber) methods. The digestibility coefficients obtained for trout as well as for carp indicate that cellulose and hemicelluloses were not digested. In both species, volatile fatty acid concentration in the different segments of the digestive tract was low (less than 10 mM/l). These results lead us to suggest that trout and carp cannot degrade purified cellulose.

  3. 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...

  4. Bisphenol A accumulation in eggs disrupts the endocrine regulation of growth in rainbow trout larvae

    Energy Technology Data Exchange (ETDEWEB)

    Birceanu, Oana; Servos, Mark R.; Vijayan, Mathilakath M., E-mail: matt.vijayan@ucalgary.ca

    2015-04-15

    Highlights: • BPA in eggs reduces growth and increases food conversion ratio in trout larvae. • BPA in eggs disrupts larval transcript abundance of genes involved in GH/IGF axis. • BPA in eggs disrupts thyroid hormone receptor mRNA levels. • BPA in eggs consistently suppressed IGF-1rb mRNA levels during early development. - Abstract: Bisphenol A (BPA), a monomer used in the production of plastics and epoxy resins, is ubiquitously present in the aquatic environment. BPA is considered a weak estrogen in fish, but the effects of this chemical on early developmental events are far from clear. We tested the hypothesis that BPA accumulation in eggs, mimicking maternal transfer, disrupts growth hormone/insulin-like growth factor (GH/IGF) axis function, leading to defects in larval growth in rainbow trout. Trout oocytes were exposed to 0 (control), 0.3, 3, and 30 μg ml{sup −1} BPA for 3 h, which led to an accumulation of around 0, 1, 4 and 40 ng BPA per egg, respectively. All treatment groups were fertilized with clean milt and reared in clean water for the rest of the experiment. The embryo BPA content declined over time in all groups and was completely eliminated by 42 days post-fertilization (dpf). Hatchlings from BPA accumulated eggs had higher water content and reduced total energy levels prior to first feed. There was an overall reduction in the specific growth rate and food conversion ratio in larvae reared from BPA-laden eggs. BPA accumulation disrupted the mRNA abundance of genes involved in GH/IGF axis function, including GH isoforms and their receptors, IGF-1 and -2 and IGF receptors, in a life stage-dependent manner. Also, there was a temporal disruption in the mRNA levels of thyroid hormone receptors in the larvae raised from BPA-laden eggs. Altogether, BPA accumulation in eggs, mimicking maternal transfer, affects larval growth and the mode of action involves disruption of genes involved in the GH/IGF and thyroid axes function in trout.

  5. Bisphenol A accumulation in eggs disrupts the endocrine regulation of growth in rainbow trout larvae

    International Nuclear Information System (INIS)

    Birceanu, Oana; Servos, Mark R.; Vijayan, Mathilakath M.

    2015-01-01

    Highlights: • BPA in eggs reduces growth and increases food conversion ratio in trout larvae. • BPA in eggs disrupts larval transcript abundance of genes involved in GH/IGF axis. • BPA in eggs disrupts thyroid hormone receptor mRNA levels. • BPA in eggs consistently suppressed IGF-1rb mRNA levels during early development. - Abstract: Bisphenol A (BPA), a monomer used in the production of plastics and epoxy resins, is ubiquitously present in the aquatic environment. BPA is considered a weak estrogen in fish, but the effects of this chemical on early developmental events are far from clear. We tested the hypothesis that BPA accumulation in eggs, mimicking maternal transfer, disrupts growth hormone/insulin-like growth factor (GH/IGF) axis function, leading to defects in larval growth in rainbow trout. Trout oocytes were exposed to 0 (control), 0.3, 3, and 30 μg ml −1 BPA for 3 h, which led to an accumulation of around 0, 1, 4 and 40 ng BPA per egg, respectively. All treatment groups were fertilized with clean milt and reared in clean water for the rest of the experiment. The embryo BPA content declined over time in all groups and was completely eliminated by 42 days post-fertilization (dpf). Hatchlings from BPA accumulated eggs had higher water content and reduced total energy levels prior to first feed. There was an overall reduction in the specific growth rate and food conversion ratio in larvae reared from BPA-laden eggs. BPA accumulation disrupted the mRNA abundance of genes involved in GH/IGF axis function, including GH isoforms and their receptors, IGF-1 and -2 and IGF receptors, in a life stage-dependent manner. Also, there was a temporal disruption in the mRNA levels of thyroid hormone receptors in the larvae raised from BPA-laden eggs. Altogether, BPA accumulation in eggs, mimicking maternal transfer, affects larval growth and the mode of action involves disruption of genes involved in the GH/IGF and thyroid axes function in trout

  6. 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...

  7. 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.

  8. 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

  9. 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.

  10. Using accelerated life testing procedures to compare the relative sensitivity of rainbow trout and the federally listed threatened bull trout to three commonly used rangeland herbicides (picloram, 2,4-D, and clopyralid).

    Science.gov (United States)

    Fairchild, James F; Allert, Ann; Sappington, Linda S; Nelson, Karen J; Valle, Janet

    2008-03-01

    We conducted 96-h static acute toxicity studies to evaluate the relative sensitivity of juveniles of the threatened bull trout (Salvelinus confluentus) and the standard cold-water surrogate rainbow trout (Onchorhyncus mykiss) to three rangeland herbicides commonly used for controlling invasive weeds in the northwestern United States. Relative species sensitivity was compared using three procedures: standard acute toxicity testing, fractional estimates of lethal concentrations, and accelerated life testing chronic estimation procedures. The acutely lethal concentrations (ALC) resulting in 50% mortality at 96 h (96-h ALC50s) were determined using linear regression and indicated that the three herbicides were toxic in the order of picloram acid > 2,4-D acid > clopyralid acid. The 96-h ALC50 values for rainbow trout were as follows: picloram, 41 mg/L; 2.4-D, 707 mg/L; and clopyralid, 700 mg/L. The 96-h ALC50 values for bull trout were as follows: picloram, 24 mg/L; 2.4-D, 398 mg/L; and clopyralid, 802 mg/L. Fractional estimates of safe concentrations, based on 5% of the 96-h ALC50, were conservative (overestimated toxicity) of regression-derived 96-h ALC5 values by an order of magnitude. Accelerated life testing procedures were used to estimate chronic lethal concentrations (CLC) resulting in 1% mortality at 30 d (30-d CLC1) for the three herbicides: picloram (1 mg/L rainbow trout, 5 mg/L bull trout), 2,4-D (56 mg/L rainbow trout, 84 mg/L bull trout), and clopyralid (477 mg/L rainbow trout; 552 mg/L bull trout). Collectively, the results indicated that the standard surrogate rainbow trout is similar in sensitivity to bull trout. Accelerated life testing procedures provided cost-effective, statistically defensible methods for estimating safe chronic concentrations (30-d CLC1s) of herbicides from acute toxicity data because they use statistical models based on the entire mortality:concentration:time data matrix.

  11. 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

  12. 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