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Sample records for catfish trout tilapia

  1. Determination of cyanuric acid residues in catfish, trout, tilapia, salmon and shrimp by liquid chromatography-tandem mass spectrometry

    International Nuclear Information System (INIS)

    In May 2007, investigators discovered that waste material from the pet food manufacturing process contaminated with melamine (MEL) and/or cyanuric acid (CYA) had been added to hog and chicken feeds. At this time, investigators also learned that adulterated wheat gluten had been used in the manufacture of aquaculture feeds. Concern that the contaminated feed had been used in aquaculture and could enter the human food supply prompted the development of a method for the determination of CYA residues in the edible tissues of fish and shrimp. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) was employed as a sensitive technique for the analysis of CYA in catfish, tilapia, salmon, trout and shrimp tissue. CYA was extracted from ground fish or shrimp with an acetic acid solution, defatted with hexane, and isolated with a graphitic carbon black solid-phase extraction column. Residues were separated from matrix components using a porous graphitic carbon LC column, and then analyzed with electrospray ionization in negative ion mode on a triple quadrupole mass spectrometer. Selective reaction monitoring was performed on the [M-H]-m/z 128 ion resulting in the product ions m/z 85 and 42. Recoveries from catfish, tilapia and trout fortified with 10-100 μg kg-1 of CYA averaged 67% with a relative standard deviation (R.S.D.) of 18% (n = 107). The average method detection limit (MDL) for catfish, tilapia and trout is 3.5 μg kg-1. An internal standard, 13C3-labeled CYA, was used in the salmon and shrimp extractions. Average recovery of CYA from salmon was 91% (R.S.D. = 15%, n = 18) with an MDL of 7.4 μg kg-1. Average recovery of CYA from shrimp was 85% (R.S.D. = 10%, n = 13) with an MDL of 3.5 μg kg-1

  2. Determination of cyanuric acid residues in catfish, trout, tilapia, salmon and shrimp by liquid chromatography-tandem mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Karbiwnyk, Christine M. [Animal Drugs Research Center, U.S. Food and Drug Administration, P.O. Box 25087, Denver, CO 80225-0087 (United States)], E-mail: christine.karbiwnyk@fda.hhs.gov; Andersen, Wendy C.; Turnipseed, Sherri B. [Animal Drugs Research Center, U.S. Food and Drug Administration, P.O. Box 25087, Denver, CO 80225-0087 (United States); Storey, Joseph M.; Madson, Mark R. [Denver District Laboratory, U.S. Food and Drug Administration, P.O. Box 25087, Denver, CO 80225-0087 (United States); Miller, Keith E. [Center for Veterinary Medicine, U.S. Food and Drug Administration, 8401 Muirkirk Road, Laurel, MD 20708 (United States); Gieseker, Charles M.; Miller, Ron A.; Rummel, Nathan G.; Reimschuessel, Renate [University of Denver, Department of Chemistry and Biochemistry, Denver, CO 80208 (United States)

    2009-04-01

    In May 2007, investigators discovered that waste material from the pet food manufacturing process contaminated with melamine (MEL) and/or cyanuric acid (CYA) had been added to hog and chicken feeds. At this time, investigators also learned that adulterated wheat gluten had been used in the manufacture of aquaculture feeds. Concern that the contaminated feed had been used in aquaculture and could enter the human food supply prompted the development of a method for the determination of CYA residues in the edible tissues of fish and shrimp. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) was employed as a sensitive technique for the analysis of CYA in catfish, tilapia, salmon, trout and shrimp tissue. CYA was extracted from ground fish or shrimp with an acetic acid solution, defatted with hexane, and isolated with a graphitic carbon black solid-phase extraction column. Residues were separated from matrix components using a porous graphitic carbon LC column, and then analyzed with electrospray ionization in negative ion mode on a triple quadrupole mass spectrometer. Selective reaction monitoring was performed on the [M-H]{sup -}m/z 128 ion resulting in the product ions m/z 85 and 42. Recoveries from catfish, tilapia and trout fortified with 10-100 {mu}g kg{sup -1} of CYA averaged 67% with a relative standard deviation (R.S.D.) of 18% (n = 107). The average method detection limit (MDL) for catfish, tilapia and trout is 3.5 {mu}g kg{sup -1}. An internal standard, {sup 13}C{sub 3}-labeled CYA, was used in the salmon and shrimp extractions. Average recovery of CYA from salmon was 91% (R.S.D. = 15%, n = 18) with an MDL of 7.4 {mu}g kg{sup -1}. Average recovery of CYA from shrimp was 85% (R.S.D. = 10%, n = 13) with an MDL of 3.5 {mu}g kg{sup -1}.

  3. Halogenated contaminants in farmed salmon, trout, tilapia, pangasius, and shrimp.

    Science.gov (United States)

    van Leeuwen, S P J; van Velzen, M J M; Swart, C P; van der Veen, I; Traag, W A; de Boer, J

    2009-06-01

    Polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins and dibenzo-p-furans (PCDD/Fs), organochlorine pesticides (OCPs), polybrominated diphenyl ethers (PBDEs), hexabromocyclododecane diastereomers (HBCDs), and perfluorinated compounds (PFCs) were analyzed in popular farmed fish such as salmon, trout, tilapia, and pangasius and in farmed shrimp. The samples originated from southeast Asia, Europe, and South America. Results show the following: (i) Carnivorous species contained higher contaminant concentrations than omnivorous species. (ii) Contaminant concentrations generally decreased per species in the following order of salmon > trout > tilapia approximately equal to pangasius approximately equal to shrimp. (iii) Most contaminant concentrations decreased in the following order of PCBs approximately equal to dichloro-diphenyl-trichloroethanes (DDTs) > hexachlorobenzene approximately equal to pentachlorobenzene approximately equal to dieldrin approximately equal to PBDEs approximately equal to alpha-HBCD approximately equal to perfluorooctane sulfonate (PFOS) > World Health Organization toxic equivalents (WHO-TEQ) [PCDD/Fs and dioxin-like (dl)-PCBs]. (iv) Contaminant concentrations were very low (mostly <1 ng/g wet weight) and far below the European and Dutch legislative limits. (v) Contaminant concentrations in farmed shrimp, pangasius, and tilapia were lower than those in wild fish, whereas contaminant concentrations in farmed salmon and trout were higher than those in lean wild marine fish. From the five species investigated, salmon is predominantly responsible (97%) for human exposure to the sum of the investigated contaminants. The contribution of trout, tilapia, pangasius, and shrimp is small (3%) because contaminant concentrations and consumption volumes were much lower. PMID:19569323

  4. Multi pesticide and PCB residues in Nile tilapia and catfish in Assiut city, Egypt.

    Science.gov (United States)

    Yahia, Doha; Elsharkawy, Eman E

    2014-01-01

    The current study investigated the levels of multi pesticide residues in the highly consumed types of Nile fish in Egypt: tilapia and cat fish. A total of 50 Nile tilapia (Oreochromis niloticus) and 50 African catfish (Clarias gariepinus) were collected from two areas in Assiut city, where most industries are situated and where agricultural activities and raising of farm animals are the main activities. In the first area, Elwasta, there is an electrical power station, and the second area, Mankbad, there is a cement factory. Fish samples were analyzed by High Resolution Gas Chromatography/Mass Spectrometry. Average pesticide residue concentrations±SE in muscle of tilapia and catfish (n = 10 pooled samples with five fish each) were determined. The results indicated the presence of different types of organophosphorous (OPs), organochlorine (OC), polychlorinated biphenyles (PCBs), hexachlorobenzene (HCB) and trifluralin pesticides in Elwasta and Mankbad in varying degrees. Diazenon was the only OP pesticide which exceeded the permissible limit in both investigated areas with the two types of fish. On the other hand, OCs, PCBs, HCB and trifluralin pesticide residue levels have not exceeded the maximum allowable concentration limit. In general, a higher pesticide residue level was obtained in Mankbad than Elwasta. In addition, higher values are realized for the detected pesticide residues in cat fish than tilapia. The results of the study have shown the extensive and recent use of these types of pesticides in the present time in Egypt. PMID:23911921

  5. Successful xenogeneic germ cell transplantation from Jundia catfish (Rhamdia quelen) into adult Nile tilapia (Oreochromis niloticus) testes.

    Science.gov (United States)

    Silva, M A; Costa, G M J; Lacerda, S M S N; Brandão-Dias, P F P; Kalapothakis, E; Silva Júnior, A F; Alvarenga, E R; França, L R

    2016-05-01

    Fish germ cell transplantation presents several important potential applications for aquaculture, including the preservation of germplasm from endangered fish species with high genetic and commercial values. Using this technique in studies developed in our laboratory with adult male Nile tilapias (Oreochromis niloticus), all the necessary procedures were successfully established, allowing the production of functional sperm and healthy progeny approximately 2months after allogeneic transplantation. In the present study, we evaluated the viability of the adult Nile tilapia testis to generate sperm after xenogeneic transplant of germ cells from sexually mature Jundia catfish (Rhamdia quelen) that belong to a different taxonomic order. Therefore, in order to investigate at different time-periods post-transplantation, the presence and development of donor PKH26 labeled catfish germ cells were followed in the tilapia seminiferous tubules. From 7 to 20days post-transplantation, only PKH26 labeled spermatogonia were observed, whereas spermatocytes at different stages of development were found at 70days. Germ cell transplantation success and progression of spermatogenesis were indicated by the presence of labeled PKH26 spermatids and sperm on days 90 and 120 post-transplantation, respectively. Confirming the presence of the catfish genetic material in the tilapia testis, all recipient tilapias evaluated (n=8) showed the genetic markers evaluated. Therefore, we demonstrated for the first time that the adult Nile tilapia testis offers the functional conditions for development of spermatogenesis with sperm production from a fish species belonging to a different order, which provides an important new venue for aquaculture advancement. PMID:26972155

  6. Genetic Relatedness of Salmonella Serovars Isolated from Catfish (Clarias gariepinus) and Tilapia (Tilapia mossambica) Obtained from Wet Markets and Ponds in Penang, Malaysia.

    Science.gov (United States)

    Budiati, Titik; Rusul, Gulam; Wan-Abdullah, Wan Nadiah; Chuah, Li-Oon; Ahmad, Rosma; Thong, Kwai Lin

    2016-04-01

    A total of 43 Salmonella enterica isolates belonging to different serovars (Salmonella Albany, Salmonella Agona, Salmonella Corvallis, Salmonella Stanley, Salmonella Typhimurium, Salmonella Mikawasima, and Salmonella Bovismorbificans) were isolated from catfish (Clarias gariepinus) and tilapia (Tilapia mossambica) obtained from nine wet markets and eight ponds in Penang, Malaysia. Thirteen, 19, and 11 isolates were isolated from 9 of 32 catfish, 14 of 32 tilapia, and 11 of 44 water samples, respectively. Fish reared in ponds were fed chicken offal, spoiled eggs, and commercial fish feed. The genetic relatedness of these Salmonella isolates was determined by random amplified polymorphic DNA PCR (RAPD-PCR) using primer OPC2, repetitive extragenic palindromic PCR (REP-PCR), and pulsed-field gel electrophoresis (PFGE). Composite analysis of the RAPD-PCR, REP-PCR, and PFGE results showed that the Salmonella serovars could be differentiated into six clusters and 15 singletons. RAPD-PCR differentiated the Salmonella isolates into 11 clusters and 10 singletons, while REP-PCR differentiated them into 4 clusters and 1 singleton. PFGE differentiated the Salmonella isolates into seven clusters and seven singletons. The close genetic relationship of Salmonella isolates from catfish or tilapia obtained from different ponds, irrespective of the type of feed given, may be caused by several factors, such as the quality of the water, density of fish, and size of ponds. PMID:27052872

  7. Edwardsiella tarda and Aeromonas hydrophila isolated from diseased Southern flounder (Paralichthys lethostigma) are virulent to channel catfish and Nile tilapia

    Science.gov (United States)

    The aim of this study is to identify bacterial pathogens isolated from diseased Southern flounder and determine their virulence to channel catfish and Nile tilapia. Twenty five Gram-negative bacteria isolates were recovered from five tissues (skin lesions, brain, liver, intestine, and posterior kidn...

  8. Edwardsiella tarda and Aeromonas hydrophila isolated from diseased Southern flounder (Paralichthys lethostigma) are virulent to channel catfish and Nile tilapia

    Institute of Scientific and Technical Information of China (English)

    Julia W Pridgeon; Phillip H Klesius; Gregory A Lewbart; Harry V Daniels; Megan Jacob

    2014-01-01

    Objective:To identify bacteria isolated from diseased Southern flounder and determine whether they are virulent to channel catfish and Nile tilapia. Methods:Gram-negative bacteria isolates were recovered from five tissues of diseased Southern flounder (Paralichthys lethostigma). The isolates were subjected to biochemical and molecular identification followed by virulence study in fish. Results: Based on biochemical analysis, the 25 isolates were found to share homologies with either Edwardsiella tarda (E. tarda) or Aeromonas hydrophila (A. hydrophila). Based on sequencing results of partial 16S rRNA gene, 15 isolates shared 100%identities with the 16S rRNA sequence of previously identified E. tarda strain TX1, whereas the other 10 isolates shared 100%identities with the 16S rRNA sequence of previously identified A. hydrophila strain An4. When healthy fish were exposed to flounder isolate by intracoelomic injection, the LD50 values of flounder isolate E. tarda to channel catfish or Nile tilapia [(10±2) g] were 6.1í104 and 1.1í107 CFU/fish, respectively, whereas that of flounder isolate A. hydrophila to channel catfish and Nile tilapia were 1.4í107 and 5.6í107 CFU/fish, respectively. Conclusions: This is the first report that E. tarda and A. hydrophila isolated from diseased Southern flounder are virulent to catfish and tilapia.

  9. Effect of darting phenomenon of African catfish Heterobranchus longifilis (Burchell 1822) on growth performance of Nile tilapia: Oreochromis niloticus (Linnaeus, 1758)

    OpenAIRE

    Ofem, B.; Ikpi, G.; Ayotunde, A.

    2005-01-01

    Replicate Ponds of 0.02ha stocked at 500 catfishes with 20,000 tilapia/ha were used to assess growth performance of O.niloticus, average weight 50.4g with (i) darted catfish; H.longifilis (shooters) average weight 60.3g (ii) non-shooters of H.longifilis, average weight 35.4g. Final mean weight, mean growth rate, specific growth rate and food conversion ratio were 499.5g 26g/day, 1.36% and 5.58% respectively for O.niloticus stocked with longifilis (shooters) and 440.4g 2.3g/day 1.23% and 5.58%...

  10. Determining the safety and suitability of fluorescein dye for characterization of skin ulcerations in cultured Nile tilapia (Oreochromis niloticus and African sharptooth catfish (Clarias gariepinus

    Directory of Open Access Journals (Sweden)

    Mai D. Ibrahem

    2010-10-01

    Full Text Available There is a need to identify the presence of lesions in fish skin as soon as they erupt. Fish skin lesions are either macroscopic (can be visualized by the naked eye or microscopic (difficult to detect with the naked eye. Skin wounds resulting in loss of the epithelium (superficial or deep ulcers are serious as they may interfere with osmoregulation and open portals for opportunistic pathogens. Herein, we report on the use of a fluorescein dye for the detection of skin ulcers that cannot be seen by the naked eye. Due to their importance in aquaculture endeavors in Egypt, this study focused on two indigenous species, the Nile tilapia (Oreochromis niloticus and the scale-less African sharptooth catfish (Clarias gariepinus. Fluorescein dye was tested for safety to fish without interfering with microbiological analysis. Parallel to the use of the flourescein dye, the detected ulcers were examined for the presence of bacteria or tissue alterations. Further, we experimentally induced the formation of skin ulcers in O. niloticus physically or by injecting Aeromons hydrophila, and then assessed the utility of fluorescein dye in detecting the induced skin lesions. Results obtained in this study demonstrated that fluorescein dye application is harmless to Nile tilapia at concentrations up to 0.5 mg fluorescein/ml water for up to 15 min. Indeed, a low dose of fluorescein (0.10 mg/ml for 5 min could identify very minute skin abrasions. We highly recommend the use of fluorescein dye for the evaluation of skin health in farmed fish species and the visualization of minute skin abrasions.

  11. Development and efficacy of novobiocin and rifampicin-resistant Aeromonas hydrophila as novel vaccines in channel catfish and Nile tilapia

    Science.gov (United States)

    Three attenuated Aeromonas hydrophila vaccines were developed from the virulent 2009 West Alabama isolates through selection for resistance to both novobiocin and rifampicin. When channel catfish (Ictalurus punctatus) were IP injected with 4×105 colony-forming units (CFU) of the mutants, no fish die...

  12. Using the Monte Carlo method for the economic evaluation of polycultures of silver catfish, carps and tilapia-the-nile as an alternative model of fish farming for small properties

    Directory of Open Access Journals (Sweden)

    Filipe Ritter

    2014-11-01

    Full Text Available With a growing world population and increasing demand for quality food in sufficient quantities, the aquaculture fits in this context as a producer of high quality animal protein with high productivity. The fish production in ponds has practiced for over five decades in Rio Grande do Sul state. The fish culture system commonly used is the carp only polyculture, which consists in culturing different carp species aiming to improve the performance of each one and, therefore, achieve high productivity. The carp polyculture has a low technological level and the production obtained is considered small moreover, the release of effluents in natural water bodies may cause an imbalance in the natural aquatic environment. Some studies have been performed adding the silver catfish to the traditional polyculture. Also, several studies were performed about economic viability, but with a single species, or consortium, as is the case of polyculture of shrimp and Nile tilapia. We tested the polyculture with partial substitution of 25, 50 and 75% of carps by silver catfish and Nile tilapia. We analyzed the economic viability of all substitution rates by obtaining the Net Present Value (NPV, Annual Value (AV, Internal Rate of Return (IRR and Pay Back period. In conditions of uncertainty, we held on sensitivity analysis and evaluation through the Monte Carlo method. We concluded that substitution rate of 25% of carps by silver catfish and Nile tilapia has higher biomass production and better effluent quality. Regarding economic analysis, an investment in polyculture with vita useful 25 years is economically feasible for a fee Minimum Attractiveness (TMA of 6.17%.

  13. Expansion of the Scope of AOAC First Action Method 2012.25--Single-Laboratory Validation of Triphenylmethane Dye and Leuco Metabolite Analysis in Shrimp, Tilapia, Catfish, and Salmon by LC-MS/MS.

    Science.gov (United States)

    Andersen, Wendy C; Casey, Christine R; Schneider, Marilyn J; Turnipseed, Sherri B

    2015-01-01

    Prior to conducting a collaborative study of AOAC First Action 2012.25 LC-MS/MS analytical method for the determination of residues of three triphenylmethane dyes (malachite green, crystal violet, and brilliant green) and their metabolites (leucomalachite green and leucocrystal violet) in seafood, a single-laboratory validation of method 2012.25 was performed to expand the scope of the method to other seafood matrixes including salmon, catfish, tilapia, and shrimp. The validation included the analysis of fortified and incurred residues over multiple weeks to assess analyte stability in matrix at -80°C, a comparison of calibration methods over the range 0.25 to 4 μg/kg, study of matrix effects for analyte quantification, and qualitative identification of targeted analytes. Method accuracy ranged from 88 to 112% with 13% RSD or less for samples fortified at 0.5, 1.0, and 2.0 μg/kg. Analyte identification and determination limits were determined by procedures recommended both by the U. S. Food and Drug Administration and the European Commission. Method detection limits and decision limits ranged from 0.05 to 0.24 μg/kg and 0.08 to 0.54 μg/kg, respectively. AOAC First Action Method 2012.25 with an extracted matrix calibration curve and internal standard correction is suitable for the determination of triphenylmethane dyes and leuco metabolites in salmon, catfish, tilapia, and shrimp by LC-MS/MS at a residue determination level of 0.5 μg/kg or below. PMID:26024871

  14. Bath immersion, booster vaccination strategy holds potential for protecting juvenile tilapia against Streptococcus iniae

    Science.gov (United States)

    Streptococcus iniae is a significant bacterial pathogen that causes hemorrhagic septicemia and meningoencephalitis in tilapia, hybrid striped bass, rainbow trout, olive flounder, yellowtail, barramundi and other species of cultured and wild fish worldwide. In tilapia production, vaccination of fry ...

  15. Growth of monosex hybrid tilapia in the labortory and sewage oxidation ponds

    International Nuclear Information System (INIS)

    Studies were conducted to evaluate the potential of monosex hybrid tilapia (female T. mossambica x male T. hornorum) in waste-heat polyculture systems. The optimum growth temperature for this hybrid was found to be 320C in laboratory experiments. Experiments in sewage pond cage culture in the temperature range of 23 to 330C at stocking densities of approximately 53 fish/m3 were also conducted. At fish sizes between 5 and 12 cm TL, estimated annual production is approximately 50,000 kg/ha/yr (50,000 lb/acre/yr). Fish in the sewage oxidation ponds grew significantly faster than fish fed trout chow at optimum temperature in the laboratory, even though temperatures in the sewage ponds averaged below the optimum growth temperature. Techniques to accelerate growth rates are being explored. Exposure to gamma radiation (500 rads), known to cause significant increases in channel catfish growth rate, was found to have a similar effect on tilapia. After a 20-week growth period, exposed fish weighed an average of 20% more than controls

  16. Evaluation of an in vitro cell assay to select attenuated bacterial mutants of Aeromonas hydrophila and Edwardsiella tarda to channel catfish

    Science.gov (United States)

    Both Aeromonas hydrophila (causative agent of motile aeromonas septicemia) and Edwardsiella tarda (causative agent of enteric septicemia) are Gram-negative bacteria widely distributed in aquatic environments, affecting many fish species worldwide, including channel catfish and tilapia. To control ba...

  17. Growth and production of the African catfish, Clarias lazera (C. & V.): I. Effects of stocking density, pond size and mixed culture with tilapia (Sarotherodon niloticus L.) under extensive field conditions

    NARCIS (Netherlands)

    Hogendoorn, H.; Koops, W.J.

    1981-01-01

    Growth and production of C. lazera (C. & V.) and S. niloticus L. in mono-and mixed culture were studied in relation to stocking density and pond size using a low grade feed. The biomass after 24 weeks ranged from 16 to 115 g·m−2 for tilapia and from 50 to 266 g·m−2 for C. lazera. Independent of the

  18. Bacterial distribution and tissue targets following experimental Edwardsiella ictaluri infection in nile tilapia Oreochromis niloticus

    Science.gov (United States)

    Edwardsiella ictaluri, a Gram-negative enteric bacterium, is the known etiological agent of enteric septicemia of catfish. In the last few years, different strains have been implicated as the causative agent of mortality events in cultured fish, including Nile tilapia Oreochromis niloticus L. Due to...

  19. Induction of lauric acid omega-hydroxylation by peroxisomal proliferators in bluegill and catfish

    Energy Technology Data Exchange (ETDEWEB)

    Haasch, M.L. [Univ. of Maryland, Solomons, MD (United States); Henderson, M.C.; Buhler, D.R. [Oregon State Univ. Corvallis, OR (United States)

    1995-12-31

    Peroxisome proliferating agents (PPAs) are a structurally diverse group of chemicals that include environmental chemical contaminants such as certain chlorinated herbicides, solvents and plasticizers. PPAs have previously been shown to induce anti-trout laruci acid hydroxylase immunoreactive proteins in bluegill and catfish. In this investigation, induction of lauric acid hydroxylase activity and immunoreactive proteins was confirmed, and the mass spectral analysis of specific hydroxylation products was performed in order to identify possible species-specific differences in fatty acid metabolism. Male bluegill (Lepomis macrochirus) and channel catfish (Ictalurus punctatus) were administered clofibrate or ciprofibrate 48 hr prior to hepatic or trunk kidney (catfish only) microsome preparation. While no significant differences were observed in male catfish, male bluegill had significant decreases in hematocrit and plasma protein indicating hemodilution due to possible gill or kidney damage. Both bluegill and catfish exhibited induction of hepatic and kidney (catfish only) anti-trout lauric acid hydroxylase immunoreactive proteins. In general, total metabolism of lauric acid was greater, and higher levels of wP2, wP3, and wP4 products were produced in control catfish than in juvenile male trout. In male bluegill, lauric acid hydroxylation products wP, wP4 and wP5 were significantly induced by clofibrate treatment. Taken together the above data indicate that peroxisome proliferation may be an important consideration for responsive species exposed to PPAs by environmental chemical contamination.

  20. PREY SELECTIVITY IN WELS (Silurus glanis AND AFRICAN CATFISH (Clarias gariepinus

    Directory of Open Access Journals (Sweden)

    Zdenek Adamek

    1999-06-01

    Full Text Available The experiments aimed at prey selectivity in two Siluriformes predators. African catfish, Clarias gariepinus, and wels, Silurus glanis, were performed under laboratory conditions. Prey fish (12-22% TL of predator were submitted to one.year.old African catfish (~220 g and wels (~150 g originating from intensive culture, ie with no previous experience with live fish food. In African catfish, negative selectivity (avoidance was shown for Nile tilapia (Oreochromis niloticus and topmouth gudgeon (Pseudorasbora parva whilst rudd(Scardinius erythrophthalmus and sunbleak (Leucaspius delineatus were preferred (positive selectivity. The intensity and efficiency of African catfish predation were quite low because its feeding strategy is based rather on prey searching than hunting. Prey fish, wounded and/or dead from its clumsy attacks, were sonsumed preferably overnight. Not one successful attack of African catfish on healthy prey fish was registered. The SGR and FCR of clarias fed live fish were 0.39%. day-1 and 4.73 respectively. In wels, strong negative selectivity (avoidance was proved for roach (Rutilus rutilus and topmouth gungeon, and lower avoidance for Prussian carp (Carassius auratus gibelio and chub (Leuciscus cephalus. Asp (Aspius aspius were found to be low preferred but high preference was shown for sunbleak, rudd and bitterling (Rhodeus sericeus. Both catfishes preferred smaller prey fish during the 10.day experimental period whilst those which remained non-consumed belonged to the mean or above-mean size categories.

  1. Catfish culture in Southeast Asia

    OpenAIRE

    Adan, R. I. Y.

    2000-01-01

    Catfish rank fifth in the world in terms of fresh and brackishwater fish culture. In Asia and the Pacific, the Clariidae family dominates production, representing nearly 80% of the total catfish production. Among the most cultured species are Clarias batrachus, C. macrocephalus, C. gariepinus. The domestic market generally absorbs catfish produce in Asia, although high-producing countries like Thailand and Vietnam engage in export. There are two basic markets for catfish: live fish and proces...

  2. Antioxidative activity of protein hydrolysates prepared from alkaline-aided channel catfish protein isolates.

    Science.gov (United States)

    Theodore, Ann E; Raghavan, Sivakumar; Kristinsson, Hordur G

    2008-08-27

    Antioxidative activity of hydrolyzed protein prepared from alkali-solubilized catfish protein isolates was studied. The isolates were hydrolyzed to 5, 15, and 30% degree of hydrolysis using the protease enzyme, Protamex. Hydrolyzed protein was separated into hydrolysates and soluble supernatants, and both of these fractions were studied for their metal chelating ability, 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging ability, ferric reducing antioxidant power (FRAP), oxygen radical absorbance capacity (ORAC), and their ability to inhibit the formation of thiobarbituric acid reactive substances (TBARS) in washed tilapia muscle containing tilapia hemolysate. Both hydrolysates and supernatants were characterized using sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Results showed that DPPH radical scavenging ability and reducing power of catfish protein hydrolysates decreased, whereas the ORAC value, metal chelating ability, and ability to inhibit TBARS increased, with an increase in the degree of hydrolysis. Hydrolysate samples showed higher DPPH radical scavenging ability and Fe(3+) reducing ability, and supernatant samples had higher metal chelating ability. In general, low molecular weight (MW) peptides had high ORAC values and high metal chelating ability, and high MW peptides had a higher reducing power (FRAP) and were more effective in scavenging DPPH radicals. In a washed muscle model system, the ability of catfish protein hydrolysates and their corresponding supernatants to inhibit the formation of TBARS increased with an increase in the degree of hydrolysis. PMID:18662014

  3. Growing catfish in the Philippines

    OpenAIRE

    Surtida, Marilyn B.; Buendia, Romeo Y.

    2000-01-01

    The catfish industry in the Philippines is budding and projected to expand in the coming years. This is evident from conversations with active catfish farmers who all hope to be able to expand production, whether backyard or commercial because their present production can hardly supply the demands of buyers. NIFTDC, a fisheries technology and development center in Dagupan City, Philippines, however, says that unless the government has a catfish program, expansion of the industry would be slow...

  4. Catfish - King of the sea

    OpenAIRE

    Godø, Olav Rune; Huse, Irene; Michalsen, Kathrine

    1995-01-01

    During an acoustic tagging experiment on cod in the Barents Sea in March 1995 a hierarchy between different fish species was revealed, and the catfish (Anarhichas sp.) was observed to be dominant in relation to cod and haddock. When catfish are present at the fishing grounds, the dominant feeding behaviour of this species might reduce efficiency on other species. If longline catch data are used for stock assessment purposes, the catfish population might therefore be overestimat...

  5. Evaluation of immune responses against the parasite Ichthyophthirius multifiliis between channel catfish and hybrid catfish

    Science.gov (United States)

    Channel catfish is a dominant aquaculture species in the USA and has been cultured for several decades. Recently, an increasing number of producers are showing an interest in the culture of hybrid catfish (channel catfish × blue catfish) instead of channel catfish due to its performance traits. The ...

  6. Tilapia show immunization response against Ich

    Science.gov (United States)

    This study compares the immune response of Nile tilapia and red tilapia against parasite Ichthyophthirius multifiliis (Ich) using a cohabitation challenge model. Both Nile and red tilapia showed strong immune response post immunization with live Ich theronts by IP injection or immersion. Blood serum...

  7. CHANNEL CATFISH INDUSTRY IN THE USA AND THE OFF-FLAVOR PROBLEM

    Directory of Open Access Journals (Sweden)

    Nikola Fijan

    2000-03-01

    Full Text Available The history, the production technology in channel catfish pond farming industry as well as the statistical data on production, processing and product value during past 15 years are presented. The trend of increasing consumption by the population and the presently low prices of grain and soybeans are conductive to further expansion of production. The steady growth of the industry is stimulated by several factors: innovative efforts by farmers, research at the universities and at government institutions some of which have numerous experimental ponds, cooperative extension service for farmers, modern marketing, activities of catfish farming associations, high quality of products from processing plants and vertical integration. The off-flavor in catfish caused by algal metabolites is a major problem in the industry. Genera of algae producing such metabolites, their accumulation in other fish and occurrence in drinking water reservoirs as well as the current emphasis on preventing the entrance of off-flavor contaminated catfish onto the market were reviewed. The main undesirable algal metyabolites are volatile alcohols geosmin and 2-methylisoborneol (MIB. The need for less expensive and quick methods of identifying major off-flavor compounds was pointed out. Research at the University of Arkansas at Pine Bluff, USA, on control of off-flavor algae in experimental ponds by filter-feeding silver carp (Hypophthalmichthys molitrix Val. and tilapias confined in cages showed this approach to be rather promising.

  8. The catfish genome database cBARBEL: an informatic platform for genome biology of ictalurid catfish

    OpenAIRE

    Lu, Jianguo; Peatman, Eric; Yang, Qing; Wang, Shaolin; Hu, Zhiliang; Reecy, James; Kucuktas, Huseyin; Liu, Zhanjiang

    2010-01-01

    The catfish genome database, cBARBEL (abbreviated from catfish Breeder And Researcher Bioinformatics Entry Location) is an online open-access database for genome biology of ictalurid catfish (Ictalurus spp.). It serves as a comprehensive, integrative platform for all aspects of catfish genetics, genomics and related data resources. cBARBEL provides BLAST-based, fuzzy and specific search functions, visualization of catfish linkage, physical and integrated maps, a catfish EST contig viewer with...

  9. Catfish production using intensive aeration

    Science.gov (United States)

    For the last 3 years, researchers at UAPB and NWAC have been monitoring and verifying production yields in intensively aerated catfish ponds with aeration rates greater than 6 hp/acre. We now have three years of data on commercial catfish production in intensively aerated ponds. With stocking densi...

  10. Halogenated Contaminants in Farmed Salmon, Trout, Tilapia, Pangasius, and Shrimp

    NARCIS (Netherlands)

    Leeuwen, van S.P.J.; Velzen, van M.J.M.; Swart, C.P.; Veen, van der I.; Traag, W.A.; Boer, de J.

    2009-01-01

    Polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins and dibenzo-p-furans (PCDD/Fs), organochlorine pesticides (OCPs), polybrominated diphenyl ethers (PBDEs), hexabromocyclododecane diastereomers (HBCDs), and perfluorinated compounds (PFCs) were analyzed in popular farmed fish such as

  11. Carbohydrate metabolism in catfish

    International Nuclear Information System (INIS)

    Radiolabeled (U- 14C)-glucose was incorporated in diets and forced-fed to channel catfish and was observed for a 24 hour period. About 95% of fed labeled (U-14C)-glucose was absorbed by catfish, showing a high digestibility of glucose. The amounts of 14C excreted over 24 h as carbon dioxide were 49% and amounts excreted in urine were 3.5%. The amount retained as protein, fat glycogen and other organic compounds were 8.2, 1.2, 6.5 and 32.1 % respectively, for the 24 hour period. The blood concentration of 14 C reached a maximum 2.5 hour after feeding (U-14C)-glucose, then gradually decreased. Based on tissue concentrations of 14C, glycogen was an immediate storage site for absorbed glucose, but 14C- glycogen in liver decreased rapidly. Glucose was quickly and heavily converted into triglyceride, indicating that fat is an important intermediate in the metabolism of glucose in channel catfish. 14C-fat in the serum and liver were transferred to the adipose tissue in the muscle and mesentery about 10 hours after feeding. (Author)

  12. An epizootic among rainbow trout

    Science.gov (United States)

    1953-01-01

    An epizootic among rainbow trout (Salmo gairdnerii) in a private trout farm, resulting from a species of Ichthyosporidium that caused very high mortality rates in all ages of trout, reported from the State of Washington.

  13. Tilapia Vaccines: Important Disease Prevention, Biosecurity Tools

    Science.gov (United States)

    Minimizing the effects of disease is crucial to prevent mortality, morbidity and to promote rapid growth and optimal feed conversion of tilapia cultured in fresh, estuarine and marine waters. Vaccination, a valuable biosecurity safeguard, can protect tilapia against infectious diseases. Vaccinat...

  14. The Effects of Two Chemo-attractants and Different First Feeds on the Growth Performances of African Catfish (Clarias gariepinus, Burchell, 1822) at Different Larval Stages

    OpenAIRE

    Yilmaz, Erdal

    2005-01-01

    In this study, 4 days old African catfish larvae were fed with trout starter diet, minced beef liver and fresh water mussel, dried tubifex, DL-alanine and betaine supplemented trout starter, artemia nauplii and a combined diet consisting of boiled chicken egg yolk, minced mussel and dried tubifex as the first feed after yolk absorption for a week. At the end of the first period, it was observed that DL-alanine and betaine supplementation did not improve the larval growth and survival compared...

  15. Examining indirect effects of lake trout recovery

    Science.gov (United States)

    With the recovery of lake trout populations in Lake Superior, there are indications of decreased forage fish abundance and density-dependence in lake trout. In Lake Superior, lean lake trout historically occupied depths trout occupied depths > 60 m...

  16. Calcium deprivation during channel catfish, Ictalurus punctatus X blue catfish, I. furcatus F1 hybrid catfish embryo development affects hatching success

    Science.gov (United States)

    Channel x blue hybrid catfish are produced by fertilizing eggs from hormone-induced, strippable channel catfish (Ictalurus punctatus) females with sperm from blue catfish (I. furcatus). Many catfish hatchery supplies have low calcium concentrations and are supplemented with an external source of ca...

  17. Both recombinant African catfish LH and FSH are able to activate the African catfish FSH receptor

    NARCIS (Netherlands)

    Vischer, HF; Granneman, JCM; Linskens, MHK; Schulz, RW; Bogerd, J

    2003-01-01

    LH and FSH are heterodimeric glycoprotein hormones, composed of a common alpha-subunit non-covalently associated with a hormone-specific beta-subunit. Repeated efforts to isolate catfish FSH (cfFSH) have not been successful and only catfish LH (cfLH) has been purified from catfish pituitaries. Recen

  18. Comparative Oxygen Tolerance of Blue Catfish Ictalurus furcatus and Channel Catfish I. punctatus

    Science.gov (United States)

    Blue catfish (Ictalurus furcatus) have several advantages over channel catfish (I. punctatus) as commercial culture fish. They are more resistant to ESC, PGD, and CCVD, major diseases of channel catfish. They are very easy to seine, with a near-total harvest possible with one seine haul, and may ex...

  19. Tilapia breeding in ricefields in Vietnam

    OpenAIRE

    Nguyen, C.D.; Tran, M.T.; Dinh, V.T.

    1997-01-01

    Results of the studies undertaken for breeding and nursing Nile tilapia (Oreochromis niloticus) in ricefields in Thai Binh province in Vietnam during the years 1995-96 are briefly presented in this paper.

  20. Catfish Preservation using Porphyra Yezoensis Composites Preservatives

    OpenAIRE

    Zhi-Gang Qian; Long-Fa Jiang; Li-Qiang Rui

    2013-01-01

    This study aims to preserve fresh catfish meat by using Porphyra Yezoensis extract, chitosan and lactic acid Nisin. The composite preservative obtained by sensory evaluation can effectively maintain the color, odor and texture of fresh catfish meat, as well as inhibit bacterial growth. Results show that treatment using a preservative solution (Porphyra Yezoensis extract 10%, Nisin 0.2% and chitosan 15%) extended the shelf life of the fresh catfish meat from 12 h to 24 h when stored at room te...

  1. Trout Stream Special Regulations

    Data.gov (United States)

    Minnesota Department of Natural Resources — This layer shows Minnesota trout streams that have a special regulation as described in the 2006 Minnesota Fishing Regulations. Road crossings were determined using...

  2. Development and shelf life evaluation of Tilapia (Orechromis spp.) marinades

    OpenAIRE

    Rathnayake, M.M.; Prasadi, V.P.N.; Jayasinghe, C.V.L.

    2012-01-01

    Tilapia (Oreochromis spp.) consumption is limited due to its strong muddy odour and the difficulty of processing. In addition, consumption of tilapia is minimal in urban areas because of the low availability. There are no processed market products of tilapia available in Sri Lanka. Therefore, this study was designed to develop a new marinade for tilapia and to evaluate the shelf life of the product. Twelve different treatments of varying amounts of vinegar, salt, chili powder, white pepper an...

  3. Water quality in hybrid catfish ponds after partial fish harvest

    Science.gov (United States)

    Intensification of United States catfish aquaculture involves hybrid catfish ('channel catfish Ictalurus punctatus x ' blue catfish I. furcatus) grown in ponds with abundant aeration and high feeding rates. High feeding rates cause water quality deterioration because most of the nitrogen, phosphorus...

  4. Pyridoxine requirements of channel catfish.

    Science.gov (United States)

    Andrews, J W; Murai, T

    1979-04-01

    In 20 and 12 week feeding trials, channel catfish fingerlings were fed purified diets containing five levels (0, 5, 10, 20, and 30 mg/kg) and six levels (0, 1, 2, 5, 10, and 20 mg/kg) of supplemental pyridoxine hydrochloride. Fish fed unsupplemented diets (pyridoxine content of 1.2 mg/kg) were characterized by anoxeria, nervous disorders, tetany, greenish-blue body coloration, and eventual mortality. Anemia, which has been reported in pyridoxine deficient salmonids, was not observed in pyridoxine deficient catfish. However, a microcytic, normochromic anemia was observed in groups fed high dietary levels of pyridoxine (20 mg/kg or greater). The dietary pyridoxine level required for maximal growth was approximately 3 mg/kg of diet. All other deficiency signs were prevented by 2.2 mg/kg of diet. PMID:430257

  5. THE EFFECTIVENESS OF STATE LOGOS FOR FARM-RAISED CATFISH

    OpenAIRE

    Schupp, Alvin R.; Dellenbarger, Lynn E.

    1993-01-01

    Product differentiation can consist of identifying the corporate firm that produces the product (such as Kraft) or the producer cooperative that produces the product (such as Ocean Spray). The Catfish Institute (funded by producers, feed mills and processors) was created to promote the generic sales of farm-raised catfish. Also, a number of Mississippi catfish processors are differentiating their product by promoting it as Mississippi Farm-Raised Catfish. Louisiana farm-raised catfish are hig...

  6. Pathogenicity of Streptococcus ictaluri to Channel Catfish

    Science.gov (United States)

    The infectivity of a Streptococcus ictaluri isolate for fry (0.5 g), fingerling (15 g), and juvenile (55 g) channel catfish (Ictalurus punctatus) was determined by bath immersion and injection infectivity experiments. Channel catfish exposed by immersion were exposed to baths containing 1012, 1011,...

  7. Prevalence of pansteatitis in African sharptooth catfish, Clarias gariepinus (Burchell, in the Kruger National Park, South Africa

    Directory of Open Access Journals (Sweden)

    K. David A. Huchzermeyer

    2012-04-01

    Full Text Available Pansteatitis was confirmed in sharptooth catfish, Clarias gariepinus (Burchell, from three main locations within the Kruger National Park (KNP; the Olifants River Gorge, Engelhard Dam on the Letaba River and from the Sabie River in the Sabiepoort. An increasing prevalence of pansteatitis was observed in catfish during repeated samplings from the Olifants Gorge from 2009 to 2011 and co-existence of old and recent lesions indicated on-going incitement of pansteatitis. Only a low prevalence of pansteatitis was observed in catfish sampled from the Olifants River upstream of the Gorge in the KNP and no pansteatitis was observed in catfish sampled from a rain-filled dam not connected to the Olifants River. Common to both the Olifants Gorge and the Sabiepoort is the damming of the rivers in Mozambique to form lakes Massingir and Corumana respectively. Anthropogenic activities resulting in potential pollution of the rivers differ greatly between these two catchments, providing argument against a primary pollution-related aetiology of the pansteatitis found at these two sites. Compared with other sites, analysis of stomach contents of catfish from the Olifants Gorge and the Sabiepoort strongly suggested that consumption of a predominantly fish diet was associated with the development of pansteatitis in these fish. In a farmed population of catfish used as positive control, development of pansteatitis could be ascribed to consumption of rancid fish waste from a trout slaughterhouse. In the Olifants Gorge, alien invasive silver carp, Hypophthalmychthys molitrix (Valenciennes, seasonally migrate upstream out of Lake Massingir to spawn. This schooling species is an obligate phytoplankton feeder with consequent high levels of adipose tissue n-3 polyunsaturated fatty acids. In the Olifants Gorge, at least, this may explain seasonal exposure to levels of polyunsaturated fats in the diets of catfish and crocodiles to which these animals are not adapted. The

  8. Evaluation of stomach tubes and gastric lavage for sampling diets from blue catfish and flathead catfish

    Science.gov (United States)

    Waters, D.S.; Kwak, T.J.; Arnott, J.B.; Pine, William E., III

    2004-01-01

    We compared the ability to extract all stomach contents by using stomach tubes or gastric lavage to sample diets from blue catfish Ictalurus furcatus and flathead catfish Pylodictus olivarus. Pulsed gastric lavage (PGL) removed a significantly greater proportion of stomach content mass (95.6%) from blue catfish than did stomach tubes (14.6%). Percent mass of flathead catfish contents removed with PGL (96.0%) was not significantly different from that removed with stomach tubes (86.9%). Based on the greater effectiveness of PGL for blue catfish, combined with a shorter mean time required per sample (69 versus 118 s) and the better preservation of extracted diet material, we recommend using PGL as a nonlethal technique to collect diet samples from large catfishes.

  9. Complete mitochondrial genome of Zebra tilapia, Tilapia buttikoferi.

    Science.gov (United States)

    Mu, Xi-Dong; Liu, Chao; Wang, Xue-Jie; Liu, Yi; Hu, Yin-Chang; Luo, Jian-Ren

    2016-01-01

    We determined the complete mitochondrial genome of Tilapia buttikoferi, which was 16,577 bp in length with an A + T content of 53.0%, containing 13 protein-coding genes, 2 rRNAs, 22 tRNAs and a complete control region. The gene arrangement was similar to that of typical fishes. The total base composition of the mitogenome was 25.6% T, 30.8% C, 27.4% A and 16.2% G. Of the 13 protein-coding genes, 12 genes start with an ATG codon, except for COX1 with GTG. Seven (ND1, ND2, COX1, ATPase8, ATPase6, ND4L and ND6) used TAA or AGA as the termination codon, whereas six (COX2, COX3, ND3, ND4, ND5 and cyt b) had incomplete stop codon T. Its control region was atypical in being short at 861 bp, and contained TACAT motif and one microsatellite-like region (TA)7. This mitogenome sequence data may be useful for phylogenetic and systematic analyses within the family Cichlaidae. PMID:24438265

  10. Low-fat frankfurters from protein concentrates of tilapia viscera and mechanically separated tilapia meat

    OpenAIRE

    Cavenaghi-Altemio, Angela D; Alcade, Lígia B; Fonseca, Gustavo G

    2013-01-01

    In order to develop a healthy low-fat frankfurter-type sausage, different formulations were developed with tilapia viscera surimi (T1) and two with mechanically separated tilapia meat (MSTM) surimi (T2 and T3), all without pig lard addition. Due to technological problems observed for T1 sausage during cooking, it was not further investigated. The functionality of the other two formulations was evaluated based on proximate composition, pH, water activity, and texture. Finally, microbiological ...

  11. Use of probiotics in diets of Tilapia

    Science.gov (United States)

    AAquaculture is one of the fastest growing sectors of agriculture globally. Production in freshwater and marine fisheries has plateaued, and the continued demand for seafood and need for affordable protein sources in third world countries will ensure growth of aquaculture in the future. Tilapia are ...

  12. The World Demand for Catfish Pangasius

    DEFF Research Database (Denmark)

    Nguyen, Thong Tien; Roth, Eva; Nielsen, Max;

    2014-01-01

    . Direct elasticity including own- and cross- price elasticity and income elasticity are calculated to show how consumers from different markets of the world prefer for the Pangasius catfish. We found that catfish products have big room of market demand, indicated by absolute values of own price......In this paper we present a world demand system for Pangasius catfish products. We use solely exporting data from Vietnam for estimating a non-linear Almost Ideal Demand System because Vietnam accounts for more than 90% catfish export value of the world and the products exported are mostly in...... filleted form. The demand system includes seven equations representing for most important markets that are ASEAN & EAST ASIA, NORTH AMERICA, OCEANIA, RUSIAN & EASTERN EU, SOUTH & CENTRAL AMERICA, WESTERN EU, and ROW (rest of the world) markets. The monthly data are updating from January 2007 to March 2014...

  13. Development of 'Serunding' from African catfish

    DEFF Research Database (Denmark)

    Juhari, Nurul Hanisah Binti; MK, Zainol; MM, Masduki

    This research was conducted to develop serunding from African catfish (Clarias gariepinus). Proximate analysis, physical analysis, ascorbic acid analysis, mineral analysis and sensory evaluation were carried out to determine the nutrient compositions and consumer acceptance towards the products. ...

  14. Development of 'Serunding' from African catfish

    OpenAIRE

    Juhari, Nurul Hanisah Binti; MK, Zainol; MM, Masduki

    2009-01-01

    This research was conducted to develop serunding from African catfish (Clarias gariepinus). Proximate analysis, physical analysis, ascorbic acid analysis, mineral analysis and sensory evaluation were carried out to determine the nutrient compositions and consumer acceptance towards the products. samples of serunding were prepared with 3 different sizes (30-40cm, 40-50cm, 50-60cm) of African catfish and control was prepared using round scad fish ('ikan selayang') with same amount of fish flesh...

  15. Catfish stings: A report of two cases

    OpenAIRE

    Gholamali Dorooshi

    2012-01-01

    Venomous catfish stings are a common environment hazard worldwide. Although these stings are often innocuous, significant morbidity may result from stings, including severe pain, retained foreign bodies, infection, respiratory compromise, arterial hypotension, and cardiac dysrhythmias. Treatment included hot water immersion, analgesia, wound exploration, and prophylactic antibiotics. In this article, two cases of stings by catfish referred to the poison center of Noor Hospital, Isfahan Univer...

  16. Catfish stings: A report of two cases

    Directory of Open Access Journals (Sweden)

    Gholamali Dorooshi

    2012-01-01

    Full Text Available Venomous catfish stings are a common environment hazard worldwide. Although these stings are often innocuous, significant morbidity may result from stings, including severe pain, retained foreign bodies, infection, respiratory compromise, arterial hypotension, and cardiac dysrhythmias. Treatment included hot water immersion, analgesia, wound exploration, and prophylactic antibiotics. In this article, two cases of stings by catfish referred to the poison center of Noor Hospital, Isfahan University of Medical Sciences and their treatments have been reported.

  17. DYNAMIC FACTORS INFLUENCING U.S. AND REGIONAL CATFISH DEMAND

    OpenAIRE

    Houston, Jack E.; Ermita, Isabel

    1992-01-01

    Response to changes in factors influencing consumption of catfish and competing commodities differ between national, South Atlantic, and Southwest Central markets. A modified state adjustment model for catfish, beef, chicken, and other fish explicitly included age distribution, residence, occupation, education, and race/ethnic variables associated with habit formation. Nationally, per capita expenditures on catfish respond to present and past relative prices, and catfish, chicken, and other f...

  18. Recombinant truncated tilapia growth hormone enhances growth and innate immunity in tilapia fry (Oreochromis sp.).

    Science.gov (United States)

    Acosta, Jannel; Carpio, Yamila; Besada, Vladimir; Morales, Reynold; Sánchez, Aniel; Curbelo, Yosvel; Ayala, Julio; Estrada, Mario P

    2008-05-15

    Pichia pastoris cells transformed with a plasmid engineered for the expression of tilapia growth hormone as a secreted product produced a proteolytically cleaved form of the recombinant protein. The sequence of this truncated variant was obtained by mass spectrometry analysis. The cleavage site was determined to be between residues Tyr 158 and Tyr 159. The resulting truncated tilapia growth hormone was a single chain protein lacking 46 amino acids of the C-terminal portion. In this study, we showed that the truncated growth hormone produced in the P. pastoris culture supernatant has growth promoting effects and stimulates innate immune parameters (lysozyme and lectins) in tilapia larvae. These results suggest that the C-terminal portion of growth hormone is not required for its growth promoting activity and the innate immune functions studied herein in fish. In addition, we found that the culture supernatant containing truncated tilapia growth hormone has a stronger effect over growth and immune system than cells lysate containing intact tilapia growth hormone expressed in P. pastoris. PMID:18471813

  19. Comparative production of channel catfish and channel x blue hybrid catfish subjected to two minimum dissolved oxygen concentrations

    Science.gov (United States)

    The effect of daily minimum dissolved oxygen concentration on growth and yield (kg/ha) of the channel catfish (Ictalurus punctatus) and the channel x blue hybrid catfish (I. punctatus female x I. furcatus male), which shared the Jubilee strain of channel catfish as the maternal parent, was evaluated...

  20. The Sea Trout Year 1985

    OpenAIRE

    Fahy, E

    1986-01-01

    The wet year of 1985 yielded good catches to the rod and to commercial engines. Salmon were taken in reasonable numbers in the drift nets although only small numbers of sea trout were captured by this method. The wet angling season is thought to have provided productive fishing conditions contributing largely to a 22% increase over the previous year's landings of sea trout.

  1. Trout in the Classroom

    Science.gov (United States)

    Heath, Thomas

    2014-05-01

    Trout in the Classroom (TIC) is a conservation-oriented environmental education program for elementary, middle, and high school students. During the year each teacher tailors the program to fit his or her curricular needs. Therefore, each TIC program is unique. TIC has interdisciplinary applications in science, social studies, mathematics, language arts, fine arts, and physical education. In the program, students and teachers raise trout from fertilized eggs supplied by Virginia Department of Game and Inland Fisheries (VGIF) hatcheries, in aquariums equipped with special chillers designed to keep the water near 50 degrees F. The students make daily temperature measurements, and monitor pH, dissolved oxygen, conductivity, and ammonia levels. They record their data, plot trends, and make sure that the water quality is sufficient to support trout development. The fingerlings, which hatch in late October, are almost an inch and a half long by mid-January. And towards the end of the school year, students will release the fry into VGIF approved watersheds. TIC programs have been in place all across the country for more than 20 years, and are the result of numerous collaborations between teachers, volunteers, government agencies, and local organizations like Trout Unlimited. The programs were designed specifically for teachers who wanted to incorporate more environmental education into their curriculum. While the immediate goal of Trout in the Classroom is to increase student knowledge of water quality and cold water conservation, its long-term goal is to reconnect an increasingly urbanized population of youth to the system of streams, rivers, and watersheds that sustain them. Successful programs have helped: connect students to their local environments and their local watersheds; teach about watershed health and water quality, and; get students to care about fish and the environment. In Virginia, the TIC program is now in its 8th year. Over the past year, the program

  2. Embryotoxicity of an extract from Great Lakes lake trout to rainbow trout and lake trout

    Energy Technology Data Exchange (ETDEWEB)

    Wright, P.J.; Tillitt, D.E. [National Biological Service, Columbia, MO (United States). Midwest Science Center

    1995-12-31

    Aquatic ecosystems such as the Great Lakes are known to be contaminated with chemicals that are toxic to fish. However, the role of these contaminants in reproductive failures of fishes, such as lake trout recruitment, has remained controvertible. It was the objective to evaluate dioxin-like embryotoxicity of a complex mixture of chemicals and predict their potential to cause the lack of recruitment in Great Lakes lake trout. Graded doses of a complex environmental extract were injected into eggs of both rainbow trout and lake trout. The extract was obtained from whole adult lake trout collected from Lake Michigan in 1988. The extract was embryotoxic in rainbow trout, with LD50 values for Arlee strain and Erwin strain of 33 eggEQ and 14 eggEQ respectively. The LOAEL for hemorrhaging, yolk-sac edema, and craniofacial deformities in rainbow trout were 2, 2, and 4 eggEQ, respectively. Subsequent injections of the extract into lake trout eggs were likewise embryotoxic, with an LD50 value of 7 eggEQ. The LOAEL values for the extract in lake trout for hemorrhaging, yolk-sac edema, and craniofacial deformities were 0.1, 1, and 2 eggEQ, respectively. The current levels of contaminants in lake trout eggs are above the threshold for hemorrhaging and yolk-sac edema. The results also support the use of an additive model of toxicity to quantify PCDDs, PCDFs, Non-o-PCBs, and Mono-o-PCBs in relation to early life stage mortality in Lake Michigan lake trout.

  3. Inhibition of nitrite-induced toxicity in channel catfish by calcium chloride and sodium chloride

    Science.gov (United States)

    Tommasso J.R., Wright, M. I.; Simco, B.A.; Davis, K.B.

    1980-01-01

    Environmental chloride has been shown to inhibit methemoglobin formation in fish, thereby offering a protective effect against nitrite toxicity. Channel catfish (Ictalurus punctatus) were simultaneously exposed to various environmental nitrite and chloride levels (as either CaCl2 or NaCl) in dechlorinated tap water (40 mg/L total hardness, 47 mg/L alkalinity, 4 mg/L chloride, pH = 6.9-7.1, and temperature 21-24°C). Methemoglobin levels in fish simultaneously exposed to 2.5 mg/L nitrite and up to 30 mg/L chloride as either CaCl2 or NaCl were similar but significantly lower than in unprotected fish. Exposure to 10 mg/L nitrite and 60 mg/L chloride resulted in methemoglobin levels similar to those of the controls; most unprotected fish died. Fish exposed to 10 mg/L nitrite had significantly lower methemoglobin levels when protected with 15.0 mg/L chloride as CaCl2 than with NaCl. Fish exposed to nitrite in the presence of 60 mg/L chloride (as either CaCl2 or NaCl) had similar 24-h LC50 values that were significantly elevated above those obtained in the absence of chloride. Calcium had little effect on tolerance to nitrite toxicity in channel catfish in contrast to its large effect reported in steelhead trout (Salmo gairdneri).

  4. The Organoleptic and Smoked Catfish Histology from Pre-cooking

    OpenAIRE

    Venny Yuliastri; Ruddy Suwandi; Uju

    2015-01-01

    Catfish is one of the main commodities in fresh water aquaculture. Indonesia catfish production increased 37,49% in 2010 until 2014. Protein content of catfish is 17.7-26.7% and fat about 0.95 until 11.5%. The objective of this study was to determine the best organoleptic and to study the changes of tissue structure of catfish caused by process precooking and smoking process. Precooked Catfish with variation 5, 10 and 15 minute; temperature of 100oC, and smoked for 7 hours with...

  5. Current Situation and Problems of Export-oriented Tilapia Processing in Guangxi and Countermeasures

    OpenAIRE

    Zhang, Ying; Jiang, Gaozhong; Zhang, Qiong

    2014-01-01

    Guangxi Zhuang Autonomous Region is an excellent area for tilapia breeding in China, and the development of tilapia industry has received high attention of both the state and Guangxi government. The foreign exchange earning is an essential industrial form of tilapia industry in Guangxi. Thus, enhancing the competitiveness of export-oriented tilapia processing is of great significance to the development of tilapia industry. On the basis of field survey, this paper analyzed current situation of...

  6. Thiamin requirement of Nile tilapia (Oreochromis niloticus)

    Science.gov (United States)

    Juvenile Nile tilapia were fed to apparent satiation twice daily with purified diets containing 0, 1.0, 2.0, 4.0, 8.0 and 16.0 mg/kg and 0. 2.0, 4.0, 8.0, 16.0 and 32.0 mg/kg of thiamin in separate 14-week (experiment 1) and 8-week trials (experiment 2), respectively. Fish fed the diet devoid of thi...

  7. Parasitism affects vaccine efficacy against Streptococcus iniae in Nile tilapia

    Science.gov (United States)

    Tilapia culture worldwide is estimated to be US$ 5 billion and is important to domestic and global food security. Parasites and bacteria co-occur in both extensive and intensive production of tilapia. The effect of parasitism on vaccine performance in fish is little studied. The objective of this ...

  8. 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...

  9. Both recombinant African catfish LH and FSH are able to activate the African catfish FSH receptor

    OpenAIRE

    Vischer, HF; Granneman, JCM; Linskens, MHK; Schulz, RW; Bogerd, J

    2003-01-01

    LH and FSH are heterodimeric glycoprotein hormones, composed of a common alpha-subunit non-covalently associated with a hormone-specific beta-subunit. Repeated efforts to isolate catfish FSH (cfFSH) have not been successful and only catfish LH (cfLH) has been purified from catfish pituitaries. Recently, however, we succeeded in cloning the cDNA encoding the putative cfFSHbeta; the cDNAs for the alpha- and beta-subunit of cfLH have been cloned before. Here we report the expression of biologica...

  10. Broad-scale patterns of Brook Trout responses to introduced Brown Trout in New York

    Science.gov (United States)

    McKenna Jr, James E.; Slattery, Michael T.; Kean M. Clifford

    2013-01-01

    Brook Trout Salvelinus fontinalis and Brown Trout Salmo trutta are valuable sport fish that coexist in many parts of the world due to stocking introductions. Causes for the decline of Brook Trout within their native range are not clear but include competition with Brown Trout, habitat alteration, and repetitive stocking practices. New York State contains a large portion of the Brook Trout's native range, where both species are maintained by stocking and other management actions. We used artificial neural network models, regression, principal components analysis, and simulation to evaluate the effects of Brown Trout, environmental conditions, and stocking on the distribution of Brook Trout in the center of their native range. We found evidence for the decline of Brook Trout in the presence of Brown Trout across many watersheds; 22% of sampled reaches where both species were expected to occur contained only Brown Trout. However, a model of the direct relationship between Brook Trout and Brown Trout abundance explained less than 1% of data variation. Ordination showed extensive overlap of Brook Trout and Brown Trout habitat conditions, with only small components of the hypervolume (multidimensional space) being distinctive. Subsequent analysis indicated higher abundances of Brook Trout in highly forested areas, while Brown Trout were more abundant in areas with relatively high proportions of agriculture. Simulation results indicated that direct interactions and habitat conditions were relatively minor factors compared with the effects of repeated stocking of Brown Trout into Brook Trout habitat. Intensive annual stocking of Brown Trout could eliminate resident Brook Trout in less than a decade. Ecological differences, harvest behavior, and other habitat changes can exacerbate Brook Trout losses. Custom stocking scenarios with Brown Trout introductions at relatively low proportions of resident Brook Trout populations may be able to sustain healthy populations of both

  11. CONCURRENT EXPERIMENTAL Streptococcus SPP. INFECTIONS AND NATURAL PARASITISM IN CHANNEL CATFISH Ictalurus punctatus

    Science.gov (United States)

    Streptococcus iniae and S. agalactiae are usually not considered pathogens of channel catfish, Ictalurus punctatus, though concurrent infections may decrease catfish survival when infected with streptococcal organisms. Non-parasitized or naturally-parasitized channel catfish fry were challenged wit...

  12. Towards the ictalurid catfish transcriptome: generation and analysis of 31,215 catfish ESTs

    OpenAIRE

    Dunham Rex; Muir William; Liu Lei; Turan Cemal; Simmons Micah; Serapion Jerry; Somridhivej Benjaporn; Nandi Samiran; Kucuktas Huseyin; Xu Peng; Baoprasertkul Puttharat; He Chongbo; Feng Jinian; Wang Shaolin; Peatman Eric

    2007-01-01

    Abstract Background EST sequencing is one of the most efficient means for gene discovery and molecular marker development, and can be additionally utilized in both comparative genome analysis and evaluation of gene duplications. While much progress has been made in catfish genomics, large-scale EST resources have been lacking. The objectives of this project were to construct primary cDNA libraries, to conduct initial EST sequencing to generate catfish EST resources, and to obtain baseline inf...

  13. Spawning Trout in Eastern Connemara

    OpenAIRE

    Fahy, E.; Nixon, J. J.

    1982-01-01

    Concentrations totalling 299 trout from nine spawning sites in eastern Connemara in 1981 were examined to elucidate the spawning biology of these stocks. Sea trout made up the majority. Brown liveried fish predominated among migratory males (75%) but were few among females (2.5%). Males were of younger sea and river age than females and the ratio of females to males was lowest among the younger age categories. Scars and marks were evenly distributed between the sexes and 51% of females showed...

  14. Identification and characterization of full-length cDNAs in channel catfish (Ictalurus punctatus and blue catfish (Ictalurus furcatus.

    Directory of Open Access Journals (Sweden)

    Fei Chen

    Full Text Available BACKGROUND: Genome annotation projects, gene functional studies, and phylogenetic analyses for a given organism all greatly benefit from access to a validated full-length cDNA resource. While increasingly common in model species, full-length cDNA resources in aquaculture species are scarce. METHODOLOGY AND PRINCIPAL FINDINGS: Through in silico analysis of catfish (Ictalurus spp. ESTs, a total of 10,037 channel catfish and 7,382 blue catfish cDNA clones were identified as potentially encoding full-length cDNAs. Of this set, a total of 1,169 channel catfish and 933 blue catfish full-length cDNA clones were selected for re-sequencing to provide additional coverage and ensure sequence accuracy. A total of 1,745 unique gene transcripts were identified from the full-length cDNA set, including 1,064 gene transcripts from channel catfish and 681 gene transcripts from blue catfish, with 416 transcripts shared between the two closely related species. Full-length sequence characteristics (ortholog conservation, UTR length, Kozak sequence, and conserved motifs of the channel and blue catfish were examined in detail. Comparison of gene ontology composition between full-length cDNAs and all catfish ESTs revealed that the full-length cDNA set is representative of the gene diversity encoded in the catfish transcriptome. CONCLUSIONS: This study describes the first catfish full-length cDNA set constructed from several cDNA libraries. The catfish full-length cDNA sequences, and data gleaned from sequence characteristics analysis, will be a valuable resource for ongoing catfish whole-genome sequencing and future gene-based studies of function and evolution in teleost fishes.

  15. Recent improvements in channel catfish reproduction

    Science.gov (United States)

    Control of reproduction in fish is a primary requisite for reliable, predictable and quality seed stock for aquaculture production or a stock enhancement program. Channel catfish is the leading aquaculture species in USA, accounting for 335 million pounds with a farm gate value of over $ 400 millio...

  16. Cart Regulates Food Intake in Channel Catfish

    Science.gov (United States)

    Cocaine-and Amphetamine-Regulated Transcript (CART) is a potent hypothalamic anorectic peptide in mammals and fish. We hypothesized that increased food intake is associated with changes in expression of CART mRNA within the brain of channel catfish. Objectives were to clone the CART gene, examine ...

  17. The Innate Immune-Related Genes in Catfish

    OpenAIRE

    Weidong Liu; Xianggang Gao; Yunfeng Li; Hao Su; Xueguang Liu; Chongbo He; Lei Gao

    2012-01-01

    Catfish is one of the most important aquaculture species in America (as well as in Asia and Africa). In recent years, the production of catfish has suffered massive financial losses due to pathogen spread and breakouts. Innate immunity plays a crucial role in increasing resistance to pathogenic organisms and has generated increasing interest in the past few years. This review summarizes the current understanding of innate immune-related genes in catfish, including pattern recognition receptor...

  18. Comparative Histomorphological Studies on Oesophagus of Catfish and Grass Carp

    OpenAIRE

    Enas A. Abd El Hafez; Doaa M. Mokhtar; Alaa Sayed Abou-Elhamd; Ahmed Hassan S. Hassan

    2013-01-01

    The present work was carried out on 40 specimens of oesophaguses of both sexes of catfish (carnivorous fish) and grass carp (herbivorous fish) in order to observe the morphological and histological differences between the two species. Oesophagus of catfish was divided into 2 parts: anterior and posterior ones. The anterior part of the oesophagus of catfish was characterized by the presence of numerous mucosal folds. It was lined by stratified epithelium with goblet cells. In addition to club ...

  19. Welfare of African catfish : effects of stocking density

    OpenAIRE

    Nieuwegiessen, van de, P.G.

    2009-01-01

    The general aim of this thesis was to determine the impact of stocking density on welfare indicators in African catfish, Clarias gariepinus, cultured in a recirculating aquaculture system. The following factors were studied: 1) the effects of stocking density on physical, physiological, and behavioural responses of African catfish, 2) how age mediates the effects of stocking density on physical, physiological, and behavioural responses of African catfish, 3) the potential effects of chemical ...

  20. Do Rainbow Trout and Their Hybrids Outcompete Cutthroat Trout in a Lentic Ecosystem?

    OpenAIRE

    Courtney, Joshua M.; Courtney, Amy C.; Courtney, Michael W.

    2013-01-01

    Much has been written about introduced rainbow trout interbreeding and outcompeting native cutthroat trout. However, specific mechanisms have not been thoroughly explored, and most data is limited to lotic ecosystems. Samples of Snake River cutthroat trout (Oncorhynchus clarkii bouvieri), the rainbow-cutthroat hybrid, the cutbow trout (Onchorhynchus mykiss x clarkii), and rainbow trout (Oncorhynchus mykiss), were obtained from a lentic ecosystem (Eleven Mile Reservoir, Colorado) by creel surv...

  1. High-throughput cryopreservation of spermatozoa of blue catfish (Ictalurus furcatus): establishment of an approach for commercial-scale processing

    OpenAIRE

    Hu, E.; Yang, Huiping; Tiersch, Terrence R.

    2010-01-01

    Hybrid catfish created by crossing of female channel catfish (Ictalurus punctatus) and male blue catfish (Ictalurus furcatus) are being used increasingly in foodfish aquaculture because of their fast growth and efficient food conversion. However, the availability of blue catfish males is limited, and their peak spawning is at a different time than that of the channel catfish. As such, cryopreservation of sperm of blue catfish could improve production of hybrid catfish, and has been studied in...

  2. Inactivation of Salmonellae in Frozen Catfish by Gamma Irradiation

    International Nuclear Information System (INIS)

    The effect of gamma irradiation on salmonellae viability in frozen catfish was investigated using fresh cut of catfish artificially contaminated with stationary phase cells of salmonellae, frozen at-18 οC and irradiated with does ranging from 0.0 to 2.4 kGy. The D10 values for ten serovars of salmonellae ranged from 0.47 to 0.77 kGy. Salmonella Enteritidis was the most resistant serovars found in frozen catfish. Dosage at 2.5 kGy would be sufficient to kill 103.2 Salmonella Enteritidis that may occasionally present in frozen catfish

  3. 33 CFR 117.337 - Trout River.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Trout River. 117.337 Section 117... OPERATION REGULATIONS Specific Requirements Florida § 117.337 Trout River. The draw of the CSX Railroad Bridge across the Trout River, mile 0.9 at Jacksonville, operates as follows: (a) The bridge is...

  4. Biological Safety of Fish (Tilapia Collagen

    Directory of Open Access Journals (Sweden)

    Kohei Yamamoto

    2014-01-01

    Full Text Available Marine collagen derived from fish scales, skin, and bone has been widely investigated for application as a scaffold and carrier due to its bioactive properties, including excellent biocompatibility, low antigenicity, and high biodegradability and cell growth potential. Fish type I collagen is an effective material as a biodegradable scaffold or spacer replicating the natural extracellular matrix, which serves to spatially organize cells, providing them with environmental signals and directing site-specific cellular regulation. This study was conducted to confirm the safety of fish (tilapia atelocollagen for use in clinical application. We performed in vitro and in vivo biological studies of medical materials to investigate the safety of fish collagen. The extract of fish collagen gel was examined to clarify its sterility. All present sterility tests concerning bacteria and viruses (including endotoxin yielded negative results, and all evaluations of cell toxicity, sensitization, chromosomal aberrations, intracutaneous reactions, acute systemic toxicity, pyrogenic reactions, and hemolysis were negative according to the criteria of the ISO and the http://dx.doi.org/10.13039/501100003478 Ministry of Health, Labour and Welfare. The present study demonstrated that atelocollagen prepared from tilapia is a promising biomaterial for use as a scaffold in regenerative medicine.

  5. Biological safety of fish (tilapia) collagen.

    Science.gov (United States)

    Yamamoto, Kohei; Igawa, Kazunari; Sugimoto, Kouji; Yoshizawa, Yuu; Yanagiguchi, Kajiro; Ikeda, Takeshi; Yamada, Shizuka; Hayashi, Yoshihiko

    2014-01-01

    Marine collagen derived from fish scales, skin, and bone has been widely investigated for application as a scaffold and carrier due to its bioactive properties, including excellent biocompatibility, low antigenicity, and high biodegradability and cell growth potential. Fish type I collagen is an effective material as a biodegradable scaffold or spacer replicating the natural extracellular matrix, which serves to spatially organize cells, providing them with environmental signals and directing site-specific cellular regulation. This study was conducted to confirm the safety of fish (tilapia) atelocollagen for use in clinical application. We performed in vitro and in vivo biological studies of medical materials to investigate the safety of fish collagen. The extract of fish collagen gel was examined to clarify its sterility. All present sterility tests concerning bacteria and viruses (including endotoxin) yielded negative results, and all evaluations of cell toxicity, sensitization, chromosomal aberrations, intracutaneous reactions, acute systemic toxicity, pyrogenic reactions, and hemolysis were negative according to the criteria of the ISO and the Ministry of Health, Labour and Welfare of Japan. The present study demonstrated that atelocollagen prepared from tilapia is a promising biomaterial for use as a scaffold in regenerative medicine. PMID:24809058

  6. Weight-Length Relationships in Gafftopsail Catfish (Bagre marinus) and Hardhead Catfish (Ariopsis felis) in Louisiana Waters

    OpenAIRE

    Courtney, Joshua; Klinkmann, Taylor; Torano, Joseph; 2; Courtney, Michael

    2012-01-01

    In spite of the abundance and commercial importance of these two species, there is little published weight-length data for the gafftopsail catfish (Bagre marinus) and hardhead catfish (Ariopsis felis). For this study 84 catfish were caught (hook and line) from the Calcasieu Estuary in Southwest Louisiana near the Gulf of Mexico and estuaries and near shore waters close to bayou Lafourche. Using least squares regression, best fit curves were determined for weight (W) vs. total length (L) relat...

  7. Ecological risk assessment of the antibiotic enrofloxacin applied to Pangasius catfish farms in the Mekong Delta, Vietnam.

    Science.gov (United States)

    Andrieu, Margot; Rico, Andreu; Phu, Tran Minh; Huong, Do Thi Thanh; Phuong, Nguyen Thanh; Van den Brink, Paul J

    2015-01-01

    Antibiotics applied in aquaculture production may be released into the environment and contribute to the deterioration of surrounding aquatic ecosystems. In the present study, we assessed the ecological risks posed by the use of the antibiotic enrofloxacin (ENR), and its main metabolite ciprofloxacin (CIP), in a Pangasius catfish farm in the Mekong Delta region, Vietnam. Water and sediment samples were collected in a stream receiving effluents from a Pangasius catfish farm that had applied ENR. The toxicity of ENR and CIP was assessed on three tropical aquatic species: the green-algae Chlorella sp. (72 h - growth inhibition test), the micro-invertebrate Moina macrocopa (48 h - immobilization test), and the Nile tilapia (Oreochromis niloticus). The toxic effects on O. niloticus were evaluated by measuring the cholinesterase (ChE) and catalase (CAT) activities in the fish brain and muscles, respectively, and by considering feed exposure and water exposure separately. Ecological risks were assessed by comparing maximum exposure concentrations with predicted no effect concentrations for cyanobacteria, green algae, invertebrates and fish derived with available toxicity data. The results of this study showed that maximum antibiotic concentrations in Pangasius catfish farm effluents were 0.68 μg L(-1) for ENR and 0.25 μg L(-1) for CIP (dissolved water concentrations). Antibiotics accumulated in sediments down-stream the effluent discharge point at concentrations up to 2590 μg kg(-1) d.w. and 592 μg kg(-1) d.w. for ENR and CIP, respectively. The calculated EC50 values for ENR and CIP were 111000 and 23000 μg L(-1) for Chlorella sp., and 69000 and 71000 μg L(-1) for M. macrocopa, respectively. Significant effects on the ChE and CAT enzymatic activities of O. niloticus were observed at 5 g kg(-1) feed and 400-50000 μg L(-1), for both antibiotics. The results of the ecological risk assessment performed in this study indicated only minor risks for cyanobacteria

  8. Optimisation of selective breeding program for Nile tilapia (Oreochromis niloticus)

    OpenAIRE

    Trong, T.Q.

    2013-01-01

      The aim of this thesis was to optimise the selective breeding program for Nile tilapia in the Mekong Delta region of Vietnam. Two breeding schemes, the “classic” BLUP scheme following the GIFT method (with pair mating) and a rotational mating scheme with own performance selection and natural group spawning, were investigated. In the latter scheme, the aim was to mimic natural spawning conditions of Nile tilapia to reduce the time for family production; however reconstructio...

  9. Tol2-mediated transgenesis in tilapia (Oreochromis niloticus)

    OpenAIRE

    Fujimura, Koji; Kocher, Thomas D.

    2011-01-01

    The Nile tilapia (Oreochromis niloticus) is an important species in aquaculture and an excellent model system for laboratory studies. Functional genetic analysis using this species has been difficult because existing methods for producing transgenics are inefficient. Here we show that the Tol2 transposon system can be used to create transgenic tilapia with high efficiency. We constructed a line that is transgenic for GFP under control of a Xenopus elongation factor 1α (EF1α) promoter. The ger...

  10. Efficiency of aquatic macrophytes to treat Nile tilapia pond effluents

    OpenAIRE

    Henry-Silva Gustavo Gonzaga; Camargo Antonio Fernando Monteiro

    2006-01-01

    The effluents from fish farming can increase the quantity of suspended solids and promote the enrichment of nitrogen and phosphorus in aquatic ecosystems. In this context, the aim of this work was to evaluate the efficiency of three species of floating aquatic macrophytes (Eichhornia crassipes, Pistia stratiotes and Salvinia molesta) to treat effluents from Nile tilapia culture ponds. The effluent originated from a 1,000-m² pond stocked with 2,000 male Nile tilapia Oreochromis niloticus. The ...

  11. The Characterization of Fish (Tilapia) Collagen Sponge as a Biomaterial

    OpenAIRE

    Kohei Yamamoto; Yuu Yoshizawa; Kajiro Yanagiguchi; Takeshi Ikeda; Shizuka Yamada; Yoshihiko Hayashi

    2015-01-01

    For scaffold manufacturing, the utility of bioactive natural organic materials derived from marine products is useful and indispensable as an alternative to bovine collagen. The weakest feature of fish collagen for scaffold application is its low degeneration temperature (Td), indicating poor stability of fish collagen in mammals in vivo. We have focused on the tropical fish tilapia as a candidate for generating a clinical scaffold. The aim of this study was to confirm the Td of tilapia type ...

  12. Environmental blue light prevents stress in the fish Nile tilapia

    OpenAIRE

    Volpato G.L.; Barreto R.E.

    2001-01-01

    The present study aimed to test the effects of blue, green or white light on the stress response of the Nile tilapia, Oreochromis niloticus (L.). Each color was tested on two groups of isolated adult Nile tilapia (8 replicates each): one being subjected to confinement stress, and the other not (control). A different environmental color was imposed on each compartment by covering the light source with cellophane of the respective color (green or blue; no cellophane was used for white light). T...

  13. Comparative susceptibility of Channel Catfish, Blue Catfish, and their hybrid cross to experimental challenge with Bolbophorus damnificus (Digenea: Bolbophoridae) cercariae.

    Science.gov (United States)

    Griffin, Matt J; Reichley, Stephen R; Khoo, Lester H; Ware, Cynthia; Greenway, Terrence E; Mischke, Charles C; Wise, David J

    2014-06-01

    The digenetic trematode Bolbophorus damnificus has been implicated in significant losses in catfish aquaculture since the late 1990s. The complex life cycle sequentially involves the American white pelican Pelecanus erythrorhynchos, the marsh rams horn snail Planorbella trivolvis, and Channel Catfish Ictalurus punctatus. Research supports anecdotal reports from the industry, suggesting that the hybrid of Channel Catfish×Blue Catfish I. furcatus is less susceptible to disease agents that have been historically prohibitive to Channel Catfish production, namely the gram-negative bacteria Edwardsiella ictaluri and Flavobacterium columnare, as well as the myxozoan parasite Henneguya ictaluri. This current research compared the susceptibility of Channel Catfish, Blue Catfish, and their hybrid cross to an experimental challenge by B. damnificus. Fish were exposed to 0, 100, 200, and 400 B. damnificus cercariae per fish, and the numbers of metacercariae per fish were determined 14 d postchallenge. Metacercariae were recovered from all challenged fish. There were no significant differences among fish groups challenged with the same dose, suggesting Channel and Blue Catfish and their hybrid are comparably susceptible to B. damnificus infection. As such, it is recommended that producers raising hybrid catfish remain diligent in controlling populations of the snail intermediate host to prevent production losses attributed to B. damnificus, especially when loafing pelicans have been observed at the aquaculture operation. PMID:24895863

  14. EXTRACTION AND DETERMINATION OF COLLAGEN PEPTIDE AND ITS CLINICAL IMPORTANCE FROM TILAPIA FISH SCALES (OREOCHROMIS NILOTICUS)

    OpenAIRE

    M. Hemanth kumar; V. Spandana; Tiwari Poonam

    2011-01-01

    Tilapia are one of the most widely introduced fish globally that has clearly emerged as a very promising group in aquaculture. Oreochromis mossambicus was the first tilapia species to be taken up for large scale aquaculture, followed by Oreochromis niloticus, Oreochromis aureus and Tilapia rendalli. Today O. niloticus contributes more than 80% of tilapia aquaculture production globally. O. mossambicus was introduced in India as early as 1952 with a view to filling some unoccupied ecological n...

  15. A STUDY ON TROUT BREEDING IN DUZCE PROVINCE

    OpenAIRE

    Akbulut, Süleyman; KETEN, Akif

    2009-01-01

    In this study, trout breeding facilities of Duzce Province, a suitable place for trout breeding, were evaluated. As a result of this evaluation, current status, capacities, and problems of trout breeding facilities were determined. Some suggestions were provided to solve these problems and increase the capacity of trout breeding facilities. Keywords: Duzce, Trout Breeding.

  16. Natural mating in Nile tilapia (Oreochromis niloticus L.) : implications for reproductive success, inbreeding and cannibalism

    NARCIS (Netherlands)

    Fessehaye, Y.

    2006-01-01

    Niletilapia ( Oreochromis niloticus L.) is one of the most important species among the commercially farmed tilapias. Both small-scale and commercial production of tilapia is rapidly expanding in many countries of the world because t

  17. Aggression and mortality among Nile tilapia (Oreochromis niloticus) maintained in the laboratory at different densities

    Science.gov (United States)

    Because Nile tilapia (Oreochromis niloticus) density may affect stress levels, metabolism, and survival among tilapia in experimental studies and thus may affect experimental results, tilapia were held in a commonly-used commercial tank system to assess the relationship between fish density and beha...

  18. Fecal strings Associated with Streptococcus agalactiae Infection in Nile Tilapia, Oreochromis niloticus

    Science.gov (United States)

    Nile tilapia (Oreochromis niloticus) were experimentally-infected with Streptococcus agalactiae for several infectivity and vaccine studies. Some of the S. agalactiae-infected tilapia produced considerably longer (up to 20 cm in length) fecal waste strings than historically observed from tilapia at...

  19. Pre-spawning carotenoid fortified diets improve reproductive traits of channel catfish, Ictalurus punctatus and subsequent progeny performance

    Science.gov (United States)

    Availability of consistent number of ovulatory competent channel catfish females is a pre-requisite for efficient production of channel catfish ' x blue catfish, I.furcatus ') hybrid in hatcheries. Raising hybrid catfish in production ponds enables the catfish farmer to harness improved growth rate...

  20. Nutritional Regulation of IGFs in Channel Catfish

    Science.gov (United States)

    We examined changes in hepatic IGF-I and IGF-II mRNA, insulin like growth factor binding proteins (IGFBP-1 and IGFBP-2) mRNA, muscle IGF-I and IGF-II mRNA in fed (fed daily for 45 days) and restricted (not fed for 30 days followed by feeding for 15 days) channel catfish. By day 30, liver IGF-I mRNA...

  1. Changes in Price Behavior in the U.S. Catfish Industry: Evidence Using Cointegration

    OpenAIRE

    Hudson, Darren

    1998-01-01

    The implications of market development in the catfish industry on catfish price behavior are explored using cointegration. It is hypothesized that market development, through increases in competition between processors and shifts in consumer preferences toward fish, has caused changes in price behavior among levels of the catfish market. Using monthly catfish price data, a cointegration analysis of subsets of prices shows that price behavior has changed through time, with catfish prices becom...

  2. Use of Molecular Markers for Catfish Production and Product Quality

    Science.gov (United States)

    Channel catfish are a diploid species native to North America and the primary product of U.S. aquaculture, and molecular genetic research supports selective breeding of catfish for commercial production. To date, short tandem repeat loci have been used to characterize DNA sequence variation within ...

  3. Production Practices of Commercial Catfish Producers in Northeast Louisiana.

    Science.gov (United States)

    Letlow, Richard M.; Verma, Satish

    A study determined the yields obtained and the production practices followed by Louisiana commercial catfish farmers in Catahoula, Concordia, and Franklin Parishes. This information was used by the Louisiana Cooperative Extension Service (LCES) faculty to develop a catfish education program. The study: (1) determined use of selected recommended…

  4. Cannibalism in single-batch hybrid catfish production ponds

    Science.gov (United States)

    Hybrid catfish are more efficiently harvested by seining than are Channel Catfish. Due to that, and their faster growth, hybrids are typically produced in “single-batch” production systems, either in intensively-aerated commercial ponds or in split-pond systems. In either production system, hybrids...

  5. A liquid oxygen calculator for fasted channel catfish

    Science.gov (United States)

    A review of scientific literature concerning channel catfish Ictalurus punctatus respiration resulted in development of a Microsoft Excel© spreadsheet for estimating the volume of oxygen consumed by a given fasted channel catfish biomass. Entry of ten variables into the spreadsheet provides estimate...

  6. Safety of copper sulfate to channel catfish eggs

    Science.gov (United States)

    Copper sulfate (CuSO4) is commonly used in the catfish industry to control saprolegniasis (caused by watermolds) on eggs. This study was designed to establish the safety of CuSO4 when applied to hatching troughs containing channel catfish eggs in 26 degrees C flow-through well water at 10, 30, and ...

  7. Streptococcus agalactiae infection in tilapia (Oreochromis niloticus

    Directory of Open Access Journals (Sweden)

    Suanyuk, N.

    2005-02-01

    Full Text Available Streptococcus agalactiae was isolated from cultured tilapia in Surat Thani province. Isolates were Gram-positive cocci, catalase negative, alpha-haemolytic and serogroup B. Streptococcal-infected fish showed various swimming abnormalities such as swimming on their side, erratic surface or bottom swimming including serpentine movement, exophthalmia and opacity. Internally, splenomegaly, ascites as well as pale liver discoloration were observed. Fish experimentally infected by peritoneal injection using 101 -108 CFU/ fish showed 20-90% mortality within 10 days and the LD50 was 3.60x101 - 1.72x107 CFU. Haematocrit, haemoglobin, plasma protein and blood cell values of infected and moribund fish were significantly decreased. Histopathological findings included the occurrence of inflammation, cells necrosis, infiltration of lymphocytes and the formation of granulomas in the infected organs.

  8. Reductions in Susceptibility of Channel Catfish (Ictalutus punctatus) to Enteric Septicemia of Catfish (ESC) Through Two Generations of Selection

    Science.gov (United States)

    Improvement of disease resistance in aquaculture species through selective breeding has had some success. At the USDA-ARS Catfish Genetics Research Unit, Stoneville, MS, a multitrait selection index was utilized to select for growth, carcass yield, and resistance to enteric septicemia of catfish (...

  9. 76 FR 26655 - Public Meetings on the Proposed Rule for Mandatory Inspection of Catfish and Catfish Products

    Science.gov (United States)

    2011-05-09

    ... meetings, interested persons may submit comments on the proposed rule (76 FR 10434) on or before June 24..., 552, 555, 557, and 559-561 Public Meetings on the Proposed Rule for Mandatory Inspection of Catfish and Catfish Products AGENCY: Food Safety and Inspection Service, USDA. ACTION: Notice of...

  10. First Season Catfish Farming. A Workbook for Beginning Pond and Cage Culture of Channel Catfish. Teacher Edition and Student Edition.

    Science.gov (United States)

    Oklahoma State Board of Vocational and Technical Education, Stillwater. Curriculum and Instructional Materials Center.

    This workbook, comprised of both the teacher and student editions, presents guidelines useful for first-year catfish farmers in Oklahoma using pond or cage cultures to raise channel catfish. The teacher edition is a set of unit guidelines only. Contents include a list of suggested readings, important addresses with types of information available…

  11. Production of channel catfish and channel x blue hybrid catfish subjected to two minimum dissolved oxygen concentrations

    Science.gov (United States)

    As the channel x blue hybrid catfish is stocked by an increasing number of catfish farmers, it is important to quantify the production response of this fish to dissolved oxygen management strategies. The purpose of this study was to compare the production and water quality responses of the channel x...

  12. PROTECTIVE EFFECT OF CUTANEOUS ANTIBODY PRODUCED BY CHANNEL CATFISH IMMUNE TO ICHTHYOPHTHIRIUS ON COHABITED NON-IMMUNE CATFISH

    Science.gov (United States)

    Fish recovered from sublethal ichthyophthiriasis acquire protective immunity against Ichthyophthirius (Ich). This study evaluated the protective effect of cutaneous antibody excreted by channel catfish immune to Ich on cohabited non-immune catfish. Non-immune and immune fish controls were separatel...

  13. "No evidence for intercohort cannibalism in mixed-size cultures of food-size and fingerling hybrid catfish (channel catfish x blue catfish) grown in ponds in winter or summer."

    Science.gov (United States)

    Hybrid catfish (' Channel Catfish Ictalurus punctatus X ' Blue Catfish I. furcatus) are normally harvested by seining single-batch pond production systems in fall or winter. Ponds are typically restocked without draining. There is concern that without completely draining the pond after harvest, food...

  14. Radio-transmitted electromyogram signals as indicators of swimming speed in lake trout and brown trout

    DEFF Research Database (Denmark)

    Thorstad, E.B.; Økland, F.; Koed, Anders;

    2000-01-01

    Swimming speed and average electromyogram (EMG) pulse intervals were highly correlated in individual lake trout Salvelinus namaycush (r(2)=0.52-0.89) and brown trout Salmo trutta (r(2)=0.45-0.96). High correlations were found also for pooled data in both lake trout (r(2)=0.90) and brown trout of...... the Ema stock (r(2)=0.96) and Laerdal stock (r(2)=0.96). The linear relationship between swimming speed and average EMG pulse intervals differed significantly among lake trout and the brown trout stocks. This successful calibration of EMGs to swimming speed opens the possibility of recording swimming...... speed of free swimming lake trout and brown trout in situ. EMGs can also be calibrated to oxygen consumption to record energy expenditure. (C) 2000 The Fisheries Society of the British Isles...

  15. Survival of Trout Strains as Affected by Limnological Parameters

    OpenAIRE

    Wurtsbaugh, Wayne A.

    1988-01-01

    Prior work at East Canyon Reservoir, Utah indicated that adult trout are important predators of stocked juvenile rainbow trout. Brown trout, in particular, were exclusively piscivorous when th~y exceeded 185 mm standard length. Fish became increasingly important in the diet of cutthroat trout greater than 330 mm. The purpose of this study was to further document the effect of adult trout on survival of juvenile rainbow trout in mid-elevation reservoirs. Causey Reservoir was chosen because it ...

  16. Inapparent Streptococcus agalactiae infection in adult/commercial tilapia.

    Science.gov (United States)

    Sun, Jiufeng; Fang, Wei; Ke, Bixia; He, Dongmei; Liang, Yuheng; Ning, Dan; Tan, Hailing; Peng, Hualin; Wang, Yunxin; Ma, Yazhou; Ke, Changwen; Deng, Xiaoling

    2016-01-01

    We report on inapparent infections in adult/commercial tilapia in major tilapia fish farms in Guangdong. A total of 146 suspected isolates were confirmed to be S. agalactiae using an API 20 Strep system and specific PCR amplification. All isolates were identified as serotype Ia using multiplex serotyping PCR. An MLST assay showed single alleles of adhP (10), atr (2), glcK (2), glnA (1), pheS (1), sdhA (3) and tkt (2), and this profile was designated 'unique ST 7'. The analysis of virulence genes resulted in 10 clusters, of which dltr-bca-sodA-spb1-cfb-bac (62, 42.47%) was the predominant virulence gene profile. The PFGE analysis of S. agalactiae yielded 6 distinct PFGE types (A, B, C, D, F and G), of which Pattern C (103) was the predominant type, accounting for approximately 70.55% (103/146) of the total S. agalactiae strains. Therefore, unlike what has been found in juvenile tilapia, in which PFGE pattern D/F is the major prevalent pattern, we found that pattern C was the major prevalent pattern in inapparent infected adult/commercial tilapia in Guangdong, China. In conclusion, we close a gap in the current understanding of S. agalactiae epidemiology and propose that researchers should be alert for inapparent S. agalactiae infections in adult/commercial tilapia to prevent a potential threat to food safety. PMID:27215811

  17. Risks for fishborne zoonotic trematodes in tilapia production systems in Guangdong province, China

    DEFF Research Database (Denmark)

    Li, Kang; Clausen, Jesper Hedegaard; Murrell, Kenneth Darwin; Liu, Liping; Dalsgaard, Anders

    Guangdong province is the most important region for tilapia culture in China. However, it is also an endemic region for fishborne zoonotic trematodes (FZT), which pose a risk to human food safety and health. A study was designed to assess the status of trematode parasite infections in tilapia...... aquaculture systems as an indicator of potential risks from FZT associated with consumption of tilapia. Tilapia from nursery and grow-out ponds were sampled from monoculture, polyculture and integrated aquaculture systems. The results from 388 tilapia examined revealed a very low prevalence (1.5%) of...... tilapia are generally effective in preventing transmission of these parasites into tilapia production systems, the improvement of pond management practices and biosecurity must be maintained at a high level. © 2013 Elsevier B.V. All rights reserved....

  18. Reproductive strategies of two invasive tilapia species Oreochromis mossambicus and Tilapia mariae in northern Australia.

    Science.gov (United States)

    Russell, D J; Thuesen, P A; Thomson, F E

    2012-05-01

    The reproductive biology of two invasive tilapia species, Oreochromis mossambicus and Tilapia mariae, resident in freshwater habitats in north-eastern Australia was investigated. Oreochromis mossambicus exhibited plasticity in some of its life-history characteristics that enhanced its ability to occupy a range of habitats. These included a shallow, weed-choked, freshwater coastal drain that was subject to temperature and dissolved oxygen extremes and water-level fluctuations to cooler, relatively high-altitude impoundments. Adaptations to harsher conditions included a decreased total length (L(T) ) and age (A) at 50% maturity (m50), short somatic growth intervals, early maturation and higher relative fecundities. Potential fecundity in both species was relatively low, but parental care ensured high survival rates of both eggs and larvae. No significant difference in the relative fecundity of T. mariae populations in a large impoundment and a coastal river was found, but there were significant differences in relative fecundities between several of the O. mossambicus populations sampled. Total length (L(T) ) and age at 50% maturity of O. mossambicus populations varied considerably depending on habitat. The L(Tm50) and A(m50) values for male and female O. mossambicus in a large impoundment were considerably greater than for those resident in a small coastal drain. Monthly gonad developmental stages and gonado-somatic indices suggested that in coastal areas, spawning of O. mossambicus and T. mariae occurred throughout most of the year while in cooler, high-altitude impoundments, spawning peaked in the warmer, summer months. The contribution these reproductive characteristics make to the success of both species as colonizers is discussed in the context of future control and management options for tilapia incursions in Australia. PMID:22551176

  19. Copper uptake across rainbow trout gills: mechanisms of apical entry

    DEFF Research Database (Denmark)

    Grosell, Martin Hautopp; Wood, C. M.

    2002-01-01

    Copper, Homeostasis, sodium uptake, copper/sodium interactions, gill, rainbow trout, Oncorhynchus mykiss......Copper, Homeostasis, sodium uptake, copper/sodium interactions, gill, rainbow trout, Oncorhynchus mykiss...

  20. An AFLP-based genetic linkage map of channel catfish (Ictalurus punctatus) constructed by using an interspecific hybrid resource family.

    OpenAIRE

    Liu, Zhanjiang; Karsi, Attila; Li, Ping; Cao, Dongfeng; Dunham, R

    2003-01-01

    Catfish is the major aquaculture species in the United States. The hybrid catfish produced by crossing channel catfish females with blue catfish males exhibit a number of desirable production traits, but their mass production has been difficult. To introduce desirable genes from blue catfish into channel catfish through introgression, a genetic linkage map is helpful. In this project, a genetic linkage map was constructed using amplified fragment length polymorphism (AFLP). A total of 607 AFL...

  1. Swimming endurance of bull trout, lake trout, arctic char, and rainbow trout following challenge with Renibacterium salmoninarum

    Science.gov (United States)

    Jones, D.T.; Moffitt, C.M.

    2004-01-01

    We tested the swimming endurance of juvenile bull trout Salvelinus confluentus, lake trout S. namaycush, Arctic char S. alpinus, and rainbow trout Oncorhynchus mykiss at 9??C and 15??C to determine whether sublethal infection from a moderate challenge of Renibacterium salmoninarum administered months before testing affected the length of time fish could maintain a swimming speed of 5-6 body lengths per second in an experimental flume. Rainbow trout and Arctic char swam longer in trials than did bull trout or lake trout, regardless of challenge treatment. When we tested fish 14-23 weeks postchallenge, we found no measurable effect of R. salmoninarum on the swimming endurance of the study species except for bull trout, which showed a mixed response. We conducted additional trials with bull trout 5-8 weeks postchallenge to determine whether increasing the challenge dose would affect swimming endurance and hematocrit. In those tests, bull trout with clinical signs of disease and those exposed to the highest challenge doses had significantly reduced swimming endurance compared with unchallenged control fish. Fish hematocrit levels measured at the end of all swimming endurance tests varied among species and between test temperatures, and patterns were not always consistent between challenged and control fish.

  2. Larger eggs in resident brown trout living in sympatry with anadromous brown trout

    DEFF Research Database (Denmark)

    Olofsson, H.; Mosegaard, Henrik

    1999-01-01

    Freshwater resident brown trout (Salmo trutta L.) in the stream Jorlandaan (southwestern Sweden) had larger eggs (range of actual mean egg wet weights, 65.9-108.5 mg) than both sympatric migratory trout (76.8-84.2 mg) and trout from five other Swedish streams with allopatric resident (23.7-80.1 mg...

  3. 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., III; 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.

  4. A blood chemistry profile for lake trout

    Science.gov (United States)

    Edsall, Carol Cotant

    1999-01-01

    A blood chemistry profile for lake trout Salvelinus namaycush was developed by establishing baseline ranges for several clinical chemistry tests (glucose, total protein, amylase, alkaline phosphatase, alanine aminotransferase, aspartate aminotransferase, creatine kinase, calcium, and magnesium). Measurements were made accurately and rapidly with a Kodak Ektachem DT60 Analyzer and the Ektachem DTSC Module. Blood serum was collected from both laboratory-reared lake trout (1978 and 1986 year-classes) and feral spawning trout from Lake Michigan and then analyzed in the laboratory. No clinically significant differences were found between samples analyzed fresh and those frozen for 1 or 6 weeks. The ranges in chemistry variables for feral lake trout were generally wider than those for laboratory-reared lake trout, and significant differences existed between male and female feral lake trout for several tests. Blood chemistry profiles also varied seasonally on fish sampled repeatedly.

  5. Comparative Histomorphological Studies on Oesophagus of Catfish and Grass Carp

    Directory of Open Access Journals (Sweden)

    Enas A. Abd El Hafez

    2013-01-01

    Full Text Available The present work was carried out on 40 specimens of oesophaguses of both sexes of catfish (carnivorous fish and grass carp (herbivorous fish in order to observe the morphological and histological differences between the two species. Oesophagus of catfish was divided into 2 parts: anterior and posterior ones. The anterior part of the oesophagus of catfish was characterized by the presence of numerous mucosal folds. It was lined by stratified epithelium with goblet cells. In addition to club cells were observed in between the stratified epithelium. Scanning electron examination of the oesophageal epithelium of catfish demonstrated the presence of microvilli and fingerprint-like microridges in the superficial cell layer. The posterior part of the oesophagus of catfish was characterized by simple columnar mucus-secreting epithelium. The oesophagus of grass carp had shown the same structure along its entire length. It consisted of less folded mucosa than that observed in the oesophagus of catfish. The epithelium was characterized by the presence of taste buds. In conclusion, the present work revealed some differences in the structure of catfish oesophagus and grass carp oesophagus. These differences are related to type of food and feeding habits of each species.

  6. Geographical Distribution of Trout Farming in Turkey

    OpenAIRE

    Şahin, Güven; Erbilen, Süheyla Üçışık

    2011-01-01

    Turkey is a peninsula, surrounded by seas on three sides, with a total coastline of 8.333km. As a result of its heritage from ancient inland living culture, Turkey has a limited development in fishery production. However, there have been significant efforts in developing Trout Farming, compared to the other aquaculture products in Turkey. The recent developments in trout farming in Turkey have led to an increase in trout productions, providing alternatives for public nutrition. This study aim...

  7. GEOGRAPHICAL DISTRIBUTION OF TROUT FARMING IN TURKEY

    OpenAIRE

    Şahin, Güven; Erbilen, Süheyla Üçışık

    2011-01-01

    Turkey is a peninsula, surrounded by seas on three sides, with a total coastline of 8.333km. As a result of its heritage from ancient inland living culture, Turkey has a limited development in fishery production. However, there have been significant efforts in developing Trout Farming, compared to the other aquaculture products in Turkey. The recent developments in trout farming in Turkey have led to an increase in trout productions, providing alternatives for public nutrition. This study aim...

  8. Danish focus on organic trout fry

    OpenAIRE

    Jokumsen, Alfred

    2015-01-01

    RobustFish will strengthen the development of Danish organic trout production. According to the EU Regulation on Organic Aquaculture, the fish production shall exclusively be based on organic fry from 2016. Particularly, in organic farming, medication is only allowed within very strict limits. Therefore, the robustness of the fry to diseases is crucial. Especially, this concerns the most serious trout fry disease in Danish aquaculture, Rainbow Trout Fry Syndrome (RTFS). The robustness of the ...

  9. Boosting the quality of organic trout fry

    OpenAIRE

    Jokumsen, Alfred

    2015-01-01

    RobustFish will strengthen the development of Danish organic trout production. According to the EU Regulation on Organic Aquaculture, the fish production shall exclusively be based on organic fry from 2016. Particularly, in organic farming, medication is only allowed within very strict limits. Therefore, the robustness of the fry to diseases is crucial. Especially, this concerns the most serious trout fry disease in Danish aquaculture, Rainbow Trout Fry Syndrome (RTFS). The robustness of the ...

  10. The radiosensitivity of nile tilapia (Oreochromis niloticus) fingerlings

    International Nuclear Information System (INIS)

    The nile tilapia (Oreochromis niloticus), a very popular fish commercially in the Philippines, was studied to determine its radiosensitivity and to see its potential as a biological indicator in aquatic ecosystems. Nile tilapia was seen to be radiosensitive. The fish were exposed to gamma-irradiation and chromosomal aberrations were induced. The various types of aberrations seen were chromatid gaps, chromosome gaps, chromatid fragments, dicentric rings, fusions, despiralizations and translocations. Among the aberrations observed, dicentric rings, fusions and chromosome gaps were strongly correlated with dosage, with only the dicentric rings increasing steadily with increasing dosage. In the course of the study, the lethal dosage50 for nile tilapia with 18 days was determined and it was observed at 2.0 krad. The modal chromosome number was also established at 2n=44 with a karyotype exhibiting 22 pairs of acrocentric chromosomes with 2 pairs of marker chromosomes present. (Author)

  11. Identification of SNARE proteins in fish-Tilapia Oreochromis niloticus

    Institute of Scientific and Technical Information of China (English)

    HUANG Xiaohang; LAM Patrick P L; LIN Xuezheng; LIU Chenlin; BIAN Ji; GAISANO Herbert

    2007-01-01

    SNARE proteins are a group of membrane-associated proteins involved in exocytosis, secretion and membrane trafficking events in eukaryotic cells. Research on SNARE protein biology has become a more attractive field in recent years, which is applied to marine biology specifically to the fish Tilapia (Oreochromis niloticus). Plasma membrane fractions of different tissues of Tilapia, including brain, liver-pancreas, intestine, skin and muscle, were extracted, and immuno-decorated with isoform-specific antibodies to the SNARE families and associated proteins. The presence of Syntaxins -1A, 2 and 3, SNAP-23 and SNAP-25, VAMP-2, Munc-18-1 and Munc-13 in the brain was identified, which were differentially distributed in the other organ tissues of the fish Tilapia. The distinct distribution of SNARE and associated proteins will serve as the basis for further investigation into their special secretory function in these tissues of the fish.

  12. Complete mitochondrial DNA sequences of the Victoria tilapia (Oreochromis variabilis) and Redbelly Tilapia (Tilapia zilli): genome characterization and phylogeny analysis.

    Science.gov (United States)

    Kinaro, Zachary Omambia; Xue, Liangyi; Volatiana, Josies Ancella

    2016-07-01

    The Cichlid fishes have played an important role in evolutionary biology, population studies and aquaculture industry with East African species representing a model suited for studying adaptive radiation and speciation for cichlid genome projects in which closely related genomes are fast emerging presenting questions on phenotype-genotype relations. The complete mitochondrial genomes presented here are for two closely related but eco-morphologically distinct Lake Victoria basin cichlids, Oreochromis variabilis, an endangered native species and Tilapia zilli, an invasive species, both of which are important economic fishes in local areas. The complete mitochondrial genomes determined for O. variabilis and T. zilli are 16 626 and 16,619 bp, respectively. Both the mitogenomes contain 13 protein-coding genes, 22 tRNAs, 2 rRNAs and a non-coding control region, which are typical of vertebrate mitogenomes. Phylogenetic analyses of the two species revealed that though both lie within family Cichlidae, they are remotely related. PMID:27158785

  13. The Impact of Catfish Imports on the U.S. Wholesale and Farm Sectors

    OpenAIRE

    Muhammad, Andrew; Neal, Sammy J.; Hanson, Terrill R.; Jones, Keithly G.

    2010-01-01

    The primary objective of this study was to assess the impact of catfish imports and tariffs on the U.S. catfish industry, with particular focus on the U.S. International Trade Commission ruling on Vietnam in 2003. Given the importance of Vietnam to the U.S. catfish market, it was assumed that catfish import prices would increase by 35 percent if the maximum tariff was imposed on catfish from Vietnam. With the tariff, domestic catfish prices at the wholesale level would increase by $0.06 per l...

  14. Low-fat frankfurters from protein concentrates of tilapia viscera and mechanically separated tilapia meat.

    Science.gov (United States)

    Cavenaghi-Altemio, Angela D; Alcade, Lígia B; Fonseca, Gustavo G

    2013-11-01

    In order to develop a healthy low-fat frankfurter-type sausage, different formulations were developed with tilapia viscera surimi (T1) and two with mechanically separated tilapia meat (MSTM) surimi (T2 and T3), all without pig lard addition. Due to technological problems observed for T1 sausage during cooking, it was not further investigated. The functionality of the other two formulations was evaluated based on proximate composition, pH, water activity, and texture. Finally, microbiological and sensory analyses based on acceptance tests were performed. Listeria monocytogenes and Salmonella spp. were found to be absent. T2 showed higher frequencies for the attributes color (90.0%) and overall acceptability (86.7%), while T3 showed higher frequencies for taste (86.7%) and texture (96.7%). The surimi concentration was reflected in the physical properties of the sausages. It was found that the addition of MSTM surimi to sausage favored greater cutting strength (3.9 N for T2 and 4.9 N for T3). Beyond the surimi utilization, the total replacement of pig lard by cassava starch and soybean protein had also contributed with the texture properties. PMID:24804055

  15. Inapparent Streptococcus agalactiae infection in adult/commercial tilapia

    OpenAIRE

    Jiufeng Sun; Wei Fang; Bixia Ke; Dongmei He; Yuheng Liang; Dan Ning; Hailing Tan; Hualin Peng; Yunxin Wang; Yazhou Ma; Changwen Ke; Xiaoling Deng

    2016-01-01

    We report on inapparent infections in adult/commercial tilapia in major tilapia fish farms in Guangdong. A total of 146 suspected isolates were confirmed to be S. agalactiae using an API 20 Strep system and specific PCR amplification. All isolates were identified as serotype Ia using multiplex serotyping PCR. An MLST assay showed single alleles of adhP (10), atr (2), glcK (2), glnA (1), pheS (1), sdhA (3) and tkt (2), and this profile was designated ‘unique ST 7’. The analysis of virulence ge...

  16. Identification and Characterization of Full-Length cDNAs in Channel Catfish (Ictalurus punctatus) and Blue Catfish (Ictalurus furcatus)

    OpenAIRE

    Chen, Fei; Lee, Yoona; Jiang, Yanliang; Wang, Shaolin; Peatman, Eric; Abernathy, Jason; Liu, Hong; Liu, Shikai; Kucuktas, Huseyin; Ke, Caihuan; Liu, Zhanjiang

    2010-01-01

    Background Genome annotation projects, gene functional studies, and phylogenetic analyses for a given organism all greatly benefit from access to a validated full-length cDNA resource. While increasingly common in model species, full-length cDNA resources in aquaculture species are scarce. Methodology and Principal Findings Through in silico analysis of catfish (Ictalurus spp.) ESTs, a total of 10,037 channel catfish and 7,382 blue catfish cDNA clones were identified as potentially encoding f...

  17. Are brown trout replacing or displacing bull trout populations in a changing climate?

    Science.gov (United States)

    Al-Chokhachy, Robert K.; Schmetterling, David A.; Clancy, Chris; Saffel, Pat; Kovach, Ryan; Nyce, Leslie; Liermann, Brad; Fredenberg, Wade A.; Pierce, Ron

    2016-01-01

    Understanding how climate change may facilitate species turnover is an important step in identifying potential conservation strategies. We used data from 33 sites in western Montana to quantify climate associations with native bull trout (Salvelinus confluentus) and non-native brown trout (Salmo trutta) abundance and population growth rates (λ). We estimated λ using exponential growth state space models and delineated study sites based on bull trout use for either Spawning and Rearing (SR) or Foraging, Migrating, and Overwintering (FMO) habitat. Bull trout abundance was negatively associated with mean August stream temperatures within SR habitat (r = -0.75). Brown trout abundance was generally highest at temperatures between 12 and 14°C. We found bull trout λ were generally stable at sites with mean August temperature below 10°C but significantly decreasing, rare, or extirpated at 58% of the sites with temperatures exceeding 10°C. Brown trout λ were highest in SR and sites with temperatures exceeding 12°C. Declining bull trout λs at sites where brown trout were absent suggests brown trout are likely replacing bull trout in a warming climate.

  18. Use of similar habitat by cutthroat trout and brown trout in a regulated river during winter

    Science.gov (United States)

    Dare, M.R.; Hubert, W.A.

    2003-01-01

    Few differences in habitat use were observed between cutthroat trout and brown trout during winter in the Shoshone River, a regulated river in northwestern Wyoming. Radio-tagged fish of 20-30 cm total length were found in pool habitat five to six times more frequently than would be expected if they were using pools in proportion to pool availability. Nevertheless, run habitat was most frequently used by both species. The microhabitat characteristics at locations of each species were similar when in both pools and runs, however, habitat use was variable suggesting that a variety of microhabitats were suitable over-wintering habitat. Brown trout were more frequently associated with boulder cover than were cutthroat trout. Cutthroat trout used large pools that provided refuge from high water velocities more frequently that brown trout. Cutthroat trout and brown trout were found at similar distances from the bank except in late February when cutthroat trout were farther from the bank. Both species moved frequently during the winter, but cutthroat trout showed a greater propensity than brown trout to move long distances. This study suggests that during a mild winter in a stable environment, these species were able to overwinter successfully in a variety of habitats.

  19. The Effect of Addition Vitamin E on Catfish Oil Stability

    Directory of Open Access Journals (Sweden)

    Clara M. Kusharto

    2015-12-01

    Full Text Available Unsaturated fatty acids contained oils which sensitive to oxidation caused by heat, light and oxygen. The oxidized oil known harmful to the body. One of the effort to prevent the oxidation process is by adding antioxidants stability of oil catfish and shelf life of the oil. The experimental study was applied by adding vitamin E to the oil as much as 0.67 mg / g PUFA compared with the control oil. Oil was stored with the Schaal Oven Test method, which are stored at a temperature of 600C. The study showed that, based on the parameters of oxidation (free fatty acids, peroxide value, anisidin numbers, and the number of total oxidation, catfish oil were added vitamin E more stabilized than the catfish oil without added vitamin E. The catfish fish oil in the form of soft gell capsules added vitamin E could maintain stability in appropriate with IFOS up to 23 months.

  20. Physiology and immunology of mucosal barriers in catfish (Ictalurus spp.)

    Science.gov (United States)

    The mucosal barriers of catfish (Ictalurus spp.) constitute the first line of defense against pathogen invasion while simultaneously carrying out a diverse array of other critical physiological processes, including nutrient adsorption, osmoregulation, waste excretion, and environmental sensing. Catf...

  1. Isolation and characterization of Vibrio ( Listonella) anguillarum from catfish

    OpenAIRE

    Rad, Mehrnaz; Shahsavani, Davar

    2010-01-01

    Vibrio anguillarum was isolated from several organs of some aquarium catfish in a fish population with high mortality. Macroscopic examination of the affected catfish revealed ascites in the abdomen, site-petechiae, and dorsal erection. Although there are some variations in phenotypic characterization among different isolates of Vibrio anguillarum, the majority show a common biochemical profile with distinct microscopic appearance that can provide presumptive identification of Vibrio anguilla...

  2. Identification of Bacillus Strains for Biological Control of Catfish Pathogens

    OpenAIRE

    Ran, Chao; Carrias, Abel; Williams, Malachi A.; Capps, Nancy; Dan, Bui C. T.; Newton, Joseph C.; Joseph W Kloepper; Ooi, Ei L.; Browdy, Craig L.; Terhune, Jeffery S.; Liles, Mark R.

    2012-01-01

    Bacillus strains isolated from soil or channel catfish intestine were screened for their antagonism against Edwardsiella ictaluri and Aeromonas hydrophila, the causative agents of enteric septicemia of catfish (ESC) and motile aeromonad septicaemia (MAS), respectively. Twenty one strains were selected and their antagonistic activity against other aquatic pathogens was also tested. Each of the top 21 strains expressed antagonistic activity against multiple aquatic bacterial pathogens including...

  3. Xeroradiographic and radiographic anatomy of the channel catfish, Ictalurus punctatus

    International Nuclear Information System (INIS)

    The purpose of this study was to provide an anatomic reference for the channel catfish (Ictalurus punctatus) using xeroradiography† and conventional radiography. The entire body of three adult fish was radiographed using standard xeroradiographic and conventional radiographic techniques. Two xeroradiographs and their corresponding conventional radiographs were selected, and the xeroradiographs labeled to illustrate the normal skeletal and soft-tissue anatomy of the channel catfish

  4. Rainbow Trout Innate Immunity against Flavobacterium psychrophilum

    Science.gov (United States)

    Flavobacterium psychrophilum infection is associated with significant loss of rainbow trout production in the U.S. and other parts of the world. In 2005, a selective breeding program was initiated at the National Center for Cool and Cold Water Aquaculture to improve rainbow trout innate resistance ...

  5. 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...

  6. Masculinization of Nile tilapia (Oreochromis niloticus) by immersion in androgens

    Science.gov (United States)

    Gale, W.L.; Fitzpatrick, M.S.; Lucero, M.; Contreras-Sanchez, W.M.; Schreck, C. B.

    1999-01-01

    The use of all-male populations increases the efficiency and feasibility of tilapia aquaculture. The objective of this study was to determine the efficacy of a short-term immersion procedure for masculinizing Nile tilapia (Oreochromis niloticus). Two synthetic androgens were evaluated: 17α-methyldihydrotestosterone (MDHT) and 17α-methyltestosterone (MT). Exposure (3 h) on 10 and again on 13 days post-fertilization to MDHT at 500 μg/1 successfully masculinized fry in all experiments, resulting in 100, 94 and 83 ± 2% males in Experiments 1, 2 and 3, respectively. Immersions in MDHT or MT at 100 μg/1 resulted in significantly skewed sex ratios in Experiments 1 and 3 (MT resulted in 73 and 83 ± 3% males; and MDHT resulted in 72 and 91 ± 1% males) but not in Experiment 2. Immersion in MT at 500 μg/1 only caused masculinization in Experiment 3. Although further research and refinement is needed, immersion of Nile tilapia in MDHT may provide a practical alternative to the use of steroid-treated feed. Furthermore, when compared with current techniques for steroid-induced sex inversion of tilapia, short-term immersion reduces the period of time that workers are exposed to anabolic steroids.

  7. Human Streptococcus agalactiae Isolate in Nile Tilapia (Oreochromis niloticus)

    OpenAIRE

    Evans, Joyce J.; Klesius, Phillip H.; Pasnik, David J.; Bohnsack, John F.

    2009-01-01

    Streptococcus agalactiae, the Lancefield group B streptococcus (GBS) long recognized as a mammalian pathogen, is an emerging concern with regard to fish. We show that a GBS serotype Ia multilocus sequence type ST-7 isolate from a clinical case of human neonatal meningitis caused disease and death in Nile tilapia (Oreochromis niloticus).

  8. Use of coffee pulp as feed ingredient for tilapia culture

    NARCIS (Netherlands)

    Ulloa Rojas, J.B.

    2002-01-01

    This research focused on the feasibility of using coffee pulp (CoP) in diets for tilapia ( Oreochromis aureus ). First, a literature survey analyzed the limitations of CoP as an animal foodstuff (several antinutritional factors: ANF's, and high fibre contents), different ways to upgrade the CoP nutr

  9. Business plan Tilapia Pond Farming in the Zambezi Valley, Mozambique

    NARCIS (Netherlands)

    Meer, van der Magnus; Brouwer, J.H.

    2015-01-01

    This business plan has been prepared for local entrepreneurs who would like to expand their business portfolio or to start a value chain business in the aquaculture sector in the Zambezi Valley, Mozambique.

    Freshwater aquaculture in Mozambique consists mainly of small-scale tilapia producti

  10. Bath vaccination of rainbow trout against yersiniosis

    DEFF Research Database (Denmark)

    Raida, Martin Kristian; Buchmann, Kurt

    2007-01-01

    Studies have been conducted on the temperature-dependent effect of bath vaccination of rainbow trout against Yersinia ruckeri O1. Protection of rainbow trout fry against challenge, following bath vaccination with a bacterin of Yersinia ruckeri O1, the bacterial pathogen causing enteric red mouth...... 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......1 one and two month post vaccination at the three temperatures. Protection of vaccinated fish was seen one and two month post vaccination in rainbow trout reared at 15° C. There was no effect of vaccination in rainbow trout reared at 5 and 25° C. Spleen tissue was sampled from 5 vaccinated and 5...

  11. Exceptional cardiac anoxia tolerance in tilapia (Oreochromis hybrid).

    Science.gov (United States)

    Lague, Sabine L; Speers-Roesch, Ben; Richards, Jeffrey G; Farrell, Anthony P

    2012-04-15

    Anoxic survival requires the matching of cardiac ATP supply (i.e. maximum glycolytic potential, MGP) and demand (i.e. cardiac power output, PO). We examined the idea that the previously observed in vivo downregulation of cardiac function during exposure to severe hypoxia in tilapia (Oreochromis hybrid) represents a physiological strategy to reduce routine PO to within the heart's MGP. The MGP of the ectothermic vertebrate heart has previously been suggested to be ∼70 nmol ATP s(-1) g(-1), sustaining a PO of ∼0.7 mW g(-1) at 15°C. We developed an in situ perfused heart preparation for tilapia (Oreochromis hybrid) and characterized the routine and maximum cardiac performance under both normoxic (>20 kPa O(2)) and severely hypoxic perfusion conditions (tilapia heart maintained a routine normoxic cardiac output (Q) and PO under all hypoxic conditions, a result that contrasts with the hypoxic cardiac downregulation previously observed in vivo under less severe conditions. Thus, we conclude that the in vivo downregulation of routine cardiac performance in hypoxia is not needed in tilapia to balance cardiac energy supply and demand. Indeed, the MGP of the tilapia heart proved to be quite exceptional. Measurements of myocardial lactate efflux during severe hypoxia were used to calculate the MGP of the tilapia heart. The MGP was estimated to be 172 nmol ATP s(-1) g(-1) at 22°C, and allowed the heart to generate a PO(max) of at least ∼3.1 mW g(-1), which is only 30% lower than the PO(max) observed with normoxia. Even with this MGP, the additional challenge of acidosis during severe hypoxia decreased maximum ATP turnover rate and PO(max) by 30% compared with severe hypoxia alone, suggesting that there are probably direct effects of acidosis on cardiac contractility. We conclude that the high maximum glycolytic ATP turnover rate and levels of PO, which exceed those measured in other ectothermic vertebrate hearts, probably convey a previously unreported anoxia tolerance

  12. Viral encephalitis of tilapia larvae: primary characterization of a novel herpes-like virus.

    Science.gov (United States)

    Shlapobersky, Mark; Sinyakov, Michael S; Katzenellenbogen, Mark; Sarid, Ronit; Don, Jeremy; Avtalion, Ramy R

    2010-04-10

    We report here an outbreak of an acute disease that caused high mortality rate in laboratory-reared tilapia larvae. The disease was initially observed in inbred gynogenetic line of blue tilapia larvae (Oreochromis aureus) and could be transmitted to larvae of other tilapia species. Based on the clinical manifestation (a whirling syndrome), we refer to the disease as viral encephalitis of tilapia larvae. The disease-associated DNA virus is described and accordingly designated tilapia larvae encephalitis virus (TLEV). A primary morphological, biophysical and molecular characterization of TLEV is presented. By virtue of these properties, the newly discovered virus is a herpes-like virus. Phylogenetic analysis, albeit limited, confirms this assumption and places TLEV within the family of Herpesviridae and distantly from the families Alloherpesviridae and Iridoviridae. By using PCR with virus-specific primers, diseased larvae and adult TLEV carriers were also identified in tilapia delivered from external hatcheries. PMID:20117816

  13. Price Volatility Spillover in Agricultural Markets: An Examination of U.S. Catfish Markets

    OpenAIRE

    Buguk, Cumhur; Hudson, Darren; Hanson, Terrill R.

    2003-01-01

    Price volatility spillovers in the U.S. catfish supply chain are analyzed based on monthly price data from 1980 through 2000 for catfish feed, its ingredients, and farm- and wholesale-level catfish. The exponential generalized autoregressive conditional heteroskedasticity (EGARCH) model was used to test univariate volatility spillovers for prices in the supply chain. Strong price volatility spillover from feeding material (corn, soybeans, menhaden) to catfish feed and farm- and wholesale-leve...

  14. EFFECTS OF GENERIC ADVERTISING ON PERCEPTIONS AND BEHAVIOR: THE CASE OF CATFISH

    OpenAIRE

    Kinnucan, Henry W.; Venkateswaran, Meenakshi

    1990-01-01

    An eight equation partially-recursive econometric model is specified to indicate the effects of catfish advertising on product awareness, beliefs, attitude and consumption. Results indicate that the ad campaign in its first year (i) increased consumer's awareness on farm-raised catfish 15 percent, (ii) improved consumers' perceptions of and attitude toward catfish 3 to 6 percent, and (iii) increased at-home and restaurant purchases of catfish 12 to 13 percent. The response to the ad campaign ...

  15. Interactions Between Trout and Sculpin: Consequences of Trout Introductions for a Native Fish

    Science.gov (United States)

    Henry Zimmerman, J. K.; Vondracek, B.

    2005-05-01

    We examined interactions between a native (brook) and a nonnative (brown) trout with native slimy sculpin, to test whether introductions of a nonnative salmonid has an effect on growth and diet of sculpin where a native trout was present. Enclosures (1m2) were stocked with fish (five treatments: juvenile brown trout with sculpin, juvenile brook trout with sculpin, and single species controls) at three densities. Replicates of each treatment were placed in Valley Creek, MN, and fish growth rates were measured over six 38-day experiments, conducted over three years. We examined growth of each species in combined-species treatments versus growth of each species alone. We did not find evidence of competition between brook trout and sculpin, regardless of density or fish size. However, we observed competition between brown trout and sculpin, which depended on initial mass of each species. Sculpin gained greater mass when alone than with brown trout when sculpin size was large (>17g). Likewise, brown trout gained greater mass alone than with sculpin when brown trout size was large (>26g). We suggest that differences in morphology and foraging modes between the two native species allow them to coexist without competition, whereas nonnative brown trout compete with sculpin.

  16. Environmental color affects Nile tilapia reproduction

    Directory of Open Access Journals (Sweden)

    Volpato G.L.

    2004-01-01

    Full Text Available We investigated the effects of environmental color on the reproductive behavior of Nile tilapia, Oreochromis niloticus. Two environmental colors were tested by covering the aquarium (60 x 60 x 40 cm with white (12 groups or blue (13 groups cellophane and observing reproductive behavior in groups of 2 males (10.27 ± 0.45 cm and 3 females (10.78 ± 0.45 cm each. After assignment to the respective environmental color (similar luminosity = 100 to 120 Lux, the animals were observed until reproduction (identified by eggs in the female's mouth or up to 10 days after the first nest building. Photoperiod was from 6:00 h to 18:00 h every day. Food was offered in excess once a day and water quality was similar among aquaria. Daily observations were made at 8:00, 11:00, 14:00 and 17:00 h regarding: a latency to the first nest, b number of nests, c gravel weight removed (the male excavates the nest in the bottom of the aquarium, d nest area, and e mouthbrooding incubation (indication of reproduction. The proportion of reproducing fish was significantly higher (6 of 13 in the group exposed to the blue color compared the group exposed to the white color (1 of 12; Goodman's test of proportions. Moreover, males under blue light removed significantly larger masses of gravel (blue = 310.70 ± 343.50 g > white = 130.38 ± 102.70 g; P = 0.01 and constructed wider nests (blue = 207.93 ± 207.80 cm² > white = 97.68 ± 70.64 cm²; P = 0.03 than the control (white. The other parameters did not differ significantly between light conditions. We concluded that reproduction in the presence of blue light was more frequent and intense than in the presence of white light.

  17. Finding an adequate Tilapia feed for rural fish farmers in Mombasa.[Internship Report

    OpenAIRE

    Furrer, Thomas

    2011-01-01

    Seven different possible fish feeds for tilapia (a hybrid from Nile tilapia, Oreochromis niloticus crossed with Sabaki tilapia, Oreochromis spilurus) were carried out on an internship on Mtopanga farm at Bao-bab Trust, Bamburi. The ingredients tested should be easily available to local farmers in Mombasa and should take into account that valuable nutrients produced on a farm should not be fed to livestock as these are urgently needed in local communities. As a valuable animal protein which ca...

  18. Vegetable, livestock and agroindustrial products and byproducts: An alternative tilapia feeding

    OpenAIRE

    González Salas, R.; Romero Cruz, O.; Valdivié Navarro, M.; J. T. Ponce-Palafox

    2014-01-01

    In the culture of tilapia limited supply and high cost of fish meal have forced nutritionists to consider alternative sources of protein. Due to the importance of the products and by-products in fish feed, this paper aims to show the alternatives that have been used to partially or totally replace fish meal and soybean meal in tilapia growing. This paper showsthe maximum or optimal use of vegetable by-products for tilapia as cottonseed meal, sunflower, canola, soybean ...

  19. The biology, ecology, population parameters and the fishery of the Nile tilapia, Oreochromis niloticus (L)

    OpenAIRE

    Balirwa, J.S.

    1994-01-01

    Oreochromis niloticus (the Nile tilapia) and three other ti1apine species: Oreochromis leucostictus, Tilapia zi11ii and T. rendallii were introduced into Lakes Victoria, Kyoga and Nabugabo in 1950s and 1960s. The source and foci of the stockings are given by Welcomme (1966) but the origin of the stocked species was Lake Albert. The Nile tilapia was introduced as a management measure to relieve fishing pressure on the endemic tiapiines and, since it grows to a bigger size, to...

  20. Non-infectivity of Cattle Streptococcus agalactiae in Nile Tilapia, Oreochromis niloticus and Channel Catfish, Ictalurus punctatus

    Science.gov (United States)

    Streptococcus agalactiae is classified as a Lancefield’s group B Streptococcus (GBS). It is the causative bacterium of streptococcosis that is responsible for severe economic losses in wild and cultured fish, worldwide. Streptococcus agalactiae also causes bovine mastitis. Only limited comparativ...

  1. 40 CFR 408.10 - Applicability; description of the farm-raised catfish processing subcategory.

    Science.gov (United States)

    2010-07-01

    ...-raised catfish processing subcategory. 408.10 Section 408.10 Protection of Environment ENVIRONMENTAL... SOURCE CATEGORY Farm-Raised Catfish Processing Subcategory § 408.10 Applicability; description of the farm-raised catfish processing subcategory. The provisions of this subpart are applicable to...

  2. Hydrogen peroxide treatments for channel catfish eggs infected with water molds

    Science.gov (United States)

    Fungi, or water molds Saprolegnia spp., on channel catfish Ictalurus punctatus eggs can lower fry production. This requires the producer to spawn more catfish or face fingerling shortages. Few treatments have been tested against channel catfish eggs infested with an identified fungus. Hydrogen pe...

  3. Proximate Composition and Collagen Concentration of Processing Residue of Channel Catfish

    Science.gov (United States)

    Residues (including heads, skin, viscera, frames, and trimmings) from the channel catfish Ictalurus punctatus processing industry have generally been made into catfish meal and catfish oil that are used in animal feeds. There may be more efficient uses for these materials, such as producing collagen...

  4. Breeding strategy of US farm-raised channel catfish, Ictalurus punctatus affects progeny production and performance

    Science.gov (United States)

    catfish propagation for decades has been dependent on random mating of male and female channel catfish in ponds. It is simple and has been fairly successful in fulfilling the needs of the US farm-raised catfish industry. However, natural pond spawning is unreliable, unpredictable, and incurs 30 t...

  5. SNP discovery and validation in wild and domesticated populations of blue catfish, Ictalurus furcatus, using genotyping-by-sequencing (GBS)

    Science.gov (United States)

    Blue catfish, Ictalurusfurcatus, are valued in the United States as a trophy fishery for their capacity to reach large sizes, sometimes exceeding 45 kg. Additionally blue catfish x channel catfish (I. punctatus) hybrid food fish production has recently increased the demand for blue catfish broodsto...

  6. Molecular characterization and functional analysis of IRF3 in tilapia (Oreochromis niloticus).

    Science.gov (United States)

    Gu, Yi-Feng; Wei, Qun; Tang, Shou-Jie; Chen, Xiao-Wu; Zhao, Jin-Liang

    2016-02-01

    Interferon regulatory factor 3 (IRF3) plays a key role in interferon (IFN) response and binding to the IFN stimulatory response elements (ISREs) within the promoter of IFN and IFN-stimulated genes followed by virus infection. In the current study, we discovered one IRF3 homologue in tilapia genome and analyzed the characterizations and functions of tilapia IRF3. Tilapia IRF3 contains 1368 bp with an ORF of 455 aa. Structurally, tilapia IRF3 protein typically shares the conserved characterizations with other species' IRF3 homologues, displaying conserved DNA-binding domain, IRF association domain, serine-rich C terminal domain, and tryptophan residue cluster. Phylogenetic analysis illustrated that tilapia IRF3 belongs to the IRF3 subfamily. Real-time PCR revealed a broad expression pattern of tilapia IRF3 in various tissues. Subcellular localization analysis showed that tilapia IRF3 mainly resides in the cytoplasm, Western blot demonstrated that IRF3 was distributed in the cytoplasmic fraction. Functionally, IRF3 was found to be transcriptionally up-regulated by the poly I:C stimulation. Moreover, reporter assay elucidated that tilapia IRF3 serves as a regulator in mediating IFN response by increasing the activity of IFN-β and ISRE-containing promoter. These data supported the view that tilapia IRF3 is a potential molecule in IFN immune defense system against viral infection. PMID:26483348

  7. The Use of Random Amplified Polymorphic DNA (RAPD) Markers in Sex Discrimination in Nile Tilapia, Oreochromis niloticus (Pisces: Cichlidae)

    OpenAIRE

    Bardakci, Fevzi

    2000-01-01

    Random amplified polymorphic DNA (RAPD) markers were successfully used in discrimination of sexes in Nile tilapia fish ( Oreochromis niloticus) using linear discriminant function analysis. The results provide support for the view that major genetical sex determining factors exist in tilapia.

  8. Pyrethroid toxicity in silver catfish, Rhamdia quelen

    Directory of Open Access Journals (Sweden)

    Francisco P. Montanha

    2012-12-01

    Full Text Available This study aimed to determine both the lethal and sublethal concentrations of Cypermethrin in young Silver Catfish (Brazilian "Jundiá", Rhamdia quelen on aquatic environment during 96 hours, as well as to determine the Cypermethrin and Deltamethrin sublethal concentrations during the initial embryonic development period of Rhamdia quelen, and to verify their respective rates of fertilization, hatching and survival. Pyrethroid nowadays is a widely used insecticide, which presents a high toxicity to fish. In order to determine lethal and sublethal concentrations, 120 silver catfish were used; each one had an average weight of 59.58±4.50g and an average size of 20.33±2.34cm. Concentrations used were 0, 1.0, 1.5, 2.0, 2.5, 3.0, 5.0, 10.0, 15.0 and 20.0mg of Cypermethrin per liter of water (mg/L. Fish were exposed to the product in 30-liter fish tanks. In each fish tank there were four fishes and the product was applied three times, i.e., a total of twelve fish were exposed to the product at each application, and a total of 120 fish during the entire experiment (n=120. In order to determine the Cypermethrin and Deltamethrin sublethal concentrations during the initial embryonic development, ovulation induction was performed on female fishes using hormones, and then and egg collection was performed. The eggs were then hydrated and fertilized in Cypermethrin and Deltamethrin in different concentrations: 0.001, 0.01, 0.1, 1.0 and 10.0mg/L of Cypermethrin and 0.001, 0.01, 0.1, 0.5 and 1.0mg/L of Deltamethrin, in addition to the control group (0mg/L. After fertilization, the eggs were kept in containers with the respective pesticides of Cypermethrin and Deltamethrin until hatching, when hatching rate was verified. Then the alevins, from the hatching, were kept on their respective concentrations of Cypermethrin and Deltamethrin so that the survival rate could be analyzed regarding the tested insecticides, during both 12-hour and 24-hour periods

  9. Patterns of hybridization among cutthroat trout and rainbow trout in northern Rocky Mountain streams

    OpenAIRE

    McKelvey, Kevin S.; Young, Michael K.; Taylor M Wilcox; Bingham, Daniel M.; Pilgrim, Kristine L.; Schwartz, Michael K.

    2016-01-01

    Abstract Introgressive hybridization between native and introduced species is a growing conservation concern. For native cutthroat trout and introduced rainbow trout in western North America, this process is thought to lead to the formation of hybrid swarms and the loss of monophyletic evolutionary lineages. Previous studies of this phenomenon, however, indicated that hybrid swarms were rare except when native and introduced forms of cutthroat trout co‐occurred. We used a panel of 86 diagnost...

  10. EVALUATION OF THE POSSIBLE THREAT OF NAFTA ON U.S. CATFISH INDUSTRY USING A TRADITIONAL IMPORT DEMAND FUNCTION

    OpenAIRE

    Ligeon, Carel; Jolly, Curtis M.; John D. Jackson

    1996-01-01

    The effects of increased exports from NAFTA member countries on the U.S. domestic catfish industry were evaluated. Results showed that the quantity of catfish imported will fall if the domestic price of catfish falls relative to the import price. Past imports have no effect on present imports. The income elasticity was negative indicating that imported catfish may be an inferior good. Doubling present levels of imports from NAFTA member countries is not a threat to the U.S. catfish industry.

  11. ANALYSIS OF FACTORS INFLUENCING THE FREQUENCY OF CATFISH CONSUMPTION IN THE UNITED STATES

    OpenAIRE

    Drammeh, Lamin; House, Lisa; Sureshwaran, Suresh; Selassie, Haile

    2002-01-01

    Consumption of seafood, including catfish, has become an important part of the diet for consumers in the United States. Per capita consumption of catfish increased from 0.41 pounds in 1985 to 0.90 pounds in 2001. The goal of this study is to investigate factors that influence the decisions to consume and frequency of consumption of catfish. One finding was the main emphasis of the Catfish Institute to market catfish as "farm-raised" and to increase preparation knowledge through distribution o...

  12. 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...

  13. Effectiveness of Aquaflor (50% florfenicol) administered in feed to control mortality associated with Streptococcus iniae in tilapia at a commercial tilapia production facility

    Science.gov (United States)

    Gaikowski, Mark P.; Schleis, Susan M.; Leis, Eric; Lasee, Becky A.; Endris, Richard G.

    2014-01-01

    The efficacy of Aquaflor (florfenicol; FFC) to control mortality caused by Streptococcus iniae in tilapia was evaluated under field conditions. The trial was initiated following presumptive diagnosis of S. iniae infection in a mixed group of fingerling (mean, 4.5 g) Nile Tilapia Oreochromis niloticus and a hybrid of Nile Tilapia×Blue Tilapia O. aureus. Diagnoses included mortality in source tank; examination of clinical signs and presence or absence of gram-positive cocci in brain, and collection of samples for microbiological review and disease confirmation of 60 moribund fish. Following presumptive diagnosis, tilapia (83/tank) were randomly transferred to each of 20 test tanks receiving the same water as the source tank (test tank water was not reused). Tilapia were offered either nonmedicated control feed or FFC-medicated feed (FFC at 15 mg/kg body weight/d; 10 tanks per regimen) for 10 consecutive days followed by a 14-d observation period during which only the nonmedicated control feed was offered. Streptococcus iniae was presumptively identified during pretreatment necropsy and confirmed by polymerase chain reaction assay; S. iniae was confirmed in samples taken during the dosing period but was not detected during the postdosing period. The FFC disk diffusion zone of inhibition ranged from 29 to 32 mm, while the minimum inhibitory concentration of FFC ranged from 2 to 4 μg/mL for the S. iniae isolates collected. Survival of tilapia assigned to the FFC-dose group was significantly greater at 14 d posttreatment than that of the nonmedicated controls. The odds of tilapia assigned to the FFC-dose group surviving to the end of the postdosing period were 1.34 times the odds of survival of tilapia assigned to the nonmedicated control group. There were no clinically apparent adverse effects associated with the administration of FFC-medicated feed in this study.

  14. Book review: Conservation, ecology, and management of catfish: The second international symposium

    Science.gov (United States)

    Long, James M.

    2013-01-01

    This is the second publication in a series published by the American Fisheries Society devoted to catfish research, biology, and management, which was organized as a symposium held in St. Louis Missouri, in 2010 and builds upon the first symposium that was held in Davenport, Iowa, in 1998 (Irwin et al. 1999).  The organizations of the second symposium stated that this was to "serve as an addendum to Catfish 2000" and "to cover the four corners of catfish science: catfish biology, ecology, management, and conservation" (p. xi).  The book meets this standard easily.  With 64 pages organized into nine sections (plenary, catfishes as sport fish, non-game catfishes, nonnative catfishes, movement and habitat use, sampling and population assessment, age and growth, behavior, and future directions), this publication covers these four corners and more.

  15. Partial sodium replacement in tilapia steak without loss of acceptability.

    Science.gov (United States)

    Monteiro, Maria Lúcia G; Mársico, Eliane T; Canto, Anna Carolina V C S; Costa-Lima, Bruno R C; Lázaro, César A; Cruz, Adriano G; Conte-Júnior, Carlos A

    2015-06-01

    The aim of this study was to evaluate physical and sensory characteristics of low-sodium tilapia steaks restructured with microbial transglutaminase. Polyphosphate (0.4%), condiment mixes-onion powder and garlic powder (2.5%), water (10.0%), transglutaminase (1.0%), and different types of salts (1.5%) were mixed with non-commercial sized fillets. Substitution of NaCl by KCl or MgCl2 (at 50% each) affected quality attributes and decreased (P purchase intention. We conclude that potassium and magnesium chlorides are possible replacers of salt (NaCl) in restructured tilapia steaks and potentially decrease the risk factor for heart failure associated with high sodium consumption. PMID:24831644

  16. Megalocytivirus infection in cultured Nile tilapia Oreochromis niloticus.

    Science.gov (United States)

    Subramaniam, Kuttichantran; Gotesman, Michael; Smith, Charlie E; Steckler, Natalie K; Kelley, Karen L; Groff, Joseph M; Waltzek, Thomas B

    2016-05-26

    Megalocytiviruses, such as infectious spleen and kidney necrosis virus (ISKNV), induce lethal systemic diseases in both ornamental and food fish species. In this study, we investigated an epizootic affecting Nile tilapia Oreochromis niloticus cultured in the US Midwest. Diseased fish displayed lethargy, gill pallor, and distension of the coelomic cavity due to ascites. Histopathological examination revealed a severe systemic abundance of intravascular megalocytes that were especially prominent in the gills, kidney, spleen, liver, and intestinal submucosa. Transmission electron microscopic examination revealed abundant intracytoplasmic polygonal virions consistent with iridovirus infection. Comparison of the full-length major capsid protein nucleotide sequences from a recent outbreak with a remarkably similar case that occurred at the same facility many years earlier revealed that both epizootics were caused by ISKNV. A comparison of this case with previous reports suggests that ISKNV may represent a greater threat to tilapia aquaculture than previously realized. PMID:27225209

  17. Hydrography - Class A Wild Trout Streams - points

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — Class A streams are streams that support a population of wild (natural reproduction) trout of sufficient size and abundance to support a long-term and rewarding...

  18. Hydrography - Class A Wild Trout Streams

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — Class A streams are streams that support a population of wild (natural reproduction) trout of sufficient size and abundance to support a long-term and rewarding...

  19. Longevity of Lake Superior lake trout

    Science.gov (United States)

    Schram, Stephen T.; Fabrizio, Mary C.

    1998-01-01

    The age structure of mature lake trout Salvelinus namaycush from the Wisconsin waters of Lake Superior increased following a population recovery that has taken place since the 1960s. As the population aged, it became apparent that scales were unreliable aging structures. Beginning in 1986, we examined both scale and sagittal otolith ages from tagged fish with a known period at liberty. We found large discrepancies in scale and sagittal otolith ages of mature fish, such that scale ages were biased low. We estimated lake trout living up to 42 years, which is greater than previously reported from Lake Superior. Investigators studying lake trout population dynamics in the Great Lakes should be aware that lake trout can live longer than previously thought.

  20. A Vegetation Survey of Trout Brook Flowage

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The Trout Brook structure was started in 1963 under the Accelerated Public Works Program and finished in the summer of 1965. There is a 200 foot earthdike, a metal...

  1. Effect of feeding supplementary diets containing soybeans and moringa leaves on growth and fillet quality of Nile tilapia (Oreochromis niloticus), and comparison of growth and fillet quality between Nile tilapia (O. niloticus) and Wami River tilapia (O. urolepis hornorum)

    OpenAIRE

    Lemmens, Sebastiaan Cornelis Abraham

    2014-01-01

    The primary object of this study is to compare effects of various diets and tilapia species on growth performance and fillet quality. The secondary objective is to evaluate which diet could serve as a good alternative for usage in Tanzania´ backyard farming and perhaps in the planned breeding program of GIFT tilapia at Sokoine University of Agriculture (SUA). The trial underlying this report was performed at SUA in Morogoro, Tanzania, comprising two experiments. Both experiments were imple...

  2. Tilapia rendalli increases phytoplankton biomass of a shallow tropical lake

    OpenAIRE

    Lúcia Helena Sampaio da Silva; Marlene Sofia Arcifa; Gian Salazar-Torres; Vera Lúcia de Moraes Huszar

    2014-01-01

    AIM: This study aimed to experimentally test the influence of a planktivorous filter-feeding fish (Tilapia rendalli) on the phytoplankton dynamics of a small and shallow tropical reservoir (Lake Monte Alegre, Brazil). Adults of T. rendalli of this lake feed preferentially on phytoplankton, and we hypothesize that: I) adults of T. rendalli will decrease the phytoplankton biomass and composition through direct herbivory, and II) as it is a eutrophic system, fish would not have strong influence ...

  3. Mathematical modeling for digestible protein in animal feeds for tilapia

    OpenAIRE

    Luiz Vítor Oliveira Vidal; Wilson Massamitu Furuya; Elias Nunes Martins; Tadeu Orlandi Xavier; Mariana Michelato; Themis Sakaguti Graciano

    2012-01-01

    The objective of this study was to formulate mathematical models to estimate digestible protein in some animal feeds for tilapia. Literature results of the proximate composition of crude protein, ether extract, and mineral matter, as well as digestible protein obtained in biological assays, were used. The data were subjected to multiple linear stepwise backward regression. Path analysis was performed to measure the direct and indirect effects of each independent variable on the dependent one....

  4. Use of coffee pulp as feed ingredient for tilapia culture

    OpenAIRE

    Ulloa Rojas, J.B.

    2002-01-01

    This research focused on the feasibility of using coffee pulp (CoP) in diets for tilapia ( Oreochromis aureus ). First, a literature survey analyzed the limitations of CoP as an animal foodstuff (several antinutritional factors: ANF's, and high fibre contents), different ways to upgrade the CoP nutritional value and the maximal inclusion level of CoP in diets for ruminants, monogastric animals and fish ( Chapter 1 ).Next, an inventory of agricultural activities in the country (Costa Rica) was...

  5. Production and utilization of tilapia feed in Rural Zambia

    OpenAIRE

    Hänninen, Antti

    2014-01-01

    The overall objective of the study was to promote aquaculture development in Luapula Province, in Zambia, by carrying out research activities regarding tilapia feeding in semi-intensive culture (SIC). The field work was conducted in the province in two periods (2013 and 2014). The research included mainly identification of locally available feed materials, development of performing feeding regime, nutrient-rich and affordable feed formulae and implementation of trials to assess feed performan...

  6. Particle size distribution in the tilapia Recirculating Aquaculture System

    OpenAIRE

    Stokic, Jelena

    2012-01-01

    This study was to evaluate methods for measuring and describing particle size distribution from three different spots in Tilapia recirculating system at University of Life Ccience in Ås, Norway. For this purpose serial filtration over different mesh size and parallel filtration over different mesh size methods were compared. Water samples were taken from before drum filter, after drum filter and after bio-filter (MBBR) and filtrated through eight different mesh size classes and calculated in ...

  7. 17a-Methyltestosterone - Medicated feed administered to Tilapia: Survival and pathologies.

    Science.gov (United States)

    17a-Methyltestosterone (17MT) is used in U.S. aquaculture under an Investigational New Animal Drug exemption to produce male populations of tilapia. Efforts to gain FDA-approval include this Target Animal Safety study. A study was designed to determine its histological safety to tilapia when fed a...

  8. Complete Genome Sequence of Streptococcus agalactiae Strain S25 Isolated from Peritoneal Liquid of Nile Tilapia.

    Science.gov (United States)

    Mainardi, Rafaella Menegheti; Lima Júnior, Edson Antônio; Ribeiro Júnior, Jose Carlos; Beloti, Vanerli; Carmo, Anderson Oliveira; Kalapothakis, Evanguedes; Gonçalves, Daniela Dib; Padua, Santiago Benites; Pereira, Ulisses Pádua

    2016-01-01

    Streptococcus agalactiae (Lancefield group B; GBS) is one of the major pathogens in fish production, especially in Nile tilapia (Oreochromis niloticus). The genomic characteristics of GBS isolated from fish must be more explored. Thus, we present here the genome of GBS S25, isolated from Nile tilapia from Brazil. PMID:27491974

  9. Risks for fishborne zoonotic trematodes in tilapia production systems in Guangdong province, China

    DEFF Research Database (Denmark)

    Li, Kang; Clausen, Jesper Hedegaard; Murrell, Kenneth Darwin;

    2013-01-01

    Guangdong province is the most important region for tilapia culture in China. However, it is also an endemic region for fishborne zoonotic trematodes (FZT), which pose a risk to human food safety and health. A study was designed to assess the status of trematode parasite infections in tilapia...

  10. Dietary supplementation with arachidonic acid in tilapia (Oreochromis mossambicus) reveals physiological effects not mediated by prostaglandins.

    NARCIS (Netherlands)

    Anholt, R.D. van; Spanings, F.A.T.; Koven, W.M.; Wendelaar Bonga, S.E.

    2004-01-01

    This study aims to clarify the role of the polyunsaturated fatty acid arachidonic acid (ArA, 20:4n-6) in the stress response of Mozambique tilapia (Oreochromis mossambicus). ArA is converted into eicosanoids, including prostaglandins, which can influence the response to stressors. Tilapia, a species

  11. Susceptibility of Nile tilapia (Oreochromis niloticus) fed dietary sodium chloride to nitrite toxicity

    Science.gov (United States)

    Juvenile Nile tilapia (Oreochromis niloticus) were fed diets supplemented with 0 or 6% NaCl for 10 weeks. Tilapia were exposed to approximately 21 mg/l nitrite-N after five and ten weeks of feeding to determine the effect of dietary NaCl supplementation on resistance to nitrite toxicity. Fish were...

  12. Laboratory efficacy of oxytetracyline and amoxicillin for the control of Streptococcus iniae infection in tilapia

    Science.gov (United States)

    Streptococcus iniae infection of tilapia is common in different parts of the world including the United States. The infection has caused devastating economic losses and the closure of many tilapia operations. Proper husbandry and health management practices are essential but when a virulent outbre...

  13. Controlled laboratory challenge demonstrates substantial additive genetic variation in resistance to Streptococcus iniae in Nile tilapia

    Science.gov (United States)

    Streptococcus iniae is an etiologic agent of streptococcal disease in tilapia and is one of several Streptococcus spp. that negatively impact worldwide tilapia production. Methods for the prevention and control of S. iniae include vaccines, management strategies, and antibiotics. An alternative and ...

  14. Efficacy of an experimentally inactivated Streptococcus agalactiae vaccine in Nile tilapia (Oreochromis niloticus) reared in Brazil

    Science.gov (United States)

    Tilapia aquaculture is one of the fastest growing segments of fish production in Brazil. Nile tilapia (Oreochromis niloticus) is largely cultivated in the state of Parana, where Streptococcus agalactiae is the cause of severe disease outbreaks. The objective of this paper was to evaluate an inactiva...

  15. Spawning Behaviour and the Softmouth Trout Dilemma

    OpenAIRE

    Esteve Manu; McLennan Deborah Ann; Zablocki John Andrew; Pustovrh Gašper; Doadrio Ignacio

    2014-01-01

    Morphological, ecological and molecular data sets do not completely agree on the phylogenetic placement of the softmouth trout, Salmo (Salmothymus) obtusirostris (Heckel). Molecules posit that softmouths are closely related to brown trout, Salmo trutta L. while some morphological, ecological and life history traits place them in the most basal position of the Salmoninae subfamily between grayling (Thymallus) and lenok (Brachymystax). Here we add an additional source of data, behavioural chara...

  16. The Characterization of Fish (Tilapia Collagen Sponge as a Biomaterial

    Directory of Open Access Journals (Sweden)

    Kohei Yamamoto

    2015-01-01

    Full Text Available For scaffold manufacturing, the utility of bioactive natural organic materials derived from marine products is useful and indispensable as an alternative to bovine collagen. The weakest feature of fish collagen for scaffold application is its low degeneration temperature (Td, indicating poor stability of fish collagen in mammals in vivo. We have focused on the tropical fish tilapia as a candidate for generating a clinical scaffold. The aim of this study was to confirm the Td of tilapia type I atelocollagen (TAC for biomedical application. Furthermore, the physical and structural properties were investigated and evaluated as a scaffold on a sponge form. Different concentrations {0.5%, 1.0%, and 2.0% (v/v} of TAC solution were analyzed. Differential scanning calorimetry showed that the Td of TAC was 35-36°C. The scanning electron microscopy results indicated that the pore size (90–160 μm of TAC sponges is acceptable for cell proliferation. The tensile strength of porous sponges was in the range of 0.01–0.07 MPa. These findings indicate that the TAC sponge prepared from tilapia is one of candidates as a scaffold. The 1.0% (v/v concentration of TAC solution is especially recommended to be advantageous for preparing and handling the solution and for sponge formation.

  17. Screening and identification of a microsatellite marker associated with sex in Wami tilapia, Oreochromis urolepis hornorum

    Indian Academy of Sciences (India)

    HUAPING ZHU; ZHIGANG LIU; MAIXIN LU; FENGYING GAO; XIAOLI KE; DONGMEI MA; ZHANGHAN HUANG; IANMENG CAO; MIAO WANG

    2016-06-01

    In this study, primer pairs of 15 microsatellite markers associated with sex determination of tilapia were selected and amplified in Wami tilapia, Oreochromis urolepis hornorum. While one marker, UNH168, on linkage group 3 (LG3) was associated((P<0.001) with the phenotypic sex in the experimental population, nine genotypes were detected in both sexes. Only 99-bp allele was detected in the female samples, while 141, 149 and 157-bp alleles were present in both male and female samples. UNH168 was localized by fluorescence in situ hybridization (FISH) on the long arm of the largest tilapia chromosome pair (chromosome 1, equivalent to LG3). This sex-linked microsatellite marker could potentially be used for marker-assisted selection in tilapia breeding programmes to produce monosex male tilapia

  18. Experiments to determine the tebuconazole doses (folicur 200 ce on the behaviour of tilapia (tilapia rendalli and pacu (piractus mesopotamicus

    Directory of Open Access Journals (Sweden)

    Mário Rodrigues Peres

    Full Text Available Some of the agricultural practices are given water qualitative risks especially by the use of agrochemicals can cause health and environmental damage. This trial had as an objective to determine the influence of tebuconazole doses on the behaviour of Tilapia rendalli and Piaractus mesopotamicus. The trial was carried out at fish laboratory on march, 2002 at Centro Regional Universitário de Espírito Santo do Pinhal – CREUPI at São Paulo state, Brazil. The treatments tested were different doses of tebuconazole fungicide, that is very used on coffee crop in order to control plant diseases. The results showed difference among tebuconazole doses on the behavior of Tilapia rendalli and Piaractus mesopotamicus, except at 1,94 ppm concentration when both were resistant.

  19. 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.

  20. Does the introduced brook trout ( Salvelinus fontinalis) affect growth of the native brown trout ( Salmo trutta)?

    Science.gov (United States)

    Korsu, Kai; Huusko, Ari; Muotka, Timo

    2009-03-01

    Non-native brook trout have become widely established in North European streams. We combined evidence from an artificial-stream experiment and drainage-scale field surveys to examine whether brook trout suppressed the growth of the native brown trout (age 0 to age 2). Our experimental results demonstrated that brown trout were unaffected by the presence of brook trout but that brook trout showed reduced growth in the presence of brown trout. However, the growth reduction only appeared in the experimental setting, indicating that the reduced spatial constraint of the experimental system may have forced the fish to unnaturally intense interactions. Indeed, in the field, no effect of either species on the growth of the putative competitor was detected. These results caution against uncritical acceptance of findings from small-scale experiments because they rarely scale up to more complex field situations. This and earlier work suggest that the establishment of brook trout in North European streams has taken place mainly because of the availability of unoccupied (or underutilized) niche space, rather than as a result of species trait combinations or interspecific competition per se.

  1. 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.

  2. 黄颡鱼HSC70基因及其组织表达分析%HSC70 GENE AND ITS TISSUE EXPRESSION ANALYSIS IN YELLOW CATFISH

    Institute of Scientific and Technical Information of China (English)

    张娟; 张其中; 张占会; 崔淼

    2009-01-01

    ' untranslated region of 82 bp and 3' untranslated region of 225 bp. The deduced 645 amino acid sequence contained HSP70s' characteristic motifs (Fig. 2), and it indicated that the cDNA belonged to the family of heat shock protein 70. Carried out alignment with other organ-isms' HSC70 amino acid sequences, the deduced amino acid sequence from the eDNA showed the highest similarity (96.13 % ) with HSC70 amino acid sequence of Southern catfish (Silurus meridionalis). The phylogenetic tree ( Fig. 3) showed that 70 kD heat shock protein of yellow catfish clustered together with other vertebrates' HSC70s but not HSP7Os. What mentioned above suggested that the sequence we cloned was a kind of heat shock cognate 70 (HSC70). Further-more, its constitutive expression in unstressed tissue cells by RT-PCR detection (Fig. 4) confirmed that the sequence we cloned was HSC70 eDNA. Subsequently, the catfish HSC70 gene was cloned by PCR amplification in the fish genome DNA. Eight introns were found in the HSCIO gene, and the longest intron (873bp) was located in 5' untranslated region and the others (length between 80 and 251 bp) in ORF region (Fig. 2). The introns with same number and similar loca- tion were found in the HSC70 genes of human ( Homo sapiens), mouse ( Mus musculus) , rainbow trout ( Oncorhynchus mykiss) and hermaphroditic teleost ( Rivulus marmoratus). In order to elucidate the HSC70 mRNA expression in different tissues or organs of yellow catfish under heat-treated or unstressed condition, ten catfish were divided into two groups randomly, one (control group) was unstressed and the cat- fish were cultured in water temperature of (26 + 1 ) °C, the other ( the heat shock group) was heat-treated at (36 + 1 ) °C for 1 h, and then recovered in normal water temperature (26 + 1 ) C for 3h. Semi-quantitative RT-PCR method was em-ployed to analyze the HSC70 mRNA expression in different tissues or organs, viz. , blood cell, heart, liver, head kidney, spleen, gill, muscle and brain. The

  3. Bull Trout Spawning Surveys: Kootenai National Wildlife Refuge

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Bull trout are listed as threatened under the Endangered Species Act and Myrtle Creek was designated as critical habitat for bull trout this year. Myrtle Creek...

  4. Genetic structure and gene flow in an endangered native tilapia fish (Oreochromis esculentus) compared to invasive Nile tilapia (Oreochromis niloticus) in Yala swamp, East Africa

    OpenAIRE

    Angienda, Paul O.; Lee, Hyuk Je; Elmer, Kathryn R.; Abila, Romulus; Waindi, Eliud N.; Meyer, Axel

    2010-01-01

    The introduction of invasive Nile tilapia (Oreochromis niloticus), and the rapacious predator Nile perch (Lates niloticus), into Lake Victoria resulted in a decline in population sizes, genetic diversity and even extirpation of native species which were previously the mainstay of local fisheries. However, remnant populations of native fish species, including tilapia, still persist in satellite lakes around Lake Victoria where they may coexist with O. niloticus. In this study we assessed popul...

  5. Important Considerations for Methemoglobin Measurement in Fish Blood: Assay Choice and Storage Conditions

    Energy Technology Data Exchange (ETDEWEB)

    Kuntz, Mel Anton; Rodnick, K. J.; J. A. Lacey

    2002-05-01

    Spectrophotometric assays of methaemoglobin (metHb) in rainbow trout Oncorhynchus mykiss, channel catfish Ictalurus punctatus, tilapias Tilapia niloticus and Tilapia zillii and white sturgeon Acipenser transmontanus, under baseline conditions, were low (<4%) for each species, and yet higher than human values (<1%). MetHb results for a given fish species varied significantly between assays and two assays were deemed unacceptable for particular animals. For rainbow trout, white sturgeon, and the two species of tilapia, the Dubowski method gave uncharacteristically high estimates of metHb. MetHb could not measured in tilapia blood using the Evelyn & Malloy method due to spectral interference. Only the Horecker & Brackett assay worked well for all species. Storage conditions were extremely important in the quantification of metHb in rainbow trout blood. For consistent values, samples can be stored up to 4 h on ice (0 degrees C) or at least 20 days under liquid nitrogen (-196 degrees C). Auto-oxidation, however, elevates rainbow trout metHb at -20 and -80 degrees C. It should not be assumed that the blood of fishes and humans perform similarly during assays of metHb.

  6. Survival of Trout Strains as Affected by Limnological Parameters

    OpenAIRE

    Wurtsbaugh, Wayne A.; Modde, Timothy; Luecke, Chris; Courtney, Cheryl

    1990-01-01

    Juvenile rainbow trout Oncorhynchus mykiss. (ca. 80 mm S.L.) stocked into mid-elevation reservoirs in Utah are vulnerable to predation from piscivorous fish and birds. I determined how effectively juvenile trout used cover to avoid these predators by using direct observations (snorkel transects) on habitat selection in two reservoirs. Observations of juvenile trout were conducted within five weeks of stocking in 1988 and 1989. During the day juvenile trout were abundant in complex inshore hab...

  7. Factors influencing the spawning migration of female anadromous brown trout

    DEFF Research Database (Denmark)

    Svendsen, Jon Christian; Koed, Anders; Aarestrup, Kim

    2004-01-01

    Radio telemetry was employed to study movements of adult female anadromous brown trout Salmo trutta (sea trout) during upstream spawning migration and following spawning in a stream with tributaries. Sea trout were monitored by manual tracking and by automatic listening stations. The latter...

  8. Movement and mortality of stocked brown trout in a stream

    DEFF Research Database (Denmark)

    Aarestrup, Kim; Jepsen, Niels; Koed, Anders;

    2005-01-01

    The movement and mortality of stocked brown trout Salmo trutta were investigated using radio telemetry. Four brown trout left the study area whereas the remaining fish were stationary. After 5 weeks, 13 out of 50 tagged brown trout were still alive in the stream. Surviving fish had a significantly...

  9. Sensitivity of Trout to Chronic Acute Exposure to Selenium

    DEFF Research Database (Denmark)

    Nielsen, Gunnar Gissel; Nielsen, M. Gissel

    1978-01-01

    Trout were exposed to selenite (Na2SeO3) solutions of varying concentrations (0.1-100 ppm Se) for periods of up to 4 wk. A chronic exposure to 0.1 ppm Se or less is non-lethal to trout. Lethality at higher concentrations depends on the length of exposure. Trout that survive for 10 days in tap...

  10. Utilization of a rapid DNA-based assay for molecular verification of channel catfish, blue catfish, F1 hybrid, and backcross offspring at serveral life stages

    Science.gov (United States)

    The F1 hybrid offspring of channel catfish, Ictalurus punctatus, females mated with blue catfish, I. furcatus, males contain many desirable traits for commercial production such as enhanced growth and increased survivability. Although at a low efficiency, hybrids can be produced by pond spawning, b...

  11. Snorkeling as an alternative to depletion electrofishing for assessing cutthroat trout and brown trout in stream pools

    Science.gov (United States)

    Joyce, M.P.; Hubert, W.A.

    2003-01-01

    We compared abundance and length structure estimates of cutthroat trout (Oncorhynchus clarki) and brown trout (Salmo trutta) of 15 cm total length or greater obtained by snorkeling in stream pools with estimates obtained by depletion electrofishing. We sampled 12 pools in each of two streams formed by large springs in the Salt River Valley of western Wyoming. Snorkeling counts provided a relatively accurate index of depletion electrofishing estimates of abundance of cutthroat trout, but not brown trout. Linear regression analysis showed that snorkeling counts were significantly related to depletion electrofishing estimates for both cutthroat trout (P brown trout (P = 0.002), but the coefficient of determination for brown trout (r2 = 0.33) was low compared to cutthroat trout (r2 = 0.95). Frequencies of fish in three length classes observed by snorkeling and depletion electrofishing were close to being significantly different for cutthroat trout (P = 0.066) and substantially different for brown trout (P = 0.005). Snorkeling frequently failed to observe fish in the shortest length class (15-29 cm total length) of both cutthroat trout and brown trout.

  12. Use of microsatellite markers for identification of indigenous brown trout in a geographical region heavily influenced by stocked domesticated trout

    DEFF Research Database (Denmark)

    Fritzner, Niels G.; Møller Hansen, Michael; Madsen, Steffen;

    2001-01-01

    Based on estimates of genetic differentiation between populations, assignment tests and analysis of isolation by distance, stocked populations of brown trout Salmo trutta of Funen Island, Denmark, had been genetically affected by domesticated trout, whereas the stocking of wild exogenous trout into...

  13. Evaluation of Zooplankton in Hatchery Diets for Channel Catfish Fry

    Science.gov (United States)

    The efficacy of zooplankton as a supplemental hatchery diet for fry of channel catfish Ictalurus punctatus was evaluated. When a commercial diet is used as a reference, fry fed exclusively on zooplankton–either live or dried–performed poorly in their growth rate. However, when live or dried zooplan...

  14. Temperature Cycles Induce Early Maturation in Channel Catfish

    Science.gov (United States)

    A major impediment in improvement of channel catfish by selective breeding is that a high percent of fish do not spawn until the third year. If the generation time could be shortened, genetic improvement could be achieved at a faster rate. The conditions that lead to sexual maturation in fish have...

  15. Delayed feeding of channel catfish fry stocked in ponds

    Science.gov (United States)

    We compared production variables between channel catfish, Ictalurus punctatus, nursery ponds fed according to industry standards, that is feeding immediately at stocking, to an alternative practice of delaying feeding for 6 wk after stocking in an effort to utilize natural pond productivity and redu...

  16. TOXAPHENE: CHRONIC TOXICITY TO FATHEAD MINNOWS AND CHANNEL CATFISH

    Science.gov (United States)

    Fathead minnows (Pimephales promelas) and channel catfish (Ictalurus punctatus) were continuously exposed to several toxaphene concentrations (13-630 ng) in flow-through diluter systems for 8 to 10 months. Growth and backbone quality of adult fathead minnows were decreased at 97 ...

  17. Semen collection and preservation in African catfish, Clarias gariepinus

    NARCIS (Netherlands)

    Viveiros, A.T.M.

    2002-01-01

    Stock improvement using quantitative and molecular genetics is an essential part of nowadays production of farm animals and fish. To achieve this in aquaculture, germplasm of both parental sexes should be obtained in a life-saving manner. In captivity, male African catfish, Clariasgariepin

  18. Can We Improve Catfish Growth and FCR Through Oxygen Management?

    Science.gov (United States)

    Studies were conducted in 15 1-acre and six ¼-acre ponds over several years to determine the effect of low dissolved oxygen (DO) concentration on food conversion ratio (FCR), food consumption, growth, and net production of channel catfish. Control ponds in each study were maintained with a minimum D...

  19. Prevalence and enumeration of microorganisms on catfish nuggets

    Science.gov (United States)

    Catfish nuggets, either fresh or pre-packed frozen, were purchased from local retailers in the northeast United States (NJ, NY, PA, DE, and MD) and tested for microbiological quality. The microbiological background including total aerobic plate counts (APC) at 22 and 37 deg C, Enterbacteriacea, Esc...

  20. The pathology associated with visceral toxicosis of catfish

    Science.gov (United States)

    Visceral toxicosis of catfish (VTC) syndrome was recognized in the late 1990s and recently has been associated with exposure to Clostridium botulinum type E neurotoxin. Tentative diagnosis is based on clinical presentation and ross findings, and is confirmed by bioassay. In April 2009, channel cat...

  1. Channel Catfish, Ictalurus punctatus, CD63 cDNA

    Science.gov (United States)

    CD63, also known as lysosome associated membrane protein 3 (LAMP-3), is a member of tetraspanin integral membrane protein family. This protein plays many important roles in immuno-physiological functions. In this communication, we cloned, sequenced and characterized the channel catfish, CD63 transcr...

  2. Welfare of African catfish : effects of stocking density

    NARCIS (Netherlands)

    Nieuwegiessen, van de P.G.

    2009-01-01

    The general aim of this thesis was to determine the impact of stocking density on welfare indicators in African catfish, Clarias gariepinus, cultured in a recirculating aquaculture system. The following factors were studied: 1) the effects of stocking density on physical, physiological, and behaviou

  3. Relative sensitivity of bull trout (Salvelinus confluentus) and rainbow trout (Oncorhynchus mykiss) to acute copper toxicity.

    Science.gov (United States)

    Hansen, James A; Lipton, Josh; Welsh, Paul G

    2002-03-01

    Bull trout (Salvelinus confluentus) were recently listed as threatened in the United States under the federal Endangered Species Act. Past and present habitat for this species includes waterways contaminated with heavy metals released from mining activities. Because the sensitivity of this species to copper was previously unknown, we conducted acute copper toxicity tests with bull and rainbow trout (Oncorhynchus mykiss) in side-by-side comparison tests. Bioassays were conducted using water at two temperatures (8 degrees C and 16 degrees C) and two hardness levels (100 and 220 mg/L as CaCO3). At a water hardness of 100 mg/L, both species were less sensitive to copper when tested at 16 degrees C compared to 8 degrees C. The two species had similar sensitivity to copper in 100-mg/ L hardness water, but bull trout were 2.5 to 4 times less sensitive than rainbow trout in 220-mg/L hardness water. However, when our results were viewed in the context of the broader literature on rainbow trout sensitivity to copper, the sensitivities of the two species appeared similar. This suggests that adoption of toxicity thresholds that are protective of rainbow trout would be protective of bull trout; however, an additional safety factor may be warranted because of the additional level of protection necessary for this federally threatened species. PMID:11878477

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

    Science.gov (United States)

    Johnson, James H.; McKenna Jr, 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.

  5. Chitosan extends the shelf-life of filleted tilapia ( Oreochromis niloticus) during refrigerated storage

    Science.gov (United States)

    Cao, Rong; Liu, Qi; Yin, Bangzhong; Wu, Biao

    2012-09-01

    Shelf-life extension of aquatic products is of significant economical importance. To determine the potential effect of chitosan on the shelf-life of filleted tilapia, this study analyzed the bacterial community diversity in fresh and spoiled tilapia fillets stored at (4 ± 1)°C and examined the antimicrobial activity of chitosan against relevant bacteria isolates. Results showed that Pseudomonas (20%) and Aeromonas (16%) were abundant in fresh tilapia fillets, whereas Pseudomonas (52%), Aeromonas (32%) and Staphylococcus (12%) were dominant in the spoiled samples. Chitosan showed wide-spectrum antibacterial activity against bacteria isolated from tilapia and 5.0 g L-1 chitosan was selected for application in preservation. We further determined the shelf-life of chitosan-treated, filleted tilapia stored at (4 ± 1)°C based on microbiological, biochemical and sensory analyses. Results showed that the shelf-life of chitosan-treated, filleted tilapia was extended to 12 d, whereas that of untreated, control samples was 6 d. These indicate that chitosan, as a natural preservative, has great application potential in the shelf-life extension of tilapia fillets.

  6. Effects of season on ecological processes in extensive earthen tilapia ponds in Southeastern Brazil.

    Science.gov (United States)

    Favaro, E G P; Sipaúba-Tavares, L H; Milstein, A

    2015-11-01

    In Southeastern Brazil tilapia culture is conducted in extensive and semi-intensive flow-through earthen ponds, being water availability and flow management different in the rainy and dry seasons. In this region lettuce wastes are a potential cheap input for tilapia culture. This study examined the ecological processes developing during the rainy and dry seasons in three extensive flow-through earthen tilapia ponds fertilized with lettuce wastes. Water quality, plankton and sediment parameters were sampled monthly during a year. Factor analysis was used to identify the ecological processes occurring within the ponds and to construct a conceptual graphic model of the pond ecosystem functioning during the rainy and dry seasons. Processes related to nitrogen cycling presented differences between both seasons while processes related to phosphorus cycling did not. Ecological differences among ponds were due to effects of wind protection by surrounding vegetation, organic loading entering, tilapia density and its grazing pressure on zooplankton. Differences in tilapia growth among ponds were related to stocking density and ecological process affecting tilapia food availability and intraspecific competition. Lettuce wastes addition into the ponds did not produce negative effects, thus this practice may be considered a disposal option and a low-cost input source for tilapia, at least at the amounts applied in this study. PMID:26602348

  7. Brown trout and food web interactions in a Minnesota stream

    Science.gov (United States)

    Zimmerman, J.K.H.; Vondracek, B.

    2007-01-01

    1. We examined indirect, community-level interactions in a stream that contained non-native brown trout (Salmo trutta Linnaeus), native brook trout (Salvelinus fontinalis Mitchill) and native slimy sculpin (Cottus cognatus Richardson). Our objectives were to examine benthic invertebrate composition and prey selection of fishes (measured by total invertebrate dry mass, dry mass of individual invertebrate taxa and relative proportion of invertebrate taxa in the benthos and diet) among treatments (no fish, juvenile brook trout alone, juvenile brown trout alone, sculpin with brook trout and sculpin with brown trout). 2. We assigned treatments to 1 m2 enclosures/exclosures placed in riffles in Valley Creek, Minnesota, and conducted six experimental trials. We used three designs of fish densities (addition of trout to a constant number of sculpin with unequal numbers of trout and sculpin; addition of trout to a constant number of sculpin with equal numbers of trout and sculpin; and replacement of half the sculpin with an equal number of trout) to investigate the relative strength of interspecific versus intraspecific interactions. 3. Presence of fish (all three species, alone or in combined-species treatments) was not associated with changes in total dry mass of benthic invertebrates or shifts in relative abundance of benthic invertebrate taxa, regardless of fish density design. 4. Brook trout and sculpin diets did not change when each species was alone compared with treatments of both species together. Likewise, we did not find evidence for shifts in brown trout or sculpin diets when each species was alone or together. 5. We suggest that native brook trout and non-native brown trout fill similar niches in Valley Creek. We did not find evidence that either species had an effect on stream communities, potentially due to high invertebrate productivity in Valley Creek. ?? 2007 Blackwell Publishing Ltd.

  8. Production of oocytes of Nile tilapia (Oreochromis niloticus) for in vitro fertilization via hormonal treatments.

    Science.gov (United States)

    Fernandes, A F A; Alvarenga, É R; Oliveira, D A A; Aleixo, C G; Prado, S A; Luz, R K; Sarmento, N L A F; Teixeira, E A; Luz, M R; Turra, E M

    2013-12-01

    Only a few studies have described hormonal treatments for induction of synchronicity and gamete collection in Nile tilapia (Oreochromis niloticus), both important for assortative matings in breeding programmes and essential for polyploidy technologies. In this study, we compared the effectiveness of carp pituitary extract (CPE), Nile tilapia pituitary extract (TPE), human chorionic gonadotropin (hCG) and gonadotropin-releasing hormone (GnRH) protocols on the induction of spawning and egg production in Nile tilapia. Among the hormonal treatments analysed, only hCG was effective for producing viable gametes for in vitro fertilization. To verify the viability of this hormonal treatment, hCG was tested using different doses (1000, 2000, 3000, 4000 and 5000 IU/kg) in a large number of females (208 animals) from two Nile tilapia lines. The results indicated that hCG doses between 1000 and 5000 IU/kg could be used to induce final oocyte maturation in Nile tilapia with collection of stripped oocytes. This is the first study to report differential reproductive responses to hormonal treatment between tilapia lines: line 1 was more efficient at producing eggs and post-hatching larvae after hCG induction than line 2. In conclusion, we demonstrated that the hCG protocol may be applied on a large scale to induce final oocyte maturation in Nile tilapia. The development of a protocol for in vitro fertilization in Nile tilapia may aid in breeding programmes and biotechnological assays for the development of genetically modified lines of Nile tilapia. PMID:23834584

  9. Analysis of a Blue Catfish Population in a Southeastern Reservoir: Lake Norman, North Carolina

    OpenAIRE

    Grist, Joseph Daniel

    2002-01-01

    This investigation examined the diet, growth, movement, population genetics, and possible consumption demands of an introduced blue catfish Ictalurus furcatus population in Lake Norman, North Carolina. Clupeids, Corbicula fluminea, and Chara were the predominant food items (percent stomach contents by weight) found in blue catfish, and varied by season, lake-region, and fish size-class. Lake Norman blue catfish grow at a slower rate than has been reported for other reservoir populations, wi...

  10. Genomic organization of the channel catfish CD45 functional gene and CD45 pseudogenes

    OpenAIRE

    Kountikov, Evgueni; Wilson, Melanie; Miller, Norman; Clem, William; Bengtén, Eva; Quiniou, Sylvie

    2005-01-01

    CD45 is a transmembrane protein tyrosine phosphatase, which in mammals plays an important role in T and B cell receptor and cytokine signaling. Recently, a catfish cDNA was shown to contain all characteristic CD45 features: an alternatively spliced amino-terminus, a cysteine-rich region, three fibronectin domains, a transmembrane region, and two phosphotyrosine phosphatase domains. However, analyses of CD45 cDNAs from various catfish lymphoid cell lines demonstrated that catfish CD45 is uniqu...

  11. INTRA-PROCESSOR PRICE-SPREAD BEHAVIOR: IS THE U.S. CATFISH PROCESSING INDUSTRY COMPETITIVE?

    OpenAIRE

    Hudson, Darren

    1998-01-01

    An analysis was conducted of price-spread behavior in the catfish-processing sector of the United States. A model of imperfect competition using conjectural variations was used to test for significant deviations from competition. Results show no significant deviation from competitive behavior, suggesting that catfish processor behave competitively. However, this result is limited by the assumption of equal market shares by each catfish-processing firm.

  12. IQF Catfish Retail Pack: A Study of Consumers' Willingness to Pay

    OpenAIRE

    Quagrainie, Kwamena K.

    2005-01-01

    The grocery retail channel represents a potential for increased sales for catfish products because of the competitive nature that imported catfish fillets pose at foodservice market channels. The study examined the potential for selling a household-size pack of IQF 6-fillets of catfish through the grocery market channels, and consumers' willingness to pay for the product. Data used were obtained from a survey conducted in selected southern U.S. cities. Results suggest that households will pur...

  13. Evaluation of locally available feed resources for striped catfish (Pangasianodon hypophthalmus)

    OpenAIRE

    Da, Chau Thi

    2012-01-01

    This thesis investigated and compared inputs and outputs, economic factors and current feed use in small-scale farming systems producing striped catfish (Pangasianodon hypophthalmus) in the Mekong Delta. The nutrient content of locally available natural feed resources for striped catfish was determined and growth performance, feed utilisation and body indices were analysed in pond-cultured striped catfish fed diets where fish meal protein was replaced with protein from local feed resources. ...

  14. Comparative susceptibility of channel catfish, blue catfish and their hybrid cross to experimental challenge with Bolbophorus damnificus (Digenea: Bolbophoridae) cercariae

    Science.gov (United States)

    The digenetic trematode Bolbophorus damnificus has been implicated in significant losses in catfish aquaculture since the late 1990s. The complex life cycle sequentially involves the American white pelican Pelecanus erythrorhynchos, the marsh rams horn snail Planorbella trivolvis, and Channel Catfis...

  15. Iron status of channel catfish Ictalurus punctatus affected by channel catfish anemia and response to parenteral iron

    Science.gov (United States)

    Originally reported in 1983, channel catfish anemia (CCA), also ‘white lip’ or ‘no blood,’ is a major idiopathic disease affecting commercial production in the Mississippi Delta region of the USA. Affected individuals are characterized by lethargy, anorexia, extreme pallor, and packed cell volumes o...

  16. Tilapia larvae Aroclor 1254 exposure: effects on gonads and circulating thyroid hormones during adulthood.

    Science.gov (United States)

    Coimbra, A M; Reis-Henriques, M A

    2007-11-01

    Aroclor 1254 a polychlorinated biphenyls (PCBs) mixture, when administrated through the diet, was previously found to inhibit adult tilapia (Oreochromis niloticus) reproduction. Since fish larvae can be more sensitive to contaminants, the objectives of this study were to evaluate in adults the impact in gonad development and in thyroid function of Aroclor 1254 administrated at larvae stages. Aroclor 1254 exposed tilapia presented both ovary and testicular alterations and a decline in T4 plasma concentration while T3 remained unaltered. This work shows exposure to Aroclor 1254 during tilapia early life stages causes a disruption of the reproductive axis that enables reproduction. PMID:17943219

  17. Physicochemical and sensory characteristics of snack made with minced Nile tilapia

    OpenAIRE

    João De Paula Cortez Netto; Paulo Roberto Campagnoli de Oliveira Filho; Judite Lapa-Guimarães; Elisabete Maria Macedo Viegas

    2014-01-01

    Nile tilapia is one of the major fish species cultivated worldwide and in Brazil. The tilapia fillet yield is between 30-35%, thus around 70% of waste is generated. A portion of this waste can be used to obtain minced fish, and the resulting product can be used as meat raw material to prepare fish snacks. The aim of this study was to produce fish snacks containing different inclusion levels (20, 30, and 40%) of minced fish obtained from Nile tilapia processing waste and evaluate their physico...

  18. Feeding behavior and food preference of Penaeus monodon Fabricius with scrap tilapia

    OpenAIRE

    Apud, F.D.; Deatras, N.; Gonzales, K.G.

    1980-01-01

    The time of day during which P. monodon feeds at different depth levels in earthen ponds, and its preference for three types of tilapia feeds (dry, fresh and fermented) were determined. It was observed that P. monodon concentrated at the bottom beds during the day and along the periphery of dikes during night-time, with a slight tendency to swim and feed towards the surface as darkness increased. P. monodon showed special preference for dried tilapia compared to fresh and fermented tilapia. P...

  19. 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...

  20. Interaction between afternoon aeration and tilapia stocking density

    OpenAIRE

    Francisco Roberto dos Santos Lima; Davi de Holanda Cavalcante; Vanessa Tomaz Rebouças; Marcelo Vinícius do Carmo e Sá

    2016-01-01

    The present study aimed at determining the effects of the interaction between afternoon aeration and stocking density of Nile tilapia on variables of water and soil quality, growth performance and effluent quality. The experiment was a 3 x 2 factorial randomized block design, with three stocking densities (8, 12 and 16 fish per tank or 43.5, 65.3, and 87.0 g m-3) under two mechanical aeration regimes, absence (control; three replicates) and afternoon aeration (four replicates). The afternoon ...

  1. Filter System Performance in a Tilapia Recirculating System

    OpenAIRE

    Cristian Savin; Benone Păsărin; Marilena Talpeş; Gabriel Hoha; Magdalena Tenciu; Elpida Paltenea; Elena Mocanu; Adrian Gruber

    2012-01-01

    It is known that recirculating aquaculture systems, although has some advantages, production costs resulting from these production systems are quite high and is mainly due to the filtration system of technological water. Tilapia is one of the most important species in world aquaculture, the second production after carp, because of the advantages it has being reared in any production system: ponds, net-pens, cages, raceways, recirculating systems. Aim of this study was to evaluate the performa...

  2. Suitable stocking density of tilapia in an aquaponic system

    OpenAIRE

    Rahmatullah, R.; Das, M; Rahmatullah, S.M.

    2010-01-01

    An aquaponic system was studied through the integrated culture of mono-sex GIFT and two types of vegetables viz. morning glory, Ipomoea reptans and taro, Colocasia esculenta in a recirculating system for 15 weeks. Tilapia fry of uniform size of 0.76 g were released in three treatments (stocking densities): 106 fish/m³ (T1), 142 fish/m³ (T2) and 177 fish/m³ (T3) to assess the effect of stocking density on the growth performance of fish. Fish were fed with a commercial feed containing 25% prote...

  3. Adjusting to Trade Policy: Evidence from U.S. Antidumping Duties on Vietnamese Catfish

    OpenAIRE

    Irene Brambilla; Guido Porto; Alessandro Tarozzi

    2008-01-01

    In 2003, after claims of dumping, the U.S. imposed heavy tariffs on imports of catfish from Vietnam. As a result, Vietnamese exports of catfish to the U.S. market sharply declined. Using a panel data of Vietnamese households, we explore the responses of catfish producers in the Mekong delta between 2002 and 2004. We study adjustments not only in catfish aquaculture but also in other economic activities. We find that, over this period, the rate of income growth was significantly lower among ho...

  4. Effects of Endosulfan on Predator–Prey Interactions Between Catfish and Schistosoma Host Snails

    OpenAIRE

    Monde, Concillia; Syampungani, Stephen; Brink, van den, L.

    2016-01-01

    The effect of the pesticide endosulfan on predator–prey interactions between catfish and Schistosoma host snails was assessed in static tank experiments. Hybrid catfish (Clarias gariepinus × C. ngamensis) and Bulinus globosus were subjected to various endosulfan concentrations including an untreated control. The 48- and 96-h LC50 values for catfish were 1.0 and 50 values for snails were 1137 and 810 µg/L. To assess sublethal effects on the feeding of the catfish on B. globosus, endosulfan con...

  5. Dynamic Effects of Grain and Energy Prices on the Catfish Feed and Farm Sectors

    OpenAIRE

    Muhammad, Andrew; Zheng, Hualu

    2010-01-01

    This study examines the dynamic effects of grain prices and energy prices on catfish feed prices and the price of food-sized catfish at the farm level. Using the autoregressive distributed lag model and bounds testing procedure, a long-run relationship between feed and farm prices and their determinants was confirmed. Given the effect of corn and soybean meal prices on catfish feed prices, and catfish fish feed prices on farm prices, the long-run responsiveness of feed prices to a percentage ...

  6. BOB.1 of the channel catfish, Ictalurus punctatus: Not a transcriptional coactivator?

    OpenAIRE

    Richard, Mara L. Lennard; Hikima, Jun-ichi; Wilson, Melanie R.; Miller, Norman W.; Cunningham, Charles; Warr, Gregory W.

    2008-01-01

    Expression of the immunoglobulin heavy chain (IGH) locus of the channel catfish (Ictalurus punctatus)is driven by the Eμ3′ enhancer, whose core region contains two octamer motifs and a μE5 site. Orthologues of the Oct1 and Oct2 transcription factors have been cloned in the channel catfish and shown to bind to the octamer motifs within the core enhancer. While catfish Oct2 is an activator of transcription, catfish Oct1 failed to drive transcription and may act as a negative regulator of IGH tr...

  7. Use of microsatellite markers for identification of indigenous brown trout in a geographical region heavily influenced by stocked domesticated trout

    DEFF Research Database (Denmark)

    Fritzner, N.G.; Hansen, Michael Møller; Madsen, S.S.;

    2001-01-01

    Based on estimates of genetic differentiation between populations, assignment tests and analysis of isolation by distance, stocked populations of brown trout Salmo trutta of Funen Island, Denmark, had been genetically affected by domesticated trout, whereas the stocking of wild exogenous trout into...... one of the rivers had little or no impact. At the same time, there were clear indications of remaining indigenous gene pools in the Funen populations. The management implications of these findings are discussed and changes in trout release activity are recommended to avoid further mixing of trout gene...

  8. Microsatellite analyses of the trout of northwest Mexico

    Science.gov (United States)

    Nielsen, J.L.; Sage, G.K.

    2001-01-01

    The trout of northwest Mexico represent an undescribed group of fish considered part of the Oncorhynchus mykiss (Pacific trout) complex of species and subspecies. Recent genetic studies have shown these fish to have important genetic diversity and a unique evolutionary history when compared to coastal rainbow trout. Increased levels of allelic diversity have been found in this species at the southern extent of its range. In this study we describe the trout in the Sierra Madre Occidental from the rios Yaqui, Mayo, Casas Grandes and de Bavispe, and their relationship to the more southern distribution of Mexican golden trout (O. chrysogaster) using 11 microsatellite loci. Microsatellite allelic diversity in Mexican trout was high with a mean of 6.6 alleles/locus, average heterozygosity = 0.35, and a mean Fst = 0.43 for all loci combined. Microsatellite data were congruent with previously published mtDNA results showing unique panmictic population structure in the Rio Yaqui trout that differs from Pacific coastal trout and Mexican golden trout. These data also add support for the theory of headwaters transfer of trout across the Continental Divide from tributaries of the Rio de Bavispe into the Rio Casas Grandes. Rio Mayo trout share a close genetic relationship to trout in Rio Yaqui, but sample sizes from the Rio Mayo prevent significant comparisons in this study. Microsatellite analyses show significant allelic frequency differences between Rio Yaqui trout and O. chrysogaster in Sinaloa and Durango Mexico, adding further support for a unique evolutionary status for this group of northwestern Mexican trout.

  9. Laboratory evaluation of a lake trout bioenergetics model

    Science.gov (United States)

    Madenjian, Charles P.; O'Connor, Daniel V.

    1999-01-01

    Lake trout Salvelinus namaycush, aged 3 and 6 years and with average weights of 700 and 2,000 g, were grown in laboratory tanks for up to 407 d under a thermal regime similar to that experienced by lake trout in nearshore Lake Michigan. Lake trout were fed alewifeAlosa pseudoharengus and rainbow smelt Osmerus mordax, prey typical of lake trout in Lake Michigan. Of the 120 lake trout used in the experiment, 40 were fed a low ration (0.25% of their body weight per day), 40 were fed a medium ration (0.5% of their body weight per day), and 40 were fed a high ration (ad libitum). We measured consumption and growth, and we compared observed consumption with that predicted by the Wisconsin bioenergetics model. For lake trout fed the medium ration, model predictions for monthly consumption were unbiased. Moreover, predicted cumulative consumption by medium-ration lake trout for the entire experiment (320 d for smaller lake trout and 407 d for larger lake trout) agreed quite well with observed cumulative consumption; predictions were as close as within 0.1 to 5.2% of observed cumulative consumption. Even so, the model consistently overestimated consumption by low-ration fish and underestimated consumption by high-ration fish. The bias was significant in both cases, but was more severe for the low-ration trout. Because the low-ration and high-ration regimes were probably unrealistic for lake trout residing in Lake Michigan and because the model fit our laboratory data rather well for medium-ration trout, we conclude that applying the Wisconsin bioenergetics model to the Lake Michigan lake trout population in order to estimate the amount of prey fish consumed by lake trout each year is appropriate.

  10. Factors affecting the decision process of catfish consumers: An empirical study in the two biggest cities in Vietnam

    OpenAIRE

    Huynh, Mai Thi Xuan

    2007-01-01

    The consumption of catfish in Vietnam has not grown enough to match their increased production. The objective of this study is to explore the factors that influence the decision process of catfish consumers in Vietnam. The findings provide information for the Vietnamese catfish industry to better attract more domestic consumers to eat catfish. This study seeks to address its objective by examining the relationships that exist between the experiences, perceptions of product attr...

  11. Malheur River Basin cooperative bull trout/redband trout research project, annual report FY 1999; ANNUAL

    International Nuclear Information System (INIS)

    The purpose of this study is to document the seasonal distribution of adult/sub-adult bull trout (Salvelinus confluentus) in the Malheur River basin. Due to the decline of bull trout in the Columbia Basin, the United States Fish and Wildlife Service listed bull trout as a threatened species in June 1998. Past land management activities; construction of dams; and fish eradication projects in the North Fork and Middle Fork Malheur River by poisoning have worked in concert to cumulatively impact native species in the Malheur Basin (Bowers et. al. 1993). Survival of the remaining bull trout populations is severely threatened (Buchanan 1997). 1999 Research Objects are: (1) Document the migratory patterns of adult/sub-adult bull trout in the North Fork Malheur River; (2) Determine the seasonal bull trout use of Beulah Reservoir and bull trout entrainment; and (3) Timing and location of bull trout spawning in the North Fork Malheur River basin. The study area includes the Malheur basin from the mouth of the Malheur River located near Ontario, Oregon to the headwaters of the North Fork Malheur River (Map 1). All fish collected and most of the telemetry effort was done on the North Fork Malheur River subbasin (Map 2). Fish collection was conducted on the North Fork Malheur River at the tailwaters of Beulah Reservoir (RK 29), Beulah Reservoir (RK 29-RK 33), and in the North Fork Malheur River at Crane Crossing (RK 69) to the headwaters of the North Fork Malheur. Radio telemetry was done from the mouth of the Malheur River in Ontario, Oregon to the headwaters of the North Fork Malheur. This report will reflect all migration data collected from 3/1/99 to 12/31/99

  12. Do native brown trout and non-native brook trout interact reproductively?

    OpenAIRE

    Cucherousset, Julien; Aymes, J.-C.; Poulet, Nicolas; Santoul, Frédéric; Céréghino, Régis

    2008-01-01

    International audience Reproductive interactions between native and non-native species of fish have received little attention compared to other types of interactions such as predation or competition for food and habitat. We studied the reproductive interactions between non-native brook trout (Salvelinus fontinalis) and native brown trout (Salmo trutta) in a Pyrenees Mountain stream (SW France). We found evidence of significant interspecific interactions owing to consistent spatial and temp...

  13. Seasonal Differences in Steroids and Maturation-related Genes in Channel Catfish Under Normal and Accelerated Thermoperiods

    Science.gov (United States)

    Selective breeding of channel catfish, Ictalurus punctatus, is hampered by a long generation time. Female channel catfish typically spawn when they are 3-years-old; however, a low percentage of spawning may be observed at two years of age. Mature female channel catfish can spawn once annually. Their...

  14. Comprehensive survey and genomic characterization of toll-like receptors in channel catfish, Ictalurus punctatus: identification of novel fish TLRs

    Science.gov (United States)

    A comprehensive survey of channel catfish Toll-Like Receptors (TLRs) was undertaken following a genomic PCR approach based on degenerate primers. Twenty different TLRs were identified in channel catfish. Channel catfish TLR sequences were characterized by phylogenetic analysis based on their conserv...

  15. Chicken-type lysozyme in channel catfish: expression analysis, lysozyme activity, and efficacy as immunostimulant against Aeromonas hydrophila infection

    Science.gov (United States)

    To understand whether chicken-type lysozyme (Lys-c) in channel catfish was induced by infection of Aeromonas hydrophila, the transcriptional levels of Lys-c in skin, gut, liver, spleen, posterior kidney, and blood cells in healthy channel catfish was compared to that in channel catfish infected with...

  16. C DNA CLONING, CHARACTERIZATION AND EXPRESSION ANALYSIS OF CHANNEL CATFISH (ICTALURUS PUNCTATUS RAFINESQUE, 1818) PEROXIREDOXIN 6 GENE

    Science.gov (United States)

    Peroxiredoxin 6 gene (Prdx6) of channel catfish, Ictalurus punctatus, was cloned and sequenced. Total RNA from channel catfish tissues was isolated, reverse transcribed and amplified. The sequence of the channel catfish Prdx6 gene consists of 1003 nucleotides. Analysis of the nucleotide sequence ...

  17. Outbreak of betanodavirus infection in tilapia, Oreochromis niloticus (L.), in fresh water.

    Science.gov (United States)

    Bigarré, L; Cabon, J; Baud, M; Heimann, M; Body, A; Lieffrig, F; Castric, J

    2009-08-01

    A betanodavirus associated with a massive mortality was isolated from larvae of tilapia, Oreochromis niloticus, maintained in fresh water at 30 degrees C. Histopathology revealed vacuolation of the nervous system, suggesting an infection by a betanodavirus. The virus was identified by indirect fluorescent antibody test in the SSN1 cell line and further characterized by sequencing of a PCR product. Sequencing of the T4 region of the coat protein gene indicated a phylogenetic clustering of this isolate within the red-spotted grouper nervous necrosis virus type. However, the tilapia isolate formed a unique branch distinct from other betanodavirus isolates. The disease was experimentally reproduced by bath infection of young tilapia at 30 degrees C. The reservoir of virus at the origin of the outbreak remains unidentified. To our knowledge, this is the first report of natural nodavirus infection in tilapia reared in fresh water. PMID:19500206

  18. Commercial production and marketing of Nile tilapia (Oreochromis niloticus) fry in Chonburi and Chachoengsao provinces, Thailand

    OpenAIRE

    Little, D.C.; Sikawa, D; Juntana, J.

    1994-01-01

    Nile tilapia (Oreochromis niloticus) fry production and marketing in the provinces of Chonburi and Chachoengsao, Thailand are discussed, covering historical background, production methodology, transfer of technology to other region, and future trends.

  19. Phosphorous digestibility and activity of intestinal phytase in hybrid tilapia, Oreochromis niloticus X O. aureus

    Science.gov (United States)

    La Vorgna, M.W.; Hafez, Y.; Hughes, S.G.; Handwerker, T.

    2003-01-01

    Experiments were conducted to determine the degree to which phytate-bound phosphorus from plant protein sources could be used by hybrid tilapia (Oreochromis niloticus X O. aureus). Utilizing an inert marker technique with chromic oxide, hybrid tilapia in our study were effective at utilizing both inorganic and phytate phosphorus as evidenced by average apparent digestibility values of 93.2% and 90.0% for total and phytate phosphorus, respectively. Analysis of the intestinal brush border membrane of the tilapia revealed enzyme activity that was capable of hydrolyzing phytic acid. The presence of phytic acid hydrolyzing enzyme activity in the intestinal brush border provides a probable mechanism by which these hybrid tilapia are able to utilize phytate phosphorus effectively. ?? 2003 by The Haworth Press, Inc. All rights reserved.

  20. Use of fish processing waste as protein source in diet for Nile tilapia (Orechromis niloticus

    Directory of Open Access Journals (Sweden)

    Chotipuntu, P.

    2005-02-01

    Full Text Available Five diets were prepared using fish processing waste meal (FMFP to replace fish meal (FM at inclusion levels of 0, 25, 50, 75 and 100%. Frog diet was used as a control diet. Nile tilapia (Oreochromis niloticus were reared in laboratory conditions for 8 weeks. It was found that substitution levels of protein from FMFP in the tested diets reduced growth and feed efficiency of tilapia (p<0.05. However, the differences looks like significant trend especially that between the 100% substitution level and the frog diet. Substitution of FM by FMFD at 75% reduced cost of feed by 15.35%. It was concluded that up to 75% inclusion of FMFD in the diet of tilapia could support normal growth of Nile tilapia with the potential for substitution of FM.

  1. Shelf Life and Quality Study of Minced Tilapia with Nori and Hijiki Seaweeds as Natural Additives

    Directory of Open Access Journals (Sweden)

    Ingridy Simone Ribeiro

    2014-01-01

    Full Text Available The extraction of mechanically separated meat has emerged as an attractive process. However, it increases the incorporation of oxygen and, consequently, of flavors due to rancidity. Thus, preservatives must be added. The objective of this study was to evaluate the shelf life of minced tilapia to replace synthetic preservatives with Hijiki and Nori seaweeds extracts. The application of the extracts had no effect on the chemical composition of the minced tilapia. The seaweed extracts had inhibitory effect on total volatile base nitrogen. The minced tilapia complied with the microbiological standard set by Brazilin law. The panelists detected no differences in the rancid aroma and only minor differences were detected in the color of the products. It can be concluded that the minced tilapia with added seaweed extracts were within quality standards during frozen storage.

  2. Analysis of production and environmental effects of Nile tilapia and white shrimp culture in Thailand

    DEFF Research Database (Denmark)

    Ferreira, J.G.; Falconer, L.; Kittiwanich, J.;

    2015-01-01

    Two case studies from Southeast Asia are used to analyse production, environmental effects, and economic optimisation of Nile tilapia (Oreochromis niloticus) and white shrimp (Penaeus vannamei) pond culture. A projection of these data is made for the whole of Thailand. The results are analysed on a...... regional scale based on site selection using multi-criteria evaluation (MCE). Farm-scale culture was simulated for (i) tilapia monoculture in Chiang Rai; (ii) shrimp monoculture in Chanthaburi; and (iii) Integrated Multi-Trophic Aquaculture (IMTA) of tilapia and shrimp in Chon Buri. Together, these...... provinces produced 17,500 tonnes of tilapia in 2012, with a significant proportion exported to North America and Europe. Growth models for both species were developed, calibrated, and validated, and used to simulate population dynamics of cultivated animals, and sediment diagenesis and eutrophication in...

  3. Characterization of a Novel Orthomyxo-like Virus Causing Mass Die-Offs of Tilapia

    Science.gov (United States)

    Bacharach, Eran; Mishra, Nischay; Briese, Thomas; Zody, Michael C.; Kembou Tsofack, Japhette Esther; Zamostiano, Rachel; Berkowitz, Asaf; Ng, James; Nitido, Adam; Corvelo, André; Toussaint, Nora C.; Abel Nielsen, Sandra Cathrine; Hornig, Mady; Del Pozo, Jorge; Bloom, Toby; Ferguson, Hugh

    2016-01-01

    ABSTRACT Tilapia are an important global food source due to their omnivorous diet, tolerance for high-density aquaculture, and relative disease resistance. Since 2009, tilapia aquaculture has been threatened by mass die-offs in farmed fish in Israel and Ecuador. Here we report evidence implicating a novel orthomyxo-like virus in these outbreaks. The tilapia lake virus (TiLV) has a 10-segment, negative-sense RNA genome. The largest segment, segment 1, contains an open reading frame with weak sequence homology to the influenza C virus PB1 subunit. The other nine segments showed no homology to other viruses but have conserved, complementary sequences at their 5′ and 3′ termini, consistent with the genome organization found in other orthomyxoviruses. In situ hybridization indicates TiLV replication and transcription at sites of pathology in the liver and central nervous system of tilapia with disease. PMID:27048802

  4. A bridging study for oxytetracycline in the edible fillet of rainbow trout: Analysis by a liquid chromatographic method and the official microbial inhibition assay

    Science.gov (United States)

    Stehly, G.R.; Gingerich, W.H.; Kiessling, C.R.; Cutting, J.H.

    1999-01-01

    Oxytetracycline (OTC) is a drug approved by the U.S. Food and Drug Administration (FDA) to control certain diseases in salmonids and catfish. OTC is also a likely control agent for diseases of other fish species and for other diseases of salmonids and catfish not currently on the label. One requirement for FDA to extend and expand the approval of this antibacterial agent to other fish species is residue depletion studies. The current regulatory method for OTC in fish tissue, based on microbial inhibition, lacks sensitivity and specificity. To conduct residue depletion studies for OTC in fish with a liquid chromatographic method, a bridging study was required to determine its relationship with the official microbial inhibition assay. Triplicate samples of rainbow trout fillet tissue fortified with OTC at 0.3, 0.6, 1.2, 2.4, 4.8, and 9.6 ppm and fillet tissue with incurred OTC at approximately 0.75, 1.5, and 3.75 ppm were analyzed by high-performance liquid chromatography (HPLC) and the microbial inhibition assay. The results indicated that the 2 methods are essentially identical in the tested range, with mean coefficients of variation of 1.05% for the HPLC method and 3.94% for the microbial inhibition assay.

  5. Efficiency of aquatic macrophytes to treat Nile tilapia pond effluents

    Directory of Open Access Journals (Sweden)

    Henry-Silva Gustavo Gonzaga

    2006-01-01

    Full Text Available The effluents from fish farming can increase the quantity of suspended solids and promote the enrichment of nitrogen and phosphorus in aquatic ecosystems. In this context, the aim of this work was to evaluate the efficiency of three species of floating aquatic macrophytes (Eichhornia crassipes, Pistia stratiotes and Salvinia molesta to treat effluents from Nile tilapia culture ponds. The effluent originated from a 1,000-m² pond stocked with 2,000 male Nile tilapia Oreochromis niloticus. The treatment systems consisted of 12 experimental tanks, three tanks for each macrophyte species, and three control tanks (without plants. Water samples were collected from the: (i fish pond source water, (ii effluent from fish pond and (iii effluents from the treatment tanks. The following water variables were evaluated: turbidity, total and dissolved nitrogen, ammoniacal-N, nitrate-N, nitrite-N, total phosphorus and dissolved phosphorus. E. crassipes and P. stratiotes were more efficient in total phosphorus removal (82.0% and 83.3%, respectively and total nitrogen removal (46.1% and 43.9%, respectively than the S. molesta (72.1% total phosphorus and 42.7% total nitrogen and the control (50.3% total phosphorus and 22.8% total nitrogen, indicating that the treated effluents may be reused in the aquaculture activity.

  6. Mathematical modeling for digestible protein in animal feeds for tilapia

    Directory of Open Access Journals (Sweden)

    Luiz Vítor Oliveira Vidal

    2012-06-01

    Full Text Available The objective of this study was to formulate mathematical models to estimate digestible protein in some animal feeds for tilapia. Literature results of the proximate composition of crude protein, ether extract, and mineral matter, as well as digestible protein obtained in biological assays, were used. The data were subjected to multiple linear stepwise backward regression. Path analysis was performed to measure the direct and indirect effects of each independent variable on the dependent one. To validate the model, the experience used data from independent studies and values obtained from a digestibility trial with juvenile Nile tilapia testing five meat and bone meals, using the Guelph feces collecting system and chromium oxide (III as an indicator. The obtained model used to estimate digestible protein values (DP of animal origin is: DP(g kg-1 = -204.15+1.203xCP;R² = 0.953. The path coefficients showed a high direct positive effect (0.900 of crude protein on the digestible protein content. The mineral matter content has an indirect negative effect on protein digestibility (-0.710, reducing the crude protein content and quality.

  7. Mercury exposure in the freshwater tilapia Oreochromis niloticus

    International Nuclear Information System (INIS)

    Mercury (Hg) can be strongly accumulated and biomagnified along aquatic food chain, but the exposure pathway remains little studied. In this study, we quantified the uptake and elimination of both inorganic mercury [as Hg(II)] and methylmercury (as MeHg) in an important farmed freshwater fish, the tilapia Oreochromis niloticus, using 203Hg radiotracer technique. The dissolved uptake rates of both mercury species increased linearly with Hg concentration (tested at ng/L levels), and the uptake rate constant of MeHg was 4 times higher than that of Hg(II). Dissolved uptake of mercury was highly dependent on the water pH and dissolved organic carbon concentration. The dietborne assimilation efficiency of MeHg was 3.7-7.2 times higher than that of Hg(II), while the efflux rate constant of MeHg was 7.1 times lower. The biokinetic modeling results showed that MeHg was the greater contributor to the overall mercury bioaccumulation and dietary exposure was the predominant pathway. - Trophic transfer was the predominant pathway for mercury accumulation in tilapia, and methylmercury was more important in contributing to Hg accumulation than Hg(II).

  8. Mercury exposure in the freshwater tilapia Oreochromis niloticus

    Energy Technology Data Exchange (ETDEWEB)

    Wang Rui [Department of Biology, Hong Kong University of Science and Technology (HKUST), Clear Water Bay, Kowloon (Hong Kong); Wong Minghung [Croucher Institute for Environmental Sciences, and Department of Biology, Hong Kong Baptist University (Hong Kong); Wang Wenxiong, E-mail: wwang@ust.h [Department of Biology, Hong Kong University of Science and Technology (HKUST), Clear Water Bay, Kowloon (Hong Kong)

    2010-08-15

    Mercury (Hg) can be strongly accumulated and biomagnified along aquatic food chain, but the exposure pathway remains little studied. In this study, we quantified the uptake and elimination of both inorganic mercury [as Hg(II)] and methylmercury (as MeHg) in an important farmed freshwater fish, the tilapia Oreochromis niloticus, using {sup 203}Hg radiotracer technique. The dissolved uptake rates of both mercury species increased linearly with Hg concentration (tested at ng/L levels), and the uptake rate constant of MeHg was 4 times higher than that of Hg(II). Dissolved uptake of mercury was highly dependent on the water pH and dissolved organic carbon concentration. The dietborne assimilation efficiency of MeHg was 3.7-7.2 times higher than that of Hg(II), while the efflux rate constant of MeHg was 7.1 times lower. The biokinetic modeling results showed that MeHg was the greater contributor to the overall mercury bioaccumulation and dietary exposure was the predominant pathway. - Trophic transfer was the predominant pathway for mercury accumulation in tilapia, and methylmercury was more important in contributing to Hg accumulation than Hg(II).

  9. Tolerance of Nile tilapia juveniles to highly acidic rearing water

    Directory of Open Access Journals (Sweden)

    Vanessa Tomaz Rebouças

    2015-08-01

    Full Text Available The present work aimed at determining the tolerance of Nile tilapia juveniles to highly acidic rearing waters and the effects of water acidity on the quality of tank effluents. The experimental design consisted of four treatments with different water pH values (4.12 ± 0.84; 5.13 ± 0.74; 6.14 ± 0.64 and 8.06 ± 0.48, with five replicates each. No exchange of water was performed throughout the study, only water replenishment to maintain the initial level. Variables of water quality, soil, growth performance, metabolism and effluents were monitored for eight weeks. Despite the lower total ammonia nitrogen (TAN concentration in the pH 8 tanks, their levels of non-ionized ammonia (NH3 were the highest ones. At the end, the lowest body weight of fish was observed in the pH 8 tanks. There was a significant improvement in feed conversion ratio (FCR and protein efficiency ratio (PER due to to water acidification. There were reduced concentrations of NH3 in the acidified tanks’ effluents. It was concluded that the gradual water acidification up to pH 4 can improve the Nile tilapia juveniles’ growth performance.

  10. Removal of Zinc and Ferum using Tilapia Fish Scale

    Directory of Open Access Journals (Sweden)

    Nabilah Zayadi

    2013-11-01

    Full Text Available Abstract: Wastewater contains large amount of contaminants, especially heavy metals, organic toxicants, and human pathogens. Heavy metal contamination had become major problem in water pollution. The use of current treatment causes some drawback even though major pollutant in wastewater already removed. Removal of zinc and ferum from synthetic wastewater using Tilapia fish scale as biosorbent was studied. This study was focused on batch method by varying pH, biosorbent dosage, contact time and initial metal ion concentration. Adsorption characteristic of fish scale before and after treatment were analysed by Scanning Electron Microscopy (SEM, X-Ray Fluorescence (XRF, and Fourier Transform Infrared (FTIR while concentration of zinc and ferum was obtained by Inductively Coupled Plasma-Mass Spectrometer (ICP-MS and Atomic Adsorption Spectroscopy (AAS respectively. The maximum percentage removal was found at 93.52% of zinc and 65.9% of ferum under best optimum adsorption conditions: pH = 6, 4.5, biosorbent dosage = 0.02 g/100 mL, 0.8 g/100 mL, concentration = 10 ppb, 300 ppb and 3 hours contact time for ferum and zinc. The finding indicated that promising biosorption of zinc and ferum using Tilapia fish scale as biosorbent.

  11. Environmental blue light prevents stress in the fish Nile tilapia

    Directory of Open Access Journals (Sweden)

    Volpato G.L.

    2001-01-01

    Full Text Available The present study aimed to test the effects of blue, green or white light on the stress response of the Nile tilapia, Oreochromis niloticus (L.. Each color was tested on two groups of isolated adult Nile tilapia (8 replicates each: one being subjected to confinement stress, and the other not (control. A different environmental color was imposed on each compartment by covering the light source with cellophane of the respective color (green or blue; no cellophane was used for white light. The intensity of green, white and blue lights was 250, 590 and 250 lux, respectively. Basal plasma cortisol levels were determined for each fish prior to the experimental procedures. The fish were confined by being displaced toward one side of the aquarium using an opaque partition for 1 h both in the morning and the afternoon of the two consecutive days of the test. At the end of this 48-h period, plasma cortisol levels were measured again. Basal cortisol levels (ng/ml were similar for each group (ANOVA, F(2;42 = 0.77, P = 0.47. Thus, plasma cortisol levels were analyzed in terms of variation from their respective basal level. After confinement, plasma cortisol levels were not increased in fish submitted to a blue light environment. Thus, blue light prevents the confinement-induced cortisol response, an effect not necessarily related to light intensity.

  12. Environmental blue light prevents stress in the fish Nile tilapia.

    Science.gov (United States)

    Volpato, G L; Barreto, R E

    2001-08-01

    The present study aimed to test the effects of blue, green or white light on the stress response of the Nile tilapia, Oreochromis niloticus (L.). Each color was tested on two groups of isolated adult Nile tilapia (8 replicates each): one being subjected to confinement stress, and the other not (control). A different environmental color was imposed on each compartment by covering the light source with cellophane of the respective color (green or blue; no cellophane was used for white light). The intensity of green, white and blue lights was 250, 590 and 250 lux, respectively. Basal plasma cortisol levels were determined for each fish prior to the experimental procedures. The fish were confined by being displaced toward one side of the aquarium using an opaque partition for 1 h both in the morning and the afternoon of the two consecutive days of the test. At the end of this 48-h period, plasma cortisol levels were measured again. Basal cortisol levels (ng/ml) were similar for each group (ANOVA, F(2;42) = 0.77, P = 0.47). Thus, plasma cortisol levels were analyzed in terms of variation from their respective basal level. After confinement, plasma cortisol levels were not increased in fish submitted to a blue light environment. Thus, blue light prevents the confinement-induced cortisol response, an effect not necessarily related to light intensity. PMID:11471044

  13. Filter System Performance in a Tilapia Recirculating System

    Directory of Open Access Journals (Sweden)

    Cristian Savin

    2012-10-01

    Full Text Available It is known that recirculating aquaculture systems, although has some advantages, production costs resulting from these production systems are quite high and is mainly due to the filtration system of technological water. Tilapia is one of the most important species in world aquaculture, the second production after carp, because of the advantages it has being reared in any production system: ponds, net-pens, cages, raceways, recirculating systems. Aim of this study was to evaluate the performance of a filter system in a tilapia recirculating system. Experiments were conducted during October – December 2011, during which feeding was done only with feed, Nutra category, ageappropriate granulation. Main physical – chemical parameters of technological water were monitored, pH, dissolved oxygen, nitrite, ammonia and ammonium, both the water entry in the filter and the exit from the filter. Filtration efficiency varied from 2-3% and up to 50-60%, mainly due to rapid loading of the filter and its need for cleaning.

  14. Characteristics of Bone Gelatin Tilapia (Oreochromis niloticus) Processed by Using Hydrolysis With Phosphoric Acid and Papain Enzyme

    OpenAIRE

    Gugun Hidayat; Eko Nurcahya Dewi; Laras Rianingsih

    2016-01-01

    Phosphoric acid and papain enzyme able to hydrolyzing collagen from Tilapia into gelatin . The purpose of this research was to determine the best concentration of phosphoric acid and papain enzyme and to determine the physicochemical characteristic gelatin to from Tilapia fish bone which processed with phosphoric acid and papain enzyme. The first research phase was making bone gelatin tilapia using phosphoric acid at concentration of 4%, 5% and 6%, and the papain enzyme 0.5%, 1% a...

  15. 75 FR 38768 - Ashley National Forest, UT, High Uintas Wilderness-Colorado River Cutthroat Trout Habitat...

    Science.gov (United States)

    2010-07-06

    ... Forest Service Ashley National Forest, UT, High Uintas Wilderness--Colorado River Cutthroat Trout Habitat...) proposes to restore genetically pure Colorado River cutthroat trout (CRCT; Onchorhynchus clarki pleuriticus... District. Nonnative fish species to be removed are primarily brook trout (Salvelinus...

  16. Efficiency of baited hoop nets for sampling catfish in southeastern U.S. small impoundments

    Science.gov (United States)

    Wallace, Benjamin C.; Weaver, Daniel M.; Kwak, Thomas J.

    2011-01-01

    Many U.S. natural resource agencies stock catfish (Ictaluridae) into small impoundments to provide recreational fishing opportunities. However, effective standardized methods for sampling catfish in small impoundments have not been developed for wide application, particularly in the southeastern United States. We evaluated the efficiency of three bait treatments (i.e., soybean cake, sunflower cake, and no bait) of tandem hoop nets in two North Carolina small impoundments during the fall of 2008 and spring of 2009 in a factorial experimental design. The impoundments were stocked with catchable-size channel catfish Ictalurus punctatus at contrastingly low (5.5 fi sh/ha) and high (90.0 fi sh/ha) rates prior to our sampling. Nets baited with soybean cake consistently sampled more channel catfish than any other treatment. Channel catfish catch ranged as high as 3,251 fi sh per net series during the fall in nets baited with soybean cake in the intensively stocked impoundment and was up to 8.5 and 15.3 times higher during the fall than in the spring in each impoundment. Nets baited with soybean cake sampled significantly (12 and 24 times) more channel catfish than those with no bait in the two impoundments. These trends did not occur among other catfish species. Nonictalurid fish and turtle catch was higher during spring compared to that of fall, corresponding with low channel catfish catches. Our results indicate that tandem hoop nets baited with soybean cake during the fall is a more efficient method for sampling channel catfish compared to nets baited with sunflower cake or no bait in spring or fall. Our findings validate this technique for application in southeastern U.S. small impoundments to assess catfish abundance to guide management and evaluate the success of catfish stocking programs.

  17. In vivo and in vitro CYP1B mRNA expression in channel catfish.

    Science.gov (United States)

    Willett, Kristine L; Ganesan, Shobana; Patel, Monali; Metzger, Christine; Quiniou, Sylvie; Waldbieser, Geoff; Scheffler, Brian

    2006-07-01

    Our goal was to study the induction of CYP1B mRNA expression in channel catfish (Ictalurus punctatus). CYP1B belongs to the cytochrome P450 superfamily of genes, is involved in the oxidation of endogenous and exogenous compounds, and could potentially be a useful biomarker in fish for exposure to AhR ligands. The full-length catfish CYP1B cDNA is 2417 nt to the polyA tail and encodes a putative protein of 536 amino acids. It has 67% amino acid similarity to carp and zebrafish CYP1B and 68% similarity to carp CYP1B2. Male channel catfish were collected from three Mississippi Delta sites: Lake Roebuck, Itta Bena; Bee Lake, Thornton; and Sunflower River, Indianola. Total RNA was isolated from wild-caught catfish gill, blood, gonad and liver tissues. Quantitative real-time reverse transcriptase PCR was used to determine relative induction of CYP1B in wild catfish compared to laboratory control and BaP-exposed catfish (20mg/kg i.p. after 4 days). BaP exposure significantly induced CYP1B message in blood, gonad, and liver of laboratory catfish. In these same tissues of wild catfish from sites with relatively low sediment contaminants, CYP1B message was not statistically increased relative to laboratory control catfish. CYP1B transcript abundance was higher in gills compared to other tissues in both laboratory and wild catfish. When primary cultured gill cells were treated with increasing concentrations of BaP, TCDD, and PCBs 77, 126 and 169, CYP1B mRNA was induced more than 10-fold while PCB153 and 4,4'DDT did not cause significant CYP1B induction. Our results suggest that catfish CYP1B is induced by the classic AhR ligands. PMID:16697458

  18. Selectivity of three aquatic weeds as diet for Nile tilapia (Oreochromis niloticus)

    OpenAIRE

    Agbede, S.A.; Akinyemi, O.; A. E. Falaye; Atsanda, N. N.; Adeyemo, A.O.; Adesina, A. A.

    2001-01-01

    A total of sixty juvenile Oreochromis niloticus (Nile tilapia) were fed three species of aquatic weed, namely Azolla filiculoides (water fern), Elodea sp. and Pistia stratiotes (water lettuce) to determine which of the weeds will be selectively consumed, and preferred of all. A control group of twenty Nile tilapia was fed compounded feed. The selectivity of the weeds was observed based on their utilization as food source, and Azolla filiculoides was found to be highly utilized, followed by El...

  19. Effects of growth hormone transgenesis on metabolic rate, exercise performance and hypoxia tolerance in tilapia hybrids

    DEFF Research Database (Denmark)

    McKenzie, DJ; Martinez, R; Morales, A;

    2003-01-01

    tilapia also exhibited the same capacity to regulate oxygen uptake during progressive hypoxia, despite the fact that the GHT fish were defending a higher demand for O2. The results indicate that ectopic expression of GH raises metabolic rate in tilapia, but the fish compensate for this metabolic load and...... preserve such physiological determinants of fitness as aerobic scope, swimming performance and tolerance of hypoxia....

  20. First Occurrence Of The Tilapia Oreochromis Niloticus Niloticus (Linnaeus, 1758) In Lesina Lagoon (Eastern Italian Coast)

    OpenAIRE

    G. SCORDELLA; Lumare, F; Conides, A.; C. PAPACONSTANTINOU

    2012-01-01

    Individuals of the tilapia species Oreochromis niloticus niloticus(Linnaeus, 1758) were caught in Lesina Lagoon during experimental sampling for the shrimp Penaeus kerathurus using fyke net traps from December 1999 to September 2000. The species O. niloticusis not native in Italian coastal waters, although attempts of tilapia culture in land-based aquaculture farms were occasionally carried out in the past. The number of individuals captured in the samples suggests a colonization of the area ...

  1. Small scale commercial production of tilapia fingerlings in floating bamboo net-hapas

    OpenAIRE

    Otubusin, S.O.

    1987-01-01

    The inadequate supply of tilapia seed is considered as one of the major present constraints to the development of the culture industry in Nigeria. The floating bamboo net-hapa hatchery/nursery system was observed to be very efficient in the mass production of tilapia (Oreochromis niloticus) fry and fingerlings at Kainji Lake Research Institute. This system was therefore, recommended for small-scale (artisanal) commercial operators consisting of fishermen families in order to increase their pr...

  2. ISOLATION AND DETERMINATION OF TYPE I COLLAGEN FROM TILAPIA (Oreochromis niloticus) WASTE

    OpenAIRE

    S.Sujithra; N.Kiruthiga; M.J. Prabhu; R.Kumeresan

    2013-01-01

    Tilapia are one of the most widely introduced fish globally that has clearly emerged as a promising group in aquaculture. Oreochromis niloticus was the first Tilapia species to be taken up for large Scaleaquaculture. It is consumed widely due to its deliciousness and rich source of protein. During its processing, the scales, Fins, Skins etc are expelled out as waste Acid solubilized collagen (ASC) and Pepsin Solubilizedcollagen (PSC) were extracted from these processing wastes. Initial extrac...

  3. AEROMONAS SALMONICIDA INFECTION IN VACCINATED RAINBOW TROUT

    DEFF Research Database (Denmark)

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

    causing furunculosis. Rainbow trout (Oncorhynchus mykiss) were vaccinated with two trivalent adjuvanted experimental vaccines containing formalin-killed A. salmonicida, Vibrio anguillarum O1 and O2a and a commercial corresponding vaccine (Alpha Ject 3000). Fish were challenged by i.p. injection or...

  4. Oral Vaccination of Channel Catfish against Enteric Septicemia of Catfish Using a Live Attenuated Edwardsiella ictaluri Isolate.

    Science.gov (United States)

    Wise, David J; Greenway, Terrence E; Byars, Todd S; Griffin, Matt J; Khoo, Lester H

    2015-06-01

    Enteric septicemia of catfish (ESC), caused by Edwardsiella ictaluri, is the most problematic bacterial disease affecting catfish aquaculture in the southeastern United States. Efforts to develop an effective ESC vaccine have had limited industrial success. In commercial settings, ESC vaccines are typically administered by immersion when fry are transferred from the hatchery to rearing ponds. While this approach is a practical method of mass delivery, this strategy administers vaccines to very young fish, which lack a fully developed immune system. To circumvent this limitation, an oral vaccination strategy was evaluated as a means of immunizing catfish at the fingerling stage of production, when fish possess a more complete immune arsenal. A virulent E. ictaluri isolate (S97-773) was attenuated by successive passage on media containing increasing concentrations of rifamycin. In laboratory trials, cultured vaccine was diluted and mixed with feed (100 mL diluted vaccine/454 g feed). This mixture was then fed to Channel Catfish Ictalurus punctatus fingerlings. Two separate dilutions of cultured vaccine (1:10 and 1:100) were used to create the vaccine-feed mixture, equating to estimated doses of 5 × 10⁷ and 5 × 10⁶ CFU/g of feed, respectively. After 30 d, catfish were exposed by immersion (1 × 10⁶ CFU/mL) to the virulent parental strain of E. ictaluri. The target dose (1:100 dilution, ∼5 × 10⁶ CFU/g of feed) offered exceptional protection (relative percent survival = 82.6-100%). In addition, negligible deaths occurred in fish vaccinated at 10 times the target dose (1:10 dilution, ∼5 × 10⁷ CFU/g of feed). In pond trials, antibody production increased 18-fold in orally vaccinated fish. When compared with nonvaccinated controls, vaccination significantly improved survival, feed fed, feed conversion, biomass produced, and total harvest. This research demonstrates Channel Catfish can be successfully immunized in a commercial setting against E. ictaluri

  5. EXTRACTION AND DETERMINATION OF COLLAGEN PEPTIDE AND ITS CLINICAL IMPORTANCE FROM TILAPIA FISH SCALES (OREOCHROMIS NILOTICUS

    Directory of Open Access Journals (Sweden)

    M.Hemanth kumar

    2011-10-01

    Full Text Available Tilapia are one of the most widely introduced fish globally that has clearly emerged as a very promising group in aquaculture. Oreochromis mossambicus was the first tilapia species to be taken up for large scale aquaculture, followed by Oreochromis niloticus, Oreochromis aureus and Tilapia rendalli. Today O. niloticus contributes more than 80% of tilapia aquaculture production globally. O. mossambicus was introduced in India as early as 1952 with a view to filling some unoccupied ecological niches, mainly pond aquaculture and reservoir fisheries. Tilapia fish scales found to have more percentage of Type I collagen. Fish collagen is complex structural protein that helps to maintain the strength and flexibility of skin, ligaments, bones, joints, muscles, tendons, gums, eyes, blood vessels, nails and hair. Collagen can be obtained from fish scales, fish skins by advanced enzymatic digestion methods in biotechnology. The Protein content of the above is more than 90% and having 18 kinds of amino acids out of which 7 are essential for human consumption. These products are easily absorbable and having high biological value promoting the absorption of vitamins and minerals. The enzymatic digestion technology process releases a lot of peptides in molecular collagen that helps humans in many physiological functions. Collagen has been used in biomedical pharmaceutical, food and cosmetic industries. In this paper we have determined the collagen extracted from Tilapia fish scales and also its clinical importance.

  6. Chitosan Extends the Shelf-life of Filleted Tilapia (Oreochromis niloticus) During Refrigerated Storage

    Institute of Scientific and Technical Information of China (English)

    CAO Rong; LIU Qi; YIN Bangzhong; WU Biao

    2012-01-01

    Shelf-life extension of aquatic products is of significant economical importance.To determine the potential effect of chitosan on the shelf-life of filleted tilapia,this study analyzed the bacterial community diversity in fresh and spoiled tilapia fillets stored at(4±1)℃ and examined the antimicrobial activity of chitosan against relevant bacteria isolates.Results showed that Pseudomonas(20%)and Aeromonas(16%)were abundant in fresh tilapia fillets,whereas Pseudomonas(52%),Aeromonas(32%)and Staphylococcus(12%)were dominant in the spoiled samples.Chitosan showed wide-spectrum antibacterial activity against bacteria isolated from tilapia and 5.0 g L-1 chitosan was selected for application in preservation.We further determined the shelf-life of chitosan-treated,filleted tilapia stored at(4±1)℃ based on microbiological,biochemical and sensory analyses.Results showed that the shelf-life of chitosan-treated,filleted tilapia was extended to 12 d,whereas that of untreated,control samples was 6 d.These indicate that chitosan,as a natural preservative,has great application potential in the shelf-life extension oftilapia fillets.

  7. Genetically-Improved Tilapia Strains in Africa: Potential Benefits and Negative Impacts

    Directory of Open Access Journals (Sweden)

    Yaw B. Ansah

    2014-06-01

    Full Text Available Two genetically improved tilapia strains (GIFT and Akosombo have been created with Oreochromis niloticus (Nile tilapia, which is native to Africa. In particular, GIFT has been shown to be significantly superior to local African tilapia strains in terms of growth rate. While development economists see the potential for food security and poverty reduction in Africa from culture of these new strains of tilapia, conservationists are wary of potential ecological and genetic impacts on receiving ecosystems and native stocks of tilapia. This study reviews the history of the GIFT technology, and identifies potential environmental and genetic risks of improved and farmed strains and tilapia in general. We also estimate the potential economic gains from the introduction of genetically improved strains in Africa, using Ghana as a case country. Employing a combination of the Economic-Surplus model and Monte Carlo simulation, we found the mean net present value (NPV of the introduction of the GIFT strain in Ghana to be approximately 1% of the country’s gross domestic product. Sensitivity analysis indicated that the difference in growth or yield between the GIFT and locally-available strains has the largest effect on mean NPV. We conclude that improvements in management practices and infrastructure could increase the yield and profitability of the local strains even if genetically-improved strains are not introduced. These improvements also will ensure the realization of the full potential of introduced strains.

  8. Comparative Transcriptome Analysis Identifies Candidate Genes Related to Skin Color Differentiation in Red Tilapia.

    Science.gov (United States)

    Zhu, Wenbin; Wang, Lanmei; Dong, Zaijie; Chen, Xingting; Song, Feibiao; Liu, Nian; Yang, Hui; Fu, Jianjun

    2016-01-01

    Red tilapia is becoming more popular for aquaculture production in China in recent years. However, the pigmentation differentiation in genetic breeding is the main problem limiting its development of commercial red tilapia culture and the genetic basis of skin color variation is still unknown. In this study, we conducted Illumina sequencing of transcriptome on three color variety red tilapia. A total of 224,895,758 reads were generated, resulting in 160,762 assembled contigs that were used as reference contigs. The contigs of red tilapia transcriptome had hits in the range of 53.4% to 86.7% of the unique proteins of zebrafish, fugu, medaka, three-spined stickleback and tilapia. And 44,723 contigs containing 77,423 simple sequence repeats (SSRs) were identified, with 16,646 contigs containing more than one SSR. Three skin transcriptomes were compared pairwise and the results revealed that there were 148 common significantly differentially expressed unigenes and several key genes related to pigment synthesis, i.e. tyr, tyrp1, silv, sox10, slc24a5, cbs and slc7a11, were included. The results will facilitate understanding the molecular mechanisms of skin pigmentation differentiation in red tilapia and accelerate the molecular selection of the specific strain with consistent skin colors. PMID:27511178

  9. Species diversity defends against the invasion of Nile tilapia (Oreochromis niloticus

    Directory of Open Access Journals (Sweden)

    Gu Dang E.

    2014-05-01

    Full Text Available Nile tilapia (Oreochromis niloticus is one of the most widely cultured species globally and has successfully colonized much of the world. Despite numerous studies of this exotic species, how differences in native communities mitigate the consequences of Nile tilapia invasion is unknown. Theory predicts that communities that are more diverse should be more resistant to exotic species, an effect that is referred to as “biotic resistance”, but these effects are spatially dependent and organism-specific. Field surveys and laboratory experiments were conducted to test the theory of “biotic resistance” and ascertain the relationship between native species richness and the invasion of Nile tilapia. In the field, we found that as native species richness increased, the biomass of Nile tilapia was significantly reduced. Consistent with results from the field, our manipulative experiment indicated that the growth of Nile tilapia was negatively related to native species richness. Thus, our study supports the theory of “biotic resistance” and suggests that species biodiversity represents an important defense against the invasion of Nile tilapia.

  10. Energy costs of catfish space use as determined by biotelemetry.

    Directory of Open Access Journals (Sweden)

    Ondřej Slavík

    Full Text Available Animals use dispersed resources within their home range (HR during regular day-to-day activities. The high-quality area intensively used by an individual, where critical resources are concentrated, has been designated as the core area (CA. This study aimed to describe how animals utilize energy in the HR and CA assuming that changes would occur according to the size of the used areas. We observed energetic costs of space use in the largest European freshwater predator catfish, Silurus glanis, using physiological sensors. Catfish consumed significantly more energy within the CA compared to the rest of the HR area. In addition, energetic costs of space use within a large area were lower. These results generally indicate that utilization of larger areas is related to less demanding activities, such as patrolling and searching for new resources and mates. In contrast, fish occurrence in small areas appears to be related to energetically demanding use of spatially limited resources.

  11. DNA damage and radiocesium in channel catfish from Chernobyl

    International Nuclear Information System (INIS)

    The explosion of the Chernobyl Nuclear Power Plant resulted in some of the most radioactively contaminated habitats on earth. Despite evacuation of all human inhabitants from the most contaminated areas, animals and plants continue to thrive in these areas. This study examines the levels of contamination and genetic damage associated with cesium-137 in catfish (Ictalurus punctatus) from the cooling pond and a control site. In general, catfish from the cooling pond exhibit greater genetic damage, and the amount of damage is related to the concentration of radiocesium in individual fish. Genetic damage is primarily in the form of DNA strand breaks, with few micronuclei being observed in contaminated fish. The possible roles that acclimation and adaption play in the response to high levels of radiation exposure are discussed

  12. Complete mitochondrial genome of catfish Eutropiichthys vacha (Hamilton, 1822).

    Science.gov (United States)

    Punhal, Lashari; Laghari, Muhammad Younis; Waryani, Baradi; Jalbani, Shaista; Narejo, Naeem Tariq; Zhang, Yan

    2016-09-01

    Complete mitochondrial genome of catfish, Eutropiichthys vacha, was isolated by LA PCR (TakaRa LAtaq, Dalian, China); and sequenced by Sanger's method to obtain the complete mitochondrial genome, which is listed Critically Endangered and Red-listed species. The complete mitogenome was 16,478 bp in length and contains 13 typical vertebrate protein-coding genes, 2 rRNA and 22 tRNA genes. The whole genome base composition was estimated to be 31.06% A, 27.59% C, 15.65% G, and 25.68% T. The complete mitochondrial genome of catfish, E. vacha provides the fundamental tool for genetic breeding and conservation studies. PMID:25630731

  13. Production of enzymatic protein hydrolysates from freshwater catfish (Clarias batrachus)

    Science.gov (United States)

    Seniman, Maizatul Sarah Md; Yusop, Salma Mohamad; Babji, Abdul Salam

    2014-09-01

    Fish protein hydrolysate (FPH) was prepared from freshwater catfish (Clarias batrachus) by using Alcalase® 2.4L and Papain. The effect of hydrolysis time (30, 60, 120, 180 min) with enzyme concentration of 1% (v/w substrate); pH = 8.0, 7.0 was studied to determine the degree of hydrolysis (DH), peptide content, proximate composition and amino acid profile. Results showed that the highest DH of Alcalase and Papain FPH were 58.79% and 53.48% after 180 min at 55°C incubation respectively. The peptide content of both FPH increased as hydrolysis time increases. FPH showed higher crude protein content and lower fat, moisture and ash content compared to raw catfish. The major amino acids of both hydrolysates were Glu, Lys and Asp. Content of essential amino acids of Alcalase and Papain hydrolysates were 44.05% and 43.31% respectively.

  14. Bioaccumulation of P-32 in bluegill and catfish

    International Nuclear Information System (INIS)

    Bluegill and catfish were fed P-32 at a constant feeding rate per body weight to determine the bioaccummulation factor (BF/sub r/) for P-32 in muscle relative to water. The fish were maintained in flow-through tanks at two feeding levels. The bluegill accumulated P-32 for 51 days, followed by depuration for 28 days. The catfish study had to be teminated after 11 days. Fish were analyzed in triplicte for P-32 and phosphorus at intervals of 1 to 8 days. Additional aquaria experiments were performed to determine the effects of water temperature, feeding rate, and type of food (worms vs. pellets) on P-32 uptake, and to observe P-32 uptake from water by unfed fish (including fish with blocked esophagus). A simple calculational model was used to determine the phosphorus turnover constant from the specific activity in tissue relative to food. This ratio at steady state approaches the BF/sub r/BF ratio (where BF is the phosphorus bioaccumulation factor) if P-32 transfers rapidly from water to food. The bluegill showed a weight gain of 0.2 %/d, a phosphorous turnover constant in muscle of 0.43 %/d, and a BF/sub r//BF ratio of 0.081 at the higher feeding rate, and 0.05 %/d, 0.34 %/d, and 0.064 at the lower feeding rate. Hence, respective P-32 BF/sub r/ values are 6000 and 4000 at a phosphorus BF of 70,000. The BF/sub r/ values for catfish were approximately twice as high. The aquarium experiments suggest that the higher factors are due to a much higher phosphorus intake, higher water temperature, higher retention from pellets than from worms, and possible higher retention by catfish than bluegill under the same conditions. 36 references, 15 figures, 22 tables

  15. DNA Barcoding of Catfish: Species Authentication and Phylogenetic Assessment

    OpenAIRE

    Wong, Li Lian; Peatman, Eric; Lu, Jianguo; Kucuktas, Huseyin; He, Shunping; Zhou, Chuanjiang; Na-Nakorn, Uthairat; Liu, Zhanjiang

    2011-01-01

    As the global market for fisheries and aquaculture products expands, mislabeling of these products has become a growing concern in the food safety arena. Molecular species identification techniques hold the potential for rapid, accurate assessment of proper labeling. Here we developed and evaluated DNA barcodes for use in differentiating United States domestic and imported catfish species. First, we sequenced 651 base-pair barcodes from the cytochrome oxidase I (COI) gene from individuals of ...

  16. The Neotropical whale catfishes (Siluriformes: Cetopsidae: Cetopsinae), a revisionary study

    OpenAIRE

    Vari, Richard P.; Carl J. Ferraris Jr.; Mário C. C. de Pinna

    2005-01-01

    The catfishes of the subfamily Cetopsinae of the Neotropical family Cetopsidae are revised. Four genera, Cetopsidium new genus, Cetopsis, Denticetopsis, and Paracetopsis Bleeker are recognized as valid. Bathycetopsis, Hemicetopsis, and Pseudocetopsis are considered synonyms of Cetopsis and Paracetopsis Eigenmann & Bean and Cetopsogiton synonyms of Paracetopsis. Thirty-seven species are recognized in the Cetopsinae. Cetopsidium includes six species: C. ferreirai, new species, rio Trombetas; C....

  17. Basic steps in the production of the African catfish seed

    OpenAIRE

    Ondhoro, C.C.; Mwanja, T.M.

    2014-01-01

    A typical production cycle for African catfish farming begins with a selection of fingerlings or juvenile fish of good quality for brood stock development. Fish are selected from a family or grow out stock basing on records of the origin,age, strain and performance history of the parents or from the wild in this brochure, we explain the basic steps and requirements a farmer needs in order to achieve good results in the hatchery.

  18. Assembly of 500,000 inter-specific catfish expressed sequence tags and large scale gene-associated marker development for whole genome association studies

    OpenAIRE

    Wang, Shaolin

    2010-01-01

    Background-Through the Community Sequencing Program, a catfish EST sequencing project was carried out through a collaboration between the catfish research community and the Department of Energy's Joint Genome Institute. Prior to this project, only a limited EST resource from catfish was available for the purpose of SNP identification. Results-A total of 438,321 quality ESTs were generated from 8 channel catfish (Ictalurus punctatus) and 4 blue catfish (Ictalurus furcatus) libraries, bringing ...

  19. Assembly of 500,000 inter-specific catfish expressed sequence tags and large scale gene-associated marker development for whole genome association studies

    OpenAIRE

    Wang, Shaolin; Peatman, Eric; Abernathy, Jason; Waldbieser, Geoff; Lindquist, Erika; Richardson, Paul; Lucas, Susan; Wang, Mei; Li, Ping; Thimmapuram, Jyothi; Liu, Lei; Vullaganti, Deepika; Kucuktas, Huseyin; Murdock, Christopher; Small, Brian C

    2010-01-01

    Background Through the Community Sequencing Program, a catfish EST sequencing project was carried out through a collaboration between the catfish research community and the Department of Energy's Joint Genome Institute. Prior to this project, only a limited EST resource from catfish was available for the purpose of SNP identification. Results A total of 438,321 quality ESTs were generated from 8 channel catfish (Ictalurus punctatus) and 4 blue catfish (Ictalurus furcatus) libraries, bringing ...

  20. A First Generation Bac-Based Physical Map of the Channel Catfish Genome

    Science.gov (United States)

    Background: Channel catfish, Ictalurus punctatus, is the leading species in North American aquaculture. Genetic improvement of catfish is performed through selective breeding, and genomic tools will help improve selection efficiency. A physical map is needed to integrate the genetic map with the kar...

  1. Stomach Contents of the Catfish (Clarias gariepinus Burchell, 1822) in the River Asi (Turkey)

    OpenAIRE

    YALÇIN, Şükran

    2001-01-01

    Natural food items of catfish (Clarias gariepinus Burchell, 1822) were investigated in the River Asi from September 1996 to October 1998. Analyses of stomach contents showed that the catfish feed basically on Arthropoda, mostly Diptera larvae, and on plant materials to a considerable extent. A successful filter feeding was observed, especially during the summer period.

  2. A trap panel for in-pond raceways to capture escaped catfish

    Science.gov (United States)

    The first commercial-scale in-pond raceway system (IPRS) used to produce catfish in west Alabama was constructed from funds by a joint effort involving the Alabama Catfish Producers Association, Dean Wilson Farms, and Auburn University. The goal of this project was to improve profitability of catfis...

  3. Response of channel x blue hybrid catfish to chronic diurnal hypoxia

    Science.gov (United States)

    Performance traits and metabolic responses of the channel x blue hybrid catfish (Ictalurus punctatus female x I. furcatus male) in response to chronic diurnal hypoxia were evaluated in this 197-d study. Sixteen 0.1-ha earthen ponds were stocked with 15,169 hybrid catfish/ha (47 g/fish) and managed t...

  4. Infection and disease progress of motile Aeromonas septicemia caused by virulent Aeromonas hydrophila in channel catfish

    Science.gov (United States)

    Motile Aeromonas septicemia (MAS), caused by virulent clonal isolates of Aeromonas hydrophila (vAh), is emerging as a major disease in channel catfish (Ictalurus punctatus) aquaculture in the Southeastern United States. Predisposing conditions leading to vAh infection in catfish were however largely...

  5. Experimental induction of motile Aeromonas septicemia in channel catfish by waterborne challenge with virulent Aeromonas hydrophila

    Science.gov (United States)

    Motile Aeromonas septicemia (MAS), caused by virulent clonal isolates of Aeromonas hydrophila (vAh), is emerging as a major disease in catfish aquaculture in the Southeastern United States. Predisposing conditions leading to vAh infection in catfish were however largely unknown. The objective of thi...

  6. 2010 Surveillance for Aeromonas hydrophila outbreaks in the Alabama catfish industry

    Science.gov (United States)

    In 2009, a virulent strain of Aeromonas hydrophila was associated with severely acute to chronic mortality in catfish ponds in Alabama. This strain of A. hydrophila had not been previously identified in AL catfish. In a joint effort between the USDA ARS and Auburn University, a combination of appr...

  7. Comparative genomics of Aeromonas hydrophila isolates from an epidemic in channel catfish

    Science.gov (United States)

    Background Aeromonas hydrophila was identified as the etiologic agent infecting farmed channel catfish in 2009/2010, resulting in higher mortality rates than typical for motile Aeromonas septicemia with over 5 million pounds of catfish lost to this outbreak. The biochemistry, molecular phylogeny, an...

  8. Remediation of uranium-contaminated groundwater by sorption onto hydoxyapatite derived from catfish bones

    Science.gov (United States)

    Hydroxyapatite was prepared from catfish bones, called catfish hydroxyapatite (CFHA), by mechanical and chemical treatment methods and was characterized by x-ray diffraction (X-RD) and scanning electron microscope (SEM) techniques to confirm the presence of hydroxyapatite. The ability of CFHA to rem...

  9. Expression Profiles of Cloned Channel Catfish (Ictalurus punctatus) Lymphoid Cell Lines and Mixed Lymphocyte Cultures

    Science.gov (United States)

    Clonal channel catfish lymphoid cell lines and mixed lymphocyte cultures (MLC) have proven extremely useful in examining immune responses at the cellular and molecular levels. To date clonal catfish cell lines and MLC have been biologically and phenotypically characterized using a variety of techniq...

  10. CLONING AND SEQUENCING OF CHANNEL CATFISH (ICTALURUS PUNCTATUS) MATRIX METALLOPROTEINASE-9

    Science.gov (United States)

    In the course of studying pathogenesis of enteric septicemia of catfish, we noted that channel catfish matrix metalloproteinase-9 (MMP-9) gene was up-regulated after Edwardsiella ictaluri infection. In this study, we cloned and sequenced using the RACE. The complete sequence of the CC MMP-9 cDNA g...

  11. Molecular Cloning and Sequencing of Hemoglobin-Beta Gene of Channel Catfish, Ictalurus Punctatus Rafinesque

    Science.gov (United States)

    : Hemoglobin-y gene of channel catfish , lctalurus punctatus, was cloned and sequenced . Total RNA from head kidneys was isolated, reverse transcribed and amplified . The sequence of the channel catfish hemoglobin-y gene consists of 600 nucleotides . Analysis of the nucleotide sequence reveals one o...

  12. Molecular Cloning, Expression and Genome Organization of Channel Catfish (Ictalurus punctatus) Matrix Metalloproteinase-9

    Science.gov (United States)

    In the course of studying pathogenesis of enteric septicemia of catfish, we noted that channel catfish matrix metalloproteinase-9 (MMP-9) gene was up-regulated after Edwardsiella ictaluri infection. In this study, we cloned, sequenced using the RACE (rapid amplification of cDNA ends) method and cha...

  13. Evaluation of Catfish Skin Hydrolysates as a Glazing Material for Air-Blast Frozen Shrimp

    Science.gov (United States)

    Catfish is one of the most widely consumed seafood in the United States. A by-product of this consumption is a large quantity of catfish skin (CS), approximately 8,200 metric tons in 2014. Enzymatic hydrolysis is used to produce protein hydrolysates from the skin. These hydrolysates have considerabl...

  14. Performance evaluation of intensive, pond-based culture systems for catfish production in Mississippi: year one

    Science.gov (United States)

    Catfish farming is the leading form of aquaculture in the U.S. and has a significant economic impact in the southern states. Increased feed and energy costs, and competition from foreign imports have recently caused catfish farmers to intensify production as a means of improving efficiency and profi...

  15. Draft Genome Sequences of Four Virulent Aeromonas hydrophila Strains from Catfish Aquaculture

    Science.gov (United States)

    Tekedar, Hasan C.; Kumru, Salih; Karsi, Attila; Waldbieser, Geoffrey C.; Sonstegard, Tad; Schroeder, Steven G.; Liles, Mark R.; Griffin, Matt J.

    2016-01-01

    Since 2009, a clonal group of virulent Aeromonas hydrophila strains has been causing severe disease in the catfish aquaculture industry in the southeastern United States. Here, we report draft genomes of four A. hydrophila isolates from catfish aquaculture that represent this clonal group. PMID:27540076

  16. Draft genome sequences of four virulent aeromonas hydrophila strains from catfish aquaculture

    Science.gov (United States)

    Since 2009, a clonal group of virulent Aeromonas hydrophila (VAh) strains has been causing severe disease in the catfish aquaculture industry in the Southeastern United States. Here, we report draft genomes of four A. hydrophila isolates from catfish aquaculture that represent this clonal group....

  17. Celioscopic liver biopsy in silver catfish (Rhamdia quelen

    Directory of Open Access Journals (Sweden)

    João P.S. Feranti

    2015-01-01

    Full Text Available Endosurgery has been used for assessment of fish celomatic cavity, as well as for obtaining biopsies for organic analysis. Such minimally invasive access may also be used for the analysis of environmental impact on biomarkers of pollution. In Brazil, studies and literature regarding the use of celioscopy in fish are sparse. The purpose of the current study was to develop a two-port celioscopy technique to obtain liver biopsy in silver catfish (Rhamdia quelen. Six adult female silver catfish were used. The animals were anesthetized and the inspection of the celomatic cavity were performed using a telescope and celioscopic-guided liver biopsy were taken using laparoscopic Kelly forceps. On the early postoperative period, the animals were released in a confined water reservoir where mortality could be checked. The liver samples were sent for histological assessment. There were no complications during surgery on early postoperative period. It was possible to visualize meticulously several organs (liver, spleen, stomach, pancreas, swim bladder, ovaries, bowel and transverse septum. In conclusion, the surgical technique and the anesthetic protocol proposed were suitable to perform liver biopsies in silver catfish and provided low morbidity.

  18. The use of hematology method and blood endoparasite observation for determining catfish (Clarias gariepinus) health in fishery Mangkubumen, Boyolali

    OpenAIRE

    AGUNG BUDIHARJO; NOOR SOESANTI HANDAJANI; INTAN ESTETIKA ALAMANDA

    2007-01-01

    This research aims to find out the health condition of catfish (Clarias gariepinus) based on hematology and to find out the blood endoparasite type of catfish (Clarias gariepinus) bred in Mangkubumen Boyolali. The sample collection of catfish in this research was conducted in Mangkubumen, Boyolali. The catfish becoming the sample had following criteria: 3 month old, 100-150 gr weight, and 20-25 cm long. The sample of catfish was taked from 5 pools, it was taken 10 fishes from each pool. The ...

  19. DENMARK – EUROPEAN CHAMPION IN ORGANIC RAINBOW TROUT

    OpenAIRE

    Larsen, Erling P.; Nielsen, Max; Larsen, Villy J.; Jokumsen, Alfred

    2016-01-01

    In 2014 Denmark was the biggest producer of organic rainbow trout in Europe with a total amount of 1,080 tons. The producers of the organic trout had a better economic earning than the conventional producers, measured per unit produced. The value wason average 8 % higher per unit than for the conventional producers. The solvency ratio was in 2012 an average of 28 %, which was higher than the traditional trout producers’ solvency ratio (solvency ratio measure an enterprises ability to meet its...

  20. TROUT STEAKS: CONSUMER PERCEPTIONS OF A NEW FOOD ITEM

    OpenAIRE

    Dasgupta, Siddhartha; Foltz, John C.; Jacobsen, Bonnie

    2000-01-01

    Water quality standards and a limited water supply have dramatically restricted the expansion of the U.S. trout industry. Faced with production restrictions, producers have turned to value-added products to strengthen the economic growth of the industry. In the near future, trout steaks could surface in retail outlets as a new revenue source for the mature trout industry. A telephone survey of consumers in Chicago and Los Angeles was conducted by the University of Idaho in the spring of 1997 ...

  1. CONSUMER PERCEPTIONS OF TROUT AS A FOOD ITEM

    OpenAIRE

    Foltz, John C.; Dasgupta, Siddhartha; Devadoss, Stephen

    1999-01-01

    The impacts of socioeconomic/demographic characteristics, experiences and preferences of consumers on trout purchasing decisions were estimated using Probit and Ordered Probit regression techniques. Data from a survey of consumer purchasing behavior and personal attributes were used to deduce factors that led to either a high or low likelihood of purchasing trout products. Analysis of data pertaining to whole trout and value-added products yielded consistently different characteristics of con...

  2. Comparative analysis of catfish BAC end sequences with the zebrafish genome

    Directory of Open Access Journals (Sweden)

    Abernathy Jason

    2009-12-01

    Full Text Available Abstract Background Comparative mapping is a powerful tool to transfer genomic information from sequenced genomes to closely related species for which whole genome sequence data are not yet available. However, such an approach is still very limited in catfish, the most important aquaculture species in the United States. This project was initiated to generate additional BAC end sequences and demonstrate their applications in comparative mapping in catfish. Results We reported the generation of 43,000 BAC end sequences and their applications for comparative genome analysis in catfish. Using these and the additional 20,000 existing BAC end sequences as a resource along with linkage mapping and existing physical map, conserved syntenic regions were identified between the catfish and zebrafish genomes. A total of 10,943 catfish BAC end sequences (17.3% had significant BLAST hits to the zebrafish genome (cutoff value ≤ e-5, of which 3,221 were unique gene hits, providing a platform for comparative mapping based on locations of these genes in catfish and zebrafish. Genetic linkage mapping of microsatellites associated with contigs allowed identification of large conserved genomic segments and construction of super scaffolds. Conclusion BAC end sequences and their associated polymorphic markers are great resources for comparative genome analysis in catfish. Highly conserved chromosomal regions were identified to exist between catfish and zebrafish. However, it appears that the level of conservation at local genomic regions are high while a high level of chromosomal shuffling and rearrangements exist between catfish and zebrafish genomes. Orthologous regions established through comparative analysis should facilitate both structural and functional genome analysis in catfish.

  3. The economic value of trout fishery management programs

    International Nuclear Information System (INIS)

    The contingent valuation method is used to estimate the economic value of a trout fishing day at the Cache la Poudre River in Colorado. In addition, changes in daily economic value and yearly participation are estimated for changes in the quality of fishing such as: (1) change in catch or size of catch; (2) wild trout fishing versus hatchery trout fishing; (3) change in catch or size under catch and release management. Anglers are grouped by a distinguishing characteristic, skill level, and the economic value of trout fishing and changes in the quality of fishing are compared at different skill levels

  4. Blood cues induce antipredator behavior in Nile tilapia conspecifics.

    Directory of Open Access Journals (Sweden)

    Rodrigo Egydio Barreto

    Full Text Available In this study, we show that the fish Nile tilapia displays an antipredator response to chemical cues present in the blood of conspecifics. This is the first report of alarm response induced by blood-borne chemical cues in fish. There is a body of evidence showing that chemical cues from epidermal 'club' cells elicit an alarm reaction in fish. However, the chemical cues of these 'club' cells are restricted to certain species of fish. Thus, as a parsimonious explanation, we assume that an alarm response to blood cues is a generalized response among animals because it occurs in mammals, birds and protostomian animals. Moreover, our results suggest that researchers must use caution when studying chemically induced alarm reactions because it is difficult to separate club cell cues from traces of blood.

  5. Ventilation rates indicate stress-coping styles in Nile tilapia.

    Science.gov (United States)

    Barreto, Rodrigo E; Volpato, Gilson L

    2011-12-01

    Behavioural responses to stress can form distinct profiles in a wide range of animals: proactive and reactive profiles or coping styles. Stress responsiveness can also differentiate between the behavioural profiles. The tendency to regain feed intake following transfer to a novel social-isolation tank (the speed of acclimation) can discriminate between proactive or reactive profiles. Consequently, differential stress responsiveness can be linked to this feeding behaviour trait. This study shows that ventilation rates of Nile tilapia, Oreochromis niloticus (L.), correlate with the rate of feeding resumption, following transfer to a novel social-isolation aquarium. Therefore, ventilation rate (VR) indicates coping styles; consequently, VR is a proxy for the way fish will deal with environmental challenges. PMID:22116283

  6. Ventilation rates indicate stress-coping styles in Nile tilapia

    Indian Academy of Sciences (India)

    Rodrigo E Barreto; Gilson L Volpato

    2011-12-01

    Behavioural responses to stress can form distinct profiles in a wide range of animals: proactive and reactive profiles or coping styles. Stress responsiveness can also differentiate between the behavioural profiles. The tendency to regain feed intake following transfer to a novel social-isolation tank (the speed of acclimation) can discriminate between proactive or reactive profiles. Consequently, differential stress responsiveness can be linked to this feeding behaviour trait. This study shows that ventilation rates of Nile tilapia, Oreochromis niloticus (L.), correlate with the rate of feeding resumption, following transfer to a novel social-isolation aquarium. Therefore, ventilation rate (VR) indicates coping styles; consequently, VR is a proxy for the way fish will deal with environmental challenges.

  7. Landscape-scale evaluation of asymmetric interactions between Brown Trout and Brook Trout using two-species occupancy models

    Science.gov (United States)

    Wagner, Tyler; Jefferson T. Deweber; Jason Detar; John A. Sweka

    2013-01-01

    Predicting the distribution of native stream fishes is fundamental to the management and conservation of many species. Modeling species distributions often consists of quantifying relationships between species occurrence and abundance data at known locations with environmental data at those locations. However, it is well documented that native stream fish distributions can be altered as a result of asymmetric interactions between dominant exotic and subordinate native species. For example, the naturalized exotic Brown Trout Salmo trutta has been identified as a threat to native Brook Trout Salvelinus fontinalis in the eastern United States. To evaluate large-scale patterns of co-occurrence and to quantify the potential effects of Brown Trout presence on Brook Trout occupancy, we used data from 624 stream sites to fit two-species occupancy models. These models assumed that asymmetric interactions occurred between the two species. In addition, we examined natural and anthropogenic landscape characteristics we hypothesized would be important predictors of occurrence of both species. Estimated occupancy for Brook Trout, from a co-occurrence model with no landscape covariates, at sites with Brown Trout present was substantially lower than sites where Brown Trout were absent. We also observed opposing patterns for Brook and Brown Trout occurrence in relation to percentage forest, impervious surface, and agriculture within the network catchment. Our results are consistent with other studies and suggest that alterations to the landscape, and specifically the transition from a forested catchment to one that contains impervious surface or agriculture, reduces the occurrence probability of wild Brook Trout. Our results, however, also suggest that the presence of Brown Trout results in lower occurrence probability of Brook Trout over a range of anthropogenic landscape characteristics, compared with streams where Brown Trout were absent.

  8. Supplemental effects of mixed ingredients and rice bran on the growth performance, survival and yield of Nile tilapia, Oreochromis niloticus reared in fertilized earthen ponds.

    Science.gov (United States)

    Limbu, S M; Shoko, A P; Lamtane, H A; Kishe-Machumu, M A; Joram, M C; Mbonde, A S; Mgana, H F; Mgaya, Y D

    2016-01-01

    Unaffordability of commercial feeds to semi-intensive Nile tilapia, Oreochromis niloticus farmers has led to reliance on supplemental feeding and fertilization for nutrition of their fish without a scientific basis. This study compared the growth, survival, condition factor and yield performance of O. niloticus fed on mixed ingredients (MI) and rice bran alone (RB) diets reared in fertilized earthen ponds in small scale farmers' ponds. The study also determined phytoplankton composition, biomass and abundance in the experimental ponds. Quadruplicate ponds were stocked with O. niloticus and African sharptooth catfish, Clarias gariepinus at a stocking ratio of 1:3. The initial mean weights of O. niloticus and C. gariepinus were 14.62 ± 0.61 and 20.34 ± 1.44 g respectively. The fish were fed on MI and RB diets with protein content of 184.74 and 126.06 g kg(-1) respectively for 270 days. The results showed that growth performance, survival rate and condition factor of O. niloticus were not affected by either feeding with MI or RB diet (p > 0.05). Moreover, there were no significant differences obtained in phytoplankton biomass and abundance in O. niloticus ponds fed on the two diets (p > 0.05). Furthermore, feeding O. niloticus either on MI or RB diet did not affect the net and gross fish yields (p > 0.05). The study revealed that the use of either MI or RB diet does not significantly affect the performance of O. niloticus cultured in semi-intensive earthen ponds where natural food organisms are an integral part of the culture system. Rice bran could be used for semi-intensive culture of O. niloticus in fertilized ponds to boost the production based on its availability and low cost. PMID:26759744

  9. 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.

  10. BIOLOG MICROLOG® IDENTIFICATION OF Lactococcus garvieae INFECTION IN NILE TILAPIA Oreochromis niloticus AND PINTADO Pseudoplathystoma corruscans FROM BRAZIL

    Science.gov (United States)

    Lactococcus garvieae infection in cultured Nile tilapia, Oreochromis niloticus, and pintado, Pseudoplathystoma corruscans from Brazil is reported. This is the first evidence of the presence of this pathogen from Brazilian fish and the first report of L. garvieae infection in either Nile tilapia or ...

  11. Growth Response and Acquired Resistance of Nile Tilapia Oreochromis niloticus Following Infection or Vaccination with Streptococcus iniae

    Science.gov (United States)

    Growth performance and acquired resistance of Nile tilapia, Oreochromis niloticus (L.) that survived Streptococcus iniae infection was determined. Tilapia were challenged with three doses of S. iniae (8.8 x 10 to the 3rd power, 8.8 x 10 to the 4th power and 8.8 x 10 to the 5th power CFU fish-1 for ...

  12. Growth response and acquired resistance of Nile tilapia Orechromis niloticus following infection or vaccination with Streptococcus iniae.

    Science.gov (United States)

    Growth performance and acquired resistance of Nile tilapia, Oreochromis niloticus that survived Streptococcus iniae infection was determined. Tilapia were challenged with three doses of S. iniae (8.8 x 10 to the third power, 8.8 x 10 to the fourth power and 8.8 x 10 to the fifth power CFU fish-1 f...

  13. Identification and transcriptional profile of multiple genes in the posterior kidney of Nile tilapia at 6h post bacterial infections

    Science.gov (United States)

    To understand the molecular mechanisms involved in response of Nile tilapia (Oreochromis niloticus) to bacterial infection, suppression subtractive cDNA hybridization technique was used to identify upregulated genes in the posterior kidney of Nile tilapia at 6h post infection with Aeromonas hydrophi...

  14. Controlled challenge experiment demonstrates substantial additive genetic variation in resistance of Nile tilapia (Oreochromis niloticus) to Streptococcus iniae

    Science.gov (United States)

    Streptococcus iniae is an etiologic agent of streptococcal disease in tilapia and is one of several Streptococcus spp. that negatively impact worldwide tilapia production. Methods for the prevention and control of S. iniae include vaccines, management strategies, and antibiotics. A complimentary pre...

  15. Do native brown trout and non-native brook trout interact reproductively?

    Science.gov (United States)

    Cucherousset, J.; Aymes, J. C.; Poulet, N.; Santoul, F.; Céréghino, R.

    2008-07-01

    Reproductive interactions between native and non-native species of fish have received little attention compared to other types of interactions such as predation or competition for food and habitat. We studied the reproductive interactions between non-native brook trout ( Salvelinus fontinalis) and native brown trout ( Salmo trutta) in a Pyrenees Mountain stream (SW France). We found evidence of significant interspecific interactions owing to consistent spatial and temporal overlap in redd localizations and spawning periods. We observed mixed spawning groups composed of the two species, interspecific subordinate males, and presence of natural hybrids (tiger trout). These reproductive interactions could be detrimental to the reproduction success of both species. Our study shows that non-native species might have detrimental effects on native species via subtle hybridization behavior.

  16. Factors influencing brown trout reproductive success in Ozark tailwater rivers

    Science.gov (United States)

    Pender, D.R.; Kwak, T.J.

    2002-01-01

    The reproductive success of brown trout Salmo trutta in White River, Arkansas, tailwater reaches is highly variable, resulting in the need for supplemental stocking. A better understanding of the physical and biotic factors affecting reproduction and survival would enhance the contribution of wild fish. We compared fecundity, reproductive chronology, physical habitat, water quality, trout density, food availability, diet, predation, and competitive interactions among four tailwater reaches to identify factors influencing brown trout reproductive success. The fecundity and condition factor of prespawning brown trout were significantly lower at Beaver Tailwater, a reach known for reproductive failure, than at other sites, among which no differences were found. Brown trout spawning was observed from 11 October to 23 November 1996, and juvenile emergence began on 28 February 1997. Significant among-site differences were detected for spawning and juvenile microhabitat variables, but the variables fell within or near suitable or optimal ranges reported in the literature for this species. Age-0 brown trout density differed significantly among sites, but growth and condition did not. Predation by Ozark sculpin Cottus hypselurus on trout eggs or age-0 trout of any species was not observed among the 418 stomachs examined. Ozark sculpin density and diet overlap with age-0 brown trout were highest and invertebrate food availability and water fertility were lowest at Beaver Tailwater relative to the other reaches. Our findings indicate that differences in trophic conditions occur among tailwater reaches, and a lower system productive capacity was identified at Beaver Tailwater. We suggest that management efforts include refining the multispecies trout stocking regime to improve production efficiency, enhancing flow regulation, and increasing habitat complexity to increase invertebrate and fish productivity. Such efforts may lead to improved natural reproduction and the

  17. Modelling Waste Output from Trout Farms

    DEFF Research Database (Denmark)

    Frier, J. O.; From, J.; Larsen, Torben;

    1995-01-01

    The aim of waste modelling in aquaculture is to provide tools for simulating input, transformation, output and subsidiary degradation in recipients of organic compounds, nitrogen, and phosphorus. The direct purpose of this modelling is to make it possible for caretakers and water authorities to...... lacking. Within trout farming this work attempts to establish the different submodels and outlines future possibilities for synthesizing the knowledge to a numerical model....

  18. Brook trout passage performance through culverts

    Science.gov (United States)

    Goerig, Elsa; Castro-Santos, Theodore R.; Bergeron, Normand

    2016-01-01

    Culverts can restrict access to habitat for stream-dwelling fishes. We used passive integrated transponder telemetry to quantify passage performance of >1000 wild brook trout (Salvelinus fontinalis) attempting to pass 13 culverts in Quebec under a range of hydraulic and environmental conditions. Several variables influenced passage success, including complex interactions between physiology and behavior, hydraulics, and structural characteristics. The probability of successful passage was greater through corrugated metal culverts than through smooth ones, particularly among smaller fish. Trout were also more likely to pass at warmer temperatures, but this effect diminished above 15 °C. Passage was impeded at higher flows, through culverts with steep slopes, and those with deep downstream pools. This study provides insight on factors influencing brook trout capacity to pass culverts as well as a model to estimate passage success under various conditions, with an improved resolution and accuracy over existing approaches. It also presents methods that could be used to investigate passage success of other species, with implications for connectivity of the riverscape.

  19. Estrogenic effects of phytoestrogens in brown trout (Salmo trutta)

    DEFF Research Database (Denmark)

    Nielsen, Louise Marie; Holbech, Henrik; Bjerregaard, Poul;

    2010-01-01

    , the potential effect of the waterborne phytoestrogens on endemic fish species is largely unknown. In the present investigation, the estrogenic effect of biochanin A was tested in brown trout through water exposure experiments. Juvenile brown trout of both sexes were exposed to different concentrations...

  20. SuchThatCast Episode 3: J.D. Trout

    NARCIS (Netherlands)

    Søraker, J.H.

    2012-01-01

    SuchThatCast goes mobile in the third episode, as I interview J.D. Trout on the appr. 2 hour train ride between Enschede and Schiphol airport. Trout received his PhD in Philosophy at Cornell University and is currently Professor of Philosophy and Psychology at Loyola University Chicago. He was recen

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

    DEFF Research Database (Denmark)

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

    2011-01-01

    The fish pathogen Flavobacterium psychrophilum is one of the main causes of mortality in fry of farmed rainbow trout (Oncorhynchus mykiss) and other salmonid fish. The disease following infection is often called bacterial coldwater disease (BCWD) in USA and rainbow trout fry syndrome (RTFS) in...

  2. The Effects of Acute Stress on Rainbow Trout (Oncorhynchus mykiss)

    OpenAIRE

    KUBİLAY, Ayşegül

    2002-01-01

    The physiological effects of acute stressors (transport, handling, netting and confinement) on rainbow trout in an aquaculture system were investigated. Serum cortisol level, serum glucose and lysozyme activity were determined in rainbow trout stressed by acute stressors, and compared with those of unstressed (control) fish. Serum cortisol, glucose levels and lysozyme activity were significantly higher(P

  3. Some Direct Gillnet Selectivity Tests for Brown Trout Populations

    OpenAIRE

    O Grady, M. F.

    1981-01-01

    Direct gillnet selectivity tests for introduced brown trout populations in three Irish lakes are outlined. The net gangs and netting procedure utilised are described. Data indicates that the gear used was capable of capturing a random cross section of a trout stock in the length frequency range 19.8 to 47.7 centimetres.

  4. Effect of ionising radiation on Tilapia protein biofilms

    International Nuclear Information System (INIS)

    practiced in developing country, in special myofibril proteins from fish cultured in captivity. Besides Tilapia (Tilapia-do-nilo) present a fast grow e good handling that represents interesting productivity. The mechanical and barrier properties of protein-based films are generally better than those of polysaccharide-based films. This is due to the fact that, contrary to polysaccharides which are homopolymers, proteins have a specific structure (based on 20 different monomers) which confers a wider range of potential functional properties, specially high intermolecular binding potential. Besides myofibril protein from Tilapia has 3.43% (aminoacid: protein) of tyrosine, a potential crosslinking site under radiation process. The aim of this paper was to study the effect of ionizing radiation on biofilms made from Tilapia myofibril proteins. The biofilms were prepared according a casting technique that consists in drying the forming film solution. The forming film solution was prepared from lyophilized myofibril protein in 1% protein concentration and two levels of plasticizer: 25% and 45% glycerol. The pH was 2,7 and the solution was heated at 40 deg. C during 30 minutes. The films were irradiated in electron accelerator type Radiation Dynamics, Inc., 1978, 1.5 MeV at dose range from 0 kGy to 200 kGy. Routine dosimeter was Cellulose Triacetate - CTA, Fuji Photo Film Co., Tokyo, Japan. The samples were kept at 25 deg. C and 58% relative moisture until the analysis. The main properties studied were color, opacity, solubility, and mechanical properties. Radiation did not affect significantly the parameters core and opacity (p<0.05) while glycerol level presented a changed in both parameters. Solubility increased in function of plasticizer level as biofilms containing 45% glycerol showed major values. The least value of solubility was obtained for 25% glycerol biofilms at dose 150 kGy and 200 kGy. The tensile strength at break showed an increase as the irradiation dose increases

  5. Otter ( Lutra lutra ) predation on stocked brown trout ( Salmo trutta ) in two Danish lowland rivers

    DEFF Research Database (Denmark)

    Jacobsen, Lene

    2005-01-01

    This study aimed to evaluate otter predation on stocked trout. Large hatchery-reared trout (16-30 cm) were stocked into two Danish rivers with different fish populations. Otter diet before and after trout stocking was determined by analysing 685 spraints, collected regularly during the 35-day study...... period. Fish composition in the rivers before stocking was assessed by electrofishing. In River Trend, a typical trout river, the proportion of trout in the otter diet increased from 8% before stocking to 33% a few days after stocking. Moreover, trout lengths in the diet changed significantly towards the...... lengths of stocked trout, indicating that newly stocked trout were preferred to wild trout. In River Skals, dominated by cyprinids, there was no change in otter diet after stocking of hatchery trout, i.e., these were ignored by otter. Otter predation should be taken into account together with fish and...

  6. Status of Oregon's Bull Trout.

    Energy Technology Data Exchange (ETDEWEB)

    Buchanan, David V.; Hanson, Mary L.; Hooton, Robert M.

    1997-10-01

    Limited historical references indicate that bull trout Salvelinus confluentus in Oregon were once widely spread throughout at least 12 basins in the Klamath River and Columbia River systems. No bull trout have been observed in Oregon's coastal systems. A total of 69 bull trout populations in 12 basins are currently identified in Oregon. A comparison of the 1991 bull trout status (Ratliff and Howell 1992) to the revised 1996 status found that 7 populations were newly discovered and 1 population showed a positive or upgraded status while 22 populations showed a negative or downgraded status. The general downgrading of 32% of Oregon's bull trout populations appears largely due to increased survey efforts and increased survey accuracy rather than reduced numbers or distribution. However, three populations in the upper Klamath Basin, two in the Walla Walla Basin, and one in the Willamette Basin showed decreases in estimated population abundance or distribution.

  7. The Effect of Addition Vitamin E on Catfish Oil Stability

    OpenAIRE

    Clara M. Kusharto; Mia Srimiati; Ikeu Tanziha; Sugeng heri Suseno

    2015-01-01

    Unsaturated fatty acids contained oils which sensitive to oxidation caused by heat, light and oxygen. The oxidized oil known harmful to the body. One of the effort to prevent the oxidation process is by adding antioxidants stability of oil catfish and shelf life of the oil. The experimental study was applied by adding vitamin E to the oil as much as 0.67 mg / g PUFA compared with the control oil. Oil was stored with the Schaal Oven Test method, which are stored at a temperature ...

  8. EFFECT OF FLUCTUATING EXPOSURES ON THE ACUTE TOXICITY OF AMMONIA TO RAINBOW TROUT (SALMO GAIRDNERI) AND CUTTHROAT TROUT (S. CLARKI)

    Science.gov (United States)

    Acute toxicity bioassays in which fish were exposed to short-term cyclic fluctuations of ammonia were conducted on rainbow trout (Salmo gairdneri) and on cutthroat trout (S. clarki). Companion tests were also conducted in which test fish were subjected to ammonia at constant conc...

  9. 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.

  10. Metals-contaminated benthic invertebrates in the Clark Fork River, Montana: Effects on age-0 brown trout and rainbow trout

    Science.gov (United States)

    Woodward, Daniel F.; Farag, Aïda M.; Bergman, Harold L.; Delonay, Aaron J.; Little, Edward E.; Smiths, Charlie E.; Barrows, Frederic T.

    1995-01-01

    Benthic organisms in the upper Clark Fork River have recently been implicated as a dietary source of metals that may be a chronic problem for young-of-the-year rainbow trout (Oncorhynchus mykiss). In this present study, early life stage brown trout (Salmo trutta) and rainbow trout were exposed for 88 d to simulated Clark Fork River water and a diet of benthic invertebrates collected from the river. These exposures resulted in reduced growth and elevated levels of metals in the whole body of both species. Concentrations of As, Cd, Cu, and Pb increased in whole brown trout; in rainbow trout, As and Cd increased in whole fish, and As also increased in liver. Brown trout on the metals-contaminated diets exhibited constipation, gut impaction, increased cell membrane damage (lipid peroxidation), decreased digestive enzyme production (zymogen), and a sloughing of intestinal mucosal epithelial cells. Rainbow trout fed the contaminated diets exhibited constipation and reduced feeding activity. We believe that the reduced standing crop of trout in the Clark Fork River results partly from chronic effects of metals contamination in benthic invertebrates that are important as food for young-of-the-year fish.

  11. Admixture analysis of stocked brown trout populations using mapped microsatellite DNA markers: indigenous trout persist in introgressed populations

    DEFF Research Database (Denmark)

    Hansen, Michael Møller; Mensberg, Karen-Lise Dons

    2009-01-01

    , but resolution is low if genetic differentiation is weak. Here, we analyse stocked brown trout populations represented by historical (1943-1956) and contemporary (2000s) samples, where genetic differentiation between wild populations and stocked trout is weak (pair-wise F-ST of 0.047 and 0.053). By...

  12. FOOD AND FEEDING HABITS OF TILAPIA ZILLI (PISCES: CICHLIDAE IN RIVER OTAMIRI SOUTH-EASTERN NIGERIA

    Directory of Open Access Journals (Sweden)

    Agbabiaka L. A.

    2012-06-01

    Full Text Available Dietary habits of Tilapia zilli (Gervais, 1848 was studied in River Otamiri, Imo State, Nigeria. Fish specimens were procured from Artisanal fishermen every two weeks. Specimens were usually injected 4% formalin at the fishing station prior to laboratory analysis. A total of 97 specimens were analyzed for gut contents using Numerical and frequency of occurrence methods. Data collected showed that Tilapia zilli is an Omnivorous fish with dietary preference for Algae (71.05% and 59.52%, vegetative matter (10.52% and 50.00%, detritus (0% and 11.90% and aquatic invertebrates larvae such as Chaoborus larvae (52.63% and 47.61% and Chironomid larvae (31.58% and 21.43% for juveniles and adult Tilapia respectively.

  13. Application of Highly Purified Electrolyzed Chlorine Dioxide for Tilapia Fillet Disinfection

    OpenAIRE

    2014-01-01

    This research aimed to develop an electrolysis method to generate high-concentration chlorine dioxide (ClO2) for tilapia fillet disinfection. The designed generator produced up to 3500 ppm of ClO2 at up to 99% purity. Tilapia fillets were soaked in a 400 ppm ClO2 solution for 5, 10, and 25 min. Results show that total plate counts of tilapia, respectively, decreased by 5.72 to 3.23, 2.10, and 1.09 log CFU/g. In addition, a 200 ppm ClO2 solution eliminated coliform bacteria and Escherichia col...

  14. Chemometrics applied to the incorporation of omega-3 in tilapia fillet feed flaxseed flour

    Directory of Open Access Journals (Sweden)

    Márcia Fernandes Nishiyama

    2014-09-01

    Full Text Available This study evaluated the effect of adding flaxseed flour to the diet of Nile tilapia on the fatty acid composition of fillets using chemometrics. A traditional and an experimental diet containing flaxseed flour were used to feed the fish for 60 days. An increase of 18:3 n-3 and 22:6 n-3 and a decrease of 18:2 n-6 were observed in the tilapia fillets fed the experimental diet. There was a reduction in the n-6:n-3 ratio. A period of 45 days of incorporation caused a significant change in tilapia chemical composition. Principal Component Analysis showed that the time periods of 45 and 60 days positively contributed to the total content of n-3, LNA, and DHA, highlighting the effect of omega-3 incorporation in the treatment containing flaxseed flour.

  15. APPARENT DIGESTIBILTY EXPERIMENT WITH NILE TILAPIA (OREOCHROMIS NILOTICUS FED DIETS CONTAINING CITRULLUS LANATUS SEEDMEAL

    Directory of Open Access Journals (Sweden)

    Wasiu Adeyemi JIMOH

    2015-12-01

    Full Text Available Apparent digestibility coefficients of nutrients in Citrullus lanatus based diets were determined for Nile tilapia (Oreochromis niloticus using AIA as marker or indicator. 150 tilapia fingerlings of average weight 6.12±0.05g were acclimatized for a week, weighed and allotted into five dietary treatments; CTR, DT2, DT3, DT4 and DT5 containing 0, 15, 30, 45 and 60% Citrullus lanatus respectively. The diets were isonitrogenous, isocaloric and isolipidic. Each treatment was replicated three times with ten fish per replicate. Fish were fed 5% body weight on two equal proportions per day. The results from the study indicated that there was no significant variation (p>0.05 in the apparent organic matter and gross energy digestibility coefficients of the diets; that there was significant (p0.05 in the apparent digestibility coefficients of nutrients (protein, energy, lipid and carbohydrates between the diets up to 30% replacement levels for tilapia.

  16. Shelf life and sensory assessment of tilapia quenelle during frozen storage

    Directory of Open Access Journals (Sweden)

    Maria Fernanda Calil Angelini

    2013-08-01

    Full Text Available The objective of this work was to evaluate the shelf life and sensory attributes of tilapia quenelle. Treatments consisted of two types of packages - polyethylene zipper (retort pouch (QA and polyethylene waxed paper box (QB - stored at -18ºC for 120 days. Tilapia quenelle was stable for all parameters established by Brazilian legislation. Average values of the evaluated attributes in different packages, during storage, showed no significant difference, except for the "refrigeration" flavor. However, during the storage period, there were significant differences for sensory attributes, as "moist appearance", fish and product aroma, and off flavors of "mud" and "refrigeration". Preserving product quality as for its sensory attributes, during storage, shows that tilapia quenelle is a convenience product and contributes to the increase of fish consumption.

  17. Extraction and characterization of gelatin biopolymer from black tilapia (Oreochromis mossambicus) scales

    Science.gov (United States)

    Sockalingam, K.; Abdullah, H. Z.

    2015-07-01

    Black tilapia (Oreochromis mossambicus) fish wastes (scales) were evaluated for its suitability as sources of gelatin. Scales were subjected to acid treatment for demineralization before it undergoes thermal extraction process. The raw scales were characterized via Scanning Electron Microscopy (SEM), which demarcated the cycloid pattern of the scales. SEM images also reveal the presence of collagen fiber in the fish scale. The black tilapia fish scales yields 11.88 % of gelatin, indicating the possibility of this fish species as sources of gelatin. Further characterizations were done on both raw scale and extracted gelatin through Fourier Transform Infrared Spectroscopy (FTIR) and proximate analysis. The scale gelatin shows high protein content (86.9 %) with low moisture (8.2 %) and ash (1.4 %). This further proves the effectiveness of the demineralization and extraction method used. The black tilapia fish scale is found to be a prospective source of gelatin with good chemical and functional properties.

  18. Extraction and characterization of gelatin biopolymer from black tilapia (Oreochromis mossambicus) scales

    Energy Technology Data Exchange (ETDEWEB)

    Sockalingam, K., E-mail: gd130106@siswa.uthm.edu.my; Abdullah, H. Z., E-mail: hasan@uthm.edu.my [Faculty of Mechanical and Manufacturing Engineering, Universiti Tun Hussein Onn Malaysia, 86400 Parit Raja, Batu Pahat, Johor (Malaysia)

    2015-07-22

    Black tilapia (Oreochromis mossambicus) fish wastes (scales) were evaluated for its suitability as sources of gelatin. Scales were subjected to acid treatment for demineralization before it undergoes thermal extraction process. The raw scales were characterized via Scanning Electron Microscopy (SEM), which demarcated the cycloid pattern of the scales. SEM images also reveal the presence of collagen fiber in the fish scale. The black tilapia fish scales yields 11.88 % of gelatin, indicating the possibility of this fish species as sources of gelatin. Further characterizations were done on both raw scale and extracted gelatin through Fourier Transform Infrared Spectroscopy (FTIR) and proximate analysis. The scale gelatin shows high protein content (86.9 %) with low moisture (8.2 %) and ash (1.4 %). This further proves the effectiveness of the demineralization and extraction method used. The black tilapia fish scale is found to be a prospective source of gelatin with good chemical and functional properties.

  19. Extraction and characterization of gelatin biopolymer from black tilapia (Oreochromis mossambicus) scales

    International Nuclear Information System (INIS)

    Black tilapia (Oreochromis mossambicus) fish wastes (scales) were evaluated for its suitability as sources of gelatin. Scales were subjected to acid treatment for demineralization before it undergoes thermal extraction process. The raw scales were characterized via Scanning Electron Microscopy (SEM), which demarcated the cycloid pattern of the scales. SEM images also reveal the presence of collagen fiber in the fish scale. The black tilapia fish scales yields 11.88 % of gelatin, indicating the possibility of this fish species as sources of gelatin. Further characterizations were done on both raw scale and extracted gelatin through Fourier Transform Infrared Spectroscopy (FTIR) and proximate analysis. The scale gelatin shows high protein content (86.9 %) with low moisture (8.2 %) and ash (1.4 %). This further proves the effectiveness of the demineralization and extraction method used. The black tilapia fish scale is found to be a prospective source of gelatin with good chemical and functional properties

  20. Growth rate differences between resident native brook trout and non-native brown trout

    Science.gov (United States)

    Carlson, S.M.; Hendry, A.P.; Letcher, B.H.

    2007-01-01

    Between species and across season variation in growth was examined by tagging and recapturing individual brook trout Salvelinus fontinalis and brown trout Salmo trutta across seasons in a small stream (West Brook, Massachusetts, U.S.A.). Detailed information on body size and growth are presented to (1) test whether the two species differed in growth within seasons and (2) characterize the seasonal growth patterns for two age classes of each species. Growth differed between species in nearly half of the season- and age-specific comparisons. When growth differed, non-native brown trout grew faster than native brook trout in all but one comparison. Moreover, species differences were most pronounced when overall growth was high during the spring and early summer. These growth differences resulted in size asymmetries that were sustained over the duration of the study. A literature survey also indicated that non-native salmonids typically grow faster than native salmonids when the two occur in sympatry. Taken together, these results suggest that differences in growth are not uncommon for coexisting native and non-native salmonids. ?? 2007 The Authors.

  1. 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.

  2. Acclimatization test of Nile tilapia Oreochromis niloticus in Lebna reservoir (Cap Bon, Tunisia)

    OpenAIRE

    Derouiche, E.; Azaza, M.S; KRAIEM M. M.

    2009-01-01

    Ce travail consiste à tester l’acclimatation d’une espèce thermophile, le tilapia du Nil Oreochromis niloticus dans la retenue du barrage Lebna (Cap Bon), moyennant un système extensif de grossissement. Les résultats montrent que le tilapia introduit directement en pleine retenue a pu se maintenir et supporter les mauvaises conditions hivernales en adoptant une stratégie d’hibernation. Par ailleurs, avec le retour des conditions favorables (T>20°C), ce Cichlidé a montré une bonne condition, u...

  3. Masculinization of red tilapia Oreochromis SPP. With steroid trenbolone acetate (TBA) provided in the food

    OpenAIRE

    Apolinar Santamaría Miranda; Jesús Humberto Heredía Bacasegua; Juan Pablo Apún Molina; Martín Armando Román Vega; Luis Daniel García Rodríguez; José Ángel Trigueros Salmerón

    2012-01-01

    The tilapia culture in our country has presented in recent years a significant rise and diversification, this due to the food shortage in our country and in the rest of the world, there are some alternatives to increase the profitability of their crop and is also an activity important in the state of Sinaloa, mainly in the communities adjacent to the dams and reservoirs of water. Inthe present study we present the results obtained in the process of sex reversal of red tilapia fingerlings Oreo...

  4. Effect of isoproteinous feed on growth and survival of tilapia (Oreochromis niloticus) fry

    OpenAIRE

    Siddika, I.; Das, M.; Sumi, K.R.

    2012-01-01

    A four week experiment was conducted to evaluate the effect of isoproteinous (35%) feed prepared named diet 1, 2, 3 and 4 respectively by substituting 0%, 50% , 75% and 100% fish meal with meat and bone meal in view of preparing a cost effective tilapia (Oreochromis niloticus) fry feed. The four experimental diets (diet 1 to 4) each were randomly assigned to twelve hapas with three replications. Tilapia fry (0.011g) were randomly stocked in 100 fry/9ft² hapa and fed five times a day up to the...

  5. Developmental Biology of the Supermale YY Tilapia (Oreochromis niloticus): Histogenesis of the Reproductive System

    OpenAIRE

    Annabelle Herrera; Rinella Cruz

    2001-01-01

    Histogenesis of the reproductive system of supermale (YY) tilapia and XY tilapia reared at the Central Luzon State University was analyzed with the use of paraffin sections. In the course of development, the primordial germ cells appeared at the same age in YY and XY males, i.e., at 8 days posthatch. These cells which were larger in the YY (1.85 µm) than in the XY male (0.9 µm) later established themselves in the gonadal anlage by days 9-22. The lobules appeared earlier in the YY at day 15. B...

  6. Radioactivity studies on farm raised and wild catfish produced in Mississippi, USA

    International Nuclear Information System (INIS)

    To understand the contribution of radiation dose to human from consumption of catfish, a comparative radiological assessment study was performed on farm and river raised fish. Gamma spectroscopic analyses of catfish indicated the presence of isotopes of 40K, 226Ra, and 228Ra with activity values of 99.4 ± 14.5, 0.41 ± 0.05, and 0.89 ± 0.08 Bq kg-1 respectively in farm catfish and 101 ± 15.7, 0.47 ± 0.05, and 0.97 ± 0.050 Bq kg-1 respectively in river catfish. The measured activities in two sets of samples were statistically compared using a two-tailed t test at 95 % confidence interval and results indicated that activities of 226Ra and 228Ra were significantly different. (author)

  7. Short-term feed deprivation alters immune status of surface mucosa in channel catfish (Ictalurus punctatus)

    Science.gov (United States)

    Short-term feed deprivation (or fasting) is a common occurrence in aquacultured fish species whether due to season, production strategies, or disease. In channel catfish (Ictalurus punctatus) fasting impacts susceptibility to several bacterial pathogens including Flavobacterium columnare, the causat...

  8. The fry patterns in the South-American catfish genus Corydoras (Pisces, Siluriformes, Callichthyidae)

    OpenAIRE

    Fuller, Ian

    1999-01-01

    The fry pattern of aquarium-bred species of the South-American catfish genus Corydoras, contribute to discriminate between species of the so-called ‘acutus’-group, showing a greyish adult colour pattern.

  9. Effect of Microwave Pretreatment on Extraction Yield and Quality of Catfish Oil in Northern Thailand

    Directory of Open Access Journals (Sweden)

    Chimsook Thitiphan

    2015-01-01

    Full Text Available The effect of microwave pretreatment of catfish processing waste on oil recovery and quality was investigated. Fish oil was extracted using the enzymatic hydrolysis using alcalase enzyme after the microwave pretreatment. The effect of microwave power and microwave pretreatment times was evaluated. The results revealed that a highest yield of 9.25% when catfish waste was treated at 110 W for 60 s. This condition was found as the most appropriate condition of microwave pretreatment since it decreased the extraction time from 150 min to up to 30 min. Analysis of oil quality indices (e.g. acid value, p-anisidine value, peroxide value extracted by microwave pretreatment and non-pretreatment indicated that catfish oil from both processes has comparatively similar fatty acids composition. In addition, catfish oil was extracted by microwave pretreatment and enzymatic hydrolysis had lower lipid oxidation compared to several standards.

  10. Chronic pathology and longevity of Drepanocephalus spathans infections in juvenile channel catfish

    Science.gov (United States)

    Drepanocephalus spathans (Digenea: Echinostomatidae) is a common parasite of the double-crested cormorant (Phalacrocorax auritus). The cercariae of D. spathans have been shown infective to juvenile channel catfish (Ictalurus punctatus). The developing metacercariae concentrate in the cranial regio...

  11. Disposition of 1-naphthol in the channel catfish

    International Nuclear Information System (INIS)

    Limited data exists on the disposition of xenobiotics in the channel catfish. The present study examines 1-naphthol as a model compound for phase 2 metabolism and dose dependent kinetics in this species. 14C-Naphthol was administered orally or intravascularly at 1, 5 or 25 mg/kg. Plasma levels of naphthol after intravascular dosing were fitted to a three compartment pharmacokinetic model. There was a dose related change in several pharmacokinetic parameters but little evidence of metabolic saturation. Approximately 60% of the oral dose was renally excreted in 24 hr as glucuronide and sulfate conjugates. The bile also contained the glucuronide and an unidentified polar metabolite, but little or no sulfate. The low bioavailability (38%) of naphthol was probably a result of first pass metabolism. The edible flesh had the lowest levels of residual compound while the liver and trunk kidney had the highest. Approximately 1% of the dose remained in the tissues at 24 hr. This study demonstrates that 1-naphthol is readily conjugated and rapidly eliminated in catfish. The dose dependency of kinetic values may have resulted from saturable tissue binding

  12. An Asian Origin of Virulent Aeromonas hydrophila Responsible for Disease Epidemics in United States-Farmed Catfish

    OpenAIRE

    Hossain, Mohammad J.; Sun, Dawei; McGarey, Donald J.; Wrenn, Shannon; Alexander, Laura M.; Martino, Maria Elena; Xing, Ye; Terhune, Jeffery S.; Liles, Mark R.

    2014-01-01

    ABSTRACT Since 2009, catfish farming in the southeastern United States has been severely impacted by a highly virulent and clonal population of Aeromonas hydrophila causing motile Aeromonas septicemia (MAS) in catfish. The possible origin of this newly emerged highly virulent A. hydrophila strain is unknown. In this study, we show using whole-genome sequencing and comparative genomics that A. hydrophila isolates from diseased grass carp in China and catfish in the United States have highly si...

  13. Rainbow Trout Haematology Coinciding with Metabolic Requirement

    Directory of Open Access Journals (Sweden)

    Ghulam Nabi LONE

    2012-12-01

    Full Text Available Rainbow trout (Onchorhynchus mykiss are an important aquaculture species yet there are few diagnostic tools available to assess their health. There is little published information regarding age-related changes in blood values of juvenile fish. It is important to evaluate juvenile fish, as this is the time they are raised in aquaculture settings. Determining age-related changes in the blood values of fishes would further develop clinical pathology as a diagnostic tool, enhancing both fish medicine and the aquaculture industry. The results of standard hematology and clinical chemistry analysis were evaluated in juvenile rainbow trout at 4, 6, 9, 15 and 19 months of age. Values for PCV and RBC indices were significantly lower, and plasma protein concentration was significantly higher in younger fish. Total WBC and lymphocyte counts were significantly higher in fish at 6 and 9 months of age, while neutrophil and monocyte counts were higher at 6, 9 and 15 months. Eosinophil counts were significantly higher in 9 month old fish. The majority of hematologic values fell within previously established reference intervals, indicating that only slight modification to the intervals is necessary for evaluating hematologic results of rainbow trout at different ages. The following analytes deviated sufficiently from adult reference intervals to warrant separate reference values: plasma protein concentration at 4 months, WBC and lymphocyte counts at 15 and 19 months, and thrombocyte-like-cells at 9 months of age. Values for most biochemical analytes were significantly different among age groups except for creatinine and potassium concentrations. Comparisons with reference intervals were not made for biochemical analytes, because established reference intervals were not available.

  14. Streptococcus agalactiae isolates of serotypes Ia, III and V from human and cow are able to infect tilapia.

    Science.gov (United States)

    Chen, Ming; Wang, Rui; Luo, Fu-Guang; Huang, Yan; Liang, Wan-Wen; Huang, Ting; Lei, Ai-Ying; Gan, Xi; Li, Li-Ping

    2015-10-22

    Recent studies have shown that group B streptococcus (GBS) may be infectious across hosts. The purpose of this study is to investigate the pathogenicity of clinical GBS isolates with serotypes Ia, III and V from human and cow to tilapia and the evolutionary relationship among these GBS strains of different sources. A total of 27 clinical GBS isolates from human (n=10), cow (n=2) and tilapia (n=15) were analyzed using serotyping, multi-locus sequence typing (MLST) and pulsed-field gel electrophoresis (PFGE). Among them, 15 isolates were tested for their pathogenicity to tilapia. The results showed that five human GBS strains (2 serotype III, 2 serotype Ia and 1 serotype V) infected tilapia with mortality rate ranging from 56.67% to 100%, while the other five human GBS strains tested were unable to infect tilapia. In addition, two cow GBS strains C001 and C003 of serotype III infected tilapia. However, they had significantly lower pathogenicity than the five human strains. Furthermore, human GBS strains H005 and H008, which had very strong ability to infect tilapia, had the same PFGE pattern. MLST analysis showed that the five human and the two cow GBS strains that were able to infect tilapia belonged to clonal complexes CC19, CC23 and CC103. The study for the first time confirmed that human or cow GBS clonal complexes CC19, CC23 and CC103 containing strains with serotypes Ia, III and V could infect tilapia and induce clinical signs under experimental conditions. PMID:26255553

  15. The impacts of non-tariff barriers on the export price of Vietnamese catfish

    OpenAIRE

    Khuu, Thi Phuong Dong

    2012-01-01

    The aims of this study to identify the impacts of non-tariff barriers (NTBs) on Vietnamese catfish export price in the international market. The time-series monthly data from 1999 to 2011 was used in our paper. Base on the demand and supply equilibrium theory, we constructed the function of Vietnamese catfish export price. The unit toot test results showed that our data was stationary at differenced level. Therefore, the econometric models, such as first-differenced model, Error correction mo...

  16. Comparative analysis of catfish BAC end sequences with the zebrafish genome

    OpenAIRE

    Abernathy Jason; Xu Peng; Somridhivej Benjaporn; Ninwichian Parichart; Wang Shaolin; Jiang Yanliang; Liu Hong; Kucuktas Huseyin; Liu Zhanjiang

    2009-01-01

    Abstract Background Comparative mapping is a powerful tool to transfer genomic information from sequenced genomes to closely related species for which whole genome sequence data are not yet available. However, such an approach is still very limited in catfish, the most important aquaculture species in the United States. This project was initiated to generate additional BAC end sequences and demonstrate their applications in comparative mapping in catfish. Results We reported the generation of...

  17. College Students' Opinions of U.S. Farm-Raised Catfish

    OpenAIRE

    Hanson, Terrill R.; Rose, Patrick

    2011-01-01

    A survey focusing on factors related to consumption of fish and seafood, including catfish, and targeted at college-aged students was developed and administered in conjunction with Auburn University's Earth Day dining promotion. Six hundred forty completed surveys were obtained over two days in April, 2012. Findings suggest that students had an overall positive opinion toward catfish, citing enjoyment of flavor (44 percent), better texture (38 percent), less expensive (43 percent), and greate...

  18. Whole genome comparative analysis of channel catfish (Ictalurus punctatus) with four model fish species

    OpenAIRE

    Jiang, Yanliang; Gao, Xiaoyu; Liu, Shikai; Zhang, Yu; Liu, Hong; Sun, Fanyue; Bao, Lisui; Waldbieser, Geoff; Liu, Zhanjiang

    2013-01-01

    Background Comparative mapping is a powerful tool to study evolution of genomes. It allows transfer of genome information from the well-studied model species to non-model species. Catfish is an economically important aquaculture species in United States. A large amount of genome resources have been developed from catfish including genetic linkage maps, physical maps, BAC end sequences (BES), integrated linkage and physical maps using BES-derived markers, physical map contig-specific sequences...

  19. Comparative analysis of catfish BAC end sequences with the zebrafish genome

    OpenAIRE

    Liu, Hong; Jiang, Yanliang; Wang, Shaolin; Ninwichian, Parichart; Somridhivej, Benjaporn; Xu, Peng(Academy of Mathematics and Systems Science, Chinese Academy of Sciences, 100190, Beijing, China); Abernathy, Jason; Kucuktas, Huseyin; Liu, Zhanjiang

    2009-01-01

    Background Comparative mapping is a powerful tool to transfer genomic information from sequenced genomes to closely related species for which whole genome sequence data are not yet available. However, such an approach is still very limited in catfish, the most important aquaculture species in the United States. This project was initiated to generate additional BAC end sequences and demonstrate their applications in comparative mapping in catfish. Results We reported the generation of 43,000 B...

  20. Delivering the Goods: Lessons Learned from Direct Delivery of Kentucky Catfish

    OpenAIRE

    Berney, Gerald; Tropp, Debra; Clifton, Kimberly; McKenna, Larissa

    2007-01-01

    USDA initiated a pilot study in cooperation with KDA and PAAC that examined the marketing, transportation, and delivery strategies of the catfish processing cooperative. The information gathered should prove useful to many groups involved in this type of enterprise. The study had several emphases: • Describing the marketing channels, customers, and products used by the cooperative in selling catfish. • Describing the procedures and equipment used in PAAC’s direct delivery operation. • Examini...

  1. INCREASING FISHERY ADDED VALUE THROUGH DEVELOPMENT OF "OTAK-OTAK" MADE FROM CATFISH

    OpenAIRE

    Saadah

    2014-01-01

    INCREASING FISHERY ADDED VALUE THROUGH DEVELOPMENT OF "OTAK-OTAK" MADE FROM CATFISH Saadah,1 Abu Bakar Tawali.1 Meta Mahendradatta1 Budimawan,2 (1Faculty of Agriculture, Hasanuddin University, 2 Faculty of Marine Sciences and Fisheries, Hasanuddin University) Abstract This research aimed to 1. Introduce Surimi technology in manufacturing process of otak-otak , 2. Compile Standard Operating Procedure of Surimi processing made from catfish, 3. Compile Standard Operating Procedure of otak-otak p...

  2. Relative condition factor and food and feeding habits of two ariid catfish from Mumbai waters

    OpenAIRE

    Deo, A.D.; Venkateshvaran, K.; Devaraj, M.

    2010-01-01

    Condition factor based on length-weight relationship and food and feeding habits of Arius dussumieri (Black lip sea catfish) and Osteogeneiosus militaris (Soldier catfish) from the Mumbai coast have been studied. Relative Condition Factor showed variations on a monthly basis, and appear to be influenced by feeding and breeding activities. Both the species studied are carnivorous bottom feeders, with crustaceans followed by other smaller fishes forming the major food item in the gut contents.

  3. On-farm feed resources for catfish (Clarias gariepinus) production in Laos

    OpenAIRE

    Phonekhampheng, Oudom

    2008-01-01

    The aim of the thesis was to collected information African catfish (Clarias gariepinus) production systems, and the chemical composition and nutritive value of potentially available feedstuffs. Moreover, the apparent digestibility (AD) of nutrient and amino acids (AA) in raw, sun-dried and ensiled Golden Apple snails (GAS) was evaluated, as well as the potential of GAS to replace fish meal in the diet for growing African catfish fingerlings. The farmers used traditional feedstuffs such as mai...

  4. Karyotype Analysis of the New Catfish Mystus ngasep (Siluriformes: Bagridae) from Manipur, India

    OpenAIRE

    Singh, Sukham Sanjabihari; Singh, Chingakham Brajakishor; WAIKHOM, Gusheinzed

    2013-01-01

    Karyotypic and cytogenetic characteristics of catfish Mystus ngasep, a new species of bagrid catfish described from the Northeast India, Manipur was studied for the first time by examining 200 metaphase spreads chromosome from the kidney cells of 25 healthy specimens. The diploid chromosome number of this species was 2n=56 and the total fundamental arm number was determined as NF=90. The karyotype consisted of 12 Metacentric (m), 22 Submetacentric (Sm), 8 Subtelocentric (St) and 14 Teloce...

  5. Distribution of catfishes in wetlands of two flood plain districts in Tamil Nadu, India

    OpenAIRE

    B. Rajagopal; Davidar, P.

    2013-01-01

    A study was conducted on the distribution of catfishes in selected wetlands in Kancheepuram and Kanyakumari districts of Tamil Nadu, southern India. Different types of wetlands such as tanks, pools, lakes, open wells and estuaries were selected for the study based on their different environmental set up. Fishes were collected with the help of fishermen using cast and seine nets. Twelve species of catfishes from five families (Ariidae, Bagridae, Heteropneustidae, Schilbeidae and Siluridae) wer...

  6. Feeding Nile tilapia with artificial diets and dried bioflocs biomass

    Directory of Open Access Journals (Sweden)

    Nayara Nunes Caldini

    2015-10-01

    Full Text Available The effects of supplying dried bioflocs biomass to Nile tilapia juveniles were investigated in the present work. Fish were stocked in experimental rearing tanks for eight weeks. Selected variables of water quality, growth performance and effluent quality were evaluated. Fish were given different combinations of artificial diets and biofloc biomass, in wet (in natura or dry form. As the supply of artificial diet decreased, the allowance of biofloc biomass increased in the same proportion. Biofloc biomass was produced in two 500-L tanks that received daily applications of dry molasses to adjust the C: N ratio of the water to 15: 1. The concentration of nitrite in water was only reduced in the tanks receiving wet bioflocs. The fish growth performance was poorer in the tanks that received dried biofloc biomass than in the tanks with wet biofloc biomass. Given the lack of positive results, there is no justification to dry the biofloc biomass aiming at delivering it as a dry biomass to reared fish.

  7. Nile tilapia culture on domestic effluent treated in stabilization ponds.

    Directory of Open Access Journals (Sweden)

    Clovis Matheus Pereira

    2009-03-01

    Full Text Available The performance and filet quality of tilapias (Oreochromis niloticus culture in effluent stabilization lagoons was tested at the densities of 3 fish/m2 (T3, 7 fish/m2 (T2 and 7 fish/m2 in clean water + diet (T1 with 3 repetitions in tanks of 2.57m2 and 0.60m of water column with supplemental aeration. Fish culture in clean water plus diet (T1 presented the highest growth. The higher density T3 (7/m2 compared to T2 (3/m2 did not result in any difference of total production (p > 0.05 but this was compensated by the increased individual fish growth rate at lower density. The conditions that sustain fish survival culture with ETE effluent were attested by the high survival (> 90% under both treatments, but only 10% of the water samples from T2 and T3 N-total ammonium was favorable for fish growth (< 2.0mg/L. The rearing system improved the effluent quality, reducing the total organic nitrogen and the solids in suspension. The faecal coliforms, Salmonella sp. and Staphylococcus aureus from the effluent and fish were verified to be within the standards laid down by the World Health Organization (WHO.

  8. The colonization dynamics of the gut microbiota in tilapia larvae.

    Directory of Open Access Journals (Sweden)

    Christos Giatsis

    Full Text Available The gut microbiota of fish larvae evolves fast towards a complex community. Both host and environment affect the development of the gut microbiota; however, the relative importance of both is poorly understood. Determining specific changes in gut microbial populations in response to a change in an environmental factor is very complicated. Interactions between factors are difficult to separate and any response could be masked due to high inter-individual variation even for individuals that share a common environment. In this study we characterized and quantified the spatio-temporal variation in the gut microbiota of tilapia larvae, reared in recirculating aquaculture systems (RAS or active suspension tanks (AS. Our results showed that variation in gut microbiota between replicate tanks was not significantly higher than within tank variation, suggesting that there is no tank effect on water and gut microbiota. However, when individuals were reared in replicate RAS, gut microbiota differed significantly. The highest variation was observed between individuals reared in different types of system (RAS vs. AS. Our data suggest that under experimental conditions in which the roles of deterministic and stochastic factors have not been precisely determined, compositional replication of the microbial communities of an ecosystem is not predictable.

  9. The colonization dynamics of the gut microbiota in tilapia larvae.

    Science.gov (United States)

    Giatsis, Christos; Sipkema, Detmer; Smidt, Hauke; Verreth, Johan; Verdegem, Marc

    2014-01-01

    The gut microbiota of fish larvae evolves fast towards a complex community. Both host and environment affect the development of the gut microbiota; however, the relative importance of both is poorly understood. Determining specific changes in gut microbial populations in response to a change in an environmental factor is very complicated. Interactions between factors are difficult to separate and any response could be masked due to high inter-individual variation even for individuals that share a common environment. In this study we characterized and quantified the spatio-temporal variation in the gut microbiota of tilapia larvae, reared in recirculating aquaculture systems (RAS) or active suspension tanks (AS). Our results showed that variation in gut microbiota between replicate tanks was not significantly higher than within tank variation, suggesting that there is no tank effect on water and gut microbiota. However, when individuals were reared in replicate RAS, gut microbiota differed significantly. The highest variation was observed between individuals reared in different types of system (RAS vs. AS). Our data suggest that under experimental conditions in which the roles of deterministic and stochastic factors have not been precisely determined, compositional replication of the microbial communities of an ecosystem is not predictable. PMID:25072852

  10. An obscure disease of rainbow trout

    Science.gov (United States)

    Rucker, R.R.; Yasutake, W.T.; Wedemeyer, G.

    1970-01-01

    An annul mortality among Rainbow Trout (Salmo gairdneri) has plagued the Shelton Hatchery of the Washington State Department of Game for the last several years. No infectious agent could be isolated from the moribund fish, but histopathologica1 changes in the liver of 1-month-old fish suggested the presence of a toxic substance. Scoliosis in 3-month-old fish suggested a possible deficiency in vitamin C. With this background in mind, we designed studies to determine the nature and source of possible toxicants and the role of vitamin C deficiency in the etiology of this disease.

  11. Diel movement of brown trout in a southern Appalachian River

    Science.gov (United States)

    Bunnell, D.B., Jr.; Isely, J.J.; Burrell, K.H.; Van Lear, D. H.

    1998-01-01

    Radio telemetry was used to monitor the diel movement of 22 brown trout Salmo trutta (268-446 mm in total length, TL) in the Chattooga River watershed. Forty-seven diel tracks, locating individuals once per hour for 24 consecutive hours, were collected for four consecutive seasons. High variability in movement both within and among individual brown trout resulted in similar seasonal means in total distance moved, diel range, and displacement. The majority of fish moved a total distance of less than 80 m within a diel range of less than 80 m and had a displacement of less than 10 m. Brown trout were more likely to occur in pool habitat independent of season or period of the day. Hourly movement patterns differed among seasons. During the winter and fall, trout moved only around sunrise; during the spring, they moved around sunrise, sunset, and intermittently throughout the night. Large brown trout (>375 mm, TL) were found to move greater total distances and establish wider diel ranges than small brown trout. Overall, most brown trout exhibited restricted diel movement within a single riffle-pool or run-pool sequence.

  12. Reevaluation of lake trout and lake whitefish bioenergetics models

    Science.gov (United States)

    Madenjian, Charles P.; Pothoven, Steve A.; Kao, Yu-Chun

    2013-01-01

    Using a corrected algorithm for balancing the energy budget, we reevaluated the Wisconsin bioenergetics model for lake trout (Salvelinus namaycush) in the laboratory and for lake whitefish (Coregonus clupeaformis) in the laboratory and in the field. For lake trout, results showed that the bioenergetics model slightly overestimated food consumption by the lake trout when they were fed low and intermediate rations, whereas the model predicted food consumption by lake trout fed ad libitum without any detectable bias. The slight bias in model predictions for lake trout on restricted rations may have been an artifact of the feeding schedule for these fish, and we would therefore recommend application of the Wisconsin lake trout bioenergetics model to lake trout populations in the field without any revisions to the model. Use of the Wisconsin bioenergetics model for coregonids resulted in overestimation of food consumption by lake whitefish both in the laboratory and in the field by between 20 and 30%, on average. This overestimation of food consumption was most likely due to overestimation of respiration rate. We therefore adjusted the respiration component of the bioenergetics model to obtain a good fit to the observed consumption in our laboratory tanks. The adjusted model predicted the consumption in the laboratory and the field without any detectable bias. Until a detailed lake whitefish respiration study can be conducted, we recommend application of our adjusted version of the Wisconsin generalized coregonid bioenergetics model to lake whitefish populations in the field.

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

    OpenAIRE

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

    2015-01-01

    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. ...

  14. Introduced brown trout alter native acanthocephalan infections in native fish.

    Science.gov (United States)

    Paterson, Rachel A; Townsend, Colin R; Poulin, Robert; Tompkins, Daniel M

    2011-09-01

    1. Native parasite acquisition provides introduced species with the potential to modify native host-parasite dynamics by acting as parasite reservoirs (with the 'spillback' of infection increasing the parasite burdens of native hosts) or sinks (with the 'dilution' of infection decreasing the parasite burdens of native hosts) of infection. 2. In New Zealand, negative correlations between the presence of introduced brown trout (Salmo trutta) and native parasite burdens of the native roundhead galaxias (Galaxias anomalus) have been observed, suggesting that parasite dilution is occurring. 3. We used a multiple-scale approach combining field observations, experimental infections and dynamic population modelling to investigate whether native Acanthocephalus galaxii acquisition by brown trout alters host-parasite dynamics in native roundhead galaxias. 4. Field observations demonstrated higher infection intensity in introduced trout than in native galaxias, but only small, immature A. galaxii were present in trout. Experimental infections also demonstrated that A. galaxii does not mature in trout, although parasite establishment and initial growth were similar in the two hosts. Taken together, these results support the hypothesis that trout may serve as an infection sink for the native parasite. 5. However, dynamic population modelling predicts that A. galaxii infections in native galaxias should at most only be slightly reduced by dilution in the presence of trout. Rather, model exploration indicates parasite densities in galaxias are highly sensitive to galaxias predation on infected amphipods, and to relative abundances of galaxias and trout. Hence, trout presence may instead reduce parasite burdens in galaxias by either reducing galaxias density or by altering galaxias foraging behaviour. PMID:21426342

  15. Seasonal movement of brown trout in a southern appalachian river

    Science.gov (United States)

    Burrell, K.H.; Isely, J.J.; Bunnell, D.B., Jr.; Van Lear, D. H.; Dolloff, C.A.

    2000-01-01

    Radio telemetry was used to evaluate the seasonal movement, activity level, and home range size of adult brown trout Salmo trutta in the Chattooga River watershed, one of the southernmost coldwater stream systems in the United States. In all, 27 adult brown trout (262-452 mm total length) were successfully monitored from 16 November 1995 to 15 December 1996. During the day, adult brown trout were consistently found in small, well-established home ranges of less than 270 m in stream length. However, 8 of a possible 18 study fish made spawning migrations during a 2-week period in November 1996. The daytime locations of individual fish were restricted to a single pool or riffle-pool combination, and fish were routinely found in the same location over multiple sampling periods. Maximum upstream movement during spawning was 7.65 km, indicating that brown trout in the Chattooga River have the ability to move long distances. Spawning brown trout returned to their prespawning locations within a few days after spawning. Brown trout maintained larger home ranges in winter than in other seasons. When spawning-related movement was deleted from the analysis, brown trout moved more on a weekly basis in fall than in summer. Brown trout were more active in fall and winter than in spring and summer. Apart from spawning migrations, displacement from established home ranges was not observed for any fish in the study. Although summer water temperatures reached and exceeded reported upper thermal-preference levels, brown trout did not move to thermal refuge areas in nearby tributaries during the stressful summer periods.

  16. The channel catfish genome sequence provides insights into the evolution of scale formation in teleosts.

    Science.gov (United States)

    Liu, Zhanjiang; Liu, Shikai; Yao, Jun; Bao, Lisui; Zhang, Jiaren; Li, Yun; Jiang, Chen; Sun, Luyang; Wang, Ruijia; Zhang, Yu; Zhou, Tao; Zeng, Qifan; Fu, Qiang; Gao, Sen; Li, Ning; Koren, Sergey; Jiang, Yanliang; Zimin, Aleksey; Xu, Peng; Phillippy, Adam M; Geng, Xin; Song, Lin; Sun, Fanyue; Li, Chao; Wang, Xiaozhu; Chen, Ailu; Jin, Yulin; Yuan, Zihao; Yang, Yujia; Tan, Suxu; Peatman, Eric; Lu, Jianguo; Qin, Zhenkui; Dunham, Rex; Li, Zhaoxia; Sonstegard, Tad; Feng, Jianbin; Danzmann, Roy G; Schroeder, Steven; Scheffler, Brian; Duke, Mary V; Ballard, Linda; Kucuktas, Huseyin; Kaltenboeck, Ludmilla; Liu, Haixia; Armbruster, Jonathan; Xie, Yangjie; Kirby, Mona L; Tian, Yi; Flanagan, Mary Elizabeth; Mu, Weijie; Waldbieser, Geoffrey C

    2016-01-01

    Catfish represent 12% of teleost or 6.3% of all vertebrate species, and are of enormous economic value. Here we report a high-quality reference genome sequence of channel catfish (Ictalurus punctatus), the major aquaculture species in the US. The reference genome sequence was validated by genetic mapping of 54,000 SNPs, and annotated with 26,661 predicted protein-coding genes. Through comparative analysis of genomes and transcriptomes of scaled and scaleless fish and scale regeneration experiments, we address the genomic basis for the most striking physical characteristic of catfish, the evolutionary loss of scales and provide evidence that lack of secretory calcium-binding phosphoproteins accounts for the evolutionary loss of scales in catfish. The channel catfish reference genome sequence, along with two additional genome sequences and transcriptomes of scaled catfishes, provide crucial resources for evolutionary and biological studies. This work also demonstrates the power of comparative subtraction of candidate genes for traits of structural significance. PMID:27249958

  17. Sensitivity of Trout to Chronic Acute Exposure to Selenium

    DEFF Research Database (Denmark)

    Nielsen, Gunnar Gissel; Nielsen, M. Gissel

    1978-01-01

    Trout were exposed to selenite (Na2SeO3) solutions of varying concentrations (0.1-100 ppm Se) for periods of up to 4 wk. A chronic exposure to 0.1 ppm Se or less is non-lethal to trout. Lethality at higher concentrations depends on the length of exposure. Trout that survive for 10 days in tap......-water after contamination will not die as a result of Se toxicity and can safely be used for human consumption....

  18. 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...... 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...

  19. ERM booster vaccination of Rainbow trout using diluted bacterin

    DEFF Research Database (Denmark)

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

    2016-01-01

    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...

  20. Acoustic estimates of abundance and distribution of spawning lake trout on Sheboygan Reef in Lake Michigan

    Science.gov (United States)

    Warner, D.M.; Claramunt, R.M.; Janssen, J.; Jude, D.J.; Wattrus, N.

    2009-01-01

    Efforts to restore self-sustaining lake trout (Salvelinus namaycush) populations in the Laurentian Great Lakes have had widespread success in Lake Superior; but in other Great Lakes, populations of lake trout are maintained by stocking. Recruitment bottlenecks may be present at a number of stages of the reproduction process. To study eggs and fry, it is necessary to identify spawning locations, which is difficult in deep water. Acoustic sampling can be used to rapidly locate aggregations of fish (like spawning lake trout), describe their distribution, and estimate their abundance. To assess these capabilities for application to lake trout, we conducted an acoustic survey covering 22 km2 at Sheboygan Reef, a deep reef (trout, that lake trout were 1–2 m above bottom, and that spawning took place over specific habitat. Lake trout density exhibited a high degree of spatial structure (autocorrelation) up to a range of ~190 m, and highest lake trout and egg densities occurred over rough substrates (rubble and cobble) at the shallowest depths sampled (36–42 m). Mean lake trout density in the area surveyed (~2190 ha) was 5.8 fish/ha and the area surveyed contained an estimated 9500–16,000 large lake trout. Spatial aggregation in lake trout densities, similarity of depths and substrates at which high lake trout and egg densities occurred, and relatively low uncertainty in the lake trout density estimate indicate that acoustic sampling can be a useful complement to other sampling tools used in lake trout restoration research.

  1. Spawning Behaviour and the Softmouth Trout Dilemma

    Directory of Open Access Journals (Sweden)

    Esteve Manu

    2014-07-01

    Full Text Available Morphological, ecological and molecular data sets do not completely agree on the phylogenetic placement of the softmouth trout, Salmo (Salmothymus obtusirostris (Heckel. Molecules posit that softmouths are closely related to brown trout, Salmo trutta L. while some morphological, ecological and life history traits place them in the most basal position of the Salmoninae subfamily between grayling (Thymallus and lenok (Brachymystax. Here we add an additional source of data, behavioural characters based on the first reported observations of softmouth spawning. During spawning softmouth females present three important behaviours not found in the other Salmo members: they continually abandon their nests, rarely staying on them for periods over nine minutes; they expel different batches of eggs at the same nest at intervals of several minutes; and they do not cover their eggs immediately after spawning. These three behaviours are intriguing for two reasons: 1 they are possible homologous to behaviours found in grayling females; 2 when coupled to the nest digging behaviour-widespread in all the salmonines, including softmouths, they seem to be mal-adaptive.

  2. Electrotransfer of the tilapia piscidin 3 and tilapia piscidin 4 genes into skeletal muscle enhances the antibacterial and immunomodulatory functions of Oreochromis niloticus.

    Science.gov (United States)

    Lin, Wen-Chun; Chang, Hsiao-Yun; Chen, Jyh-Yih

    2016-03-01

    Tilapia piscidin 3 (TP3) and tilapia piscidin 4 (TP4) are antimicrobial peptides recently isolated from Oreochromis niloticus. We previously showed that synthetic TP3 and TP4 possessed antimicrobial activities. Here, we analyzed the bactericidal abilities and immunomodulatory properties of these AMPs following the electroporation of pCMV-GFP-TP3 or pCMV-GFP-TP4 plasmid into tilapia (O. niloticus) muscle and subsequent infection with Vibrio vulnificus or Streptococcus agalactiae. Prior overexpression of TP3 or TP4 in tilapia muscle tissues efficiently reduced bacterial numbers at 24 and 48 h after V. vulnificus infection and reduced bacterial numbers at 24 h after S. agalactiae infection compared to numbers in controls expressing pCMV-GFP (EGFP). Electroporation of pCMV-EGFP-TP3 (TP3) or pCMV-EGFP-TP4 (TP4) significantly increased expression of several immune-related genes in muscle (IL-1β (12 h, TP3), IL-8 (12 h, TP3), TGFβ (3 h, TP4), and IκB (48 h, TP3, TP4)) and decreased the expression of TLR5 (12 h and 24 h, TP3) after V. vulnificus infection. Following S. agalactiae infection, expression of the following genes was significantly decreased in muscle: IL-1β (12 h, TP3), IL-8 (12 h, TP3, TP4), TLR5 (3 h-24 h, TP3, TP4), TGFβ (3 h, TP4; 24 h, TP3, TP4), and IκB (3 h, TP3). These data suggest that TP3 and TP4 exert antimicrobial effects after overexpression in the O. niloticus muscle, and also play important roles in the regulation of immune-related gene expression. PMID:26828260

  3. Assessing the effects of pulsed waterborne copper toxicity on life-stage tilapia populations.

    Science.gov (United States)

    Chen, Wei-Yu; Lin, Chia-Jung; Ju, Yun-Ru; Tsai, Jeng-Wei; Liao, Chung-Min

    2012-02-15

    The impact of environmentally pulsed metal exposure on aquatic organisms is poorly understood experimentally. The purpose of this study was to provide an analysis methodology for assessing the effects of pulsed waterborne copper (Cu) on life-stage tilapia populations. We conducted 10-day exposure experiments to obtain toxicokinetic parameters for larva, juvenile, and adult tilapia exposed to pulsed Cu. We linked threshold damage model and biotic ligand model to assess the survival probability for tilapia populations to pulsed Cu exposure. Here we showed that the change in exposure patterns did change substantially survival rates for each life stage of tilapia. We indicated that an apparent difference in time course of survival probability between pulsed and constant Cu exposures was found in each life stage. We concluded that the life-stage factor needs to be incorporated into studies of species interactions under different disturbance regimes. This study suggested that life-stage-specific toxicokinetic parameters and adequate water chemistry might be important to consider in risk assessment of population survivorship for aquatic species under pulsed exposure scenarios. PMID:22264916

  4. PROLONGED FASTING AND CORTISOL REDUCE MYOSTATIN MRNA LEVELS IN TILAPIA LARVAE, SHORT-TERM FASTING ELEVATES

    Science.gov (United States)

    Myostatin negatively regulates muscle growth and development and has recently been characterized in several fishes. We measured fasting myostatin mRNA levels in adult tilapia skeletal muscle and in whole larvae. Although fasting reduced some growth indices in adults, skeletal muscle myostatin mRNA...

  5. Application of Highly Purified Electrolyzed Chlorine Dioxide for Tilapia Fillet Disinfection

    Directory of Open Access Journals (Sweden)

    Chen-Hsing Yu

    2014-01-01

    Full Text Available This research aimed to develop an electrolysis method to generate high-concentration chlorine dioxide (ClO2 for tilapia fillet disinfection. The designed generator produced up to 3500 ppm of ClO2 at up to 99% purity. Tilapia fillets were soaked in a 400 ppm ClO2 solution for 5, 10, and 25 min. Results show that total plate counts of tilapia, respectively, decreased by 5.72 to 3.23, 2.10, and 1.09 log CFU/g. In addition, a 200 ppm ClO2 solution eliminated coliform bacteria and Escherichia coli in 5 min with shaking treatment. Furthermore, ClO2 and trihalomethanes (THMs residuals on tilapia fillets were analyzed by GC/MS and were nondetectable (GC-MS detection limit was 0.12 ppb. The results conform to Taiwan’s environmental protection regulations and act governing food sanitation.

  6. Suitability of Using Duckweed as Feed and Treated Sewage as Water Source in Tilapia Aquaculture

    International Nuclear Information System (INIS)

    Use of treated effluent and duckweed biomass from a pilot-scale UASB-duckweed ponds system treating domestic sewage was evaluated in rearing Nile tilapia (Oreochromis niloticus). Nutritional value of duckweed as sole feed was compared with wheat bran. Two sources of water were used for each feed trial, treated-sewage and freshwater. The experiment was conducted in parallel with a conventional settled sewage-fed fishpond. Results of growth performance demonstrated that, in case of freshwater ponds specific growth rate (SGR) of tilapia fed on fresh duckweed was significantly (p 0.05) was observed between the two feeding regimes in treated sewage fed ponds. The SGR of tilapia reared in the treated sewage-wheat bran-fed pond (TWP) was significant higher (p <0.01) than the SGR in the freshwater-wheat bran-fed pond (FWP). On the other hand, due to the early spawning in the treated sewage-duckweed fed pond (TOP) SGR of tilapia in the latter was significantly lower (p <0.05) than the SGR in the freshwater-duckweed-fed pond (FDP). The results of net fish yield were 11.8, 8.9, 9.6 and 6.4 ton/ha/y in TDP, TWP, FDP and FWP, respectively. negative net yield (-0.16 ton/ha/y) was observed in the settled sewage- fed pond (SSP) due to high mortality

  7. The Fish Immune System, with Particular Emphasis on Nile Tilapia (Oreochromis niloticus)

    Science.gov (United States)

    Knowledge of the immune system is important for a better understanding of disease resistance mechanisms and the development of vaccine strategies. This understanding is also relevant in the control of infectious diseases under intensive tilapia farming. The immune system first recognizes the patho...

  8. Effect of transglutaminase on quality characteristics of a value-added product tilapia wastes.

    Science.gov (United States)

    Monteiro, Maria Lúcia Guerra; Mársico, Eliane Teixeira; Lázaro, César Aquiles; da Silva Canto, Anna Carolina Vilhena Cruz; Lima, Bruno Reis Carneiro da Costa; da Cruz, Adriano Gomes; Conte-Júnior, Carlos Adam

    2015-05-01

    The aim of this work was to evaluate the physico-chemical, instrumental color and texture, and sensory qualities of restructured tilapia steaks elaborated with small sized (non-commercial) tilapia fillets and different levels of microbial transglutaminase (MTG). Four concentrations of MTG were used: CON (0 % MTG), T1 (0.1 % MTG), T2 (0.5 % MTG), and T3 (0.8 % MTG). In addition, bacterial content and pH shifts were also evaluated during 90 days of frozen storage. The different levels of MTG did not affect (P > 0.05) either the proximate composition of the restructured tilapia steaks or the bacterial growth during the frozen storage. MTG improved (P salty taste, succulence and tenderness) attributes; strongly contributing to greater overall acceptance. Therefore, restructured tilapia steaks manufactured with MTG are potentially valued-added products with good consumer acceptance and better purchase-intention than steaks formulated with 0 % MTG. PMID:25892758

  9. Physicochemical and sensory characteristics of snack made with minced Nile tilapia

    Directory of Open Access Journals (Sweden)

    João De Paula Cortez Netto

    2014-09-01

    Full Text Available Nile tilapia is one of the major fish species cultivated worldwide and in Brazil. The tilapia fillet yield is between 30-35%, thus around 70% of waste is generated. A portion of this waste can be used to obtain minced fish, and the resulting product can be used as meat raw material to prepare fish snacks. The aim of this study was to produce fish snacks containing different inclusion levels (20, 30, and 40% of minced fish obtained from Nile tilapia processing waste and evaluate their physicochemical characteristics and sensory acceptance. Protein content, ash, water activity, and hardness increased with increasing inclusion of minced fish. The scores obtained in the sensory evaluation were: flavor acceptance (from 7.2 to 5.7, texture (from 7.4 to 5.3, overall acceptance (from 7.1 to 5.9, and willingness to purchase (from 4.0 to 3.1. This study demonstrates that the inclusion of 20 to 40% of minced fish of Nile tilapia in snacks is well accepted and improves their nutritional value without affecting the physicochemical properties.

  10. Apparent digestibility coefficient of duckweed (Lemna minor), fresh and dry for Nile tilapia (Oreochromis niloticus L.)

    NARCIS (Netherlands)

    El-Shafai, S.A.A.M.; El-Gohary, F.; Verreth, J.A.J.; Schrama, J.W.; Gijzen, H.J.

    2004-01-01

    Dry matter (DMD), protein (PD), ash (AD), fat (FD), gross energy (ED) and phosphorus (PhD) digestibility coefficients were determined for five different iso-N fish diets fed to Nile tilapia (Oreochromis niloticus). The control diet contained fishmeal (35%), corn (29%), wheat (20%), wheat bran (10%),

  11. Histopathological alterations in the liver of freshwater teleost Tilapia mossambica in response to cadmium toxicity

    Energy Technology Data Exchange (ETDEWEB)

    Usha Rani, A.; Ramamurthi, R.

    1989-04-01

    The effects of lethal (50 ppm) and sublethal (5 ppm) concentrations of CdCl/sub 2/ on the liver of the freshwater teleost Tilapia mossambica were studied by routine histological techniques. Engorged blood vessels, congestion, vacuolar degeneration of hepatocytes, necrosis of pancreatic cells, and fatty changes in the peripancreatic hepatocytes were the pathological alterations observed in liver.

  12. Antioxidant and antihypertensive activity of gelatin hydrolysate from Nile tilapia skin

    OpenAIRE

    Choonpicharn, Sadabpong; Jaturasitha, Sanchai; Rakariyatham, Nuansri; Suree, Nuttee; Niamsup, Hataichanoke

    2014-01-01

    Fish skin, a by-product from fish processing industries, still contains a significant amount of protein-rich material. Gelatin was extracted from Nile tilapia skin with the yield 20.77 ± 0.80 % wet weight. Gelatin was then separately hydrolyzed by proteases, including bromelain, papain, trypsin, flavourzyme, alcalase and neutrase. Low molecular weight gelatin hydrolysate (

  13. Use, fate and ecological risks of antibiotics applied in tilapia cage farming in Thailand

    NARCIS (Netherlands)

    Rico, A.; Oliveira, R.; McDonough, S.; Matser, A.; Khatikarn, J.; Satapornvanit, K.; Nogueira, A.J.A.; Soares, A.M.V.M.; Domingues, I.; Brink, van den P.J.

    2014-01-01

    The use, environmental fate and ecological risks of antibiotics applied in tilapia cage farming were investigated in the Tha Chin and Mun rivers in Thailand. Information on antibiotic use was collected through interviewing 29 farmers, and the concentrations of the most commonly used antibiotics, oxy

  14. beta-adrenoceptors mediate inhibition of lipolysis in adipocytes of tilapia (Oreochromis mossambicus)

    NARCIS (Netherlands)

    Vianen, GJ; Obels, PP; Van Den Thillart, GEEJM; Zaagsma, J

    2002-01-01

    The regulation of triglyceride mobilization by catecholamines was investigated in the teleost fish Oreochromis mossambicus (tilapia) in vivo and in vitro. In vitro experiments were carried out with adipocytes that were isolated for the first time from fish adipose tissue. For the in vivo experiments

  15. Genetic parameters for reproductive traits in female Nile tilapia (Oreochromis niloticus): II. Fecundity and fertility

    NARCIS (Netherlands)

    Trong, T.Q.; Arendonk, van J.A.M.; Komen, J.

    2013-01-01

    Harvest weight is the main trait in Nile tilapia (Oreochromis niloticus) breeding programmes. The effects of selection for harvest weight on female reproductive traits are unknown. In this paper we estimate genetic parameters for reproductive traits and their correlation with harvest weight using fe

  16. HYPOXIA INDUCES HSP 70 PRODUCTION IN JUVENILE NILE TILAPIA, OREOCHROMIS NILOTICUS (L.)

    Science.gov (United States)

    Enzyme linked immunosorbent assay (ELISA) was used to determine levels of the inducible heat shock protein 70 (hsp70) in response to prolonged anoxic conditions in juvenile Nile tilapia. This protein was detected in brain, liver, muscle and head kidney. A significant difference between treatments (...

  17. Salinity Tolerance and Preference of Hatchery Reared Nile Tilapia, Oreochromis niloticus (Linneaus 1758

    Directory of Open Access Journals (Sweden)

    E.O. Lawson

    2011-03-01

    Full Text Available A study was conducted in fisheries laboratory of Department of Fisheries, Lagos State University, Nigeria on salinity tolerance and preference of hatchery reared Nile tilapia, Oreochromis niloticus, (Linneaus, 1758. Tilapias are important candidate species for aquaculture and are increasingly cultured in polyculture system with shrimp. Thus creating a demand for Tilapia genotypes well suited to elevated salinities. O. niloticus is a member of the Family Cichlidae and one of most cultured fish species in Nigeria. It is known for its high prolific rate of breeding and multiplication. Six hundred and sixty (660 fingerlings of the fish measuring between 53-140 mm TL and weighing 8.96 to 21.56 g BW were subjected to salinity regimes of 0-10‰ for 28 days. All the fish survived in 0-7‰, and 100% death was recorded in 9 and 10‰. Different levels of behavioural responses to threat and feeding were observed among the fish. Salinities 0-7‰ were tolerated by the fish, however the most preferred salinity was 1‰. The present study as demonstrated in the laboratory therefore, suggests the possibility of culturing Nile tilapia, O. niloticus in both fresh and low brackish water environments and as added data to the existed reviews on this economically valued fish species. The salinity regimes well that were tolerated and preferred for optimal survival, growth and behavioural performances of O. niloticus are therefore investigated.

  18. Genotype by production environment interaction in the GIFT strain of Nile tilapia (Oreochromis niloticus)

    NARCIS (Netherlands)

    Khaw, H.L.; Ponzonia, R.W.; Hamzah, A.; Abu-Bakara, K.R.; Bijma, P.

    2012-01-01

    Three discrete generations of GIFT fish (Nile tilapia strain, Oreochromis niloticus; a total of 10,065 fish with pedigree and phenotypic information) were tested in pond and cage culture environments to determine genotype by production environment interaction between both environments in Malaysia. L

  19. Productive performance of Nile tilapia (Oreochromis niloticus fed at different frequencies and periods with automatic dispenser

    Directory of Open Access Journals (Sweden)

    R.M.R. Sousa

    2012-02-01

    Full Text Available The performance of Nile tilapia (Oreochromis niloticus raised in cages furnished with an automatic dispenser, supplied at different frequencies (once per hour and once every two hours and periods (daytime, nighttime and both was evaluated. Eighteen 1.0m³ cages were placed into a 2000m² pond, two meters deep with a 5% water exchange. One hundred and seventy tilapias, with initial weight of 16.0±4.9g, were dispersed into each 1m³ cage and the feed ration was adjusted every 21 days with biometry. Data was collected from March to July (autumn and winter. Significant difference to final weight (P<0.05 among treatments was observed. The increase in feeding frequency improves the productive performance of Nile tilapias in cages and permitted better management of the food. The better feed conversion rate for high feeding frequency (24 times day-1 can result in saving up to 360kg of food for each ton of fish produced, increasing the economic sustenance for tilapia culture and suggesting less environmental pollution.

  20. Effectiveness of early intervention with florfenicol on a Streptococcus iniae infection in blue tilapia

    Science.gov (United States)

    An experimental feeding trial was performed to assess the efficacy of florfenicol (FFC) in controlling Streptococcus iniae infection in blue tilapia, Oreochromis aureus. Doses of FFC tested were 0, 5, 10, 15 and 30 mg active ingredient per kilogram of fish body weight (BW) per day. Administration ...

  1. Effect of parasitism on vaccine efficacy against Streptococcus iniae in Nile tilapia

    Science.gov (United States)

    Limited information is available on vaccine performance in parasitized fish. The objective of this study was to determine if parasitism of fish affected vaccine efficacy. Antibody level, hematology and survival of Nile tilapia vaccinated with a modified S. iniae bacterin were compared among non-para...

  2. Optimizing fish meal-free commercial diets for Nile Tilapia, Oreochromis niloticus

    Science.gov (United States)

    A feeding trial was conducted in a closed recirculating aquaculture system with Nile tilapia Oreochromis niloticus juveniles (mean weight, 6.81 g) to examine the response to a practical diet containing protein primarily from menhaden fish meal (FM) and soybean meal (SBM) (control, Diet 1) or to diet...

  3. Complete genome sequence of a virulent Streptococcus agalactiae strain 138P isolated from diseased Nile tilapia

    Science.gov (United States)

    Streptococcus agalactiae strain 138P was isolated from the kidney of diseased Nile tilapia in Idaho during a 2007 streptococcal disease outbreak. The full genome of S. agalactiae 138P is 1,838,716 bp. The availability of this genome will allow comparative genomics to identify genes for antigen disco...

  4. Complete Genome Sequence of a Virulent Streptococcus agalactiae Strain, 138P, Isolated from Diseased Nile Tilapia

    OpenAIRE

    Pridgeon, Julia W.; Zhang, Dunhua

    2014-01-01

    Streptococcus agalactiae strain 138P was isolated from the kidney of diseased Nile tilapia in Idaho during a 2007 streptococcal disease outbreak. The full genome sequence of S. agalactiae 138P is 1,838,701 bp. The availability of this genome will allow comparative genomics analysis to identify genes for antigen discovery and vaccine development.

  5. Draft Genome Sequences of Streptococcus agalactiae Serotype Ia and III Isolates from Tilapia Farms in Thailand

    OpenAIRE

    Areechon, Nontawith; Kannika, Korntip; Hirono, Ikuo; Kondo, Hidehiro; Unajak, Sasimanas

    2016-01-01

    Streptococcus agalactiae serotypes Ia and III were isolated from infected tilapia in cage and pond culture farms in Thailand during 2012 to 2014, in which pathogenicity analysis demonstrated that serotype III showed higher virulence than serotype Ia. Here, we report the draft genome sequencing of piscine S. agalactiae serotypes Ia and III.

  6. Draft Genome Sequences of Streptococcus agalactiae Serotype Ia and III Isolates from Tilapia Farms in Thailand.

    Science.gov (United States)

    Areechon, Nontawith; Kannika, Korntip; Hirono, Ikuo; Kondo, Hidehiro; Unajak, Sasimanas

    2016-01-01

    Streptococcus agalactiaeserotypes Ia and III were isolated from infected tilapia in cage and pond culture farms in Thailand during 2012 to 2014, in which pathogenicity analysis demonstrated that serotype III showed higher virulence than serotype Ia. Here, we report the draft genome sequencing of piscineS. agalactiaeserotypes Ia and III. PMID:27013037

  7. Influence of Tricaine Methanesulfonate on Streptococcus agalactiae vaccination of Nile tilapia (Oreochromis niloticus)

    Science.gov (United States)

    Experiments were conducted to study the influence of tricaine methanesulfonate (MS-222) on blood glucose levels and percent cumulative survival of Nile tilapia (Oreochromis niloticus) challenged with Streptococcus agalactiae 30 days post-vaccination with S. agalactiae vaccine or sham-vaccination wit...

  8. Background adaptation and water acidification affect pigmentation and stress physiology of tilapia, Oreochromis mossambicus

    NARCIS (Netherlands)

    Salm, A.L. van der; Spanings, F.A.T.; Gresnigt, R.; Wendelaar Bonga, S.E.; Flik, G.

    2005-01-01

    The ability to adjust skin darkness to the background is a common phenomenon in fish. The hormone alpha-melanophore-stimulating hormone (alphaMSH) enhances skin darkening. In Mozambique tilapia, Oreochromis mossambicus L., alphaMSH acts as a corticotropic hormone during adaptation to water with a lo

  9. Effect of stocking biomass on solids, phytoplankton communities, common off-flavors, and production parameters in a channel catfish biofloc technology production system

    Science.gov (United States)

    The effect of initial channel catfish (Ictalurus punctatus, Rafinesque, 1818) fingerling biomass (1.4, 1.8, or 2.3 kg m-3) on phytoplankton communities, common off-flavors, and stocker catfish production parameters was evaluated in biofloc technology production tanks. Stocker catfish size (145.5 – 1...

  10. G-protein coupled receptor 18 (GPR18) in channel catfish: Expression analysis and efficacy as immunostimulant against Aeromonas hydrophila infection

    Science.gov (United States)

    The objectives of this study were: 1) to determine the transcriptional profiles of G-protein coupled receptor 18 (GPR18) in channel catfish after infection with A. hydrophila compared to that in healthy catfish; 2) to determine whether over-expression of GPR18 in catfish gill cells will offer protec...

  11. Assembly of 500,000 Inter-Specific Catfish Expressed Sequence Tags and Large Scale Gene-Associated Marker Development for Whole Genome Association Studies

    Science.gov (United States)

    Through the Community Sequencing Program, a catfish EST sequencing project was carried out through a collaboration between the catfish research community and the Department of Energy's Joint Genome Institute. Prior to this project, only a limited EST resource from catfish was available for the purpo...

  12. Absorbed dose rate due to intake of natural radionuclides by Tilapia fish (Tilapia nilotica, Linnaeus, 1758) estimated near uranium anomaly at Santa Quiteria, Ceara, Brazil

    International Nuclear Information System (INIS)

    The uranium mining at Santa Quiteria (Santa Quiteria Unit - USQ) is in its environmental licensing phase. Aiming to estimate the radiological environmental impact of the USQ, a monitoring program is underway. However, radioprotection of biota is not explicitly mentioned in Brazilian norms. In order to preserve the biota of the deleterious effects from radiation and to behave in a pro-active way as expected by licensing organs, the present work aims to use an environmental protection methodology, based on the calculation of absorbed dose rate in biota. Thus, selected biomarker was the fish tilapia (Tilapia nilotica, Linnaeus, 1758) and the radionuclides were: uranium (U-238), thorium (Th-232), radium (Ra-226 and Ra-228) and lead (Pb-210). Since there are no exposition limits for biota, in Brazil, the value proposed by the Department of Energy (DOE) of the United States of 3.5 x 103 μGy/y has been used. The derived absorbed dose rate calculated for tilapia was 2.76 x 100 μGy/y, that is less than 0.1 % of the limit established by DOE. The critical radionuclide was U-238, with 99% of the absorbed dose rate. This value of 0.1% of the limit allows to state that in pre-operational conditions analyzed natural radionuclides do not represent a radiological problem to the biota. (author)

  13. Absorbed dose rate due to intake of natural radionuclides by Tilapia fish (Tilapia nilotica, Linnaeus, 1758) estimated near uranium anomaly at Santa Quiteria, Ceara, Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Pereira, Wagner de [Industrias Nucleares do Brasil S.A. (INB), Pocos de Caldas, MG (Brazil). Coordenacao de Protecao Radiologica. Unidade de Tratamento de Minerios], E-mail: wspereira@inb.gov.br; Kelecom, Alphonse [Universidade Federal Fluminense (UFF), Niteroi, RJ (Brazil). Programa de Pos-graduacao em Ciencia Ambiental; Py Junior, Delcy de Azevedo [Industrias Nucleares do Brasil S.A. (INB), Caetite, BA (Brazil). Coordenacao de Protecao Radiologica. Unidade de Concentrado de Uranio], E-mail: Delcy@inb.gov.br

    2007-07-01

    The uranium mining at Santa Quiteria (Santa Quiteria Unit - USQ) is in its environmental licensing phase. Aiming to estimate the radiological environmental impact of the USQ, a monitoring program is underway. However, radioprotection of biota is not explicitly mentioned in Brazilian norms. In order to preserve the biota of the deleterious effects from radiation and to behave in a pro-active way as expected by licensing organs, the present work aims to use an environmental protection methodology, based on the calculation of absorbed dose rate in biota. Thus, selected biomarker was the fish tilapia (Tilapia nilotica, Linnaeus, 1758) and the radionuclides were: uranium (U-238), thorium (Th-232), radium (Ra-226 and Ra-228) and lead (Pb-210). Since there are no exposition limits for biota, in Brazil, the value proposed by the Department of Energy (DOE) of the United States of 3.5 x 10{sup 3} {mu}Gy/y has been used. The derived absorbed dose rate calculated for tilapia was 2.76 x 10{sup 0} {mu}Gy/y, that is less than 0.1 % of the limit established by DOE. The critical radionuclide was U-238, with 99% of the absorbed dose rate. This value of 0.1% of the limit allows to state that in pre-operational conditions analyzed natural radionuclides do not represent a radiological problem to the biota. (author)

  14. Bull Trout Life History, Genetics, Habitat Needs, and Limiting Factors in Central and Northeast Oregon. Annual Report 1996.

    Energy Technology Data Exchange (ETDEWEB)

    Bellerud, Blane L.; Gunckel, Stephanie; Hemmingsen, Alan R.; Buchanan, David V.; Howell, Philip J.

    1997-10-01

    This study is part of a multi-year research project studying aspects of bull trout life history, ecology and genetics. This report covers the activities of the project in 1996. Results and analysis are presented in the following five areas: (1) analysis of the genetic structure of Oregon bull trout populations; (2) distribution and habitat use of bull trout and brook trout in streams containing both species; (3) bull trout spawning surveys; (4) summary and analysis of historical juvenile bull trout downstream migrant trap catches in the Grande Ronde basin; and (5) food habits and feeding behavior of bull trout alone and in sympatry with brook trout.

  15. Bull trout life history, genetics, habitat needs, and limiting factors in Central and Northeast Oregon. Annual report 1996

    International Nuclear Information System (INIS)

    This study is part of a multi-year research project studying aspects of bull trout life history, ecology and genetics. This report covers the activities of the project in 1996. Results and analysis are presented in the following five areas: (1) analysis of the genetic structure of Oregon bull trout populations; (2) distribution and habitat use of bull trout and brook trout in streams containing both species; (3) bull trout spawning surveys; (4) summary and analysis of historical juvenile bull trout downstream migrant trap catches in the Grande Ronde basin; and (5) food habits and feeding behavior of bull trout alone and in sympatry with brook trout

  16. Toxicity, distribution, accumulation and cooking loss of malathion in tissues of tilapia and common carp fishes

    Directory of Open Access Journals (Sweden)

    Hassan, I. M.

    1993-12-01

    Full Text Available The acute toxicity of malathion as an organophosphorus pesticide to both of the tested fish species, i.e. Tilapia nilotica (tilapia and cyprinus carpio (Common carp was followed by estimating the LC50 at intervals from 24h up to 96h. Tilapia was much more susceptible to malathion toxicity when compared with carp and the available data proved that the LG50 of malathion to common carp fish was 5-7 times the LC50 for tilapia. Accumulation of malathion pesticide in some organs (muscles, gills, intestine and liver of both fish species was studied after application of 200, 300 and 400 ppb malathion in water for 28 days. A proportional relation was found in the two fish species between exposure time and the applied concentrations. The rate of malathion accumulation was higher in liver followed by intestine and gills whereas the lowest concentration was found in muscles. Accumulated malathion in tilapia muscles was higher than carp; while a reversible trend was observed in most other organs. Cooking of the same fish species reduced effectively malathion content in their muscles. Frying of fish in oil lead to a higher loss percent of malathion than did the other methods of cooking.

    La toxicidad aguda de malatión, pesticida organofosforado, para las dos especies de pescado analizadas, Tilapia nilotica (tilapia y Cyprinus carpio (carpa común, fue seguida por estimación de la CL50 a intervalos desde las 24h hasta las 96h. Tilapia fue mucho más susceptible a la toxicidad del malatión cuando se comparó con carpa, y los datos disponibles proporcionaron que la CL50 del malatión para carpa común fue de 5-7 veces la GL50 para tilapia. La acumulación del pesticida malatión en algunos órganos (músculos, agallas, intestino e hígado de ambas especies de pescado fue estudiada después de la aplicación de concentraciones de 200, 300 y 400 ppb de malatión en agua durante 28 días. Se encontró una relaci

  17. Vulnerability to a small-scale commercial fishery of Lake Tana's (Ethiopia) endemic Labeobarbus compared with African catfish and Nile tilapia: An example of recruitment-overfishing?

    NARCIS (Netherlands)

    Graaf, de M.; Zwieten, van P.A.M.; Machiels, M.A.M.; Lemma, E.; Wudneh, T.; Dejen, E.; Sibbing, F.A.

    2006-01-01

    In 1986 a motorised, commercial gillnet fishery was introduced in Lake Tana, Ethiopia's largest lake (3050 km2) in addition to the artisanal, predominantly subsistence fishery conducted from reedboats. The three main species groups targeted by this fishery are a species flock of endemic, large Labeo

  18. The effect of nearly closed RAS on the feed intake and growth of Nile tilapia (Oreochromis niloticus), African catfish (Clarias gariepinus) and European eel (Anguilla anguilla)

    NARCIS (Netherlands)

    Mota, V.C.; Limbu, P.; Martins, C.I.; Eding, E.H.; Verreth, J.A.J.

    2015-01-01

    One of the challenges that Recirculating Aquaculture Systems (RAS) are still facing is the risk that in RAS fish grow less than in flow-through systems due to the accumulation of substances originating from feed, fish or bacteria associated with the water re-use. The present study investigated wheth

  19. Yellowstone Cutthroat 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 YELLOWSTONE CUTTHROAT TROUT contained in the StreamNet database. This feature class was created based...

  20. 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...

  1. Redband 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 REDBAND TROUT contained in the StreamNet database. This feature class was created based on linear...

  2. Lahontan Cutthroat 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 LAHONTAN CUTTHROAT TROUT contained in the StreamNet database. This feature class was created based on...

  3. Brown 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 BROWN TROUT contained in the StreamNet database. This feature class was created based on linear event...

  4. Westslope Cutthroat 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 WESTSLOPE CUTTHROAT TROUT contained in the StreamNet database. This feature class was created based...

  5. Great Smoky Mountains National Park Brook Trout Genetics

    Data.gov (United States)

    National Park Service, Department of the Interior — Great Smoky Mountains National Park (GRSM) is committed to monitoring ecological and evolutionary functions and processes of park ecosystems. Brook trout...

  6. Environmental contaminants in brook trout from Aroostook National Wildlife Refuge

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — In June 2012, four brook trout (Salvelinus fontinalis) were collected by angling from Chapman Pond and East Loring Lake at Aroostook NWR in northeast Maine. Two...

  7. Species status assessment report for the Rio Grande cutthroat trout

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The Rio Grande cutthroat trout (Oncorhynchus clarkii virginalis) lives in high elevation, coldwater streams in New Mexico and southern Colorado. It is a subspecies...

  8. Bull 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 BULL TROUT contained in the StreamNet database. This feature class was created based on linear event...

  9. Brook 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 BROOK TROUT contained in the StreamNet database. This feature class was created based on linear event...

  10. The growth of Sarotherodon (Tilapia) niloticus L. in Opa Reservoir, University of Ife, Ile-Ife, Nigeria

    OpenAIRE

    Arawomo, G.A.O.

    1983-01-01

    The growth of Sarotherodon (Tilapia) niloticus in Opa reservoir, University of Ife was determined from the fish scales. Compared with the growth in other similar water bodies the growth was comparatively faster in this newly-impounded reservoir

  11. Streptococcus iniae infection in cultured Asian sea bass (Lates calcarifer and red tilapia (Oreochromis sp. in southern Thailand

    Directory of Open Access Journals (Sweden)

    Kidchakan Supamattaya

    2010-08-01

    Full Text Available Streptococcal infections are becoming an increasing problem in aquaculture and have been reported worldwide in avariety of fish species. Here we describe the isolation and characterization of Streptococcus iniae from Asian sea bass (Latescalcarifer and red tilapia (Oreochromis sp. cultured in southern Thailand. Conventional and rapid identification systems,as well as the polymerase chain reaction (PCR, were used to determine that the isolate was S. iniae. The virulence of thisS. iniae was higher in Asian sea bass than in red tilapia, as shown by the 10 day-LD50 in Asian sea bass and red tilapia, being1.08x104 and 1.14x107 CFU, respectively. Histopathological changes in Asian sea bass are more severe than those observedin red tilapia. The changes can be found in several organs including liver, pancreas, heart, eye and brain. Histopathologicalfindings included cellular necrosis, infiltration of lymphocytes and granuloma formation in the infected organs.

  12. Differential pathogenicity of five Streptococcus agalactiae isolates of diverse geographic origin in Nile tilapia (Oreochromis niloticus L.)

    Science.gov (United States)

    Streptococcus agalactiae is an emerging pathogen of fish and has caused significant morbidity amd mortality worldwide. The work in this study assessed whether pathogenic differences exist among isolates from different geographic locations. Nile tilapia (Oreochromis niloticus L.) were administered an...

  13. Use, fate and ecological risks of antibiotics applied in tilapia cage farming in Thailand

    International Nuclear Information System (INIS)

    The use, environmental fate and ecological risks of antibiotics applied in tilapia cage farming were investigated in the Tha Chin and Mun rivers in Thailand. Information on antibiotic use was collected through interviewing 29 farmers, and the concentrations of the most commonly used antibiotics, oxytetracycline (OTC) and enrofloxacin (ENR), were monitored in river water and sediment samples. Moreover, we assessed the toxicity of OTC and ENR on tropical freshwater invertebrates and performed a risk assessment for aquatic ecosystems. All interviewed tilapia farmers reported to routinely use antibiotics. Peak water concentrations for OTC and ENR were 49 and 1.6 μg/L, respectively. Antibiotics were most frequently detected in sediments with concentrations up to 6908 μg/kg d.w. for OTC, and 2339 μg/kg d.w. for ENR. The results of this study indicate insignificant short-term risks for primary producers and invertebrates, but suggest that the studied aquaculture farms constitute an important source of antibiotic pollution. - Highlights: • First study assessing the risks of antibiotics applied in freshwater tilapia cages. • Ten antibiotics were reported to be used by tilapia cage farmers in two Thai rivers. • Peak oxytetracycline and enrofloxacin concentrations were in the order of μg/L. • Antibiotic concentrations in river sediments next to cages were up to several mg/kg. • Antibiotics are not posing a short-term risk for pelagic aquatic organisms. - Antibiotics applied in tilapia cage farming in Thailand are released into surrounding aquatic ecosystems and constitute an important source of environmental pollution

  14. Dopamine inhibits somatolactin gene expression in tilapia pituitary cells through the dopamine D2 receptors.

    Science.gov (United States)

    Jiang, Quan; Lian, Anji; He, Qi

    2016-07-01

    Dopamine (DA) is an important neurotransmitter in the central nervous system of vertebrates and possesses key hypophysiotropic functions. Early studies have shown that DA has a potent inhibitory effect on somatolactin (SL) release in fish. However, the mechanisms responsible for DA inhibition of SL gene expression are largely unknown. To this end, tilapia DA type-1 (D1) and type-2 (D2) receptor transcripts were examined in the neurointermediate lobe (NIL) of the tilapia pituitary by real-time PCR. In tilapia, DA not only was effective in inhibiting SL mRNA levels in vivo and in vitro, but also could abolish pituitary adenylate cyclase-activating polypeptide (PACAP)- and salmon gonadotropin-releasing hormone (sGnRH)-stimulated SL gene expression at the pituitary level. In parallel studies, the specific D2 receptor agonists quinpirole and bromocriptine could mimic the DA-inhibited SL gene expression. Furthermore, the D2 receptor antagonists domperidone and (-)-sulpiride could abolish the SL response to DA or the D2 agonist quinpirole, whereas D1 receptor antagonists SCH23390 and SKF83566 were not effective in this respect. In primary cultures of tilapia NIL cells, D2 agonist quinpirole-inhibited cAMP production could be blocked by co-treatment with the D2 antagonist domperidone and the ability of forskolin to increase cAMP production was also inhibited by quinpirole. Using a pharmacological approach, the AC/cAMP pathway was shown to be involved in quinpirole-inhibited SL mRNA expression. These results provide evidence that DA can directly inhibit SL gene expression at the tilapia pituitary level via D2 receptor through the AC/cAMP-dependent mechanism. PMID:26970582

  15. Molecular structure, distribution, and immunology function of TNFSF13B (BAFF) in Nile tilapia (Oreochromis niloticus).

    Science.gov (United States)

    Liu, Hongzhen; Zhang, Jiaxin; Li, Jianfeng; Song, Jinyun; Zhang, Shuangquan

    2016-04-01

    B cell-activating factor (BAFF)is a member of the tumor necrosis factor (TNF) family and plays roles in B cell survival and maturation. In this study, the full-length cDNA of Nile tilapia (Oreochromis niloticus) BAFF (tBAFF) was amplified from the spleen by reverse transcription PCR (RT-PCR). The open reading frame of this cDNA encodes a protein of 261 amino acids containing a predicted transmembrane domain and a furin protease cleavage site, similar to mammalian, avian, and reptile BAFF. Real-time quantitative PCR (qPCR) analysis revealed that tBAFF is present in various tissues and is predominantly expressed in the spleen. The predicted three-dimensional (3D) structure of the Nile tilapia (Oreochromis niloticus) soluble BAFF (tsBAFF) monomer was determined by (3D) structure modeling monomeranalyzed by (3D) structure mouse counterpart. Both tsBAFF and EGFP/tsBAFF were efficiently expressed in Escherichia coli BL21 (DE3), as confirmed by SDS-PAGE and Western blot analysis. After purification, the EGFP/tsBAFF fusion protein showed a fluorescence spectrum similar to that of EGFP. Laser scanning confocal microscopy showed that EGFP/tsBAFF bound to its receptor. In vitro, tsBAFF promoted the proliferation of Nile tilapia and mouse splenic B cells together with/without a priming agent (Staphylococcus aureus Cowan 1, SAC) or anti-mouse IgM. Furthermore, tsBAFF showed a similar proliferation-stimulating effect on mouse B cells compared to msBAFF. These findings indicate that tsBAFF plays an important role in the proliferation of Nile tilapia B cells and has functional cross-reactivity among Nile tilapia and mammals. Therefore, BAFF may represent a useful factor for enhancing immunological efficacy in animals. PMID:26915306

  16. Direct Ionic Regulation of the Activity of Myo-Inositol Biosynthesis Enzymes in Mozambique Tilapia.

    Directory of Open Access Journals (Sweden)

    Fernando D Villarreal

    Full Text Available Myo-inositol (Ins is a major compatible osmolyte in many cells, including those of Mozambique tilapia (Oreochromis mossambicus. Ins biosynthesis is highly up-regulated in tilapia and other euryhaline fish exposed to hyperosmotic stress. In this study, enzymatic regulation of two enzymes of Ins biosynthesis, Ins phosphate synthase (MIPS and inositol monophosphatase (IMPase, by direct ionic effects is analyzed. Specific MIPS and IMPase isoforms from Mozambique tilapia (MIPS-160 and IMPase 1 were selected based on experimental, phylogenetic, and structural evidence supporting their role for Ins biosynthesis during hyperosmotic stress. Recombinant tilapia IMPase 1 and MIPS-160 activity was assayed in vitro at ionic conditions that mimic changes in the intracellular milieu during hyperosmotic stress. The in vitro activities of MIPS-160 and IMPase 1 are highest at alkaline pH of 8.8. IMPase 1 catalytic efficiency is strongly increased during hyperosmolality (particularly for the substrate D-Ins-3-phosphate, Ins-3P, mainly as a result of [Na+] elevation. Furthermore, the substrate-specificity of IMPase 1 towards D-Ins-1-phosphate (Ins-1P is lower than towards Ins-3P. Because MIPS catalysis results in Ins-3P this results represents additional evidence for IMPase 1 being the isoform that mediates Ins biosynthesis in tilapia. Our data collectively demonstrate that the Ins biosynthesis enzymes are activated under ionic conditions that cells are exposed to during hypertonicity, resulting in Ins accumulation, which, in turn, results in restoration of intracellular ion homeostasis. We propose that the unique and direct ionic regulation of the activities of Ins biosynthesis enzymes represents an efficient biochemical feedback loop for regulation of intracellular physiological ion homeostasis during hyperosmotic stress.

  17. La Tilapia en el Perú: acuicultura, mercado, y perspectivas

    Directory of Open Access Journals (Sweden)

    Paúl M. Baltazar

    2013-05-01

    Full Text Available Tilapia es el nombre común con el cual se conocen a diversas especies de los géneros Oreochromis y Tilapia. Las Tilapias son peces de agua dulce endémicos y originarios de África y el Cercano Oriente, aprovechando sus características y adaptabilidad, a comienzos del siglo XIX se inician las investigaciones para utilizarlas en la piscicultura rural, especialmente en el Congo Belga (actualmente Zaire. A partir de 1924 se intensifica su cultivo en Kenia, sin embargo fue en el Extremo Oriente, en Malasia en donde se obtuvieron los mejores resultados y se iniciara su progresivo cultivo en diferentes partes del mundo. En Perú, en la década del 50, la Dirección General de Caza y Pesca del Ministerio de Fomento y Agricultura realizó las primeras introducciones con la especie Tilapia rendalli, utilizada como forraje para el paiche (Arapaina gigas; en la década de los 70, el IMARPE y la Universidad Nacional Agraria La Molina introdujeron las especies Oreochromis niloticus, Oreochromis hornorum y Oreochromis mossambica (Ramos y Gálvez, 2000, con fines de investigación y cultivo en las zonas de selva. La Tilapia roja, Oreochromis spp., ingresa a nuestro país entre los meses de octubre y noviembre de 1996, como parte complementaria de otro lote de reproductores grises, (con el objetivo de evitar la endogamia, procedentes de la Estación DIVISA, Panamá.

  18. Influence of environmental color on zootechnical performance and feeding behavior during masculinization of Nile tilapia

    Directory of Open Access Journals (Sweden)

    Perila Maciel Rebouças

    2014-10-01

    Full Text Available The rise of tilapia in Brazil and the world increasingly needs the best growing conditions. Despite the Nile tilapia has diurnal, your vision is considered a strong sensory stimulus, and as the perception of the color contrast of medium, production losses may be evidence due to stress caused too. Thus, an experiment was conducted at Biotechnology Aquaculture Applied Center (CEBIAQUA, The Fishing Engineering Department, Federal University of Ceará, with the aim of evaluating the influence of the background color translucent on zootechnical performance and feeding behavior of Nile tilapia during masculinization. We used 200 post-larvae (average weight = 0:02 ± 0.01g; mean initial length = 1.10 ± 0.01 cm of Nile tilapia, packed in 40 L aquarium, covered with cellophane, for 28 days. Fish were distributed in a completely randomized in two treatments (blue and green and five replications. Environmental variables analyzed were dissolved oxygen, temperature, pH and photoperiod and productive performance was evaluated weight, total length, condition factor and lot uniformity. Behavioral observations occurred twice daily, immediately before the first feeding and 2 minutes after each feeding treatment. We found no significant difference in water parameters in two treatments. The weight, length and condition factor did not differ between treatments. There was a higher survival rate, more lot uniformity, and an obvious grouped behavior during feeding in aquaria translucent greens than blues. So for the masculinization of Nile tilapia, it is recommended to translucent green, because the results were most satisfactory.

  19. Tilapia rendalli increases phytoplankton biomass of a shallow tropical lake

    Directory of Open Access Journals (Sweden)

    Lúcia Helena Sampaio da Silva

    2014-12-01

    Full Text Available AIM: This study aimed to experimentally test the influence of a planktivorous filter-feeding fish (Tilapia rendalli on the phytoplankton dynamics of a small and shallow tropical reservoir (Lake Monte Alegre, Brazil. Adults of T. rendalli of this lake feed preferentially on phytoplankton, and we hypothesize that: I adults of T. rendalli will decrease the phytoplankton biomass and composition through direct herbivory, and II as it is a eutrophic system, fish would not have strong influence on phytoplankton through nutrient cycling. METHODS: To evaluate these different effects on algae, a field experiment was performed in the summer period for 15 days, in mesocosms isolated from the sediment, using a control group (no fish and a treatment group (with one fish in each mesocosm. Physical and chemical variables and phyto- and zooplankton were evaluated at the start, middle, and end of the experiment. RESULTS: At the end of the experiment, it was observed a significant increase in ammonium concentrations and total phytoplankton biomass, Cyanobacteria and Zygnemaphyceae and all size classes except class II (20-30 µm in the treatment group (with fish. The biomass increase of the potentially toxic cyanobacterium Cylindrospermospsis raciborskii was also observed in the fish treatment at the end of the experimental period. CONCLUSION: This study did not support both initial hypotheses. It supports the assertion that in tropical water bodies, with similar characteristics to the environment studied, planktivorous filter-feeding fish, such as T. rendalli, are not effective in reducing phytoplankton biomass through direct grazing, even when phytoplankton is one of their main food items. T. rendalli can contribute to the increase of phytoplankton biomass and can promote or increase the eutrophication of aquatic systems.

  20. Radiation decontamination and disinfestation of salted dried tilapia fish (Koobi)

    International Nuclear Information System (INIS)

    Salted dried tilapia (Oreochromis niloticus) fish locally called koobi was investigated with the view of establishing the effective radiation dose for controlling microbial and insect activity on the product. Total viable count (TVC) of market samples of koobi ranged between log 10 4.11 - 6.78 cfu/g, whilst mould and yeast count ranged between log10 1.38-3.38 cfu/g. Staphylococcus aureus counts ranged between log10 2.85 - 4.15 cfu/g. After 4 weeks storage under ambient conditions, total viable count increased to log10 7.5 ± 2.5 cfu/g. Significant reduction in total viable count was observed after treatment with gamma radiation. A least square regression fitted through the data points indicated that 1.3 kGy would be required to reduce the microbial population on the product by one log cycle. Insects and pink colonies of halophilic bacteria were observed on all the nonirradiated samples after 4 weeks storage. Treatment with 3 kGy gamma radiation eliminated all insect forms, while microbial population was controlled with TVC ranging between log10 1.9 ± 1.1 and log10 10 2.7 ± 1.6 cfu/g throughout the 16 weeks storage period. The proliferation of halophilic bacteria and subsequent appearance of pink colonies on irradiated koobi was suppressed until the 16th week. Irradiation, therefore, extended the shelf-life of koobi from 4 to 15 weeks. (au)

  1. 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).

  2. Food Intake and Feed Conversion Ratios in Abant Trout (Salmo trutta abanticus T., 1954) and Rainbow Trout (Oncorhynchus mykiss W., 1792) in Pond Culture

    OpenAIRE

    UYSAL, İrfan

    2002-01-01

    This study was carried out at DSI-Gölköy Fish Production Station in Bolu and lasted for 350 days. Food consumption (FC) and feed conversion ratios (FCR) in Abant and rainbow trout in pond culture were compared. Abant trout larvae obtained from eggs of wild Abant trout broodstocks in Lake Abant and rainbow trout larvae obtained from eggs of the cultured broodstocks in Gölköy Fish Production Station were used in this study. Trial I involved 4 groups (2 Abant and rainbow trout experimental gr...

  3. Comparison of the Growth Performance and Mortality in Abant Trout (Salmo trutta abanticus Tortonese, 1954) and Rainbow Trout (Oncorhynchus mykiss Walbaum, 1792) under Farming Conditions

    OpenAIRE

    UYSAL, İrfan

    2002-01-01

    This experiment was conducted between 15th February 2000 (day 1) and 31st January 2001 (day 350) at the DSI-Gölköy Fish Production Station, Bolu (Turkey). Abant trout larvae obtained from eggs of wild Abant trout broodstocks in Lake Abant and rainbow trout larvae obtained from eggs of the hatchery broodstocks in Gölköy Fish Production Station were used. Trials I and II involved eight groups (four Abant and rainbow trout experimental groups, and four Abant and rainbow trout parallel groups). A...

  4. Effects of trout bradykinin on the motility of the trout stomach and intestine: evidence for a receptor distinct from mammalian B1 and B2 subtypes

    OpenAIRE

    Jensen, Jorgen; J. Michael Conlon

    1997-01-01

    Trout bradykinin ([Arg0,Trp5,Leu8]-bradykinin; trout BK), recently isolated from kallikrein-treated trout plasma, produced sustained and concentration-dependent contractions of isolated longitudinal muscle from rainbow trout stomach (pD2=7.01±0.03) and proximal small intestine (pD2=7.37±0.07). The maximum responses were 85±2% (stomach) and 101±35% (intestine) of the corresponding responses to 10−5 M acetylcholine. Strips of circular smooth muscle from trout stomach and intestine did not contr...

  5. Eggs Incubation, Early Development and growth in Frys of Brown Trout (Salmo trutta macrostigma) and Black Sea Trout (Salmo trutta labrax)

    OpenAIRE

    Ahmet ALP; Erer, Mesut; KAMALAK, Adem

    2010-01-01

    Some of the embryonic development stages and growth of the frys of brown trout (Salmo trutta macrostigma) and Black Sea trout (Salmo trutta labrax) were examined. The first eye pigmentation in the brown trout eggs were realised on the 35 days (244 day-degree) at 7.23°C and 31 days (260 day-degree) at 8.21°C post fertilisation. First eye pigmentation of the Black Sea trout eggs were seen on day 25 (215 day-degree) at 8.21°C. Brown trout larvae were hatched on day 56 (387 day-degree) at 7.23°C ...

  6. Influence of good manufacturing practices on the shelf life of refrigerated fillets of tilapia (Oreochromis niloticus) packed in modified atmosphere and gamma-irradiated

    OpenAIRE

    Monteiro, Maria Lúcia Guerra; Mársico, Eliane Teixeira; Mano, Sérgio Borges; Teixeira, Claudia Emília; da Cruz Silva Canto, Anna Carolina Vilhena; de Carvalho Vital, Helio; Conte-Júnior, Carlos Adam

    2013-01-01

    This study evaluated the influence of good manufacturing practices (GMP) on the shelf life of refrigerated fillets of Nile tilapia (Oreochromis niloticus) packed in modified atmosphere packaging (MAP) and irradiated. In a first series of experiments, 120 tilapia fillets kept under controlled sanitary conditions were purchased from a fish market managed by a cooperative. A second lot totaling 200 tilapia fillets was obtained under controlled storage conditions from a pilot plant. The combined ...

  7. Salinity on artificial reproduction of silver catfish (Rhamdia quelen

    Directory of Open Access Journals (Sweden)

    Gabriel Bernardes Martins

    2015-03-01

    Full Text Available Attempting to improve reproduction performance and ichthyo prophylaxis, this study evaluated the effects of maintaining silver catfish (Rhamdia quelen broodstock in different saline concentrations (0, 2, 4, 6 and 8‰ on gametes quality and reproductive viability. The results showed that sperm percent motility did not change between 0 and 4‰, but it was reduced at 6‰, and sperm became immotile at 8‰ salinity. Sperm motility time was increased (almost five fold at 6‰. Salinities up to 4‰ prevented fertilization and hatching, proving their deleterious effects on oocytes and embryos. Therefore, media up to 4‰ salinity may be an alternative for icthyo prophylaxis, although fertilization and incubation must be done in freshwater medium

  8. Physiological responses of Chinese longsnout catfish to water temperature

    Science.gov (United States)

    Han, Dong; Xie, Shouqi; Zhu, Xiaoming; Yang, Yunxia

    2011-05-01

    We evaluated the effect of water temperature on the growth and physiology of the Chinese longsnout catfish ( Leiocassis longirostris Günther). The fish were reared at four temperatures (20, 25, 30, and 35°C) and sampled on days 7, 20, and 30. We measured plasma levels of insulin, free thyroxine (FT4), free 3,5,3'-triiodothyronine (FT3), lysozyme and leukocyte phagocytic activity. The optimum water temperature for growth was 27.7°C. The plasma levels of insulin and FT4 declined significantly ( P<0.05) on day 30 at temperatures above 20°C. Lysozyme activity was significantly ( P<0.05) lower at 25°C than at other temperatures. We conclude that final weight, insulin, FT4, and lysozyme were significantly affected by water temperature.

  9. Brown trout redd superimposition in relation to spawning habitat availability

    OpenAIRE

    Gortázar Rubial, Javier; Alonso González, Carlos; García de Jalón Lastra, Diego

    2012-01-01

    The relationship between redd superimposition and spawning habitat availability was investigated in the brown trout (Salmo trutta L.) population inhabiting the river Castril (Granada, Spain). Redd surveys were conducted in 24 river sections to estimate the rate of redd superimposition. Used and available microhabitat was evaluated to compute the suitable spawning habitat (SSH) for brown trout. After analysing the microhabitat characteristics positively selected by females, SSH was defined as ...

  10. Long-term brown trout populations responses to flow manipulation

    OpenAIRE

    SABATON C.; Souchon, Y.; Capra, H.; Gouraud, V.; LASCAUX J. M.; Tissot, L.

    2008-01-01

    Despite the many habitat simulations that have been undertaken around the world, not enough biological monitoring has been performed following flow manipulations. It is difficult, however, to refine flow management decisions without a better understanding of the links between amounts, durations and seasonality of flow deliveries and population dynamics. Trout populations were monitored before and after flow alterations in five trout streams, involving 17 study sites over a 4- to 12-year perio...

  11. Brown trout population dynamics versus long term habitat history

    OpenAIRE

    Capra, H.; Souchon, Y.; Lamouroux, N.

    2004-01-01

    The influence of stream discharge and habitat suitability history was investigated over 12 years on three natural brown trout (Salmo trutta) population dynamics. Discharge and habitat (described by Weighted Usable Area, WUA) variability during three "bottleneck" periods of population dynamics (spawning, fry, and summer) were used to explain variability of trout age-class densities (young of the year, juveniles, and adults). Discharge and WUA variability for each period was described with mean...

  12. SuchThatCast Episode 3: J.D. Trout

    OpenAIRE

    Søraker, J.H.

    2012-01-01

    SuchThatCast goes mobile in the third episode, as I interview J.D. Trout on the appr. 2 hour train ride between Enschede and Schiphol airport. Trout received his PhD in Philosophy at Cornell University and is currently Professor of Philosophy and Psychology at Loyola University Chicago. He was recently awarded the prestigious Phi Beta Kappa Romanell Professorship for 2012-13. His chief interests include the nature of scientific explanation, the psychology of human judgment, scientific realism...

  13. Evolutionary Genetics of Rainbow Trout, Parasalmo gairdnerii (Richardson)

    OpenAIRE

    Berg, William J.

    1987-01-01

    Starch-gel electrophoresis was used to obtain allozyme data from 114 populations of rainbow-series trout. Seventy-three alleles were segregating at 24 genetic loci. An additional seven loci were monomorphic in all populations. Eight genetically discrete intraspecific population-groups were identified and formal nomenclatural recognition of their subspecific status was suggested. The widespread coastal rainbow trout subspecies, Parasalmo gairdnerii gairdnerii was found to have higher levels of...

  14. Dominance of introduced Nile tilapia, Oreochromis niloticus (L.) in Lake Victoria: A case of changing biology and ecosystem

    OpenAIRE

    Njiru, M.; Ojuok, J.E.; Getabu, A.; Muchiri, M.S.; Cowx, I. G.; Okeyo Owuor, J.B.

    2006-01-01

    Nile tilapia, Oreochromis niloticus together with other tilapiines of Oreochromis leucosticus, Tilapia zillii and Sarotherodon melanopleudra (=T. rendalii) were introduced into Lake Victoria (Kenya) between 1951 and 1962 to boost the then declining fishery. Only O. niloticus was able to establish leading further to reduction in endemic tilapiines of Oreochromis variabilis and Oreochromis esculentus. O. niloticus currently forms the third commercially important species after introduced Nile pe...

  15. Management measures to control diseases reported by tilapia (Oreochromis spp.) and whiteleg shrimp (Litopenaeus vannamei) farmers in Guangdong, China

    DEFF Research Database (Denmark)

    Li, Kang; Liu, Liping; Clausen, Jesper Hedegaard;

    2016-01-01

    Culture of tilapia (Oreochromis spp.) and whiteleg shrimp (Litopenaeus vannamei) has intensified during the last decade in China with increased production, meanwhile it has also brought some problems, including diseases, increased use of antimicrobials and other chemicals for disease control...... production area in China. Tilapia farmers (25) mainly reported streptococcosis (9) and exophthalmia disease (9) which often was treated with sulfadiazine, florfenicol and vitamins or rhubarb (Rheum rhabarbarum) extract, although farmers thought the effectiveness of antimicrobial treatment has decreased...

  16. A comparative study on growth, composition and sensory quality between farmed and wild Nile tilapia (Oreochromis niloticus)

    OpenAIRE

    Mary N. Muchiri; Jackin N. Nanua; David Liti

    2015-01-01

    This study was conducted at Moi University, Kenya, to investigate the effect of fish diets on growth, chemical composition and organoleptic quality of farmed Nile tilapia (Oreochromis niloticus), and compared with wild tilapia from Lake Victoria. Fish were grown for six months in triplicates using three feeds: (i) maize bran, (ii) formulated diet containing maize bran, freshwater shrimp, soya bean and cotton seed cake and (iii) control without supplemental feed. Fish were weighed fortnightly,...

  17. The Effect of Dietary Phytase Supplementation and Incubation in Soy Protein Concentrate based diet Fed to Nile Tilapia

    OpenAIRE

    Xue, Yuhang

    2015-01-01

    Aquatic feed require high quality, low cost nutrients with increasing aquaculture production. Tilapia has become the third most important cultured fish species in the world, just after salmonids and carps. Soybean and its products are the most popular source of plant protein in compound aquatic feeds. In the existing plant protein sources phytate-P absorption and digestion is low in Nile Tilapia. This experiment aimed to investigate the different effects on retention and utilization o...

  18. Effect of phosphorous supplementation in the formulated fish feed on carcass quality of Nile tilapia Oreochromis niloticus L.

    OpenAIRE

    Sarkar, M.R.U.; Yakupitiyage, A.; Lin, C.K.; Little, D.C.

    2004-01-01

    A study was conducted to evaluate the effect of phosphorus supplementation in the formulated fish diet on carcass quality of Nile tilapia in net-cages suspended in fertilized earthen ponds. In the experiment 3% di-calcium phosphate (DCP), 3% triple supper phosphate (TSP) and 7% 16:20 inorganic fertilizer were added as phosphorous sources to three diets containing fish meal as main protein ingredient. Feeding tilapia in net-cages with these diets significantly (p

  19. Application of Probiotic, Prebiotic and Synbiotic for the Control of Streptococcosis in Tilapia Oreochromis niloticus

    OpenAIRE

    . Widanarni; Tanbiyaskur

    2015-01-01

    One of the fish diseases that is becoming the main problem in tilapia culture is streptococcosis caused by Streptococcus agalactiae. Application of probiotic, prebiotic and synbiotic are expected to be an alternative for controlling the disease. The purpose of this study was to examine the effectiveness of the administration of probiotic, prebiotic and synbiotic through artificial feed to control streptococcosis in tilapia. This study consisted of five treatments with three replications, name...

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

    Science.gov (United States)

    Evenhuis, Jason P; LaFrentz, Benjamin R

    2016-08-01

    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. PMID:27503917

  1. Seasonal movement of brown trout in the Clinch River, Tennessee

    Science.gov (United States)

    Bettinger, J.M.; Bettoli, P.W.

    2004-01-01

    We used radiotelemetry to monitor the seasonal movements of trophy-size brown trout Salmo trutta in the Clinch River below Norris Dam, Tennessee, to determine whether establishing a special-regulation reach to reduce fishing mortality was a viable management option. Fifteen brown trout (size range, 430-573 mm total length) collected from the river were implanted with radio transmitters between November 1997 and May 1998. Forty-seven percent of these fish died or expelled their transmitters within 50 d postsurgery. The range of movement for surviving brown trout was significantly larger in fall (geometric mean range = 5,111 m) than in any other season. Four brown trout that were monitored for more than 1 year exhibited a limited range of movement (5 km) during the fall season, presumably to spawn. Brown trout also moved more during the fall than in any other season. Harvest restrictions applied to a specific reach of the Clinch River would reduce the exploitation of brown trout in that reach for most of the year but not during the fall, when many fish undertake extensive spawning migrations.

  2. The Holocene occurrence of the European catfish (Silurus glanis) in Belgium: the archaeozoological evidence

    OpenAIRE

    Van Neer, W.; Ervynck, A.

    2009-01-01

    An overview is given of the skeletal remains of the European catfish Silurus glanis found thus far in Belgian archaeological sites. These finds demonstrate that the species is autochthonous and allow documenting its occurrence and disappearance during the Holocene in the Scheldt and Meuse basins. Possible causes for the local extinction of this catfish are discussed.

  3. Ribosomal protein genes are highly enriched among genes with allele-specific expression in the interspecific F1 hybrid catfish.

    Science.gov (United States)

    Chen, Ailu; Wang, Ruijia; Liu, Shikai; Peatman, Eric; Sun, Luyang; Bao, Lisui; Jiang, Chen; Li, Chao; Li, Yun; Zeng, Qifan; Liu, Zhanjiang

    2016-06-01

    Interspecific hybrids provide a rich source for the analysis of allele-specific expression (ASE). In this work, we analyzed ASE in F1 hybrid catfish using RNA-Seq datasets. While the vast majority of genes were expressed with both alleles, 7-8 % SNPs exhibited significant differences in allele ratios of expression. Of the 66,251 and 177,841 SNPs identified from the datasets of the liver and gill, 5420 (8.2 %) and 13,390 (7.5 %) SNPs were identified as significant ASE-SNPs, respectively. With these SNPs, a total of 1519 and 3075 ASE-genes were identified. Gene Ontology analysis revealed that genes encoding cytoplasmic ribosomal proteins (RP) were highly enriched among ASE genes. Parent-of-origin was determined for 27 and 30 ASE RP genes in the liver and gill, respectively. The results indicated that genes from both channel catfish and blue catfish were involved in ASE. However, each RP gene appeared to be almost exclusively expressed from only one parent, indicating that ribosomes in the hybrid catfish were in the "hybrid" form. Overall representation of RP transcripts among the transcriptome appeared lower in the F1 hybrid catfish than in channel catfish or blue catfish, suggesting that the "hybrid" ribosomes may work more efficiently for translation in the F1 hybrid catfish. PMID:26747053

  4. Dioxin congener patterns in commercial catfish from the United States and the indication of mineral clays as the potential source

    Science.gov (United States)

    Since 1991 the U.S. Department of Agriculture (USDA) has conducted annual surveys of pesticide residues in foods under the Agricultural Marketing Service’s Pesticide Data Program (PDP). To assess chemical residues in domestically marketed catfish products, 1479 catfish samples were collected during ...

  5. Molecular and morphological characterization of myxozoan actinospore types from a commercial catfish pond in the Mississippi Delta

    Science.gov (United States)

    The actinospore diversity of infected Dero digitata was surveyed (May, 2011) from a channel catfish production pond in the Mississippi Delta region for the elucidation of unknown myxozoan life cycles. Only two myxozoan life cycles have been molecularly confirmed in channel catfish (Ictalurus puncta...

  6. Feeding Lactobacillus spp. and Bacillus spp. Does Not Improve Growth or Survival of Channel Catfish Experimentally Challenged with Edwardsiella ictaluri

    Science.gov (United States)

    A major problem in the channel catfish industry has been high disease loss to enteric septicemia of catfish, caused by the bacterium Edwardsiella ictaluri. Feeding probiotics may prove beneficial in improving disease resistance. The first study examined the effects of a Lactobacillus probiotic (Flor...

  7. Increasing Fish Oil Levels in Commercial Diets Influence Hematology and Immune Responses of Channel Catfish, Ictalurus punctatus

    Science.gov (United States)

    Cultured freshwater fish including channel catfish are commonly fed grain-soybean meal based feeds high in linoleic series (n-6) fatty acids. Published studies have shown that supplementation of catfish diets with marine fish oil rich in n-3 highly unsaturated fatty acids (n-3 HUFA) significantly in...

  8. Implication of lateral genetic transfer in the emergence of Aeromonas hydrophila isolates of epidemic outbreaks in channel catfish

    Science.gov (United States)

    Background: A recent epidemic outbreak of motile Aeromonas septicemia of catfish caused by highly virulent Aeromonas hydrophila is a major threat to the catfish industry in the southeastern United States. The lack of a complete genome sequence for this newly emerged A. hydrophila genotype hampers ef...

  9. Evaluation of corn distillers dried grains with solubles and brewers yeast in diets for channel catfish Ictalurus punctatus

    Science.gov (United States)

    A study was conducted to examine the use of distillers grains with solubles (DDGS), ethanol extracted DDGS (EDDGS), and brewers yeast in channel catfish, Ictalurus punctatus, diets. Diets containing these ingredients were compared with all-plant and fish meal control diets. Juvenile channel catfish ...

  10. Evaluation of potassium permanganate against an experimental subacute infection of Flavobacterium columnare in channel catfish, Icatlurus punctatus

    Science.gov (United States)

    The efficacy of potassium permanganate (KMnO4) as a prophylactic and therapeutic treatment for subacute infection of Flavobacterium columnare was demonstrated in experimentally infected channel catfish, Ictalurus punctatus. Catfish experimentally infected with F. columnare to mimic a subacute infec...

  11. Effects of Various Corn Distillers By-products on Growth and Feed Efficiency of Channel Catfish, Ictalurus punctatus

    Science.gov (United States)

    A study was conducted to examine the use of corn distillers by-products in diets and the effects of additional dietary fat on channel catfish, Ictalurus punctatus, performance. Juvenile channel catfish (initial weight: 12.6 g per fish) were stocked in flow-through aquaria and fed one of six practica...

  12. Apolipoprotein A1 in channel catfish: Transcriptional analysis, antimicrobial activity, and efficacy as plasmid DNA immunostimulant against Aeromonas hydrophila infection

    Science.gov (United States)

    The objectives of this study were to: 1) determine transcriptional profiles of apolipoprotein A1 (ApoA1) in collected channel catfish tissues after infection with A. hydrophila by bath immersion; 2) investigate whether recombinant channel catfish apolipoprotein A1 produced in E. coli expression syst...

  13. Recombinant goose-type lysozyme in channel catfish: lysozyme activity and efficacy as plasmid DNA immunostimulant against Aeromonas hydrophila infection

    Science.gov (United States)

    The objectives of this study were: 1) to investigate whether recombinant channel catfish lysozyme g (CC-Lys-g) produced in E. coli expression system possesses any lysozyme activity; and 2) to evaluate whether channel catfish lysozyme g plasmid DNA could be used as an immunostimulant to protect chann...

  14. 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...

  15. Reproductive isolation and genetic differentiation of ferox trout from sympatric brown trout in Loch Aweand Loch Laggan, Scotland

    OpenAIRE

    Duguid, A.; Prodohl, Paulo; Ferguson, A.

    2006-01-01

    Molecular marker studies reported here, involving allozymes, mitochondrial DNA and microsatellites, demonstrate that ferox brown trout Salmo trutta in Lochs Awe and Laggan, Scotland, are reproductively isolated and genetically distinct from co-occurring brown trout. Ferox were shown to spawn primarily, and possibly solely, in a single large river in each lake system making them particularly vulnerable to environmental changes. Although a low level of introgression seems to have occurred with ...

  16. Factors influencing the distribution of brown trout (Salmo trutta) in a mountain stream: Implications for brown trout invasion success

    OpenAIRE

    Meredith, Christy

    2012-01-01

    Brown trout (Salmo trutta), one of the world’s most successful introduced species, negatively impacts native aquatic communities through predation, competition, and ecosystemlevel effects. Thus, there is a need to understand factors controlling the distribution of exotic brown trout in river systems, in order to prioritize and develop conservation and management strategies. Within the context of invasion success, I investigated how the physical template of the Logan River influences the distr...

  17. Micro-scale distribution of brown trout: an opportunity for kin selection?

    DEFF Research Database (Denmark)

    Carlsson, J.; Carlsson, J.E.L.

    2002-01-01

    Fourteen microsatellite loci were used to analyse the degree of relatedness between and within cohorts of stream-living brown trout (Salmo trutta L.). Differences in degree of relatedness were found between cohorts with mature and older having the highest intracohort relatedness. The higher genetic...... relatedness among the mature and older trout is interpreted as indications of clustering of related mature and older trout prior to spawning in the vicinity of spawning grounds. Young-of-the-year trout showed a lower degree of association with related trout of the same cohort than did mature and older trout....... It is argued that the clustering of mature and older trout may facilitate kin selection and that the low degree of association among related young-of-the-year trout could be explained by juvenile fish avoiding competition for territories with related individuals...

  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. A first generation BAC-based physical map of the channel catfish genome

    Directory of Open Access Journals (Sweden)

    Waldbieser Geoffrey C

    2007-02-01

    Full Text Available Abstract Background Channel catfish, Ictalurus punctatus, is the leading species in North American aquaculture. Genetic improvement of catfish is performed through selective breeding, and genomic tools will help improve selection efficiency. A physical map is needed to integrate the genetic map with the karyotype and to support fine mapping of phenotypic trait alleles such as Quantitative Trait Loci (QTL and the effective positional cloning of genes. Results A genome-wide physical map of the channel catfish was constructed by High-Information-Content Fingerprinting (HICF of 46,548 Bacterial Artificial Chromosomes (BAC clones using the SNaPshot technique. The clones were assembled into contigs with FPC software. The resulting assembly contained 1,782 contigs and covered an estimated physical length of 0.93 Gb. The validity of the assembly was demonstrated by 1 anchoring 19 of the largest contigs to the microsatellite linkage map 2 comparing the assembly of a multi-gene family to Restriction Fragment Length Polymorphism (RFLP patterns seen in Southern blots, and 3 contig sequencing. Conclusion This is the first physical map for channel catfish. The HICF technique allowed the project to be finished with a limited amount of human resource in a high throughput manner. This physical map will greatly facilitate the detailed study of many different genomic regions in channel catfish, and the positional cloning of genes controlling economically important production traits.

  20. Mitochondrial phylogeny and phylogeography of East African squeaker catfishes (Siluriformes: Synodontis

    Directory of Open Access Journals (Sweden)

    Meyer Axel

    2006-06-01

    Full Text Available Abstract Background Squeaker catfishes (Pisces, Mochokidae, Synodontis are widely distributed throughout Africa and inhabit a biogeographic range similar to that of the exceptionally diverse cichlid fishes, including the three East African Great Lakes and their surrounding rivers. Since squeaker catfishes also prefer the same types of habitats as many of the cichlid species, we hypothesized that the East African Synodontis species provide an excellent model group for comparative evolutionary and phylogeographic analyses. Results Our analyses reveal the existence of six major lineages of Synodontis in East Africa that diversified about 20 MYA from a Central and/or West African ancestor. The six lineages show a clear geographic patterning. Two lineages are endemic to Lake Tanganyika (plus one non-endemic representative, and these are the only two Synodontis lineages that diversified further into a small array of species. One of these species is the cuckoo catfish (S. multipunctatus, a unique brood parasite of mouthbrooding haplochromine cichlids, which seems to have evolved in parallel with the radiation of its cichlid host lineage, the Tropheini. We also detect an accelerated rate of molecular evolution in S. multipunctatus, which might be the consequence of co-evolutionary dynamics. Conclusion We conclude that the ancestral lineage of today's East African squeaker catfish fauna has colonized the area before the Great Lakes have formed. This ancestor diversified rapidly into at least six lineages that inhabit lakes and rivers in East Africa. Lake Tanganyika is the only lake harboring a small species flock of squeaker catfishes.