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Sample records for cultured nile tilapia

  1. Edwardsiella ictaluri as the causative agent of mortality in cultured Nile tilapia

    Science.gov (United States)

    Edwardsiella ictaluri was consistently isolated from the spleens, livers, and head kidneys of diseased Nile tilapia Oreochromis niloticus from a farm experiencing mortality events in several culture ponds. We describe the first published outbreak of E. ictaluri–induced Edwardsiellosis in Nile tilapi...

  2. Growth of Mixed-Sex and Monosex Nile Tilapia in Different Culture Systems.

    OpenAIRE

    Chakraborty, Suman Bhusan; , Debasis Mazumdar; , Urmi Chatterji; , Samir Banerjee

    2011-01-01

    Growth of 17α-methyltestosterone treated monosex Nile tilapia, Oreochromis niloticus was compared with hormone untreated mixed-sex fish in four different culture systems. The experiment had 2 X 4 factorial design: the first factor was presence or absence of hormone treatment (monosex and mixed-sex fish), the second factor was related to culture system (cistern, flow-through, pen and pond). Fish were cultured under similar feeding regime and stock...

  3. 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.

  4. Seasonal influence on the hematological parameters in cultured Nile tilapia from southern Brazil

    Directory of Open Access Journals (Sweden)

    GT. Jerônimo

    Full Text Available This study evaluated seasonality in hematological parameters of Nile tilapia cultured in the state of Santa Catarina, southern Brazil. A total of 240 fish were examined during four seasons between April 2007 and March 2008 in three different fish farms. After being anesthetised in a benzocaine solution, blood samples were withdrawn into syringes containing a drop of 10% EDTA for hematological analysis. The results were compared between fish farms and seasons, which are well delimited in southern Brazil. In a traditional fish farm in Joinville in the summer, there was an increase in the percentage of hematocrit and in the red blood cell count. The highest values of total leukocytes were found in fish from fee-fishing in Blumenau in the autumn while the lowest values occurred in those from swine consorted system in Ituporanga in the summer. Thrombocytosis was observed in the autumn, and lymphocytosis was found in both the autumn and winter in tilapia from all fish farms investigated. Neutrophilia was only observed in winter and autumn in fish from Blumenau and Ituporanga. This work demonstrated the influence of seasonality and the handling characteristics of each fish farm on certain hematological parameters in Nile tilapia.

  5. Association between periphyton and bioflocs systems in intensive culture of juvenile Nile tilapia

    Directory of Open Access Journals (Sweden)

    Davi de Holanda Cavalcante

    2016-05-01

    Full Text Available The present work aimed at determining the effects of the association between the periphyton-based system with the bioflocs-based system in the intensive culture of juvenile Nile tilapia (1.56 ± 0.07 g; 72 fish m-3, on variables of water quality, growth performance and effluent quality after 10 weeks. The experiment was arranged in a 2 x 2 factorial randomized block design with four treatments and five repetitions each. The factors tested were the following: ‘underwater structure’ (absence and presence and ‘adjustment of the C: N ratio of water’ (no and yes. The final fish body weight, specific growth rate and yield were higher (p < 0.05 in the C: N-adjusted tanks. The presence of submerged structures in the tanks had no significant influence on those same variables. It was concluded that the periphyton-based system is not indicated for intensive farming of Nile tilapia, in which there is a high allowance of artificial feed to fish.

  6. Fishborne trematodes in cultured Nile tilapia (Oreochromis niloticus) and wild-caught fish from Thailand

    DEFF Research Database (Denmark)

    Wiriya, Benjamaporn; Clausen, Jesper Hedegaard; Inpankaew, Tawin

    2013-01-01

    was to determine the prevalence of FZT metacercarial infections in Nile tilapia from cage and pond aquaculture systems and in wild-caught fish from Suphan Buri, Nakhon Pathom and Chachoengsao provinces, Thailand. Fish were collected from four cages in Suphan Buri and four ponds in Nakhon Pathom provinces between...... September-October 2011 and April-May 2012 and wild-caught fish were collected in May 2012. All fish were examined for metacercariae by a pepsin digestion and metacercariae identified using morphological and molecular methods. During the first sampling of tilapia the prevalence of metacercariae in cage...... falcatus, Haplorchis pumilio and Procerovum varium. The results revealed a low risk for FZT in Nile tilapia cultured in cage and pond aquaculture systems. However, the high prevalence of FZT in wild-caught fish indicates a high potential for spillover from wild reservoir hosts and underscores the need...

  7. Protozoan and metazoan parasites of Nile tilapia Oreochromis niloticus cultured in Brazil

    Directory of Open Access Journals (Sweden)

    Wanderson Pantoja MF

    2012-04-01

    Full Text Available Objective. This study describes the parasitic fauna and relative condition factor (Kn in Nile tilapia Oreochromis niloticus L. (Cichlidae from fish farms in the State of Amapá. Material and methods. 123 fish from four fish farms in the state of Amapá, Brazil were necropsied for parasitological and Kn analysis. Results. 64.2% of the examined fish, had the gills infected with Cichlidogyrus tilapiae Paperna, 1960 (Monogenoidea: Dactylogyridae; Ichthyophthirius multifiliis Fouquet, 1876 (Protozoa: Ciliophora, Trichodina Ehrenberg, 1830 and Paratrichodina africana Kazubski & El-Tantawy, 1986 (Protozoa: Trichodinidae. The highest prevalence found corresponded to Monogenoidea C. tilapiae while the lowest corresponded to Trichodinidae. However, I. multifiliis was the parasite that presented the greatest intensity and abundance. The differences found in the infection rates of the different fish farms due to causes further discussed. The parasitism did not influence the relative condition factor (Kn of fish. This was the first record of P. africana in Brazil and occurred in the Eastern Amazon. Conclusions. In Brazil, Lamproglena sp. is an emerging parasite in the Southern and Southeastern regions, but this crustacean was not found in the Nile tilapia in the State of Amapá. The parasitic infections in Nile tilapia farmed in Brazil are caused by protozoan, monogenoidea, crustacea and digenea species, and the regional differences on their prevalence and intensity rates are discussed in this study.

  8. Simulation of Nile tilapia (Oreochromis niloticus niloticus L.) culture in ponds, through individual-based modelling, using a population dynamic approach

    NARCIS (Netherlands)

    Graaf, de G.J.; Dekker, P.J.; Huisman, E.A.; Verreth, J.A.J.

    2005-01-01

    A simulation model for the production of the Nile tilapia (Oreochromis niloticus niloticus L.) for mixed- or mono-sex culture and for poly-culture with the African catfish (Clarias gariepinus Burchell 1822) or African snakehead (Parachanna obscura Günther 1861) is presented. The model is based on an

  9. 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

    calculated emissions of 2,105,118 and 34,904 Population Equivalents (PEQ) respectively. Only part is a negative externality, because rural agro-aqua systems in Thailand reuse discharges in holding ponds, rice culture, etc. Commercial tilapia and shrimp aquaculture have a value added share of total GDP of 0.......38, and value added of 96.24, resulting in indirect impacts of the industry on the Thai economy of $35 million, and the creation of 16,000 additional jobs. The MCE scenario analysis suggests sustainable expansion is possible for both species. The highly suitable class for tilapia would triple in the dry season...

  10. pyrene on its expression in Nile tilapia

    African Journals Online (AJOL)

    FMV

    2013-11-27

    Nov 27, 2013 ... Full Length Research Paper ... The full-length cDNA was 2107 base pair ... amino acid sequence of Nile tilapia CYP1B1 shows similarities of 79.7, 70.3, 65.7, 65.4, 65.0 ... was determined in liver, intestine and muscle of tilapia.

  11. Production of Genetically Improved Organic Nile Tilapia

    NARCIS (Netherlands)

    Charo, H.; Komen, J.; Bovenhuis, H.; Rezk, M.A.; Ponzoni, R.W.

    2008-01-01

    Demand for organic products for human consumption has been on the increase due to the belief that organic products are safer and healthier to the consumer and the environment. In developing countries, Nile tilapia (Oreochromis niloticus) is usually grown in low-input organically fed ponds with littl

  12. 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.

  13. Echinacea purpurea and Allium sativum as immunostimulants in fish culture using Nile tilapia (Oreochromis niloticus).

    Science.gov (United States)

    Aly, S M; Mohamed, M F

    2010-10-01

    The study was conducted to evaluate the efficiency of echinacea (E) and garlic (G) supplemented diets as immunostimulant for tilapia (Oreochromis niloticus). Seven treatments were designed including a control (C). Fish were fed on 35% protein diet at a rate of 3% body weight per day. Echinacea (1.0 ppt) and garlic (3%) were incorporated in the feed, which was administered for periods of 1, 2 and 3 months (summer season), followed by basal diet for 4 more months (winter season). Neutrophil adherence and haematocrit values increased in both supplemented groups with prolonging period of application. The neutrophils adherence was significantly increased in all treatments except group administered echinacea for 1 month. The lymphocytic counts were significantly (p echinacea for 1 and 2 months when compared with the control and/or other treatments. The gain in the body weight and specific growth rate was significantly increased in all supplemented groups (p 85%) in all the supplemented groups. The percentage of protection, after challenge infection using pathogenic Aeromonas hydrophila was the highest in groups supplemented with echinacea and garlic for 3 months after summer and winter seasons. It could be concluded that echinacea and garlic improve the gain in body weight, survival rate and resistance against challenge infection. Both compounds showed extended effects after withdrawal and improved resistance to cold stress during the winter season. However, a full commercial cost benefit analysis is necessary before recommending their application in aquaculture. © 2010 Blackwell Verlag GmbH.

  14. Heritability of cold tolerance in Nile tilapia, Oreochromis niloticus, juveniles

    NARCIS (Netherlands)

    Charo-Karisa, H.; Rezk, M.A.; Bovenhuis, H.; Komen, J.

    2005-01-01

    The inability of tilapia to tolerate low temperatures is of major economic concern as it reduces their growing season and leads to over winter mortality. In this study, cold tolerance of juvenile Nile tilapia, Oreochromis niloticus, was investigated and heritability estimates obtained. A total of 80

  15. Morphological variation of Nile tilapia populations from major water ...

    African Journals Online (AJOL)

    ACSS

    1Aquaculture Research and Development Center, Kajjansi, Box 530, ... important to establish the existing strains in a manner that is phenotypically discernible where ... morphological variation among the different populations of Nile tilapia and the fish could be grouped ..... Evolutionary history of Nile perch Lates sp. inferred.

  16. Diet supplemented with probiotic for Nile tilapia in polyculture system with marine shrimp.

    Science.gov (United States)

    Jatobá, Adolfo; Vieira, Felipe do Nascimento; Buglione-Neto, Celso Carlos; Mouriño', José Luiz Pedreira; Silva, Bruno Corrêa; Seiftter, Walter Quadros; Andreatta, Edemar Roberto

    2011-12-01

    The aim of this study was to assess the effect of a probiotic (Lactobacillus plantarum) supplemented diet on Nile tilapia (Oreochromis niloticus) in a polyculture system with marine shrimp (Litopenaeus vannamei) as regards culture performance, hematology, and gut bacterial microbiota. Ten 20-m² pens were arranged in one earthen pond and stocked with 2 fish (41.9 g) m(-2) and 10 shrimp (2.3 g) m(-2), in total of 40 Nile tilapias and 200 shrimp per experimental unit. Tilapia groups in five of the experimental units were fed a commercial diet supplemented with L. plantarum and the other five with an unsupplemented commercial diet (control). After 12 weeks of culture, the tilapia groups fed the probiotic-supplemented diet presented values 13.6, 7.5, and 7.1% higher for feed efficiency, yield, and final weight, respectively. Viable culturable heterotrophic bacteria counts were reduced, and the number of lactic acid bacteria was increased in the gut of fish and shrimp fed the probiotic-supplemented diet. Hematological analyses showed higher number of thrombocytes and leukocytes in tilapia fed the supplemented diet. L. plantarum utilized in this study colonized the gut of tilapia and shrimp and resulted in reduced number of total bacteria and increased tilapia final weight and feed efficiency.

  17. Nile tilapia and blue tilapia fry production in a subtropical climate

    Science.gov (United States)

    The relationship between production in earthen ponds located in a subtropical climate of fry suitable for hormonal sex inversion and degree-days was quantified for Nile tilapia (Oreochromis niloticus; Egypt strain) and blue tilapia (O. aureus). Degree-days were calculated for each trial as the sum o...

  18. 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.

  19. 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...

  20. Polyculture of Nile tilapia and shrimp at different stocking densities

    Directory of Open Access Journals (Sweden)

    Ambrosio Paula Bessa Junior

    2012-07-01

    Full Text Available This study aimed to evaluate the productivity, growth performance and economic feasibility of polyculture of Nile tilapia Oreochromis niloticus and shrimp Litopenaeus vannamei at different stocking densities. Feed was provided based on fish requirements. The experiment was conducted at the Aquaculture facility of the Universidade Federal Rural do Semi-Árido - UFERSA, in a completely randomized design with five treatments and four replicates each. Treatments consisted of a tilapia monoculture with 2 tilapias.m-2; and polyculture with 2 tilapias.m-2 and L. vannamei at four different densities (3, 6, 9 and 12 shrimps.m-2. The initial individual biomass for fish and shrimp were 1.23±0.12 g and 0.133±0.009 g, respectively. Water quality parameters, temperature, dissolved oxygen, pH and transparency were monitored. The experiment lasted 120 days and biomass gain was evaluated every two weeks. Final biomass, survival and feed conversion rates were calculated at the end of the experiment. The economic analysis showed that polyculture systems at stocking densities of nine and twelve shrimps.m-2 resulted in higher gross revenue and operational profits of 120.9% and 97.5% respectively, with mean gross return significantly higher than the monoculture. The O. niloticus and L. vannamei polyculture in oligohaline water was shown to be technically and economically feasible. These two species can be cultured together, without competing for the same resources, because they have different trophic niche, thus increasing productivity and economic returns for the farmers.

  1. First records of Ambiphrya and Vorticella spp. (Protozoa, Ciliophora) in cultured Nile tilapia (Oreochromis niloticus) in the central region of Saudi Arabia

    OpenAIRE

    Abdel-Baki, Abdel-Azeem S.; Gewik, Mohamed M.; Al-Quraishy, Saleh

    2014-01-01

    The present study was carried out as part of an ongoing general survey seeking to uncover protozoan parasites infecting cultured tilapia in the central region of Saudi Arabia. In the sample of 400 specimens of tilapia (Oreochromis niloticus) 30 were infested with Ambiphrya ameiuri simultaneously with Vorticella sp. Morphometric criteria were used to describe and identify these species and this study presents the first records of these species among cultured fish in Saudi Arabia.

  2. First records of Ambiphrya and Vorticella spp. (Protozoa, Ciliophora) in cultured Nile tilapia (Oreochromis niloticus) in the central region of Saudi Arabia.

    Science.gov (United States)

    Abdel-Baki, Abdel-Azeem S; Gewik, Mohamed M; Al-Quraishy, Saleh

    2014-12-01

    The present study was carried out as part of an ongoing general survey seeking to uncover protozoan parasites infecting cultured tilapia in the central region of Saudi Arabia. In the sample of 400 specimens of tilapia (Oreochromis niloticus) 30 were infested with Ambiphrya ameiuri simultaneously with Vorticella sp. Morphometric criteria were used to describe and identify these species and this study presents the first records of these species among cultured fish in Saudi Arabia.

  3. Histological Changes of Liver in Overfed Young Nile Tilapia

    NARCIS (Netherlands)

    Taddesse, F.; Huh, M.D.; Bai, S.C.; Vijverberg, J.

    2014-01-01

    We investigated histopathologically liver structural responses of Nile Tilapia Oreochromis niloticus towards overfeeding. Mixed population of O. niloticus with mean weight of 55±3.83 g was acclimated for one week. Then, the fish were separated into control and treatment groups. Glass aquariums with

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

    NARCIS (Netherlands)

    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

  5. Breeding for improved production of Nile tilapia (Oreochromis niloticus L.)

    NARCIS (Netherlands)

    Rutten, M.J.M.

    2005-01-01

    The aim of this thesis was to generate knowledge that supports the design of breeding programs for Nile tilapia targeting genetic improvement of body weight and fillet yield to serve the European market. To this end, both the genetic variation and the performance levels of different strains of tilap

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

    OpenAIRE

    Evans, Joyce J.; Phillip H. Klesius; 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).

  7. 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.

  8. DNA fingerprinting of salinity resistance of full-sib Nile tilapia, Blue ...

    African Journals Online (AJOL)

    ******

    2012-05-01

    May 1, 2012 ... marine and brackish environments for aquaculture become a vital alternative ... Egypt. Fry production. Purebred of each Nile tilapia, O. niloticus and Blue tilapia, O. ..... considers a great potential for the development and.

  9. Does feeding frequency affect utilization of added amino acids in Nile tilapia?

    OpenAIRE

    Hoque, Rezaul; Bajgai, Biswas

    2014-01-01

    Nile tilapia (Oreochromis niloticus) is one of the major farmed fish species, with main production in Asia, South and Central America that can tolerate a wide range of environmental stress and easily adapt with low quality of feed ingredients. The aims of the experiments were to determine effects of feeding frequency on utilization of protein and energy in Nile tilapia, to quantify differences in excretion of ammonia and ammonium in Nile tilapia fed the same daily ration, distributed over 2 a...

  10. 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 ...

  11. Diplostomiasis in cultured and wild tilapia Oreochromis niloticus in Guerrero State, Mexico.

    Science.gov (United States)

    Violante-González, Juan; García-Varela, Martín; Rojas-Herrera, Agustín; Guerrero, Salvador Gil

    2009-09-01

    This paper is a comparative study of Diplostomum (Austrodiplostomum) compactum (Lutz, 1928) in Nile tilapia Oreochromis niloticus (Linneo) from two fish farms and two nearby coastal lagoons in Guerrero state, Mexico. The higher infections levels in cultured tilapia than wild tilapia is attributed to higher fish densities in the culture systems and higher abundance of the snail Biomphalaria cf. havanensis (Pteiffer), first intermediate host of this parasite in freshwater and brackish water systems.

  12. 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.

  13. 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

    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

  14. 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

    2016-08-04

    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.

  15. 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...

  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. 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

  18. 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.

  19. Evaluation of Nile tilapia strains cultivated in cages under different feeding programmes

    Directory of Open Access Journals (Sweden)

    Thiago Archangelo Freato

    2012-06-01

    Full Text Available The objective of this study was to evaluate the performance of three Nile tilapia Oreochromis niloticus strains cultivated in cages and subjected to different feeding programmes. Initially, 31,200 Nile tilapia juveniles with an average weight of 61.15 g were distributed in 48 cages. Two genetically improved strains were used together with one from the Fish Culture Section of Universidade Federal de Lavras (UFLA. The fish were subjected to four feeding programmes, consisting of different levels of crude protein (CP in diets provided at different stages of cultivation. There was no interaction effect of the strain and feeding programme for most variables. The UFLA strain presented the highest weight gain, but with greatest lack of uniformity at the end of cultivation. The feeding programme with diets containing 36%, 32% and 28% CP, consecutively, promoted the highest weight gain and highest final biomass. The UFLA strain has great growth potential, justifying the development of a breeding programme for this strain. Crude protein levels below 36% for tilapias between 60 and 170 g and below 32% for tilapias between 170 and 700 g worsen fish performance.

  20. An optimized group mating design and determination of the admixture rate in Nile tilapia families

    Directory of Open Access Journals (Sweden)

    Yan Zhao

    2016-05-01

    Full Text Available The Nile tilapia is the most productive and internationally traded food fish in the world. Many Nile tilapia families are needed to develop breeding programs for this species. The aim of this study was to develop Nile tilapia families using the Oreochromis species unique breeding characteristics (male territory establisher and female mouth brooders and determine the mixing rate within each family. Both male and female fish were cultured in one pond in the reproductive season and the female mouths were checked every 5–8 days. When embryos were present, they were removed and cultivated independently as a family. As a result, 45 families were developed from the 60 female fish sampled. The embryo survival rate in aerated water varied from 85.5 to 100.0%. Seven polymorphic microsatellite loci were selected from a set of 31 for paternity identification. The CPE (combined paternity exclusion probability of two microsatellite loci was higher than 0.93 and the CPE for the seven loci used in this study was as high as 0.9999. There were no unrelated individuals in five of the seven families analyzed and only one mixed individual in F29 and F30. The overall admixture rate was very low (2.2%. In this study, we developed an optimized group mating system. Furthermore, we verified that for group mating systems there were no mixed individuals in most families and the admixture rate of some families was very low according to the paternity analysis.

  1. First record of three African trichodinids (Ciliophora: Peritrichida) in cultured Nile tilapia (Oreochromis niloticus) in Saudi Arabia with re-evaluation of their host specificity.

    Science.gov (United States)

    Abdel-Baki, Abdel-Azeem Sh; Al Ghamdi, Ali; Al-Quraishy, Saleh

    2017-02-18

    Saudi Arabia has a developing aquaculture industry that farms primarily tilapia. Although trichodinids are presumably the most usually encountered protozoan parasites in these cultured fish, they have rarely been studied in this context, and there is no data on the species that might infect cultured tilapia in Saudi Arabia. The present study was therefore carried out as a general survey to investigate the occurrence and identify the species of trichodinids that can infect cultured tilapia (Oreochromis niloticus) in Saudi Arabia. A total of 500 tilapia fish were collected from fish farms in Riyadh city and examined in order to determine the species of trichodinids present in the positive specimens. Three species of trichodinids (Trichodina maritinkae, T. centrostrigeata and T. frenata) were isolated and described as new records in Saudi Arabia. These trichodinids were found simultaneously in the same fish with overall prevalence of 20% (100/500). The identification and characterization of these three species are documented based on Riyadh specimens, for the first time. Additionally, the present paper confirms the existence of T. frenata for the second time globally and establishes this trichodinid as a new parasite for O. niloticus. T. maritinkae is highly specific to clariids, and previously, it has not been reported from any fish species other than clariids. The present work also confirmed that T. centrostrigeata can also infest cichlid fish. The list of host records of these species is expanded and their host specificity re-evaluated based on the results of this study in addition to the previously published data. We conclude that there is a need for further study of the impacts of these Trichodina spp. on Saudi Arabian fishery sector.

  2. Tilapia culture in Kuwait: constraints and solutions

    OpenAIRE

    Ridha, M.T.

    2006-01-01

    Tilapia farming in Kuwait is in its early stages. Slow growth, high production cost and poor demand are the major constraints to the expansion of tilapia culture in Kuwait. This article presents some suggestions for overcoming these problems to improve the economic feasibility of tilapia culture in Kuwait.

  3. Visual communication stimulates reproduction in Nile tilapia, Oreochromis niloticus (L.).

    Science.gov (United States)

    Castro, A L S; Gonçalves-de-Freitas, E; Volpato, G L; Oliveira, C

    2009-04-01

    Reproductive fish behavior is affected by male-female interactions that stimulate physiological responses such as hormonal release and gonad development. During male-female interactions, visual and chemical communication can modulate fish reproduction. The aim of the present study was to test the effect of visual and chemical male-female interaction on the gonad development and reproductive behavior of the cichlid fish Nile tilapia, Oreochromis niloticus (L.). Fifty-six pairs were studied after being maintained for 5 days under one of the four conditions (N = 14 for each condition): 1) visual contact (V); 2) chemical contact (Ch); 3) chemical and visual contact (Ch+V); 4) no sensory contact (Iso) - males and females isolated. We compared the reproductive behavior (nesting, courtship and spawning) and gonadosomatic index (GSI) of pairs of fish under all four conditions. Visual communication enhanced the frequency of courtship in males (mean +/- SEM; V: 24.79 +/- 3.30, Ch+V: 20.74 +/- 3.09, Ch: 0.1 +/- 0.07, Iso: 4.68 +/- 1.26 events/30 min; P communication did not affect the reproductive behavior of pairs nor did it enhance the effects of visual contact. Therefore, male-female visual communication is an effective cue, which stimulates reproduction among pairs of Nile tilapia.

  4. Agroindustrial byproducts in diets for Nile tilapia juveniles

    Directory of Open Access Journals (Sweden)

    João Sérgio Oliveira Carvalho

    2012-03-01

    Full Text Available This study was conducted to evaluate performance and body composition of tilapia (Oreochromis niloticus fed diets containing byproducts aerial parts of cassava meal (Manihot esculenta, mesquite pod meal (Prosopis juliflora, cocoa meal (Theobroma cacao and palm kernel cake (Elaeis guineensis and to analyze the economic viability of the feed. A total of 1,350 juvenile males (100 g were distributed in 15 cages (1 m³ in completely randomized design with five treatments (basal diet and four test diets and three replicates. The following aspects were evaluated: final weight, total feed intake, total weight gain, feed conversion, specific growth rate, protein efficiency ratio and survival rate, dry matter, crude protein, fat and ash body, the average cost of feed per kilogram of weight gain and economic efficiency rate. No differences were observed for total consumption of food or survival rate. For other variables, the inclusion of cocoa and cassava meal impaired fish performance. No differences were observed for dry matter, crude protein and body ash. The lower body fat accumulation was recorded for the tilapia fed palm kernel cake. The best economic indicators were found to diets containing palm kernel cake. The byproducts evaluated can be used up to 150 g/kg in feed formulation, providing good performance and economic rate for Nile tilapia.

  5. Genetic characterisation of four strains of Nile tilapia (Oreochromie Niloticus L.) using microsatellite markers

    NARCIS (Netherlands)

    Rutten, M.J.M.; Komen, J.; Deerenberg, R.M.; Siwek-Gapinska, M.Z.; Bovenhuis, H.

    2004-01-01

    Four domesticated strains of Nile tilapia (Oreochromis niloticus L.) were genetically characterized using 14 microsatellite markers and 64 animals per strain. Two strains, Chitralada (AIT) and International Development Research Centers (IDRC) were obtained from the AIT institute, Bangkok, Thailand.

  6. 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...

  7. Pituitary control of branchial NCC, NKCC and Na(+), K (+)-ATPase α-subunit gene expression in Nile tilapia, Oreochromis niloticus.

    Science.gov (United States)

    Breves, Jason P; Seale, Andre P; Moorman, Benjamin P; Lerner, Darren T; Moriyama, Shunsuke; Hopkins, Kevin D; Grau, E Gordon

    2014-05-01

    This study investigated endocrine control of branchial ionoregulatory function in Nile tilapia (Oreochromis niloticus) by prolactin (Prl188 and Prl177), growth hormone (Gh) and cortisol. Branchial expression of Na(+)/Cl(-) cotransporter (ncc) and Na(+)/K(+)/2Cl(-) cotransporter (nkcc) genes were employed as specific markers for freshwater- and seawater-type ionocytes, respectively. We further investigated whether Prl, Gh and cortisol direct expression of two Na(+), K(+)-ATPase (nka)-α1 subunit genes, denoted nka-α1a and nka-α1b. Tilapia transferred to fresh water following hypophysectomy failed to adequately activate gill ncc expression; ncc expression was subsequently restored by Prl replacement. Prl188 and Prl177 stimulated ncc expression in cultured gill filaments in a concentration-related manner, suggesting that ncc is regulated by Prl in a gill-autonomous fashion. Tilapia transferred to brackish water (23 ‰) following hypophysectomy exhibited a reduced capacity to up-regulate nka-α1b expression. However, Gh and cortisol failed to affect nka-α1b expression in vivo. Similarly, we found no clear effects of Gh or cortisol on nkcc expression both in vivo and in vitro. When considered with patterns previously described in euryhaline Mozambique tilapia (O. mossambicus), the current study suggests that ncc is a conserved target of Prl in tilapiine cichlids. In addition, we revealed contrasting dependencies upon the pituitary to direct nka-α1b expression in hyperosmotic environments between Nile and Mozambique tilapia.

  8. THE OPTIMAL RATIO OF NILE TILAPIA (Oreochromis niloticus AND COMMON CARP (Cyprinus carpio FOR IMPROVING PRODUCTIVITY ON DEEP WATER POND

    Directory of Open Access Journals (Sweden)

    Imam Taufik

    2013-06-01

    Full Text Available Pond productivity can be increased by applied polyculture system in the deep pond. The purpose of this experiment is to examine the optimal ratio between nile tilapia and common carp, in order to increase the productivity. Nine concrete tanks (15 m2 with water depth of 2.2 m and were completed by water inlet, water outlet, and aeration. Both of nile tilapia and common carp with size ranging of 5-8 cm in total length were used. Stock density was 150 ind./m2. The difference ratio of both fish tilapia and carp of fish stocked as a treatment. The fish ratio this experiment were as followed: A 100%; B 80%:20%; C 60%:40%. Fish fed by pellet until at ad libitum. The duration of experiment was 100 days. Parameters such as survival, growth, and productivity were observed every ten days during the experiment period. Water quality parameters were also periodically observed. The results showed that survival of nile tilapia among the treatments were not significantly different (P>0.05 where survival of common carp at B treatment was better than C treatment (P<0.05. The highest of growth of absolute weight (94.86±2.85 g and total length (14.71±1 cm of nile tilapia at B treatment was found (P<0.05 where the best of growth of absolute weight (106.52±10.47 g and total length (11.57±1.78 cm of common carp was also found at B treatment (P<0.05. Biomass productivity at B treatment was the highest compared with A treatment (P<0.05. Combination between polyculture and the deep water pond technology could increase productivity. The polyculture system and the deep water pond technology would be able to keep constant water quality within in the threshold accordance with the regulation for fish culture.

  9. 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.

  10. 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.

  11. Effects of photoperiod on somatic growth and gonadal development in male nile tilapia

    Directory of Open Access Journals (Sweden)

    Rodrigo Diana Navarro

    2015-10-01

    Full Text Available Rotation and translation of the Earth subject the living organisms to cyclic changes of environmental factors. This study evaluated the effects of photoperiod on growth and gonadal development in Nile tilapia (Oreochromis niloticus. In a completely randomized design experiment, juvenile males were distributed into nine tanks (10 fish per tank and maintained for 60 days under three different light treatments with three repetitions each. The treatments were: T1 - 0 h photoperiod (tanks covered with lids and black plastic; T2 - 12 hours photoperiod (tanks uncovered during photoperiod to provide natural light; and T3 - 24 hours photoperiod (tanks covered with lids equipped with lamps. No significant differences were found between treatments for body length, gonad weight or gonadosomatic index, but body weight was higher in fish subjected to T3 compared with other treatments. Furthermore, significant increases in tubular lumen and germinal epithelium were observed in fish exposed to T1 and T3, respectively. Thus, the manipulation of photoperiod in Nile tilapia culture systems can improve production and consequently increase the economic return on investment.

  12. 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.

  13. Extraction, characterization and application of gelatina obtained from nile tilapia scale, Oreochromis niloticus (Linnaeus, 1758)

    OpenAIRE

    Maria Emanuella de Oliveira Martins

    2015-01-01

    Nile tilapia, Oreochromis niloticus (Linnaeus, 1758), is one of the most cultivated species in our country. The fish processing industries generate large amounts of waste. In the tilapia processing waste materials represent more than 60%. Collagen is the main protein of connective tissue and is the most abundant protein in mammals, birds and fish. A commercial use of the collagen is gelatin, obtained by partial hydrolysis of collagen. Edible coatings and films are types of protection that can...

  14. Transmission and pathology of Streptococcus inane in monosex Nile tilapia (Oreochromis niloticus in aquaculture of Bangladesh

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    Md. Mer Mosharraf Hossain

    2014-04-01

    Full Text Available Streptococcus iniae is a major fish pathogen, recently emergent outbreaks were recorded in commercially cultured monosex Nile tilapia (Oreochromis niloticus result in significant losses termed “streptococcosis”-causes unusual appearances with multi-focal pin-point haemorrhages, abscesses, necrosis and ascites in skin, fin, muscle, liver, spleen, kidney, blood, interstitial fluid specially in central nervous system and brain. This disease was more prevalent (>26% at summer when the water temperature was approximately >25oC, percentage of mortality was higher >41% during the overcrowding and improper water chemistry. Raised levels of glucose and ammonium in blood serum causes reduced number of free blood cells released into the haemolymph to stomach and gut, result in refrain from eating in diseased tilapia. Stocking density (200 fish/decimal; class IV had significant effect (P<0.01 on the total production (5,000 to 5,500 kg/ha. S. iniae in the circulating blood cells, extra-tubular haemal spaces containing blood vessels, fixed phagocytes in the hepatopancreas (gastrointestinal tract, bacteria-like particles in the brain tissue, vacuum and necrosis in hepatocytes revealed with histopathology. In vitro study revealed that cohabitation of dead or infected fish with healthy fish resulted infection (horizontal transmission mechanism to the healthy fish.

  15. Feed intake, growth and metabolism of Nile tilapia (Oreochromis niloticus) in relation to dissolved oxygen concentration

    NARCIS (Netherlands)

    Tran-Duy, A.; Dam, van A.A.; Schrama, J.W.

    2012-01-01

    The objectives of the present study were to determine, for Nile tilapia of different body weights and fed to satiation, (1) the incipient dissolved oxygen (DO) concentration at which feed intake starts to level off and (2) the effect of DO on nitrogen and energy balances. Two successive experiments

  16. 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%),

  17. Water cortisol and testosterone in Nile tilapia (Oreochromis niloticus) recirculating aquaculture systems

    NARCIS (Netherlands)

    Mota, Vasco C.; Martins, Catarina I.M.; Eding, Ep H.; Canário, Adelino V.M.; Verreth, Johan A.J.

    2017-01-01

    The accumulation of steroids released by fish in recirculating aquaculture systems (RAS) may potentially influence their physiology and behavior. The present study examined the release rate of cortisol and testosterone by Nile tilapia, Oreochromis niloticus, and their accumulation in six identical

  18. 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...

  19. Water cortisol and testosterone in Nile tilapia (Oreochromis niloticus) recirculating aquaculture systems

    NARCIS (Netherlands)

    Mota, Vasco C.; Martins, Catarina I.M.; Eding, Ep H.; Canário, Adelino V.M.; Verreth, Johan A.J.

    2017-01-01

    The accumulation of steroids released by fish in recirculating aquaculture systems (RAS) may potentially influence their physiology and behavior. The present study examined the release rate of cortisol and testosterone by Nile tilapia, Oreochromis niloticus, and their accumulation in six identical l

  20. Salinity and diet composition affect digestibility and intestinal morphology in Nile tilapia (Oreochromis niloticus)

    NARCIS (Netherlands)

    Tran, Kim; Schrama, Johan W.; Le, Mai T.T.; Nguyen, Thinh H.; Roem, Arjen J.; Verreth, Johan A.J.

    2017-01-01

    An increase in salinity of the aquatic habitat can be an environmental stress factor for fresh aquatic organism, including fish. The present study investigated the impact of salinity and diet composition on digestibility and intestinal morphology of Nile tilapia. Triplicate groups of 35 fish

  1. 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...

  2. Survival, growth and reproduction of non-native Nile tilapia II: fundamental niche projections and invasion potential in the northern Gulf of Mexico

    Science.gov (United States)

    Lowe, Michael R.; Wu, Wei; Peterson, Mark S.; Brown-Peterson, Nancy J.; Slack, William T.; Schofield, Pamela J.

    2012-01-01

    Understanding the fundamental niche of invasive species facilitates our ability to predict both dispersal patterns and invasion success and therefore provides the basis for better-informed conservation and management policies. Here we focus on Nile tilapia (Oreochromis niloticus Linnaeus, 1758), one of the most widely cultured fish worldwide and a species that has escaped local aquaculture facilities to become established in a coastal-draining river in Mississippi (northern Gulf of Mexico). Using empirical physiological data, logistic regression models were developed to predict the probabilities of Nile tilapia survival, growth, and reproduction at different combinations of temperature (14 and 30°C) and salinity (0–60, by increments of 10). These predictive models were combined with kriged seasonal salinity data derived from multiple long-term data sets to project the species' fundamental niche in Mississippi coastal waters during normal salinity years (averaged across all years) and salinity patterns in extremely wet and dry years (which might emerge more frequently under scenarios of climate change). The derived fundamental niche projections showed that during the summer, Nile tilapia is capable of surviving throughout Mississippi's coastal waters but growth and reproduction were limited to river mouths (or upriver). Overwinter survival was also limited to river mouths. The areas where Nile tilapia could survive, grow, and reproduce increased during extremely wet years (2–368%) and decreased during extremely dry years (86–92%) in the summer with a similar pattern holding for overwinter survival. These results indicate that Nile tilapia is capable of 1) using saline waters to gain access to other watersheds throughout the region and 2) establishing populations in nearshore, low-salinity waters, particularly in the western portion of coastal Mississippi.

  3. Survival, growth and reproduction of non-native Nile tilapia II: fundamental niche projections and invasion potential in the northern Gulf of Mexico.

    Directory of Open Access Journals (Sweden)

    Michael R Lowe

    Full Text Available Understanding the fundamental niche of invasive species facilitates our ability to predict both dispersal patterns and invasion success and therefore provides the basis for better-informed conservation and management policies. Here we focus on Nile tilapia (Oreochromis niloticus Linnaeus, 1758, one of the most widely cultured fish worldwide and a species that has escaped local aquaculture facilities to become established in a coastal-draining river in Mississippi (northern Gulf of Mexico. Using empirical physiological data, logistic regression models were developed to predict the probabilities of Nile tilapia survival, growth, and reproduction at different combinations of temperature (14 and 30°C and salinity (0-60, by increments of 10. These predictive models were combined with kriged seasonal salinity data derived from multiple long-term data sets to project the species' fundamental niche in Mississippi coastal waters during normal salinity years (averaged across all years and salinity patterns in extremely wet and dry years (which might emerge more frequently under scenarios of climate change. The derived fundamental niche projections showed that during the summer, Nile tilapia is capable of surviving throughout Mississippi's coastal waters but growth and reproduction were limited to river mouths (or upriver. Overwinter survival was also limited to river mouths. The areas where Nile tilapia could survive, grow, and reproduce increased during extremely wet years (2-368% and decreased during extremely dry years (86-92% in the summer with a similar pattern holding for overwinter survival. These results indicate that Nile tilapia is capable of 1 using saline waters to gain access to other watersheds throughout the region and 2 establishing populations in nearshore, low-salinity waters, particularly in the western portion of coastal Mississippi.

  4. 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.

  5. 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...

  6. The effects of composting on the nutritional composition of fibrous bio-regenerative life support systems (BLSS) plant waste residues and its impact on the growth of Nile tilapia ( Oreochromis niloticus)

    Science.gov (United States)

    Gonzales, John M.; Lowry, Brett A.; Brown, Paul B.; Beyl, Caula A.; Nyochemberg, Leopold

    2009-04-01

    Utilization of bio-regenerative life support systems (BLSS) plant waste residues as a nutritional source by Nile tilapia ( Oreochromis niloticus) has proven problematic as a result of high concentrations of fibrous compounds in the plant waste residues. Nutritional improvement of plant waste residues by composting with the oyster mushroom ( Pleurotus ostreatus), and the effects on growth and nutrient utilization of Nile tilapia fed such residues were evaluated. Five Nile tilapia (mean weight = 70.9 ± 3.1 g) were stocked in triplicate aquaria and fed one of two experimental diets, cowpea (CP) and composted cowpea (CCP), twice daily for a period of 8 weeks. Composting of cowpea residue resulted in reduced concentrations of nitrogen-free extract, hemi-cellulose and trypsin inhibitor activity, though trypsin inhibitor activity remained high. Composting did not reduce crude fiber, lignin, or cellulose concentrations in the diet. No significant differences ( P ostreatus is not a suitable candidate for culture in conjunction with the culture of Nile tilapia. Additional work is needed to determine what, if any, benefit can be obtained from incorporating composted residue as feed for Nile tilapia.

  7. A high-resolution map of the Nile tilapia genome: a resource for studying cichlids and other percomorphs.

    OpenAIRE

    Guyon Richard; Rakotomanga Michaelle; Azzouzi Naoual; Coutanceau Jean Pierre; Bonillo Celine; D’Cotta Helena; Pepey Elodie; Soler Lucile; Rodier-Goud Marguerite; D’Hont Angelique; Conte Matthew A; van Bers Nikkie EM; Penman David J; Hitte Christophe; Crooijmans Richard PMA

    2012-01-01

    Abstract Background The Nile tilapia (Oreochromis niloticus) is the second most farmed fish species worldwide. It is also an important model for studies of fish physiology, particularly because of its broad tolerance to an array of environments. It is a good model to study evolutionary mechanisms in vertebrates, because of its close relationship to haplochromine cichlids, which have undergone rapid speciation in East Africa. The existing genomic resources for Nile tilapia include a genetic ma...

  8. A high-resolution map of the Nile tilapia genome: a resource for studying cichlids and other percomorphs

    OpenAIRE

    Guyon, Richard; Rakotomanga, Michaelle; Azzouzi, Naoual; Coutanceau, Jean Pierre; Bonillo, Celine; D’Cotta, Helena; Pepey, Elodie; Soler, Lucile; Rodier-Goud, Marguerite; D’Hont, Angelique; Conte, Matthew A; van Bers, Nikkie EM; Penman, David J.; Hitte, Christophe; Crooijmans, Richard Pma

    2012-01-01

    Background The Nile tilapia (Oreochromis niloticus) is the second most farmed fish species worldwide. It is also an important model for studies of fish physiology, particularly because of its broad tolerance to an array of environments. It is a good model to study evolutionary mechanisms in vertebrates, because of its close relationship to haplochromine cichlids, which have undergone rapid speciation in East Africa. The existing genomic resources for Nile tilapia include a genetic map, BAC en...

  9. Optimisation of the pond rearing of Nile tilapia (Oreochromis niloticus L.). The impact of stunting processes and recruitment control

    NARCIS (Netherlands)

    Graaf, de G.J.

    2004-01-01

    Stunting is often considered as a major bottleneck for the pond rearing ofNiletilapia ( Oreochromis niloticus niloticus L.) and was a major topic in this study. Neonteny: the earlier breeding of tilapia in ponds takes place, but

  10. 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.

  11. 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.

  12. Prevalence of Francisella noatunensis subsp. orientalis in cultured tilapia on the island of Oahu, Hawaii.

    Science.gov (United States)

    Soto, Esteban; McGovern-Hopkins, Kathleen; Klinger-Bowen, Ruth; Fox, Bradley K; Brock, James; Antonio, Nathene; Waal, Zelda van der; Rushton, Stephen; Mill, Aileen; Tamaru, Clyde S

    2013-06-01

    Francisellosis is an emergent disease in cultured and wild aquatic animals. The causative agent, Francisella noatunensis subsp. orientalis (Fno), is a gram-negative bacterium recognized as one of the most virulent pathogens of warmwater fish. The main objective of this project was to investigate the prevalence of Fno in cultured tilapia (specifically, Mozambique Tilapia Oreochromis mossambicus, Koilapia [also known as Wami Tilapia] O. hornorum, Blue Tilapia O. aureus, and Nile Tilapia O. niloticus hybrids) on the island of Oahu, Hawaii, using conventional and real-time PCR assays followed by statistical modeling to compare the different diagnostic methods and identify potential risk factors. During 2010 and 2012, 827 fish were collected from different geographical locations throughout the island of Oahu. Upon collection of fish, the water temperature in the rearing system and the length of individual fish were measured. Extraction of DNA from different tissues collected aseptically during necropsy served as a template for molecular diagnosis. High correlation between both molecular methods was observed. Moreover, the bacterium was isolated from infected tilapia on selective media and confirmed to be Fno utilizing a species-specific Taqman-based real-time PCR assay. Although a direct comparison of the prevalence of Fno between the different geographical areas was not possible, the results indicate a high prevalence of Fno DNA in cultured tilapia throughout the farm sites located on Oahu. Of the different tilapia species and hybrids currently cultured in Hawaii, Mozambique Tilapia were more susceptible to infection than Koilapia. Water temperature in the rearing systems and fish size also had a strong effect on the predicted level of infection, with fish held at lower temperatures and smaller fish being more susceptible to piscine francisellosis.

  13. Nutrient retention capabilities of Nile tilapia ( Oreochromis niloticus) fed bio-regenerative life support system (BLSS) waste residues

    Science.gov (United States)

    Gonzales, John M.; Brown, Paul B.

    Nile tilapia were evaluated as a bio-regenerative sub-process for reducing solid waste potentially encountered in bio-regenerative life support systems. Ten juvenile Nile tilapia (mean weight = 2.05 g) were stocked into triplicate aquaria and fed one of seven experimental diets consisting of vegetable, bacterial, or food waste for a period of seven weeks. Weight gain (g), specific growth rate (mg/d), and daily consumption (g) was significantly higher ( p tilapia's ability to utilize these residues as a food source in bio-regenerative support systems.

  14. Confinement during field studies may jeopardize antioxidant and physiological responses of Nile tilapia to contaminants.

    Science.gov (United States)

    Trevisan, Rafael; Uliano-Silva, Marcela; Franco, Jeferson Luis; Posser, Thais; Hoppe, Roberto; Farina, Marcelo; Bainy, Afonso Celso Dias; Dafre, Alcir Luiz

    2013-10-01

    This work evaluates the effects of caging, a known confinement stress, in Nile tilapia (Oreochromis niloticus) during an environmental study in Cubatão river, southern Brazil. Caging animals for 7 days, regardless of being at the reference or at a contaminated site, resulted in lower levels of antioxidant-related defenses (glutathione, glutathione S-transferase, glucose-6-phosphate dehydrogenase) in liver and physiological parameters (blood glucose and lactate) as compared with free-swimming animals. Higher hepatic glutathione reductase activity and elevated Hb content could be associated to contaminant exposure. In conclusion, the confinement stress in caged Nile tilapia biochemical and physiological disturbances, acting as a confounding factor in field studies.

  15. Immunotoxicity and hepatic function evaluation in Nile tilapia (Oreochromis niloticus) exposed to diazinon.

    Science.gov (United States)

    Girón-Pérez, Manuel Iván; Santerre, Anne; Gonzalez-Jaime, Fabiola; Casas-Solis, Josefina; Hernández-Coronado, Marcela; Peregrina-Sandoval, Jorge; Takemura, Akiro; Zaitseva, Galina

    2007-10-01

    The LC(50) of the organophosphorus pesticides (OPs) diazinon to Nile tilapia (Oreochromis niloticus) was determined, thereafter, hepatic activity, phagocytic index, percentages of active cells, relative spleen weight, total IgM concentration and lymphoproliferation rates were compared between diazinon exposed groups (LC(50) and (1/2)LC(50)) and non-exposed control group. Experimental data show that diazinon is highly toxic for juvenile Nile tilapia (LC(50)=7.830 ppm) and presents immunotoxic properties which affect both the innate and cellular adaptive immune responses of this fish, as revealed by the fact that splenocyte proliferation and phagocytic indices were significantly decreased after acute exposure to the pesticide. However, the hepatic biochemical parameters and the total circulating IgM concentrations were not affected in this experimental model.

  16. Essential oil of Lippia alba in the transport of Nile tilapia

    Directory of Open Access Journals (Sweden)

    Janis Cumming Hohlenwerger

    Full Text Available ABSTRACT: This study aimed to examine the action of the essential oil of Lippia alba (EOLA in the stress response for transport of Nile tilapia Oreochromis niloticus . The fish were transported into three treatments (in triplicate: control, 10 and 20 µL L-1 EOLA, with loading density of 15 fish/plastic bags for 8h. Plasma glucose levels were significantly decreased in fish exposed to 20µL L-1 EOLA in comparison with the control group and fish exposed to 10µL L-1 EOLA, but the plasma cortisol, lactate and paraoxonase levels were similar. Un-ionized ammonia and ventilatory rate demonstrated a significant reduction in the treatments with the use of EOLA. In conclusion the use of 20µL L-1 EOLA is indicated for Nile tilapia transport.

  17. Does sex influence intraspecific aggression and dominance in Nile tilapia juveniles?

    Science.gov (United States)

    Pinho-Neto, Cândido Ferreira; Miyai, Caio Akira; Sanches, Fabio Henrique Carretero; Giaquinto, Percília Cardoso; Delicio, Helton Carlos; Barcellos, Leonardo José Gil; Volpato, Gilson Luiz; Barreto, Rodrigo Egydio

    2014-06-01

    Although sex of mature fish is known to influence aggression, this issue has so far been neglected in juveniles. Here, we tested this sex effect and showed that it does not significantly affect intraspecific aggression in juveniles of the cichlid Nile tilapia. To reach this conclusion, we measured the latency period before onset of confrontation, the frequency and types of aggressive interactions, the duration of a dispute, and the probability of becoming dominant. This was done on pairs of Nile tilapia that varied by sex: females×females, males×males, and females×males. In a double blind approach, after pairing, the sex of each individual was histologically verified and contrasted with behavioral data.

  18. 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.

  19. Selection for growth of Nile tilapia (Oreochromis niloticus L.) in low-input environments

    NARCIS (Netherlands)

    Charo-Karisa, H.

    2006-01-01

    Nile tilapia,Oreochromis niloticus,is one of the most important species farmed in the world and is the mainstay of many

  20. Lake Victoria wetlands and the ecology of the Nile tilapia, oreochromis niloticus linn,.

    OpenAIRE

    Balirwa, J.S.

    1998-01-01

    An ecological study of wetlands was undertaken in northern Lake Victoria (East Africa) between 1993 and 1996 with a major aim of characterising shallow vegetation-dominated interface habitats, and evaluating their importance for fish, in particular, for the stocked and socio-economically important Oreochromis niloticus LINNÉ (the Nile tilapia). From field and laboratory experiments, five major habitat types could be defined by the type of the dominant emergent macrophyte at the shore from the...

  1. Comparative time-course study on pituitary and branchial response to salinity challenge in Mozambique tilapia (Oreochromis mossambicus) and Nile tilapia (O. niloticus).

    Science.gov (United States)

    Velan, Ariel; Hulata, Gideon; Ron, Micha; Cnaani, Avner

    2011-12-01

    The physiological response of Mozambique and Nile tilapia transferred from fresh to brackish (15 ppt) water was compared during a one-week time course. Response in the pituitary was measured by the gene expression pattern of prolactin (PRL I), growth hormone (GH), and calcium-sensing receptor (CaSR), while the response in the gills was measured by the gene expression pattern of the prolactin receptor (PRL-R), Na(+)/K(+)/2Cl(-) cotransporter (NKCC) and Na(+)/Cl(-) cotransporter (NCC), and by activity and expression of Na(+)/K(+)-ATPase (NKA). The time-course curves of plasma osmolality levels indicate a rapid elevation 24 h after transfer, which later decreased and maintained at stable level. PRL I expression decreased in both species, but with stronger response in the Nile tilapia, while no differences were found in the slightly elevated levels of GH mRNA. The branchial response demonstrated a faster up-regulation of NKA and NKCC in the Mozambique tilapia, but similar levels after a week, while Nile tilapia had stronger and constant down-regulation of NCC. The time-course response of the measured osmoregulatory parameters indicate that 24 h after transfer is a critical time point for brackish-water adaptation. The differences in responses to saltwater challenge between Mozambique and Nile tilapia shown in this study may be associated with the differences in saltwater tolerance between these two tilapiine species.

  2. Ectoparasites of Nile tilapia (Oreochromis niloticus in cage farming in a hydroelectric reservoir in Brazil

    Directory of Open Access Journals (Sweden)

    Aline Cristina Zago

    Full Text Available For this study, we performed a parasitological analysis of cage-cultured Nile tilapia (Oreochromis niloticus from the Água Vermelha Reservoir, Southeastern Brazil, and verified relationships with limnological data, seasonality, and fish growth phase. From March 2010 to March 2011, sixty-three specimens of O. niloticusin three growth phases (i.e., initial, intermediate, and final were collected. All fish specimens were infested with at least one ectoparasite species (prevalence = 100%. Five species of protozoans (Trichodina compacta, Trichodina magna, Ichthyophthirius multifiliis,Piscinoodinium pillulare, and Epistylissp. and five species of monogenoids (Cichlidogyrus halli, Cichlidogyrus thurstonae,Cichlidogyrus sp. 1, Scutogyrus longicornis, and Gyrodactylus sp. were observed. The abundance of Trichodina spp. and the prevalence of Epistylis sp. were higher in the dry season, and the prevalence of C. halli was higher in the rainy season. For the majority of ectoparasites found in this study, fish in the intermediate and final phases had higher parasitism rates than those in the initial phase. The data presented may help fish farmers to understand the parasite dynamics of the fish species studied in cage-farming systems.

  3. Chemical compositions and muddy flavour/odour of protein hydrolysate from Nile tilapia and broadhead catfish mince and protein isolate.

    Science.gov (United States)

    Yarnpakdee, Suthasinee; Benjakul, Soottawat; Penjamras, Pimpimol; Kristinsson, Hordur G

    2014-01-01

    Chemical compositions and muddy compounds in dorsal and ventral muscles of Nile tilapia and broadhead catfish were comparatively studied. On a dry weight basis, Nile tilapia was rich in protein (93.1-93.8%), whilst broadhead catfish contained protein (55.2-59.5%) and lipid (36.6-42.4%) as the major constituents. Ventral portion had higher lipid or phospholipid contents with coincidentally higher geosmin and/or 2-methylisoborneol (2-MIB) contents. Geosmin was found in mince of Nile tilapia and broadhead catfish at levels of 1.5 and 3.2μg/kg, respectively. Broadhead catfish mince had 2-MIB at level of 0.8μg/kg, but no 2-MIB was detected in Nile tilapia counterpart. When pre-washing and alkaline solubilisation were applied for preparing protein isolate (PI), lipid and phospholipid contents were lowered with concomitant decrease in geosmin and 2-MIB contents. Protein hydrolysate produced from PI had a lighter colour and a lower amount of muddy compounds, compared with that prepared from mince. Therefore, PI from both Nile tilapia and broadhead catfish could serve as the promising proteinaceous material, yielding protein hydrolysate with the negligible muddy odour and flavour.

  4. Quantification of intestinal bacteria, operating cost and performance of fingerlings Nile tilapia subjected to probiotics

    Directory of Open Access Journals (Sweden)

    Nilton Garcia-Marengoni

    2015-05-01

    Full Text Available The use of microorganisms of the genus Bacillus in aquaculture is a nutritional management practice that is rapidly expanding in regions with intensive fish farming. This study aimed to quantify the total bacteria and total coliforms from the intestinal microbiota and estimate the partial operating costs and growth performance of Nile tilapia (Oreochromis niloticus of the GIFT strain. A total of 1,200 post-larvae (24.7 ± 0.50 mg were distributed into 24 aquaria (0.03-m³ capacity within a completely randomized design in 2 x 3 factorial (phase x bacteria, with four replications. Each aquarium, containing 50 post-larvae (sex reversal phase or 30 fish (fingerlings phase, it was considered to be an experimental unit, consisting of three treatments (diet+Bacillus subtilis C-3102, diet+Bacillus cereus var. toyoi and diet without probiotic addition. The quantification of the total bacteria and total coliforms of the intestinal microbiota of tilapia were influenced (P 0.05 by adding probiotics in the diets and no effect of the interaction between phase and bacteria was observed. The weight gain, average daily weight gain, specific growth rate and apparent feed conversion were not affected (P > 0.05 by inclusion of probiotics as part of the diets. The inclusion of B. subtilis and B. cereus as part of diets for Nile tilapia promotes intestinal colonization and improves the survival rate without negatively influencing the feed intake, total biomass, gross revenue and partial operating costs and net revenue. Therefore it recommends the use of these probiotics to growth of tilapia fingerlings Nile, GIFT strain.

  5. Effects of Dietary Exposure to Sulfamethazine on the Hematological Parameters and Hepatic Oxidative Stress Biomarkers in Nile Tilapia (Oreochromis niloticus).

    Science.gov (United States)

    Sampaio, Fernanda Garcia; Carra, Maria Lídia; Jonsson, Claudio Martin; Gonçalves, Vitoria Teodoro; Dal'Bo, Genoefa; Nunes, Kátia Santos Damacena; Valim, José Henrique; Dallago, Bruno Stéfano Lima; do Nascimento de Queiroz, Sonia Claudia; Reyes, Felix Guillermo Reyes

    2016-10-01

    Sulfamethazine (SMZ) is one of the most commonly used sulfonamide compounds in fish farming, and its physiological effects on fish are unknown. SMZ was administered to juvenile Nile tilapia (Oreochromis niloticus) at a dose level of 422 mg kg(-1) body weight, for a period of 11 days, via medicated feed. Fish were divided into two groups, the control group (CG) and the group fed with SMZ in feed. The administration of SMZ did not alter the erythrograms and leukograms of the Nile tilapia. The SMZ-fed group showed the same hepatic lipid peroxidation (LPO) concentration as the CG. Nonetheless, the oral administration of SMZ raised the hepatic catalase (CAT) and glutathione S-transferase (GST) activities, the increase probably being sufficient to prevent hepatic LPO production. The oral administration of SMZ affects the hepatic GST and CAT activities of Nile tilapia.

  6. Gill monogeneans of Nile tilapia (Oreochromis niloticus) and red hybrid tilapia (Oreochromis spp.) from the wild and fish farms in Perak, Malaysia: infection dynamics and spatial distribution.

    Science.gov (United States)

    Lim, Shen-Yin; Ooi, Ai-Lin; Wong, Wey-Lim

    2016-01-01

    Tilapia is one of the commercially important fish in Malaysia as well as in other parts of the world. An understanding of monogenean infection dynamics in tilapia fish may assist us in searching for some intervention measures in reducing the loss of fish caused by parasitic diseases. The present study aimed (1) to compare infection level of monogeneans between the wild and cultured Oreochromis niloticus, and between the cultured O. niloticus and cultured red hybrid tilapia, and (2) to examine the spatial distribution of monogenean species over the gills of the different host species. From a total of 75 fish specimens, six species of monogeneans from two genera: Cichlidogyrus (C. halli, C. mbirizei, C. sclerosus, C. thurstonae, C. tilapiae) and Scutogyrus (S. longicornis) were identified. Data showed that the infection level of cultured O. niloticus was higher than that of the wild O. niloticus, however, the former was lower than that of the cultured red hybrid tilapia. Higher species richness of monogeneans was observed in the cultured red hybrid tilapia as compared to the others. Results for spatial distribution showed that the monogeneans have no preference on the left or right sides of the gills. However, C. halli, C. mbirizei, and C. tilapiae showed preferences on specific gill arches in the cultured O. niloticus and red hybrid tilapia. In general, the gill arch IV harboured the least number of monogeneans. The susceptibility of monogenean infection between the different types of tilapia is discussed.

  7. Efficiency of eugenol as anesthetic for the early life stages of Nile tilapia (Oreochromis niloticus

    Directory of Open Access Journals (Sweden)

    Paula A.P. Ribeiro

    2015-03-01

    Full Text Available In aquaculture, activities with anesthetic compounds are usually used in order to ensure the welfare of farmed fish, allowing handling out of water with decreased trauma by stress. Presently, there is no information about anesthetic action of eugenol in early life stages of Nile tilapia (Oreochromis niloticus. The objective of this study was to evaluate different concentrations of eugenol for larvae and juveniles of Nile tilapia. Sixty animals were used for each group of weight, group I = 0.02 g; group II = 0.08 g; group III = 0.22 g; group IV = 2.62 g; and group V = 11.64 g. The eugenol concentrations tested were 50, 75, 100, 125, 150 and 175 mg L-1. No mortality was reported during the tests with eugenol. Tilapia larvae with 0.02 g and juveniles around 11.64 g can be anesthetized with eugenol concentrations between 150 and 175 mg L-1, since they determine the shortest sedation time (23 and 72 seconds, for the group of lowest and highest weights, respectively.

  8. Efficiency of eugenol as anesthetic for the early life stages of Nile tilapia (Oreochromis niloticus).

    Science.gov (United States)

    Ribeiro, Paula A P; Miranda-Filho, Kleber C; Melo, Daniela C de; Luz, Ronald K

    2015-03-01

    In aquaculture, activities with anesthetic compounds are usually used in order to ensure the welfare of farmed fish, allowing handling out of water with decreased trauma by stress. Presently, there is no information about anesthetic action of eugenol in early life stages of Nile tilapia (Oreochromis niloticus). The objective of this study was to evaluate different concentrations of eugenol for larvae and juveniles of Nile tilapia. Sixty animals were used for each group of weight, group I = 0.02 g; group II = 0.08 g; group III = 0.22 g; group IV = 2.62 g; and group V = 11.64 g. The eugenol concentrations tested were 50, 75, 100, 125, 150 and 175 mg L-1. No mortality was reported during the tests with eugenol. Tilapia larvae with 0.02 g and juveniles around 11.64 g can be anesthetized with eugenol concentrations between 150 and 175 mg L-1, since they determine the shortest sedation time (23 and 72 seconds, for the group of lowest and highest weights, respectively).

  9. Multiplex PCR for simultaneous detection of Streptococcus agalactiae, Streptococcus iniae and Lactococcus garvieae: a case of S. agalactiae infection in cultured Nile tilapia (Oreochromis niloticus) and red tilapia (Oreochromis niloticus x Oreochromis mossambicus)

    OpenAIRE

    Chutima Tantikitti; Naraid Suanyuk; Akkarawit Itsaro

    2012-01-01

    A multiplex PCR (m-PCR) technique was developed for simultaneous detection of the causative agents responsible forstreptococcosis of cultured fish in Thailand i.e., Streptococcus agalactiae, Streptococcus iniae, and Lactococcus garvieae.The study on the sensitivity of the technique indicated that the minimum detected DNA concentration was 9.76, 39.06, and19.53 pg for S. agalactiae, S. iniae and L. garvieae, respectively. Detection of streptococcosis in healthy and diseased Niletilapia (Oreoch...

  10. 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.

  11. Growth comparison of Nile tilapia (Oreochromis niloticus) and Blue ...

    African Journals Online (AJOL)

    Administrator

    2011-09-26

    Sep 26, 2011 ... the effect of interspecific hybridization and genetically modified breeding by introducing a fragmented .... de-chlorinated water and adequate aeration system, cleaned once daily by .... characteristics of both species, being more cold tolerant .... breeding: production of highly immune genetically modified Nile.

  12. Effects of socking [sic] density on ammonia excretion and the growth of Nile tilapia (Oreochromis niloticus L.)

    OpenAIRE

    Ali, M.S.; Stead, S. M.; Houlihan, D F

    2006-01-01

    The effects of stocking density (10, 15, 50 & 75 fish in 65L tank) and ammonia excretion on the growth of Nile tilapia, Oreochromis niloticus (12.19 ± 1.21 g) were investigated. Increasing stocking density of Nile tilapia from 15 fish/tank (2.81 g fish/L) to 75 fish/tank (14.07 g fish/L) resulted in associated increase in ammonia level (1.48 ± 0.87 mg/L to 26.44 ± 11.4 mg/L) and significantly lower growth rates. Significantly better feed conversion ratios were found for fish reared at lower (...

  13. Hydroyeast Aquaculture® as a reproductive enhancer agent for the adult Nile tilapia (Oreochromis niloticus Linnaeus, 1758).

    Science.gov (United States)

    Mehrim, Ahmed I; Khalil, Fathy F; Hassan, Montaha E

    2015-04-01

    Tilapias are becoming increasingly popular culture fish because of their superior culture adaptability. In recent years, there has been a great interest in the use of probiotics in fish aquaculture. The objectives of the present study were to evaluate the effect of dietary graded levels (0, 5, 10, and 15 g/kg commercial diet, referred to treatments numbers T1, T2, T3, and T4, for males and T5, T6, T7, and T8 treatments for females) of a new probiotic Hydroyeast Aquaculture(®) on hematological and biochemical parameters, serum sex hormones, and the reproductive efficiency parameters of the adult Nile tilapia Oreochromis niloticus for 8 weeks. Results revealed that high levels of probiotics diet, 15 g (T4, ♂) and 10 g (T7, ♀) probiotic/kg diet, significantly (P ≤ 0.05) enhanced the physiological responses (hematological as well as serum biochemical parameters) together with, reproductive performances (sex hormones, testes and sperm quality parameters, absolute and relative fecundity, and ovarian measurements). Therefore, it could be conclude that Hydroyeast Aquaculture(®) is useful at levels of 15 g (T4) and 10 g (T7)/kg diet in improving the reproductive efficiency of adult O. niloticus males and females, respectively. Thus, the use of Hydroyeast Aquaculture(®) may be economically important for fish hatcheries.

  14. Hematology and productive performance of nile tilapia (Oreochromis niloticus naturally infected with Flavobacterium columnare

    Directory of Open Access Journals (Sweden)

    F. A Sebastião

    2011-03-01

    Full Text Available Columnaris disease is one of the main causes of mortality in tilapia rearing and is responsible for large economic losses worldwide. Hematology is a tool that makes it possible to study organisms' physiological responses to pathogens. It may assist in making diagnoses and prognoses on diseases in fish populations. The hematological variables of nile tilapia were studied in specimens with a clinical diagnosis of columnaris disease and in specimens that were disease-free. The total erythrocyte count, hemoglobin rate, hematocrit percentage, mean corpuscular hemoglobin (MCH, mean corpuscular hemoglobin concentration (MCHC, mean corpuscular volume (MCV, organic defense blood cell percentages (leukocytes and thrombocytes and hepatosomatic and splenosomatic index were determined. The results showed that there were changes in the erythrocytic series and in organic defense blood cells, in the fish infected with the bacterium, with reductions in erythrocytic variables and significant increases in the numbers of circulating lymphocytes and neutrophils.

  15. Global DNA Methylation Changes in Nile Tilapia Gonads during High Temperature-Induced Masculinization

    Science.gov (United States)

    Wang, Hui; Li, Ning

    2016-01-01

    In some fish species, high or low temperature can switch the sex determination mechanisms and induce fish sex reversal when the gonads are undifferentiated. During this high or low temperature-induced sex reversal, the expressions of many genes are altered. However, genome-wide DNA methylation changes in fish gonads after high or low temperature treatment are unclear. Herein, we compared the global DNA methylation changes in the gonads from control females (CF), control males (CM), high temperature-treated females (TF), and high temperature-induced males (IM) from the F8 family of Nile tilapia (Oreochromis niloticus) using methylated DNA immunoprecipitation sequencing. The DNA methylation level in CF was higher than that in CM for various chromosomes. Both females and males showed an increase in methylation levels on various chromosomes after high-temperature induction. We identified 64,438 (CF/CM), 63,437 (TF/IM), 98,675 (TF/CF), 235,270 (IM/CM) and 119,958 (IM/CF) differentially methylated regions (DMRs) in Nile tilapia gonads, representing approximately 0.70% (CF/CM), 0.69% (TF/IM), 1.07% (TF/CF), 2.56% (IM/CM), and 1.30% (IM/CF)of the length of the genome. A total of 89 and 65 genes that exhibited DMRs in their gene bodies and promoters were mapped to the Nile tilapia genome. Furthermore, more than half of the genes with DMRs in the gene body in CF/CM were also included in the IM/CM, TF/CF, TF/IM, and IM/CF groups. Additionally, many important pathways, including neuroactive ligand-receptor interaction, extracellular matrix-receptor interaction, and biosynthesis of unsaturated fatty acids were identified. This study provided an important foundation to investigate the molecular mechanism of high temperature-induced sex reversal in fish species. PMID:27486872

  16. Effects of dietary genistein on GH/IGF-I axis of Nile tilapia Oreochromis niloticus

    Science.gov (United States)

    Chen, Dong; Wang, Wei; Ru, Shaoguo

    2016-09-01

    There is considerable concern that isoflavones, such as genistein in fish feed composed of soybean protein, aff ects somatic growth in fish. Our previous works demonstrated that 30 and 300 μg/g dietary genistein had no significant eff ect on growth performance in Nile tilapia ( Oreochromis niloticus), but the higher level of genistein (3 000 μg/g) significantly depressed growth. This study was conducted to further examine the eff ects of dietary genistein on the endocrine disruption on growth hormone/insulin-like growth factor-I (GH/IGF-I) axis in Nile tilapia ( O. niloticus). Juvenile fish were fed by hand twice daily to satiation with one of four isonitrogenous and isoenergetic diets, each containing either 0, 30, 300 or 3 000 μg/g genistein. Following an 8-week feeding period, plasma GH and IGF-I levels were investigated by radioimmunoassay and gene expression levels of gh, ghrelin, gnrhs, ghr, npy, npyrs, pacap, ghrs, i gf-I, igf-Ir, and igfbp3 were examined by real-time PCR. The results show that no significant change in plasma GH and IGF-I levels in fish fed with diets containing 30 μg/g and 300 μg/g genistein. mRNA expression of genes along the GH/IGF-I axis remained unaff ected, except for igf-Ir, which was stimulated by the 300 μg/g genistein diet. While in fish fed the 3 000 μg/g genistein diet, the plasma GH and IGF-I levels decreased, and mRNA expression of gh, ghr2, npyr1, igf-I, and igf-Ir were also significantly depressed. In contrast, npy and igfbp3 mRNA expression were enhanced. This study provides convincing evidence for growth impediment by genistein by disturbing the GH/IGF-I axis in Nile tilapia O. niloticus.

  17. Identification and expression profiles of multiple genes in Nile tilapia in response to bacterial infections.

    Science.gov (United States)

    Pridgeon, Julia W; Aksoy, Mediha; Klesius, Phillip H; Li, Yuehong; Mu, Xingjiang; Srivastava, Kunwar; Reddy, Gopal

    2011-11-15

    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 hydrophila. A total of 31 unique expressed sequence tags (ESTs) were identified from 192 clones of the subtractive cDNA library. Quantitative PCR revealed that nine of the 31 ESTs were significantly (ptilapia at 6h post infection with A. hydrophila at an injection dose of 10(5)CFU per fish (≈ 20% mortality). Of the nine upregulated genes, four were also significantly (ptilapia at 6h post infection with A. hydrophila at an injection dose of 10(6)CFU per fish (≈ 60% mortality). Of the four genes induced by A. hydrophila at both injection doses, three were also significantly (ptilapia at 6h post infection with Streptococcus iniae at doses of 10(6) and at 10(5)CFU per fish (≈ 70% and ≈ 30% mortality, respectively). The three genes induced by both bacteria included EST 2A05 (similar to adenylate kinase domain containing protein 1), EST 2G11 (unknown protein, shared similarity with Salmo salar IgH locus B genomic sequence with e value of 0.02), and EST 2H04 (unknown protein). Significant upregulation of these genes in Nile tilapia following bacterial infections suggested that they might play important roles in host response to infections of A. hydrophila and S. iniae.

  18. A high-resolution map of the Nile tilapia genome: a resource for studying cichlids and other percomorphs.

    OpenAIRE

    Guyon, Richard; Rakotomanga, Michaëlle; Azzouzi, Naoual; Coutanceau, Jean-Pierre; Bonillo, Celine; D'Cotta, Helena; Pepey, Elodie; Soler, Lucile; Rodier-Goud, Marguerite; D'Hont, Angélique; Conte, Matthew,; Van Bers, Nikkie; Penman, David,; Hitte, Christophe; Crooijmans, Richard

    2012-01-01

    International audience; ABSTRACT: BACKGROUND: The Nile tilapia (Oreochromis niloticus) is the second most farmed fish species worldwide. Itis also an important model for studies of fish physiology, particularly because of its broadtolerance to an array of environments. It is a good model to study evolutionary mechanismsin vertebrates, because of its close relationship to haplochromine cichlids, which haveundergone rapid speciation in East Africa. The existing genomic resources for Nile tilapi...

  19. A high-resolution map of the Nile tilapia genome: a resource for studying cichlids and other percomorphs

    OpenAIRE

    Guyon, Richard; Rakotomanga, Michaëlle; Azzouzi, Naoual; Coutanceau, Jean-Pierre; Bonillo, Celine; D'Cotta, Helena; Pepey, Elodie; Soler, Lucile; Rodier-Goud, Marguerite; D'Hont, Angélique; Conte, Matthew,; Van Bers, Nikkie; Penman, David,; Hitte, Christophe; Crooijmans, Richard P M A

    2012-01-01

    BACKGROUND: The Nile tilapia (Oreochromis niloticus) is the second most farmed fish species worldwide. Itis also an important model for studies of fish physiology, particularly because of its broadtolerance to an array of environments. It is a good model to study evolutionary mechanismsin vertebrates, because of its close relationship to haplochromine cichlids, which haveundergone rapid speciation in East Africa. The existing genomic resources for Nile tilapiainclude a genetic map, BAC end se...

  20. Small crumbled diet versus powdered diet in restricted feeding management of juvenile Nile tilapia

    OpenAIRE

    Oliveira-Segundo,José Nacélio; Lima,Francisco Roberto dos Santos; Akao,Michael Masaki Freitas; Marcelo Vinícius do Carmo e Sá

    2013-01-01

    The pellet size of the diet can affect both fish growth performance and the water quality of the rearing units. The present work assessed the effects of feeding juvenile Nile tilapia, Oreochromis niloticus (L.) a small crumbled diet (SCD; 0.8 mm) on water quality and growth performance. Fish were reared for six weeks in twenty 250-L polyethylene outdoor tanks at a density of 10 juveniles tank-1 (40 fish m-3). There were two feeding rates (standard and restricted) and two types of artificial f...

  1. Mianserin affects alarm reaction to conspecific chemical alarm cues in Nile tilapia.

    Science.gov (United States)

    Barreto, Rodrigo Egydio

    2017-02-01

    In this study, I show that mianserin, a chemical with serotonin and adrenoceptor antagonist activities, increases fish vulnerability to a potential predator threat, when prey fish must deal with this threat based on conspecific chemical alarm cues. For that, I evaluated whether mianserin, diluted in the water, influences the behavioral responses of Nile tilapia (Oreochromis niloticus) to conspecific skin extract (chemical alarm cues). I found that, while mianserin did not abolished antipredator responses, this drug mitigates some components of this defensive reaction. Thus, a potential decrease in serotonin and adrenergic activities reduces the ability of dealing with predators when perceiving conspecific chemical alarm cues.

  2. Sublethal ammonia exposure of Nile tilapia (Oreochromis niloticus L.): effects on gill, liver and kidney histology.

    Science.gov (United States)

    Benli, Aysel Cağlan Karasu; Köksal, Gülten; Ozkul, Ayhan

    2008-07-01

    The effects of exposures to sublethal ammonia concentrations on Nile tilapia (Oreochromis niloticus L.) were determined with respect to histology. The experiments were conducted for six weeks and with four different ammonia concentrations (control, 1, 2, 5, 10 mg l(-1) TA-N). Fish exposed to different ammonia concentrations displayed histopathologic alterations in the gills, liver and kidney. Gill tissues displayed hyperemia, chloride cell proliferation, fusion in secondary lamella, telangiectasis. Liver tissue revealed cloudy swelling and hydropic degeneration, whereas in kidney tissues hyperemia and glomerulonephritis were observed.

  3. Preliminary Studies on Bioconcentration of Heavy Metals in Nile Tilapia from Tono Irrigation Facility

    Directory of Open Access Journals (Sweden)

    Apori Ntiforo Sam-Quarcoo Dotse

    2012-12-01

    Full Text Available The present study has identified and measured the concentrations of heavy metals in the body tissue of Nile Tilapia from the Tono Irrigation facility located in the Kassena-Nankana East District of the Upper East Region of Ghana. Using Neutron Activation Analysis (NAA, Arsenic, Cadmium, Chromium, Copper, Iron, Manganese, Nickel, Vanadium and Zinc were identified and their mean concentrations were 0.23, 0.02, 0.2, 1.03, 45.95, 19, 0.21, 0.27 and 12.76 :g/g, respectively. The order of mean concentration of heavy metals in fish samples was Cd

  4. Does selection in a challenging environment produce Nile tilapia genotypes that can thrive in a range of production systems?

    Science.gov (United States)

    Thoa, Ngo Phu; Ninh, Nguyen Huu; Knibb, Wayne; Nguyen, Nguyen Hong

    2016-02-19

    This study assessed whether selection for high growth in a challenging environment of medium salinity produces tilapia genotypes that perform well across different production environments. We estimated the genetic correlations between trait expressions in saline and freshwater using a strain of Nile tilapia selected for fast growth under salinity water of 15-20 ppt. We also estimated the heritability and genetic correlations for new traits of commercial importance (sexual maturity, feed conversion ratio, deformity and gill condition) in a full pedigree comprising 36,145 fish. The genetic correlations for the novel characters between the two environments were 0.78-0.99, suggesting that the effect of genotype by environment interaction was not biologically important. Across the environments, the heritability for body weight was moderate to high (0.32-0.62), indicating that this population will continue responding to future selection. The estimates of heritability for sexual maturity and survival were low but significant. The additive genetic components also exist for FCR, gill condition and deformity. Genetic correlations of harvest body weight with sexual maturity were positive and those between harvest body weight with FCR were negative. Our results indicate that the genetic line selected under a moderate saline water environment can be cultured successfully in freshwater systems.

  5. Monogenoidea (Dactylogyridae em tilápias-do-nilo cultivadas sob diferentes densidades de estocagem em tanques-rede Monogenoidea (Dactylogyridae in Nile tilapia cultured under different stocking densities in cages

    Directory of Open Access Journals (Sweden)

    N.G. Marengoni

    2009-04-01

    Full Text Available Avaliaram-se a prevalência e a intensidade de infecção por Monogenoidea em tilápias-do-nilo (Oreochromis niloticus cultivadas sob diferentes densidades de estocagem em tanques-rede de 4m³. O delineamento experimental foi inteiramente ao acaso, com quatro tratamentos - densidades (D de D1=250, D2=300, D3=350 e D4=400 peixes/m³, três repetições por tratamento, utilizando-se 360 peixes capturados e analisados no período de fevereiro a junho de 2003. Os parâmetros físico-químicos da água foram mensalmente monitorados. Observaram-se prevalências de 52,8; 62,5; 69,4; 83,3; 58,3% e intensidade média parasitária de 112,8; 65,7; 274,0; 97,8; 100,2 de Dactylogyrus sp. (Monogenoidea: Dactylogyridae. Não houve relação da prevalência e intensidade de infecção com a densidade de cultivo, porém foi verificado efeito quadrático (PThe prevalence and infection intensity of Monogenoidea in Nile tilapia (Oreochromis niloticus cultivated under different stocking densities in 4m³ cages were evaluated. The experiment was designed in sample random sampling with four treatments - densities (D of D1=250, D2=300, D3=350, and D4=400 fish/m³- and three repetitions, using 360 fish captured and analyzed during the period from February to June 2003. Physiochemical parameters of the water were monthly monitored. Prevalences of 52.8; 62.5; 69.4; 83.3; and 58.3% and parasitic mean intensities of 112.8; 65.7; 274.0; 97.8; and 100.2 Dactylogyrus sp. (Monogenoidea: Dactylogyridae were observed. No relationship between the prevalence and infection intensity with the cultivation density was found. However, quadratic effect was verified (P<0.05 related to the parasitic intensity in function of the month. High mean intensity of infection (274 and high prevalence (83.3% were verified in the months in that the temperature and the transparency of the water oscillated below the recommended limits for the thermal comfort and well-being of tilapia.

  6. Genetic and environmental factors affecting growth of Nile tilapia (Oreochromis niloticus) juveniles: modelling spatial correlations between hapas

    NARCIS (Netherlands)

    Charo-Karisa, H.; Komen, J.; Rezk, M.A.; Reynolds, S.; Ponzoni, R.W.; Bovenhuis, H.

    2006-01-01

    The aim of this study was to quantify the environmental and genetic effects on early growth of Nile tilapia, Oreochromis niloticus, in hapa-in-earthen pond systems. In a pilot study, we grew swim-up fry with or without supplementary feed in hapas suspended in fertilized ponds at 5, 10, 15, and 20 fr

  7. Heritability estimates and response to selection for growth of Nile tilapia (Oreochromis niloticus ) in low-input earthen ponds

    NARCIS (Netherlands)

    Charo-Karisa, H.; Komen, J.; Rezk, M.A.; Ponzoni, R.W.; Arendonk, van J.A.M.; Bovenhuis, H.

    2006-01-01

    This study presents results of two generations of selection (G1 and G2) for growth of Nile tilapia. The selection environment consisted of earthen ponds which were fertilized daily with 50 kg dry matter (dm)/ha chicken manure. No supplementary feeds were provided. In total, 6429 fully pedigreed expe

  8. Effects of dietary starch and energy levels on maximum feed intake, growth and metabolism of Nile tilapia, Oreochromis niloticus

    NARCIS (Netherlands)

    Tran Duy, A.; Smit, B.; Dam, van A.A.; Schrama, J.W.

    2008-01-01

    The aim of this study was to gain insight into how Nile tilapia (Oreochromis niloticus) regulate feed and energy intake in response to diets low and high in starch and cellulose. It was hypothesized that high-starch diets would reduce feed intake due to the effect of high blood glucose level, and th

  9. Genotype by environment interaction for harvest weight, growth rate and shape between monosex and mixed sex Nile tilapia (Oreochromis niloticus)

    NARCIS (Netherlands)

    Omasaki, S.K.; Charo-Karisa, H.; Kahi, A.K.; Komen, H.

    2016-01-01

    In Kenya, Nile tilapia (Oreochromis niloticus) is mostly grown in ponds. To avoid excessive reproduction and stunted growth, fingerlings are treated with methyl-testosterone to make all-male populations (monosex). For a national breeding programme that aims to provide genetically improved broodst

  10. 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...

  11. Genetic parameters for reproductive traits in female Nile tilapia (Oreochromis niloticus): I. Spawning success and time to spawn

    NARCIS (Netherlands)

    Trong, T.Q.; Arendonk, van J.A.M.; Komen, J.

    2013-01-01

    Breeding programmes for Nile tilapia typically use nested mating designs with 2 females mated to 1 male to produce paternal half-sib families. This mating design can take up to 3 months or longer to produce the desired number of half-sib family groups. Prolonged family production increases common en

  12. Interaction between dissolved oxygen concentration and diet composition on growth, digestibility and intestinal health of Nile tilapia (Oreochromis niloticus)

    NARCIS (Netherlands)

    Tran, N.T.K.; Dinh, Ngu T.; Tin, Nguyen Hong; Roem, A.J.; Schrama, J.W.; Verreth, J.A.J.

    2016-01-01

    The present study was undertaken to evaluate the individual and combined effects of oxygen concentration and
    diet composition on the growth, nutrient utilization and intestinal morphology of Nile tilapia (Oreochromis
    niloticus). Two recirculating aquaculture systems were used to create the

  13. A high-resolution map of the Nile tilapia genome: a resource for studying cichlids and other percomorphs

    NARCIS (Netherlands)

    Guyon, R.; Rakotomanga, M.; Azzouzi, N.; Coutanceau, J.P.; Bonillo, C.; Cotta, D' H.; Pepey, E.; Soler, L.; Rodier-Goud, M.; Hont, D' A.; Conte, M.A.; Bers, van N.E.M.; Penman, D.J.; Hitte, C.; Crooijmans, R.P.M.A.; Kocher, T.D.; Ozouf-Costaz, C.; Baroiller, J.F.; Galibert, F.

    2012-01-01

    Background: The Nile tilapia (Oreochromis niloticus) is the second most farmed fish species worldwide. It is also an important model for studies of fish physiology, particularly because of its broad tolerance to an array of environments. It is a good model to study evolutionary mechanisms in vertebr

  14. Dietary mannan oligosaccharide and Bacillus subtilis in diets for Nile tilapia (Oreochromis niloticus

    Directory of Open Access Journals (Sweden)

    Rafael Vieira de Azevedo

    2016-11-01

    Full Text Available A six week study was conducted to investigate the supplementation of prebiotic (Mannan oligosaccharide – MOS, from yeast Saccharomyces cerevisiae, probiotic (Bacillus subtilis – BS, C-3102 strain and their combination in diets for Nile tilapia. 192 fishes (4.03 ± 0.28 g were distributed into 16 tanks (40-L, in a completely randomized design (n=4. The following treatments were evaluated: control; prebiotic - 2 g MOS kg-1; probiotic - 2 g BS kg-1 and synbiotic - 1 g MOS kg-1 plus 1 g BS kg-1. Fishes fed diets pre-, pro- and synbiotic supplemented performed better in average daily gain, feed conversion rate, specific growth rate, protein efficiency ratio, carcass yield, total and standard length and body height than those maintained on control diets. The probiotic supplementation resulted in higher villus height and intestinal perimeter ratio than the control diet while the pre- and synbiotic supplementation in diets resulted in higher intestinal perimeter ratio. Carcass protein and ether extract were, respectively, higher and lower in fish fed synbiotic diets than other fish. The results of this study indicated that the mannan oligosaccharide and Bacillus subtilis supplementation, isolated or combined (synbiotic, could improve growth, body index, intestine morphometry and carcass composition in Nile tilapia.

  15. Digestible methionine + cystine requirement for Nile tilapia from 550 to 700 g

    Directory of Open Access Journals (Sweden)

    Mariana Michelato

    2013-01-01

    Full Text Available This trial was conducted to determine the dietary digestible methionine + cystine requirement of Nile tilapia (550 to 700 g based on the ideal protein concept. Six hundred fish were distributed in a completely randomized design with five treatments and four replicates, with 30 fish per experimental unit. The fish were fed diets containing approximately 262 g of digestible protein/kg, 3,040 kcal of digestible energy/kg and 7.90, 9.40, 10.90, 12.40 or 13.90 g of methionine + cystine/kg. The fish were hand-fed three times a day until apparent satiation for 30 days. No effects of dietary methionine + cystine on feed conversion ratio, daily protein deposition, whole body moisture, fillet moisture, crude protein, ether extract and ash, plasmatic HDL and LDL cholesterol were observed. Dietary methionine resulted in a linear increase in whole body protein and linear reduction in lipid deposition rate, hepatosomatic index, whole body ether extract and ash, plasmatic total cholesterol, plasmatic total lipids and plasmatic triglycerides. According to the Linear Response Plateau, the daily weight gain and fillet yield increased up to a level of 9.00 and 9.90 g methionine + cystine/kg of diet, respectively. The digestible methionine + cystine requirement of Nile tilapia is 9.00 g/kg for weight gain and 9.90 g/kg for fillet yield, corresponding to methionine + cystine:lysine ratios of 0.60 and 0.66, respectively.

  16. Arsenic-induced genotoxicity in Nile tilapia (Orechromis niloticus); the role of Spirulina platensis extract.

    Science.gov (United States)

    Sayed, Alaa El-Din H; Elbaghdady, Heba Allah M; Zahran, Eman

    2015-12-01

    Arsenic (As) is one of the most relevant environmental global single substance toxicants that have long been regarded as a carcinogenic and genotoxic potential. In this respect, we evaluated the cytogenetic effect of arsenic exposure in Nile tilapia (Oreochromis niloticus), in terms of erythrocyte alteration, apoptosis, and induction of micronuclei. Spirulina platensis (SP) is a filamentous cyanobacterium microalgae with potent dietary phytoantioxidant, anti-inflammatory, and anti-cancerous properties supplementation. The protective role of Spirulina as supplementary feeds was studied in Nile tilapia (O. niloticus) against arsenic-induced cytogenotoxicity. Four groups were assigned as control group (no SP or As), As group (exposed to water-born As in the form of NaAsO2 at 7 ppm), SP1 (SP at 7.5% + As at the same level of exposure), and SP2 (SP at 10% + As at the same level of exposure). As-treated group had a significant increase in all cytogenetic analyses including erythrocyte alteration, apoptosis, and induction of micronuclei after 2 weeks with continuous increase in response after 3 weeks. The combined treatment of Spirulina at two different concentrations of 7.5 and 10% had significantly declined the induction of erythrocyte alteration, apoptosis, and micronuclei formation induced by arsenic intoxication.

  17. Oxidative damage in gills and liver in Nile tilapia (Oreochromis niloticus) exposed to diazinon.

    Science.gov (United States)

    Toledo-Ibarra, G A; Díaz Resendiz, K J G; Ventura-Ramón, G H; González-Jaime, F; Vega-López, A; Becerril-Villanueva, E; Pavón, L; Girón-Pérez, M I

    2016-10-01

    Agricultural activity demands the use of pesticides for plague control and extermination. In that matter, diazinon is one of the most widely used organophosphorus pesticides (OPs). Despite its benefits, the use of OPs in agricultural activities can also have negative effects since the excessive use of these substances can represent a major contamination problem for water bodies and organisms that inhabit them. The aim of this paper was to evaluate oxidative damage in lipids and proteins of Nile tilapia (Oreochromis niloticus) exposed acutely to diazinon (0.97, 1.95 and 3.95ppm) for 12 or 24h. The evaluation of oxidative damage was determined by quantifying lipid hydroperoxides (Fox method) and oxidized proteins (DNPH method). The data from this study suggest that diazinon induces a concentration-dependent oxidative damage in proteins, but not lipids, of the liver and gills of Nile tilapia. Furthermore, the treatment leads to a decrease in the concentration of total proteins, which can have serious consequences in cell physiology and fish development.

  18. Digestible lysine requirement of Nile tilapia fingerlings fed arginine-tolysine-balanced diets

    Directory of Open Access Journals (Sweden)

    Wilson Massamitu Furuya

    2012-03-01

    Full Text Available This study was conducted to determine the digestible lysine requirements of Nile tilapia fingerlings. Fish (n = 300; average initial weight = 1.44 g were distributed 15 300-L aquariums, in a completely randomized design with five treatments and three replicates, and fed extruded diets containing 11.3, 13.7, 16.1, 18.4 or 20.8 g/kg of digestible lysine. The arginine:lysine ratio was maintained at 1.3:1. All fish were fed diets containing 281 g/kg of digestible protein and 3,372 kcal digestible energy/kg, hand-fed until apparent satiation. There was no effect of the dietary lysine levels on survival rate, or protein and ash body rates. With increasing levels of lysine in the diet, a quadratic effect on weight gain, feed conversion, protein efficiency ratio, protein deposition rate, deposition rate of fat, body moisture and body lipids was observed, where the best values of the variables were estimated at 15.96, 16.4, 14.35, 15.21, 15.87, 15.21 and 16.29 g/kg of lysine, respectively. The digestible lysine requirement of Nile tilapia fingerlings is 15.21 g/kg (5.41 g/100 g of digestible protein, in diets balanced for the arginine:lysine ratio.

  19. Production of hydrolysate from processed Nile tilapia (Oreochromis niloticus residues and assessment of its antioxidant activity

    Directory of Open Access Journals (Sweden)

    Daniela Miotto BERNARDI

    2016-01-01

    Full Text Available Abstract The objective of this work was to produce protein hydrolysates from by-products of the Nile tilapia fileting process, and to assess the effects of different hydrolysis times on the antioxidant activity of the hydrolysed animal-based protein, in free form and incorporated into a food matrix. Gutted tilapia heads and carcasses were hydrolysed by Alcalase® for different hydrolysis times producing six hydrolysates. The protein content, degree of hydrolysis, reverse-phase high-performance liquid chromatography, and antioxidant activity by the ORAC, FRAP and TEAC methods were analysed. Three mini-hamburger formulations were produced and the lipidic oxidation of mini-hamburger was determined by TBARS. The protein contained in the residue was completely recovered in the process. The hydrolysates varied in their degree of hydrolysis, but presented similar levels of antioxidant activity. In the mini-hamburgers the hydrolysate was capable of delaying oxidation after 7 days of storage. Hydrolysis of tilapia processing by-products produced peptides may be used in the formulation of functional foods.

  20. Metacercarial Infection of Wild Nile Tilapia (Oreochromis niloticus) from Brazil

    Science.gov (United States)

    Pinto, Hudson A.; Mati, Vitor L. T.; Melo, Alan L.

    2014-01-01

    Fingerlings of Oreochromis niloticus collected in an artificial urban lake from Belo Horizonte, Minas Gerais, Brazil, were evaluated for natural infection with trematodes. Morphological taxonomic identification of four fluke species was performed in O. niloticus examined, and the total prevalence of metacercariae was 60.7% (37/61). Centrocestus formosanus, a heterophyid found in the gills, was the species with the highest prevalence and mean intensity of infection (31.1% and 3.42 (1–42), resp.), followed by the diplostomid Austrodiplostomum compactum (29.5% and 1.27 (1-2)) recovered from the eyes. Metacercariae of Drepanocephalus sp. and Ribeiroia sp., both found in the oral cavity of the fish, were verified at low prevalences (8.2% and 1.6%, resp.) and intensities of infection (only one metacercaria of each of these species per fish). These species of trematodes are reported for the first time in O. niloticus from South America. The potential of occurrence of these parasites in tilapia farming and the control strategies are briefly discussed. PMID:25485302

  1. Pesticide residues in Nile tilapia (Oreochromis niloticus) and Nile perch (Lates niloticus) from Southern Lake Victoria, Tanzania

    Energy Technology Data Exchange (ETDEWEB)

    Henry, L. [Chemistry Department, University of Dar es Salaam. PO Box 35061, Dar es Salaam (Tanzania); Kishimba, M.A. [Chemistry Department, University of Dar es Salaam. PO Box 35061, Dar es Salaam (Tanzania)]. E-mail: kishimba@chem.udsm.ac.tz

    2006-03-15

    Nile tilapia (Oreochromis niloticus) and Nile perch (Lates niloticus) samples were collected from fish landing stations in nine riparian districts on the Tanzanian side of Lake Victoria and screened for residues of 64 organochlorine, organophosphorus, carbamate, and pyrethroid pesticides. The residue levels in the fish fillet were up to 0.003, 0.03 and 0.2 mg/kg fresh weight (0.7, 3.8 and 42 mg/kg lipid weight) of fenitrothion, DDT and endosulfan, respectively. Mean levels within sites were up to 0.002, 0.02 and 0.1 mg/kg fresh weight (0.5, 0.5 and 16 mg/kg lipid weight), respectively. The detection of higher levels of p,p'-DDT than the degradation products (p,p'-DDD and p,p'-DDE), and higher levels of endosulfan isomers ({alpha} and {beta}) than the sulphate, in fish samples, implied recent exposure of fish to DDT and endosulfan, respectively. Generally, most of the fish samples had residue levels above the average method detection limits (MDLs), but were within the calculated ADI. - Fish from Lake Victoria had relatively low pesticide levels.

  2. A qualitative ecological risk assessment of the invasive Nile tilapia, Oreochromis niloticus in a sub-tropical African river system (Limpopo River, South Africa)

    CSIR Research Space (South Africa)

    Zengeya, TA

    2013-01-01

    Full Text Available This study outlines the development of a qualitative risk assessment method and its application as a screening tool for determining the risk of establishment and spread of the invasive Nile tilapia, Oreochromis niloticus (Linnaeus, 1758), within...

  3. Morphometric Characters of Nile Tilapia (Oreochromis niloticus in Thailand

    Directory of Open Access Journals (Sweden)

    Piya KOSAI

    2014-02-01

    Full Text Available The present study is conducted to describe the morphometric characteristics of a Thailand strain of Oreochromis niloticus. The total length of the observed fish ranged from 7.96 - 17.36 cm. Body measurement and proportions are extensively used for identification of this species. The following 18 measurements are determined for each fish: Total length (TL; Standard length (SL; Body depth (BD; Pre-dorsal length (PDL; Pre-pectoral length (PPCL; Pre-pelvic length (PPVL; Pre-anal length (PAL; Depth of caudal peduncle (DCP; Length of caudal peduncle (LCP; Head length (HL; Eye diameter (ED; Snout length (SNL; Upper jaw length (UJL; Lower jaw length (LJL; Caudal fin length (CFL; Pectoral fin length (PFL; Length of dorsal fin base (LDFB; Length of anal fin base (LAFB. The rate of growth of different morphological body parts of the fish in relation to its total length is studied. Additionally, the total length and body weight relationship is found to be a straight line in logarithmic scale expressed as Log BW = 3.026 Log TL - 1.839. The value of regression co-efficient obtained for the length-weight relationship is 3.026. This finding suggests that selection for growth using this equation is a good alternative for measuring weight in the field, when accurate weighing balances are not available. Hence, the present study provides the information of the various body parts measurements of Tilapia and establishes mathematical equations relating to these various morphometric relationships which can be utilized for the conversion of one measurement into another.doi:10.14456/WJST.2014.76

  4. Effects of stocking density on production and economics of Nile tilapia (Oreochromis niloticus) and freshwater prawn (Macrobrachium rosenbergii) polyculture in periphyton-based systems

    NARCIS (Netherlands)

    Uddin, S.; Rahman, S.M.S.; Azim, M.E.; Wahab, M.A.; Verdegem, M.C.J.; Verreth, J.A.J.

    2007-01-01

    The present research investigated the effect of stocking density on pond (75 m2, depth 1.2 m) production of Nile tilapia (Oreochromis niloticus) and freshwater prawn (Macrobrachium rosenbergii) stocked at a fixed 3:1 tilapia:prawn ratio. Three stocking densities were tried in triplicate: 20 000 ha¿1

  5. Determining the cleavage site for the mature antimicrobial peptide of Nile tilapia β-defensin using 2D electrophoresis, western blot, and mass spectrometry analysis.

    Science.gov (United States)

    Chang, Chin-I; Chen, Li-Hao; Hu, Yeh-Fang; Wu, Chia-Che; Tsai, Jyh-Ming

    2017-03-01

    Several proteomic techniques were used to determine the cleavage site of the mature antimicrobial peptide of Nile tilapia β-defensin. The computer-predicted Nile tilapia β-defensin ((25)ASFPWSCLSLSGVCRKVCLPTELFFGPLGCGKGSLCCVSHFL(66)) composed of 42 amino acids was chemically synthesized and prepared to produce an antibody for Western blotting. Total proteins from the skin of the Nile tilapia were separated on two-dimensional electrophoresis, and the spot of Nile tilapia β-defensin was recognized using Western blot analysis. It was then excised and extracted from the gel. The precise molecular mass of this spot was determined by LC-MS/MS spectrometry. Four major peptides were discovered, with molecular weights of 4293.2 Da, 4306.5 Da, 4678.9 Da, and 4715.0 Da. The calculated mass of the 40-amino-acid sequence ((27)FPWSCLSLSGVCRKVCLPTELFFGPLGCGKGSLCCVSHFL(66)) of Nile tilapia β-defensin starting from Phe27 and ending with Leu66 was 4293.18 Da, which completely matched the 4293.2 Da peptide that was obtained from the mass spectrometry analysis. This result confirmed that the cleavage site for the mature C-terminal Nile tilapia β-defensin is at residue Ser26-Phe27, not at Ala24-25 as predicted by computer analysis. This study provides a simple but reliable model to determine the cleavage site for a mature antimicrobial peptide. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. Genetic differentiation among natural populations of the Nile tilapia Oreochromis niloticus (Teleostei, cichlidae).

    Science.gov (United States)

    Agnèse, J F; Adépo-Gourène, B; Abban, E K; Fermon, Y

    1997-07-01

    We analysed the genetic differentiation among 17 natural populations of the Nile tilapia Oreochromis niloticus (Linnaeus, 1758) using allozymes and restriction fragment length polymorphism (RFLP) of mitochondrial DNA (mtDNA). The populations studied, from the River Senegal to Lake Tana and from Lake Manzalla to Lake Baringo, represent all subspecies which have been previously described. Sixteen variable nuclear loci showed that these populations can be clustered in three groups: (1) West African populations (Senegal, Niger, Volta and Chad drainages), (2) Ethiopian Rift Valley populations (Lakes Awasa, Ziway, Koka and the Awash River) and (3) Nile drainage (Manzalla, Cairo, Lake Edward) and Kenyan Rift Valley populations (Lakes Turkana, Baringo and River Suguta). Nine different mtDNA haplotypes were found in the RFLP analysis of a 1 kb portion of the D-loop region. The network obtained showed that there are three geographically distinct groups; all West African populations and O. aureus are clustered, the two Ethiopian Rift Valley populations are distinct and between these two groups are the Kenyan and Ugandan Rift Valley populations. Nile populations show affinities both with West African populations and with specimens from Lakes Tana and Turkana. Taxonomic and biogeographical implications of these results are discussed.

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

    Directory of Open Access Journals (Sweden)

    Julia W. Pridgeon

    2014-05-01

    Full Text Available 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 6.1×10 4 and 1.1×10 7 CFU/fish, respectively, whereas that of flounder isolate A. hydrophila to channel catfish and Nile tilapia were 1.4×10 7 and 5.6×10 7 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.

  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. Two Myxobolus spp. infecting the kidney of Nile tilapia (Oreochromis niloticus) in the River Nile at Beni-Suef governorate, Egypt, and the associated renal changes.

    Science.gov (United States)

    Abdel-Baki, Abdel-Azeem S; Abdel-Haleem, Heba M; Sakran, Thabet; Zayed, Eman; Ibrahim, Khalid E; Al-Quraishy, Saleh

    2015-03-01

    Two Myxobolus spp. are described from the kidney of the Nile tilapia (Oreochromis niloticus) collected from the River Nile, Egypt. The prevalence of infection was 61 % (47/77), with the infected fish in each case parasitized by the two Myxobolus species simultaneously. The infection was exhibited as free spores in Bowman capsules and renal glomeruli, which makes their original structures difficult to discern. In some cases, the infection appeared as a fibrous plasmodia-like structure containing degenerated developmental stages and spores in the interstitium. The paper identifies each species based on the morphological characteristics of its spores and identifies the histological impacts of Myxobolus infection in this species of fish.

  10. Prebiotic (Mannanoligosaccharide- MOS in fish nutrition: effects on nile-tilapia Oreochromis niloticus performance

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    Flávio Endrigo Cechim

    2012-12-01

    Full Text Available World fish production are growing about 10% a year and Brazil presents potential to be the first one in fish production until 2030. However, intensification of aquaculture production systems expose fish to numerous stressors such as poor water quality, crowding, handling and transport which may negatively affect their growth and and limit profitability of aquaculture systems. This current setup favors the use of dietary prebiotics for management of farmed fish as environmentally friendly practice. This study was set out to determine de effects of increasing levels of mannanoligosccharides (MOS on growth of juvenile Nile tilapia (Oreochromis niloticus. Fish (12.62 ± 0.38 were randomly distributed into 16 cages (0.25m3 polyvinyl chloride; 20 fish per cage, inside four 5m3 net-cage at Salto Caxias Hydroeletric water reservoir (Boa Vista da Aparecida, PR. Fish were fed during 60 days with a commercial diet (32%CP supplemented with 0.0 (control; 0.2; 0.4 and 0.8% dietary MOS (n=4. Water quality parameters (temperature, pH and dissolved oxygen were monitored during trial. After 60 days feeding trial, fish were fasted for 24 hours and sedated for biometrical parameters to evaluate growth parameters. It was observed no influence (p>0.05 of MOS supplementation on Nile tilapia growth parameters (weight gain, feed conversion rate, specific growth rate as well as for hepatosomatic index. Fish fed 0.4% dietary MOS showed increased (p<0.05 feed consumption (76.74 ± 3.98 when compared to fish fed control (unsupplemented diet (69.31 ± 1.11. MOS are indigestible glucomannoproteins, which provide mannose substrate upon which pathogenic gut bacteria selectively attach and prevents formation of mixed colonies leading to better gut health by increasing regularity, height and integrity of the gut villi and consequent better utilization and absorption of nutrients. Several authors found positive effects of MOS supplementation on fish growth and at same time, others

  11. Dietary levels of Mannanoligosaccharide (MOS for nile-tilapia (Oreochromis niloticus: Intestinal Morphology

    Directory of Open Access Journals (Sweden)

    Flavio Endrigo Cechim

    2012-12-01

    Full Text Available Intensification of aquaculture production systems exposes fish to numerous stressors, which may negatively affect their growth and limit profitability of aquaculture systems. In addition, fish farmers are now obliged to conform to Best Management Practices (BPMs regulations. This current setup favors the use of dietary prebiotics for management of farmed fish as environmentally friendly practice. Mannanoligosaccharides (MOS are complex carbohydrates derived from yeast (Saccharomyces cerevisiae cell walls. This study was set out to evaluate the effects of increasing levels of dietary MOS on intestinal morphology of Nile-tilapia. Fish (12.62 ± 0.38 were randomly distributed into 16 cages (0.25m3 polyvinyl chloride; 20 fish per cage, inside four 5m3 net-cage at Salto Caxias Hydroeletric water reservoir (Boa Vista da Aparecida, PR and fed diets containing increasing levels of MOS (0.0; 0.2; 0.4 and 0.8% during 30 days (n=4. The proximal intestine fragment of two specimens from each replicate was taken for histological observations. The histological sections (5 μm were stained with haematoxylin and eosin (H & E and documented photographically with a digital camera (DCM 130E digital camera for microscope 1.3 pixels, CMOS chip Software Scopephoto connected to a light microscope (EDUTEC 502 AC. The images were analyzed by using (BEL Eurisko software for intestinal villi measures. Water quality parameters (temperature, pH and dissolved oxygen were monitored during trial. It was observed influence (p<0.05 of MOS supplementation on Nile tilapia intestinal morphology. Fish fed diet containing 0.4% MOS supplementation showed increased (p<0.05 villi height (436.98±66.81 μm when compared to fish fed unsupplemented control diet (401.01±70.73 μm, 0.2% (364.59±61.68 μm and 0.8% (404.08±61.62 μm. Mannanoligosaccharides (MOS are complex carbohydrates derived from yeast (Saccharomyces cerevisiae cell walls and present mannose as primary carbohydrate

  12. Quantification of essential fatty acids in the heads of nile tilapia (Oreochromis niloticus) fed with linseed oil

    OpenAIRE

    Aguiar,Ana C.; Cottica,Solange M.; Boroski,Marcela; Oliveira,Cláudio C.; Bonafé,Elton G.; França,Polyana B.; Souza,Nilson E.; Visentainer,Jesui V.

    2011-01-01

    The objective of this study was to examine the effects of linseed oil on n-6 and n-3 polyunsaturated (PUFA) fatty acid content in the heads of Nile tilapia (Oreochromis niloticus), these are normally discarded during the filleting process. The quantification of PUFA was carried out in absolute weights through the use of methyl ester (23:0), as an internal standard, and TCFx (theoretical FID correction factor) by GC gas chromatography. Tilapias were given diets with increasing levels (0.00, 1....

  13. A high-resolution map of the Nile tilapia genome: a resource for studying cichlids and other percomorphs

    Directory of Open Access Journals (Sweden)

    Guyon Richard

    2012-06-01

    Full Text Available Abstract Background The Nile tilapia (Oreochromis niloticus is the second most farmed fish species worldwide. It is also an important model for studies of fish physiology, particularly because of its broad tolerance to an array of environments. It is a good model to study evolutionary mechanisms in vertebrates, because of its close relationship to haplochromine cichlids, which have undergone rapid speciation in East Africa. The existing genomic resources for Nile tilapia include a genetic map, BAC end sequences and ESTs, but comparative genome analysis and maps of quantitative trait loci (QTL are still limited. Results We have constructed a high-resolution radiation hybrid (RH panel for the Nile tilapia and genotyped 1358 markers consisting of 850 genes, 82 markers corresponding to BAC end sequences, 154 microsatellites and 272 single nucleotide polymorphisms (SNPs. From these, 1296 markers could be associated in 81 RH groups, while 62 were not linked. The total size of the RH map is 34,084 cR3500 and 937,310 kb. It covers 88% of the entire genome with an estimated inter-marker distance of 742 Kb. Mapping of microsatellites enabled integration to the genetic map. We have merged LG8 and LG24 into a single linkage group, and confirmed that LG16-LG21 are also merged. The orientation and association of RH groups to each chromosome and LG was confirmed by chromosomal in situ hybridizations (FISH of 55 BACs. Fifty RH groups were localized on the 22 chromosomes while 31 remained small orphan groups. Synteny relationships were determined between Nile tilapia, stickleback, medaka and pufferfish. Conclusion The RH map and associated FISH map provide a valuable gene-ordered resource for gene mapping and QTL studies. All genetic linkage groups with their corresponding RH groups now have a corresponding chromosome which can be identified in the karyotype. Placement of conserved segments indicated that multiple inter-chromosomal rearrangements have occurred

  14. Immunologic parameters evaluations in Nile tilapia (Oreochromis niloticus) exposed to sublethal concentrations of diazinon.

    Science.gov (United States)

    Girón-Pérez, M I; Velázquez-Fernández, J; Díaz-Resendiz, K; Díaz-Salas, F; Canto-Montero, C; Medina-Díaz, I; Robledo-Marenco, M; Rojas-García, A; Zaitseva, G

    2009-08-01

    Fish resistance to microorganisms depends basically on the immune response. Although there are several studies on the diazinon mammalian immunotoxicity, in the case of fish there are only few. The aim of present study was to evaluate the effect of diazinon on immunological parameters (relative spleen weight, splenocytes count, lysozyme activity, respiratory burst and IgM concentration) in Nile tilapia. Diazinon at sublethal concentrations (0.39 and 0.78 mg/L) did not alter RSW, splenocytes count or lysozyme activity. However, at the highest concentration tested (1.96 mg/L) diazinon significantly increased respiratory burst and IgM concentration. In summary, diazinon (and perhaps other pesticides) could alter immunological response and induce oxidative stress.

  15. Effect of the hydrostatic pressure on otolith growth of early juveniles of Nile tilapia Oreochromis niloticus.

    Science.gov (United States)

    Correia, A T; Coimbra, A M; Damasceno-Oliveira, A

    2012-07-01

    Nile tilapia Oreochromis niloticus early juveniles were maintained for 2 weeks in a pressurized system under a controlled photoperiod, at constant salinity and temperature. Groups of fish were exposed to one of three absolute hydrostatic pressure (HP) regimes: (1) a constant normal atmospheric pressure (100 kPa), (2) a constant 40 m pressure (500 kPa) or (3) a semi-diurnal cyclic vertical migration (100-500 kPa). No significant differences were detected in otolith size and incremental periodicity among the three HP treatments, suggesting that HP does not affect otolith growth of early juveniles O. niloticus. © 2012 The Authors. Journal of Fish Biology © 2012 The Fisheries Society of the British Isles.

  16. Isolation and characterization of bacteria with antibacterial properties from Nile tilapia (Oreochromis niloticus).

    Science.gov (United States)

    Etyemez, Miray; Balcazar, Jose Luis

    2016-04-01

    One hundred and twenty bacterial isolates were obtained from the intestinal mucus of Nile tilapia (Oreochromis niloticus) and screened for antagonistic activity and adherence abilities. Based on in vitro antagonism against two pathogens (Streptococcus iniae and Edwardsiella piscicida), five isolates were selected and identified by 16S rRNA gene sequence analysis. All antagonistic isolates were affiliated to the genus Bacillus, which showed inhibitory activity against S. iniae. Only the isolate B191 (closely related to Bacillus mojavensis) inhibited the growth of both pathogens. Moreover, isolate B191 adhered significantly better to fish intestinal mucus than other antagonistic isolates. According to our results, these bacterial isolates, particularly isolate B191, should be further studied to explore their probiotic effects under in vivo conditions.

  17. PERFORMANCE OF NILE TILAPIA (OREOCHROMIS NILOTICUS FED FISH MEAL AND POULTRY BY-PRODUCT

    Directory of Open Access Journals (Sweden)

    H.M. ADAM SULIEMAN

    2011-11-01

    Full Text Available This study was conducted at the Department of Fisheries and Wild life Science, College of Science and Technology of Animal Production, Sudan University of Science and Technology, to determine the feed efficiency of two locally formulated diets (A and B on performance of Nile Tilapia (Oreochromis niloticus. Two iso-caloric iso-nitrogenus diets were formulated by adding 60% wheat bran, 30% cotton seed cake and 10% poultry by-product (offal+intestine, while the diet (B contained 60% wheat bran, 30% cotton seed cake and 10% fish meal. The fish were fed twice a day at affixed feeding rate of 5% body weight of fish per day for 90 days. The total body weight, total length and standard length were measured every 10 days throughout the experimental period. The growth response and performance data of the studied fish (Oreochromis niloticus fed with diet (B containing fishmeal recorded a better growth response than that fish fed poultry by- product meal (diet A. The final weight increment, specific growth rate (SGR, feed conversion ratio (FCR and protein efficiency ratio (PER over the experimental period showed lowest value for the group fed the diet with poultry by-product (Diet A compared to those fed with the fishmeal (Diet B. Except the apparent protein utilization (APU was recorded higher for those fed with Diet A (23.31 than Diet B (11.99. The groups fed diet (A attained SGR 0.24, FCR 1.9, PER 0.75, APU 23.31, while it recorded in group (B, SGR 0.34, FCR 1.2, PER 1.06, APU 11.99. Therefore, fish meal is better as compared to poultry by-products for Nile Tilapia (Oreochromis niloticus nutrition.

  18. Hematology of Nile tilapia (Oreochromis niloticus subjected to anesthesia and anticoagulation protocols

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    Nadia Cristine Weinert

    2015-12-01

    Full Text Available Clinical hematology facilitates the diagnosis of disease and can act as a prognostic indicator of pathological conditions in fish. The aim of the present study was to evaluate hematological parameters of Nile tilapia (Oreochromis niloticus subjected to different anesthetics and anticoagulants. Thirty apparently healthy fishes (average weight of 473 ± 35. 50 g and mean total length of 29. 33 ± 0. 37 cm, were selected from the local commercial fish farm in the Lages municipality (Santa Catarina, Brazil. The animals were randomly divided into three groups of 10. In two groups, anesthesia was induced with eugenol (70 mg·L- 1 (EG and Benzocaine hydrochloride (100 mg·L-1 (BG, respectively. Anesthesia was not administered to fish of the third group (CG/control group. Blood samples were obtained by venipuncture of the caudal vessels and placed into microtubes containing sodium heparin or Na2EDTA for further analysis. The results were analyzed by Sigma Stat for Windows, the paired t-test for significant differences between anticoagulants of the same group, and analysis of variance followed by the Tukey test for comparison of means between groups (p ? 0. 05. Most of the observed changes in the erythrogram were significantly higher for the anticoagulant heparin and benzocaine group in comparison to the control group. However, the values obtained for the leukogram were significantly higher for all groups subjected to the Na2EDTA anticoagulant, suggesting that heparin may cause cell clumping. The results suggest that the anesthetics under investigation effectively minimizes the effects of stress caused by handling and invasive procedures, and that the anticoagulant heparin causes less hemolysis in comparison to Na2EDTA for Nile tilapia. Thus, the hematological variations attributed to different anesthetic protocols and/or different anticoagulants should be considered for the species Oreochromis niloticus.

  19. Effects of dietary inclusions of oilseed meals on physical characteristics and feed intake of diets for the Nile Tilapia, Oreochromis niloticus

    DEFF Research Database (Denmark)

    Obirikorang, Kwasi Adu; Amisah, Stephen; Fialor, Simon Cudjoe;

    2015-01-01

    The present study investigated the effects of the inclusion of three oilseed by-products (soybean, copra and palm kernel meals) on some physical characteristics of pelletized feeds as well as on voluntary feed intake and faecal matter production by the Nile tilapia, Oreochromis niloticus. The die......The present study investigated the effects of the inclusion of three oilseed by-products (soybean, copra and palm kernel meals) on some physical characteristics of pelletized feeds as well as on voluntary feed intake and faecal matter production by the Nile tilapia, Oreochromis niloticus......) was significantly higher in the tilapia groups fed the copra and palm kernel meals. The results obtained from this study show that 30% inclusions of unrefined forms of copra and palm kernel meal in Nile tilapia diets is possible, without adversely affecting feed intake or pellet nutrient losses prior to ingestion....

  20. Performance and economic analysis of the production of Nile tilapia submitted to different feeding management

    Directory of Open Access Journals (Sweden)

    Érica Bevitorio Passinato

    2015-12-01

    Full Text Available The productive performance and the variable cost of production were evaluated for different feeding strategies for tilapia during the production cycle. A sample of 2,000 juvenile tilapia was distributed (23.55 ± 2.38 g into five treatments and with four repetitions as follows: C (feed consumption to apparent satiety, R20 (beginning feed restriction when fish reached an average weight of 20 g, R200 (beginning feed restriction when fish reached an average weight of 200 g, R400 (beginning feed restriction when fish reached an average weight of 400 g and R600 (beginning feed restriction when fish reached an average weight of 600 g. The fish were given extruded commercial feed containing 34% crude protein until they reached a weight of 200 g, at which time they received feed containing 32% crude protein. Monthly biometrics were performed in order to determine the food restriction starting point, which was one day of restriction followed by six feeding days. The following parameters were evaluated: water quality, productive performance variables, the variable costs of production and excreted nitrogen. The results were subjected to analysis of variance, and the means were compared using Tukey’s test (5% significance. No statistical differences were observed in final weight, weight gain, feed consumption, feed conversion or survival. The fish from the R20 treatment had the lowest variable cost of production (g fish-1 and the lowest nitrogen excretion into the water. This suggests that feed restriction from the early stages of life does not compromise the productive performance and contributes to reducing the variable costs and the quantity of nitrogen excreted into the environment. Thus, a one-day per week feed restriction strategy can be applied from the earliest stages of life without compromising the productive performance or body composition of Nile tilapia. This strategy can also reduce variable costs of production by means of reducing relative

  1. Blocking of progestin action disrupts spermatogenesis in Nile tilapia (Oreochromis niloticus).

    Science.gov (United States)

    Liu, Gang; Luo, Feng; Song, Qiang; Wu, Limin; Qiu, Yongxiu; Shi, Hongjuan; Wang, Deshou; Zhou, Linyan

    2014-08-01

    In vitro studies have indicated that the maturation-inducing hormone 17α,20β-dihydroxy-4-pregnen-3-one (17α,20β-DP, DHP), probably through nuclear progestin receptor (Pgr), might be involved in the proliferation of spermatogonial cells and the initiation of meiosis in several fish species. However, further in vivo evidence is required to elucidate the role of DHP in spermatogenesis during sexual differentiation in teleosts. In this study, we cloned pgr and analyzed its expression in Nile tilapia (Oreochromis niloticus) and treated XY fish with RU486 (a synthetic Pgr antagonist) from 5 days after hatching (dah) to determine the role of DHP in spermatogenesis. Sequence and phylogenetic analyses revealed that the Pgr identified in tilapia is a genuine Pgr. Pgr was found to be expressed in the Sertoli cells surrounding spermatogonia and spermatids in the testis of tilapia. Real-time PCR analysis revealed that the expression of pgr in the testis was significantly upregulated from 10 dah, further increased at 50 dah, and persisted until adulthood in fish. In the testis of RU486-treated fish, the transcript levels of germ cell markers and a meiotic marker were substantially reduced. However, the expression of markers in Sertoli cells remained unchanged. Moreover, the production of 11-ketotestosterone and the expression of genes encoding various steroidogenic enzymes were also not altered. In contrast, the expression of cyp17a2, encoding one of the critical steroidogenic enzymes involved in DHP biosynthesis, declined significantly, possibly indicating the inhibition of DHP production by RU486. RU486 treatment given for 2 months did not affect spermatogenesis; however, treatment given for more than 3 months resulted in a decrease in spermatogonial cell numbers and depletion of later-phase spermatogenic cells. Simultaneous excessive DHP supplementation restored spermatogenesis in RU486-treated XY fish. Taken together, our data further indicated that DHP, possibly through

  2. Five different piscidins from Nile tilapia, Oreochromis niloticus: analysis of their expressions and biological functions.

    Directory of Open Access Journals (Sweden)

    Kuan-Chieh Peng

    Full Text Available Piscidins are antimicrobial peptides (AMPs that play important roles in helping fish resist pathogenic infections. Through comparisons of tilapia EST clones, the coding sequences of five piscidin-like AMPs (named TP1∼5 of Nile tilapia, Oreochromis niloticus, were determined. The complete piscidin coding sequences of TP1, -2, -3, -4, and -5 were respectively composed of 207, 234, 231, 270, and 195 bases, and each contained a translated region of 68, 77, 76, 89, and 64 amino acids. The tissue-specific, Vibrio vulnificus stimulation-specific, and Streptococcus agalactiae stimulation-specific expressions of TP2, -3, and -4 mRNA were determined by a comparative RT-PCR. Results of the tissue distribution analysis revealed high expression levels of TP2 mRNA in the skin, head kidneys, liver, and spleen. To study bacterial stimulation, S. agalactiae (SA47 was injected, and the TP4 transcript was upregulated by >13-fold (compared to the wild-type (WT control, without injection and was 60-fold upregulated (compared to the WT control, without injection 24 h after the S. agalactiae (SA47 injection in the spleen and gills. Synthesized TP3 and TP4 peptides showed antimicrobial activities against several bacteria in this study, while the synthesized TP1, -2, and -5 peptides did not. The synthesized TP2, -3, and -4 peptides showed hemolytic activities and synthesized TP3 and TP4 peptides inhibited tilapia ovary cell proliferation with a dose-dependent effect. In summary, the amphiphilic α-helical cationic peptides of TP3 and TP4 may represent novel and potential antimicrobial agents for further peptide drug development.

  3. Body composition and compensatory growth in Nile tilapia Oreochromis niloticus under different feeding intervals

    Science.gov (United States)

    Gao, Yang; Wang, Ziwei; Hur, Jun-wook; Lee, Jeong-Yeol

    2015-07-01

    We investigated the growth and body composition of Nile tilapia under five different feeding regimes. A control group was fed to satiation twice daily for 185 days; four treatment groups were fed at intervals of 2, 3, 4 or 7 days (dietary `restricted' period, days 0-80) and then fed to satiation (`refeeding' period, days 80-185). Compensatory growth in weight and length of the feed-restricted groups was observed during the refeeding period. However, the growth of none of the restricted groups caught up with that of the control group over the experimental period. Feed intake upon refeeding increased with the duration of deprivation. There were no significant differences in feed efficiency between the restricted and control groups during the refeeding stage, suggesting that hyperphagia was the mechanism responsible for the increased growth rates during this period. Tilapia preferentially used n-3 polyunsaturated fatty acids and nonessential amino acids during the restricted-feeding period. Higher production was achieved by higher feed consumption. We suggest that if attainment of market size in minimum time is required, fish should be consistently fed to satiation, while taking care to avoid the possible negative consequences of overfeeding.

  4. Estrogenic activities of diuron metabolites in female Nile tilapia (Oreochromis niloticus).

    Science.gov (United States)

    Pereira, Thiago Scremin Boscolo; Boscolo, Camila Nomura Pereira; Felício, Andreia Arantes; Batlouni, Sergio Ricardo; Schlenk, Daniel; de Almeida, Eduardo Alves

    2016-03-01

    Some endocrine disrupting chemicals (EDCs) can alter the estrogenic activities of the organism by directly interacting with estrogen receptors (ER) or indirectly through the hypothalamus-pituitary-gonadal axis. Recent studies in male Nile tilapia (Oreochromis niloticus) indicated that diuron may have anti-androgenic activity augmented by biotransformation. In this study, the effects of diuron and three of its metabolites were evaluated in female tilapia. Sexually mature female fish were exposed for 25 days to diuron, as well as to its metabolites 3,4-dichloroaniline (DCA), 3,4-dichlorophenylurea (DCPU) and 3,4-dichlorophenyl-N-methylurea (DCPMU), at concentrations of 100 ng/L. Diuron metabolites caused increases in E2 plasma levels, gonadosomatic indices and in the percentage of final vitellogenic oocytes. Moreover, diuron and its metabolites caused a decrease in germinative cells. Significant differences in plasma concentrations of the estrogen precursor and gonadal regulator17α-hydroxyprogesterone (17α-OHP) were not observed. These results show that diuron metabolites had estrogenic effects potentially mediated through enhanced estradiol biosynthesis and accelerated the ovarian development of O. niloticus females.

  5. Haematology and melanoma crophage centers of Nile tilapia fed supplemented diet with propolis

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    Jerko Ledic-Neto

    2014-05-01

    Full Text Available The objective of this study was to investigate the influence of dietary supplementation with propolis on hematology and number and area of melanomacrophage centers in spleen and kidney of tilapia. After acclimation, fish (24.7 ± 7.4 gmean weight were distributed in 6 tanks 100 L, 6 fish per tank, in triplicate, at a temperature 24.0 ± 2.8oC, with two treatments: Fish fed 2% propolis supplemented diet and fish fed non-supplemented diet. To monitor the evolution of the effects, two samples were collected: half of the fish from each treatment were used after 15 days and the other half after 21, composing two feeding times. After each feeding time, blood, spleen and kidney were collected. After twenty one days feeding on 2% propolis supplemented diet, fish showed a lower number of total leukocytes and lymphocytes and an increase in the total erythrocytes number. Fish fed supplemented diet presented an increased number of melanomacrophage centers. We observed hemosiderin in all spleen samples. Kidney showed no significant difference on the presence of melanomacrophage centers containing hemosiderin. Despite these changes, the fish health status was not affected. The results showed that propolis supplementation in the diet ofNile tilapia may be physiologically feasible.

  6. Apparent digestibility of nutrients, energy, and amino acid of nontoxic and detoxified physic nut cakes for Nile tilapia

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    Hamilton Hisano

    2015-09-01

    Full Text Available Abstract:The objective of this work was to evaluate the apparent digestibility coefficients of nutrients, energy, and amino acids of nontoxic and detoxified physic nut cakes treated with solvent plus posterior extrusion, for Nile tilapia. The apparent digestibility coefficients of crude protein and gross energy were higher for detoxified than for nontoxic physic nut cake. However, the apparent digestibility coefficient of ether extract of the nontoxic physic nut cake was higher than that of the detoxified one. The apparent digestibility coefficient of amino acids of both feed ingredients was superior to 80%, except for glycine, for the nontoxic psychic nut cake, and for threonine, for the detoxified one. Nontoxic and detoxified physic nut cakes show apparent digestibility coefficient values equivalent to those of the other evaluated oilseeds and potential for inclusion in Nile tilapia diets.

  7. Ecotoxicological effects of carbofuran and oxidised multiwalled carbon nanotubes on the freshwater fish Nile tilapia: nanotubes enhance pesticide ecotoxicity.

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    Campos-Garcia, Janaína; Martinez, Diego Stéfani T; Alves, Oswaldo L; Leonardo, Antônio Fernando Gervásio; Barbieri, Edison

    2015-01-01

    The interactions of carbon nanotubes with pesticides, such as carbofuran, classical contaminants (e.g., pesticides, polyaromatic hydrocarbons, heavy metals, and dyes) and emerging contaminants, including endocrine disruptors, are critical components of the environmental risks of this important class of carbon-based nanomaterials. In this work, we studied the modulation of acute carbofuran toxicity to the freshwater fish Nile tilapia (Oreochromis niloticus) by nitric acid treated multiwalled carbon nanotubes, termed HNO3-MWCNT. Nitric acid oxidation is a common chemical method employed for the purification, functionalisation and aqueous dispersion of carbon nanotubes. HNO3-MWCNT were not toxic to Nile tilapia at concentrations ranging from 0.1 to 3.0 mg/L for exposure times of up to 96 h. After 24, 48, 72 and 96 h, the LC50 values of carbofuran were 4.0, 3.2, 3.0 and 2.4 mg/mL, respectively. To evaluate the influence of carbofuran-nanotube interactions on ecotoxicity, we exposed the Nile tilapia to different concentrations of carbofuran mixed together with a non-toxic concentration of HNO3-MWCNT (1.0 mg/L). After 24, 48, 72, and 96 h of exposure, the LC50 values of carbofuran plus nanotubes were 3.7, 1.6, 0.7 and 0.5 mg/L, respectively. These results demonstrate that HNO3-MWCNT potentiate the acute toxicity of carbofuran, leading to a more than five-fold increase in the LC50 values. Furthermore, the exposure of Nile tilapia to carbofuran plus nanotubes led to decreases in both oxygen consumption and swimming capacity compared to the control. These findings indicate that carbon nanotubes could act as pesticide carriers affecting fish survival, metabolism and behaviour.

  8. Molecular and functional characterization of CD59 from Nile tilapia (Oreochromis niloticus) involved in the immune response to Streptococcus agalactiae.

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    Gan, Zhen; Wang, Bei; Zhou, Wei; Lu, Yishan; Zhu, Weiwei; Tang, Jufen; Jian, JiChang; Wu, Zaohe

    2015-05-01

    CD59, the major inhibitor of membrane attack complex, plays a crucial role in regulation of complement activation. In this paper, a CD59 gene of Nile tilapia, Oreochromis niloticus (designated as On-CD59) was cloned and its expression pattern under the stimulation of Streptococcus agalactiae was investigated. Sequence analysis showed main structural features required for complement-inhibitory activity were detected in the deduced amino acid sequence of On-CD59. In healthy Nile tilapia, the On-CD59 transcripts could be detected in all the examined tissues, with the most abundant expression in the brain. When immunized with inactivated S. agalactiae, there was a clear time-dependent expression pattern of On-CD59 in the skin, brain, head kidney, thymus and spleen, with quite different kinetic expressions. The assays for the complement-inhibitory activity suggested that recombinant On-CD59 protein had a species-selective inhibition of complement. Moreover, our works showed that recombinant On-CD59 protein may possess both binding activities to PGN and LTA and inhibiting activity of S. agalactiae. These findings indicated that On-CD59 may play important roles in the immune response to S. agalactiae in Nile tilapia.

  9. Molecular Cloning and Expression Analysis of IgD in Nile Tilapia (Oreochromis niloticus) in Response to Streptococcus agalactiae Stimulus.

    Science.gov (United States)

    Wang, Bei; Wang, Pei; Wu, Zao-He; Lu, Yi-Shan; Wang, Zhong-Liang; Jian, Ji-Chang

    2016-03-08

    IgD is considered to be a recently-evolved Ig and a puzzling molecule, being previously found in all vertebrate taxa, except for birds. Although IgD likely plays an important role in vertebrate immune responses, the function of IgD in Nile tilapia (Oreochromis niloticus) is virtually unknown. In the present study, a membrane form of IgD (mIgD) heavy chains were cloned from the GIFT strain of Nile tilapia (designated On-mIgD). The On-mIgD heavy chain's cDNA is composed of 3347 bp with a 31 bp of 5'-UTR, 3015 bp open reading frame (ORF) and 301 bp 3'-UTR, encoding a polypeptide of 1004 amino acids (GenBank accession no: KF530821). Phylogenetic analysis revealed that On-mIgD heavy chains showed the highest similarity to Siniperca chuatsi. Quantitative real-time PCR (qRT-PCR) analysis showed that On-mIgD expression occurred predominately in head kidney, thymus, spleen, and kidney. After Streptococcus agalactiae infection, transcripts of On-mIgD increased and reached its peak at 48 h in the head kidney and thymus, and 72 h in the spleen, respectively. Taken together, these results collectively indicated that IgD could possibly have a key role to play in the immune response when bacterial infections in Nile tilapia.

  10. Defining a breeding objective for Nile tilapia that takes into account the diversity of smallholder production systems.

    Science.gov (United States)

    Omasaki, S K; van Arendonk, J A M; Kahi, A K; Komen, H

    2016-10-01

    In general, livestock and fish farming systems in developing countries tend to be highly diverse in terms of agro-ecological conditions and market orientation. There are no studies that have investigated if and how this diversity translates to varying preferences for breeding objective traits. This is particularly important for breeding programmes that are organized on a national level (e.g. government-supported nucleus breeding programmes). The aim of this study was to investigate whether Nile tilapia farmers with diverse production systems and economic constraints have different preferences for breeding objective traits. The second objective was to derive a consensus breeding goal, using weighted goal programming that could be used for a national breeding programme for Nile tilapia. A survey was conducted among 100 smallholder Nile tilapia farmers in Kenya to obtain preference values for traits of economic importance, by using multiple pairwise comparisons. Individual and group preference values were estimated using analytical hierarchy process. Low-income farmers preferred harvest weight, while medium- and high-income farmers preferred growth rate and survival. Grouping farmers according to market objective (fingerling production or fattening) showed that fingerling producers preferred growth rate and survival, while fattening farmers preferred harvest weight, height and thickness. Weighted goal programming was used to obtain consensus preference values, and these were used to derive desired gains for a breeding goal of a national breeding programme that takes into account the diversity of smallholder production systems.

  11. Additive genetic variation in resistance of Nile tilapia (Oreochromis niloticus) to Streptococcus iniae and S. agalactiae capsular type Ib: is genetic resistance correlated?

    Science.gov (United States)

    Streptococcus (S.) iniae and S. agalactiae are both economically important Gram positive bacterial pathogens affecting the globally farmed tilapia (Oreochromis spp.). Historically control of these bacteria in tilapia culture has included biosecurity, therapeutants and vaccination strategies. Genet...

  12. Increasing of temperature induces pathogenicity of Streptococcus agalactiae and the up-regulation of inflammatory related genes in infected Nile tilapia (Oreochromis niloticus).

    Science.gov (United States)

    Kayansamruaj, Pattanapon; Pirarat, Nopadon; Hirono, Ikuo; Rodkhum, Channarong

    2014-08-06

    Temperature strongly affects the health of aquatic poikilotherms. In Nile tilapia (Oreochromis niloticus), elevated water temperatures increase the severity of streptococcosis. Here we investigated the effects of temperature on the vulnerability and inflammatory response of Nile tilapia to Streptococcus agalactiae (Group B streptococci; GBS). At 35 and 28 °C, GBS took 4 and 7h, respectively to reach the log-phase and, when incubated with tilapia whole blood, experienced survival rates of 97% and 2%, respectively. The hemolysis activity of GBS grown at 35 °C was five times higher than that of GBS grown at 28 °C. GBS expressed cylE (β-hemolysin/cytolysin), cfb (CAMP factor) and PI-2b (pili-backbone) much more strongly at 35 °C than at 28 °C. Challenging Nile tilapia reared at 35 and 28 °C with GBS resulted in accumulated mortalities of about 85% and 45%, respectively. At 35 °C, infected tilapia exhibited tremendous inflammatory responses due to a dramatic up-regulation (30-40-fold) of inflammatory-related genes (cyclooxygenase-2, IL-1β and TNF-α) between 6 and 96 h-post infection. These results suggest that the increase of GBS pathogenicity to Nile tilapia induced by elevated temperature is associated with massive inflammatory responses, which may lead to acute mortality.

  13. Effect of dietary genistein on growth performance, digestive enzyme activity, and body composition of Nile tilapia Oreochromis niloticus

    Science.gov (United States)

    Chen, Dong; Wang, Wei; Ru, Shaoguo

    2015-01-01

    An 8-week feeding experiment was performed to evaluate the effect of dietary genistein on growth performance, body composition, and digestive enzymes activity of juvenile Nile tilapia ( Oreochromis niloticus). Four isonitrogenous and isoenergetic diets were formulated containing four graded supplements of genistein: 0, 30, 300, and 3 000 μg/g. Each diet was randomly assigned in triplicate to tanks stocked with 15 juvenile tilapia (10.47±1.24 g). The results show that 30 and 300 μg/g dietary genistein had no significant effect on growth performance of Nile tilapia, but the higher level of genistein (3 000 μg/g) significantly depressed the final body weight and specific growth rate. There was no significant difference in survival rate, feed intake, feed efficiency ratio or whole body composition among all dietary treatments. An assay of digestive enzymes showed that the diet containing 3 000 μg/ggenistein decreased stomach and hepatopancreas protease activity, and amylase activity in the liver and intestine, while a dietary level of 300 μg/g genistein depressed stomach protease and intestine amylase activities. However, no significant difference in stomach amylase activity was found among dietary treatments. Overall, the results of the present study indicate that a high level of dietary genistein (3 000 μg/g, or above) would significantly reduce the growth of Nile tilapia, partly because of its inhibitory effect on the activity of major digestive enzymes. Accordingly, the detrimental effects of genistein, as found in soybean products, should not be ignored when applied as an alternative ingredient source in aquaculture.

  14. Thyroid Hormone Upregulates Hypothalamic kiss2 Gene in the Male Nile Tilapia, Oreochromis niloticus

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    Satoshi eOgawa

    2013-11-01

    Full Text Available Kisspeptin has recently been recognized as a critical regulator of reproductive function in vertebrates. During the sexual development, kisspeptin neurons receive sex steroids feedback to trigger gonadotropin-releasing hormone (GnRH neurons. In teleosts, a positive correlation has been found between the thyroid status and the reproductive status. However, the role of thyroid hormone in the regulation of kisspeptin system remains unknown. We cloned and characterized a gene encoding kisspeptin (kiss2 in a cichlid fish, the Nile tilapia (Oreochromis niloticus. Expression of kiss2 mRNA in the brain was analyzed by in situ hybridization. The effect of thyroid hormone (triiodothyronine, T3 and hypothyroidism with methimazole (MMI on kiss2 and the three GnRH types (gnrh1, gnrh2 and gnrh3 mRNA expression was analyzed by real-time PCR. Expression of thyroid hormone receptor mRNAs were analyzed in laser-captured kisspeptin and GnRH neurons by RT-PCR. The kiss2 mRNA expressing cells were seen in the nucleus of the lateral recess in the hypothalamus. Intraperitoneal administration of T3 (5µg/g body weight to sexually mature male tilapia significantly increased kiss2 and gnrh1 mRNA levels at 24 hr post injection (P < 0.001, while the treatment with an anti-thyroid, MMI (100 ppm for 6 days significantly reduced kiss2 and gnrh1 mRNA levels (P < 0.05. gnrh2, gnrh3 and thyrotropin-releasing hormone mRNA levels were insensitive to the thyroid hormone manipulations. Furthermore, RT-PCR showed expression of thyroid hormone receptor mRNAs in laser-captured GnRH neurons but not in kiss2 neurons. This study shows that GnRH1 may be directly regulated through thyroid hormone, while the regulation of Kiss2 by T3 is more likely to be indirect.

  15. Effects of plasma total ammonia content and pH on urea excretion in Nile tilapia.

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    McKenzie, D J; Piraccini, G; Felskie, A; Romano, P; Bronzi, P; Bolis, C L

    1999-01-01

    Nile tilapia (Oreochromis niloticus) were infused with ammonium salts, acid, and base to investigate the effects of changes in arterial plasma total ammonia content (Tamm) and pH (pHa) on plasma urea-nitrogen (urea-N) levels and urea-N excretory fluxes (Jurea-N). The tilapia did not possess a functional hepatic ornithine urea-cycle (no significant carbamyl phosphate synthetase III activity). Infused substances were dissolved in a saline vehicle and injected twice (5 mL kg-1), the first infusion to "prime" the animal and promote a more marked response to the second infusion, given 2.5 h later. The results reported are those of the second infusion. Infusion of 200 mM NH4Cl increased Tamm, reduced pHa, and increased plasma urea-N and Jurea-N. Two hundred mM NH4HCO3 increased Tamm and arterial plasma total CO2 content (TaCO2), reduced pHa, and increased Jurea-N. Fifty mM HCl reduced pHa but had no effects on urea dynamics. Fifty mM NaOH increased pHa, plasma urea-N levels, and Jurea-N. Two hundred mM NaHCO3 increased pHa, TaCO2, plasma urea-N levels, and Jurea-N. Infusion of the saline vehicle was without effect. The results indicate that ammonia loading and plasma alkalosis both stimulate urea excretion in uricolytic fish. The responses to hyperammonemia or alkalosis were not modified when combined with elevated plasma bicarbonate levels.

  16. Francisella Infection in Cultured Tilapia in Thailand and the Inflammatory Cytokine Response.

    Science.gov (United States)

    Jantrakajorn, Sasibha; Wongtavatchai, Janenuj

    2016-06-01

    Francisella infections developed in freshwater Nile Tilapia Oreochromis niloticus and red tilapia Oreochromis spp. farms in Thailand during 2012-2014. The diseased fish were lethargic and pale in color and showed numerous white nodules in their enlarged spleens. Histopathological examination and electron microscopy suggested that the white nodules were multifocal granulomas consisting of coccobacilli within vacuolated cells. Isolation of Francisella-like bacteria was achieved from 42 of 100 samples, while polymerase chain reaction confirmed Francisella infections in all samples. Analysis of the 16S rRNA gene from samples obtained from three different geographical culture areas revealed more than 99% similarity with F. noatunensis subsp. orientalis. The influence of Francisella infection on inflammatory cytokines was determined on splenic cells of fish intraperitoneally injected with the bacteria (0.8 × 10(5) colony-forming units per fish). Infected tilapia showed significantly greater expression of the pro-inflammatory genes interleukin-1β (IL-1β) and tumor necrotic factor-α (TNF-α) within 24 h postinjection (hpi) and for up to 96 hpi. However, down-regulation of an anti-inflammatory gene, transforming growth factor-β (TGF-β) was observed as early as 24 hpi. This investigation demonstrates that an imbalance between pro- and anti-inflammatory cytokines in response to the infection may account for the substantial number of granulomas in fish hematopoietic tissues that was found in the later stage of the disease. Received September 9, 2015; accepted December 13, 2015.

  17. Identities among actin-encoding cDNAs of the Nile tilapia (Oreochromis niloticus and other eukaryote species revealed by nucleotide and amino acid sequence analyses

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    Andréia B. Poletto

    2008-01-01

    Full Text Available Actin-encoding cDNAs of Nile tilapia (Oreochromis niloticus were isolated by RT-PCR using total RNA samples of different tissues and further characterized by nucleotide sequencing and in silico amino acid (aa sequence analysis. Comparisons among the actin gene sequences of O. niloticus and those of other species evidenced that the isolated genes present a high similarity to other fish and other vertebrate actin genes. The highest nucleotide resemblance was observed between O. niloticus and O. mossambicus a-actin and b-actin genes. Analysis of the predicted aa sequences revealed two distinct types of cytoplasmic actins, one cardiac muscle actin type and one skeletal muscle actin type that were expressed in different tissues of Nile tilapia. The evolutionary relationships between the Nile tilapia actin genes and diverse other organisms is discussed.

  18. Molecular characterization and expression of CD2 in Nile tilapia (Oreochromis niloticus) in response to Streptococcus agalactiae stimulus.

    Science.gov (United States)

    Gan, Zhen; Wang, Bei; Tang, Jufen; Lu, Yishan; Jian, JiChang; Wu, Zaohe; Nie, Pin

    2016-03-01

    The cluster of differentiation 2 (CD2), functioning as a cell adhesion and costimulatory molecule, plays a crucial role in T-cell activation. In this paper, the CD2 gene of Nile tilapia, Oreochromis niloticus (designated as On-CD2) was cloned and its expression pattern under the stimulation of Streptococcus agalactiae was investigated. Sequence analysis showed On-CD2 protein consists of two extracellular Ig-like domains, a transmembrane region, and a long proline-rich cytoplasmic tail, which is a hallmark of CD2, and several important structural characteristics required for T-cell activation were detected in the deduced amino acid sequence of On-CD2. In healthy tilapia, the On-CD2 transcripts were mainly detected in the head kidney, spleen, blood and thymus. Moreover, there was a clear time-dependent expression pattern of On-CD2 after immunized by formalin-inactivated S. agalactiae and the expression reached the highest level at 12 h in the brain and head kidney, 48 h in the spleen, and 72 h in the thymus, respectively. This is the first report on the expression of CD2 induced by bacteria vaccination in teleosts. These findings indicated that On-CD2 may play an important role in the immune response to intracellular bacteria in Nile tilapia.

  19. Replacement of fishmeal with processed meal from knife fish Chitala ornata in diets of juvenile Nile tilapia Oreochromis niloticus

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    Sherilyn T. Abarra

    2017-02-01

    Full Text Available A 60-day feeding trial was conducted to assess the effects of processed meal from knife fish Chitala ornata (KFM as fishmeal replacement in diets of Nile tilapia Oreochromis niloticus juveniles. Five iso-nitrogenous (36.4% in dry matter and isolipidic diets (8.6% in dry matter with 0 (D1, 25 (D2, 50 (D3, 75 (D4 and 100% (D5 KFM inclusions were prepared. With a stocking density of 15 fish (0.59 ± 0.01 g per tank, tilapia juveniles were distributed randomly in fifteen 30-L tanks. Results indicate a significant increase (P  0.05 among treatments. Results of hepatic histopathology showed absence of tumors, lesions and parenchymal inflammation in all treatments. However, mild cell membrane lysis and mild and mild to moderate apoptosis were evident in liver samples. Based on the results, KFM can partially and completely replace dietary protein from fishmeal. Moreover, D4 (75% KFM is considered the optimal KFM replacement level for Nile tilapia juveniles.

  20. Oxidative stress in tissues of Nile Tilapia (Oreochromis niloticus) from a polluted site

    Energy Technology Data Exchange (ETDEWEB)

    Bainy, A.C.D. [UFSC, Florianopolis (Brazil); Carvalho, P.S.M. [CETESB, Sao Paulo (Brazil); Saito, E.; Leitao, M.A.S.; Junqueira, V.B.C. [IQUSP, Sao Paulo (Brazil)

    1995-12-31

    Pro and antioxidant parameters were compared in the erythrocytes, gill, liver and kidney of Nile Tilapia from a fish farm (Reference group) and from a polluted site at Billings Reservoir (Reservoir group). The erythrocyte oxidative stress was characterized by the increased oxygen uptake and decreased time induction (induced by t-butyl hydroperoxide, t-BHP) evidencing a higher susceptibility to oxidative damage. Moreover, a decrease in both catalase (CAT) activity and total glutathione content (GSH) in erythrocytes of Reservoir fish were observed. The higher gill cytochrome b{sub 5} levels is probably related to the enhanced oxyradical production. This fact associated to the diminished CAT and G6PDH activities establish a gill oxidative stress of Reservoir fish. The liver pro-oxidant parameters were greatly increased in the Reservoir fish. These results together with the increase in SOD activity and decrease in CAT, glutathione reductase (GR) and G6PDH activities indicate a liver oxidative stress condition. The observed increase in kidney NADH cytochrome c reductase and in both P-450 and b{sub 5} contents did not reflect in enhanced oxyradical production. The decrease in GSH observed in this tissue is probably associated to the conjugation reactions for ulterior excretion. These results furnish useful data for prospections of polluted aquatic sites in order to correlate the presence of pollutants to associated biological effects.

  1. Induction of triploidy and tetraploidy in Nile tilapia, Oreochromis niloticus (L.)

    Science.gov (United States)

    El Gamal, A.-R.A.; Davis, K.B.; Jenkins, J.A.; Les, Torrans E.

    1999-01-01

    Induction of triploidy and tetraploidy in Nile tilapia, Oreochromis niloticus, was investigated by heat shock, cold shock, hydrostatic pressure, and/ or chemicals (cytochalasin A, B, and D). Additionally, efficacy of combined protocols was determined. Heat shock 10 min after fertilization induced triploidy when incubation temperature was 24 C but not when incubation temperature was 31 C. Heat shock of 40-41 C at 4-6 min after fertilization was effective in inducing up to 100% triploidy with hatchability similar to controls. Cold shock at 13 C for 45 min five min after fertilization induced 85-100% triploids. Heat shock and multiple heat shocking were the most effective treatments for the induction of tetraploidy. Two heat treatments of 41 C applied at 65 and 80 min after fertilization for 5 min each produced approximately 80% tetraploidy in hatched fry. Immersion of fertilized eggs in cytochalasin A, B, or D at concentrations up to 10 ??g/L applied at various times and durations was ineffective in inducing triploidy or tetraploidy.

  2. Physiological and hematological responses of Nile tilapia (Oreochromis Niloticus to different anesthetics during simulated transport conditions

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    Rodrigo Diana Navarro

    2016-06-01

    Full Text Available Minimization of stress during the transportation of live fish is essential in maintaining the welfare and performance of the animals. In order to test the hypothesis that stress during transport of fingerlings of Nile tilapia (Oreochromis niloticus can be reduced with the aid of the anesthetics menthol, eugenol or benzocaine, we have assessed the effects of these agents at various concentrations on the physiological parameters and survival rates of fish subjected to conditions simulating those normally used in transportation. Fingerlings (N = 1200 were fasted for 24 hours and distributed in 20 L polyethylene bags (N = 50 per bag containing 5 L of water and an anesthetic at the appropriate concentration. Fingerlings treated with menthol at 75 mg L-1, or eugenol or benzocaine at 20 mg L-1, maintained levels of plasma cortisol and glucose that were lower than those of the stressed but untreated controls and within the physiological limits of the baseline values for this species. Under these conditions, the survival rate was 100%, suggesting that stress was substantially reduced despite dense consignment. Treatments involving higher doses of the studied agents induced significant anesthetic toxicity.

  3. Identification of (L)-fucose-binding proteins from the Nile tilapia (Oreochromis niloticus L.) serum.

    Science.gov (United States)

    Argayosa, Anacleto M; Lee, Yuan C

    2009-09-01

    Lectins are carbohydrate-binding proteins with many biological functions including cellular recognition and innate immunity. In this study, a major l-fucose-binding lectin from the serum of Nile tilapia (Oreochromis niloticus L.), designated as TFBP, was isolated by l-fucose-BSA Sepharose CL6B affinity chromatography. The SDS-PAGE (10%) analysis of TFBP revealed a major band of approximately 23 kDa with an N-terminal amino acid sequence of DQTETAGQQSXPQDIHAVLREL which did not give significant similarities to the protein databases using BLASTp searches. Ruthenium red staining indicate positive calcium-binding property of TFBP. The purified TFBP agglutinated human type O erythrocytes but not the type A and B fresh erythrocytes. Live Aeromonas hydrophila and Enterococcus faecalis cells were also agglutinated by the lectin. The fucose-binding proteins were detected in the soluble protein extracts from the gills, gut, head kidneys, liver, serum and spleen using a fucose-binding protein probe (l-fucose-BSA-horseradish peroxidase). The binding of TFBP with the l-fucose-BSA probe was inhibited by l-fucose but not by alpha-methyl-d-mannose.

  4. Kinetics of chronic inflammation in Nile tilapia fed n‑3 and n‑6 essential fatty acids

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    Róberson Sakabe

    2013-03-01

    Full Text Available The objective of this work was to investigate the effect of dietary supplementation with essential fatty acids on the kinetics of macrophage accumulation and giant cell formation in Nile tilapia (Oreochromis niloticus. The supplementation sources were soybean oil (SO, source of omega 6, n‑6 and linseed oil (LO, source of omega 3, n‑3, in the following proportions: 100% SO; 75% SO + 25% LO; 50% SO + 50% LO; 25% SO + 75% LO; and 100% LO (four replicates per treatment. After a feeding period of three months, growth performance was evaluated, and glass coverslips were implanted into the subcutaneous connective tissue of fish, being removed for examination at 2, 4, 6, and 8 days after implantation. Growth performance did not differ between treatments. Fish fed 100% linseed oil diet had the greatest macrophage accumulation and the fastest Langhans cell formation on the sixth day. On the eighth day, Langhans cells were predominant on the coverslips implanted in the fish feed 75 and 100% linseed oil. n‑3 fatty acids may contribute to macrophage recruitment and giant cell formation in fish chronic inflammatory response to foreign body.

  5. Integrated cytogenetics and genomics analysis of transposable elements in the Nile tilapia, Oreochromis niloticus.

    Science.gov (United States)

    Valente, Guilherme; Kocher, Thomas; Eickbush, Thomas; Simões, Rafael P; Martins, Cesar

    2016-06-01

    Integration of cytogenetics and genomics has become essential to a better view of architecture and function of genomes. Although the advances on genomic sequencing have contributed to study genes and genomes, the repetitive DNA fraction of the genome is still enigmatic and poorly understood. Among repeated DNAs, transposable elements (TEs) are major components of eukaryotic chromatin and their investigation has been hindered even after the availability of whole sequenced genomes. The cytogenetic mapping of TEs in chromosomes has proved to be of high value to integrate information from the micro level of nucleotide sequence to a cytological view of chromosomes. Different TEs have been cytogenetically mapped in cichlids; however, neither details about their genomic arrangement nor appropriated copy number are well defined by these approaches. The current study integrates TEs distribution in Nile tilapia Oreochromis niloticus genome based on cytogenetic and genomics/bioinformatics approach. The results showed that some elements are not randomly distributed and that some are genomic dependent on each other. Moreover, we found extensive overlap between genomics and cytogenetics data and that tandem duplication may be the major mechanism responsible for the genomic dynamics of TEs here analyzed. This paper provides insights in the genomic organization of TEs under an integrated view based on cytogenetics and genomics.

  6. Effects of diazinon on the lymphocytic cholinergic system of Nile tilapia fish (Oreochromis niloticus).

    Science.gov (United States)

    Toledo-Ibarra, G A; Díaz-Resendiz, K J G; Pavón-Romero, L; Rojas-García, A E; Medina-Díaz, I M; Girón-Pérez, M I

    2016-08-01

    Fish rearing under intensive farming conditions can be easily disturbed by pesticides, substances that have immunotoxic properties and may predispose to infections. Organophosphorus pesticides (OPs) are widely used in agricultural activities; however, the mechanism of immunotoxicity of these substances is unclear. The aim of this study was to evaluate the effect of diazinon pesticides (OPs) on the cholinergic system of immune cells as a possible target of OP immunotoxicity. We evaluated ACh levels and cholinergic (nicotinic and muscarinic) receptor concentration. Additionally, AChE activity was evaluated in mononuclear cells of Nile tilapia (Oreochromis niloticus), a freshwater fish mostly cultivated in tropical regions around the world. The obtained results indicate that acute exposure to diazinon induces an increase in ACh concentration and a decrease in nAChR and mAChR concentrations and AChE activity in fish immune cells, This suggests that the non-neuronal lymphocytic cholinergic system may be the main target in the mechanism of OP immunotoxicity. This study contributes to the understanding of the mechanisms of immunotoxicity of pollutants and may help to take actions for animal health improvement.

  7. Nutritional background changes the hypolipidemic effects of fenofibrate in Nile tilapia (Oreochromis niloticus)

    Science.gov (United States)

    Ning, Li-Jun; He, An-Yuan; Lu, Dong-Liang; Li, Jia-Min; Qiao, Fang; Li, Dong-Liang; Zhang, Mei-Ling; Chen, Li-Qiao; Du, Zhen-Yu

    2017-01-01

    Peroxisome proliferation activated receptor α (PPARα) is an important transcriptional regulator of lipid metabolism and is activated by high-fat diet (HFD) and fibrates in mammals. However, whether nutritional background affects PPARα activation and the hypolipidemic effects of PPARα ligands have not been investigated in fish. In the present two-phase study of Nile tilapia (Oreochromis niloticus), fish were first fed a HFD (13% fat) or low-fat diet (LFD; 1% fat) diet for 10 weeks, and then fish from the first phase were fed the HFD or LFD supplemented with 200 mg/kg body weight fenofibrate for 4 weeks. The results indicated that the HFD did not activate PPARα or other lipid catabolism-related genes. Hepatic fatty acid β-oxidation increased significantly in the HFD and LFD groups after the fenofibrate treatment, when exogenous substrates were sufficiently provided. Only in the HFD group, fenofibrate significantly increased hepatic PPARα mRNA and protein expression, and decreased liver and plasma triglyceride concentrations. This is the first study to show that body fat deposition and dietary lipid content affects PPARα activation and the hypolipidemic effects of fenofibrate in fish, and this could be due to differences in substrate availability for lipid catabolism in fish fed with different diets. PMID:28139735

  8. Assessment of benthic macroinvertebrates at Nile tilapia production using artificial substrate samplers

    Directory of Open Access Journals (Sweden)

    M. S. G. Moura e Silva

    Full Text Available Abstract Biomonitoring is a cheap and effective tool for evaluation of water quality, and infer on the balance of aquatic ecosystems. The benthic macroinvertebrates are bioindicators sensitive to environmental changes, and can assist in detecting and preventing impacts such as organic enrichment and imbalance in the food chain. We compared the structure of benthic communities on artificial substrate samplers located in places near and far from net cages for production of Nile tilapia (Oreochromis niloticus. Samplers were manufactured with nylon net, using substrates such as crushed stone, gravel, loofah and cattail leaves. Samples were collected after 30 days of colonization, rinsed and then the specimens were identified and quantified. The following metrics were calculated: richness of Operational Taxonomic Units, Margalef richness, abundance of individuals, Shannon index and evenness index. The macrobenthic community structure was strongly modified according to the proximity of the net cages. Metrics showed significant differences (p < 0.05 between near and distant sites, for both periods (dry and rainy seasons. The position of the samplers significantly affected the structure of macroinvertebrate community, as near sites showed higher values for the community metrics, such as richness and diversity. Near sites presented a larger number of individuals, observed both in the dry and rainy seasons, with a predominance of Chironomidae (Diptera in the dry season and Tubificidae (Oligochaeta in the rainy season.

  9. Growth, immune status and intestinal morphology of Nile tilapia fed dietary prebiotics (mannan oligosaccharides-MOS

    Directory of Open Access Journals (Sweden)

    Ricardo Yuji-Sado

    2015-11-01

    Full Text Available Farmers must conform to Best Management Practices in fish production such as the development of non-antibiotic dietary supplements for fish growth and health management. We determined the effects of increasing levels of dietary mannan oligosaccharides on growth, immune system and intestine integrity of Nile tilapia. Fish (49.6 ± 10.8 g were randomly distributed into 12 tanks (250 L; 20 fish per tank and fed during 60 days with a practical diet supplemented with 0.0, 0.2, 0.4 and 0.6% dietary mannan oligosaccharides (n = 3. Fish growth and immune system were not affected (P > 0.05 by treatments. Fish fed 0.4% prebiotic supplementation presented increased (P < 0.05 intestinal fold height. Moreover, the intestine muscular layer thickness was increased in fish fed 0.4 and 0.6% dietary prebiotic. After 60 days, there were no effects on intestinal morphology. Studies regarding characterization of intestinal microbiota and experiment that reproduce commercial fish production systems hearing conditions are necessary to determine the effective use of this dietary supplement for the species.

  10. Polycyclic Aromatic Hydrocarbon Contamination in Nile Tilapia (Oreochromis Niloticus : Analysis in Liver and Bile

    Directory of Open Access Journals (Sweden)

    Voravit Cheevaporn

    2010-07-01

    Full Text Available Polycyclic aromatic hydrocarbons (PAHs, mainly from petroleum products, are a source of worldwide contamination, and it is in the present study, we exposed Nile Tilapia in aquaria to No-Observed-Effect-Levels (NOELs of naphthalene, phenanthrene and pyrene for periods up to 9 days in a continuous flow system. Additional studies were carried out on fish exposed to lubricating oil, gasoline and diesel oil. Two methods were used to measure the levels of these PAHs: determination of ethoxyresorufin-O-deethylase (EROD activity in liver extracts, and fixed wavelength fluorescence (FF of PAH in bile. Optimal excitation wavelengths for FF analyses were determined to 290, 260 and 341 nm for naphthalene, phenanthrene and pyrene, respectively. The optimal emission wavelengths were 335, 380 and 383 nm, respectively. EROD activity and fluorescence intensity increased with increasing PAH concentrations and increasing exposure times. Similar results were obtained after exposure to lubricating oil, gasoline, or diesel oil. There was a high and significant correlation between the two methods. In view of its higher accuracy, lower cost, and convenience FF offered better possibilities than EROD determination to monitor PAH contamination in fish.

  11. Use of tuna industry waste in diets for Nile tilapia, Oreochromis niloticus, fingerlings: effect on digestibility and growth performance

    Directory of Open Access Journals (Sweden)

    Crisantema Hernández

    2013-07-01

    Full Text Available During the tuna canning process, about 52~54% of the total weight of the fish is discarded as waste, which can be processed in order to obtain tuna byproducts meal (TBM, or stabilized as tuna silage hydrolysates (TSH. Both products were tested as replacements of soybean meal (SBM, in diets for fingerling male Nile tilapia Oreochromis niloticus. Seven test diets were isonitrogenous (35% CP and isoenergetic (19 kJ g-1: a basal diet contained SBM as main protein source (TSH0; four experimental diets had increasing inclusion levels of TSH replacing 25, 50, 75 and 100% of the SBM protein. The sixth diet contained TBM as sole protein source, and a commercial feed for tilapia was used as reference diet (RD. The diets were fed for eight weeks to triplicate tanks, each with 15 fry tilapia (initial weight of 0.89 ± 0.29 g. Tilapia fed the TBM diet had greater weight gain and feed intake, and lower feed conversion ratios than those fed diets containing with TSH. The RD, TSH25 and TSH50 diets gave the similar growth response. Fish fed diets TSH0, TSH75% and TSH100% showed reduced growth performance.

  12. The potential effects of Spirulina platensis (Arthrospira platensis on tissue protection of Nile tilapia (Oreochromis niloticus through estimation of P53 level

    Directory of Open Access Journals (Sweden)

    Mai D. Ibrahem

    2014-01-01

    Full Text Available The current study was designed to investigate the potential effect of Spirulina platensis, Arthrospira platensis, (SP on tissue protection of Nile tilapia (Oreochromis niloticus through estimation of P53 level. Five isonitrogenous and isocaloric rations containing graded levels of dried SP 5, 7.5,10, 15, and 20 g/kg diet were fed separately to five equal groups of O. niloticus fingerlings, additional control group was assigned for 3 months. Liver samples were separately collected from each group by the end of each month. The expression level of P53 showed a substantial decrease among the treated groups in a time-dependent manner. It is therefore advisable to incorporate SP in diets for tissue protection and antioxidant effects in cultured O. niloticus.

  13. The potential effects of Spirulina platensis (Arthrospira platensis) on tissue protection of Nile tilapia (Oreochromis niloticus) through estimation of P53 level

    Science.gov (United States)

    Ibrahem, Mai D.; Ibrahim, Marwa A.

    2013-01-01

    The current study was designed to investigate the potential effect of Spirulina platensis, Arthrospira platensis, (SP) on tissue protection of Nile tilapia (Oreochromis niloticus) through estimation of P53 level. Five isonitrogenous and isocaloric rations containing graded levels of dried SP 5, 7.5,10, 15, and 20 g/kg diet were fed separately to five equal groups of O. niloticus fingerlings, additional control group was assigned for 3 months. Liver samples were separately collected from each group by the end of each month. The expression level of P53 showed a substantial decrease among the treated groups in a time-dependent manner. It is therefore advisable to incorporate SP in diets for tissue protection and antioxidant effects in cultured O. niloticus. PMID:25685480

  14. Innate immune defenses exhibit circadian rhythmicity and differential temporal sensitivity to a bacterial endotoxin in Nile tilapia (Oreochromis niloticus)

    DEFF Research Database (Denmark)

    Lazado, Carlo Cabacang; Skov, Peter Vilhelm; Pedersen, Per Bovbjerg

    2016-01-01

    exposed at ZT15. Taken together, this study shows that several key components of humoral immunity in tilapia exhibit circadian rhythms and adapt to photoperiodic changes. Further, results of the bacterial endotoxin challenge suggest that responsiveness of serum humoral factors to a biological insult......The present study investigated the daily dynamics of humoral immune defenses and the temporal influence in the sensitivity of these responses to a bacterial endotoxin in Nile tilapia (Oreochromis niloticus). The first experiment subjected the fish to two photoperiod conditions, 12L:12D (LD) and 0L......:24D (DD), for 20 days to characterize the rhythms of humoral immunity. Serum alkaline phosphatase (ALP), lysozyme (LYZ), peroxidase (PER) and protease (PRO) exhibited significant rhythmicity under LD but not in DD. No significant rhythms were observed in esterase (ESA) and anti-protease (ANTI...

  15. Physiological, biochemical and histometric responses of Nile tilapia (Oreochromis niloticus L.) by dietary organic chromium (chromium picolinate) supplementation

    OpenAIRE

    2014-01-01

    Chromium has been recognized as a new and important micro-nutrient, essential for both human and animal nutrition. This study was conducted to evaluate the appropriateness and/or the use of safety level of dietary chromium picolinate (Cr-Pic), and its effects on the physiological responses, the histometric characteristics, and the chemical analysis of dorsal muscles of mono-sex Nile tilapia, Oreochromis niloticus. A total of 420 fingerlings (28.00 ± 0.96 g) were randomly distributed into 21 f...

  16. Construction of a Streptococcus iniae sortase A mutant and evaluation of its potential as an attenuated modified live vaccine in Nile tilapia (Oreochromis niloticus).

    Science.gov (United States)

    Wang, J; Zou, L L; Li, A X

    2014-10-01

    Streptococcus iniae is a major Gram-positive aquatic pathogen, which causes invasive diseases in cultured fish worldwide. The identification of potential virulence determinants of streptococcal infections will help to understand and control this disease, but only a few have been confirmed in S. iniae. Sortase A (srtA) is the key enzyme that anchors pre-mature cell wall-attached proteins to peptidoglycan and it can affect the correct positioning of surface proteins, as well as the course of Gram-positive bacterial infection, thereby making it a potential target in the study of virulence factors and disease control. In this study, the 759 bp srtA gene was cloned from pathogenic S. iniae TBY-1 strain and the mutant strain TBY-1ΔsrtA was constructed via allelic exchange mutagenesis. We found that srtA shares high similarities with sortase A from other Streptococcus spp. Direct survival rate assay and challenge experiments were performed, which showed that the mutant strain TBY-1ΔsrtA had a lower survival capacity in healthy tilapia blood and it was less virulent than the wild type strain in tilapia, thereby indicating that the deletion of sortase A affects the virulence and infectious capacity of S. iniae. The mutant strain TBY-1ΔsrtA was used as a live vaccine, which was administered via intraperitoneal injection, and it provided the relative percent survival value of 95.5% in Nile tilapia, thereby demonstrating its high potential as an effective attenuated live vaccine candidate.

  17. Effects of dietary levels of vitamin A on growth, hematology, immune response and resistance of Nile tilapia (Oreochromis niloticus) to Streptococcus iniae

    Science.gov (United States)

    This study was conducted to evaluate the effect of supplemental levels of vitamin A (0, 2,500, 5,000, 10,000, and 20,000 IU/kg diet) on the growth performance, hematology, immune response and resistance of Nile tilapia, Oreochromis niloticus to Streptococcus iniae challenge. Each diet was fed to Nil...

  18. The effect of NovaSil dietary supplementation on the growth and health performance of Nile tilapia (Oreochromis niloticus) fed aflatoxin-B1 contaminated feed

    Science.gov (United States)

    The objective of this study was to evaluate the ability of NovaSil (NS) clay to sorb and mitigate the toxic effects of aflatoxin B1 (AFB1) in Nile tilapia (Oreochromis niloticus). Growth performance, specific innate immunological function, intestinal microbial community, and histology were evaluate...

  19. Phenotype and genetic parameters for body measurements, reproductive traits and gut lenght of Nile tilapia (Oreochromis niloticus) selected for growth in low-input earthen ponds

    NARCIS (Netherlands)

    Charo-Karisa, H.; Bovenhuis, H.; Rezk, M.A.; Ponzoni, R.W.; Arendonk, van J.A.M.; Komen, J.

    2007-01-01

    In this study we present estimates of phenotypic and genetic parameters for body size measurements, reproductive traits, and gut length for Nile tilapia (Oreochromis niloticus) selected for growth in fertilized earthen ponds for two generations. Throughout the experiment, ponds were fertilized daily

  20. Growth performance and resistance to Streptococcus iniae of juvenile Nile tilapia (Oreochromis niloticus) fed diets supplemented with GroBiotic - A and Brewtech Dried Brewers Yeast

    Science.gov (United States)

    This study was conducted to evaluate the effect of dietary levels of Brewtech® dried brewers yeast (BY) and GroBiotic®-A (GB) on growth performance, proximate body composition, immune response and resistance of juvenile Nile tilapia to Streptococcus iniae challenge. A practical basal (control) diet ...

  1. Evaluation of plant and animal protein sources as partial or total replacement of fish meal in diets for juvenile Nile tilapia

    Science.gov (United States)

    A feeding trial was conducted in a closed system with Nile tilapia (Oreochromis niloticus) juveniles (mean weight, 2.84 g) to examine the effects of total replacement of fish meal (FM), with and without supplementation of DL-methionine (Met) and L-lysine (Lys), by plant protein sources. Fish were f...

  2. Cloning and molecular characterization of complement component 1 inhibitor (C1INH) and complement component 8β (C8β) in Nile tilapia (Oreochromis niloticus).

    Science.gov (United States)

    He, Anyuan; Yang, Jie; Tang, Shoujie; Wang, Chenghui

    2013-09-01

    Nile tilapia (Oreochromis niloticus), one of the most important groups of food fishes in the world, has frequently suffered from serious challenge from pathogens in recent years. Immune responses of Nile tilapia should be understood to protect the aquaculture industry of this fish. The complement system has an important function in recognizing bacteria, opsonizing these pathogens by phagocytes, or killing them by direct lysis. In this study, two Nile tilapia complement component genes, complement component 1 inhibitor (C1INH) and complement component 8β subunit (C8β), were cloned and their expression characteristics were analyzed. C1INH cDNA was found containing a 1791 bp open reading frame (ORF) encoding a putative protein with 597 amino acids, a 101 bp 5'-untranslated region (UTR) and a 236 bp 3'-UTR. The predicted protein structure for this gene consisted of two Ig-like domains and glycosyl hydrolase family-9 active site signature 2. The C8β cDNA consisted of a 1761 bp ORF encoding 587 amino acids, a 15 bp 5'-UTR and a 170 bp 3'-UTR. The predicted protein of C8β contained three motifs, thrombospondin type-1 repeat, membrane attack complex/perforin domain, and LDL-receptor class A. Expression analysis revealed that these two complement genes were highly expressed in the liver, however, were weakly expressed in the gill, heart, brain, kidney, intestine, spleen and dorsal muscle tissues. The present study provided insights into the complement system and immune functions of Nile tilapia.

  3. Draft Genome Sequence of Francisella noatunensis subsp. orientalis STIR-GUS-F2f7, a Highly Virulent Strain Recovered from Diseased Red Nile Tilapia Farmed in Europe

    Science.gov (United States)

    Larsson, Pär; Wehner, Stefanie; Bekaert, Michaël; Öhrman, Caroline; Metselaar, Matthijs; Thompson, Kimberly Dawn; Richards, Randolph Harvey; Penman, David James; Adams, Alexandra

    2017-01-01

    ABSTRACT A highly virulent strain of Francisella noatunensis subsp. orientalis, STIR-GUS-F2f7, was isolated from moribund red Nile tilapia (Oreochromis niloticus) farmed in Europe. In this communication, the complete genome sequencing of this bacterium is reported. PMID:28302784

  4. Complete Genome Sequence of Streptococcus iniae UEL-Si1, Isolated in Diseased Nile Tilapia (Oreochromis niloticus) from Northern Paraná, Southern Brazil

    Science.gov (United States)

    Gonçalves, Kátia B.; Scarpassa, Josiane A.; Pretto-Giordano, Lucienne G.

    2017-01-01

    ABSTRACT The Streptococcus iniae UEL-Si1 strain was isolated from diseased Nile tilapia within the Paranapanema River Basin, Northern Paraná, Brazil. This is an emerging infectious disease agent of fish from Brazil, and sequencing of the complete genome is fundamental to understanding aspects relative to pathogenesis, infection, epidemiology, and immunity. PMID:28082497

  5. Use of biofuel by-product from the green algae Desmochloris sp. and diatom Nanofrustulum sp. meal in diets for nile tilapia Oreochromis niloticus

    Science.gov (United States)

    Algal by-product meals from the Hawaiian biofuels industry were evaluated as protein ingredients in diets for juveniles of Nile tilapia (Oreochromis niloticus). Four experimental diets were formulated to contain 40% protein and were made with fish meal, soybean meal, whole diatom (Nanofrustulum sp.)...

  6. Ecological niche modeling of the invasive potential of Nile tilapia Oreochromis niloticus in African river systems: concerns and implications for the conservation of indigenous congenerics

    CSIR Research Space (South Africa)

    Zengeya, TA

    2013-07-01

    Full Text Available of species range (native vs. introduced) on model performance and assessed whether or not there is evidence suggestive of a niche shift in Nile tilapia following its introduction. Niche models were constructed using Maxent and the degree of niche similarity...

  7. The effect of type of carbohydrate (starch vs. nonstarch polysaccharides) on nutrients digestibility, energy retention and maintenance requirements in Nile tilapia

    NARCIS (Netherlands)

    Haidar, Mahmoud N.; Petie, Mischa; Heinsbroek, Leon T.N.; Verreth, Johan A.J.; Schrama, Johan W.

    2016-01-01

    For Nile tilapia, the energetic value of non-starch polysaccharides (NSP) was compared to starch. It was assessed if carbohydrate type (NSP vs. starch) affected the energetic utilization for growth (KgDE) and the energy requirements for maintenance (DEm). Eighteen groups of fish were assigned in 2 ×

  8. Haploinsufficiency of SF-1 Causes Female to Male Sex Reversal in Nile Tilapia, Oreochromis niloticus.

    Science.gov (United States)

    Xie, Qing-Ping; He, Xue; Sui, Yi-Ning; Chen, Li-Li; Sun, Li-Na; Wang, De-Shou

    2016-06-01

    Steroidogenic factor-1 (Sf-1) (officially designated nuclear receptor subfamily 5 group A member 1 [NR5A1]) is a master regulator of steroidogenesis and reproduction in mammals. However, its function remains unclear in nonmammalian vertebrates. In the present study, we used immunohistochemistry to detect expression of Sf-1 in the steroidogenic cells, the interstitial, granulosa, and theca cells of the ovary, and the Leydig cells of the testis, in Nile tilapia. Clustered regularly interspaced short palindromic repeats/CRISPR associated protein 9 (Cas9) cleavage of sf-1 resulted in a high mutation rate in the F0 generation and a phenotype of gonadal dysgenesis and reduced steroidogenic cells in XX and XY fish. Sf-1 deficiency also resulted in decreased cytochrome P450, family 19, subfamily A, polypeptide 1a, forkhead box L2 expression, and serum estradiol-17β in XX fish. In XY fish, Sf-1 deficiency increased cytochrome P450, family 19, subfamily A, polypeptide 1a and forkhead box L2 expression but decreased cytochrome P450, family 11, subfamily B, polypeptide 2 expression and serum 11-ketotestosterone levels. 17α-methyltestosterone treatment successfully rescued the gonadal phenotype of Sf-1-deficient XY fish, as demonstrated by normal spermatogenesis and production of F1 mutants. In contrast, estradiol-17β treatment only partially rescued the gonadal phenotype of Sf-1-deficient XX fish, as demonstrated by the appearance of phase II oocytes. Furthermore, both sf-1(+/-) F1 XX and XY mutants developed as fertile males, although spermatogenesis was delayed and efferent duct formation was disordered. Our data suggest that Sf-1 is a major regulator of steroidogenesis and reproduction in fish, as it is in mammals. Sf-1 deficiency resulted in gonadal dysgenesis and feminization of XY gonads. However, unlike in mammals, Sf-1 deficiency also resulted in female to male sex reversal in 8.1% of F0 and 92.1% of sf-1(+/-) F1 in XX fish.

  9. PHARMACOKINETIC EVALUATION OF MELOXICAM AFTER INTRAVENOUS AND INTRAMUSCULAR ADMINISTRATION IN NILE TILAPIA (OREOCHROMIS NILOTICUS).

    Science.gov (United States)

    Fredholm, Daniel V; Mylniczenko, Natalie D; KuKanich, Butch

    2016-09-01

    Critically evaluating the pharmacokinetic behavior of a drug in the body provides crucial information about how to effectively treat a patient. Pharmacokinetic studies that exist in fish have primarily focused on drugs used to treat infectious disease, with minimal attention given to analgesic drugs. The objective of this study was to determine the pharmacokinetics of meloxicam (1 mg/kg) in Nile tilapia ( Oreochromis niloticus ) (n = 12). A single dose of meloxicam was administered either i.v. or i.m. Blood samples were obtained at predetermined times after drug injection. Plasma meloxicam concentrations were determined by a validated liquid chromatography/mass spectrometry method, and noncompartmental pharmacokinetic analysis was performed. The mean peak plasma concentration after i.m. injection was 1.95 μg/ml. The mean terminal half-life of meloxicam after i.v. and i.m. administration was 1.36 and 1.8 hr, respectively. The area under the plasma concentration-versus-time curve extrapolated to infinity was 11.26 hr·μg/ml after i.v. administration and 5.72 hr·μg/ml after i.m. administration. Bioavailability of meloxicam after i.m. administration was approximately half that of i.v. administration. Elimination was rapid in both the i.m. and i.v. routes of administration, suggesting that maintaining clinically relevant plasma concentrations may be difficult using this dose. This study represents the first pharmacokinetic evaluation of a nonsteroidal anti-inflammatory drug in a fish species, and further studies evaluating efficacy are needed.

  10. Evaluation of tamoxifen citrate efficiency on sexual inversion of Nile tilapia (Oreochromis niloticus

    Directory of Open Access Journals (Sweden)

    Marco Antonio Zanoni

    2014-09-01

    Full Text Available The experiment was conducted to evaluate the influence of tamoxifen on sexual inversion of Nile tilapia larvae from two days of life, the experimental desing was compounded of five treatments and three replicates, and fish were fed diets with different amounts of tamoxifen: 0, 25, 50, 75 and 100 mg kg-1 of feed. After 28 days of treatment, larvae were counted and transferred to water tanks of 500 liters and then which were fed with a diet containing 28% crude protein for more 60 days. After this period the fry were sexed by the “squash”. The survival 75.5 ± 5.74, 73 ± 4.76, 66 ± 11.19, 76.5 ± 4.12, 75 ± 3.46 and average percentage of male individuals 62.5 ± 5, 70 ± 8.1, 60 ± 8.2, 70 ± 0.0, 62.5 ± 9.5 for treatments 0, 25, 50, 75 and 100 mg of tamoxifenkg-1 diet, respectively, showed no statistically significant differences (p<0,05. The number of gonads in each fish experienced a significant reduction in the treatments with 75 and 100 mg of tamoxifen (89.3 and 79.3 ± 0.527 ± 0.378 when compared with treatments 0, 25 and 50 mg of tamoxifen (98, 9 ± 1.0, 97.6 ± 1.0 and 94.5 ± 1.0, respectively, the histological structure of female gonads did not differ and ovaries in all treatments showed well-defined and oocytes at several stages of maturation.

  11. Nile tilapia skin collagen sponge modified with chemical cross-linkers as a biomedical hemostatic material.

    Science.gov (United States)

    Sun, Leilei; Li, Bafang; Jiang, Dandan; Hou, Hu

    2017-07-26

    Nile tilapia skin collagen sponges were fabricated by freeze-drying technology and modified with 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide in the presence of N-hydroxysuccinimide (EDC/NHS), genipin+PBS, genipin+ethanol, tea polyphenol (TP), nordihydroguaiaretic acid (NDGA) and diphenyl phosphoryl azide (DPPA). Physicochemical and biological properties, micromorphology and compatibility before and after modification were investigated to evaluate collagen sponge as a hemostatic biomedical material. The mechanical property of collagen sponges strengthened after cross-linking. The elongation at break of cross-linked collagen sponges decreased except for EDC/NHS, which was close to that of non-crosslinked. The collagen sponge cross-linked with EDC/NHS exhibited the highest hygroscopicity in comparison with other cross-linkers. The resistance to collagenase biodegradation of collagen sponges after cross-linking strengthened significantly except for NDGA. Collagen sponges cross-linked with EDC/NHS, TP and NDGA maintained high porosity (97-98%), similar to non-crosslinked (98.42%). Collagen sponges could shorten the blood coagulation time. From the variations of the FTIR spectrum pattern and SEM, DPPA could change the secondary structure of collagen and destroy the spongy structure of collagen sponge, which was not suitable for the cross-linking of collagen sponge. Whereas, EDC/NHS was recognized as a perfect cross-linker owing to its excellent properties and porous microstructure. All fabricated collagen sponges were recognized to be biocompatible by the hemolysis assay in vitro. Therefore, collagen sponge modified with EDC/NHS could be used as a perfect biomedical hemostatic material. Copyright © 2017 Elsevier B.V. All rights reserved.

  12. Towards Sustainable Aquafeeds: Complete Substitution of Fish Oil with Marine Microalga Schizochytrium sp. Improves Growth and Fatty Acid Deposition in Juvenile Nile Tilapia (Oreochromis niloticus)

    Science.gov (United States)

    Sarker, Pallab K.; Kapuscinski, Anne R.; Lanois, Alison J.; Livesey, Erin D.; Bernhard, Katie P.; Coley, Mariah L.

    2016-01-01

    We conducted a 84-day nutritional feeding experiment with dried whole cells of DHA-rich marine microalga Schizochytrium sp. (Sc) to determine the optimum level of fish-oil substitution (partial or complete) for maximum growth of Nile tilapia. When we fully replaced fish oil with Schizochytrium (Sc100 diet), we found significantly higher weight gain and protein efficiency ratio (PER), and lower (improved) feed conversion ratio (FCR) and feed intake compared to a control diet containing fish oil (Sc0); and no significant change in SGR and survival rate among all diets. The Sc100 diet had the highest contents of 22:6n3 DHA, led to the highest DHA content in fillets, and consequently led to the highest DHA:EPA ratios in tilapia fillets. Schizochytrium sp. is a high quality candidate for complete substitution of fish oil in juvenile Nile tilapia feeds, providing an innovative means to formulate and optimize the composition of tilapia juvenile feed while simultaneously raising feed efficiency of tilapia aquaculture and to further develop environmentally and socially sustainable aquafeeds. Results show that replacing fish oil with DHA-rich marine Sc improves the deposition of n3 LC PUFA levels in tilapia fillet. These results support further studies to lower Schizochytrium production costs and to combine different marine microalgae to replace fish oil and fishmeal into aquafeeds. PMID:27258552

  13. Towards Sustainable Aquafeeds: Complete Substitution of Fish Oil with Marine Microalga Schizochytrium sp. Improves Growth and Fatty Acid Deposition in Juvenile Nile Tilapia (Oreochromis niloticus).

    Science.gov (United States)

    Sarker, Pallab K; Kapuscinski, Anne R; Lanois, Alison J; Livesey, Erin D; Bernhard, Katie P; Coley, Mariah L

    2016-01-01

    We conducted a 84-day nutritional feeding experiment with dried whole cells of DHA-rich marine microalga Schizochytrium sp. (Sc) to determine the optimum level of fish-oil substitution (partial or complete) for maximum growth of Nile tilapia. When we fully replaced fish oil with Schizochytrium (Sc100 diet), we found significantly higher weight gain and protein efficiency ratio (PER), and lower (improved) feed conversion ratio (FCR) and feed intake compared to a control diet containing fish oil (Sc0); and no significant change in SGR and survival rate among all diets. The Sc100 diet had the highest contents of 22:6n3 DHA, led to the highest DHA content in fillets, and consequently led to the highest DHA:EPA ratios in tilapia fillets. Schizochytrium sp. is a high quality candidate for complete substitution of fish oil in juvenile Nile tilapia feeds, providing an innovative means to formulate and optimize the composition of tilapia juvenile feed while simultaneously raising feed efficiency of tilapia aquaculture and to further develop environmentally and socially sustainable aquafeeds. Results show that replacing fish oil with DHA-rich marine Sc improves the deposition of n3 LC PUFA levels in tilapia fillet. These results support further studies to lower Schizochytrium production costs and to combine different marine microalgae to replace fish oil and fishmeal into aquafeeds.

  14. Towards Sustainable Aquafeeds: Complete Substitution of Fish Oil with Marine Microalga Schizochytrium sp. Improves Growth and Fatty Acid Deposition in Juvenile Nile Tilapia (Oreochromis niloticus.

    Directory of Open Access Journals (Sweden)

    Pallab K Sarker

    Full Text Available We conducted a 84-day nutritional feeding experiment with dried whole cells of DHA-rich marine microalga Schizochytrium sp. (Sc to determine the optimum level of fish-oil substitution (partial or complete for maximum growth of Nile tilapia. When we fully replaced fish oil with Schizochytrium (Sc100 diet, we found significantly higher weight gain and protein efficiency ratio (PER, and lower (improved feed conversion ratio (FCR and feed intake compared to a control diet containing fish oil (Sc0; and no significant change in SGR and survival rate among all diets. The Sc100 diet had the highest contents of 22:6n3 DHA, led to the highest DHA content in fillets, and consequently led to the highest DHA:EPA ratios in tilapia fillets. Schizochytrium sp. is a high quality candidate for complete substitution of fish oil in juvenile Nile tilapia feeds, providing an innovative means to formulate and optimize the composition of tilapia juvenile feed while simultaneously raising feed efficiency of tilapia aquaculture and to further develop environmentally and socially sustainable aquafeeds. Results show that replacing fish oil with DHA-rich marine Sc improves the deposition of n3 LC PUFA levels in tilapia fillet. These results support further studies to lower Schizochytrium production costs and to combine different marine microalgae to replace fish oil and fishmeal into aquafeeds.

  15. Ecological Risk Assessment of Metal Pollution along Greater Cairo Sector of the River Nile, Egypt, Using Nile Tilapia, Oreochromis niloticus, as Bioindicator

    Directory of Open Access Journals (Sweden)

    Wael A. Omar

    2015-01-01

    Full Text Available The present work aims to evaluate seasonal metal pollution along Greater Cairo sector of the River Nile, Egypt, using wild Nile tilapia, Oreochromis niloticus, as bioindicator and to conduct a risk assessment for human consumers. Greater Cairo is the largest populated area along the whole course of River Nile with a wide range of anthropogenic activities. Effects of metal pollution on fish body indices were studied using condition factor (CF and scaled mass index (SMI. Metal pollution index (MPI showed that the total metal load in fish organs followed the follwoing order: kidney > liver > gill > muscle which gives a better idea about the target organs for metal accumulation. Metal concentrations in fish muscle (edible tissue showed the following arrangement: Fe > Zn > Cu > Mn > Pb > Cd. Metal’s bioaccumulation factor (BAF in fish muscle showed the following arrangement: Zn > Cu > Fe > Mn > Cd and Pb. The hazard index (HI as an indicator of human health risks associated with fish consumption showed that adverse health effects are not expected to occur in most cases. However, the metals’ cumulative risk effects gave an alarming sign specifically at high fish consumption rates.

  16. Carboxymethyl chitosan modulates the genotoxic risk and oxidative stress of perfluorooctanoic acid in Nile tilapia (Oreochromis niloticus

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    Fagr Kh. Abdel-Gawad

    2016-01-01

    Full Text Available Perfluorooctanoic acid (PFOA is one of the most commonly used perfluorinated compounds. Being a persistent environmental pollutant, it can accumulate in human tissues via various exposure routes. The aim of the current study was to evaluate the protective role of carboxymethyl chitosan (CMC against PFOA-induced toxicity at the genetic and protein levels in Nile tilapia using the biochemistry analysis, SDS–PAGE electrophoresis, comet assay and RFLP–PCR methods. The results indicated that exposure to PFOA in water (30 mg/L for 30 days resulted in a significant increase in ALT, AST, BUN, creatinine accompanied with a significant decrease in total protein and albumin. PFOA also increased DNA damage in electrophoresis condition and induced DNA and protein polymorphic band in comparison to control fish. CMC alone at 1% and 2% (W/W in fish diets did not induce any alterations in the biochemical parameters, DNA or protein levels compared to the control group. Furthermore, CMC succeeded to decrease the toxicity of PFOA in a dose dependent manner. It could be concluded that PFOA induced genotoxicity and oxidative stress in fish similar to those reported in mammals. CMC is a promising candidate and has a protective effect against-PFOA induced in vivo DNA damage and protein alteration in Nile tilapia. This effect might be attributable to its ability to decrease intracellular ROS and its antioxidant properties.

  17. DNA methylation of pituitary growth hormone is involved in male growth superiority of Nile tilapia (Oreochromis niloticus).

    Science.gov (United States)

    Zhong, Huan; Xiao, Jun; Chen, Wenzhi; Zhou, Yi; Tang, Zhanyang; Guo, Zhongbao; Luo, Yongju; Lin, Zhengbao; Gan, Xi; Zhang, Ming

    2014-05-01

    Growth hormone (GH) and its receptors are critical regulators of somatic growth and metabolism. It has been shown in mammals that the methylation of cytosines within the GH promoter plays a key role in regulating transcripts expression. In the present study, the GH, GHR1 and GHR2 proximal promoters were identified and the methylation levels of these genes in corresponding tissues were assayed. The results suggested that significant arising of GH putative promoter methylation levels in pituitary was observed in females compared with males. However, no such sex-specific changes were found in GHR1 and GHR2 promoters. The GH mRNA expression also was influenced by GH promoter methylation levels in pituitary, which resulted in the higher growth rate of Nile tilapia males. Meanwhile, the methylation levels of GH putative promoter were negatively correlated with growth rate as well as mRNA expression of GH. Furthermore, the methylation of specific E-Box CpG site is also negatively related to the mRNA expression of GH in pituitary. Taken together, our data provide an epigenetic mechanism of explicating the sex duality in phenotypic plasticity of growth rate in male and female of Nile tilapia.

  18. Characterization of fatty acid delta-6 desaturase gene in Nile tilapia and heterogenous expression in Saccharomyces cerevisiae.

    Science.gov (United States)

    Tanomman, Supamas; Ketudat-Cairns, Mariena; Jangprai, Araya; Boonanuntanasarn, Surintorn

    2013-10-01

    Fatty acid delta-6 desaturase (fads2)-like gene from Nile tilapia (Oreochromis niloticus) was characterized and designated as oni-fads2. The Oni-FADS2 showed the typical structure of microsomal FADS2. The presence of oni-fads2 transcripts in unfertilized eggs demonstrated the maternal role of Nile tilapia in providing the oni-fads2 transcript in their eggs. In addition, the expression of oni-fads2 was detectable in embryos throughout the hatching stage. Real-time reverse transcription-PCR revealed that oni-fads2 was expressed at a high level in all the brain regions, liver, and testis. Recombinant yeast (RY) was generated by transformation of Saccharomyces cerevisiae with the plasmid containing oni-fads2 driven by the Gal1 promoter (pYoni-fads2). The conspicuous expression of RY was detectable by RT-PCR after induction with galactose for 24h. When RY was induced with galactose, it exhibited 39% and 7% of delta-6 desaturase (∆6) activity toward C18:2n6 and C18:3n3, respectively. Additionally, it displayed 4% of delta-5 desaturase (∆5) activity toward C20:3n6, indicating that Oni-FADS2 had ∆5 and ∆6 bifunction.

  19. VALIDATION OF THE ACETO-CARMINE TECHNIQUE FOR EVALUATING PHENOTYPIC SEX IN NILE TILAPIA (Oreochromis niloticus FRY

    Directory of Open Access Journals (Sweden)

    Wassermann Gustavo Javier

    2002-01-01

    Full Text Available In this study a method for evaluating phenotypic sex in Nile tilapia was validated. A technique that uses aceto-carmine squash mounts to stain the entire gonadal tissue for microscopic examination (Method 2- squash mounts was compared with a technique based on traditional histology. Approximately 2600 Nile tilapia fry weighing and measuring, respectively, between 0.25-2.50g and 26-53mm, aged 35 to 60 days after hatch (DAH, were sexed using this methodology. In situ microscopic examination on the gonads was also performed. A reliable sexing using squash mount was possible with fish weighing more than 0.500g, 45-47 DAH. Results from microscopic observation using the aceto-carmine stain coincided 100% with the histological examination. Male gonadal tissue was characterized by the presence of cysts containing spermatogonia and spermatocytes, while females were easily identified by the presence of oocytes at the perinucleolar stage. The technique proved to be efficient not only in terms of evaluating sex proportion in fish but also because it allows immediate evaluation of gonadal sex and demands less time and labour.

  20. Pelleting and extrusion effects on the digestibility of alternative ingredients in Northeast Semi-arid for Nile tilapia

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    Lilian Dena dos Santos

    2014-12-01

    Full Text Available The apparent digestibility of nutrients and energy from cassava (RM, goats / sheep by products meal (FR and maniçoba hay meal (FM was evaluated for Nile tilapia in feed processing, as palletized and extruded form. The apparent digestibility of crude protein and energy for the RM, FR and FM in pelletized diets were respectively 77.97 and 65.86%, 93.79 and 88.62%, 54.62 and 28.64%. The apparent digestibility of crude protein and energy for the RM, FR and FM in extruded feeds were respectively 83.98 and 81.77%, 62.55 and 89.81%, 52.73 and 28.09%. The extrusion contributed to the improvement of energy digestibility of the RM, but reduced the apparent digestibility of the protein fraction of FR. The values of digestible nutrients in the present work, regardless of the processing, suggest a good potential for the use of cassava flour and goats/sheep by products meal in the composition of diets for Nile tilapia, unlike hay maniçoba hay meal.

  1. EVALUATION OF FERMENTED MANGO (Mangifera indica SEED MEAL IN THE PRACTICAL DIET OF NILE TILAPIA, (Oreochromis niloticus FINGERLINGS

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    Samuel Olubodun Obasa

    2013-10-01

    Full Text Available This study evaluated the use of fermented mango (Mangifera indica seed meal (FMS to substitute yellow maize in the practical diet for Nile tilapia, Oreochromis niloticus fingerlings (4.76±0.32 g. Five iso-nitrogeneous (35% crude protein and approximately iso-energetic (3400 ME Kcal/kg dietsin which yellow maize was replaced by FMSat 0% (FMS0/Control diet, 25% (FMS25, 50% (FMS50, 75% (FMS75 and 100% (FMS100 levels were formulated. The fish were fed on the diets at 5% body weight for 84 days. Alkaloids were highest (2.32% among the anti-nutritional factors analyzed in FMS, while oxalate (0.84% was lowest. Potassium was highest (8.91 mg/g among the minerals, while copper was lowest (0.01 mg/g. Weight gain, specific growth rate and feed conversion ratio were similar (p>0.05 in fish fed diets FMS0 and FMS50. The fish fed diet FMS0 had the highest protein efficiency ratio (1.88. Protein digestibility decreased (p<0.05 as dietary FMS increased, while carbohydrate digestibility gave an inverse relationship. Results obtained show that FMS could replace yellow maize at 50% level without affecting growth, nutrient utilization and apparent protein digestibility in diets for Nile tilapia fingerlings.

  2. Growth of Nile tilapia post-larvae from broodstock fed diet with different levels of digestible protein and digestible energy

    Directory of Open Access Journals (Sweden)

    Silia Maria de Negreiros Sousa

    2013-08-01

    Full Text Available This study was carried out to evaluate the influence of different levels of digestible energy and digestible protein in diets of Nile tilapia (Oreochromis niloticus broodstock on offspring growth during sex reversal stage. A total of 2,700 post-larvae (8.2±0.001 mg derived from breeders fed nine diets with distinct levels of digestible protein (28, 34 and 40% DP and digestible energy (2,800; 3,400; and 4,000 kcal DE.kg-1 were stored in twenty-seven 70 L tanks. After 30 days of growth, their average final weight (AFW, g, average weight gain (AWG, g, final standard length (SL, cm, condition factor (CF, specific growth rate (SGR, %/day, stock uniformity (UNI, %, survival (SUR, % and sex reversal rate (SRR, % were measured. Although female nutrition is thought to influence the performance or quality of progeny during early life stages, no influence of diets supplied to broodstock was detected on any parameter. Nonetheless, the offspring presented commercially satisfactory growth rates. Thus, diets containing 28% of digestible protein and 2,800 kcal of digestible energy.kg of diet-1 can be used to feed Nile tilapia broodstock without jeopardizing offspring performance during the sex reversal phase.

  3. Preliminary study of acceleration based sensor to record nile tilapia (Oreochromis niloticus) feeding behavior at water surface

    Science.gov (United States)

    Subakti, Aji; Khotimah, Zarah F.; Darozat, Fajar M.

    2017-01-01

    In this preliminary study, the acceleration based sensor was developed to monitor the activity of Nile tilapia (Oreochromis niloticus) feeding behavior at the water surface. This study was conducted for three weeks in a fish pond with 40 m2 in size, stocked with 850 fingerlings of Nile tilapia strain Nirwana-2 (average biomass of 13 g, fed four times a day at 8 am, 12 pm, 4 pm, and 8 pm). The acceleration sensor system was installed floating in the pond and was designed in a way so that the xz plane of the sensor will be parallel with water surface, while the y-axis will be pointing downward. By sensing the acceleration caused by the surface wave, the activities of fish near surface water could be monitored. The result showed that there were three distinctive patterns could be observed which was related to the feeding activity of fish. Generally, it can be concluded that this acceleration based sensor system can be integrated with automatic feeder machine, in particular by analyzing the recorded patter, it is possible to monitor when the fish stop eating, and so the right amount of feed could be given to the fish.

  4. The culture of Tilapia species in tropical and subtropical conditions

    Directory of Open Access Journals (Sweden)

    De Maeseneer, J.

    1984-01-01

    Full Text Available Although since long known by African fishermen it is only in the last 40 years that Tilapia has been recognized as one of the most promising groups of fish species for culture. The initial successes for culture in Central Africa were followed by several failures mainly because of excessive breeding and early sexual maturity in shallow waterbodies as ponds. From the present knowledge it appears that tilapia has a great future for increasing the productivity in unmanaged environments as man-made lakes and reservoirs primarily destined for the production of hydro-electricity. Careful stocking of paddies and irrigation canals can solve a number of biological problems associated with them and provide an additional though valuable high-protein food source. Great future offers also the culture of tilapia in traditional pond culture especially in polyculture with members of the carp family, mullets and waterfowl in areas of the tropical and subtropical belt. In coastal ponds T, mossambica is a valuable species for sanitary reasons. The culture of tilapia in small farm ponds often meets with failure owing to excessive breeding and stunting unless the all-male technique can be applied through government input and encouragement. As a rule this type of production will be the least attractive. Although Tilapia spp. do not achieve the largest individu al growth their tolerance towards adverse conditions and their acceptance of a wide variety of foodstuffs, primarily waste products from agriculture, their resistance to diseases and (at least in some species their tolerance of crowded environments make them suitable subject for cultures in raceways, circular tanks and cages. Through heavy inputs of water and pelletized feeds nearly incredible annual yields as 2 000 tonnes per ha of water surface (1 and more were realized. This means that this type of production surpasses by far any other known form of animal husbandry but it needs high technological input (thus

  5. Vitamin C modulates cadmium-induced hepatic antioxidants' gene transcripts and toxicopathic changes in Nile tilapia, Oreochromis niloticus.

    Science.gov (United States)

    El-Sayed, Yasser S; El-Gazzar, Ahmed M; El-Nahas, Abeer F; Ashry, Khaled M

    2016-01-01

    Cadmium (Cd) is one of the naturally occurring heavy metals having adverse effects, while vitamin C (L-ascorbic acid) is an essential micronutrient for fish, which can attenuate tissue damage owing to its chain-breaking antioxidant and free radical scavenger properties. The adult Nile tilapia fish were exposed to Cd at 5 mg/l with and without vitamin C (500 mg/kg diet) for 45 days in addition to negative and positive controls fed with the basal diet and basal diet supplemented with vitamin C, respectively. Hepatic relative mRNA expression of genes involved in antioxidant function, metallothionein (MT), glutathione S-transferase (GST-α1), and glutathione peroxidase (GPx1), was assessed using real-time reverse transcription polymerase chain reaction (RT-PCR). Hepatic architecture was also histopathologically examined. Tilapia exposed to Cd exhibited upregulated antioxidants' gene transcript levels, GST-⍺1, GPx1, and MT by 6.10-, 4.60-, and 4.29-fold, respectively. Histopathologically, Cd caused severe hepatic changes of multifocal hepatocellular and pancreatic acinar necrosis, and lytic hepatocytes infiltrated with eosinophilic granular cells. Co-treatment of Cd-exposed fish with vitamin C overexpressed antioxidant enzyme-related genes, GST-⍺1 (16.26-fold) and GPx1 (18.68-fold), and maintained the expression of MT gene close to control (1.07-fold), averting the toxicopathic lesions induced by Cd. These results suggested that vitamin C has the potential to protect Nile tilapia from Cd hepatotoxicity via sustaining hepatic antioxidants' genes transcripts and normal histoarchitecture.

  6. A Comparison of the Beneficial Effects of Live and Heat-Inactivated Baker's Yeast on Nile Tilapia: Suggestions on the Role and Function of the Secretory Metabolites Released from the Yeast

    National Research Council Canada - National Science Library

    Ran, Chao; Huang, Lu; Liu, Zhi; Xu, Li; Yang, Yalin; Tacon, Philippe; Auclair, Eric; Zhou, Zhigang

    2015-01-01

    .... In this study, the involvement and extent to which the viability of yeast cells and thus the secretory metabolites released from the yeast contribute to effects of baker's yeast was investigated in Nile tilapia...

  7. A Comparison of the Beneficial Effects of Live and Heat-Inactivated Baker's Yeast on Nile Tilapia: Suggestions on the Role and Function of the Secretory Metabolites Released from the Yeast: e0145448

    National Research Council Canada - National Science Library

    Chao Ran; Lu Huang; Zhi Liu; Li Xu; Yalin Yang; Philippe Tacon; Eric Auclair; Zhigang Zhou

    2015-01-01

    .... In this study, the involvement and extent to which the viability of yeast cells and thus the secretory metabolites released from the yeast contribute to effects of baker's yeast was investigated in Nile tilapia...

  8. Yeast as probiotic for Nile tilapia during the sexual reversion phase Levedura como probiótico na reversão sexual da tilápia do Nilo

    National Research Council Canada - National Science Library

    Leda Maria Saragiotto Colpini; Arthur dos Santos Mascioli; Mateus Matiuzzi da Costa; Carmino Hayashi; Fábio Meurer; André Freccia

    2008-01-01

    The effect of including Saccharomyces cerevisiae (SC) as probiotic in rations for Nile tilapia during sexual reversion on performance, percentage of sexual reversion and intestine settling, under sanitary challenge, was evaluated...

  9. 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

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    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%.

  10. The study on the candidate probiotic properties of encapsulated yeast, Saccharomyces cerevisiae JCM 7255, in Nile Tilapia (Oreochromis niloticus).

    Science.gov (United States)

    Pinpimai, Komkiew; Rodkhum, Channarong; Chansue, Nantarika; Katagiri, Takayuki; Maita, Masashi; Pirarat, Nopadon

    2015-10-01

    Saccharomyces cerevisiae JCM 7255 was tested as a probiotic candidate in tilapia after encapsulating and freeze drying. Viability and morphology during storage and during transit through simulated gut and bile conditions were determined. Growth performance, anti-streptococcal activity and gut mucosal immune parameters were also tested. The viability of encapsulated yeasts was significantly high in simulated gastric and bile conditions and remained high after storage at room temperature for 14 days. The morphology of free S. cerevisiae revealed rough, bumpy, ruptured surface during incubation in gut and bile conditions. Agar spot anti-streptococcal activity showed inhibition of 20 out of 30 strains of Streptococcus agalactiae. Supplementation improved the intestinal structure and growth performance in tilapias. Intraepithelial lymphocytes in the proximal intestine were significantly observed. Lower cumulative mortality after the oral streptococcal challenge was also seen. The results suggest that encapsulated S. cerevisiae JCM 2755 could be a potential probiotic strain in tilapia culture.

  11. 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 ...

  12. Spring forward with improved Nile tilapia Oreochromis niloticus resistant to Streptococcus iniae and Streptococcus agalactiae IB

    Science.gov (United States)

    Tilapia aquaculture worldwide is valued around US $ 7 billion. Tilapia are an important source of protein for domestic (top 5 most consumed seafoods) and global food security. Two gram postitive bacteria, Streptococcus iniae and S. agalactiae, are responsible for billion dollar losses annually. Gen...

  13. Gill histopathological alterations in Nile tilapia, Oreochromis niloticus exposed to treated sewage Water

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    António Fontaínhas-Fernandes

    2008-10-01

    Full Text Available Adult Nile tilapia, Oreochromis niloticus, of both sexes were exposed in wastewater from a sewage treatment plant for a period of 4 days. Gill samples were collected after 24, 48, 72 and 96 h and histopathological changes were analyzed by light and scanning electronic microscopy. Gill epithelium of control O. niloticus (freshwater group was similar to that of other teleosts, while histopathological lesions were observed in exposed fishes. The main histopathological changes were edema, lifting of lamellar and filamentar epithelia and lamellar fusion. Cell proliferation with consequent thickening of the filament epithelium was also found in fishes exposed to the treated sewage water. The severity of the lesions increased with the time of exposure, namely the hyperplasia of the epithelial cells with proliferation of filamentar epithelium and fusion of lamellae observed at 96 h. Additionally, several histopathological results obtained by light microscopy were confirmed through scanning microscopy.Tilápias adultas, Oreochromis niloticus, de ambos os sexos foram expostas em águas residuais de uma estação de tratamento de esgoto durante 4 dias. Amostras de brânquia foram recolhidas após 24, 48, 72 e 96 h e as alterações histopatológicas foram analisadas por microscopia óptica e eletrônica de varredura. O epitélio da brânquia do grupo controle apresentou uma morfologia similar à de outros peixes teleosteos, enquanto foram observadas lesões nos peixes expostos. As principais alterações histopatológicas foram edema, destacamento dos epitélios lamelar e filamentar e fusão lamelar. Os peixes expostos às águas residuais mostraram também proliferação celular com consequente aumento da espessura do filamento branquial. A severidade das lesões aumentou com o tempo de exposição, nomeadamente a hiperplasia das células epiteliais com proliferação do epitélio filamentar e fusão das lamelas observadas preferencialmente às 96 h

  14. 3种品系尼罗罗非鱼生长及高密度胁迫后生理响应变化的比较%Comparison on growth performance in three different strains of Nile tilapia and physiological responses after short-term high stocking den-sity stress

    Institute of Scientific and Technical Information of China (English)

    强俊; 杨弘; 何杰; 王辉; 徐跑; 朱志祥

    2014-01-01

    To establish the growth performance and physiological responses after short-term crowding stress, three Nile tilapia (Oreochromis niloticus) strains (GIFT tilapia, new GIFT tilapia and Egypt Nile tilapia) were compared in terms of certain body indices. At day 100 of the experiment, tilapias in the experimental group were exposed to short-term crowding stress to evaluate the serum biochemical parameters and liver HSP70 mRNA expression before and after stress. The results showed that GIFT tilapia had the best growth rate, and the growth of New GIFT tilapia ranked second;however, no significant difference was observed between the two strains. The growth rate of Egypt Nile tilapia was the slowest. Viscerosomatic indices of GIFT tilapia and New GIFT tilapia were significantly higher than those of the Egypt Nile tilapia. There was no significant difference in the condition factor among the three groups. At the end of the feed-ing trial, 40 fish per bucket were exposed to crowding stress (100g/L) for 48h, The effects of a short-term exposure on the physiological responses of fish were determined before stress (0h) and at 6, 12, 24 or 48 h post-crowding. The se-rum total protein, glucose, glutamic-oxaloacetic transaminase (AST), cholesterol, lysozyme (LSZ) level and hepatic Hsp70mRNA levels in GIFT tilapia and New GIFT tilapia initially increased and then decreased over48 h of crowding stress. Compared with the level at 0 h, the serum cortisol level of the Egypt Nile tilapia was not significantly difference at 48 h post-stress, but the levels in GIFT tilapia and New GIFT tilapia were significantly higher than at 0h. The serum LSZ activity and HSP70 mRNA levels of the Egypt Nile tilapia at 48 h were significantly higher than at 0 h. Overall, the results indicated that short term, high density crowding enhanced the use of serum glucose and triglyceride, but caused liver damage in tilapia. The ability of the Egypt Nile tilapia to resist high density stress is stronger than

  15. Redução da proteína da dieta com base no conceito de proteína ideal para tilápias-do-nilo (Oreochromis niloticus criadas em tanques-rede Dietary protein reduction based on ideal protein concept for Nile Tilapia (Oreochromis niloticus cultured in net pens

    Directory of Open Access Journals (Sweden)

    Daniele Botaro

    2007-06-01

    Full Text Available Avaliou-se o desempenho de tilápias-do-nilo (Oreochromis niloticus criadas em tanques-rede e alimentadas com dietas contendo 27,0 (controle; 25,2; 24,3 e 22,7% de proteína digestível. Aminoácidos cristalinos (L-lisina, DL-metionina e L-treonina foram adicionados à dieta considerando o conceito de proteína ideal e simulando o perfil de aminoácidos da dieta controle. Os peixes (34,63±19 g foram alimentados manualmente com dietas isoenergéticas (3.075 kcal de energia digestível/kg de dieta até saciedade aparente, três vezes ao dia, durante 91 dias. Utilizou-se um delineamento inteiramente casualizado, com quatro tratamentos, três repetições e 25 peixes/unidade experimental. Não foram observados efeitos dos níveis de proteína digestível sobre o ganho de peso, a conversão alimentar, a taxa de eficiência protéica, o peso da carcaça eviscerada, o rendimento de carcaça, o peso e o rendimento de filé, a sobrevivência e o hematócrito. Houve efeito quadrático dos níveis de proteína digestível sobre o consumo; o maior valor foi estimado para a dieta contendo 24,41% de proteína digestível e excreção de nitrogênio, na qual o melhor resultado estimado foi obtido com peixes que receberam a dieta contendo 24,92% de PD. Com a redução nos níveis de proteína digestível, observou-se aumento linear na retenção de nitrogênio. É possível reduzir o nível de proteína digestível, de 27 (29,1% de PB para 24,3% (26,6% de PB, em dietas para tilápias-do-nilo criadas em tanques-rede. Essa redução deve ser feita por meio da suplementação de aminoácidos (com base no conceito de proteína ideal, considerando o desempenho e o custo da dieta/kg ganho em filé.This study was carried out to evaluate the performance of Nile tilapia, cultured in net pens, and fed diets containing 27.0 (control, 25.2, 24.3, and 22.7% of digestible protein. Crystalline amino acids (L-lysine, DL-methionine and L-threonine were added to keep amino acid

  16. Dietary Probiotic in production systems of Nile tilapia: effect on growth, balance of N and P nutrient retention and economic viability

    Directory of Open Access Journals (Sweden)

    Monique Bayer Wild

    2014-02-01

    Full Text Available The objectives were estimate the balance of N and P, the retention of K, Ca, Mg, Cu, Fe, Mn, Zn, Cd, Pb and Cr, and the economic viability in a culture system of Nile tilapia subjected to the addition of B. subtilis and B. cereus in the diet. The analysis of nutrients in the diet and in the fish were carry out for the calculations of the rate of nutrient retention efficiency (RNRE, protein efficiency ratio (PER and efficiency of nitrogen retention (NER. The experimental design for the content of nutrients in the soil on collection times and collection site at the end of cultivation was in factorial 4 x 2 with five replications and to the NER, and PER in fish RNRE was completely randomized with four treatments and five replicates. The analyses of variance were employed, followed by Tukey test (p<0.05 and regression analysis. The addition of probiotics in the diet influenced (p<0.05 only the efficiency of retention of Mn. The PER it was lower (p<0.05 for the addition of isolated B. subtilis (0.89% in comparison with feed and B. cereus (1.12% and free of probiotic food (1.11%. The average values of N, Cu, Mn and Cr were higher in the sediment of the collection box and P concentrations were higher (p<0.05 in the soil. The nutrients N, P, Cu and Fe had a significant increase (p<0.05 in the soil and sediment of ponds of the culture. The diet added to B. subtilis provides worse results of PER and lower NER results in production of large-scale tilapia. The cultivation leads to retention of nitrogen and phosphorus in the soil and sediment collection box. This effect can be minimized in accordance with the increase of ERN and the rate of phosphorus retention efficiency (RPRE in fish.

  17. Efficacy of QCDCR formulated CpG ODN 2007 in Nile tilapia against Streptococcus iniae and identification of upregulated genes.

    Science.gov (United States)

    Pridgeon, Julia W; Klesius, Phillip H; Mu, Xingjiang; Yancey, Robert J; Kievit, Michele S; Dominowski, Paul J

    2012-01-15

    The potential of using a QCDCR (quilA:cholesterol:dimethyl dioctadecyl ammonium bromide:carbopol:R1005 glycolipid) formulated CpG oligodeoxynucleotide (ODN), ODN 2007, to confer protection in Nile tilapia against Streptococcus iniae infection was evaluated in this study. At two days post treatment, QCDCR formulated ODN 2007 elicited significant (Psubtractive cDNA library. Quantitative PCR revealed that 44 ESTs were significantly (P10-fold) and 15 moderately (<10-fold) upregulated ESTs. Of all ESTs, putative peroxisomal sarcosine oxidase was upregulated the highest. The 69 ESTs only included six genes that had putative functions related to immunity, of which only two (putative glutaredoxin-1 and carboxypeptidase N catalytic chain) were confirmed to be significantly upregulated. Our results suggest that the protection elicited by ODN 2007 is mainly through innate immune responses directly or indirectly related to immunity.

  18. Evaluation of the dairy/yeast prebiotic, GroBiotic-A, in the diet of the juvenile Nile tilapia, Oreochromis niloticus

    Science.gov (United States)

    Tilapia production ranks among the highest worldwide due to their fast growth and ability to thrive under various culture conditions. However, tilapias are still susceptible to outbreaks of systemic disease caused by opportunistic bacterial pathogens such as Streptococcus inaie. These epizootic ev...

  19. Molecular characterization of Galectin-8 from Nile tilapia (Oreochromis niloticus Linn.) and its response to bacterial infection.

    Science.gov (United States)

    Unajak, Sasimanas; Pholmanee, Nutthida; Songtawee, Napat; Srikulnath, Kornsorn; Srisapoome, Prapansak; Kiataramkul, Asama; Kondo, Hidehiro; Hirono, Ikuo; Areechon, Nontawith

    2015-12-01

    Galectins belong to the family of galactoside-binding proteins and play a major role in the immune and inflammatory responses of vertebrates and invertebrates. The galectin family is divided into three subtypes based on molecular structure; prototypes, chimera types, and tandem-repeated types. We isolated and characterized the cDNA of galectin-8 (OnGal-8) in Nile tilapia (Oreochromis niloticus). OnGal-8 consisted of a 966 bp open reading frame (ORF) that encoded a 321 amino acid protein (43.47 kDa). Homology and phylogenetic tree analysis suggested the protein was clustered with galectin-8s from other animal species and shared at least 56.8% identity with salmon galectin-8. Structurally, the amino acid sequence included two distinct N- and C- terminus carbohydrate recognition domains (CRDs) of 135 and 133 amino acids, respectively, that were connected by a 39 amino acid polypeptide linker. The N- and C-CRDs contained two conserved WG-E-I and WG-E-T motifs, suggesting they have an important role in mediating the specific interactions between OnGal-8 and saccharide moieties such as β-galactoside. The structure of OnGal-8 was characterized by a two-fold symmetric pattern of 10-and 12-stranded antiparallel ß-sheets of both N- and C-CRDs, and the peptide linker presumably formed a random coil similar to the characteristic tandem-repeat type galectin. The expression of OnGal-8 in healthy fish was highest in the skin, intestine, and brain. Experimental challenge of Nile tilapia with S. agalactiae resulted in significant up-regulation of OnGal-8in the spleen after 5 d. Our results suggest that OnGal-8 is involved in the immune response to bacterial infection.

  20. Morphological characteristics of ovarian development of two Nile tilapia (Oreochromis niloticus strains in mixed-culture systems Características morfológicas do desenvolvimento ovariano de duas linhagens de tilápia-do-nilo (Oreochromis niloticus, em sistemas de cultivo misto

    Directory of Open Access Journals (Sweden)

    P.R. Neves

    2009-10-01

    Full Text Available This study was carried out to morphologically characterize and classify the stages of gonad development in different Nile tilapia strains (Oreochromis niloticus. Eighty-four and ninety-two ovaries from Bouaké and Chitralada strains, respectively, were evaluated at different ovarian developmental phases: initial (104 days of culture, intermediate (152 days of culture, and the final (279 days of culture. The ovaries were microscopically evaluated and submitted to histological processing and hematoxylin-eosin staining to determine their characteristics and be classified. No morphological differences in ovaries between strains were observed during the initial phase (stage A - immature. During the intermediate growing phase, higher gonad development was observed for Chitralada strain (stage B - maturation in comparison with Bouaké strain (stage A - immature. During the final growing phase, no differences between strains were observed for morphological characteristics (stage C - mature. Despite the similarities in reproductive behavior of the Bouaké and Chitralada females at the end of the final growing phase (gain weight phase, differences for macroscopic and microscopic aspects and oocytes during the initial and intermediate growing phases of the strains were observed.Este trabalho teve como objetivo caracterizar morfologicamente e classificar os estádios de desenvolvimento gonadal de tilápias do Nilo (Oreochromis niloticus de linhagens distintas. Foram avaliados 84 ovários da linhagem Bouaké e 92 da linhagem Chitralada, em diferentes fases de desenvolvimento: inicial (imatura - 104 dias de cultivo, intermediária (crescimento - 152 dias de cultivo e final (ganho de peso - 279 dias de cultivo. Os ovários foram analisados macroscopicamente e submetidos a procedimento histológico, corados com hematoxilina-eosina, para determinação das características microscópicas e subsequente classificação. Não foram observadas diferenças morfol

  1. An Overview of Vaccination Strategies and Antigen Delivery Systems for Streptococcus agalactiae Vaccines in Nile Tilapia (Oreochromis niloticus).

    Science.gov (United States)

    Munang'andu, Hetron Mweemba; Paul, Joydeb; Evensen, Øystein

    2016-12-13

    Streptococcus agalactiae is an emerging infectious disease adversely affecting Nile tilapia (Niloticus oreochromis) production in aquaculture. Research carried out in the last decade has focused on developing protective vaccines using different strategies, although no review has been carried out to evaluate the efficacy of these strategies. The purpose of this review is to provide a synopsis of vaccination strategies and antigen delivery systems currently used for S. agalactiae vaccines in tilapia. Furthermore, as shown herein, current vaccine designs include the use of replicative antigen delivery systems, such as attenuated virulent strains, heterologous vectors and DNA vaccines, while non-replicative vaccines include the inactivated whole cell (IWC) and subunit vaccines encoding different S. agalactiae immunogenic proteins. Intraperitoneal vaccination is the most widely used immunization strategy, although immersion, spray and oral vaccines have also been tried with variable success. Vaccine efficacy is mostly evaluated by use of the intraperitoneal challenge model aimed at evaluating the relative percent survival (RPS) of vaccinated fish. The major limitation with this approach is that it lacks the ability to elucidate the mechanism of vaccine protection at portals of bacterial entry in mucosal organs and prevention of pathology in target organs. Despite this, indications are that the correlates of vaccine protection can be established based on antibody responses and antigen dose, although these parameters require optimization before they can become an integral part of routine vaccine production. Nevertheless, this review shows that different approaches can be used to produce protective vaccines against S. agalactiae in tilapia although there is a need to optimize the measures of vaccine efficacy.

  2. Effect of the establishment of dominance relationships on cortisol and other metabolic parameters in Nile tilapia (Oreochromis niloticus

    Directory of Open Access Journals (Sweden)

    Corrêa S.A.

    2003-01-01

    Full Text Available The objective of the present study was to investigate the influence of the establishment of dominance relationships and social stress on plasma cortisol and metabolite levels in Nile tilapia (Oreochromis niloticus. During the 30-day experiment, the fish weighing 236 ± 29 g were kept in individual aquaria, except for two pairings lasting 6 h each. Blood samples were taken from the animals before and after pairing. Display, approach, attack, rebuff, chase flight, and coloration were carried out on days 16 and 30. Activities and behaviors characteristic of the establishment of dominance relationships were described. It was possible to classify all experimental fish (N = 30 as dominant or subordinate. No differences were detected between dominant (N = 15 and subordinate (N = 15 fish during isolation or after pairing in cortisol (isolated: 5.76 ± 0.98 vs 5.42 ± 0.63; paired: 10.94 ± 1.62 vs 11.21 ± 2.45 µg/dl, glucose (isolated: 60.02 ± 4.9 vs 67.85 ± 16.16; paired: 110.44 ± 15.72 vs 136.26 ± 22.46 mg/dl, triglyceride (isolated: 167.87 ± 5.06 vs 185.68 ± 7.24; paired: 210.85 ± 13.40 vs 221.82 ± 12.70 mg/dl or total protein levels (isolated: 7.01 ± 0.42 vs 6.69 ± 0.59; paired: 9.21 ± 0.62 vs 9.51 ± 0.66 g/dl. However, when isolated (N = 30 and paired (N = 30 tilapia were compared, there were significant differences in cortisol and metabolite levels. The similar response presented by dominant and subordinate tilapia indicates that establishment of dominance relationships was a stressor for both groups.

  3. An Overview of Vaccination Strategies and Antigen Delivery Systems for Streptococcus agalactiae Vaccines in Nile Tilapia (Oreochromis niloticus)

    Science.gov (United States)

    Munang’andu, Hetron Mweemba; Paul, Joydeb; Evensen, Øystein

    2016-01-01

    Streptococcus agalactiae is an emerging infectious disease adversely affecting Nile tilapia (Niloticus oreochromis) production in aquaculture. Research carried out in the last decade has focused on developing protective vaccines using different strategies, although no review has been carried out to evaluate the efficacy of these strategies. The purpose of this review is to provide a synopsis of vaccination strategies and antigen delivery systems currently used for S. agalactiae vaccines in tilapia. Furthermore, as shown herein, current vaccine designs include the use of replicative antigen delivery systems, such as attenuated virulent strains, heterologous vectors and DNA vaccines, while non-replicative vaccines include the inactivated whole cell (IWC) and subunit vaccines encoding different S. agalactiae immunogenic proteins. Intraperitoneal vaccination is the most widely used immunization strategy, although immersion, spray and oral vaccines have also been tried with variable success. Vaccine efficacy is mostly evaluated by use of the intraperitoneal challenge model aimed at evaluating the relative percent survival (RPS) of vaccinated fish. The major limitation with this approach is that it lacks the ability to elucidate the mechanism of vaccine protection at portals of bacterial entry in mucosal organs and prevention of pathology in target organs. Despite this, indications are that the correlates of vaccine protection can be established based on antibody responses and antigen dose, although these parameters require optimization before they can become an integral part of routine vaccine production. Nevertheless, this review shows that different approaches can be used to produce protective vaccines against S. agalactiae in tilapia although there is a need to optimize the measures of vaccine efficacy. PMID:27983591

  4. Individual protein balance strongly influences δ15N and δ13C values in Nile tilapia, Oreochromis niloticus

    Science.gov (United States)

    Gaye-Siessegger, Julia; Focken, Ulfert; Abel, Hansjörg; Becker, Klaus

    Although stable isotope ratios in animals have often been used as indicators of the trophic level and for the back-calculation of diets, few experiments have been done under standardized laboratory conditions to investigate factors influencing δ15N and δ13C values. An experiment using Nile tilapia [Oreochromis niloticus (L.)] was therefore carried out to test the effect of different dietary protein contents (35.4, 42.3, and 50.9%) on δ15N and δ13C values of the whole tilapia. The fish were fed the isoenergetic and isolipidic semi-synthetic diets at a relatively low level. δ15N and δ13C values of the lipid-free body did not differ between the fish fed the diets with different protein contents, but the trophic shift for N and C isotopes decreased with increasing protein accretion in the individual fish, for N from 6.5‰ to 4‰ and for C in the lipid-free body from 4‰ to 2.5‰. This is the first study showing the strong influence of the individual protein balance to the degree to which the isotopic signature of dietary protein was modified in tissue protein of fish. The extrapolation of the trophic level or the reconstruction of the diet of an animal from stable isotope ratios without knowledge of the individual physiological condition and the feeding rate may lead to erroneous results.

  5. Flow cytometric evaluation of antibiotic effects on viability and mitochondrial function of refrigerated spermatozoa of Nile tilapia

    Science.gov (United States)

    Segovia, M.; Jenkins, J.A.; Paniagua-Chavez, C.; Tiersch, T.R.

    2000-01-01

    Improved techniques for storage and evaluation of fish sperm would enhance breeding programs around the world. The goal of this study was to test the effect of antibiotics on refrigerated sperm from Nile tilapia (Oreochromis niloticus) by use of flow cytometry with 2 dual-staining protocols for objective assessment of sperm quality. Concentrations of 1 x 109 sperm/mL were suspended in Ringer's buffer at 318 mOsmol/kg (pH 8.0). The fluorescent stains Sybr 14 (10 ??M), propidium iodide (2.4 mM), and rhodamine 123 (0.13 ??M) were used to assess cell viability and mitochondrial function. Three concentrations of ampicillin, gentamicin, and an antibiotic/antimycotic solution were added to fresh spermatozoa. Motility estimates and flow cytometry measurements were made daily during 7 d of refrigerated storage (4 ??C). The highest concentrations of gentamicin and antibiotic/antimycotic and all 3 concentrations of ampicillin significantly reduced sperm viability. The highest of each of the 3 antibiotic concentrations significantly reduced mitochondrial function. This study demonstrates that objective sperm quality assessments can be made using flow cytometry and that addition of antibiotics at appropriate concentrations can lengthen refrigerated storage time for tilapia spermatozoa. With minor modifications, these protocols can be adapted for use with sperm from other species and with other tissue types.

  6. Cichlidogyrus sclerosus (Monogenea: Ancyrocephalinae) and its host, the Nile tilapia (Oreochromis niloticus), as bioindicators of chemical pollution.

    Science.gov (United States)

    Sanchez-Ramirez, Claudia; Vidal-Martinez, Victor M; Aguirre-Macedo, Maria L; Rodriguez-Canul, Rossanna P; Gold-Bouchot, Gerardo; Sures, Bernd

    2007-10-01

    Experimental results showed that the gill monogenean Cichlidogyrus sclerosus and its host, the Nile tilapia Oreochromis niloticus, exhibited significant numerical and physiological responses after exposure to sediments polluted with polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls, and heavy metals in comparison with control fishes. After 15 days of exposure, C. sclerosus abundance significantly increased in treatments with low to fairly high sediment pollutant concentrations, but declined at high sediment pollutant concentrations. Hypertrophy and hyperplasia in secondary gill lamellae and the spleen melanomacrophage centers were significantly higher at extremely high sediment pollutant concentrations compared with the controls. Spleen lymphocyte and monocyte counts were significantly lower at extremely high sediment pollutant concentrations and were significantly correlated with high fluorescent aromatic compound concentrations measured as PAH exposure indicators. A multivariate redundancy analysis showed significant statistical association between sediment pollutant concentration, C. sclerosus abundance, and tilapia physiological variables. The polluted sediments negatively affected monogenean abundance and induced immunosuppression in hosts, consequently increasing histological damage in hosts and allowing persistent C. sclerosus infection. This study documents evidence suggesting that C. sclerosus and its host are indeed excellent models to test environmental quality in tropical freshwater ecosystems.

  7. Individual protein balance strongly influences delta15N and delta13C values in Nile tilapia, Oreochromis niloticus.

    Science.gov (United States)

    Gaye-Siessegger, Julia; Focken, Ulfert; Abel, Hansjörg; Becker, Klaus

    2004-02-01

    Although stable isotope ratios in animals have often been used as indicators of the trophic level and for the back-calculation of diets, few experiments have been done under standardized laboratory conditions to investigate factors influencing delta(15)N and delta(13)C values. An experiment using Nile tilapia [ Oreochromis niloticus (L.)] was therefore carried out to test the effect of different dietary protein contents (35.4, 42.3, and 50.9%) on delta(15)N and delta(13)C values of the whole tilapia. The fish were fed the isoenergetic and isolipidic semi-synthetic diets at a relatively low level. delta(15)N and delta(13)C values of the lipid-free body did not differ between the fish fed the diets with different protein contents, but the trophic shift for N and C isotopes decreased with increasing protein accretion in the individual fish, for N from 6.5 per thousand to 4 per thousand and for C in the lipid-free body from 4 per thousand to 2.5 per thousand. This is the first study showing the strong influence of the individual protein balance to the degree to which the isotopic signature of dietary protein was modified in tissue protein of fish. The extrapolation of the trophic level or the reconstruction of the diet of an animal from stable isotope ratios without knowledge of the individual physiological condition and the feeding rate may lead to erroneous results.

  8. Shewanella putrefaciens in cultured tilapia detected by a new calcein-loop-mediated isothermal amplification (Ca-LAMP) method.

    Science.gov (United States)

    Suebsing, Rungkarn; Kampeera, Jantana; Sirithammajak, Sarawut; Pradeep, Padmaja Jayaprasad; Jitrakorn, Sarocha; Arunrut, Narong; Sangsuriya, Pakkakul; Saksmerprome, Vanvimon; Senapin, Saengchan; Withyachumnarnkul, Boonsirm; Kiatpathomchai, Wansika

    2015-12-09

    Shewanella putrefaciens is being increasingly isolated from a wide variety of sources and is pathogenic to many marine and freshwater fish. For better control of this pathogen, there is a need for the development of simple and inexpensive but highly specific, sensitive, and rapid detection methods suitable for application in field laboratories. Our colorogenic loop-mediated isothermal amplification (LAMP) assay combined with calcein (Ca-LAMP) for unaided visual confirmation of LAMP amplicons is a simple method for fish pathogen detection in cultured tilapia. Here, we describe the detection of S. putrefaciens using the same platform. As before, the method gave positive results (orange to green color change) in 45 min at 63°C with sensitivity 100 times higher than that of a conventional PCR assay, with no cross-amplification of other known fish bacterial pathogens tested. Using the assay with 389 samples of gonads, fertilized eggs, and fry of farmed Nile and red tilapia Oreochromis spp., 35% of samples were positive for S. putrefaciens. The highest prevalence was found in samples of gonads (55%) and fertilized eggs (55%) from adult breeding stocks, indicating that S. putrefaciens could be passed on easily to fry used for stocking production ponds. Tissue tropism assays revealed that the spleen showed the highest colonization by S. putrefaciens in naturally infected tilapia and that it would be the most suitable organ for screening and monitoring fish stocks for presence of the bacteria.

  9. Morphological variations of wild populations of Nile tilapia (Oreochromis niloticus) living in extreme environmental conditions in the Kenyan Rift-Valley

    OpenAIRE

    Ndiwa, T.C.; Nyingi, D. W.; Claude, J.; Agnèse, Jean-François

    2016-01-01

    In this study, we use geometric morphometric method to establish morphological differences between natural populations of Nile tilapia from two extreme environmental conditions (high temperature and salinity) in Kenya, and compare them to two populations from regions experiencing less extreme conditions. To determine genetic influence on morphology, we correlated genetic data with morphological data. The study observed significant morphological differences between all studied populations, inc...

  10. Survival, Growth and Reproduction of Non-Native Nile Tilapia II: Fundamental Niche Projections and Invasion Potential in the Northern Gulf of Mexico

    Science.gov (United States)

    2012-07-27

    2070–2099 compared to 1961–1990 under the A2 emission scenario in World Climate Research Pro- gramme’s Coupled Model Intercomparison Project phase 3...multi- model dataset [40]. Concomitantly, regional precipitation is projected to vary between 228% to 32% in the summer and 248% to 18% in winter. While...regression models were developed to predict the probabilities of Nile tilapia survival, growth, and reproduction at different combinations of

  11. Morphological re-description and phylogenetic relationship of five myxosporean species of the family Myxobolidae infecting Nile tilapia.

    Science.gov (United States)

    Abdel-Gaber, Rewaida; Abdel-Ghaffar, Fathy; Maher, Sherein; El-Mallah, Al-Mahy; Al Quraishy, Saleh; Mehlhorn, Heinz

    2017-05-11

    Freshwater fish have a major economic and nutritional importance worldwide. Myxosporeans are highly dangerous parasites that infect different fish species, causing severe damage to a large number of economically important species, especially in aquaculture. We conducted a survey of myxosporean parasites infecting Nile tilapia Oreochromis niloticus (Perciformes: Cichlidae) collected from different localities along the River Nile passing through Giza province, Egypt. Out of 100 fish specimens collected, 45 were found to be naturally infected with these parasites in the region of the trunk kidney. Light microscopic examination revealed the presence of 5 distinct myxosporean species belonging to 2 different genera, viz. Myxobolus and Triangula, belonging to the family Myxobolidae; all 5 species have been previously described. Morphological characteristics, host specificity and geographical distribution, tissue tropism, and molecular analysis of the partial sequence of small subunit ribosomal DNA gene revealed that the recovered myxosporean species described herein were genetically distinct from other myxozoan species but had 95% sequence similarity to M. cerebralis. Also, phylogenetic analysis placed the present myxosporean species in the freshwater Myxobolus clade, which is a sister group of freshwater Myxobolus/Henneguya species.

  12. Activity of Brazilian propolis against Aeromonas hydrophila and its effect on Nile tilapia growth, hematological and non-specific immune response under bacterial infection

    Directory of Open Access Journals (Sweden)

    RICARDO O. ORSI

    Full Text Available ABSTRACT The effect of the ethanolic extract of propolis (EEP on Aeromonas hydrophila was analyzed by determination of minimum inhibitory concentration (MIC. Then, the effects of crude propolis powder (CPP on growth, hemato-immune parameters of the Nile tilapia, as well as its effects on resistance to A. hydrophila challenge were investigated. The CPP (0.5, 1.0, 1.5, 2.0, 2.5 and 3.0% was added to the diet of 280 Nile tilapia (50.0 ± 5.7 g fish-1. Hemato-immune parameters were analyzed before and after the bacterial challenge. Red blood cell, hematocrit, hemoglobin, mean corpuscular volume (MCV, mean corpuscular hemoglobin concentration (MCHC, and hydrogen peroxide (H2O2 and nitric oxide (NO were evaluated. The MIC of the EEP was 13% (v/v with a bactericidal effect after 24 hours. Growth performance was significantly lower for those fish fed diets containing 2.5 and 3% of CPP compared to the control diet. Differences in CPP levels affected fish hemoglobin, neutrophils number and NO following the bacterial challenge. For others parameters no significant differences were observed. Our results show that although propolis has bactericidal properties in vitro, the addition of crude propolis powder to Nile tilapia extruded diets does not necessarily lead to an improvement of fish health.

  13. Activity of Brazilian propolis against Aeromonas hydrophila and its effect on Nile tilapia growth, hematological and non-specific immune response under bacterial infection.

    Science.gov (United States)

    Orsi, Ricardo O; Santos, Vivian G Dos; Pezzato, Luiz E; Carvalho, Pedro L P F DE; Teixeira, Caroline P; Freitas, Jakeline M A; Padovani, Carlos R; Sartori, Maria M P; Barros, Margarida M

    2017-07-31

    The effect of the ethanolic extract of propolis (EEP) on Aeromonas hydrophila was analyzed by determination of minimum inhibitory concentration (MIC). Then, the effects of crude propolis powder (CPP) on growth, hemato-immune parameters of the Nile tilapia, as well as its effects on resistance to A. hydrophila challenge were investigated. The CPP (0.5, 1.0, 1.5, 2.0, 2.5 and 3.0%) was added to the diet of 280 Nile tilapia (50.0 ± 5.7 g fish-1). Hemato-immune parameters were analyzed before and after the bacterial challenge. Red blood cell, hematocrit, hemoglobin, mean corpuscular volume (MCV), mean corpuscular hemoglobin concentration (MCHC), and hydrogen peroxide (H2O2) and nitric oxide (NO) were evaluated. The MIC of the EEP was 13% (v/v) with a bactericidal effect after 24 hours. Growth performance was significantly lower for those fish fed diets containing 2.5 and 3% of CPP compared to the control diet. Differences in CPP levels affected fish hemoglobin, neutrophils number and NO following the bacterial challenge. For others parameters no significant differences were observed. Our results show that although propolis has bactericidal properties in vitro, the addition of crude propolis powder to Nile tilapia extruded diets does not necessarily lead to an improvement of fish health.

  14. Determination of presence and quantification of cadmium, lead and copper in Nile tilapia (Oreochromis niloticus fillets obtained from three cold storage plants in the state of Parana, Brazil

    Directory of Open Access Journals (Sweden)

    Alexandre Nobuhiro Tajiri

    2011-06-01

    Full Text Available Pisciculture is an economic activity that is steadily growing in the state of Parana, Brazil, and Nile tilapia (Oreochromis niloticus is one of the widely cultivated species in this state. Tilapia is not only a very nutritious food, but also an important indicator of environmental contamination. This study aimed to verify contamination by cadmium, copper and lead in tilapia fillets, and to compare the found values to international legislations. Were collected 135 samples of tilapia fillets, between July 2006 and May 2007, in three fish stores located in regions west and north of Paraná State. Samples of tilapia fillet were analyzed in relation to the presence of cadmiun, lead and copper, using atomic absorption spectrophotometry. Lead has not been detected in the analyses. Cadmium has been detected in three samples, on concentrations of 0.012 µg.g-1, 0.011 µg.g-1 and 0.014 µg.g-1. Copper has been detected in all fillets, and the average concentration of each cold storage plant was of 0.122 µg.g-1, 0.106 µg.g-1 and 0.153 µg.g-1. The concentrations found in this study are within the limits allowed by both the European and the Australian legislations.

  15. Genome-Wide Identification and Transcriptome-Based Expression Profiling of the Sox Gene Family in the Nile Tilapia (Oreochromis niloticus).

    Science.gov (United States)

    Wei, Ling; Yang, Chao; Tao, Wenjing; Wang, Deshou

    2016-02-23

    The Sox transcription factor family is characterized with the presence of a Sry-related high-mobility group (HMG) box and plays important roles in various biological processes in animals, including sex determination and differentiation, and the development of multiple organs. In this study, 27 Sox genes were identified in the genome of the Nile tilapia (Oreochromis niloticus), and were classified into seven groups. The members of each group of the tilapia Sox genes exhibited a relatively conserved exon-intron structure. Comparative analysis showed that the Sox gene family has undergone an expansion in tilapia and other teleost fishes following their whole genome duplication, and group K only exists in teleosts. Transcriptome-based analysis demonstrated that most of the tilapia Sox genes presented stage-specific and/or sex-dimorphic expressions during gonadal development, and six of the group B Sox genes were specifically expressed in the adult brain. Our results provide a better understanding of gene structure and spatio-temporal expression of the Sox gene family in tilapia, and will be useful for further deciphering the roles of the Sox genes during sex determination and gonadal development in teleosts.

  16. 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...

  17. The use of nile tilapia (Oreochromis niloticus) cultivation wastewater for the production of romaine lettuce (Lactuca sativa L. var. longifolia) in water recirculation system

    Science.gov (United States)

    Effendi, Hefni; Wahyuningsih, Sri; Wardiatno, Yusli

    2016-05-01

    In the recirculation aquaponic system (RAS), fish farming waste was utilized as a nutrient for plant, minimizing the water need, reducing the waste disposal into the environment, and producing the fish and plant as well. The study aimed to examine the growth of romaine lettuce (Lactuca sativa L. var. Longifolia) in aquaponic system without the addition of artificial nutrient. The nutrient relies solely on wastewater of nile tilapia (Oreochromis niloticus) cultivation circulated continuously on the aquaponic system. The results showed that tilapia weight reached 48.49 ± 3.92 g of T3 (tilapia, romaine lettuce, and inoculated bacteria), followed by T2 (tilapia and romaine lettuce) and T1 (tilapia) of 47.80 ± 1.97 and 45.89 ± 1.10 g after 35 days of experiment. Tilapia best performance in terms of growth and production occurred at T3 of 3.96 ± 0.44 g/day, 12.10 ± 0.63 %/day, 96.11 ± 1.44 % and 1.60 ± 0.07 for GR, SGR, SR, and FCR, respectively. It is also indicated by better water quality characteristic in this treatment. Romaine lettuce harvests of T2 and T3 showed no significant difference, with the final weight of 61.87 ± 5.59 and 57.74 ± 4.35 g. Overall, the integration of tilapia fish farming and romaine lettuce is potentially a promising aquaponic system for sustainable fish and horticulture plant production.

  18. Probiotic with yeast in Nile tilapia feeding during the sexual reversion period cultivated in water of tank of fish culture Probiótico com levedura na alimentação da tilápia do Nilo, durante o período de reversão sexual, cultivada em água de tanque de cultivo

    Directory of Open Access Journals (Sweden)

    Arthur dos Santos Mascioli

    2009-06-01

    Full Text Available This experiment objectified to evaluate the Saccharomyces cerevisiae as probiotic in rations for the Nile tilapia (Oreochromis niloticus during sexual reversion period. Were distributed 320 larvae in a completely randomized design with two treatments and eight replications in 25 L aquarium. The treatments consisted of a commercial ration for tilapia during sexual reversion added 0.1% of S. cerevisiae (1010 S. cerevisiae CFU/g of product and another one without the inclusion of the probiotic. Fingerlings had been counted, measured and weighed after 29 days, two fingerlings from each treatment, were randomized chosen and has their liver weighed for hepatic-somatic index determination. For microbiological studies, two samples of the water of the aquaria and one larvae of each aquarium had been carried through, in days 5 and 29 of the experiment. The number of total mesophilic bacterial did not present significant difference between the larvae of the first collection and nor between the water samples of the two carried through collections. For the second collection it had significantly higher difference in the counting for TP larvae. Any total coliforms appear in samples of water and larvae. The performance and survival were not influenced by the inclusion of Saccharomyces cerevisiae (P>0.05. Hepatic-somatic index had a significant difference (P<0.01 between treatments, being smaller to the TP than TT. The inclusion of S. cerevisiae in feed of Nile tilapia, during the period of sexual reversion, promotes intestinal colonization and reduction in hepatic-somatic index.Avaliou-se o fornecimento da Saccharomyces cerevisiae como probiótico em rações para a tilápia do Nilo (Oreochromis niloticus, durante o período de reversão sexual, criadas em água proveniente de tanque de cultivo. Foram distribuídas 320 larvas em delineamento inteiramente casualizado com dois tratamentos e oito repetições em aquários de 25L. Os tratamentos constituíram-se de

  19. Allelic variant in the anti-Mullerian hormone gene leads to autosomal and temperature-dependent sex reversal in a selected Nile tilapia line.

    Directory of Open Access Journals (Sweden)

    Stephan Wessels

    Full Text Available Owing to the demand for sustainable sex-control protocols in aquaculture, research in tilapia sex determination is gaining momentum. The mutual influence of environmental and genetic factors hampers disentangling the complex sex determination mechanism in Nile tilapia (Oreochromis niloticus. Previous linkage analyses have demonstrated quantitative trait loci for the phenotypic sex on linkage groups 1, 3, and 23. Quantitative trait loci for temperature-dependent sex reversal similarly reside on linkage group 23. The anti-Müllerian hormone gene (amh, located in this genomic region, is important for sexual fate in higher vertebrates, and shows sexually dimorphic expression in Nile tilapia. Therefore this study aimed at detecting allelic variants and marker-sex associations in the amh gene. Sequencing identified six allelic variants. A significant effect on the phenotypic sex for SNP ss831884014 (p<0.0017 was found by stepwise logistic regression. The remaining variants were not significantly associated. Functional annotation of SNP ss831884014 revealed a non-synonymous amino acid substitution in the amh protein. Consequently, a fluorescence resonance energy transfer (FRET based genotyping assay was developed and validated with a representative sample of fish. A logistic linear model confirmed a highly significant effect of the treatment and genotype on the phenotypic sex, but not for the interaction term (treatment: p<0.0001; genotype: p<0.0025. An additive genetic model proved a linear allele substitution effect of 12% in individuals from controls and groups treated at high temperature, respectively. Moreover, the effect of the genotype on the male proportion was significantly higher in groups treated at high temperature, giving 31% more males on average of the three genotypes. In addition, the groups treated at high temperature showed a positive dominance deviation (+11.4% males. In summary, marker-assisted selection for amh variant ss831884014

  20. Growth performance and metabolic efficiency in Nile tilapia (Oreochromis niloticus L.) fed on a diet containing Jatropha platyphylla kernel meal as a protein source.

    Science.gov (United States)

    Kumar, V; Akinleye, A O; Makkar, H P S; Angulo-Escalante, M A; Becker, K

    2012-02-01

    Jatropha platyphylla is available on the pacific coast from Sinaloa to Michoacán including the Nayarit and Jalisco states in Mexico. The seeds of J. platyphylla are rich in oil and protein, and the kernel meal (JPKM) prepared after oil extraction contains 70-75% crude protein (CP). Contents of essential amino acids (except lysine) are higher in JPKM than in soybean meal (SBM). Phorbol-esters, the main toxin present in most Jatropha species is absent in J. platyphylla. Heat-treated JPKM (H-JPKM) was evaluated as a protein supplement in tilapia feed and compared with that of SBM and fish meal (FM). Nile tilapia (Oreochromis niloticus L.) fingerlings (15 fish; av. body mass 13.9 ± 0.17 g) were randomly distributed in three groups with five replicates each. A 12-week experiment was conducted in a respirometer system to evaluate the growth performance, nutrient utilization and energy budget. Nile tilapia fingerlings were fed three iso-nitrogenous diets (36% CP): Control containing FM, and Jatropha and Soybean diets in which 62.5% of FM protein was replaced by H-JPKM and SBM respectively. The growth performance, feed conversion ratio, protein efficiency ratio, apparent lipid conversion and energy retention did not differ significantly among the three groups. Higher protein productive value was observed in plant protein fed groups. Average metabolic rate, energy expenditure per g protein fed and retained in the body did not differ significantly among the three groups. Conclusively, Nile tilapia fed plant protein (heated JPKM and SBM) and FM protein-based diets exhibited equal average metabolic rate which indicate that JPKM can be used as a protein source in aqua feed.

  1. Effects of vitamin E on expressions of eight microRNAs in the liver of Nile tilapia (Oreochromis niloticus).

    Science.gov (United States)

    Tang, Xue-Lian; Xu, Min-Jun; Li, Zhi-Hua; Pan, Qing; Fu, Jing-Hua

    2013-06-01

    Currently, microRNAs (miRNAs) are known to regulate cellular processes such as apoptosis, differentiation, cell cycle, and immune functions, and their expression can be altered by distinct stress conditions, such as oxidative stress. In immune systems of fish, vitamin E (VE) has a defined role as an antioxidant. In order to understand the molecular mechanism of vitamin E defending from oxidative stress, three groups of juvenile Nile tilapia (Oreochromis niloticus) (initial weight 3.25 ± 0.02 g) were fed to satiation with 3 semi-purified diets containing VE (DL-α-tocopherol acetate) of 0, 50, and 2500 mg/kg supplementation, respectively, with the expressions of eight miRNAs (miR-21, miR-223, miR-146a, miR-125b, miR-181a, miR-16, miR-155 and miR-122) in the liver of tilapia subsequently detected after 8-week growth experiment. Results showed that VE-deficient (0 mg/kg supplementation) decreased the activity of superoxide dismutase (SOD), and decreased the expressions of miR-223, miR-146a, miR-16 and miR-122, while excessive supplementation of VE (2500 mg/kg) decreased SOD activity and increased the expressions of all the eight miRNAs. The targets of the eight miRNAs were further predicated with bioinformatic approach and the possible regulating mechanisms of VE via miRNAs were analyzed. The present study confirmed that the differences in dietary VE affected expression of hepatic miRNAs which may partly demonstrate the molecular mechanism of VE, and the new idea of introducing miRNAs into research will provide the basic data for researches of molecular nutrition.

  2. Melatonin Induced Changes in Specific Growth Rate, Gonadal Maturity, Lipid and Protein Production in Nile Tilapia (Linnaeus 1758

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    Ruchi Singh

    2012-01-01

    Full Text Available We have investigated the effect of melatonin (MLT on specific growth rate (SGR% day−1, condition factor (k, gonado-somatic-index (GSI, histological structures of gonads, serum as well as gonadal protein and lipid in Nile tilapia Oreochromis niloticus. MLT treatment in the dose of 25 μg/L for three weeks reduced SGR% day−1 (0.9±0.04 as compared to control (1.23±0.026. The GSI value was significantly (p<0.05 reduced to 1.77±0.253 from control where it was 2.56±0.25. Serum protein level increased from 9.33±2.90 mg/ml (control to 11.67±1.45 mg/ml after MLT treatment while there was depressed serum triglycerides (86.16±1.078 mg/dl and cholesterol (126.66±0.88 mg/dl as compared to control values where these were 123.0±1.23 mg/dl and 132.0±1.65 mg/dl respectively. Histological structure of ovary showed small eggs of early perinucleolus stage after MLT treatment while testicular structure of control and MLT treated fish was more or less similar. It is concluded that exogenous melatonin suppressed SGR% day−1, GSI, ovarian cellular activity, protein and lipid biosynthesis, in tilapia suggesting that melatonin is useful in manipulating the gonadal maturity in fishes.

  3. The influence of stress on thyroid hormone production and peripheral deiodination in the Nile tilapia (Oreochromis niloticus).

    Science.gov (United States)

    Walpita, Chaminda N; Grommen, Sylvia V H; Darras, Veerle M; Van der Geyten, Serge

    2007-01-01

    The existence of an interaction between the adrenal/interrenal axis and the thyroidal axis has since long been established in vertebrates, including fish. However, in contrast to mammals, birds and amphibians, no effort was made in fish to expand these studies beyond the level of measuring plasma thyroid hormones. We therefore set out to examine the acute effects of a single dose of dexamethasone (DEX) on plasma thyroxine (T(4)) and 3,5,3'-triiodothyronine (T(3)) levels, as well as on the activity and mRNA expression of the different iodothyronine deiodinases in liver, gills, kidney and brain in Nile tilapia. To take into account the effect of handling stress, this treatment was compared both to a non-treated and to a saline injected group. In general, the observed changes were acute (3 and 6h) while values had returned to control levels by 24h post-injection. Only DEX administration caused an acute drop in circulating T(3) levels compared to non-treated animals, while none of the treatments affected plasma T(4) levels. This indicates that the DEX induced decrease in plasma T(3) levels was not due to a lowered thyroidal hormone production and secretion. DEX injection provoked a decrease in peripheral T(3) production capacity via a decrease in hepatic outer ring deiodination activity (both D1 and D2), whereas T(3) clearance increased by induction of the inner ring deiodinating D3 pathway in liver and in gills. Deiodination activities in kidney and brain were not affected. Effects of saline injection were only observed in liver, where D1 activity decreased and D3 activity increased as in the DEX group, but to a lesser extent. Real-time PCR showed that the changes in hepatic D3 were clearly regulated at the pretranslational level, while this was not confirmed for the other changes. Our results show that both handling stress and DEX injection acutely disturb peripheral deiodination activity in Nile tilapia. However, the effects of the long acting glucocorticoid

  4. Nile tilapia Oreochromis niloticus as a food source in advanced life support systems: Initial considerations

    Science.gov (United States)

    Gonzales, John M.; Brown, Paul B.

    2006-01-01

    Maintenance of crew health is of paramount importance for long duration space missions. Weight loss, bone and calcium loss, increased exposure to radiation and oxidative stress are critical concerns that need to be alleviated. Tilapia are currently under evaluation as a source of food and their contribution to reducing waste in advanced life support systems (ALSS). The nutritional composition of tilapia whole bodies, fillet, and carcass residues were quantitatively determined. Carbon and nitrogen free-extract percentages were similar among whole body (53.76% and 6.96%, respectively), fillets (47.06% and 6.75%, respectively), and carcass (56.36% and 7.04%, respectively) whereas percentages of N, S, and protein were highest in fillet (13.34, 1.34, and 83.37%, respectively) than whole body (9.27, 0.62, and 57.97%, respectively) and carcass (7.70, 0.39, and 48.15%, respectively). Whole body and fillet meet and/or exceeded current nutritional recommendations for protein, vitamin D, ascorbic acid, and selenium for international space station missions. Whole body appears to be a better source of lipids and n-3 fatty acids, calcium, and phosphorous than fillet. Consuming whole fish appears to optimize equivalent system mass compared to consumption of fillets. Additional research is needed to determine nutritional composition of tilapia whole body, fillet, and carcass when fed waste residues possibly encountered in an ALSS.

  5. Single or paired increase of total alkalinity and hardness of water for cultivation of Nile tilapia juveniles, Oreochromis niloticus - doi: 10.4025/actascitechnol.v34i2.12003

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    Davi de Holanda Cavalcante

    2012-03-01

    Full Text Available The present work aimed at evaluating the effects of single or paired increase of water’s total alkalinity (TA and total hardness (TH on the performance of Nile tilapia juveniles’ growth and culture water quality. Twenty five 25-L outdoor polyethylene aquaria were used to hold experimental fish (0.82 ± 0.06 g; 10 fish per aquarium for 6 weeks. There were two conditions of TA (low or high and of TH (moderate or high in the culture water, obtained by the application of different salts (CaCO3, Na2CO3 and CaSO4 upon a previously acidified water, all at the same rate. Water quality and growth performance variables were observed in each replicate. The acidification of the supply water with HCl has resulted in significantly lower final body weight (p < 0.05. Except for the Na2CO3, growth performance of tilapia has improved significantly after CaCO3 liming or CaSO4 application (p < 0.05 and no significant difference was detected between these last two fish groups (p > 0.05. It was concluded that beyond a minimum level of TA (≥ 20 mg L-1 CaCO3 and TH (≥ 20 mg L-1 CaCO3, it is also important that fish culture waters have a TH/TA ratio higher than 1.

  6. Molecular and functional characterization of peptidoglycan-recognition protein SC2 (PGRP-SC2) from Nile tilapia (Oreochromis niloticus) involved in the immune response to Streptococcus agalactiae.

    Science.gov (United States)

    Gan, Zhen; Chen, Shannan; Hou, Jing; Huo, Huijun; Zhang, Xiaolin; Ruan, Baiye; Laghari, Zubair Ahmed; Li, Li; Lu, Yishan; Nie, Pin

    2016-07-01

    PGRP-SC2, the member of PGRP family, plays an important role in regulation of innate immune response. In this paper, a PGRP-SC2 gene of Nile tilapia, Oreochromis niloticus (designated as On-PGRP-SC2) was cloned and its expression pattern under the infection of Streptococcus agalactiae was investigated. Sequence analysis showed main structural features required for amidase activity were detected in the deduced amino acid sequence of On-PGRP-SC2. In healthy tilapia, the On-PGRP-SC2 transcripts could be detected in all the examined tissues, with the most abundant expression in the muscle. When infected with S. agalactiae, there was a clear time-dependent expression pattern of On-PGRP-SC2 in the spleen, head kidney and brain. The assays for the amidase activity suggested that recombinant On-PGRP-SC2 protein had a Zn(2+)-dependent PGN-degrading activity. Moreover, our works showed that recombinant On-PGRP-SC2 protein could significantly reduce bacterial load in target organs attacked by S. agalactiae. These findings indicated that On-PGRP-SC2 may play important roles in the immune response to S. agalactiae in Nile tilapia.

  7. Survival, growth and reproduction of non-indigenous Nile tilapia, Oreochromis niloticus (Linnaeus 1758). I. Physiological capabilities in various temperatures and salinities

    Science.gov (United States)

    Schofield, Pamela J.; Peterson, Mark S.; Lowe, Michael R.; Brown-Peterson, Nancy J.; Slack, William T.

    2011-01-01

    The physiological tolerances of non-native fishes is an integral component of assessing potential invasive risk. Salinity and temperature are environmental variables that limit the spread of many non-native fishes. We hypothesised that combinations of temperature and salinity will interact to affect survival, growth, and reproduction of Nile tilapia, Oreochromis niloticus, introduced into Mississippi, USA. Tilapia withstood acute transfer from fresh water up to a salinity of 20 and survived gradual transfer up to 60 at typical summertime (30°C) temperatures. However, cold temperature (14°C) reduced survival of fish in saline waters ≥10 and increased the incidence of disease in freshwater controls. Although fish were able to equilibrate to saline waters in warm temperatures, reproductive parameters were reduced at salinities ≥30. These integrated responses suggest that Nile tilapia can invade coastal areas beyond their point of introduction. However, successful invasion is subject to two caveats: (1) wintertime survival depends on finding thermal refugia, and (2) reproduction is hampered in regions where salinities are ≥30. These data are vital to predicting the invasion of non-native fishes into coastal watersheds. This is particularly important given the predicted changes in coastal landscapes due to global climate change and sea-level rise.

  8. Ameliorative effects of Rosmarinus officinalis leaf extract and Vitamin C on cadmium-induced oxidative stress in Nile tilapia Oreochromis niloticus.

    Science.gov (United States)

    Al-Anazi, Marim Saleh; Virk, Promy; Elobeid, Mai; Siddiqui, Muzammil Iqbal

    2015-11-01

    The present studywas undertaken to assess the bioaccumulation potential of cadmium in liver, kidney, gills and muscles of freshwater fish, Nile tilapia Oreochromis niloticus and the changes in oxidative stress indices in liver and kidney with or without simultaneous treatment with waterborne vitamin C and rosemary leaf extract. Adult tilapia were divided into seven groups. Six groups were exposed to sublethal concentrations of Cd, three groups to 5 ppm, while other three to 10 ppm. Two groups from each of the Cd exposed groups were treated with Vitamin C (5ppm) and rosemary leaf extract (2.5 ppm) for a period of 21 days. Cadmium concentration in liver, kidneys and gills was significantly higher in the cadmium exposed groups being invariably high in the groups exposed to 10 ppm CdCl2.H2O.Treatment with Vitamin C and rosemary leaf extract significantly reduced cadmium concentration in comparison to non-treated Cd exposed groups. Treatment with Vitamin C and rosemary leaf extract significantly reduced oxidative stress in Cd exposed fish as evidenced from lower concentration of lipid peroxides and reduced activity of catalase and higher activity of superoxide dismutase in liver and kidney as compared to control fish. Reduction in Cd induced oxidative stress and bioaccumulation was comparable between the two antioxidant treatments, Vitamin C and rosemary leaf extract. The key findings suggest that both the antioxidants used showed ameliorative potential to reduce tissue accumulation of Cd and associated oxidative stress in fresh water fish, Nile tilapia.

  9. The Effects of Different Levels of Dietary Protein and L-Carnitine on Blood Sugar and Lipids of the New GIFT Strain of Juvenile Nile Tilapia (Oreochromis niloticus

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    Gang Chen

    2009-01-01

    Full Text Available The new GIFT (Genetically Improved Farmed Tilapia strain of Nile tilapia is a popular cultivated fish in Asia, but intensive aquaculture using nutritionally imbalanced feed has led to disorder of lipid metabolisms. An 8-week feeding experiment was conducted in order to assess the effects of different levels of L-carnitine (0, 200, 400, 600, and 800 mg/kg and dietary protein (22, 25, and 28% on blood sugar and blood lipid contents of the new juvenile GIFT strain of Nile tilapia. Results showed that dietary protein and L-carnitine had significant influences on glucose (GLU, high-density lipoprotein–cholesterol (HDL-C, total cholesterol (TC, triglyceride (TG, and low-density lipoprotein–cholesterol (LDL-C in the blood serum. The contents of GLU and HDL-C increased with the increases in dietary protein and L-carnitine levels, while the contents of TC, LDL-C, and TG decreased with the increases in dietary protein and L-carnitine levels. The interactive effect of both dietary protein and L-carnitine was most significant on GLU (p = 0.0001, followed by TG (p = 0.001, TC (p = 0.005, HDL-C (p = 0.056, and LDL-C (p = 0.109. These results suggested that high levels of dietary protein and L-carnitine supplementation reduce blood lipids and the burden of the fish liver.

  10. 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.

  11. Nile Tilapia Neu3 sialidases: molecular cloning, functional characterization and expression in Oreochromis niloticus.

    Science.gov (United States)

    Chigwechokha, Petros Kingstone; Komatsu, Masaharu; Itakura, Takao; Shiozaki, Kazuhiro

    2014-11-15

    Mammalian Neu3 is a ganglioside specific sialidase. Gangliosides are involved in various physiological events such as cell growth, differentiation and diseases. Significance of Neu3 and gangliosides is still unclear in aquaculture fish species. To gain more insights of fish Neu3 sialidases, molecular cloning and characterization were carried out in tilapia (Oreochromis niloticus). A tilapia genome-wide search for orthologues of human NEU1, NEU2, NEU3 and NEU4 yielded eight putative tilapia sialidases, five of which were neu3-like and designated as neu3a, neu3b, neu3c, neu3d and neu3e. Among five neu3 genes, neu3a, neu3d and neu3e were amplified by PCR from adult fish brain cDNA with consensus sequences of 1227bp, 1194bp and 1155bp, respectively. Multiple alignments showed conserved three Asp-boxes (SXDXGXTW), YRIP and VGPG motifs. The molecular weights for Neu3a, Neu3d and Neu3e were confirmed using immunoblotting analysis as 45.9kDa, 44.4kDa and 43.6kDa, respectively. Lysate from neu3 genes transfected HEK293 cells showed sialidase activity in Neu3a towards ganglioside mix optimally at pH4.6. Using pure gangliosides as substrates, highest sialidase activity for Neu3a was observed towards GD3 followed by GD1a and GM3, but not GM1. On the other hand, sialidase activities were not observed in Neu3d and Neu3e towards various sialoglycoconjugates. Indirect immunofluorescence showed that tilapia Neu3a and Neu3d are localized at the plasma membrane, while most Neu3e showed a cytosolic localization. RT-PCR analyses for neu3a showed significant expression in the brain, liver, and spleen tissues, while neu3d and neu3e showed different expression patterns. Based on these results, tilapia Neu3 exploration is an important step towards full understanding of a more comprehensive picture of Neu3 sub-family of proteins in fish.

  12. Lake Victoria wetlands and the ecology of the Nile Tilapia, Oreochromis Niloticus Linné

    NARCIS (Netherlands)

    Balirwa, J.S.

    1998-01-01

    The importance of LalNile tilap'a was studied. Five wetland types were defined: papyrus, reed, bulrush, hippo grass, water hyacinth. Hydrology, vegetation and distance towards open water explained the variation in abiotic and biotic factors. Over 30 fish species were ide

  13. Material Cultural Evolution: An Interview with Niles Eldredge

    Directory of Open Access Journals (Sweden)

    Belinda Barnet

    2004-01-01

    Full Text Available This article is the edited version of a discussion that took place between Professor Niles Eldredge and Belinda Barnet in March 2004. Niles is one of the world's most accomplished scientific thinkers in the field of evolutionary biology, and in this discussion he relates his ideas on the mechanisms for change in material cultural systems for a lay audience. The utility of comparing material cultural and biological systems is also discussed, and opportunities opened for further cross-disciplinary discussion between the social sciences and evolutionary biology.

  14. Transcriptome Profiling and Molecular Pathway Analysis of Genes in Association with Salinity Adaptation in Nile Tilapia Oreochromis niloticus.

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    Zhixin Xu

    Full Text Available Nile tilapia Oreochromis niloticus is a freshwater fish but can tolerate a wide range of salinities. The mechanism of salinity adaptation at the molecular level was studied using RNA-Seq to explore the molecular pathways in fish exposed to 0, 8, or 16 (practical salinity unit, psu. Based on the change of gene expressions, the differential genes unions from freshwater to saline water were classified into three categories. In the constant change category (1, steroid biosynthesis, steroid hormone biosynthesis, fat digestion and absorption, complement and coagulation cascades were significantly affected by salinity indicating the pivotal roles of sterol-related pathways in response to salinity stress. In the change-then-stable category (2, ribosomes, oxidative phosphorylation, signaling pathways for peroxisome proliferator activated receptors, and fat digestion and absorption changed significantly with increasing salinity, showing sensitivity to salinity variation in the environment and a responding threshold to salinity change. In the stable-then-change category (3, protein export, protein processing in endoplasmic reticulum, tight junction, thyroid hormone synthesis, antigen processing and presentation, glycolysis/gluconeogenesis and glycosaminoglycan biosynthesis-keratan sulfate were the significantly changed pathways, suggesting that these pathways were less sensitive to salinity variation. This study reveals fundamental mechanism of the molecular response to salinity adaptation in O. niloticus, and provides a general guidance to understand saline acclimation in O. niloticus.

  15. Comparative toxicity of copper oxide bulk and nano particles in Nile Tilapia; Oreochromis niloticus: Biochemical and oxidative stress

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    Amr A. Abdel-Khalek

    2015-10-01

    Full Text Available Nile Tilapia; Oreochromis niloticus are commonly used in the assessment of aquatic environment quality and also considered as useful bio-indicators during environmental pollution monitoring. The LC50/96 h of copper oxide (bulk & nano particles [CuO (BPs & NPs] were 2205 & 150 mg/l, respectively. Two tested concentrations of CuO (BPs & NPs were selected: the first concentration was equivalent to (1/10 (220.5 & 15 mg/l, and the second was equivalent to (1/20 (110.25 & 7.5 mg/l LC50/96 h·CuO (BPs & NPs, respectively. While serum glucose, liver function tests (AST, ALT and ALP and kidney function tests (creatinine and uric acid showed a significant increase, serum total proteins, albumin, globulin and total lipids showed a significant decrease. Both liver and gill tissues of the studied fish showed a reduction in GSH content and an elevation in MDA and GPx activities. The present study also showed an elevation in liver CAT & SOD activities when exposed to both concentrations of CuO BPs and in the case of gills when exposed to both concentrations of CuO (BPs & NPs, although activity of these enzymes showed an inhibition in the liver when exposed to both concentrations of CuO NPs. The present study investigated whether CuO NPs are more toxic than CuO BPs.

  16. Transcriptome Profiling and Molecular Pathway Analysis of Genes in Association with Salinity Adaptation in Nile Tilapia Oreochromis niloticus.

    Science.gov (United States)

    Xu, Zhixin; Gan, Lei; Li, Tongyu; Xu, Chang; Chen, Ke; Wang, Xiaodan; Qin, Jian G; Chen, Liqiao; Li, Erchao

    2015-01-01

    Nile tilapia Oreochromis niloticus is a freshwater fish but can tolerate a wide range of salinities. The mechanism of salinity adaptation at the molecular level was studied using RNA-Seq to explore the molecular pathways in fish exposed to 0, 8, or 16 (practical salinity unit, psu). Based on the change of gene expressions, the differential genes unions from freshwater to saline water were classified into three categories. In the constant change category (1), steroid biosynthesis, steroid hormone biosynthesis, fat digestion and absorption, complement and coagulation cascades were significantly affected by salinity indicating the pivotal roles of sterol-related pathways in response to salinity stress. In the change-then-stable category (2), ribosomes, oxidative phosphorylation, signaling pathways for peroxisome proliferator activated receptors, and fat digestion and absorption changed significantly with increasing salinity, showing sensitivity to salinity variation in the environment and a responding threshold to salinity change. In the stable-then-change category (3), protein export, protein processing in endoplasmic reticulum, tight junction, thyroid hormone synthesis, antigen processing and presentation, glycolysis/gluconeogenesis and glycosaminoglycan biosynthesis-keratan sulfate were the significantly changed pathways, suggesting that these pathways were less sensitive to salinity variation. This study reveals fundamental mechanism of the molecular response to salinity adaptation in O. niloticus, and provides a general guidance to understand saline acclimation in O. niloticus.

  17. Kaftas prepared with V-shaped filleting chips of the Nile tilapia (Oreochromis niloticus exposed to smoking techniques

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    Maria Luiza Rodrigues de Souza

    2015-05-01

    Full Text Available Kaftas with V-shaped filleting chips of the Nile tilapia (Oreochromis niloticus were developed and the effects of the smoking technique on the characteristics of chemical composition, microbiological, sensory and benzo(apyrene were investigated. The filleting chips were ground and filleting included condiments and bacon. Kaftas were molded, frozen and distributed in a completely randomized design with three treatments (T 1 = baked in a grid; T 2 = smoked by friction and T 3 = smoked by liquid smoke with 10 replications. The kaftas subjected to hot smoke had lower moisture content (13.97%, whereas the no-smoking kaftas had the highest content (20.49%. Kaftas with liquid smoke had high crude protein content (48.06% and ash (9.49%, whereas the ash content was different only from no-smoking kaftas (8.79%. There was no significant difference in sensory parameters, except for flavor; smoked kaftas with liquid smoke were more accepted by the judges and the worst kaftas were no-smoked kaftas. Microbiological analysis showed that kaftas developed were appropriate to feed human beings within the required standards. Chips filleting is an alternative for the development of kaftas and those subjected to liquid smoke were considered the best.

  18. Effect of propolis ethanol extract on myostatin gene expression and muscle morphometry of Nile tilapia in net cages.

    Science.gov (United States)

    Buck, E L; Mizubuti, I Y; Alfieri, A A; Otonel, R A A; Buck, L Y; Souza, F P; Prado-Calixto, O P; Poveda-Parra, A R; Alexandre Filho, L; Lopera-Barrero, N M

    2017-03-16

    Propolis can be used as growth enhancer due to its antimicrobial, antioxidant, and immune-stimulant properties, but its effects on morphometry and muscle gene expression are largely unknown. The present study evaluates the influence of propolis on muscle morphometry and myostatin gene expression in Nile tilapia (Oreochromis niloticus) bred in net cages. Reversed males (GIFT strain) with an initial weight of 170 ± 25 g were distributed in a (2 x 4) factorial scheme, with two diets (DPRO, commercial diet with 4% propolis ethanol extract and DCON, commercial diet without propolis, control) and four assessment periods (0, 35, 70, and 105 experimental days). Muscles were evaluated at each assessment period. Histomorphometric analysis classified the fiber diameters into four groups: 50 μm. RT-qPCR was performed to assess myostatin gene expression. Fibers 30 µm (30-50 and > 50 µm) at 70 days were 25.39% and 40.07% for DPRO and DCON, respectively. There was greater myostatin gene expression at 105 days, averaging 1.93 and 1.89 for DCON and DPRO, respectively, with no significant difference in any of the analyzed periods. Propolis ethanol extract did not affect the diameter of muscle fibers or the gene expression of myostatin. Future studies should describe the mechanisms of natural products' effects on muscle growth and development since these factors are highly relevant for fish production performance.

  19. NUTRITIONAL EFFECTIVENESS OF WATER HYACINTH LEAVES COMBINED WITH WHEAT BRAN AND COTTON SEED CAKE ON THE PERFORMANCE OF NILE TILAPIA (OREOCHROMIS NILOTICUS

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    H.M. ADAM SULIEMAN

    2011-11-01

    Full Text Available The aim of this study to evaluate the different levels of water hyacinth plant leaves in the diet of Nile Tilapia and their effect on growth performance so as to eliminate the water hyacinth plant from the Nile and provide a cheap food for fish. In this experiment the dried water hyacinth leaves (Eicchornia crassipse, wheat bran and cotton seed cake were used in different ratio to formulate two experimental diets (A and B. Diet (A contains 70% wheat bran, 20% cotton seed cake and 10% water hyacinth leaves, while diet (B contains 65%, 20% cottons seed cake and 15% water hyacinth leaves. These diets were fed to studied fish with 5% per their body weight for 105 days. The results of this study revealed that the diet (A has higher growth performance on studied fish than those fed on diet (B. The results of food conversion ratio (FCR, 4.04 in diet (A and food conversion ratio (FCR, 5.73 in diet (B, and the increment of growth rate in fish fed with diet (A more efficient on the growth performance of studied fish than diet (B except in the case of protein efficiency rate (PER it's found to be more in diet (A than diet (B. It was concluded that the diet (A had better growth performance than diet (B on the feeding regime of Nile tilapia (Oreochromis niloticus.

  20. Control of voluntary feed intake in fish: a role for dietary oxygen demand in Nile tilapia (Oreochromis niloticus) fed diets with different macronutrient profiles.

    Science.gov (United States)

    Saravanan, S; Geurden, I; Figueiredo-Silva, A C; Kaushik, S J; Haidar, M N; Verreth, J A J; Schrama, J W

    2012-10-28

    It has been hypothesised that, at non-limiting water oxygen conditions, voluntary feed intake (FI) in fish is limited by the maximal physiological capacity of oxygen use (i.e. an 'oxystatic control of FI in fish'). This implies that fish will adjust FI when fed diets differing in oxygen demand, resulting in identical oxygen consumption. Therefore, FI, digestible energy (DE) intake, energy balance and oxygen consumption were monitored at non-limiting water oxygen conditions in Nile tilapia fed diets with contrasting macronutrient composition. Diets were formulated in a 2 × 2 factorial design in order to create contrasts in oxygen demand: two ratios of digestible protein (DP):DE ('high' v. 'low'); and a contrast in the type of non-protein energy source ('starch' v. 'fat'). Triplicate groups of tilapia were fed each diet twice daily to satiation for 48 d. FI (g DM/kg(0·8) per d) was significantly lower (9·5%) in tilapia fed the starch diets relative to the fat diets. The DP:DE ratio affected DE intakes (P demand of these diets. Indeed, DE intakes of fish showed an inverse linear relationship with dietary oxygen demand (DOD; R 2 0·81, P theory), oxygen consumption of fish was identical among three out of the four diets. Altogether, these results demonstrate the involvement of metabolic oxygen use and DOD in the control of FI in tilapia.

  1. Pre-Slaughter Stress Affects Ryanodine Receptor Protein Gene Expression and the Water-Holding Capacity in Fillets of the Nile Tilapia.

    Directory of Open Access Journals (Sweden)

    Elenice S R Goes

    Full Text Available Current study evaluated the effect of pre-slaughter stress on serum cortisol levels, pH, colorimetry, water-holding capacity (WHC and gene expression of ryanodine receptors (RyR1 and RyR3 in the Nile tilapia. A 3x4 factorial scheme experiment was conducted comprising three densities (100, 200, 400 kg/m³ with four transportation times (60, 120, 180, and 240 minutes.Transportation times alone reduced cortisol levels up to 180 minutes, followed by increased WHC and mRNA expression, RyR1 and RyR3 (200 kg/m³ density. No effect of density x transportation time interacted on the evaluated parameters. Results provided the first evidence that pre-slaughter stress affected ryanodine gene expression receptors and, consequently, the water-holding capacity in tilapia fillets.

  2. Limit growth of ice crystals under different temperature oscillations levels in nile Tilapia

    Directory of Open Access Journals (Sweden)

    Mirko Salomon Chávez GUTIÉRREZ

    Full Text Available Abstract The degenerative effect of temperature fluctuations during storage time is a critical condition that needs to be quantitatively characterized in products where drip losses are appreciable. In this work, real storage conditions were reproduced using freezers modified to cause 3 levels of temperature fluctuation (± 0, ± 3, ± 5; ± 7 during storage of Tilapia (Oreochromis sp, at temperature of –18 °C. The fast frozen tilapia muscle (freezing cabinet was chosen to quantify the growth of ice crystals according to temperature fluctuations. The identification of crystals in the optical microscope as well as histological treatments and measurements using specific software has shown that the growth of ice crystals in the first days of storage follows an asymptote, whose final value is conditioned only by the level of temperature fluctuations regardless of initial diameter, which begins storage. It has also been found that the growth of crystals formed during rapid freezing rapidly develops according to temperature fluctuations to which the product has been subjected. This work also identified statistically significant differences in the equivalent diameter of crystals formed at the four proposed levels of temperature fluctuation with significance level of p < 0.05.

  3. Effect of repeated application of fenthion as a mosquito larvicide on Nile tilapia (Oreochromis niloticus) inhabiting selected water canals in Sri Lanka.

    Science.gov (United States)

    Jayasundara, Viranga K; Pathiratne, Asoka

    2008-04-01

    Health status of feral Nile tilapia following repeated applications of fenthion as a mosquito larvicide to selected water canals in Sri Lanka was assessed. With three spray applications of fenthion to the study sites at weekly intervals at the concentration recommended for mosquito control, condition factor and brain acetylcholinesterase activity of the fish were depressed in a time dependent manner. Prominent histopathological alterations displayed were gill hyperplasia and telangiectasis and vacoulation of hepatocytes. Observed ill health effects of fenthion on the fish demonstrate probable ecological risk to the fish populations inhabiting the water canals which receive repeated inputs of fenthion.

  4. Growth performance, feed utilization and sensory characteristics of Nile Tilapia, Oreochromis niloticus fed diets with high inclusion levels of copra meal

    DEFF Research Database (Denmark)

    Obirikorang, Kwasi Adu; Amisah, Stephen; Skov, Peter Vilhelm

    2016-01-01

    Background: The low cost and wide-availability of copra meal in many tropical countries where aquaculture is practiced have generated much interest in its potential inclusion in fish diet formulations. The present study was designed to investigate the effect of very high inclusions of autoclaved...... inclusions of copra meal did not have any significant effects on fillet sensory attributes. Conclusions: The results of this study demonstrate that it is possible to include autoclaved copra meal up to 680 g kg-1 in Nile tilapia diets without any deleterious effects on fish growth or on flesh sensory...

  5. The effect of tryptophan supplemented diets on brain serotonergic activity and plasma cortisol under undisturbed and stressed conditions in grouped-housed Nile tilapia Oreochromis niloticus

    DEFF Research Database (Denmark)

    Martins, C.I.M.; Silva, P.I.M.; Costas, B.

    2013-01-01

    Tryptophan (TRP) supplemented diets have been shown to have therapeutic effects in farmed animals including fish by modulating the activity of the neurotransmitter serotonin (5-hydroxytryptamine; 5-HT). The effects reported in fish have been obtained using individually-housed fish and include......-term supplementation with TRP supplemented diets changes brain serotonergic activity and the stress response associated with slaughter handling in grouped-housed Nile tilapia Oreochromis niloticus. Adult fish (n. =. 108, 490.6. ±. 4.0. g, 12 individuals per tank) were exposed to one of the three treatments...

  6. Dietary utilisation of protein and energy from fresh and ensiled coffee pulp by the Nile tilapia, Oreochromis niloticus

    Directory of Open Access Journals (Sweden)

    Yann Moreau

    2003-03-01

    Full Text Available Dietary protein and energy utilisation of diets containing fresh and ensiled coffee pulp were studied on 3.2 ± 0.2 g Nile tilapia for 28 days. Diets formulation and feeding were designed on the basis of daily dietary protein and energy allowance. A control diet A (100 % protein and 100 % energy allowance corresponding to 15 g CP kg-1 day-1 and 750 kJ kg-1 day-1, a low protein control diet B (80 % protein and 100 % energy allowance, two diets C and E (100 % protein and 100 % energy allowance where 20 % of protein were supplied by coffee pulp, and two diets D and F with the same amount of coffee pulp than in C and E and supplementation in non-protein energy. Inclusion of coffee pulp in the diet strongly impaired growth and feed utilisation. Silage process improved overall feed utilisation comparing to fresh coffee pulp. Results showed that fresh or ensiled coffee pulp was not a suitable feedstuff for Nile tilapia. However, better knowledge on modification occurring during silage process could allow finding the way to significantly improve nutritive value of coffee pulp by-products.Polpa de café ensilada foi utilizada na dieta calórica-protéica de Tilápia do Nilo na razão de 3.2 g ± 0,2 durante um período de 28 dias. As dietas calórico-protéica foram formuladas com base na ingestão diária permitida. Uma dieta A controle (100% de proteína e 100% da energia que corresponde a g PC/kg/dia e 750 Kj/Kg/dia, uma dieta B baixa em proteína (80% de proteína e 100% da energia, duas dietas C e E (100% de proteína e 100% da energia onde 20% da proteína foi suplementada com polpa de café e duas dietas D e F com a mesma concentração de polpa de café é prejudicial a dieta de crescimento. O processo de ensilagem melhorou sua utilização como alimento em comparação com a polpa de café fresca. Os resultados demonstraram que a polpa fresca ou ensilada não é para ser usada como alimentação de Tilápia do Nilo. Entretanto, uma melhor

  7. Salmon testes meal as a functional feed additive in fish meal and plant-protein based diets for rainbow trout(Oncorhynchus mykiss walbaum)and nile tilapia(Oreochromis niloticus L.) fry

    Science.gov (United States)

    We report that salmon testes meal (TM) produced from Alaskan seafood processing byproducts is a potential protein source for aquafeed formulations. A series of feeding trials was conducted using three different fish species; including Nile tilapia, rainbow trout, and white sturgeon at their early gr...

  8. Characterization of the POU5F1 Homologue in Nile Tilapia: From Expression Pattern to Biological Activity.

    Science.gov (United States)

    Xiaohuan, Huang; Yang, Zhao; Linyan, Liu; Zhenhua, Fan; Linyan, Zhou; Zhijian, Wang; Ling, Wei; Deshou, Wang; Jing, Wei

    2016-09-15

    POU5F1 (OCT4) is a crucial transcription factor for induction and maintenance of cellular pluripotency, as well as survival of germ cells in mammals. However, the homologues of POU5F1 in teleost fish, including zebrafish and medaka, now named Pou5f3, exhibit considerable differences in expression pattern and pluripotency-maintaining activity. To what extent the POU5F1 homologues are conserved in vertebrates has been unclear. In this study, we report that the POU5F1 homologue from the Nile tilapia (Oreochromis niloticus), OnPou5f3, displays an expression pattern and biological activity somewhat different from those in zebrafish or medaka. The expression of Onpou5f3 at both mRNA and protein levels was abundant in early development embryos until blastula stages, barely detectable as proceeding, and then displayed a transiently strong expression domain in the brain region during neurula stages similar to zebrafish but not medaka. Afterward, OnPou5f3 appeared as germline-restricted (including primordial germ cells and female and male gonad germ cells) expression just like medaka. Notably, OnPou5f3 depletion through morpholino oligos caused blastula blockage or lethality and failure of survival and proliferation of blastula cell-derived cells. These findings indicate that equivalent POU5F1-like expression and activity of Pou5f3 might be conserved accompanying with species-specific expression pattern during evolution. Our study provides insight into the evolutionary conservation of the POU5F1 homologues across vertebrates.

  9. Physiological, biochemical and histometric responses of Nile tilapia (Oreochromis niloticus L.) by dietary organic chromium (chromium picolinate) supplementation.

    Science.gov (United States)

    Mehrim, Ahmed I

    2014-05-01

    Chromium has been recognized as a new and important micro-nutrient, essential for both human and animal nutrition. This study was conducted to evaluate the appropriateness and/or the use of safety level of dietary chromium picolinate (Cr-Pic), and its effects on the physiological responses, the histometric characteristics, and the chemical analysis of dorsal muscles of mono-sex Nile tilapia, Oreochromis niloticus. A total of 420 fingerlings (28.00 ± 0.96 g) were randomly distributed into 21 fiberglass tanks representing seven treatments at a rate of 20 fish m(-3). The control fish group (T1) was fed a Cr-Pic free basal diet. Other fish groups were fed the basal diet supplemented with 200 (T2), 400 (T3), 600 (T4), 800 (T5), 1000 (T6) and 1200 μg Cr-Pic kg(-1) diet (T7). Diets were offered to fish at a feeding rate of 3% of life body weight for 12 weeks. Results revealed that blood hematological parameters (hemoglobin, red blood cells, packed cell volume, mean corpuscular hemoglobin concentration, blood platelets, and white blood cells lymphocytes); serum biochemical measurements (total testosterone, high density lipoprotein, total protein, albumin, and globulin); and the dry matter and crude protein of the fish dorsal muscles all have significantly increased (P ⩽ 0.05) in the T3 treatment compared with the other treatments. Meanwhile, no significant differences were found among all treatments with regard to the histometric characteristics. It can be concluded that Cr-Pic at 400 μg kg(-1) diet (T3) seems to be the most appropriate level for O. niloticus fingerlings.

  10. Physiological, biochemical and histometric responses of Nile tilapia (Oreochromis niloticus L. by dietary organic chromium (chromium picolinate supplementation

    Directory of Open Access Journals (Sweden)

    Ahmed I. Mehrim

    2014-05-01

    Full Text Available Chromium has been recognized as a new and important micro-nutrient, essential for both human and animal nutrition. This study was conducted to evaluate the appropriateness and/or the use of safety level of dietary chromium picolinate (Cr-Pic, and its effects on the physiological responses, the histometric characteristics, and the chemical analysis of dorsal muscles of mono-sex Nile tilapia, Oreochromis niloticus. A total of 420 fingerlings (28.00 ± 0.96 g were randomly distributed into 21 fiberglass tanks representing seven treatments at a rate of 20 fish m−3. The control fish group (T1 was fed a Cr-Pic free basal diet. Other fish groups were fed the basal diet supplemented with 200 (T2, 400 (T3, 600 (T4, 800 (T5, 1000 (T6 and 1200 μg Cr-Pic kg−1 diet (T7. Diets were offered to fish at a feeding rate of 3% of life body weight for 12 weeks. Results revealed that blood hematological parameters (hemoglobin, red blood cells, packed cell volume, mean corpuscular hemoglobin concentration, blood platelets, and white blood cells lymphocytes; serum biochemical measurements (total testosterone, high density lipoprotein, total protein, albumin, and globulin; and the dry matter and crude protein of the fish dorsal muscles all have significantly increased (P ⩽ 0.05 in the T3 treatment compared with the other treatments. Meanwhile, no significant differences were found among all treatments with regard to the histometric characteristics. It can be concluded that Cr-Pic at 400 μg kg−1 diet (T3 seems to be the most appropriate level for O. niloticus fingerlings.

  11. Mapping and Validation of the Major Sex-Determining Region in Nile Tilapia (Oreochromis niloticus L.) Using RAD Sequencing

    Science.gov (United States)

    Khan, Mohd G. Q.; Taggart, John B.; Gharbi, Karim; McAndrew, Brendan J.; Penman, David J.

    2013-01-01

    Sex in Oreochromis niloticus (Nile tilapia) is principally determined by an XX/XY locus but other genetic and environmental factors also influence sex ratio. Restriction Associated DNA (RAD) sequencing was used in two families derived from crossing XY males with females from an isogenic clonal line, in order to identify Single Nucleotide Polymorphisms (SNPs) and map the sex-determining region(s). We constructed a linkage map with 3,802 SNPs, which corresponded to 3,280 informative markers, and identified a major sex-determining region on linkage group 1, explaining nearly 96% of the phenotypic variance. This sex-determining region was mapped in a 2 cM interval, corresponding to approximately 1.2 Mb in the O. niloticus draft genome. In order to validate this, a diverse family (4 families; 96 individuals in total) and population (40 broodstock individuals) test panel were genotyped for five of the SNPs showing the highest association with phenotypic sex. From the expanded data set, SNPs Oni23063 and Oni28137 showed the highest association, which persisted both in the case of family and population data. Across the entire dataset all females were found to be homozygous for these two SNPs. Males were heterozygous, with the exception of five individuals in the population and two in the family dataset. These fish possessed the homozygous genotype expected of females. Progeny sex ratios (over 95% females) from two of the males with the “female” genotype indicated that they were neomales (XX males). Sex reversal induced by elevated temperature during sexual differentiation also resulted in phenotypic males with the “female” genotype. This study narrows down the region containing the main sex-determining locus, and provides genetic markers tightly linked to this locus, with an association that persisted across the population. These markers will be of use in refining the production of genetically male O. niloticus for aquaculture. PMID:23874606

  12. Performance of Nile tilapia Oreochromis niloticus fingerlings in a hyper-intensive recirculating aquaculture system with low water exchange

    Directory of Open Access Journals (Sweden)

    M Gullian-Klanian

    2013-03-01

    Full Text Available The aim of this paper was evaluate the performance of Nile tilapia fingerlings (Oreochromis niloticus raised at hyper intensive stocking density in a recirculating aquaculture system (RAS with minimum water replacing. The experimental system was performed in a single-batch nursery system to obtain 50 g fish size in 60 days. Fish (2.07 ± 0.04 g were stocked in triplicate at 400 (T1, 500 (T2 and 600 (T3 fish m-3 (0.84, 1.05, 1.22 kg m-3. RAS functioned with 12,000 L of recirculating water and 252 L day-1of water replacing (2.1% daily. The efficiency of the biofilter for removing the total ammonia nitrogen (TAN was 48 ± 12.5 mg L-1. Stocking density did not affect significantly the survival (89.5 to 93.6%. The growth rate of T1 (0.96 g day-1; 5.01% day-1 and T2 (0.92 g day-1; 4.95 % day-1 was significantly higher than T3 (0.83 g day-1; 4.80% day-1. The specific growth rate (SGR of T1 was 41% influenced by temperature. For T2 and T3 the SGR were influenced by the variation of dissolved oxygen (DO that explained 47 and 44% of the fish weight variation, respectively. The SGR from T3 was also affected by the concentration of ammonia nitrogen (31%. The high stocking density affected the overall size of fish and the size homogeneity, but had no negative effect on the length-weight relationship (L-W. Data support the conclusion that fingerling stocked at 400 and 500 fish m-3 shows high performance during 9-weeks when the biomass not exceed 37 kg m-3. At this time fish have reached the desired final nursery weight (50 g for transfer to grow-out facilities.

  13. Effects of Cordyceps militaris spent mushroom substrate and Lactobacillus plantarum on mucosal, serum immunology and growth performance of Nile tilapia (Oreochromis niloticus).

    Science.gov (United States)

    Van Doan, Hien; Hoseinifar, Seyed Hossein; Dawood, Mahmoud A O; Chitmanat, Chanagun; Tayyamath, Khambou

    2017-09-04

    An 8-weeks feeding trial was performed to investigate the possible effects of supplementation of Nile tilapia diet with Cordyceps militaris spent mushroom substrate (SMS) single or combined with Lactobacillus plantarum on immune parameters and growth performance. For this aim, Nile tilapia fingerlings were fed with four experimental diets namely: Diet 1 (0 - control), Diet 2 (10 g kg(-1) SMS), Diet 3 (10(8) CFU g(-1)L. plantarum), and Diet 4 (10 g kg(-1) SMS + 10(8) CFU g(-1)L. plantarum). At the end of feeding trial, skin mucus parameters, serum immune parameters, and growth performance were measured. The results indicated that supplementations SMS + L. plantarum or/and resulted in a significant increase in skin mucus lysozyme and peroxidase activities compared with the control group after 8 weeks of feeding trial (P  0.05). The FCR was significantly lower in fish fed 10 g kg(-1) SMS + 10(8) CFU g(-1)L. plantarum than in other groups, while control group presented the highest values (P < 0.05). The present results suggested that the combination of these natural substances could be considered as potential feed-additives for aquaculture farmed fish. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Attenuated virulence of pigment-producing mutant of Aeromonas veronii bv. sobria in HeLa cells and Nile tilapia (Oreochromis niloticus

    Directory of Open Access Journals (Sweden)

    Said K. Abolghait

    2013-06-01

    Full Text Available Aeromonas species are potential water/foodborne pathogens, whereas Aeromonas veronii bv. sobria is one of the most virulent species to human and fish. Most current experimental evidence has publicized that suicide plasmid dependent IS1-element untargeted integration into A. veronii bv. sobria ATCC 9071T strain was recently used to generate brown pigment-producing and spontaneous pelleting (BP+SP+ mutant. Current study was conducted to compare virulence of wild-type ATCC 9071T strain and its BP+SP+ mutant with respect to cytotoxicity in HeLa cells and lethality in Nile tilapia. It was found that the cytotoxicity of wild-type ATCC 9071T strain to HeLa cells has reached 75% versus 50% for the cytotoxicity of BP+SP+ mutant. Further, the median lethal dose (LD50 of wild-type ATCC 9071T strain in Nile tilapia was 8.25 Log10 colony-forming units (CFU/ml, compared to 9.16 Log10 CFU/ml for the LD50 of BP+SP+ mutant. Thus, current study supports the notion that non pigment-producing Aeromonas strains are more virulent than pigment-producing ones.

  15. P-glycoprotein and CYP1A protein expression patterns in Nile tilapia (Oreochromis niloticus) tissues after waterborne exposure to benzo(a)pyrene (BaP).

    Science.gov (United States)

    Costa, Joana; Reis-Henriques, Maria Armanda; Wilson, Jonathan M; Ferreira, Marta

    2013-09-01

    The protein levels and tissue distribution patterns of P-glycoprotein (Pgp) and cytochrome P450 (CYP1A) were investigated in Nile tilapia (Oreochromis niloticus) after waterborne exposure to different benzo(a)pyrene (BaP) concentrations, using immunochemical approaches. The Pgp mammalian monoclonal antibody (mAb) C219 cross reacted with a ∼170kDa protein, almost exclusively localized to the bile canaliculi, while probing with the Pgp mammalian mAb C494, resulted in a positive reaction in liver, gills and intestine of Nile tilapia and covered a wider set of cell types. Levels of Pgp expression were not altered after in vivo exposure to BaP. CYP1A, detected with the mAb C10-7, reacted positively in liver, gills and intestine and followed a BaP dose-dependent fold induction. Taken together, these results indicate that CYP1A is involved in BaP metabolism in liver, gills and intestine, however, further studies are needed to elucidate the possible interaction of the efflux protein Pgp with BaP and/or its metabolites.

  16. The effects of dietary kefir and low molecular weight sodium alginate on serum immune parameters, resistance against Streptococcus agalactiae and growth performance in Nile tilapia (Oreochromis niloticus).

    Science.gov (United States)

    Van Doan, Hien; Hoseinifar, Seyed Hossein; Tapingkae, Wanaporn; Khamtavee, Pimporn

    2017-03-01

    The present study evaluates the effects of dietary kefir and low molecular weight sodium alginate (LWMSA) (singular or combined) on non-specific immune response, disease resistance and growth performance of Nile tilapia (Oreochromis niloticus). Fish with average weight of 18.60 ± 0.04 g were supplied and randomly stocked in sixteen glass tanks (150 L) at density of 20 fish per tank. Fish were fed experimental diets as follows: 0 g kg(-1) LMWSA (Control, Diet 1), 10 g kg(-1) LMWSA (Diet 2), 40 g kg(-1) kefir (Diet 3), and 10 g kg(-1) LMWSA + 40 g kg(-1) kefir (Diet 4) for 50 days. At the end of the feeding trial, serum lysozyme (SL), phagocytosis (PI), respiratory burst (RB), and alternative complement (ACH50) activities as well as growth performance were measured. Singular and combined administration of kefir and low molecular weight sodium alginate (LMWSA) significantly increased serum SL, PI, RB, and ACH50 activities compared control group (P kefir + LMWSA) (P kefir and LMWSA can be considered for improving immune response, disease resistance and growth performance of Nile tilapia. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. Gene delivery to Nile tilapia cells for transgenesis and the role of PI3K-c2α in angiogenesis

    Science.gov (United States)

    Tonelli, Fernanda Maria Policarpo; Lacerda, Samyra Maria dos Santos Nassif; Procópio, Marcela Santos; Lemos, Breno Luiz Sales; de França, Luiz Renato; Resende, Rodrigo Ribeiro

    2017-01-01

    Microinjection is commonly performed to achieve fish transgenesis; however, due to difficulties associated with this technique, new strategies are being developed. Here we evaluate the potential of lentiviral particles to genetically modify Nile tilapia cells to achieve transgenesis using three different approaches: spermatogonial stem cell (SSC) genetic modification and transplantation (SC), in vivo transduction of gametes (GT), and fertilised egg transduction (ET). The SC protocol using larvae generates animals with sustained production of modified sperm (80% of animals with 77% maximum sperm fluorescence [MSF]), but is a time-consuming protocol (sexual maturity in Nile tilapia is achieved at 6 months of age). GT is a faster technique, but the modified gamete production is temporary (70% of animals with 52% MSF). ET is an easier way to obtain mosaic transgenic animals compared to microinjection of eggs, but non-site-directed integration in the fish genome can be a problem. In this study, PI3Kc2α gene disruption impaired development during the embryo stage and caused premature death. The manipulator should choose a technique based on the time available for transgenic obtainment and if this generation is required to be continuous or not. PMID:28317860

  18. The use of lactic acid bacteria isolated from intestinal tract of Nile tilapia (Oreochromis niloticus, as growth promoters in fish fed low protein diets

    Directory of Open Access Journals (Sweden)

    Maurilio Lara-Flores

    2013-07-01

    Full Text Available In this study, the effect as growth promoter of five lactic acid strains (Enterococcus faecium, E. durans, Leuconostoc sp., Streptococcus sp. I and Streptococcus sp. II, isolated from intestinal tract of Nile tilapia (Oreochromis niloticus, was evaluated. Eight isocaloric diets were formulated: one containing 40% of protein as positive control, and seven with 27% protein. Five diets with 27% protein were supplemented with one of the isolated lactic acid bacteria in a concentration of 2.5x10(6 cfu g-1 of diet. A commercial probiotic based on S. faecium and Lactobacillus acidophilus was added at the same concentration to one 27% protein diet as a comparative diet, and the last diet was not supplemented with bacteria (negative control. Tilapia fry (280 mg basal weight stocked in 15 L aquaria at a density of two per liter were fed for 12 weeks with experimental diets. Results showed that fry fed with native bacteria supplemented diets presented significantly higher growth and feeding performance than those fed with control diet. Treatment with Streptococcus sp. I isolated from the intestine of Tilapia produced the best growth and feeding efficiency, suggesting that this bacteria is an appropriate native growth promoter.

  19. Replacement of Fishmeal by Single Cell Protein Derived from Yeast Grown on Date (Phoenix dactylifera) Industry Waste in the Diet of Nile Tilapia (Oreochromis niloticus) Fingerlings

    KAUST Repository

    Al-Hafedh, Yousef S.

    2013-10-02

    Isonitrogenous and isocaloric diets (32% protein, 4.3 Kcal/g) were formulated to replace fishmeal by single cell protein (SCP) from two yeasts, Saccharomyces cerevisiae and Candida utilis, grown on date (Phoenix dactylifera) processing waste in diets for two size groups (avg 15.39 g and 25.14 g) of juvenile Nile tilapia (Oreochromis niloticus). A control diet (T1) with fishmeal and six experimental diets (S1, S2, and S3 with S. cerevisiae, and C1, C2, and C3 with C. utilis) each containing 11.6%, 23.2%, and 34.2% yeast as SCP were prepared to replace 25%, 50%, and 75% of fishmeal, respectively. Tilapia fed on the control and experimental diets (S1, S2, C1, C2) with 25% and 50% replacement of fishmeal showed better growth and feed utilization. Fish fed on diets S3 and C3 (75% fishmeal replacement) had significantly (p < 0.05) poorer growth suggesting that yeast SCP can replace up to 50% of fishmeal in juvenile tilapia diets. © 2013 Copyright Taylor and Francis Group, LLC.

  20. Effect of N-acetyl cysteine and glycine supplementation on growth performance, glutathione synthesis, anti-oxidative and immune ability of Nile tilapia, Oreochromis niloticus.

    Science.gov (United States)

    Xie, Shiwei; Zhou, Weiwen; Tian, Lixia; Niu, Jin; Liu, Yongjian

    2016-08-01

    An 8-week feeding trial was conducted to evaluate the effect of N-acetyl cysteine (NAC) and glycine supplementation on growth performance, glutathione (GSH) synthesis, anti-oxidative and immune ability of Nile tilapia, Oreochromis niloticus. Four practical diets were formulated, control, control +0.2% NAC, control +0.5% glycine, control +0.2% NAC +0.5% glycine. Each diet was randomly assigned to quadruplicate groups of 30 fish (approximately 9.5 g). The weight gain and specific growth rate were significantly increased with the supplementation of NAC and glycine. While they had no effect on feed efficiency feed intake and survival. Glutathion peroxidase (GPx) was increased by NAC and γ-glutamine cysteine synthase (γ-GCS) in plasma were increased by glycine. After the feeding trail, fish were challenged by Streptococcus iniae, fish fed the diet supplemented with NAC obtained significantly higher survival rate after 72 h challenge test. NAC also decreased malonaldehyde (MDA) in liver, increased glutathione S-transferase (GST) activity in plasma, up-regulated mRNA expression of Superoxide dismutase (SOD) and GPx in liver and headkidney. Dietary supplementation of glycine increased the anti-oxidative ability of tilapia through increase anti-oxidative enzyme activity (SOD, glutathione reductase, myeloperoxidase) and up-regulate anti-oxidative gene expression (SOD). Immune ability only enhanced by the supplementation of NAC through increased interleukin-1β (IL-1β) mRNA expression. These results clearly indicated that the supplementation of NAC and glycine can significantly improve the growth performance of tilapia, and NAC also enhance the anti-oxidative and immune capacity of tilapia, glycine could only enhance the anti-oxidative ability.

  1. 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...

  2. Effects of dietary acidifiers on growth, hematology, immune response and disease resistance of Nile tilapia, Oreochromis niloticus.

    Science.gov (United States)

    Reda, Rasha M; Mahmoud, Rania; Selim, Khaled M; El-Araby, Iman E

    2016-03-01

    between G1 and G2 after 30 d. The lowest immune parameters were recorded in G4. After 30 d, the highest expression of interleukin-1β and tumor necrosis factor-alpha in the liver and kidney were found in G3. The best protection against challenged Aeromonas sobria was in G3, followed by G2 and G4. Dietary supplementation with a combination of formic acid, propionic acid and calcium propionate improves the performance of Nile tilapia.

  3. Ecotoxicity of natural insecticide based on tobacco plant extract and hematological effects on the Nile tilapia (Oreochromis niloticus. Ecotoxicity and hematological effects of a natural insecticide based on tobacco (Nicotiana tabacum extract on Nile tilapia (Oreochromis niloticus - doi: 10.4025/actascibiolsci.v35i2.14131

    Directory of Open Access Journals (Sweden)

    Marisa Narciso Fernandes

    2013-05-01

    Full Text Available Natural insecticides derived from plant extracts have been used as an alternative to synthetic products in order to reduce environmental contamination. The present study aimed to examine the effects of Fumydro®, a natural insecticide based in the tobacco plant Nicotiana tabacum, on the Nile tilapia (Oreochromis niloticus by determining the 48-h LC50 and evaluating their effects on hematological variables. Adult specimens of O. niloticus were exposed to four Fumydro® concentrations (200, 300, 400 and 500 μL L-1. The 48-h LC50 of Fumydro® was determined as 370 ± 50 μL L-1. Surviving fish showed increasing in the red blood cells, hemoglobin concentration, mean corpuscular hemoglobin and mean corpuscular hemoglobin concentration. The thrombocytes did not change but the percentage of neutrophils increased. These results indicated that the insecticide Fumydro® is toxic to Nile tilapia and the changes of the erythrocyte variables suggested hypoxemia induction with low effect on the immune system.Natural insecticides from plant extracts represent an alternative to the highly toxic synthetic products in order to reduce environmental contamination; however some might also be toxic for non-target organisms. The present study determined the 50% lethal concentration (48h; LC50 for adults Nile tilapia (Oreochromis niloticus exposed to the natural insecticide Fumydro®, based on the tobacco plant (Nicotiana tabacum, and evaluated its effect on hematological variables. After preliminary tests, adult specimens of O. niloticus were exposed to four Fumydro® concentrations (200, 300, 400 and 500 μL L-1. The 48h; LC50 of Fumydro® was determined at 370 ± 50 μL L-1. The surviving fish after exposure to Fumydro® showed an increase in the number of red blood cells, hemoglobin concentration, mean corpuscular hemoglobin and mean corpuscular hemoglobin concentration. The number of thrombocytes and leukocytes has not changed, unlike the differential leukocyte

  4. Tilapia cage culture and the dissolved oxygen trends in Sampaloc Lake, the Philippines.

    Science.gov (United States)

    Santiago, A E; Arcilla, R P

    1993-02-01

    The 28-hectare tilapia cage culture that occupied the 104-hectare Sampaloc Lake, a crater lake, shifted to intensive method in 1986 when tilapia growth slowed done at the beginning of 1982. Thus, commercial feeds became the main source of allochthonous organic matter in the lake. Total feeds given annually for the 28-hectare cage culture at 3 croppings per year amounted to 5250 tons. At feed conversion ratio of 1 : 2 a significant portion of the feeds given ended as organic wastes in the lake. In 1988, tilapia cage operators began experiencing their worst occurrences of fishkill, worth millions of pesos. An assessment of the dissolved oxygen condition of Sampaloc lake in late 1989, 1990 and mid-1991 showed ominous trends which might adversely affect the use of Sampaloc lake for fishery.

  5. Influence of water temperature and waterborne cadmium toxicity on growth performance and metallothionein-cadmium distribution in different organs of Nile tilapia, Oreochromis niloticus (L.).

    Science.gov (United States)

    Abdel-Tawwab, Mohsen; Wafeek, Mohammed

    2014-10-01

    Cadmium (Cd) is believed to be one of the most abundant and ubiquitously distributed toxins in the aquatic system. This metal is released to the aquatic environment from both anthropogenic sources, such as industrial, agricultural and urban effluents as well as natural sources, such as rocks and soils. Otherwise, the temperature increase of water bodies, which has been observed due to global climatic changes, has been shown to increase Cd toxicity for several aquatic animal species including fish. In the present study, Nile tilapia, Oreochromis niloticus (L.), (26.0 ± 0.38 g) were reared at 20, 24, 28, or 32 °C and exposed to 0.0 or 0.5mg Cd/L for 8 weeks to investigate effects of water temperature, Cd toxicity and their interaction on fish performance as well as metallothionein (MT) and Cd distribution in different fish organs. It was found that fish reared in Cd-free group at 28 °C showed the optimum growth and feed intake, while Cd-exposed fish showed low growth and feed intake irrespective to water temperature. A synergetic relationship between water temperature and Cd toxicity was observed where Cd toxicity increased as water temperature increased and the worse growth was obtained in Cd-exposed fish reared at 32 °C. Additionally, the highest Cd residues in different fish organs were detected in Cd-exposed fish reared at 32 °C. Similarly, MT concentrations in different fish organs increased as water temperature increased especially in Cd-exposed fish groups. A high positive correlation between MT and Cd concentrations in fish organs was detected. The distribution of MT and Cd levels was in the order of liver>kidney>gills>muscles. The present study revealed that the optimum water temperature suitable for Nile tilapia growth is 28 °C. Additionally, Cd exposure had a deteriorate effect on the growth and health of Nile tilapia. This hazardous effect increased as water temperature increased. Further, liver and kidney were the prime sites of Cd accumulation

  6. Genetic studies on sex determination and colouration in Nile tilapia (Oreochromis niloticus L.)

    Energy Technology Data Exchange (ETDEWEB)

    Karayuecel, I

    1999-05-01

    The present study was undertaken to investigate colour and sex determination mechanisms through the application of androgenesis, gynogenesis and controlled breeding programme with the objective of producing all red males in O. niloticus. The highest yield of androgenetic haploid to pigmentation stage was 24.6{+-}3.5% (relative to controls) with optimal UV irradiation dose of 450JM{sup -2} for 5 minutes. The highest survival rate of diploid androgens was 0.07{+-}0.07% (relative to controls) to yolk sac stage using a heat shock of 42.5 deg. C for 3 minutes 30 seconds applied at 25 minutes after fertilisation. All paternal inheritance of diploid androgenetic tilapia was verified using DNA fingerprinting. The mean recombination frequency of the red skin colour gene in meiotic gynogens was 0.12{+-}0.04. All maternal inheritance of meiotic gynogens was verified using the isozyme locus ADA*. Analyses of sex ratios of meiotic gynogens suggested that male progenies were produced by an epistatic sex determining locus (SDL-2 with two alleles SR and sr) causing female to male sex reversal in the homozygous phase (srsr) but with limited penetrance. A close linkage was found between a sex determining locus (SDL-2) and the red gene. No significant difference was found between colour genotypes (namely homozygous red, heterozygous red and wild type) in terms of total fecundity, ISI (inter spawning interval), egg size and survival rate. Overall mean ISI was 26.3{+-}1.0 days. Mean total fecundity was 1096 eggs. Fecundity varied over successive spawns but this variation did not appear to be related to spawning periodicity. Hormonal and thermal feminization were compared on all YY male progeny of O. niloticus. While similar female percentages of 32.0{+-}5.2 and 33.8{+-}1.5% were produced, significantly higher intersex percentages of 18.5{+-}2.5 and 1.6{+-}0.8 were observed in heat and DES treated groups, respectively. Heat treatment groups showed the lowest survival rate of 62

  7. 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),

  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. Effects of dietary levels of carbohydrate, lipid, phosphorus and zinc on the growth, feed conversion and protein efficiency ratio of Nile tilapia ( Oreochromis niloticus)

    Science.gov (United States)

    Li, Zhongjie; Lei, Wu; Yang, Yunxia; Ye, Jun

    1993-09-01

    A 54-day feeding experiment was conducted on juvenile Nile tilapia using isonitrogenous, isocaloric semipurified diets. The carbohydrate content in the diet was 9%, 32% and 50%; the corresponding lipid content was 22.2%, 12%, and 4%. The diets were supplemented with 0.85% or 1.5% phosphorus and 40 mg/kg or 100 mg/kg zinc. The experiment was carried out in flow-through aquaria using dechlorinated tap water at 23 26°C. The experiment showed that the increase of the carbohydrate content in the diets resulted in a 43 249% increase in weight gain, a 27 59% decrease in feed conversion ratio, and a 65 121% increase in protein efficiency ratio. In fish fed diets containing 36 50% carbohydrate, an increase in supplemented phosphorus to 1.5% greatly increased the weight gain. On the contrary, a high content of supplemented zinc (100 mg/kg) inhibited growth and increased feed conversion ratio.

  10. Assessment and control of an invasive aquaculture species: An update on Nile tilapia (Oreochromis niloticus) in coastal Mississippi after Hurricane Katrina

    Science.gov (United States)

    Schofield, Pamela J.; Slack, W. Todd; Peterson, Mark S.; Gregoire, Denise R.

    2007-01-01

    We provide information about the effects of Hurricane Katrina on populations of an invasive fish, the Nile tilapia (Oreochromis niloticus) in southern Mississippi. By resampling areas surveyed before the storm, we attempted to determine whether the species expanded its range by moving with storm-related floods. Additionally, we used rotenone to eradicate individuals of this species at a hurricane-damaged aquaculture facility on the Mississippi coast. Although our survey was limited geographically, we did not find the species to occur beyond the aquaculture facility, other than in an adjacent bayou. Our rotenone treatment of the facility appeared effective with only a single O. niloticus being collected six weeks after the treatment. To reduce the spread of O. niloticus in the southeastern U.S., it is important to continue to control feral populations, work to eliminate vectors for dispersal, and continue monitoring their distribution.

  11. In vitro evaluation of the efficacy of hemodialysate (Solcoseryl® as a wound healing agent in Nile tilapia (Oreochromis niloticus

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    A.E. Eissa

    2013-12-01

    Full Text Available Skin wounds are the most prevalent daily affections intruding fishes in an aquaculture facility. Such skin affections are considered to be the most common portals of entry for disease agents affecting fishes. This persistent phenomenon necessitates a comprehensive search for an efficient healing therapy to combat the ongoing dermal damage and its pathological consequences. In the current study, the core hypothesis has been vigorously tested through the experimental application of hemodialysate (Solcoseryl® solution in several exposure methods including bath, intraperitoneal (I.P., intramuscular (I.M., and local infiltration routes. All tested routes were capable of inducing different degrees of healing in Nile tilapia (Oreochromis niloticus. The core hypothesis of the current research has been experimentally accomplished through assessing the resultant healing degrees based on both gross as well as tissue alteration dynamics among total of 5 experimental groups. Each group consisted of 10 fishes/aquarium. The swift tissue healing of the induced wounds in Nile tilapia were completely achieved 4 days post I.M. injection of the Solcoseryl® solution (10 μl/50 g fish as a single dose with an excellent healing grade (+++++. However, bath treatment (1 ml/Lwater as a single dose and local infiltration (10 μl/50 g fish as a single dose have proved to be second on the race (complete healing was achieved 6 days post treatment with very good grade (+++. This study demonstrates the clinical value of fish models in establishment of new approach for combating prevalent invasive skin affections in aquaculture.

  12. Combined administration of low molecular weight sodium alginate boosted immunomodulatory, disease resistance and growth enhancing effects of Lactobacillus plantarum in Nile tilapia (Oreochromis niloticus).

    Science.gov (United States)

    Van Doan, Hien; Hoseinifar, Seyed Hossein; Tapingkae, Wanaporn; Tongsiri, Sudaporn; Khamtavee, Pimporn

    2016-11-01

    The present study investigates the effects of combined or singular administration of low molecular weight sodium alginate (LWMSA) and Lactobacillus plantarum on innate immune response, disease resistance and growth performance of Nile tilapia (Oreochromis niloticus). Three hundred and twenty fish were supplied and randomly stocked in sixteen glass tanks (150 L) assigned to four treatments as follows: 0 g kg(-1) LMWSA (Control, Diet 1), 10 g kg(-1) LMWSA (Diet 2), 10(8) CFU g(-1)L. plantarum (Diet 3), and 10 g kg(-1) LMWSA + 10(8) CFU g(-1)L. plantarum (Diet 4). Following 30 and 60 days of the feeding trial, serum lysozyme, phagocytosis, respiratory burst and alternative complement activities as well as growth performance parameters (specific growth rate, feed conversion ratio) were measured. Serum lysozyme, phagocytosis, respiratory burst, and alternative complement activities of fish were significantly stimulated by both LMWSA and L. plantarum diets, however, the highest innate immune response were observed in fish fed synbiotic diet. At the end of the experiment, eight fish per replication were randomly selected for a challenge test against Streptococcus agalactiae. The survival rate of the fish fed supplemented diets was significantly greater than the control treatment and the highest post challenge survival rate was observed in synbiotic diet. Furthermore, SGR and FCR were significantly improved in fish fed supplemented diets after 60 days and the highest growth performance was observed in fish fed synbiotic diet. These results suggest combined LMWSA and L. plantarum can be considered as a promising immunostimulant and growth enhancer in Nile tilapia diet.

  13. Atypical feminized male’s agonistic behavior relative to males and females of Nile tilapia (Oreochromis niloticus L.

    Directory of Open Access Journals (Sweden)

    Felipe Becerril-Morales

    2015-11-01

    Full Text Available Early maturity during tilapia culture is a recurring problem. To avoid this, a series of techniques have been developed, including the production of YY-males. This technique involves the use of hormones to produce phenotypic females (XY genotype. However, incomplete transformations are frequently observed and the produced atypical feminized males (AFM could display an ambiguity in the phenotypic expression of behavioral patterns. The aim of this study was to measure the frequency and intensity of aggressive behavior as well as the role that initial residence plays when involving three phenotypes (males, females and AFM. The experiment consisted of three stages. Resident fish were AFM in the first stage, males in the second and females in the third. In each stage the resident fish confronted males, females and AFM acting as intruders. Aggressive behavior was exercised more frequently by resident fish. Intersexual confrontations showed higher levels of aggression compared to intrasexual confrontations. The frequency of confrontations was not significantly different in confrontations involving AFM, however, differences were observed in intensity of aggression. It is possible that an incomplete transformation at physiological level could be responsible for an inaccurate decoding of signal during confrontations.

  14. Effects of dietary live and heat-inactive baker's yeast on growth, gut health, and disease resistance of Nile tilapia under high rearing density.

    Science.gov (United States)

    Ran, Chao; Huang, Lu; Hu, Jun; Tacon, Philippe; He, Suxu; Li, Zhimin; Wang, Yibing; Liu, Zhi; Xu, Li; Yang, Yalin; Zhou, Zhigang

    2016-09-01

    In this study, the effects of baker's yeast as probiotics was evaluated in Nile tilapia reared at high density. Juvenile tilapia were distributed to tanks at high density (436 fish/m(3)) and fed with basal diet (CK) or diets supplemented with live (LY) or heat-inactivated yeast (HIY). Another group of fish reared at low density (218 fish/m(3)) and fed with basal diet was also included (LowCK). After 8 weeks of feeding, growth, feed utilization, gut microvilli morphology, digestive enzymes, and expressions of hsp70 and inflammation-related cytokines in the intestine were assessed. Intestinal microbiota was investigated using 16S rRNA gene pyrosequencing. Fish were challenged with Aeromonas hydrophila to evaluate disease resistance. High rearing density significantly decreased the growth, feed utilization, microvilli length, and disease resistance of fish (CK versus LowCK). Moreover, the intestinal hsp70 expression was increased in fish reared at high density, supporting a stress condition. Compared to CK group, supplementation of live yeast significantly increased gut microvilli length and trypsin activity, decreased intestinal hsp70 expression, and enhanced resistance of fish against A. hydrophila (reflected by reduced intestinal alkaline phosphatase activity 24 h post infection). The gut microbiota was not markedly influenced by either rearing density or yeast supplementation. Heat-inactivated yeast (HIY) didn't display the beneficial effects observed in LY except an increase in gut trypsin activity, suggesting the importance of yeast viability and thus secretory metabolites of yeast. In conclusion, live baker's yeast may alleviate the negative effects induced by crowding stress, and has the potential to be used as probiotics for tilapia reared at high density.

  15. Isolation and characterization of Streptococcus spp. group B in Nile tilapias (Oreochromis niloticus reared in hapas nets and earth nurseries in the northern region of Parana State, Brazil

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    Salvador Rogério

    2005-01-01

    Full Text Available The objective of this study was to isolate and characterize Streptococcus spp. in Nile tilapias (Oreochromis niloticus reared in net-pens and earth nurseries. Eight intensive tilapia-rearing farms were investigated in north Paraná, Brazil from April 1st 2001 to April 30th 2002. The fish were reared in a system of hapas nets on four farms and in earth nurseries on other four farms. A total of 370 samples were analyzed of material collected from 120 fish (brain, liver, kidney, skin scrapes, ascites liquid and eye that were sown on BHI agar (Brain Heart Infusion supplemented with 1% yeast extract and sheep blood. Streptococcus spp. was isolated in 36 of the samples (18 brain, eight liver, eight kidney and two ascites liquid from 25 fish. Streptococci were isolated in both systems, almost in the same proportion. First the streptococci were characterized by the catalase and esculin test, growth in methylene blue and sodium chloride at 6.5%. They were classified in groups by the Slidex Strepto-Kit (BioMerieux, France. The phenotypic characteristics were determined by the Api 20 Strep microtest system (BioMerieux, France. The 36 Streptococcus spp. samples did not present hemolysis and were classified as Lancefield group B. Further 16 samples were identified as Streptococcus agalactiae and 20 were not identified by the Api 20 Strep, but presented the same biochemical profile described for the reference strain of Streptococcus difficile (ND-2-22.

  16. [The influence of branchial parasitism by monogenoid trematodes on the development of Nile tilapia (Oreochromis niloticus) Linnaeus, 1757 bred in net-pond systems in Capivara Dam, PR].

    Science.gov (United States)

    Zanolo, Rodrigo; Leonhardt, Júlio Hermann; Silva e Souza, Angela Teresa; Yamamura, Milton Hissashi

    2009-01-01

    Tilapias are fish originally from Africa which nowadays are commercially bred in almost 100 countries, being one of the most commercially bred species in the world. In this work the trematode population of the monogenoidea group present in the branchiae of Nile tilapias bred in 4 net-ponds with volume of 4 m3 each, was monitored during 5 months. The juvenile fish, presenting initial average weight of 37.65 g originated from other piscicultures, were stocked in the density of 250 animals.m(-3) and monthly monitored until their commercialization, with final average weight of 485.4 g. The prevalence of these ectoparisites was high, between 90 and 100% in all months. The highest values of average intensity of infestation--AII and average abundance of infection--AAI occurred during the 2 first months of captivity, presenting a new increase in the last month of breeding. The only monogenoidea group present in the branchiae of the animals examined belonged to the Dactylogyridae family. The values of the dissolved oxygen, temperature, pH, nitrite and ammonia were within normal rate. In these conditions there were no significant differences between the relative condition factor--Kn among the parasited and non-parasited animals and also in the different levels of infestation, showing that, in these breeding conditions, the relationship parasite-host-environment presented itself in balance without causing great harm to the animals.

  17. Effects of Cordyceps militaris spent mushroom substrate on mucosal and serum immune parameters, disease resistance and growth performance of Nile tilapia, (Oreochromis niloticus).

    Science.gov (United States)

    Doan, Hien Van; Hoseinifar, Seyed Hossein; Tapingkae, Wanaporn; Chitmanat, Chanagun; Mekchay, Supamit

    2017-08-01

    The aim of present study was determination effects of dietary administration of C. militaris spent mushroom substrate (SMS) on mucosal and serum immune parameters, disease resistance, and growth performance of Nile tilapia (Oreochromis niloticus). Two hundred twenty five fish of similar weight (37.28 ± 0.10 g) were assigned to the following diets [0 (T1- Control), 5 (T2), 10 (T3), 20 (T4) and 40 g kg(-1) (T5) SMS]. After 60 days of feeding trial, growth performance, skin mucus lysozyme and peroxidase activities as well as serum innate immune were measured. In addition, survival rate and innate immune responses were calculated after challenge test (15 days) against Streptococcus agalactiae. The results revealed that regardless of inclusion levels, feeding Nile tilapia with SMS supplemented diets significantly increased skin mucus lysozyme and peroxidase activities as well as serum immune parameters (SL, ACH50, PI, RB, and RB) compared control group (P < 0.05). The highest increment of immune parameters was observed in fish fed 10 g kg(-1) SMS which was significantly higher than other treatments (P < 0.05). Also, the relative percent survival (RSP) in T2, T3, T4, and T5 was 61.11%, 88.89%, 66.67, and 55.56%, respectively. Among the supplemented groups, fish fed 10 g kg(-1) SMS showed significant higher RPS and resistance to S. agalactiae than other groups (P < 0.05). Regarding the growth performance, SGR, WG, FW, and FCR were remarkably improved (P < 0.05) in SMS groups; the highest improvement observed in 10 g kg(-1) SMS treatment. According to these finding, administration of 10 g kg(-1) SMS is suggested in tilapia to improve growth performance and health status. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Effects of Garlic (Alliumsativum and chloramphenicol on growth performance, physiological parameters and survival of Nile tilapia (Oreochromis niloticus

    Directory of Open Access Journals (Sweden)

    A. M. Shalaby

    2006-04-01

    Full Text Available We studied and compared the effects of chloramphenicol antibiotic and garlic (Allium sativum, used as immunostimulants and growth promoters, on some physiological parameters, growth performance, survival rate, and bacteriological characteristics of Nile tilapia (Oreochromis niloticus. Fish (7±1g/fish were assigned to eight treatments, with three replicates each. Treatment groups had a different level of Allium sativum (10, 20, 30, and 40g/kg diet and chloramphenicol (15, 30, and 45mg/kg diet added to their diets; the control group diet was free from garlic and antibiotic. Diets also contained 32% crude protein (CP and were administered at a rate of 3% live body weight twice daily for 90 days. Results showed that the final weight and specific growth rate (SGR of O. niloticus increased significantly with increasing levels of Allium sativum and chloramphenicol. The highest growth performance was verified with 30g Allium sativum / kg diet and 30mg chloramphenicol / kg diet. The lowest feed conversion ratio (FCR was observed with 30g Allium sativum / kg diet and 30mg chloramphenicol / kg diet. There were significant differences in the protein efficiency ratio (PER with all treatments, except with 45mg chloramphenicol / kg diet. No changes in the hepatosomatic index and survival rate were observed. Crude protein content in whole fish increased significantly in the group fed on 30g Allium sativum / kg diet, while total lipids decreased significantly in the same group. Ash of whole fish showed significantly high values with 30g Allium sativum and 15mg chloramphenicol / kg diet while the lowest value was observed in the control group. Blood parameters, erythrocyte count (RBC, and hemoglobin content in fish fed on diets containing 40g Allium sativum and all levels of chloramphenicol were significantly higher than in control. Significantly higher hematocrit values were seen with 30 and 45mg chloramphenicol / kg diet. There were no significant differences

  19. Vitamin A in diets for Nile tilapia Vitamina A em dietas para tilápia do Nilo

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    Daniela Ferraz Bacconi Campeche

    2009-12-01

    Full Text Available Dietary vitamin supplementation decrease stress caused by high stocking density, and boosts immunological system of farmed fish. A studied was carried out to determine vitamin A requirements of Nile tilapia (Oreochromis niloticus in an all male group (13.8 ± 1.2 g and a mixed sex population (9.8 ± 2.3 g. Fish stocked in 100-L plastic aquaria (26.0 ± 1.0ºC were fed to near satiety, twice a day, seven days a week, during 75 days with vitamin A-free, semi-purified diets supplemented with 0; 600; 1,200; 1,800; 2,400; 3,000; 3,600; 4,200; 4,800 and 5,400 International Units (IU of retinyl palmitate (30% vitamin A per kg of diet in a completely randomized experimental design, factorial arrangement 2c10 (n = 4. Deficiency signs of vitamin A were observed in fish fed 0 to 1.200 IU vitamin A kg-1 diet; moderate signs were observed in fish fed diets with 1.800 to 3.600 IU vitamin A kg-1 diet; no interactions group*level (p 0.05. A group effect was observed regarding all performance variables (p A suplementação de vitaminas na dieta diminui o estresse e estimula o sistema imunológico causado por altas densidades de estocagem dos peixes. Este trabalho determinou a exigência em vitamina A para a tilápia do Nilo em uma população monosexo masculina (13.8 ± 1.2 g e em uma população original (9.8 ± 2.3 g. Os peixes foram estocados em aquários plásticos de 100 L (26.0 ± 1.0ºC e alimentados "ad libitum", duas vezes ao dia, sete dias da semana, durante 75 dias com dieta semi-purificada suplementada com 0; 600; 1.200; 1.800; 2.400; 3.000; 3.600; 4.200; 4.800 e 5.400 UI de retinyl palmitato (30% de vitamina A por kg de dieta, em um delineamento experimental totalmente ao acaso e arranjo fatorial 2c10 (n = 4. Deficiência nutricional severa foi observada em peixes alimentados com 0 a 1.200 UI vitamina A kg-1 de dieta; sinais moderados foram encontrados em peixes alimentados com 1.800 a 3.600 UI vitamina A kg-1 de dieta; interações grupo*nível (p

  20. Local ecological knowledge is not a useful source of information concerning impacts caused by non-native Nile tilapia on fishery stocks - doi 10.4025/actascibiolsci.v35i3.18418

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    José da Silva Mourão

    2013-08-01

    Full Text Available Exotic freshwater fish can have deleterious effects on local biodiversity, although these impacts often only become apparent many years after the introduction. Local Ecological Knowledge (LEK may be a useful source of information in situations where formal technical studies are insufficient, but few works have examined the reliability of information generated through this approach. We examined the reliability of LEK by investigating the impacts of Nile tilapia on fishery stocks in an artificial reservoir in northeastern Brazil. We gathered LEK from 29 experienced fishermen and then confronted this information with official fishery statistics from the same site. Twenty-two fishermen stated that total catch in the Gargalheiras Reservoir had declined over the years, 68% (N=15 of them began fishing before 1976 (the year Nile tilapia was introduced into reservoir. Of those 15 fishermen, 87% (N=13 stated that tilapia has not negatively affected other species, which ran counter to analyses of fishery statistics. Our study suggests that the LEK of fishermen is not a useful source of information concerning the impacts caused by exotic tilapia. However, the LEK added an overfishing hypothesis of the decline in fishery stocks in the Gargalheiras reservoir.   

  1. Effects of CaCO3 liming on water quality and growth performance of fingerlings of Nile tilapia, Oreochromis niloticus - DOI: 10.4025/actascianimsci.v31i3.6263

    Directory of Open Access Journals (Sweden)

    Frederico Batista Magalhães

    2009-09-01

    Full Text Available The present study was carried out for 6 week with Nile tilapia, Oreochomis niloticus, fingerlings (0.77 ± 0.04 g to assess the effects of moderate CaCO3 liming on water pH, total alkalinity, calcium hardness, free CO2 and total ammonia, as well as on fish final body weight, final body length, survival and FCR. Eighteen 25-L polyethylene aquaria were used to hold the experimental fish (15 fish per aquarium. Nine aquaria were set in the lab’s indoor room and nine aquaria in its outdoor area. Two types of water (clear or green and three different water quality managements (none, HCl acidification and CaCO3 liming were evaluated simultaneously in a 3 x 2 factorial design. The application of analytical calcium carbonate at 1 g 10 L-1 in the clear or green waters has produced superior Nile tilapia fingerlings’ final body weight and length. The best set of limnological conditions that improved Nile tilapia fingerlings growth was the following: pH: 7.4-8.2; total alkalinity > 50 mg L-1; calcium hardness > 140 mg L-1; free CO2 -1. The total ammonia concentration in fish aquaria was not affected by CaCO3 liming (p > 0.05.

  2. A Cultural Herpetology of Nile Crocodiles in Africa

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    Simon Pooley

    2016-01-01

    Full Text Available Human-wildlife conflict is a growing problem worldwide wherever humans share landscapes with large predators, and negative encounters with eight species of the crocodilians is particularly widespread. Conservationists' responses to these adverse encounters have focused on the ecological and behavioural aspects of predators, rather than on the social, political, and cultural contexts, which have threatened their existence in the first place. Few studies have thus far tried to understand the rich, varied, contradictory, and complex relations that exist between particular humans and human societies, and particular predators and groups of predators. It is in the spirit of Brian Morris's explorations of the interactional encounters and co-produced sociabilities that exist between humans and animals in specific places and regions that this paper offers a cultural herpetology (an account of human-crocodile interrelations of the Nile crocodile (Crocodilus niloticus and C. suchus in Africa. It draws on extensive historical documentation of the interactions of humans and crocodiles across Africa to examine how diverse and complex human responses to Nile crocodiles have been, and continue to be, and suggests some implications for improving human-crocodile relations.

  3. Flora bacteriana de tilápia do Nilo, Oreochromis niloticus, cultivada em sistema semi-intensivo - DOI: 10.4025/actascibiolsci.v25i2.2007 Bacterial microflora in the gastrointestinal tract of Nile tilapia, Oreochromis niloticus, cultured in a semi-intensive system- DOI: 10.4025/actascibiolsci.v25i2.2007

    Directory of Open Access Journals (Sweden)

    Benetido Prado Dias Filho

    2003-04-01

    Full Text Available A flora bacteriana de diferentes partes do trato gastrintestinal de tilápia Oreochomis niloticus L. (Cichlidae foi determinada. O número médio de bactérias foi maior no intestino anterior e posterior quando comparado ao estômago. A porcentagem total de espécies bacterianas isoladas e a porcentagem de espécies isoladas em uma espécie particular variaram significativamente entre as regiões do trato gastrintestinal. Aeromonas hydrophila, Aeromonas veronii, Burkholderia cepacia, Chromobacterium violaceum, Citrobacter freundii, Escherichia coli, Flavimonas oryzihabitans e Plesiomonas shigelloides foram os bacilos Gram-negativos encontrados com maior freqüência. Destas espécies, somente Plesiomonas shigelloides esteve presente em cada região do trato gastrintestinal, apresentando maior número no intestino posterior (76%, quando comparado com o intestino anterior (4.8% e o estômago (0.6%. Aeromonas hydrophila (0.6%, Escherichia coli (7.4%, e Flavimonas oryzihabitans foram isoladas somente do estômago, e Citrobacter freundii e Burkholderia cepacia foram encontradas somente no intestino posterior. Chromobacterium violaceum foi a espécie dominante isolada do estômago e do intestino anterior com 90% e 55%, respectivamente. Organismos não identificados compreendem 0 – 39.3% da microbiota gastrintestinalThis experiment measured total bacterial numbers in the gastrointestinal regions of semi-intensively cultured tilapia, Oreochromis niloticus L. (Cichlidae. Mean bacterial numbers were higher in both anterior and posterior gut than in stomach. The percentage of isolated species and the percentage of isolates from any particular species varied significantly among gastrointestinal tract regions. Aeromonas hydrophila, Aeromonas veronii, Burkholderia cepacia, Chromobacterium violaceum, Citrobacter freundii, Escherichia coli, Flavimonas oryzihabitans and Plesiomonas shigelloides were the most frequently isolated Gram-negative bacilli. From

  4. Exigências de lisina digestível para juvenis de tilápia-do-nilo Digestible lysine requirements of Nile tilapia juveniles

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    Wilson Massamitu Furuya

    2006-06-01

    Full Text Available Este estudo foi realizado com o objetivo de determinar a exigência de lisina digestível para juvenis de tilápia-do-nilo. Noventa e seis peixes revertidos sexualmente e com peso vivo inicial de 5,72 ± 0,10 g foram alimentados por 42 dias com quatro rações (29.51% de PB e 3.235 kcal de energia digestível/kg contendo diferentes níveis de L-lisina HCl (0,1; 0,3; 0,5 e 0,7%, correspondendo a rações com 1,04; 1,27; 1,51 e 1,741% de lisina digestível, respectivamente. Os peixes foram distribuídos em 16 tanques com capacidade de 1.000 L cada um, em um delineamento inteiramente casualizado, com quatro tratamentos, três repetições e seis peixes por unidade experimental. Não foi observado efeito dos níveis de lisina sobre o índice hepato-somático, a gordura visceral, a sobrevivência e os teores de água e extrato etéreo na carcaça. A análise de Linear Response Plateau do ganho de peso e da conversão alimentar versus níveis de lisina digestível demonstrou estimativa de exigência de 1,56 e 1,44% de lisina digestível, respectivamente. Foi observado efeito quadrático sobre o rendimento de carcaça, que aumentou até o nível de 1,61% de lisina digestível. Considerando o desempenho, recomenda-se que dietas para juvenis de tilápia-do-nilo devem conter 1,44% de lisina digestível (5,23% da proteína da dieta.This trial was carried out to determine the digestible lysine requirements of Nile tilapia juveniles. Ninety- six reverted fishes averaging initial weight of 5.72 ± 0.10 g were fed four diets (29.51% of crude protein and 3,235 kcal/kg of digestible energy containing increasing levels of L-lysine HCl (0.1, 0.3, 0.5, and 0.7%, during 42 days. The following treatments were evaluated: dietary lysine levels of 1.04; 1.27; 1.51 and 1.741%. Fishes were allotted to 1000-L 16 tanks, as a completely randomized design with four treatments, three replicates and eight fishes per experimental unit. No treatment effects on hepatosomatic index

  5. Effects of tilapia (Oreochromis niloticus L.) stocking and artificial feeding on water quality and production in rohu-common carp bi-culture ponds

    NARCIS (Netherlands)

    Rahman, M.M.; Verdegem, M.C.J.; Wahab, M.A.

    2008-01-01

    Previous research showed that stocking 1.5 rohu (Labeo rohita) and 0.5 common carp (Cyprinus carpio) m¿2 yields the highest production in small holder ponds in Bangladesh. The present study looked into the effects of additional stocking of Nile tilapia (Oreochromis nilotica) in fed or non-fed ponds

  6. Evaluation of reference genes for quantitative real-time RT-PCR analysis of gene expression in Nile tilapia (Oreochromis niloticus).

    Science.gov (United States)

    Yang, Chang Geng; Wang, Xian Li; Tian, Juan; Liu, Wei; Wu, Fan; Jiang, Ming; Wen, Hua

    2013-09-15

    Quantitative real-time reverse-transcriptase polymerase chain reaction (RT-qPCR) has been used frequently to study gene expression related to fish immunology. In such studies, a stable reference gene should be selected to correct the expression of the target gene. In this study, seven candidate reference genes (glyceraldehyde-3-phosphate dehydrogenase (GADPH), ubiquitin-conjugating enzyme (UBCE), 18S ribosomal RNA (18S rRNA), beta-2-microglobulin (B2M), elongation factor 1 alpha (EF1A), tubulin alpha chain-like (TUBA) and beta actin (ACTB)), were selected to analyze their stability and normalization in seven tissues (liver, spleen, kidney, brain, heart, muscle and intestine) of Nile tilapia (Oreochromis niloticus) challenged with Streptococcus agalactiae or Streptococcus iniae, respectively. The results showed that all the candidate reference genes exhibited tissue-dependent transcriptional variations. With PBS injection as a control, UBCE was the most stable and suitable single reference gene in the intestine, liver, brain, kidney, and spleen after S. iniae infection, and in the liver, kidney, and spleen after S. agalactiae infection. EF1A was the most suitable in heart and muscle after S. iniae or S. agalactiae infection. GADPH was the most suitable gene in intestine and brain after S. agalactiae infection. In normal conditions, UBCE and 18S rRNA were the most stably expressed genes across the various tissues. These results showed that for RT-qPCR analysis of tilapia, selecting two or more reference genes may be more suitable for cross-tissue analysis of gene expression.

  7. Evaluation and Selection of Appropriate Reference Genes for Real-Time Quantitative PCR Analysis of Gene Expression in Nile Tilapia (Oreochromis niloticus) during Vaccination and Infection.

    Science.gov (United States)

    Wang, Erlong; Wang, Kaiyu; Chen, Defang; Wang, Jun; He, Yang; Long, Bo; Yang, Lei; Yang, Qian; Geng, Yi; Huang, Xiaoli; Ouyang, Ping; Lai, Weimin

    2015-04-30

    qPCR as a powerful and attractive methodology has been widely applied to aquaculture researches for gene expression analyses. However, the suitable reference selection is critical for normalizing target genes expression in qPCR. In the present study, six commonly used endogenous controls were selected as candidate reference genes to evaluate and analyze their expression levels, stabilities and normalization to immune-related gene IgM expression during vaccination and infection in spleen of tilapia with RefFinder and GeNorm programs. The results showed that all of these candidate reference genes exhibited transcriptional variations to some extent at different periods. Among them, EF1A was the most stable reference with RefFinder, followed by 18S rRNA, ACTB, UBCE, TUBA and GAPDH respectively and the optimal number of reference genes for IgM normalization under different experiment sets was two with GeNorm. Meanwhile, combination the Cq (quantification cycle) value and the recommended comprehensive ranking of reference genes, EF1A and ACTB, the two optimal reference genes, were used together as reference genes for accurate analysis of immune-related gene expression during vaccination and infection in Nile tilapia with qPCR. Moreover, the highest IgM expression level was at two weeks post-vaccination when normalized to EF1A, 18S rRNA, ACTB, and EF1A together with ACTB compared to one week post-vaccination before normalizing, which was also consistent with the IgM antibody titers detection by ELISA.

  8. Effect of acute exposure to nonylphenol on biochemical, hormonal, and hematological parameters and muscle tissues residues of Nile tilapia; Oreochromis niloticus

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    Hager Tarek H. Ismail

    2016-06-01

    Full Text Available Aim: This study is aimed to evaluate some biochemical, hormonal, hematological, and histopathological changes in Nile tilapia, Oreochromis niloticus, after acute exposure to nonylphenol (NP. In addition to detection of NP residues in the fish, muscle tissues for human health concern. Materials and Methods: A total of 90 apparently healthy Nile tilapia, O. niloticus, were randomly divided into three equal groups; each containing 30 fish (three replicates. Groups 1 and 2 kept as a control and solvent control (acetone, respectively, and Group 3 exposed to NP at a dose level of 500 μg/L water for 7 successive days. Blood and tissue samples were collected 2 times randomly from each group after 7 days from fish exposure to NP and 10 days from exposure stopping. Results: Fish exposed to NP Group 3 showed anorexia, sluggish movement, erythema of the skin, areas of scales loss, and hemorrhagic ulcers in some areas of body region leading to exposing the viscera. Biochemical results revealed a significant increase in serum total proteins and globulins levels, a highly significant increase in serum alanine aminotransferase and aspartate aminotransferase activities, triglycerides, cholesterol, and creatinine levels, insignificant increase in serum uric acid level, and a highly significant decrease in serum testosterone and estradiol-β17 levels in Group 3 in compare with the control group. Histopathological finding confirms these results. While hematological results of the same group revealed a significant increase in red blood cells count and packed cell volume value, insignificant increase in hemoglobin concentration, leukopenia, lymphopenia, and monocytopenia in compared with the control group. All of these changes appeared after 7 days from fish exposure to NP. Most of these alterations returned toward the normal level after 10 days from stopping exposure to NP. NP residues detected in fish muscle tissues of Group 3 during exposure and after stopping

  9. Valor nutritivo do farelo de coco para a tilápia-do-nilo (Oreochromis niloticus Nutritional value of coconut meal in diets for Nile tilapia (Oreochromis niloticus

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    Antonio Celso Pezzato

    2000-05-01

    Full Text Available Esse estudo teve por objetivo avaliar o potencial de utilização do farelo de coco em rações para a tilápia-do-nilo através do ganho de peso e de sua digestibilidade aparente. Esse subproduto foi avaliado em um experimento inteiramente casualizado, com quatro tratamentos e quatro repetições. As rações foram formuladas de forma a apresentarem-se isoprotéicas (28% PB e isoenergéticas (3060 kcal/ED/kg de ração, com a inclusão de 0, 10, 20 e 30% de farelo de coco. Foram utilizados sessenta e quatro alevinos com peso inicial de 0,75 gramas, os quais foram distribuídos em 16 aquários com capacidade de 80 litros cada, confeccionados em fibra de vidro, com sistema de renovação de água (0,2 litros/min, aeração e aquecimento (26,0ºC. A análise estatística revelou diferença estatística (p Employment of coconut meal in rations for Nile tilapia through weight gain and apparent digestibility was evaluated. Experimental design was completely randomized and consisted of four treatments and four replications. Four isonitrogenous (28%CP and isoenergetic (3060 kcal/ED/kg experimental rations were prepared with 0, 10, 20 and 30% of coconut meal. Sixty-four fingerlings, average initial weight of 0.75g, were distributed in 16 fiberglass-built aquariums, with a capacity of 80 L each, provided with water renovation (0.2 L/min, aeration and heater (26.0ºC. Whereas statistical analysis revealed significant difference among treatments (p < 0.01, coconut meal may be included in rations for Nile tilapia fingerlings up to 30.0%. The apparent digestibility coefficient for coconut meal was 60.53% for dry matter, 86.78% for crude protein, 94.64% for fat extract and 82.47% for mineral matter. Digestible energy amounted to 3525 kcal ED/kg and 19.97% for available phosphorus.

  10. A Tandem Duplicate of Anti-Mullerian Hormone with a Missense SNP on the Y Chromosome Is Essential for Male Sex Determination in Nile Tilapia, Oreochromis niloticus.

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    Minghui Li

    2015-11-01

    Full Text Available Variation in the TGF-β signaling pathway is emerging as an important mechanism by which gonadal sex determination is controlled in teleosts. Here we show that amhy, a Y-specific duplicate of the anti-Müllerian hormone (amh gene, induces male sex determination in Nile tilapia. amhy is a tandem duplicate located immediately downstream of amhΔ-y on the Y chromosome. The coding sequence of amhy was identical to the X-linked amh (amh except a missense SNP (C/T which changes an amino acid (Ser/Leu92 in the N-terminal region. amhy lacks 5608 bp of promoter sequence that is found in the X-linked amh homolog. The amhΔ-y contains several insertions and deletions in the promoter region, and even a 5 bp insertion in exonVI that results in a premature stop codon and thus a truncated protein product lacking the TGF-β binding domain. Both amhy and amhΔ-y expression is restricted to XY gonads from 5 days after hatching (dah onwards. CRISPR/Cas9 knockout of amhy in XY fish resulted in male to female sex reversal, while mutation of amhΔ-y alone could not. In contrast, overexpression of Amhy in XX fish, using a fosmid transgene that carries the amhy/amhΔ-y haplotype or a vector containing amhy ORF under the control of CMV promoter, resulted in female to male sex reversal, while overexpression of AmhΔ-y alone in XX fish could not. Knockout of the anti-Müllerian hormone receptor type II (amhrII in XY fish also resulted in 100% complete male to female sex reversal. Taken together, these results strongly suggest that the duplicated amhy with a missense SNP is the candidate sex determining gene and amhy/amhrII signal is essential for male sex determination in Nile tilapia. These findings highlight the conserved roles of TGF-β signaling pathway in fish sex determination.

  11. Mananoligossacarídeo em dietas para juvenis de tilápias do Nilo = Mannanoligosaccharides in diets for Nile tilapia, juveniles

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    Kátia Kalko Schwarz

    2010-04-01

    Full Text Available O presente estudo foi realizado com o objetivo de avaliar a inclusão de mananoligossacarídeo (MOS em dietas para juvenis de tilápias do Nilo. Foram utilizados 224 peixes (25 g ±1,0 g, em um período de 53 dias e os peixes foram distribuídos em um delineamento em blocos ao acaso, sendo considerado como bloco cada tanque de 1.000 L com 16 gaiolas de 0,12 m3 cada. Foi utilizada dieta-controle com 28,5% de proteína bruta e 2.855 kcal de energia digestível kg-1 e adicionado MOS nas proporções de 0, 1, 2 e 3%. Não foi observado efeito (p > 0,05 dos níveis de inclusão de MOS sobre o consumo, índicehepatossomático, sobrevivência, umidade, cinzas corporal, coeficiente de digestibilidade aparente da máteria seca, energia bruta, proteína bruta, extrato etéreo e disponibilidade das cinzas, densidade de vilos intestinais e número de células caliciformes por vilo. Os melhores resultados (p This study was carried out to assess the inclusion of mannanoligosaccharides (MOS in diets for Nile tilapia juveniles. Two-hundred and twenty fish with an average initial weight of approximately 25 ± 1.0 g were used, during 53 days. Fish were distributed in a randomized block design. Each 1,000 L tank with four cages (0.12 m3 each, was considered as a block; fish in each cage received a different dietary treatment. A control diet with 28.5% of crude protein and 2,855 kcal of digestible energy kg-1 was used anddietary MOS was included at 0, 1, 2 and 3%. No effects of MOS on feed intake, hepatosomatic index, survival, moisture, body ash, apparent digestibility coefficients of dry matter, gross energy, crude protein, ether extract and ash availability, intestinal villi density and number of goblet cells per villus were observed. The best values of feedto- gain ratio, protein efficiency ratio, body composition and villi height were observed in fish fed with dietary MOS. It was concluded that 1% of dietary MOS is adequate for Nile tilapia juveniles.

  12. Desempenho e atividade de amilase em tilápias-do-nilo submetidas a diferentes temperaturas Performance and amylase activity in Nile tilapia submitted to different temperatures

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    Guilherme de Souza Moura

    2007-11-01

    Full Text Available O objetivo deste trabalho foi avaliar o desempenho e a atividade de amilase em quimo de tilápias-do-nilo macho, linhagem tailandesa, submetidas a quatro diferentes temperaturas. O experimento foi conduzido em delineamento inteiramente casualizado, com quatro tratamentos (20, 24, 28 e 32ºC, seis repetições e dez peixes por unidade experimental. A dieta utilizada foi igual para todos os tratamentos. Aos 55 dias do experimento, o consumo de ração aparente, ganho de peso, conversão alimentar aparente, atividade de amilase e atividade específica da amilase foram avaliados. O consumo de ração aparente e o ganho de peso aumentaram linearmente com o aumento da temperatura. Na conversão alimentar aparente, foi observado efeito quadrático em função da temperatura com melhora na conversão de 1,79 a 1,00 com o aumento da temperatura até 29,15ºC. Observou-se efeito linear na atividade da amilase e na atividade específica da amilase em função da temperatura, com maior atividade de amilase e menor atividade específica de amilase a 32ºC. A temperatura da água influencia o desempenho e a atividade da amilase em tilápias-do-nilo.The objective of this work was to evaluate the performance and amylase activity in chime of Nile tilapia male, Thai line, submitted to four different temperatures. The experimental design was completely randomized with four treatments (20, 24, 28 and 32ºC, six replicates and ten fishes per experimental unit. The diet was the same for all treatments. At 55 days of experiment, apparent feed intake, weight gain, apparent feed conversion, amylase activity and specific amylase activity were evaluated. The apparent feed intake and weight gain increased linearly with temperature increase. For apparent feed conversion, quadratic effect was observed as a function of temperature, showing a conversion improvement of 1.79 to 1.00 with the increase of the temperature until 29,15ºC. Linear effect in amylase activity and

  13. Application of fungal chitosan incorporated with pomegranate peel extract as edible coating for microbiological, chemical and sensorial quality enhancement of Nile tilapia fillets.

    Science.gov (United States)

    Alsaggaf, Mohammed S; Moussa, Shaaban H; Tayel, Ahmed A

    2017-06-01

    Fish are generous sources for providing man with his essential nutritional requirements, but the extreme susceptibility to quality deterioration hinders their optimal usage and storage. Natural derivatives are always the perfect alternatives for food preservation. The application of fungal chitosan (Ch), from Aspergillus niger, and pomegranate peel extract (PPE), in coating films for Nile tilapia (Oreochromis niloticus) fillets preservation ‎and maintaining their microbiological, chemical and sensorial quality during cooled storage at 4°C for 30days, was investigated.‎ Fish fillet were coated with Ch (2%) and combined Ch+PPE, at PPE percentages of 0.5, 1.0, 1.5 and 2.0%. Fillets coating resulted in sharp decrease of the entire microbial counts during storage; the increased concentrations from PPE strengthened coating film antimicrobial activity. Additionally, fillets coating could retard the chemical spoilage parameters increasing, i.e. nitrogen volatile base (TVB-N), peroxide value (PV) and reactive substances of thiobarbituric acid (TBARS), during storage period. The sensory evaluation indicated higher preferences for the odor, texture, color and overall quality of coated samples. Fish fillets coating with Ch and Ch+PPE could be recommended for shelf life extension and maintaining the microbiological, chemical and sensorial quality through the application of safe preservatives from natural origins.

  14. Small crumbled diet versus powdered diet in restricted feeding management of juvenile Nile tilapia - doi: 10.4025/actascianimsci.v35i2.16767

    Directory of Open Access Journals (Sweden)

    José Nacélio Oliveira-Segundo

    2013-03-01

    Full Text Available Normal 0 21 false false false MicrosoftInternetExplorer4 The pellet size of the diet can affect both fish growth performance and the water quality of the rearing units. The present work assessed the effects of feeding juvenile Nile tilapia, Oreochromis niloticus (L. a small crumbled diet (SCD; 0.8 mm on water quality and growth performance. Fish were reared for six weeks in twenty 250-L polyethylene outdoor tanks at a density of 10 juveniles tank-1 (40 fish m-3. There were two feeding rates (standard and restricted and two types of artificial fish diet (powdered and SCD. The standard feeding rates were reduced by 30% for restricted feeding. The concentrations of free CO2, reactive phosphorus, total ammonia nitrogen (TAN and nitrite were higher in the full-fed tanks relative to the restricted-fed tanks. In the standard feeding rate groups, those tanks fed SCD had lower TAN and nitrite concentrations than tanks fed a powdered diet. The final body weight and specific growth rate of fish fed a restricted SCD were higher than the full-fed tanks. The higher levels of food waste in the powdered-diet tanks lead to impairment of fish growth performance.  

  15. Seasonal changes in length-weight relationship and condition factor of Nile tilapia, Oreochromis niloticus (Linnaeus, 1758 (Cichlidae in Lake Naivasha, Kenya

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    James Last Keyombe

    2017-01-01

    Full Text Available The study compared the length-weight relationship and condition factor (K of Nile tilapia (Oreochromis niloticus in Lake Naivasha, Kenya, between the wet and dry seasons. Fish samples were collected monthly by gill netting from February to December 2015. A total of 372 samples of O. niloticus were analysed. The b values in the length-weight relationships were observed as 3.077 and 3.366 in the wet and dry seasons, respectively. The values of b exhibited positive allometric growth which were the important indication that the species was growing faster in weight than length. The K values of the fish ranged 1.18-4.1 during the wet season and 0.8-3.0 during the dry season.  All mean monthly K values were found to be greater than 1, the highest being in June (2.33±0.05 and lowest in February (1.31±0.28, an indication of a healthy status and general well-being of the O. niloticus population in Lake Naivasha. The study concluded that seasonal variation has no great influence in the length-weight relationship and condition factor of O. niloticus in Lake Naivasha.

  16. Growth performance and intestinal histomorphology of Nile tilapia juveniles fed probiotics - doi: 10.4025/actascianimsci.v35i4.18610

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    Ivan Bernardoni Nakandakare

    2013-10-01

    Full Text Available The objective of this study was to assess the growth performance and the histomorphometric characterization of the middle intestine of GIFT strain Nile tilapia, Oreochromis niloticus juveniles fed probiotics, added either before or after the feed processing. The experimental design was completely randomized, with five treatments and five replications: pelleted feed without any probiotic; pelleted feed with inclusion of probiotic before the processing; pelleted feed with inclusion of probiotic after the processing; extruded feed without any probiotic and extruded feed with inclusion of probiotic after the processing. Two hundred and fifty juveniles were distributed in 25 aquaria (20L and fed for 63 days. Differences in the mean values of total weight were found at the end of the experiment. After 42 days of feed intake, significant differences in feed conversion were verified for treatments with extruded diets when compared to the pelleted ones. The fishes fed diets supplemented with probiotic presented increase in the thickness of the epithelium of the intestine. The best zootechnical performance was observed in the extruded diet supplemented with probiotic added after the feed processing. The inclusion of 4.0 x 108 CFU g-1 of Bacillus subtilis and 4.0 x 108 CFU g-1 of Bacillus toyoi in both the pelleted and the extruded diets promoted an increase in the thickness of the epithelial layer of the middle intestine.   

  17. Histopathological alterations in the liver and intestine of Nile tilapia Oreochromis niloticus exposed to long-term sublethal concentrations of cadmium chloride

    Science.gov (United States)

    Younis, Elsayed; Abdel-Warith, Abdel-Wahab; Al-Asgah, Nasser; Ebaid, Hossam

    2015-07-01

    Fingerlings of Nile tilapia Oreochromis niloticus were exposed to 1.68, 3.36, and 5.04 mg/L cadmium (as CdCl2), which represent 10%, 20%, and 30% of their previously determined 96-h LC50. After exposure for 20 days, sections of the liver and intestine of treated fish were examined histologically. Histopathological changes varied from slight to severe structural modification, depending on the exposure concentration. The hepatic tissues of fish exposed to 10% LC50 showed markedly increased vacuolation of the hepatocytes and coarse granulation of their cytoplasm. Abundant erythrocytic infiltration among the hepatocytes was observed in fish exposed to 20% LC50. In the intestinal tissues of fish exposed to all doses, goblet cells proliferated and were greatly increased in size, the longitudinal muscularis mucosa was disturbed and, in the crypts of the sub-mucosal layer, apoptosis increased, indicated by large numbers of degenerated nuclei. Large numbers of inflammatory cells and dilated blood vessels were observed in the intestine of the group treated with 30% LC50.

  18. Effects of the pharmaceuticals diclofenac and metoprolol on gene expression levels of enzymes of biotransformation, excretion pathways and estrogenicity in primary hepatocytes of Nile tilapia (Oreochromis niloticus).

    Science.gov (United States)

    Gröner, Frederike; Ziková, Andrea; Kloas, Werner

    2015-01-01

    The expression levels of key enzymes of the xenobiotic metabolism and excretion pathways concerning biotransformation phases I (cytochrome P4501A), II (glutathione S-transferase) and III (multidrug resistance protein) and of the estrogenic biomarker vitellogenin (vtg) were investigated in primary hepatocytes isolated from male Nile tilapia (Oreochromis niloticus) after exposure to diclofenac and metoprolol, two pharmaceuticals prevalent in the aquatic environment worldwide. The lowest test concentration (4×10(-9) M) was chosen to reflect an environmentally relevant exposure situation. Furthermore concentration dependent effects were investigated. Therefore a series of concentrations higher than the environmentally relevant range were used (10- and 100-fold). Diclofenac significantly induced all chosen biomarkers already at the environmentally relevant concentration indicating that biotransformation and elimination occur via the pathways under investigation. Estrogenic potential of this substance was demonstrated by VTG up-regulation as well. Metoprolol was either less effective than diclofenac or metabolized using different pathways. Key enzymes of the xenobiotic metabolism were less (CYP1A, GST) or not (MDRP) induced and a mild increase in vtg mRNA was detected only for 4×10(-8) M. No concentration-dependency for metoprolol was found.

  19. Toxicity of sediments from Bahía de Chetumal, México, as assessed by hepatic EROD induction and histology in nile tilapia Oreochromis niloticus.

    Science.gov (United States)

    Zapata-Pérez, O; Simá-Alvarez, R; Noreña-Barroso, E; Güemes, J; Gold-Bouchot, G; Ortega, A; Albores-Medina, A

    2000-01-01

    The effect of environmental pollutants present in sediments obtained from Bahía de Chetumal, a bay on the border between Mexico and Belize, was studied in nile tilapia (Oreochromis niloticus) intraperitoneally injected with sediment extracts from six different sites of the Bay. Sediment samples used for the study contained a variety of organic chemicals such as organochlorine pesticides, polychlorinated biphenyls (PCBs) and polynuclear aromatic hydrocarbons (PAHs). Total cytochrome P-450 and EROD activity were measured in fish liver. Haematological and histological analyses were also carried out. Hepatic P-450 content in treated fish increased from 43 to 240%, and EROD activity from 85 to 160% compared to controls. Extracts from two sampling sites inhibited EROD activity. There were positive significant correlations between P-450 content and the levels of PCBs 44 and 128. EROD activity correlated to HCB, op'-DDE, pp'-DDE, pp'-DDD, mirex and PCB 18 concentrations. Blood examination showed cell degeneration and binucleated leukocytes with abnormal chromatin. Extract treatment also resulted in foci of hyperplasia on the basement of gill lamellae, hypertrophy and oedema in gills and liver necrosis. Control fish showed no abnormalities. The results demonstrate that sediments from Bahía of Chetumal have the potential to cause histopathological, haematological and biochemical alterations in fish. The administration of sediment extracts to fish may serve as a useful test to screen the toxicity of sediments from different areas.

  20. Effect of pyrene on hepatic cytochrome P450 1A (CYP1A) expression in Nile Tilapia (Oreochromis niloticus).

    Science.gov (United States)

    Zapata-Pérez, O; Gold-Bouchot, G; Ortega, A; López, T; Albores, A

    2002-05-01

    The effect of pyrene on the regulation of the gene expression of cytochrome P4501A ( CYP1A) was studied in tilapia (Oreochromis niloticus), a tropical fish of great ecological and economical importance. To evaluate CYP1A mRNA, tilapia CYP1A cDNA was cloned, sequenced, and compared with those CYP1A reported sequences in the GeneBank DNA database. The top seven matches corresponded to CYP1A from other teleosts. Hepatic CYP1A mRNA levels showed a significant increase at day 1 after pyrene injection (20 mg kg(-1) body weight [BW]), and this CYP1A mRNA levels did not return to basal levels for up to 5 days. The immunoblot analysis of CYP1A protein levels using polyclonal rabbit-anti-trout antibodies in the liver of pyrene-treated (20 mg kg(-1) BW) tilapias showed a 1.9-fold increase at day 3 after injection. Ethoxyresorufin- O-deethylase (EROD) activity increased 18-fold with respect to control fish at day 3 after injection. CYP1A protein and EROD activity remained increased for 5 days after a single pyrene IP administration. Similarly, the highest concentration of 1-hydroxypyrene (1-OH pyrene) in bile was observed in fish sacrificed at day 3 after injection. EROD activity and 1-OH pyrene concentration showed a statistically significant correlation (r = 0.85) according to the Spearman test, suggesting the participation of this cytochrome in the biotransformation of pyrene.

  1. Technical evaluation of tilapia (Oreochromis niloticus) monoculture and tilapia-prawn (Macrobrachium rosenbergii) polyculture in earthen ponds with or without substrates for periphyton development

    NARCIS (Netherlands)

    Uddin, S.; Farzana, A.; Fatema, M.K.; Azim, M.E.; Wahab, M.A.; Verdegem, M.C.J.

    2007-01-01

    The effects of periphyton grown on bamboo substrate, on growth and production of Nile tilapia, Oreochromis niloticus (Genetically Improved Farmed Tilapia strain) in monoculture and polyculture with the freshwater prawn (Macrobrachium rosenbergii) were studied and economically evaluated. The experime

  2. Molecular and cytogenetic analysis of the telomeric (TTAGGG)n repetitive sequences in the Nile tilapia, Oreochromis niloticus (Teleostei: Cichlidae).

    Science.gov (United States)

    Chew, Joyce S K; Oliveira, Claudio; Wright, Jonathan M; Dobson, Melanie J

    2002-03-01

    The majority of chromosomes in Oreochromis niloticus, as with most fish karyotyped to date, cannot be individually identified owing to their small size. As a first step in establishing a physical map for this important aquaculture species of tilapia we have analyzed the location of the vertebrate telomeric repeat sequence, (TTAGGG)n, in O. niloticus. Southern blot hybridization analysis and a Bal31 sensitivity assay confirm that the vertebrate telomeric repeat is indeed present at O. niloticus chromosomal ends with repeat tracts extending for 4-10 kb on chromosomal ends in erythrocytes. Fluorescent in situ hybridization revealed that (TTAGGG)n is found not only at telomeres, but also at two interstitial loci on chromosome 1. These data support the hypothesis that chromosome 1, which is significantly larger than all the other chromosomes in the karyotype, was produced by the fusion of three chromosomes and explain the overall reduction of chromosomal number from the ancestral teleost karyotype of 2n=48 to 2n=44 observed in tilapia.

  3. Construction of a microarrayed Fosmid library and its application in gene isolation in the Nile tilapia( Oreochromis niloticus)%尼罗罗非鱼微阵列Fosmid基因组文库的构建及基因筛选

    Institute of Scientific and Technical Information of China (English)

    李明辉; 魏莹莹; 焦静; 顾源; 王德寿; 吴风瑞; 熊传奇; 曾圣; 杨世杰; 叶凯; 蒋汶洮; 孙运侣; 黄宝锋

    2011-01-01

    以pCC2FOS为载体构建尼罗罗非鱼Fosmid基因组文库,共挑选115 200个单菌落,保存在300块384孔样品板中,构建4 800个行池、7 200个列池、300个板池和25个超级池,形成微阵列,并对其进行复制备份.该文库插入片段平均长度约为40 kb,覆盖约罗非鱼基因组的3倍.连续传代实验研究表明,文库具有良好的稳定性.由于构建超级池-板池-行、列池三级池系统形成的微阵列,有助于快速、准确、有效地筛选目的基因,仅需77个PCR反应(超级池25+板池12+行池16+列池24)就能筛选到含有目的基因的一个单克隆,解决了普遍存在的文库筛选难题.通过文库尝试筛选18个与性别分化和生长相关基因,均获得2~5个阳性克隆,说明文库具有较好的实用性.%Genomic DNA prepared from the Nile tilapia testis was used for Fosmid library construction.It was randomly sheared to -40 kb fragments.End-repair and recovery of the size-fractionated DNA were manipulated according to the manufacturer's protocols.Ligation of the end-repaired fragments into the Fosmid vector pCC2FOS(Epicentre,USA) was performed by using T4 DNA ligase for 16 h at 4 ℃.Fosmid clones were packaged using MaxPlaxi Lambda packaging extract provided by the kit.Infected EPI300TM-T1R cells were grown at 37 ℃ in solid medium overnight.Well-separated colonies were picked out and transferred into individual wells of 384-well plates ,each well with 300 L culture medium.After overnight incubation at 37 ℃,100 L medium was transferred from each of the 24 wells of every row of the 384-well plates into one well of the 96-well plate to construct row-pools.Totally 16 row-pools were constructed for each 384-well plate.Similarly,100 L medium was transferred from each of the 16 wells of every column of the 384 well plates into one well of the 96-well plate to construct column-pools.Totally 24 column-pools were constructed for each 384-well plate.Plate-pools were constructed by

  4. Digestibilidade Aparente de Ingredientes pela Tilápia do Nilo (Oreochromis niloticus Apparent Digestibility of Feedstuffs by Nile Tilapia (Oreochromis niloticus

    Directory of Open Access Journals (Sweden)

    Luiz Edivaldo Pezzato

    2002-07-01

    Full Text Available Avaliou-se a digestibilidade aparente do milho, amido de milho, milho extrusado, germe de milho, sorgo, farelo de trigo, farelo de arroz, glúten 21, glúten 60, farelo de soja, farelo de canola, farelo de algodão, farinha de peixe, farinha de carne, farinha de vísceras de aves, farinha de sangue e farinha de penas. Confeccionaram-se 18 rações, marcadas com 0,10% de óxido de crômio III, uma delas, basal purificada, e as demais, contendo os ingredientes. Os peixes, 100 juvenis com 100±10 g, foram alojados em cinco tanques-rede para facilitar o manejo de alimentação e a coleta de fezes e permaneceram, durante o dia, em cinco aquários (250 L de alimentação, recebendo refeições à vontade das 8 às 17h30. Após, foram transferidos para cinco aquários (300 L de coleta de fezes, onde permaneceram até a manhã do dia subseqüente. O coeficiente de digestibilidade aparente dos ingredientes foi calculado com base no teor de óxido crômio da ração e das fezes. Com base nos resultados, concluiu-se que, entre os ingredientes energéticos, o milho apresentou o melhor coeficiente de digestibilidade aparente, seguindo-se o milho extrusado, o farelo de trigo e o farelo de arroz; dos ingredientes protéicos - vegetal, o glúten 60 e o glúten 21, seguidos do farelo de canola, apresentou os melhores coeficientes e dos protéicos - animal, destacou-se a farinha de vísceras de aves, seguida da farinha de peixes, enquanto os piores coeficientes foram proporcionados pela farinha de penas e farinha de sangue.Apparent digestibility of corn, corn-starch, extruded corn, corn-germ, sorghum, wheat middlings, rice meal, corn gluten meal, gluten 60, soybean meal, canola meal, cottonseed meal, fish meal, meat and bone meal, poultry by-product meal, blood meal and poultry feathers hydrolyzed meal were determined for Nile tilapia juveniles (100±10 g fed purified diet and 0.10% chromic oxide. Fish were maintained in 5 aquaria (250 L at a density of 20 fish

  5. Níveis de teonina em rações para tilápias-do-nilo Threonine levels in diets for Nile tilapia

    Directory of Open Access Journals (Sweden)

    Lilian Carolina Rosa Silva

    2006-08-01

    Full Text Available Este estudo foi realizado para determinar a exigência de treonina para tilápia-do-nilo. Os peixes (37,61 ± 1,16 g de peso inicial foram distribuídos em um delineamento inteiramente casualizado, com quatro tratamentos, três repetições e 25 peixes por unidade experimental. Foi utilizada uma ração-referência (27% de PB e 3.000 kcal de ED/kg suplementada com L-treonina, resultando em rações com 0,92; 1,06; 1,21 e 1,35% de treonina total. Os aminoácidos sintéticos foram adicionados para manutenção do perfil de aminoácidos, de acordo com o conceito de proteína ideal. Os peixes foram alimentados até saciedade aparente durante 110 dias. Não foram observados efeitos dos níveis de treonina nas rações sobre o consumo de ração, o peso do fígado, o índice hepato-somático, os rendimentos de carcaça e de filé e a composição do filé em água (PB e EE. Constatou-se aumento linear sobre o ganho de peso, a conversão alimentar, a taxa de eficiência protéica, a retenção de nitrogênio, os pesos da carcaça e do filé e o teor de cinzas no filé. Considerando os resultados de desempenho, de custo/kg de ganho de peso e de custo/kg de peso em filés, pode-se inferir que tilápias-do-nilo de 38 a 351 g criadas em tanques-rede necessitam de 1,35% de treonina na ração - 5,51% da proteína digestível ou 74% de lisina (com base no conceito de proteína ideal.This experiment was conducted to determine the dietary threonine requirements for Nile tilapia. The fishes (37.61 ± 1.16 of initial weight were allotted to a completely randomized design with four treatments, three replicates and 25 fishes per experimental unit. It was used a reference diet with 27% of CP and 3,000 kcal of DE/kg, supplemented with L-threonine, resulting in diets with 0.92, 1.06, 1.21, and 1.35% of total threonine. Synthetic amino acids were added to mantain their profile according to the ideal protein concept. Fishes were fed ad libitum during 110 days. No

  6. Digestibilidade aparente da farinha de aguapé em tilápias-do-nilo Apparent digestibility of water hyacinth meal by Nile tilapia

    Directory of Open Access Journals (Sweden)

    José Francisco Vicente Biudes

    2009-11-01

    Full Text Available Objetivou-se com este trabalho determinar e comparar as digestibilidades aparentes da matéria seca (MS, proteína bruta (PB, extrato etéreo (EE e energia bruta (EB e as disponibilidades aparentes de minerais das farinhas da biomassa emersa (lâmina foliar e pecíolo, submersa (raiz e rizoma e total do aguapé em tilápias-do-nilo (Oreochromis niloticus. Foram elaboradas quatro rações marcadas com 0,10% de óxido de crômio-III (uma ração-referência purificada e três contendo 30,0% de cada ingrediente. As tilápias-do-nilo (125,5 ± 10,5 g foram alimentadas até a saciedade e a coleta de fezes foi realizada pelo sistema Ghelph modificado. As digestibilidades aparentes da farinha da biomassa emersa (MS = 57,8; PB = 72,3; EE = 63,2 e EB = 62,0% foram maiores que as das farinhas da biomassa total (MS = 45,7; PB = 57,3; EE = 50,3 e EB = 42,3% e submersa (MS = 38,3; PB = 50,8; EE = 43,5 e EB = 32,0%. As disponibilidades aparentes de fósforo (P, cálcio (Ca, magnésio (Mg, manganês (Mn, cobre (Cu e zinco (Zn da farinha da biomassa emersa também foram maiores. A farinha de biomassa emersa do aguapé apresenta melhor digestibilidade e disponibilidade aparente dos nutrientes em comparação às farinhas da biomassa total e submersa.This study was carried out to determine and compare the apparent digestibility of dry matter (DM, crude protein (CP, crude fat (CF, gross energy (GE, and the apparent availability of minerals (P, Ca, Mg, Mn, Cu, and Zn of emergent (leaf and petiole, submerged (root and rhizome and total biomass meal of water hyacinth for Nile tilapia. Four diets were prepared, containing 0.10% chromic oxide-III, one being the reference diet (purified and the others containing 30% of each ingredient. The Nile tilapias (125.5 ± 10.5 g were fed until satiation and the feces were collected by the modified Guelph system. The apparent digestibility of emergent biomass meal (DM = 57.8, CP = 72.3, CF = 63.2, and GE = 62.0% was higher than

  7. Saccharomyces cerevisiae como probiótico para alevinos de tilápia-do-nilo submetidos a desafio sanitário Saccharomyces cerevisiae as probiotic for Nile tilapia fingerlings submitted to a sanitary challenge

    Directory of Open Access Journals (Sweden)

    Fábio Meurer

    2007-10-01

    randomized design with two treatments and six replications in 12 aquariums of 50 L. As a sanitary challenged each aquarium daily received, during the experimental period, an equivalent of 0.5 mL fresh swine manure. The treatments consisted of a ration with (0.1% SC or without probiotic. At the end of the experiment the fingerlings were counted, measured and weighed. The intestines from two fingerlings randomly chosen were also removed and weighed per each treatment. Content of the intestines was submitted to a counting of the number of total bacteria and total coliformes presents. Performance and survival was not influenced by the inclusion of SC in the diet. The SC colonized the intestine of fingerlings fed with SC diet and was not observed in that fed with diets without probiotic. No differences were observed for the number of bacteria and total coliformes per g of intestinal content and per mL of water of the aquariums. The use of Saccharomyces cerevisiae as probiotic in rations of fingerlings of Nile tilapia (Oreochromis niloticus promoted the colonization of the intestine of the fishes, however, no influenced the productive performance and survival in a culture system with sanitary challenge.

  8. Nutritional aspects of nile tilapia (Oreochromis niloticus silage Aspectos nutricionais da silagem de tilápia-do-nilo (Oreochromis niloticus

    Directory of Open Access Journals (Sweden)

    Lia Ferraz de Arruda

    2006-12-01

    Full Text Available One third of the world's fishing produce is not directly used for human consumption. Instead, it is used for making animal food or is wasted as residue. It would be ideal to use the raw material thoroughly and to recover by-products, preventing the generation of residues. With the objectives of increasing the income and the production of the industry, as well as minimizing environmental and health problems from fish residue, chemical silage from Tilapia (Oreochromis niloticus processing residues was developed after homogenization and acidification of the biomass with 3% formic acid: propionic, 1:1, addition of antioxidant BHT and maintenance of pH at approximately 4.0. Analyses to determine the moisture, protein, lipids and ash were carried out. The amino acids were examined in an auto analyzer after acid hydrolysis, except for the tryptophan which was determined through colorimetry. The tilapia silage presented contents that were similar to or higher than the FAO standards for all essential amino acids, except for the tryptophan. The highest values found were for glutamic acid, lysine and leucine. The results indicate a potential use of the silage prepared from the Nile tilapia processing residue as a protein source in the manufacturing of fish food.Um terço da captura mundial de pescado não é empregada para o consumo direto na alimentação humana, segue para elaboração de rações ou é desperdiçada como resíduo. O ideal seria utilizar a matéria-prima em toda a sua extensão e recuperar os subprodutos, evitando a própria formação do resíduo. Com os objetivos de aumentar a receita e a eficiência de produção da indústria e, conseqüentemente, minimizar os problemas ambientais e de sanidade, provenientes do resíduo de pescado, procedeu-se à elaboração da silagem química do resíduo de beneficiamento de Tilápia-do-Nilo (Oreocrhromis niloticus após homogeneização e acidificação da biomassa com 3% de ácido f

  9. Molecular characterization and immune response to lipopolysaccharide (LPS) of the suppressor of cytokine signaling (SOCS)-1, 2 and 3 genes in Nile tilapia (Oreochromis niloticus).

    Science.gov (United States)

    Liu, Cai-Zhi; He, An-Yuan; Chen, Li-Qiao; Limbu, Samwel Mchele; Wang, Ya-Wen; Zhang, Mei-Ling; Du, Zhen-Yu

    2016-03-01

    Suppressor of cytokine signaling (SOCS) proteins are inverse feedback regulators of cytokine and hormone signaling mediated by the Janus kinase/signal transducer and activator of transcription (JAK/STAT) signaling pathway that are involved in immunity, growth and development of organisms. In the present study, three SOCS genes, SOCS-1, SOCS-2 and SOCS-3, were identified in an economically important fish, Nile tilapia (Oreochromis niloticus) referred to as NtSOCS-1, NtSOCS-2 and NtSOCS-3. Multiple alignments showed that, the three SOCS molecules share highly conserved functional domains, including the SRC homology 2 (SH2) domain, the extended SH2 subdomain (ESS) and the SOCS box with others vertebrate counterparts. Phylogenetic analysis indicated that NtSOCS-1, 2 and 3 belong to the SOCS type II subfamily. Whereas NtSOCS-1 and 3 showed close evolutionary relationship with Perciformes, NtSOCS-2 was more related to Salmoniformes. Tissue specific expression results showed that, NtSOCS-1, 2 and 3 were constitutively expressed in all nine tissues examined. NtSOCS-1 and 3 were highly expressed in immune-related tissues, such as gills, foregut and head kidney. However, NtSOCS-2 was superlatively expressed in liver, brain and heart. In vivo, NtSOCS-1 and 3 mRNA levels were up-regulated after lipopolysaccharide (LPS) challenge while NtSOCS-2 was down-regulated. In vitro, LPS stimulation increased NtSOCS-3 mRNA expression, however it inhibited the transcription of NtSOCS-1 and 2. Collectively, our findings suggest that, the NtSOCS-1 and 3 might play significant role(s) in innate immune response, while NtSOCS-2 may be more involved in metabolic regulation.

  10. Effect of synbiotics between Bacillus licheniformis and yeast extract on growth, hematological and biochemical indices of the Nile tilapia (Oreochromis niloticus

    Directory of Open Access Journals (Sweden)

    M.S. Hassaan

    2014-01-01

    Full Text Available Twelve practical diets were formulated to contain four levels of Bacillus licheniformis (0.0, 0.24 × 106, 0.48 × 106 and 0.96 × 106 CFU g−1, respectively, with three yeast extract levels (0%, 0.5% and 1%, respectively. Each diet was randomly assigned to duplicate groups of 50 Nile tilapia (Oreochromis niloticus (5.99 ± 0.03 g in 24 concrete ponds (0.5 m3 and 1.25 m depth for 12 weeks. Increasing dietary B. licheniformis levels in O. niloticus and yeast extract levels significantly (P < 0.01 improved growth performance and nutrient utilization. Supplementation of the experimental diets with, 0.48 × 106 CFU/g−1 and 1.0% yeast extract showed the best nutrient utilization compared to other treatments. All probiotic levels significantly (P < 0.01 increased chemical composition (P < 0.05 compared to the control group, while increasing yeast extract did not significantly alter chemical composition. Hematological indices, total protein and albumin of O. niloticus significantly increased while aspartate aminotransferase and alanine aminotransferase significantly (P < 0.01 decreased with an increase in B. licheniformis level up to 0.48 × 106 CFU g−1. Increasing levels of yeast extract had no effect on hematological parameters and the diets supplemented with 0.48 × 106 CFU g−1 and 0.5% yeast extract showed the highest hematological values.

  11. Effects of sub-lethal and chronic lead concentrations on blood and liver ALA-D activity and hematological parameters in Nile tilapia.

    Science.gov (United States)

    Dos Santos, Carlucio Rocha; Cavalcante, Ana Luiza Michel; Hauser-Davis, Rachel Ann; Lopes, Renato Matos; Mattos, Rita De Cássia Oliveira Da Costa

    2016-07-01

    Liver and blood δ-aminolevulinic acid dehydratase (ALA-D) inhibition by exposure to sub-lethal lead concentrations over time in Nile tilapia (Oreochromis niloticus) were investigated. All three lead concentrations (1mgkg(-1), 10mgkg(-1) and 100mgkg(-1)) significantly inhibited ALA-D activity in blood (319±29.2; 180±14.6 and 172±19µmols(-1)h(-1)L(-1) respectively) and liver (302±5.84; 201±41.4 and 93±22.1µmols(-1)h(-1)L(-1)) 24h after injection relative to controls (blood: 597±37.0µmols(-1)h(-1)L(-1); liver: 376±23.1µmols(-1)h(-1)L(-1)). Blood ALA-D was greatly inhibited in all but the highest lead dose. Fish were then exposed to 1mgkg(-1) lead for 9 days, and presented short-term hyperglycemia, decreased hemoglobin and hematocrit values and time-dependent blood ALA-D activity inhibition, corroborating blood ALA-D activity as being more suitable for investigating lead effects, showing dose and time-dependent ALA-D inhibition after lead exposure. The results of the present study also demonstrated that fish size affects blood ALA-D activity, as fish from the 24-h assay, which were slightly smaller (approximately 200g), showed higher ALA-D inhibition in response to lead exposure when compared to the fish from the 9-day assay (approximately 500g). Thus, fish size should always be taken into account both in the field and in laboratory settings, and efforts should be made to obtain uniform fish size samples for biomarker studies.

  12. Apparent and true digestibility of protein and amino acid in feedstuffs used in Nile Tilapia feed as determined by the technique of dissection

    Directory of Open Access Journals (Sweden)

    Felipe Barbosa Ribeiro

    2012-05-01

    Full Text Available The objective of this study was to determine the coefficients of apparent and true digestibility of protein and amino acids of five feedstuffs (corn, wheat bran, soybean meal, corn gluten meal and fish meal in 900 sex-reversed Nile tilapia (Oreochromis niloticus of the Thai strain during the growth phase, with an initial weight of 315±8.45 g. A total of 750 fish were distributed according to a randomized block design (repetitions in time into five treatments with six replicates of 25 fish each. The remaining 150 fish were fed a protein-free diet to measure endogenous protein and amino acid losses in order to determine the true digestibility of these components. Each tested diet contained a single protein source, which consisted of one of the evaluated feedstuffs. Digestibility was indirectly estimated using chromic oxide at 0.50% as marker. Digesta was collected from the last 5 cm of the distal intestine (between the ileal-rectal valve and the anus using the dissection technique. Apparent digestibility coefficients of protein and amino acids were, on average, 74.69 and 73.62% for corn, 73.74 and 72.81% for wheat bran, 86.01 and 84.66% for soybean meal, 85.19 and 84.29% for corn gluten meal, 76.74 and 75.56% for fish meal, respectively. True digestibility coefficients of protein and amino acids were, on average, 85.21 and 83.97% for corn, 84.41 and 83.74% for wheat bran, 87.22 and 87.51% for soybean meal, 87.97 and 87.34% for corn gluten meal, and finally 79.58 and 78.44% for fish meal, respectively.

  13. Direct and indirect effects of measures and reasons morphometric on the body yield of Nile tilapia, Oreochromis niloticus - doi: 10.4025/actascianimsci.v35i4.19807

    Directory of Open Access Journals (Sweden)

    Carlos Cicinato Vieira Melo

    2013-10-01

    Full Text Available The study was carried out with the objective of verifying which measures and morphometric ratios are more directly related to the body yield of Nile tilapia, Oreochromis niloticus, in two weight classes. Data were analyzed from 257 specimens of tilapia divided into two weight classes: p1 = 400 to 599 g and p2 = 600 to 900 g. The morphometric measurements standard length (SL, head length (HL, body height (BH and body width (BW, and the ratios of these measures (HL / SL, BH / SL, BW / SL, HL / BH, BW / BH, BW / HL were evaluated. The following body yields were calculated: carcass (RCAR, fillet (RFILE and head (RCAB. The data were initially submitted to the "stepwise" procedure to eliminate problems of multicollinearity among the morphometric variables, then the correlations between the dependent variables (body yield and the independent variables (measured and morphometric relationships were calculated. Later, these correlations were divided into direct and indirect effects through path analysis, and the direct and indirect contributions of each variable measured in percentage terms. The morphometric ratio BW/HL, for both weight classes, was the variable most highly correlated and with the highest direct effect on RFILE and RCAB, showing to be the most important morphometric variable studied for tilapia carcass trait determination.   

  14. Prevalence and diversity of fish-borne zoonotic trematodes in tilapia (Oreochromis niloticus) culture in Guangdong, China

    DEFF Research Database (Denmark)

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

    ), and Carassius auratus (4).The FZT species recovered were mainly Haplorchis taichui, and H. pumilio along with some unknown species whose identifications are still being determined. Subsequently a cross-sectional survey for the prevalence and diversity of FZT in tilapia culture systems was conducted in Guangdong...... Province during August-October 2011. A total of 389 tilapias sized 2.33-1450.00 g were collected from 30 farms, and examined for FZT metacercariae by the pepsin digestion method. Ten percent of the farms surveyed had fish with FZT infections. The overall FZT prevalence in fish was 1.5% and the infection...

  15. Exploring the trophic structure in organically fertilized and feed-driven tilapia culture environments using multivariate analyses

    NARCIS (Netherlands)

    Muendo, P.N.; Milstein, A.; Dam, A.; Gamal, N.E.; Stoorvogel, J.J.; Verdegem, M.C.J.

    2006-01-01

    Reports of similar yields in manure and feed-driven tilapia culture environments raise questions on food utilization in these environments. The possibility that similar production rates are because of utilization of different foods was investigated using exploratory techniques of multivariate analys

  16. 甲基睾丸酮在罗非鱼体内的消解规律%Elimination of 17a-methyltestosterone Fed to Adult Nile Tilapia Oreochromis niloticus(L.)

    Institute of Scientific and Technical Information of China (English)

    邹琴

    2012-01-01

    研究了在现实养殖环境中,采用含甲基睾丸酮200 mg/kg的饲料持续投喂罗非鱼成鱼3 d,随后将其转移到养殖池塘中体内甲基睾丸酮的消解规律。应用高效液相色谱法检测不同时间肌肉和鱼皮中甲基睾丸酮的残留量,结果发现肌肉和鱼皮中甲基睾丸酮残留量趋势为指数递减,组织中甲基睾丸酮残留量在停药后1164 h,即49 d时才无检出。%Studies were conducted on the Elimination of 17a-methyltestosterone(MT) in adult Nile tilapia Oreochromis niloticus(L.) that received dietary of MT to induce growth under aquaculture model.Nile tilapia were fed on a diet containing MT(200 mg/kg) for 3 d,then transferd to a pond with normal feed.In the latter days,MT residues in muscle and skin were measured by high performance liquid chromatography(HPLC),DAS drug dynamics software combines EXCEL 2003 statistical software were applied to the data processing and analysis in order to get the elimination rule of MT in tilapia muscle and skin.The results showed that,the elimination of MT in muscle and skin were relatively slow following the withdrawal for exponential decline,and ended approximately in 1164 h,49 d withdrawal.

  17. Farinha de peixe em rações para alevinos de tilápia do Nilo, Oreochromis niloticus (L., linhagem tailandesa Fishmeal in the diets of Nile tilapia fingerlings Oreochromis niloticus (L., Thai strains

    Directory of Open Access Journals (Sweden)

    Eliana Maria Galdioli

    2001-05-01

    Full Text Available O objetivo desse experimento foi determinar o nível adequado de incorporação de farinha de peixe (FP em rações para alevinos de tilápia do Nilo, Oreochromis niloticus (Perciformes, Cichlidae linhagem tailandesa. Foram distribuídos 300 animais com peso inicial médio de 0,42 ± 0,01 g, em 25 tanques-rede, em um delineamento em blocos casualizados com cinco tratamentos (0, 4, 8, 16 e 20% de FP na ração e cinco repetições. Foi observado efeito quadrático (p 0,05 dos níveis da FP sobre a sobrevivência e rendimento de carcaça. Conclui-se que o nível adequado de inclusão de farinha de peixe em rações para alevinos de tilapia do Nilo é de 12,15%.The adequate fishmeal (FM inclusion level in diets for Nile tilapia fingerlings, Oreochromis niloticus (Perciformes, Cichlidae Thai strain, is provided. Three hundred fishes with initial mean average weight of 0.42 ± 0.01 g were distributed in 25 net ponds in a randomized block design with five treatments (0, 4, 8, 16 e 20% of FM in diet and five repetitions. Quadratic effect (p 0,05 did not affect survival and carcass yield. It may be concluded that the appropriate fishmeal inclusion is 12.15% in diets for Nile tilapia fingerlings.

  18. Identification of immunoreactive proteins of Streptococcus agalactiae isolated from cultured tilapia in China.

    Science.gov (United States)

    Liu, Guangjin; Zhang, Wei; Lu, Chengping

    2013-12-01

    Streptococcus agalactiae (Group B streptococcus, GBS) is an important zoonotic pathogen that can cause lethal infections in humans and animals, including aquatic species. Immunoreactive proteins of the S. agalactiae strain, GD201008-001, isolated from cultured tilapia in China, were screened by immunoproteomics using hyperimmune sera, convalescent guinea pig sera and GD201008-001-infected tilapia antisera as primary detection antibodies. A total of 16 different proteins were identified including 13 novel immunoreactive proteins of S. agalactiae. Four proteins, serine-rich repeat glycoprotein 1, branched-chain alpha-keto acid dehydrogenase (BKD) subunit E2, 5'-nucleotidase family protein and ornithine carbamoyltransferase, were shown to react with the three types of sera and thus were considered to represent novel S. agalactiae vaccine candidate antigens. Our findings represent the basis for vaccine development for piscine S. agalactiae and are necessary for understanding virulence factors and immunogenicity of S. agalactiae with different hosts.

  19. STUDY ON THE HISTOCHEMICAL PROPERTY OF THE MAST CELLS IN THE DIGESTIVE TRACT OF NILE TILAPIA%尼罗罗非鱼消化道肥大细胞的组化性质

    Institute of Scientific and Technical Information of China (English)

    林旋; 林树根; 王全溪; 陈梅芳; 严美姣; 王寿昆

    2011-01-01

    实验采用改良甲苯胺蓝(MTB)、阿利新蓝-沙黄(AB/SO)、甲基绿-派洛宁(MG-P)、天青Ⅱ-伊红-瑞氏混合液和硫堇5种组化染色法,对尼罗罗非鱼(Nile tilapia)消化道组织中的肥大细胞(Mast cell,MC)组化性质进行研究.尼罗罗非鱼的食管、胃及小肠壁内均显示有肥大细胞,在食管和胃的切片标本上肥大细胞主要分布在黏膜固有层和胃腺体之间.在肠道中的肥大细胞主要分布在黏膜固有层和肠上皮下方,少量肥大细胞存在于黏膜下层结缔组织中.细胞呈圆形、椭圆形,也有长梭形的.而且肥大细胞有沿血管分布的特点.5种组化染色结果表明:AB/SO、MTB和MG-P显示的MC效果较好,尤其AB/SO染色效果最好,肥大细胞轮廓清楚,胞质颗粒较清晰;尼罗罗非鱼肥大细胞胞浆颗粒都呈红色,即肥大细胞胞浆主要含肝素,不含组胺.天青Ⅱ-伊红-瑞氏混合液染色效果也很好,但被染的肥大细胞较少;80%乙醇硫堇染色,在尼罗罗非鱼消化道各段组织中均未能鉴定出肥大细胞.尼罗罗非鱼消化道肥大细胞大多分布于浅层的黏膜或血管、腺体周围的结缔组织等易表露于环境抗原的位点.罗非鱼消化道黏膜层结缔组织中的肥大细胞与大多数脊椎动物的肥大细胞一样,具有沿血管分布的特性,说明硬骨鱼的肥大细胞如哺乳动物肥大细胞一样与血管有着密切的关系.%Five healthy nile tilapia (average weight 500g) were bought. After executing, the esophagus, stomachus (stomachus fundus, stomachus pylorus and stomachus cardiacus), small intestine (foregut, midgut and hindgut) were respectively fixed in the Carnoy solution (60% dehydrate alcohol, 30% chloroform and 10% glacial acetic acid), continuously embedded and sliced with 6μm. Toluidine blue staining (MTB), Alcian blue Safranin O staining (AB/SO),methyl green-Pyronine staining (MG-P), Azure II - Eosin - Wright mixture staining and Thionine

  20. Tilapia by-product meal in rations for Nile tilapia (Oreochromis niloticus fingerlings/ Farinha de resíduos da filetagem de tilápia em rações para alevinos de tilápia do Nilo (Oreochromis niloticus

    Directory of Open Access Journals (Sweden)

    Adilson Reidel

    2005-06-01

    Full Text Available Objectifying to evaluate the inclusion of tilapia processing residues (FT in the feeding of Nile tilapia (Oreochromis niloticus fingerlings, 125 Nile tilapia fingerlings (with average initial weight of 0.72±0.19g were distributed in a completely randomized design with five treatments and five repetitions in 25 aquariums (30L. The rations were formulated to contain 0, 5, 10, 15% of FT and 0% FT plus methionine (0+met. Isoproteics, isocalcitics, isophosphorics and isoenergetics diets were used. After 28 days of experiment, final weight (PF, weight gain (GP, feed conversion ratio (CA and survival (SO, were evaluated. No differences were observed (P>0.05 for the studied parameters. It was concluded that the FT can be used up to 15% in substitution to the soybean meal in the diet of nile tilapia fingerlings.Objetivando avaliar a inclusão de farinha de resíduos da filetagem de tilápias (FT na alimentação de alevinos de tilápia do Nilo (Oreochromis niloticus, foram utilizados 125 alevinos de tilápia do Nilo com peso inicial médio de 0,72±0,19g, distribuídos em um delineamento inteiramente casualizado com cinco tratamentos e cinco repetições, em 25 aquários (30L cada. As rações foram formuladas de forma a conterem 0, 5, 10, 15% de FT e 0% de FT mais metionina (0+met, sendo as mesmas isoenergéticas isoprotéicas, isocalcíticas e isofosfóricas. Após 28 dias de experimento foram avaliados as médias de peso final (PF, ganho de peso (GP, conversão alimentar aparente (CA e sobrevivência (SO. Não foram observadas diferenças (P>0,05 entre os parâmetros avaliados. Conclui-se que a FT pode ser utilizada em até 15% em substituição ao farelo de soja em rações para alevinos de tilápia sem causar prejuízo ao seu desempenho.

  1. Partial and total substitution of soy oil for tilapia oil in rations for larvae of Nile tilapia (Oreochromis niloticus / Substituição parcial e total do óleo de soja pelo óleo de tilápia em rações para larvas de tilápia do Nilo (Oreochromis niloticus

    Directory of Open Access Journals (Sweden)

    Adilson Reidel

    2008-08-01

    Full Text Available The present experimentwas undertaken out to evaluate the performance and the survival of Nile tilapia (Oreochromis niloticus in the sexual reversion phase. The fish were fed with rations with different levels of tilapia oil in substitution of the soy oil. 7 larvae, with average weight of 0,012 ±0,002 g e 0,931 ±0,144 cm, respectively were used. Fish were distributed in 25 aquariuns with 15 larvae in an entirely randomly design with 5 treatments and 5 repetitions. The rations contained levels of 0,0; 2,5; 5,0; 7,5 e 10,0% of tilapia oil inclusion. Rations with 3.800 Kcal/kg of digestible energy and 38.6% of digestible protein were used. Differences for the final weight, final length, survival and condition factor were not observed. The tilapia oil can totaly substitute the soy oil in Nile tilapia larvae diets during sexual reversion.O presente experimento teve por objetivo avaliar o desempenho e a sobrevivência da tilápia do Nilo (Oreochromis niloticus na fase de reversão sexual, alimentadas com rações contendo diferentes níveis de inclusão de óleo de tilápia substituindo o óleo de soja. Foram utilizadas 7 larvas, com peso e comprimento médio de 0,012 ±0,002 g e 0,931 ±0,144 cm, respectivamente, distribuídas em 25 aquários com 15 larvas em um delineamento inteiramente casualizado com 5 tratamentos e 5 repetições. As rações continham níveis de 0,0; 2,5; 5,0; 7,5 e 10,0% de inclusão de óleo de tilápia, substituindo 100% do óleo de soja. As rações apresentavam 3.800Kcal/kg de energia digestível e 38,6 % de proteína digestível. Não foram observadas diferenças para o peso final, comprimento final, sobrevivência e fator de condição não apresentaram diferença. O óleo de tilápia pode substituir totalmente o óleo de soja para larvas de tilápia do Nilo durante a reversão sexual.

  2. Silagem de peixe em ração artesanal para tilápia-do-nilo Fish silage in farm-made feed for Nile tilapia

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    Eduardo Gianini Abimorad

    2009-05-01

    Full Text Available O objetivo deste trabalho foi avaliar o emprego de ração artesanal à base de silagem de resíduo da filetagem de pescado na criação de tilápia-do-nilo (Oreochromis niloticus. Dois mil e setenta juvenis de tilápia revertidos (83,1 g foram distribuídos em seis viveiros escavados com 230 m² cada um, na densidade de estocagem de 1,5 peixe por metro quadrado, em delineamento inteiramente casualizado com dois tratamentos (ração artesanal e ração comercial e três repetições. Foram analisados os parâmetros de desempenho produtivo (sobrevivência, ganho em peso, conversão alimentar aparente, taxa de crescimento específico e coeficiente de variação do peso final, as variáveis de qualidade da água (oxigênio dissolvido, transparência e fósforo e nitrogênio total, o custo de arraçoamento e a composição corporal. Não houve diferença significativa entre as rações para os parâmetros de desempenho produtivo. Verificou-se maior eutrofização da água dos viveiros onde os peixes receberam ração artesanal. O custo por quilograma de peixe produzido com ração artesanal (R$ 1,07 foi aproximadamente 42% menor que o de peixe produzido com ração comercial (R$ 1,86. Os peixes alimentados com ração artesanal tiveram teor de lipídios significativamente menor na carcaça.The objective of this work was to evaluate the use of a farm-made feed based on silage of fish filleting residues for Nile tilapia (Oreochromis niloticus farming. Two thousand and seventy masculinized tilapia juveniles (83.1 g were distributed into six ponds (230 m², at a stocking density of 1.5 fish per square meter. The experimental design was a completely randomized with two treatments (farm-made and commercial feeds and three replicates. The performance parameters analyzed were survival, weight gain, apparent feed conversion, specific growth rate, and final weight coefficient of variation. The water quality variables analyzed were dissolved oxygen

  3. Somatic growth effects of intramuscular injection of growth hormone in androgen-treated juvenile Nile tilapia, Oreochromis niloticus (Perciformes: Cichlidae

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    Marco A. Liñán-Cabello

    2013-03-01

    Full Text Available Little is known about the effects of the interaction of growth hormone (GH with 17 a-methyltestosterone (17-MT during fish growth. We evaluated this in the present study to assess the effect on fish growth. Fish in two batches of juvenile tilapia (Oreochromis niloticus (approximately 5.0cm in length were randomly assigned in triplicate to three treatments and a control group, distributed among 12 fiberglass tanks of 1 000L capacity (50 fish per tank in an experiment covering a period of six weeks. The experimental groups were: a fish treated with 17-MT and GH in mineral oil (RGH; b fish treated with 17-MT and mineral oil without the addition of GH (R; c fish treated with GH in mineral oil but not 17-MT (NGH; and d fish of the control group, which were treated with mineral oil but not 17-MT or GH (N. The GH was injected into the fish at a rate of 0.625mg/g body weight. Morphometric data were recorded at the beginning of the experiment (T and at 15, 30 and 45 days (T, T and T, and various indicators of growth were assessed: condition factor (K; survival percentage (S, feed conversion rate (FCR, percentage weight gain (WG and (v daily weight gain. The optimum dietary level was calculated assuming 5% food conversion to total weight in each group. During the experiment, the fish were provided with a commercial food containing 45% protein. The data showed that GH injection resulted in a greater weight gain in fish treated with 17-MT (the RGH treatment group, being particularly significant increase in weight during T and T (p<0.05. High values of K were found in the R and RGH treatments during the initial days of the experiment, which may have been a consequence of the better nutritional status affecting both weight gain and growth in body length, as a result of the additive effects of 17-MT and GH. The fish in groups not treated with 17-MT and treated with 17-MT and added GH showed greater increases in WG per day, higher K values and lower FCRs than

  4. Somatic growth effects of intramuscular injection of growth hormone in androgen-treated juvenile Nile tilapia, Oreochromis niloticus (Perciformes: Cichlidae

    Directory of Open Access Journals (Sweden)

    Marco A. Liñán-Cabello

    2013-03-01

    Full Text Available Little is known about the effects of the interaction of growth hormone (GH with 17 a-methyltestosterone (17-MT during fish growth. We evaluated this in the present study to assess the effect on fish growth. Fish in two batches of juvenile tilapia (Oreochromis niloticus (approximately 5.0cm in length were randomly assigned in triplicate to three treatments and a control group, distributed among 12 fiberglass tanks of 1 000L capacity (50 fish per tank in an experiment covering a period of six weeks. The experimental groups were: a fish treated with 17-MT and GH in mineral oil (RGH; b fish treated with 17-MT and mineral oil without the addition of GH (R; c fish treated with GH in mineral oil but not 17-MT (NGH; and d fish of the control group, which were treated with mineral oil but not 17-MT or GH (N. The GH was injected into the fish at a rate of 0.625mg/g body weight. Morphometric data were recorded at the beginning of the experiment (T and at 15, 30 and 45 days (T, T and T, and various indicators of growth were assessed: condition factor (K; survival percentage (S, feed conversion rate (FCR, percentage weight gain (WG and (v daily weight gain. The optimum dietary level was calculated assuming 5% food conversion to total weight in each group. During the experiment, the fish were provided with a commercial food containing 45% protein. The data showed that GH injection resulted in a greater weight gain in fish treated with 17-MT (the RGH treatment group, being particularly significant increase in weight during T and T (pActualmente, durante el crecimiento de los peces existe poco conocimiento sobre los efectos de la interacción de la hormona del crecimiento (HC con 17 α-metiltestosterona (17-MT. En el presente estudio los peces en dos lotes de tilapia (Oreochromis niloticus (5.0cm de longitud, fueron asignados al azar por triplicado a tres tratamientos y un grupo control, distribuidos en 12 tanques de fibra de vidrio de 1 000 litros (50 peces

  5. THE GROWTH OF JAPANESE AND WEST NILE ENCEPHALITIS VIRUSES IN TISSUE CULTURES,

    Science.gov (United States)

    extinguishing it with a homologous immune serum. In the HeLa cells a specific cytopathogenic effect was registered after six cultural passages of the strain R...1. The cytopathogenic effect was retained in subinoculation. The West Nile encephalitis virus induced a cytopathogenic effect in the HeLa cells from

  6. 甲磺隆在尼罗罗非鱼体内蓄积的研究%Accumulation of metsulfuron- methyl residues in Nile tilapia Oreochromis niloticus

    Institute of Scientific and Technical Information of China (English)

    邢殿楼; 王华; 王丽; 王伟; 雷衍之

    2011-01-01

    在室外人工水生生态试验装置中,采用放射性同位素示踪技术研究了14C标记的甲磺隆在尼罗罗非鱼Oreochromis niloticus体内的蓄积过程.结果表明:尼罗罗非鱼不同组织器官对甲磺隆的蓄积量存在一定差异,虽然鱼体肌肉中的放射性比活度在各器官中最低,但肌肉对放射性标记物的蓄积量最高;甲磺隆在鱼体不同组织器官内的蓄积与排出达到动态平衡所需的时间不同,鱼内脏中达到平衡时所需时间最短,而鱼躯干部所需时间最长,鱼内脏对甲磺隆表现为清除排出,而鱼头部和躯干部对甲磺隆均表现为先吸收蓄积,然后再逐渐转化为清除排出.%Accumulation of metsulfuron - methyl residues in Nile tilapia Oreochromis niloticus was studied under simulated pond conditions by 14C isotopic tracer technique. The quantity of metsulfuron - methyl residues were found different in the fish tissues. Compared with other tissues of fish, the maximal amount of accumulated metsulfuron - methyl was observed in the flesh, even though the minimal concentration of metsulfuron - methyl residues in the same tissue. The dynamic of metsulfuron - methyl residues in the fish tissues demonstrated that the duration for reaching the balance between the accumulation and elimination was found different. The less required duration was found in the fish viscera and more required duration in the truck for the balance. The tendency of metsulfuron methyl residues in fish viscera was expressed as elimination, whereas the fish head and truck showed accumulation at the initial stages of the experiment, and then it gradually changed to elimination.

  7. Farelo de soja na alimentação de tilápias-do-nilo durante o período de reversão sexual Soybean meal in Nile tilapia diets during the sexual reversion period

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    Fábio Meurer

    2008-05-01

    Full Text Available Foram utilizadas 800 larvas com 2 dias de idade com o objetivo de testar o uso de farelo de soja em rações para tilápias-do-nilo durante o período de reversão sexual (30 dias. O experimento foi conduzido segundo delineamento em blocos casualizados com quatro tratamentos e quatro repetições, no qual um tanque-rede com 50 larvas correspondeu a uma unidade experimental. Os tratamentos consistiram de rações isoprotéicas e isoenergéticas (38,6% de proteína digestível e 3.800 kcal/kg de energia digestível com 0, 16, 34 ou 42% de farelo de soja. O aumento no nível de farelo de soja teve efeito linear positivo sobre os valores de peso e comprimento finais médios, mas não afetou a condição corporal e os índices de sobrevivência. Recomenda-se incluir o farelo de soja em níveis de até 42% na ração de tilápias-do-nilo na fase de reversão.Eight hundred Nile tilapia larvae with two days old were used to evaluate the inclusion of soybean meal in diets fed Nile tilapia during the sex reversion period (30 days. The experiment was analyzed as a completely randomized blocks, with four treatments and four replications. A net tank with 50 larvae was considered an experimental unit. The treatments were formulated to be isoprotein and isonitrogenous (38.6% of digestible protein and 3,800 kcal/kg of digestible energy, with increasing levels of soybean meal inclusion 0, 16, 34 and 42%. Average final weight and length linearly increased as the dietary soybean meal levels increased. No treatment effect on survival and body condition was observed. It is recommend to include up to 42% of soybean meal in Nile tilapia diets in the sexual reversion phase.

  8. CRESCIMENTO DE TILÁPIA-DO-NILO ALIMENTADA COM PEIXES MARINHOS PROVENIENTES DA PESCA DO CAMARÃO GROWTH IN NILE TILAPIA FED WITH MARINE FISH FROM SHRIMP FISHERY

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    Jullyermes Araújo Lourenço

    2007-07-01

    Full Text Available O objetivo deste trabalho foi avaliar o uso de peixes marinhos no crescimento de tilápia-do-Nilo, Oreochromis niloticus. Desenvolveu-se o experimento em delineamento inteiramente casualizado com três tratamentos (ração para peixes com 28% de PB, Pellona harroweri e Pomadasys croco, três repetições cada. Utilizaram-se 63 peixes, com peso médio inicial de 3,059±0,846 g e 44,1±4,0 mm para o tratamento com ração, 3,015±0,892 g e 44,6±4,5 mm para o tratamento com P. harroweri e 2,736±0,803 g e 43,6±4,5 mm para o tratamento com P. croco, distribuídos homogeneamente em nove tanques de alvenaria de 2 m3 cada, contendo sete peixes por tanque. Após 91 dias, os resultados indicaram que as dietas com ração resultaram em melhores ganhos em peso e crescimento específico (P < 0,05. A tilápia-do-Nilo, mesmo sendo uma espécie omnívora, aceitou bem as dietas compostas pelas espécies de peixes marinhos utilizadas neste trabalho. PALAVRAS-CHAVES: Alimentação de peixes, aqüicultura alternativa, Oreochromis niloticus. The objective of this work was to verify the use of marine fish on Nile tilapia, Oreochromis niloticus, growth performance. Sixty three Nile tilapia juveniles, with an average weight and length of 3.059±0.846 g and 44.1±4.0 mm to treatment with ration, 3.015±0.892 g and 44.6±4.5 mm to treatment with Pellona harroweri and 2.736±0.803 g and 43.6±4.5 mm to treatment with Pomadasys croco, were stocked into nine floating cages with 2 m3 (seven fish per cage, in a complete randomized design with three treatments (ration to fish with 28% PB, P. harroweri and P. croco, in three replicates each. After ninety one days, results showed that diet with ration produced a better weight gain, specific growth rate (P < 0.05. The Nile tilapia is an omnivorous species, but fed on marine fish used in this work. KEY- WORDS: Alternatives aquaculture, feeding of fish, Oreochromis niloticus.

  9. Quantitative and qualitative analyses of the bacterial microbiota of tilapia (Oreochromis niloticus) cultured in earthen ponds in the Philippines.

    Science.gov (United States)

    Pakingking, Rolando; Palma, Peter; Usero, Roselyn

    2015-02-01

    The quantity and composition of the bacterial microbiota in the rearing water, sediment, gills and intestines of tilapia Oreochromis niloticus collected every 2 weeks from Day 30 to Day 120 after stocking for grow-out culture in 6 earthen brackish water ponds in the Philippines were examined. The total heterotrophic aerobic bacterial counts obtained in the water, sediment, gills and intestines of tilapia ranged from 10(3) to 10(4) c.f.u. ml(-1), 10(3)-10(5), 10(5)-10(7) and 10(4)-10(7) c.f.u. g(-1), respectively. In terms of composition, a total of 20 bacterial genera and 31 species were identified with the preponderance of gram-negative bacteria constituting 84 % of all bacterial isolates examined. Aeromonas hydrophila, Bacillus spp., Plesiomonas shigelloides, Shewanella putrefaciens, Pseudomonas fluorescens, Staphylococcus spp. and Vibrio cholerae were the dominant bacteria identified in the gills and intestine of tilapia. These bacteria also dominated in the pond sediment and rearing water, except for the nil isolation of S. putrefaciens and V. cholerae in the water samples examined, indicating that resident bacteria in the pond water and sediment congruently typify the composition of bacterial microbiota in the gills and intestine of tilapia which under stressful conditions may propel the ascendance of disease epizootics.

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

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    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.

  11. Eficácia do mentol como anestésico para juvenis de tilápia-do-nilo (Oreochromis niloticus Menthol efficiency as anesthetic for juveniles Nile tilapia Oreochromis niloticus

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    L.N. Simões

    2009-06-01

    concentrations indicating a stress response of the fish. Thus menthol is an ineffective anesthetic to juveniles tilapia during routine procedures in fish culture.

  12. Acute inflammatory response in Nile tilapia fed probiotic Lactobacillus plantarum in the diet - doi: 10.4025/actascibiolsci.v33i3.8011 Acute inflammatory response in Nile tilapia fed probiotic Lactobacillus plantarum in the diet - doi: 10.4025/actascibiolsci.v33i3.8011

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    Celso Pilati

    2011-07-01

    Full Text Available The present study evaluated the acute inflammatory response induced by carrageenin (500 µg injected in the swim bladder of Nile tilapia, after fed or not probiotic supplemented diet. Fifty four fish were distributed in six treatments and three replicates: Group A: Fish fed unsupplemented diet: 0.5 mL saline-injected fish; fish injected with 500 µg carrageenin diluted in 0.5 mL saline; Non-injected. Group B: Fish fed probiotic supplemented diet: saline-injected fish; carrageenin-injected fish; Non-injected. Fifteen days after feeding the fish were injected with carrageenin or saline. After six hours, inflammatory exudate was collected, as well as the blood for hematocrit, red blood cell (RBC and white blood cell (WBC counts, differential count of leucocytes and phagocytic activity in the blood. Supplementation with probiotic did not influence the RBC, hematocrit and the numbers of lymphocytes and basophils in the blood. The number of neutrophils was significantly higher in supplemented fish injected with carrageenin. Glucose concentration in supplemented and non-injected fish was higher than that observed in the saline injected ones. Probiotic potentialized the migration of cells to the inflammatory focus in the animals injected with the carrageenin irritant. In fish injected with saline and carrageenin occurred the greatest phagocytic activity in the blood in relation to those treatments.The present study evaluated the acute inflammatory response induced by carrageenin (500 µg injected in the swim bladder of Nile tilapia, after fed or not probiotic supplemented diet. Fifty four fish were distributed in six treatments and three replicates: Group A: Fish fed unsupplemented diet: 0.5 mL saline-injected fish; fish injected with 500 µg carrageenin diluted in 0.5 mL saline; Non-injected. Group B: Fish fed probiotic supplemented diet: saline-injected fish; carrageenin-injected fish; Non-injected. Fifteen days after feeding the fish were injected

  13. 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...

  14. Valor nutricional do farelo de algodão para alor a tilápia do nilo (Oreochromis niloticus = Nutritional value of cottonseed meal for Nile tilapia (Oreochromis niloticus

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    Geisa Karine Kleemann

    2009-01-01

    Full Text Available Determinou-se a composição química dos farelos de algodão 28,0; 38,0 e 46,0% de proteína bruta e os coeficientes de digestibilidade aparente (CDA pela tilápia do Nilo da matéria seca, proteína, aminoácidos, energia, lipídeo e minerais. Os CDA foram determinados, usando-se dieta-referência purificada, contendo 0,1% do indicador óxido de crômio-III. As rações-teste continham 60,0% da dieta-referência e 40,0% dos alimentos em estudo. Os resultados mostraram diferença (p Cottonseed meals (CSM with different protein levels (35, 39 and 40% were evaluated to determine their chemical composition and measure apparent digestibility coefficients (ADC of dry matter, protein, amino acids, energy, lipid and minerals for Nile tilapia. Apparent digestibility coefficients were determined using a reference purified diet containing 0.1% of chromic oxide indicator, and test diets contained 60% of reference diet and 40% of test ingredients. Results showed that apparent digestibility coefficients of cottonseed meals were different (p < 0.05. The apparent digestibility coefficients were: dry matter, 53.45-54.32%; crude protein, 71.56-74.81%; energy, 53.80-58.60%; lipid, 85.37- 89.11%; phosphorus, 33.75-34.50%; calcium, 41.21-43.75%; iron, 62.02-79.85%; zinc, 0- 67.41%; copper, 13.37-14.27%; essential amino acids, 71.39-79.17%; and non-essentialamino acids, 77.08-82.58%. The ADC of protein did not reflect the majority of amino acids ADC showing variation in individual digestibility of amino acids and among cottonseed meals. Cottonseed meal can be used as protein succedaneum in Nile tilapia diets.

  15. A Comparison of the Beneficial Effects of Live and Heat-Inactivated Baker's Yeast on Nile Tilapia: Suggestions on the Role and Function of the Secretory Metabolites Released from the Yeast.

    Science.gov (United States)

    Ran, Chao; Huang, Lu; Liu, Zhi; Xu, Li; Yang, Yalin; Tacon, Philippe; Auclair, Eric; Zhou, Zhigang

    2015-01-01

    Yeast is frequently used as a probiotic in aquaculture with the potential to substitute for antibiotics. In this study, the involvement and extent to which the viability of yeast cells and thus the secretory metabolites released from the yeast contribute to effects of baker's yeast was investigated in Nile tilapia. No yeast, live yeast or heat-inactivated baker's yeast were added to basal diets high in fishmeal and low in soybean (diet A) or low in fishmeal and high in soybean (diet B), which were fed to fish for 8 weeks. Growth, feed utilization, gut microvilli morphology, and expressions of hsp70 and inflammation-related cytokines in the intestine and head kidney were assessed. Intestinal microbiota was investigated using 16S rRNA gene pyrosequencing. Gut alkaline phosphatase (AKP) activity was measured after challenging the fish with Aeromonas hydrophila. Results showed that live yeast significantly improved FBW and WG (P yeast). No significant differences were observed between inactivated yeast and control. Live yeast improved gut microvilli length (P yeast did not. The hsp70 expression level in both the intestine and head kidney of fish was significantly reduced by live yeast (P yeast. Live yeast but not inactivated yeast reduced intestinal expression of tnfα (P Intestinal Lactococcus spp. numbers were enriched by both live and inactivated yeast. Lastly, both live and inactivated yeast reduced the gut AKP activity compared to the control (P yeast. Nevertheless, secretory metabolites were the major contributing factor towards improved gut microvilli morphology, relieved stress status, and reduced intestinal inflammation of Nile tilapia fed diets supplemented with baker's yeast.

  16. Pengimbuhan Ragi Roti dalam Pakan Meningkatkan Respons Imun Nonspesifik dan Pertumbuhan Ikan Nila (SUPPLEMENTATION OF BAKER’S YEAST IN FEED ENHANCE NONSPECIFIC IMMUNE RESPONSE AND GROWTH OF NILE TILAPIA

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    Henky Manoppo

    2015-08-01

    Full Text Available A study was carried out to evaluate the efficacy of Baker’s yeast (Saccharomyces cereviciae to enhancenonspecific immune response and growth of Nile tilapia fish (Oreochromis niloticus. The fish were obtainedfrom Freshwater Hatchery Tateli (BP3I, Marine and Fisheries Office, North Sulawesi. After acclimatizationfor two weeks in 1000 L fiberglass tank, fish with an average weight of 9 g were put in five 45 L-aquaria ata density of 15 fish/aquarium. During the experiment, fish were fed with feed pellet supplemented withfive different doses of baker’s yeast (10, 20, 30, 40 g yeast/kg pellet for four consecutive weeks at 5% bw/day, twice a day. Fish in different aquarium received different dose of baker’s yeast. Immune parametersincluding total leucocyte count and phagocytosis activity and growth of fish were measured at two weeksinterval. After four weeks of feeding, total leucocyte count and phagocytosis activity of phagocyte cells offish fed pellet supplemented with 10 g yeast/kg pellet increased significantly as compared to that ofcontrol fish (p<0.01. Growth of fish fed pellet supplemented with 10 g yeast/kg pellet also increasesignificantly as compared to control group (p=0.01. Average weight gain of fish fed pellet supplementedwith 10 g yeast/kg pellet was 15.00±1.00 g while control fish was 8.33 g. As conclusion, supplementationof baker’s yeast in feed could enhance nonspecific immune response and growth of Nile tilapia fish.

  17. Dietas peletizada e extrusada para machos revertidos de tilápias do Nilo (Oreochromis niloticus L., na fase de terminação Pelletized and extrused diets for reversed nile tilapia (Oreochromis niloticus L. males, in finishing phase

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    Wilson Massamitu Furuya

    1998-09-01

    Full Text Available O experimento foi conduzido com o objetivo de comparar dietas peletizada e extrusada para machos revertidos de tilápias do Nilo, de 188,9 a 362,4g. Foram utilizadas cem tilápias do Nilo, distribuídas em um delineamento inteiramente casualidade com dois tratamentos e cinco repetições. A cada cinco dias, registrou-se os dados de temperatura e transparência da água dos tanques. Com relação à conversão alimentar e taxa de sobrevivência, não houve diferença (P>0,05 entre as dietas peletizada e extrusada. O maior ganho de peso diário e taxa de eficiência proteica (PThis experiment was carried with the objective of comparing pelletized and extrused diets for reversed Nile tilapias, from 188.9 to 362.4g. One hundred Nile tilapias were, distributed in an entirely randomized design with two treatments and five replications. Temperature and water transparency data were taken every five days. Concerning feed conversion and survival rate there was no difference (P>0.05 between diets pelletized and extrused. The greatest gain and protein efficiency rate (P<0.05 were achieved by extrused diet, as well as the best result of uniformity. Regarding the average cost of ration per kilo gained by fish in each treatment, the least cost (P<0.05 was achieved by pelletized diet. It may be concluded that extrused diet favoured the great gain, however, the least cost of ration per kilo is achieved by pelletized diet.

  18. Growth and metabolic responses of whiteleg shrimp Litopenaeus vannamei and Nile tilapia Oreochromis niloticus in polyculture fed with potential probiotic microorganisms on different schedules: Crecimiento y respuesta metabólica del camarón blanco Litopenaeus vannamei y tilapia del Nilo Oreochromis niloticus en policultivo alimentado con microorganismos probióticos potenciales en diferentes frecuencias

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    Juan P Apún-Molina

    2015-07-01

    Full Text Available Probiotics and co-culture of shrimp and tilapia are two strategies to improve yield and eco-efficiency of both species. However, only few studies have analyzed the combination of these two strategies. This study analyzes the effect of a mixture of potential probiotics supplied in the diet at different frequencies in a system of shrimp (10 m-2 and tilapia (5 m-2 in a trial lasting 84 days. The probiotics mixture was composed of four lactic acid bacteria and one yeast strain that were supplied either daily, every 5 days, or every 10 days in the diet and compared with a control without any supply of probiotics. At the end of the experiment, blood chemistry and hematology of shrimp and tilapia were analyzed as an index of physiological condition. Water quality did not differ between treatments. The final weight, feed conversion ratio, and yield of shrimp were significantly higher with daily supply of probiotics compared to shrimp that did not receive probiotics supply, with intermediate values for treatments with probiotics supply every 5 or 10 days. However, level of supplementation every 5 days could be considered as optimal because no significant differences with daily supply were observed for any variable, whereas the supply each 10 days resulted in a significantly lower yield. Significantly higher final weight, feed conversion ratio, and yield of tilapia occurred with daily supplements. Blood cholesterol in tilapia significantly decreased with increasing frequency of probiotics supplementation. These results indicate that probiotics supplements for shrimp and tilapia cultivated simultaneously improved yields and physiological condition.

  19. Myo-inositol phosphate synthase expression in the European eel (Anguilla anguilla) and Nile tilapia (Oreochromis niloticus): effect of seawater acclimation.

    Science.gov (United States)

    Kalujnaia, Svetlana; Hazon, Neil; Cramb, Gordon

    2016-08-01

    A single MIPS gene (Isyna1/Ino1) exists in eel and tilapia genomes with a single myo-d-inositol 3-phosphate synthase (MIPS) transcript identified in all eel tissues, although two MIPS spliced variants [termed MIPS(s) and MIPS(l)] are found in all tilapia tissues. The larger tilapia transcript [MIPS(l)] results from the inclusion of the 87-nucleotide intron between exons 5 and 6 in the genomic sequence. In most tilapia tissues, the MIPS(s) transcript exhibits much higher abundance (generally >10-fold) with the exception of white skeletal muscle and oocytes, in which the MIPS(l) transcript predominates. SW acclimation resulted in large (6- to 32-fold) increases in mRNA expression for both MIPS(s) and MIPS(l) in all tilapia tissues tested, whereas in the eel, changes in expression were limited to a more modest 2.5-fold increase and only in the kidney. Western blots identified a number of species- and tissue-specific immunoreactive MIPS proteins ranging from 40 to 67 kDa molecular weight. SW acclimation failed to affect the abundance of any immunoreactive protein in any tissue tested from the eel. However, a major 67-kDa immunoreactive protein (presumed to be MIPS) found in tilapia tissues exhibited 11- and 54-fold increases in expression in gill and fin samples from SW-acclimated fish. Immunohistochemical investigations revealed specific immunoreactivity in the gill, fin, skin, and intestine taken from only SW-acclimated tilapia. Immunofluorescence indicated that MIPS was expressed within gill chondrocytes and epithelial cells of the primary filaments, basal epithelial cell layers of the skin and fin, the cytosol of columnar intestinal epithelial and mucous cells, as well as unknown entero-endocrine-like cells.

  20. Comprehensive identification and profiling of Nile tilapia (Oreochromis niloticus) microRNAs response to Streptococcus agalactiae infection through high-throughput sequencing.

    Science.gov (United States)

    Wang, Bei; Gan, Zhen; Cai, Shuanghu; Wang, Zhongliang; Yu, Dapeng; Lin, Ziwei; Lu, Yishan; Wu, Zaohe; Jian, Jichang

    2016-07-01

    MicroRNAs are a kind of small non-coding RNAs that participate in various biological processes. Deregulated microRNA expression is associated with several types of diseases. Tilapia (Oreochromis niloticus) is an important commercial fish species in China. To identify miRNAs and investigate immune-related miRNAs of O. niloticus, we applied high-throughput sequencing technology to identify and analyze miRNAs from tilapia infected with Streptococcus agalactiae at a timescale of 72 h divided into six different time points. The results showed that a total of 3009 tilapia miRNAs were identified, including in 1121 miRNAs which have homologues in the currently available databases and 1878 novel miRNAs. The expression levels of 218 tilapia miRNAs were significantly altered at 6 h-72 h post-bacterial infection (pi), and these miRNAs were therefore classified as differentially expressed tilapia miRNAs. For the 1121 differentially expressed tilapia miRNAs target 41961 genes. GO and KEGG enrichment analysis revealed that some target genes of tilapia miRNAs were grouped mainly into the categories of apoptotic process, signal pathway, and immune response. This is the first report of comprehensive identification of O. niloticus miRNAs being differentially regulated in spleen in normal conditions relating to S. agalactiae infection. This work provides an opportunity for further understanding of the molecular mechanisms of miRNA regulation in O. niloticus host-pathogen interactions.

  1. Conservação de filés de tilápia-do-nilo (Oreochromis niloticus em salga seca e salga úmida Nile tilapia (Oreochromis niloticus preservation by means of dry salting and saturated brine

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    F.S. Aiura

    2008-12-01

    Full Text Available Acompanhou-se o desenvolvimento dos processos da salga em salmoura saturada (salga úmida e salga seca de filés de tilápia-do-nilo (Oreochromis niloticus e avaliaram-se algumas características indicativas de qualidade do produto durante a estocagem. Os processos foram acompanhados por 156 horas na salga úmida e por 96 horas na salga seca, e os filés salgados foram estocados, respectivamente, por 60 e 45 dias à temperatura ambiente. Os teores máximos de cloreto nos filés (14% foram atingidos com 72 horas na salga úmida e com 36 horas na salga seca. Os filés de tilápia salgados em salmoura mantiveram as características próprias do produto por um período de 45 dias, e os submetidos à salga seca apresentaram baixo teor de umidade (6% e alta concentração de extrato etéreo (4,6%. Recomenda-se somente o processo de salga em salmoura saturada como forma de conservação dos filés de tilápia-do-nilo.The processes of salting of Nile tilapia fillets (Oreochromis niloticus submitted to saturated brine and dry salting were observed, and some characteristics that indicate the quality of the product during the storage were evaluated. The brine saturated process was followed up to 156 hours and the dry salting was followed up to 96 hours. When the salting finished, fillets were stored for 45 (dry salting and 60 days (saturated brine, respectively. The highest values for chloride in fillets (14% were reached within 72 hours in brine salting and 36 hours in dry salting. The tilapia fillets salted in brine kept the proper characteristics of the product for a period of 45 days and the fillets submitted to dry salting showed low moisture ratios (6% and a high concentration of lipids (4.6%. Thereby, it is only recommended the salting process in saturated brine to be used as a mean of conservation for Nile tilapia fillets.

  2. Broad Niche Overlap between Invasive Nile Tilapia Oreochromis niloticus and Indigenous Congenerics in Southern Africa: Should We be Concerned?

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    Tsungai A. Zengeya

    2015-07-01

    Full Text Available This study developed niche models for the native ranges of Oreochromis andersonii, O. mortimeri, and O. mossambicus, and assessed how much of their range is climatically suitable for the establishment of O. niloticus, and then reviewed the conservation implications for indigenous congenerics as a result of overlap with O. niloticus based on documented congeneric interactions. The predicted potential geographical range of O. niloticus reveals a broad climatic suitability over most of southern Africa and overlaps with all the endemic congenerics. This is of major conservation concern because six of the eight river systems predicted to be suitable for O. niloticus have already been invaded and now support established populations. Oreochromis niloticus has been implicated in reducing the abundance of indigenous species through competitive exclusion and hybridisation. Despite these well-documented adverse ecological effects, O. niloticus remains one of the most widely cultured and propagated fish species in aquaculture and stock enhancements in the southern Africa sub-region. Aquaculture is perceived as a means of protein security, poverty alleviation, and economic development and, as such, any future decisions on its introduction will be based on the trade-off between socio-economic benefits and potential adverse ecological effects.

  3. Effect of Nile tilapia (Oreochromis niloticus on the growth performance of Pacific white shrimp (Litopenaeus vannamei in a sequential polyculture system Efecto de la tilapia del Nilo (Oreochromis niloticus sobre el crecimiento del camarón blanco del Pacífico (Litopenaeus vannamei, en un sistema de policultivo secuencial

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    Cesar Hernández-Barraza

    2012-11-01

    Full Text Available The present study was carried out at the Environmental Research Laboratory (ERL, University of Arizona, to assess the effect of the addition of Nile tilapia (Oreochromis niloticus, at different densities, on the growth performance of Pacific white shrimp (Litopenaeus vannamei. The growth rate and feed conversion of shrimp, both in polyculture and monoculture, were evaluated. Shrimp-tilapia proportions were 20:8 individuals in Treatment One (T1, 20:4 individuals in Treatment Two (T2 and 20:2 individuals in Treatment Three (T3, while in Treatment Four (T4 shrimp were stocked as a control group with a ratio of 20:0. The experiment lasted for four weeks at 10 ppt water salinity. The shrimp and fish were fed once a day with 8% and 3% of their body weight, respectively, using a 35% protein feed. At the end of the experiment, the average individual weight and best feed conversion ratio were obtained in shrimp polyculture treatment with highest tilapia density 6.08 ± 0.18 g and 1.26 ± 0.01 respectively, while the lowest scores were found in the monoculture treatment with 5.14 ± 0.59 g and 1.35 ± 0.01, respectively (P El presente estudio se llevó a cabo en el Laboratorio de Investigación del Medio Ambiente (ERL. de la Universidad de Arizona, para evaluar el efecto de la adición de la tilapia del Nilo (Oreochromis niloticus a diferentes densidades, en el desempeno del crecimiento del camarón blanco del Pacífico (Litopenaeus vannamei. La tasa de crecimiento y conversión alimenticia del camarón, tanto en policultivo y monocultivo, fueron evaluados. Las proporciones de camarón y la tilapia fueron de 20:8 individuos en el tratamiento uno (T1, 20:4 en el tratamiento dos (T2 y de 20:2 en el tratamiento tres (T3, mientras que en el tratamiento cuatro (T4, únicamente fueron sembrados camarones, participando como grupo control con una relación de 20:0. El experimento se realizó durante cuatro semanas y agua a 10 ppm de salinidad. Los camarones y

  4. Successful production of Nile and blue tilapia fry - findings based on degree days and demonstrated for earthen ponds in subtropical climates

    Science.gov (United States)

    Degree-days can be used to adjust for seasonal variation in water temperature when planning tilapia fingerling production strategies and are calculated by subtracting a threshold temperature ("biological zero") from the mean daily water temperature; the threshold temperature is the temperature below...

  5. The Nile floodplain, hydroclimatic variability, and its relation with cultural dynamics in ancient Thebes (Luxor, Egypt)

    Science.gov (United States)

    Toonen, Willem H. J.; Graham, Angus; Pennington, Ben; Hunter, Morag; Strutt, Kris; Barker, Dominic; Masson, Aurelia; Emery, Virginia

    2016-04-01

    were contemporary. The abundance of ceramic material also allowed the reconstruction of sedimentation rates across the floodplain, which ranged between 0.8-2.2 mm/yr, largely in agreement with estimates from other studies. Importantly, there seems to have been a major decrease in sedimentation rates after the New Kingdom. Furthermore, the abandonment of the secondary channel of the Nile and the formation of a well-developed calcareous palaeosol (both of which could have been forced by drought and failing Nile floods) correlate with the demise of the New Kingdom. This suggests that regionally observed cultural and natural dynamics may have been driven by hydroclimatic variability in the larger Nile basin. A lower calcareous palaeosol, located at least 1m below the New Kingdom horizon, hints at a previous period of severe drought and its age is tentatively inferred as Old Kingdom. The age of this lower palaeosol needs to be confirmed by more precise dating, but could support the idea that cultural dynamics in ancient floodwater farming cultures are strongly linked to hydroclimatic change.

  6. Tilapia: environmental and nutritional requirements

    Science.gov (United States)

    Tilapia are an important species to global aquaculture production. Their adaptability to a wide range of environmental and nutritional conditions and their ability to grow and reproduce make them a prime species for aquaculture. Nonetheless, to achieve maximum performance in culture, tilapia requir...

  7. Preparo e caracterização de proteínas miofibrilares de tilápia-do-nilo para elaboração de biofilmes Extraction and properties of nile tilapia myofibrillar proteins for edible films

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    Ednelí Soraya Monterrey-Quintero

    2000-01-01

    Full Text Available A elaboração de filmes comestíveis à base de biopolímeros implica conhecimento das propriedades físico-químicas da macromolécula. Os objetivos deste trabalho foram a descrição de um método de preparo de proteínas miofibrilares de tilápia-do-nilo (Oreochromis niloticus, o estudo das propriedades relacionadas com a formação de filmes, e a caracterização dos biofilmes elaborados com a proteína. Músculo moído de tilápia-do-nilo, recém-abatida, foi lavado e processado até formação de uma pasta homogênea. A evolução das frações protéicas, durante o processamento, foi acompanhada por calorimetria diferencial de varredura. Estudou-se a solubilidade das proteínas miofibrilares liofilizadas (PML em função do pH (2-7. A identificação das frações protéicas e dos aminoácidos foi realizada por SDS-PAGE e cromatografia de troca iônica, respectivamente. Os biofilmes formados foram submetidos a testes de perfuração, de solubilidade e microscopia eletrônica. A amostra de PML, constituída apenas de proteínas miofibrilares, apresentou uma região de máxima solubilidade (96,9% em torno do pH 3,0 e elevado potencial de interações iônicas (74,4 kJ/100 kJ. Os biofilmes à base das PML de tilápia-do-nilo são pouco solúveis (abaixo de 20 g/100 g matéria seca. O glicerol influencia fortemente as propriedades mecânicas e a solubilidade dos biofilmes.The elaboration of edible films based on biopolymers, implies the knowledge of physicochemical properties of macromolecules. The objectives of this work were to describe a methodology of preparing Nile Tilapia myofibrillar proteins and study the properties related to formation and characterization of edible film elaborated with these proteins. Freshly slaughtered ground Nile Tilapia (Oreochromis niloticus muscle was washed and processed until the formation of a homogeneous paste. Evolution of protein fractions during processing was followed by scanning differential

  8. Colina e betaína em rações purificadas na nutrição da tilápia do Nilo (Oreochromis niloticus Choline and betaine in purified diets for Nile tilapia (Oreochromis niloticus

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    Ivan Vieira

    2001-12-01

    Full Text Available Problemas metabólicos observados em produções intensivas de tilápias do Nilo (Oreochromis niloticus têm sido relacionados à deficiência de colina nas rações. Com o objetivo de avaliar o efeito da suplementação dietética da colina na nutrição da espécie, rações purificadas contendo 0; 375; 750; 1.125; 1.500 ou 1.875 mg de cloreto de colina por kg, foram administradas ad libitum por 42 dias a tilápias do Nilo (5,09 ± 0,14 g, estocados em gaiolas de PVC atóxico (volume = 60 L, alojadas em caixas de polipropileno de 1000 L, em ambiente com condições controladas de temperatura e luminosidade, num delineamento experimental em blocos incompletos casualizados, com três parcelas por bloco (n=5. O ganho de peso (GDP e o índice de conversão alimentar (ICA de todos os tratamentos foram superiores ao controle. Não foram observadas diferenças para a quantidade de lipídios no fígado e tecido corporal, e sobrevivência (S%. Num segundo experimento, os peixes foram alimentados com rações suplementadas com 1.250 ou 2.500 mg de cloreto de colina por kg; ou 1.000; 2.000 ou 3.000 mg de betaína por kg. Não foram observadas diferenças significativas para S% e acúmulo de lipídeos hepáticos ou corporais; o ICA e GDP dos tratamentos suplementados com colina foram superiores aos dos tratamentos suplementados com betaína, mas não diferiram entre si. Níveis de suplementação superiores a 375 mg de cloreto de colina por kg de alimento melhoram o ICA e o GDP da tilápia do Nilo, mas a betaína não substitui efetivamente a colina em rações para a espécie.Metabolic problems detected in intensively raised Nile tilapia (Oreochromis niloticus are credited to possible sub-supplementation of coline in commercial feeds. To investigate the utilization of choline and betaine as feed supplement for the Nile tilapia, groups of 10 fingerlings (5.09 ± 0.14 g stocked in 30 PVC cages (60 L, kept under controlled environmental conditions inside

  9. Digestibilidade aparente de ingredientes do Semi-Árido Nordestino para tilápia do Nilo Apparent digestibility of ingredients of the Northeast Semi-Arid for Nile tilapia

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    Josivânia Rodrigues de Araújo

    2012-05-01

    Full Text Available O experimento avaliou o coeficiente de digestibilidade aparente (CDA da matéria seca (MS, energia bruta (EB, extrato etéreo (EE e proteína bruta (PB de ingredientes do Semi-Árido Nordestino: farinhas do feno de maniçoba (FM, do feno de leucena (FL e do feno da folha de mandioca (FFM, raspa de mandioca (RM e resíduos de vitivinícola (RV para tilápia do Nilo (Oreochromis niloticus. Os CDA para a MS, EB, EE e PB foram de 20,74%, 30,30%, 48,36% e 71,72% para FL; 19,34%, 17,08%, 30,03% e 44,88% para FM; 30,32%, 23,04%, 4,43% e 21,07% para FFM; 72,85%, 70,62%, 81,78% e 84,51% para RM e de 33,38%, 50,80%, 79,39% e 67,25% para RV. O feno de leucena, a raspa de mandioca e os resíduos de vitivinícola são promissores para a formulação de rações. A utilização dos ingredientes testados na composição de rações artesanais ou comercias para a tilápia do Nilo, bem como os níveis seguros para a inclusão destes devem ser testados.The experiment evaluated the apparent digestibility coefficient (CDA of dry matter (DM, gross energy (GE, ether extract (EE and crude protein (CP of regional alternative ingredients of Semi-arid Northeast as flour of maniçoba hay (FM, of Leucaena hay (FL and of cassava leaves (FFM, as well as cassava scrapings (RM and residues of wine (RV for Nile tilapia (Oreochromis niloticus. CDA for DM, GE, EE and CP were 20.74%, 30.30%, 48.36% and 71.72% for FL, 19.34%, 17.08%, 30.03% and 44.88% for FM, 30.32%, 23.04%, 4.43% and 21.07% for FFM, 72.85%, 70.62%, 81.78% and 84.51% for RM and 33.38%, 50.80%, 79.39% and 67.25% for RV. The leucaena hay, the cassava scrapings and residues of wine are promising for the formulation of diets for Nile tilapia. However, the use of tested ingredients in commercial and homemade diets to Nile tilapia, as well as the safe inclusion levels of these should be tested.

  10. Farinha de carne e ossos na alimentação de larvas de tilápia do Nilo Meat and bone meal to feed Nile tilapia larvae

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    Arcangelo Augusto Signor

    2010-04-01

    Full Text Available No presente trabalho, objetivou-se avaliar a inclusão de farinha de carne e ossos (FCO na alimentação de larvas de tilápia do Nilo. As dietas foram formuladas de forma a apresentarem-se isoproteicas (38,6% e isoenergéticas (3500kcal de ED kg-1, com diferentes níveis de inclusão (0; 5; 10 e 15% de FCO. Em um delineamento inteiramente casualizado, foram distribuídas 360 larvas de tilápia (6,59±0,02mg e 0,90±0,08cm em 24 aquários de 30L. Os peixes foram alimentados até a saciedade aparente às 8h, 10h30min, 13h, 15h30min e 18h, por 30 dias. Ao final do experimento, foram avaliados as médias de peso final (PF, o comprimento final (CF, o comprimento padrão (CP e a sobrevivência (SO, e os dados foram submetidos à análise de regressão pelo programa SAEG. O nível de inclusão de até 15% de FCO na dieta não influenciou o peso final das larvas. Entretanto, o maior CP foi observado nas larvas alimentadas com o maior nível de inclusão de FCO na dieta. Portanto, pode ser utilizado o total de até 15% de inclusão de FCO em rações para larvas de tilápia do Nilo.The present study evaluated the inclusion of meat and bone meal (FCO in Nile tilapia larvae feeding. The diet was formulated to be isoproteic (38.6% DP and isocaloric (3500kcal DE kg-1 with different FCO levels at 0; 5; 10 and 15%. A 30-day trial was carried out in a complete randomized design with 360 Nile tilapia larvae (6.59 ± 0.02mg and 0.90 ± 0.08cm distributed in 24 50l-aquaria and fed until satiation five times a day at 8h00, 10h30, 13h00, 15h30 and 18h00. At the end of the experiment the average final weight (PF, final length (CF, standard length (CP and survival (% (SO were evaluated and the data was submitted to a regression analyses. The Inclusion level of up to 15% of FCO in the diet did not influence larvae weight gain. However, the higher CP was observed in larvae fed with the highest level of FCO inclusion in diet. Therefore, it can be used a total of up to

  11. 尼罗罗非鱼仔鱼个体发育及性腺分化的发育%Ontogenetic Development and Gonadal Differentiation and Development of Larvae Nile Tilapia (Oreochromis niloticus L. )

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    陈兴汉; 刘晓春; 蒙子宁; 张勇; 林浩然; 叶卫

    2012-01-01

    通过形态学、组织学的描述和显微结构的观察,研究了尼罗罗非鱼(Oreochromis niloticus)仔鱼在自然水温条件下(26~30℃)的个体发育和性腺分化发育过程。结果表明,仔鱼个体发育分为2个时期,仔鱼前期(从出膜到卵黄囊消失)和仔鱼后期(卵黄囊消失至奇鳍褶消失);性腺发育分化的时序为:5DPH时,开始出现生殖嵴;10DPH时,出现少数原始生殖细胞,形成原始性腺;28DPH时,可清晰辨认卵原细胞,呈现明显的性腺分化组织学特征,至42DPH时可辨认精原细胞。%Larvae of Nile tilapia (Oreochromis niloticus) were observed morphologically, histologically and micro- structurally under the natural condition with the temperature ranging from 26℃ to 28℃ in terms of ontogenetic de- velopment and gonadal differentiation and development. Observations showed that the development of larvae Nile tilapia can be divided into two stages: early larval stage from hatching to the complete yolk-sac absorption, and late larval stage from the complete yolk-sac absorption to the appearance of odd fin fold. The sex differentiation oc- curs at around 28 days post hatching (DPH). The genital ridge, incomplete velum and enteron start to appear at 5 DPH. The primordial germ cells (PGCs) appear at 10 DPH although few, and form primordial gonad. The ooeytes can be easily distinguished at 28 DPH and show clear histological characteristics of gonadal differentiation. The spermatogonia can be distinguished at 42 DPH.

  12. A Comparison of the Beneficial Effects of Live and Heat-Inactivated Baker's Yeast on Nile Tilapia: Suggestions on the Role and Function of the Secretory Metabolites Released from the Yeast.

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    Chao Ran

    Full Text Available Yeast is frequently used as a probiotic in aquaculture with the potential to substitute for antibiotics. In this study, the involvement and extent to which the viability of yeast cells and thus the secretory metabolites released from the yeast contribute to effects of baker's yeast was investigated in Nile tilapia. No yeast, live yeast or heat-inactivated baker's yeast were added to basal diets high in fishmeal and low in soybean (diet A or low in fishmeal and high in soybean (diet B, which were fed to fish for 8 weeks. Growth, feed utilization, gut microvilli morphology, and expressions of hsp70 and inflammation-related cytokines in the intestine and head kidney were assessed. Intestinal microbiota was investigated using 16S rRNA gene pyrosequencing. Gut alkaline phosphatase (AKP activity was measured after challenging the fish with Aeromonas hydrophila. Results showed that live yeast significantly improved FBW and WG (P < 0.05, and tended to improve FCR (P = 0.06 of fish compared to the control (no yeast. No significant differences were observed between inactivated yeast and control. Live yeast improved gut microvilli length (P < 0.001 and density (P < 0.05 while inactivated yeast did not. The hsp70 expression level in both the intestine and head kidney of fish was significantly reduced by live yeast (P < 0.05 but not inactivated yeast. Live yeast but not inactivated yeast reduced intestinal expression of tnfα (P < 0.05, tgfβ (P < 0.05 under diet A and il1β (P = 0.08. Intestinal Lactococcus spp. numbers were enriched by both live and inactivated yeast. Lastly, both live and inactivated yeast reduced the gut AKP activity compared to the control (P < 0.001, indicating protection of the host against infection by A. hydrophila. In conclusion, secretory metabolites did not play major roles in the growth promotion and disease protection effects of yeast. Nevertheless, secretory metabolites were the major contributing factor towards improved gut

  13. Digestibilidade aparente da energia e nutrientes do farelo de canola pela tilápia do Nilo (Oreochromis niloticus Apparent nutrient and energy digestibility of canola meal for Nile tilapia (Oreochromis niloticus

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    Wilson Massamitu Furuya

    2001-06-01

    Full Text Available Este estudo foi realizado para determinar a energia digestível e a digestibilidade aparente de nutrientes do farelo de canola pela tilápia do Nilo (Oreochromis niloticus. O óxido de crômio (0,1% foi utilizado como indicador inerte em dieta semi-purificada, com coleta de fezes pelo sistema Guelph. Os peixes foram alimentados até saciedade aparente. O farelo de canola apresentou valores de energia e nutrientes digestíveis de: 77,84; 71,99; 86,92; 88,19; 67,16 e 29,86% para a matéria seca, energia, proteína, lipídios, cálcio e fósforo, respectivamente, correspondendo a 2969,98 (kcal/kg; 69,97; 32,6; 1,2; 0,41 e 0,28%, de energia digestível, matéria seca, proteína e lipídios digestíveis e cálcio e fósforo disponíveis, respectivamente. Os resultados obtidos neste trabalho evidenciam que a tilápia do Nilo pode utilizar eficientemente o farelo de canola.This study was carried out to determine the digestible energy and apparent nutrient digestibility of canola meal for Nile tilapia (Oreochromis niloticus. The chromic oxide (0.1% was used as an inert indicador in the semi-purified diet and faeces were collected by Guelph system. Fish were fed to apparent satiation. The apparent nutrient and energy digestibility of canola meal were: 77.84, 71.99, 86.92, 88.19, 67.16, and 29.86% for dry matter, energy, protein, lipids, calcium and phosphorus, respectively, corresponding to 2969,98 (kcal/kg; 69.97, 32.6, 1.2, 0.41, and 0.28% of, digestible energy, dry matter, protein and lipids and available calcium and phosphorus, respectively. The results obtained in this experiment evidence that Nile tilapia may be able to utilize canola meal eficiently.

  14. Body lipid deposition in Nile tilapia fed on rations containing tannin Deposição lipídica corporal em tilápia-do-nilo alimentada com rações com tanino

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    Felipe Shindy Aiura

    2007-01-01

    Full Text Available The aim of this work was to evaluate the effect of tannin sources and levels in rations, on the productive performance and body lipid deposition of Nile tilapias (Oreochromis niloticus during the finishing phase. Three hundred and forty-two fishes were distributed in 18 tanks. Rations were prepared using corn, sorghum varieties, with low and high tannin content, and tannic acid at 0.08, 0.34, and 0.60%. Weight gain, apparent feed conversion and protein efficiency rate were not influenced by the treatments. The highest body lipid deposition was observed for the tannic acid treatment (14.39%, while the diet containing sorghum with high tannin content yielded leaner body (12.01% than that of sorghum with low tannin content (13.31%. Diets containing sorghum provided lower levels of visceral fat. Rations with tannin contents did not harm the productive performance of Nile tilapia.O objetivo deste trabalho foi avaliar o efeito de fontes e níveis de tanino em rações para tilápia-do-nilo (Oreochromis niloticus, durante a engorda, sobre o desempenho produtivo e deposição lipídica corporal. Foram utilizados 342 peixes, distribuídos em 18 tanques. As rações foram preparadas com milho, variedades de sorgo com baixo e alto teor de tanino, e com ácido tânico a 0,08, 0,34, e 0,60%. Ganho de peso, conversão alimentar aparente e taxa de eficiência protéica não foram influenciados pelos tratamentos. A maior deposição lipídica corporal foi observada nas dietas com ácido tânico (14,39%; a dieta de sorgo com alto teor de tanino resultou em carcaças mais magras (12,01% do que as de sorgo com baixo teor de tanino (13,31%. Dietas com sorgo proporcionaram menores teores de gordura visceral. A presença de tanino nas rações não prejudicou o desempenho produtivo da tilápia-do-nilo.

  15. Desempenho da tilápia-do-Nilo arraçoada com dietas contendo farinha de sangue bovino atomizado ou convencional = Performance of nile tilapia fed with spray-dried or vat-dries bovine blood meal

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    Willian Vicente Narváez-Solarte

    2011-07-01

    Full Text Available Foi avaliado o desempenho e os índices de rendimento da tilápia-do-Nilo (Oreochromis niloticus alimentada com níveis crescentes de farinha de sangue atomizado (FSA ou de farinha de sangue convencional (FSC em dietas formuladas com base em aminoácidos digestíveis. Foram utilizados 252 alevinos, distribuídos num delineamento inteiramente casualizado, em esquema fatorial (2 x 4 + 1, duas classes de farinha de sangue com quatro níveis de inclusão de cada farinha na dieta, e uma dieta-controle, com quatro repetições. Os tratamentos consistiram em uma dieta-controle à base de farelo de soja, contendo 34% de proteína digestível (PD e 3.200 kcal de energia digestível kg-1 (ED, mais quatro rações formuladas com FSA e quatro rações com FSC, com inclusões de 5, 10, 15 e 20% de cada farinha na ração, mantendo-se os níveis de PD, ED, fósforo, cálcio, lisina, metionina, treonina e triptofano idênticos aos da dieta-controle. Concluiu-se que é possível utilizar até 15% da FSC em rações para tilápia-do-Nilo na fase de 5 a 150 g de peso vivo.The study evaluated the performance and carcass composition index of Nile tilapia (Oreochromis niloticus fed with diets containing increasing levels of spray-dried blood meal (SDBM and vat-dried blood meal (VDBM and formulated based on digestible amino acids. Two hundred and fifty-two fingerlings were distributed in a completelyrandomized design, in a (2 x 4 + 1 factorial model, two types of blood meal with four levels of each blood meal in the diet, and a control diet (without blood meal, with four replications. The treatments consisted of soybean meal-based control diet, with 34%digestible protein (DP and 3,200 kcal of digestible energy kg-1 (DE, plus four diets formulated with SDBM and four diets with VDBM, containing 5, 10, 15 and 20% of each meal in feed, maintaining identical DP, DE, phosphorus, calcium, lysine, methionine, threonine and tryptophan levels as those of the control diet. The

  16. Utilização de Saccharomyces cerevisiae como probiótico para tilápias-do-nilo durante o período de reversão sexual submetidas a um desafio sanitário Saccharomyces cerevisiae as probiotic for Nile Tilapia during the sexual reversion phase under a sanitary challenge

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    Fábio Meurer

    2006-10-01

    daily supply of 0.5 mL of fresh swine manure. Treatments consisted of a commercial diet for the sexual reversion of tilapia, with (TP or without (TT 0.1% of S. cerevisiae. The larvae were fed ad libitum five times a day. At the end of experiment, the fries were counted, measured and weighed. Two fries of each treatment were randomly chosen for gu removal and counting of the number of bacteria and total coliforms. No treatment effect on performance and survival was observed. Only the intestine of TP fries was colonized by SC. No significant differences were observed for bacteria and total coliforms per g of intestinal content and aquarium water. The use of Saccharomyces cerevisiae as probiotic in diets for Nile tilapia (Oreochromis niloticus during the sexual reversion period resulted in intestine settling with no effect on performance and survival, in a system of culture with sanitary challenge.

  17. A new and fast technique to generate offspring after germ cells transplantation in adult fish: the Nile tilapia (Oreochromis niloticus model.

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    Samyra M S N Lacerda

    Full Text Available BACKGROUND: Germ cell transplantation results in fertile recipients and is the only available approach to functionally investigate the spermatogonial stem cell biology in mammals and probably in other vertebrates. In the current study, we describe a novel non-surgical methodology for efficient spermatogonial transplantation into the testes of adult tilapia (O. niloticus, in which endogenous spermatogenesis had been depleted with the cytostatic drug busulfan. METHODOLOGY/PRINCIPAL FINDINGS: Using two different tilapia strains, the production of fertile spermatozoa with donor characteristics was demonstrated in adult recipient, which also sired progeny with the donor genotype. Also, after cryopreservation tilapia spermatogonial cells were able to differentiate to spermatozoa in the testes of recipient fishes. These findings indicate that injecting germ cells directly into adult testis facilitates and enable fast generation of donor spermatogenesis and offspring compared to previously described methods. CONCLUSION: Therefore, a new suitable methodology for biotechnological investigations in aquaculture was established, with a high potential to improve the production of commercially valuable fish, generate transgenic animals and preserve endangered fish species.

  18. Effects of feeding frequency on gastric evacuation, growth benefit and body composition of juvenile genetic improved farmed tilapia strain of Nile tilapia( Oreochromis niloticus)%投喂频率对尼罗系吉富罗非鱼幼鱼胃排空、生长性能和体组成的影响

    Institute of Scientific and Technical Information of China (English)

    孙晓锋; 冯健; 陈江虹; 罗波; 赵海祥; 赵华林

    2011-01-01

    A 6-week feeding experiment was conducted to determine the optimum feeding frequency for gastric evacuation, growth performance and body composition of the juvenile genetic improved farmed tilapia strain of Nile Tilapia( Oreochromis niloticus) (GIFT strain of Nile tilapia). At the start of the feeding trial, gastric evacuation rate of the fish was monitored after feeding to visual satiety. Gastric evacuation of the fish was best fitted with square root model. It was estimated that gastric feed contents gradually decreased and reached the pre-feeding level within 15 h and 80% evacuation would require 9 h, which suggested corresponded to the return of appetite. Six replicate groups of the 360 fish( initial weight 3. 72 g) were fed to visual satiety puffed feed at different feeding frequencies (four meals a day, three meals a day, two meals a day,four meals every 2 days,three meals every 2 days and two meals every 2 days). As feeding frequency decreased, the weight gain and feed efficiency of the juvenile gradually decreased. The specific growth ratios (SGR)of fish fed four meals a day,three meals a day and two meals a day were significantly higher than those of four meals every 2 days,three meals every 2 days and two meals every 2 days( P <0.05). The feed intakes of fish fed two meals a day, four meals every 2 days, three meals every 2 days and two meals every two days were significantly lower than those of three meals a day and four meals a day (P < 0. 05). As feeding frequency decreased, moisture contents of fish body increased and the contents of fat and protein decreased gradually,and there were significant difference between the fish fed four meals a day,three meals a day and the fish fed two meals every 2 days. Hepatosomatic indices of fish were not significantly different between all test groups. It is concluded that two meals a day is more effective than other feeding frequencies for improving growth performance or feed efficiency of juvenile GIFT strain of

  19. 吉富罗非鱼家系构建及抗病力检测%Family establishment and disease resistance of different families of GIFT Nile tilapia Oreochromis niloticus

    Institute of Scientific and Technical Information of China (English)

    朱佳杰; 李莉萍; 唐瞻杨; 周宇; 罗永巨; 甘西

    2012-01-01

    文章以吉富罗非鱼(GIFT strain Oreochromis niloticus)为研究对象,按照1雄配1雌原则进行家系配对,待家系鱼生长至50~60 g·尾-1时人工感染无乳链球菌(Streptococcus agalactiae)(菌株GD001).通过对GD001菌株半数致死浓度测定及各家系感染死亡率的统计,研究了GD001无乳链球菌感染对各家系吉富罗非鱼抗病力的影响.结果表明,1)配对成功家系67个,经繁殖性能筛选后留种53个,家系留种率为79.1%;2)GD001菌株的半数致死浓度为4×108cfu·mL-1,感染后2~6d为死亡高峰期;3)GD001菌感染53个家系后有11个家系的成活率在90%以上,15个家系的成活率在70%~89%,19个家系的成活率在30%~69%,8个家系的成活率低于30%,表明不同家系对GD001菌株的抗病力存在着显著的差异(P<0.05).%The families of GIFT strain Nile tilapia ( Oreochromis niloticus ) were established by pair-mating and the juveniles (50 ~ 60 g) in each family were challenged by Streptococcus agalactiae (GD001 strain). According to the median lethal concentration ( LC50) and infection mortality rate of each family, we evaluated the disease resistance of GIFT strain Nile tilapia to the challenge of S. Agalactiae GD001 strain. The results show that; 1) 67 full-sibling families were successfully established, and 53 families (79. 1% ) were maintained based on their reproductive performance; 2) The LC50 of S. Agalactiae GD001 strain to tilapia was 4×108cfu·mL-1; 3) Among the 53 families, 11 families had survival rate of over 90% , 15 families (70%~89% ) , 19 families (30% ~69% ) and 8 families (less than 30% ). It is suggested that the disease resistances of different GIFT families challenged with S. Agalactiae were significantly different (P < 0. 05).

  20. Safety and immunogenicity of an oral DNA vaccine encoding Sip of Streptococcus agalactiae from Nile tilapia Oreochromis niloticus delivered by live attenuated Salmonella typhimurium.

    Science.gov (United States)

    Huang, L Y; Wang, K Y; Xiao, D; Chen, D F; Geng, Y; Wang, J; He, Y; Wang, E L; Huang, J L; Xiao, G Y

    2014-05-01

    Attenuated Salmonella typhimurium SL7207 was used as a carrier for a reconstructed DNA vaccine against Streptococcus agalactiae. A 1.02 kb DNA fragment, encoding for a portion of the surface immunogenic protein (Sip) of S. agalactiae was inserted into pVAX1. The recombinant plasmid pVAX1-sip was transfected in EPC cells to detect the transient expression by an indirect immunofluorescence assay, together with Western blot analysis. The pVAX1-sip was transformed by electroporation into SL7207. The stability of pVAX1-sip into Salmonella was over 90% after 50 generations with antibiotic selection in vitro while remained stable over 80% during 35 generations under antibiotic-free conditions. The LD50 of SL/pVAX1-sip was 1.7 × 10(11) CFU/fish by intragastric administration which indicated a quite low virulence. Tilapias were inoculated orally at 10(8) CFU/fish, the recombinant bacteria were found present in intestinal tract, spleens and livers and eventually eliminated from the tissues 4 weeks after immunization. Fish immunized at 10(7), 10(8) and 10(9) CFU/fish with different immunization times caused various levels of serum antibody and an effective protection against lethal challenge with the wild-type strain S. agalactiae. Integration studies showed that the pVAX1-sip did not integrate with tilapia chromosomes. The DNA vaccine SL/pVAX1-sip was proved to be safe and effective in protecting tilapias against S. agalactiae infection.

  1. Influences of dietary biotin and avidin on growth, survival, deficiency syndrome and hepatic gene expression of juvenile Nile tilapia Oreochromis niloticus.

    Science.gov (United States)

    Sarker, Pallab Kumer; Yossa, Rodrigue; Karanth, Santhosh; Ekker, Marc; Vandenberg, Grant W

    2012-08-01

    This study was undertaken to assess the interactive effects of dietary biotin and avidin on growth, feed conversion, survival and deficiency syndrome of tilapia and to determine the influence of dietary biotin deficiency on the expression of key genes related to biotin metabolism in tilapia. Six iso-nitrogenous and iso-energetic diets based on a common purified basal diet (vitamin-free casein as the protein source) were prepared for this study. The six dietary groups were 0 g avidin with 0 mg biotin (A0B0), 0 g avidin with 0.06 mg biotin/kg diet (A0B1), four avidin-supplemented diets incorporating at a incremental concentrations 0.25, 0.5, 1.0 and 2.0 g/kg diet with 0.06 mg biotin/kg diet (A15B1, A30B1, A60B1 and A120B1). Fish were hand-fed three times a day to apparent satiation for 12 weeks. Each diet was fed to three replicate groups of fish. Fish were kept in glass aquaria in a recirculating aquaculture system under standardized environmental conditions. Growth was significantly higher in fish that received the biotin-supplemented diet (A0B1), compared to diets lacking biotin or supplemented with avidin. Tilapia fed higher concentration of avidin-supplemented diets (A60B1 and A120B1) showed significant growth depression and displayed severe deficiency syndromes such as lethargy, anorexia, circular swimming and convulsions, which ultimately lead to death. There was a strong proportional linear relationship between the avidin content of the diet and feed conversion ratio, FCR (y = 0.43x + 0.135; r = 0.960; P protein efficiency ratio, PER (y = -0.309x + 2.195; r = 0.961; P levels of biotinidase, pyruvate carboxylase, propionyl-CoA carboxylase-A and propionyl-CoA carboxylase-B transcripts were noted in fish fed all graded level of avidin-supplemented diets. A broken-line analysis indicated that feeding tilapia a diet with 44.5 times more avidin than the dietary biotin requirement can induce deficiency syndromes including retarded growth, when

  2. Agonistic and reproductive behaviors in males of red hybrid tilapia, Oreochromis niloticus (Linnaeus, 1758 x O. mossambicus (Peters, 1852 (Osteichthyes: Cichlidae

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    APT Medeiros

    Full Text Available The red hybrid tilapia, Oreochromis niloticus (Linnaeus, 1758 x O. mossambicus (Peters, 1852 is a fertile hybrid used in the semi-intensive level of fish culture in the Northeast of Brazil. It is a territorial cichlid and is highly aggressive towards conspecifics during the breeding season. The purpose of this study was to investigate and describe the aggressive behaviour displayed by the males of this hybrid in non-reproductive and reproductive contexts. Behavioural observations revealed that aggression displayed by the reproductive males of red hybrid tilapia included threatening, undulation, parallel, lateral and frontal attacks, chasing, escape and submission. Possession of a territory influenced male aggressiveness, which was more intense in their own territory than that observed in a neutral situation. The males built nests, irrespective of female presence. All the behavioural patterns were in accordance with those previously described for one parental species, the Nile tilapia, O. niloticus.

  3. Milheto em rações para a tilápia do Nilo (Oreochromis niloticus durante a reversão sexual - DOI: 10.4025/actascianimsci.v26i3.1796 Pearl millet in diets to Nile tilapia (Oreochromis niloticus during sex reversion - DOI: 10.4025/actascianimsci.v26i3.1796

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    Carmino Hayashi

    2004-04-01

    Full Text Available Objetivou-se testar a inclusão de milheto em rações para a tilápia do Nilo durante a fase de reversão sexual, sobre os parâmetros finais de peso, comprimento, sobrevivência e eficiência da reversão sexual. Foram utilizadas 1.200 larvas de tilápia do Nilo, distribuídas em 24 tanques-rede, em um delineamento em blocos inteiramente casualizados composto por seis tratamentos e quatro repetições. As seis diferentes rações experimentais foram formuladas, com níveis crescentes de inclusão de milheto (0%, 2%, 4%, 6%, 8% e 10%, sendo estas com 38,6% de proteína digestível e 3.800 kcal/kg de energia digestível. O peso final médio das tilápias apresentou um aumento linear (p 0,05. O milheto pode ser incluído em até 10% na ração da tilápia do Nilo durante o período de reversão sexual.The present study aimed to evaluate pearl millet inclusion in diets of Nile tilapia during sex reversion, on final parameters of weight, length, survival, and effectiveness of sex reversion. One thousand and two hundred Nile tilapia larvae were distributed in twenty four hapas, which were installed in four 1,000L tanks. The experimental design was in completely randomized blocks with six treatments and four replicates. Six different experimental diets were formulated with different levels of pearl millet (0, 2, 4, 6, 8, and 10%, contain 38.6% of digestible protein and 3,800 kcal/kg of digestible energy. The final weight of Nile tilapia showed a linear (P>0.01 growth proportional to pearl millet increase, but none of the others showed significant difference (P<0.05 between treatments. The pearl millet can be included up to 10% of Nile tilapia diet during sex reversion.

  4. Comparative proteome analysis of two Streptococcus agalactiae strains from cultured tilapia with different virulence.

    Science.gov (United States)

    Li, Wei; Su, You-Lu; Mai, Yong-Zhan; Li, Yan-Wei; Mo, Ze-Quan; Li, An-Xing

    2014-05-14

    Streptococcus agalactiae is a major piscine pathogen, which causes significant morbidity and mortality among numerous fish species, and results in huge economic losses to aquaculture. Many S. agalactiae strains showing different virulence characteristics have been isolated from infected tilapia in different geographical regions throughout South China in the recent years, including natural attenuated S. agalactiae strain TFJ0901 and virulent S. agalactiae strain THN0901. In the present study, survival of tilapia challenged with S. agalactiae strain TFJ0901 and THN0901 (10(7)CFU/fish) were 93.3% and 13.3%, respectively. Moreover, there are severe lesions of the examined tissues in tilapia infected with strain THN0901, but no significant histopathological changes were observed in tilapia infected with the strain TFJ0901. In order to elucidate the factors responsible for the invasive potential of S. agalactiae between two strains TFJ0901 and THN0901, a comparative proteome analysis was applied to identify the different protein expression profiles between the two strains. 506 and 508 cellular protein spots of S. agalactiae TFJ0901 and THN0901 were separated by two dimensional electrophoresis, respectively. And 34 strain-specific spots, corresponding to 27 proteins, were identified successfully by MALDI-TOF mass spectrometry. Among them, 23 proteins presented exclusively in S. agalactiae TFJ0901 or THN0901, and the other 4 proteins presented in different isomeric forms between TFJ0901 and THN0901. Most of the strain-specific proteins were just involved in metabolic pathways, while 7 of them were presumed to be responsible for the virulence differences of S. agalactiae strain TFJ0901 and THN0901, including molecular chaperone DnaJ, dihydrolipoamide dehydrogenase, thioredoxin, manganese-dependent inorganic pyrophosphatase, elongation factor Tu, bleomycin resistance protein and cell division protein DivIVA. These virulence-associated proteins may contribute to identify new

  5. Farinha de resíduos da filetagem de tilápias na alimentação de tilápia-do-nilo (Oreochromis niloticus na fase de reversão sexual Effects of feeding tilapia filleting by-product meal for nile tilapia (Oreochromis niloticus L. during the sexual reversion phase

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    Wilson Rogério Boscolo

    2005-12-01

    Full Text Available Este trabalho foi realizado com o objetivo de avaliar a inclusão da farinha de resíduos da indústria de filetagem de tilápias (FT na alimentação da tilápia-do-nilo na fase de reversão sexual. Foram utilizadas 375 larvas com dois a três dias de idade, distribuídas em 25 aquários com capacidade para 30 L, em delineamento inteiramente casualisado, com cinco tratamentos e cinco repetições, sendo a unidade experimental constituída por um aquário com 15 larvas. Foram elaboradas cinco rações isoprotéicas e isoenergéticas com 38,6% de proteína digestível e 3.800 kcal de ED/kg, com níveis de 0, 5, 10, 15 e 20% de inclusão de FT. Os valores de temperatura, oxigênio dissolvido, pH e condutividade elétrica da água dos aquários durante o período experimental foram de 24,53 ± 1,60ºC; 4,81 ± 0,68 mg/L; 7,70 ± 0,25; e 175,97 ± 108,46 µS/cm, respectivamente. Ao final do experimento, não foram observadas diferenças no peso e comprimento final, no fator de condição, na sobrevivência e no índice de reversão sexual das larvas alimentadas com a FT. A inclusão de até 20% de FT em rações para tilápia do Nilo na fase de reversão sexual não causa prejuízo ao desempenho dos peixes.The effects of feeling tilapia filleting by-product meal (TF for Nile tilapia (Oreochromis Niloticus L. during the sexual reversion phase were evaluated. Three hundred and seventy-five 2-3-d larvaes were allotted to 25 30L-aquariums, according to a complete randomized design with five treatments of five replications. Aquarium with 15 larvae comprised the experimental unit. Diets were formulated to be isonitrogenous and isoenergetic and contained 38.6% of digestible protein and 3,800 kcal of ED/kg, on increasing levels of TF (0, 5, 10, 15, and 20%. Mean temperature, dissolved oxygen, pH and electrical conductivity rates of water during the experimental period were of 24.53 ± 1.60ºC; 4.81 ± 0.68 mg/L; 7.70 ± 0.25; and 175.97 ± 108.46 µ

  6. O extrato de maracujá sobre a morfometria de hepatócitos da tilápia do Nilo The passion fruit on hepatocytes morphometry of Nile tilapia

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    Ricardo Henrique Franco de Oliveira

    2010-12-01

    Full Text Available Avaliaram-se os efeitos do extrato de maracujá veiculado na dieta (0, 50, 100 e 200mg kg-1 sobre o consumo de alimento, o ganho em peso e os níveis de glicose e cortisol plasmático de juvenis de tilápias do Nilo (87,0±6,6g. Ao final do experimento (28 dias, os peixes foram eutanasiados para remoção do fígado, visando à avaliação da área citoplasmática, contagem de células e verificação dos estoques de glicogênio hepático. Os dados foram submetidos à ANOVA unidirecional, comparando-se as médias pelo Teste de Tukey (PThe effects of passion fruit extract (0, 50, 100 and 200mg kg-1 on food consumption, growth and glucose levels and plasma cortisol were investigated in juvenile Nile tilapia (87.0±6.6g. After 28 days, fish were killed and the liver was removed for study of cytoplasm area, cell count and verification of hepatic glycogen stores. The data were subjected to one-way ANOVA comparing the means by Tukey´s test (P<0.05, with further study to establish the regression curves of cytoplasm areas related to different doses of the extract. The inclusion of the extract in the diet did not affect food consumption and growth, and all fish showed increased glucose and reduced plasma cortisol, without differences between treatments. The cytoplasm area increased quadratically as the doses increased, mainly for 100mg kg-1, resulting in an inverted "U" dose-response curve. The increase of cytoplasm area resulted from hepatic glycogen storage, as confirmed by salivary amylase. It was concluded that passion fruit extract can be delivered in the diet of juvenile tilapia, without impairing of food consumption and growth, and that the product affects the hepatocytes morphometry, suggesting flavonoids activity on carbohydrate metabolism.

  7. A thiopurine drug inhibits West Nile virus production in cell culture, but not in mice.

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    Pei-Yin Lim

    Full Text Available Many viruses within the Flavivirus genus cause significant disease in humans; however, effective antivirals against these viruses are not currently available. We have previously shown that a thiopurine drug, 6-methylmercaptopurine riboside (6MMPr, inhibits replication of distantly related viruses within the Flaviviridae family in cell culture, including bovine viral diarrhea virus and hepatitis C virus replicon. Here we further examined the potential antiviral effect of 6MMPr on several diverse flaviviruses. In cell culture, 6MMPr inhibited virus production of yellow fever virus, dengue virus-2 (DENV-2 and West Nile virus (WNV in a dose-dependent manner, and DENV-2 was significantly more sensitive to 6MMPr treatment than WNV. We then explored the use of 6MMPr as an antiviral against WNV in an immunocompetent mouse model. Once a day treatment of mice with 0.5 mg 6MMPr was just below the toxic dose in our mouse model, and this dose was used in subsequent studies. Mice were treated with 6MMPr immediately after subcutaneous inoculation with WNV for eight consecutive days. Treatment with 6MMPr exacerbated weight loss in WNV-inoculated mice and did not significantly affect mortality. We hypothesized that 6MMPr has low bioavailability in the central nervous system (CNS and examined the effect of pre-treatment with 6MMPr on viral loads in the periphery and CNS. Pre-treatment with 6MMPr had no significant effect on viremia or viral titers in the periphery, but resulted in significantly higher viral loads in the brain, suggesting that the effect of 6MMPr is tissue-dependent. In conclusion, despite being a potent inhibitor of flaviviruses in cell culture, 6MMPr was not effective against West Nile disease in mice; however, further studies are warranted to reduce the toxicity and/or improve the bioavailability of this potential antiviral drug.

  8. Níveis de farinha de peixe em rações para juvenis de tilápia Levels of fish meal in diets for Nile tilapia juveniles

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    Edvânia da Conceição Pontes

    2010-08-01

    Full Text Available Avaliou-se a influência do uso na ração de farinha de peixe suplementada com aminoácidos sobre o desempenho, as características de carcaça e a análise hematológica de juvenis de tilápia-do-nilo. Utilizaram-se 140 juvenis com peso médio de 14,0 ± 0,14 g, distribuídos aleatoriamente em delineamento inteiramente casualizado, com cinco níveis de farinha de peixe (0; 1,5; 3,0; 4,5 e 6,0% na ração, cada um com quatro repetições. As rações foram isoenergéticas (3.000 kcal de energia digestível e isocálcicas, e os peixes foram alimentados três vezes ao dia, até saciedade aparente, durante 60 dias. Foram avaliados o ganho de peso, o consumo de ração, a conversão alimentar aparente, a taxa de eficiência protéica, o índice hepatossomático, o peso da carcaça, o rendimento de carcaça, a retenção de nitrogênio e as taxas de hematócrito e hemoglobina. Os níveis de farinha de peixe não influenciaram o ganho de peso, a conversão alimentar, o consumo de ração, o índice hepatossomático, o rendimento de carcaça, o peso da carcaça e a taxa de hemoglobina, mas tiveram efeito quadrático sobre a retenção de nitrogênio, o teor de umidade e de gordura na carcaça e a taxa de hematócrito. Quanto maiores os níveis de farinha de peixe, menor a taxa de eficiência proteica e mais altos os teores de proteína e cinzas na carcaça. O nível de 3% de farinha de peixe não afeta o desempenho nem as características de carcaça de juvenis de tilápia-do-nilo.This study was conducted to evaluate, in the ration, the use of fish meal supplement with amino acids on performance, carcass characteristics, and on hematological analysis in Nile tilapia juvenils. It was used 140 juveniles with an average weight of 14.0 ± 0.14 g, randomly distributed in a complete random design with five levels of fish meal (0; 1.5; 3.0; 4.5; and 6.0% in the ration, each one with four replicates. The rations were isoenergetic (3,000 kcal of digestible

  9. Mesquite bean and cassava leaf in diets for Nile tilapia in growth=Farelos da vagem da algaroba e da folha da mandioca em rações para tilápia do Nilo em crescimento

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    Leandro Batista Costa

    2012-07-01

    Full Text Available This work evaluated the inclusion of mesquite bean bran (Prosopis juliflora and cassava leaf bran (Manihot esculenta in diets for Nile tilapia (85.22 ± 3.13 g. Three hundred and thirty-six fish were distributed in 28 fiberglass tanks (120 L in a 2 × 4 factorial scheme for two sources of oil and four levels of bran (0, 5, 10 and 20% (n = 4. After 60 days, growth performance (feed intake, weight gain, apparent feed conversion and survival rate and fish body composition were evaluated. Heights and density of villi were measured for morphometric analysis of the intestinal mucosa. Animal performance, body composition and villi density were not affected (p > 0.05 by the source and level of inclusion of bran. There was a significant effect of the level of inclusion of bran on villi height, with a linear trend, indicating that the higher the inclusion levels of bran, the lower the height of the villi. The bran studied can be used in diets for Nile tilapia up to 20% without compromising growth performance and body composition change, but the presence of these by-products can result in a deleterious effect on fish villi.Avaliou-se a inclusão dos farelos da vagem da algaroba (Prosopis juliflora e folha da mandioca (Manihot esculenta em rações para tilápia do Nilo (85,22 ± 3,13 g. Foram utilizados 336 peixes, distribuídos em 28 tanques (120 L, em esquema fatorial 2 x 4, duas fontes de óleo e quatro níveis de farelo (0, 5, 10 e 20% (n = 4. Ao final de 60 dias, foram avaliados o desempenho zootécnico (consumo de ração, ganho de peso, conversão alimentar aparente e taxa de sobrevivência e a composição da carcaça dos peixes. Para análise da histologia intestinal, foram mensuradas a altura e a densidade das vilosidades. O desempenho zootécnico, a composição da carcaça e a densidade das vilosidades intestinais não foram afetados (p > 0,05 pela fonte e nível de inclusão de farelo. Houve efeito significativo do nível de inclusão dos

  10. True and apparent digestibility of protein and amino acids of feed in Nile tilapia Digestibilidade aparente e verdadeira de proteína e aminoácidos de alimentos em tilápia-do-nilo

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    Felipe Barbosa Ribeiro

    2011-05-01

    Full Text Available It was determined in this work the coefficients of apparent and true digestibility of protein and amino acids of five feeds (corn, wheat bran, soybean meal, corn gluten meal, fish meal in Nile tilapia. It was used 252 reverted Thai strain Nile tilapia (Oreochromis niloticus in growth phase, with weight of 310 ± 9.68 g, distributed in experimental randomized blocks design, with five treatments, six replicates per treatment and seven fish per experimental unit. Each experimental diet contained a single source of protein, composed by the studied ingredients. An additional group of fish was fed protein-free diet for quantification of the endogenous fraction and determination of true digestibility coefficients. Digestibility was estimated by the indirect method by using chromium oxide at the concentration of 0.50% of the diet as a marker, performing fecal collection at every four hour interval by using decantation technique. Coefficients of apparent digestibility of the protein and amino acids are: corn, 83.57 and 82.45%; wheat bran 82.87 and 81.47%; soybean meal 91.12 and 89.41%; corn gluten meal 90.07 and 87.78%; fish meal 83.53 and 81.65% respectively. Coefficients of true digestibility of protein and the mean of the amino acids are: corn, 90.02 and 89.60%; wheat bran 89.62 and 89.14%; soybean meal 93.58 and 91.88%; corn gluten meal 92.50 and 90.34%; fish meal 86.01 and 84.27%, respectively.Foram determinados nesta pesquisa os coeficientes de digestibilidade aparente e verdadeira da proteína e dos aminoácidos de cinco alimentos (milho, farelo de trigo, farelo de soja, glúten de milho e farinha de peixe em tilápias-do-nilo. Utilizaram-se 252 tilápias revertidas (Oreochromis niloticus em fase de crescimento, da linhagem tailandesa, com peso de 310 ± 9,68 g, distribuídas em delineamento de blocos casualizados, composto de cinco tratamentos, seis repetições por tratamento e sete peixes por unidade experimental. Cada dieta experimental

  11. Energia digestível para larvas de tilápia-do-nilo (Oreochromis niloticus na fase de reversão sexual Digestible energy for nile tilapia (Oreochromis niloticus larvae in the sexual reversion phase

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    Wilson Rogério Boscolo

    2005-12-01

    Full Text Available Este trabalho foi realizado com o objetivo de se avaliar o efeito de diferentes níveis de energia digestível na ração sobre o desempenho de larvas de tilápia-do-nilo (Oreochromis niloticus, durante a fase de reversão sexual. Foram utilizadas 375 larvas com peso e comprimento inicial de 21,0 ± 4,0 mg e 11,9 ± 7,2 mm, respectivamente, distribuídos em 25 aquários com capacidade de 30 L, em um delineamento experimental inteiramente casualizado, composto por cinco tratamentos e cinco repetições, em que a unidade experimental foi considerada como um aquário contendo 15 larvas. As rações foram formuladas de modo a conterem 3.300; 3.525; 3.750; 3.975 e 4.200 kcal/kg de energia digestível e serem isoprotéicas (38,6% de proteína digestível. Os animais foram alimentados ad libitum cinco vezes ao dia. Ao final do experimento, foram analisadas as médias de peso final (PF, sobrevivência (SO, fator de condição (FC e comprimento final (CF. O aumento de ED nas rações proporcionou redução linear no PF e CF dos peixes. Não foram observadas diferenças na SO e FC dos peixes nos diferentes tratamentos. Conclui-se que o aumento nos níveis de energia digestível em rações para larvas de tilápia-do-nilo durante a reversão sexual proporciona redução no desempenho.This experiment was conducted to evaluate different levels of digestible energy on the performance of Nile tilapia larvae (Oreochromis niloticus during the sexual reversion phase. Three hundred and seventy-five larvae with initial average length and weight of 21.0±4.0 mg and 1.19±0.72 cm, respectively, were allotted to 25 30L-aquarium. A completely randomized design with five treatments and five replicates was used. The aquarium with 15 larvae was the experimental unit. The diets were formulated to contain levels of 3,300, 3,525, 3,750, 3,975, and 4,200 kcal/kg of digestible energy and to be isoprotein (38.6% digestible protein. The animals were fed ad libitum five times a

  12. Yeast as probiotic for Nile tilapia during the sexual reversion phase Levedura como probiótico na reversão sexual da tilápia do Nilo

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    Leda Maria Saragiotto Colpini

    2008-12-01

    Full Text Available The effect of including Saccharomyces cerevisiae (SC as probiotic in rations for Nile tilapia during sexual reversion on performance, percentage of sexual reversion and intestine settling, under sanitary challenge, was evaluated. The treatments consisted of a commercial ration for sexual reversion with 0.1% of SC (1010 SC Colony Formation Unit per g of product (TP or without the probiotic (TT. One fingerling was randomly chosen for intestine removal and counting of the number of bacteria and another ten fingerlings were analyzed for the effectiveness of sexual reversion (ERS. Performance, survival rate, ERS, and hepatic-somatic index were not affected (P>0.05 by dietary SC. The Saccharomyces cerevisiae settling in the intestine was noticed only in fingerlings fed TP. The main isolated bacteria were Bacillus spp. and Enterococcus spp., and no negative gram bacteria were observed. Live yeast can be used as probiotic in meal rations for Nile tilapia, during the sexual reversion, with no effect on performance and se sexual reversion process and due to the intestine settling and microbiota change.Objetivou-se avaliar a influência da inclusão da Saccharomyces cerevisiae (SC como probiótico em rações para a tilápia do Nilo (Oreochromis niloticus no período de reversão sexual sobre o desempenho, a porcentagem de reversão sexual e a colonização intestinal, em um ambiente de baixo desafio sanitário. Foram utilizadas 200 larvas de 2 dias de idade, distribuídas em um delineamento completamente casualizado com dois tratamentos e quatro repetições. Os tratamentos consistiram de uma ração comercial para reversão sexual de tilápia contendo 0,1% de SC (1010 Unidades Formadoras de Colônia de SC por g de produto (TP e outra o sem o probiótico (TT. O intestino de um alevino de cada unidade experimental foi retirado assepticamente e o seu conteúdo foi submetido à contagem e identificação dos gêneros bacterianos presentes e outros dez

  13. Fitase líquida em dieta extrusada para juvenis de tilápia do Nilo (Oreochromis niloticus = Liquid phytase in extruded diet for juvenile Nile tilapia (Oreochromis niloticus

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    Tarcila Souza de Castro Silva

    2007-10-01

    Full Text Available Este trabalho foi realizado para avaliar a utilização de fitase líquida sobre o desempenho de juvenis de tilápia do Nilo. Foram utilizados 176 peixes com peso inicial de 45,84 ± 3,31 g, alimentados com dietas sem e com 250; 500 e 1.000 unidades de fitase (UF kg-1 da dieta, durante 62 dias. Foi utilizada dieta-controle com 3012 kcal de energia kg-1, 29% de proteína bruta e 0,23% de fósforo disponível. Os peixes foram distribuídos em delineamento de blocos ao acaso, com quatro tratamentos e quatro repetições. Não foi observado efeito dos níveis de inclusão de fitase sobre o consumo, índice hepatossomático,gordura visceral, sobrevivência, retenção de cálcio nos ossos e teores de umidade, proteína bruta e cinzas na carcaça. Foi observado efeito linear crescente dos níveis de fitase sobre a retenção de fósforo e sobre os coeficientes de digestibilidade aparente da proteína bruta e do fósforo das dietas. Foi observado efeito quadrático dos níveis de suplementação de fitase sobre o ganho de peso, conversão alimentar, taxa de eficiência protéica, rendimento decarcaça e gordura na carcaça, em que foram estimados os valores de 350; 500; 500; 516 e 647 UF kg-1 de dieta para melhor valor destas variáveis, respectivamente. Conclui-se que a utilização 500 UF kg-1 é adequada em dietas para juvenis de tilápia do Nilo.This study was undertaken to evaluate the effects of liquid phytase on the performance of juvenile Nile tilapia. It was used 176 fish (45.84 ± 3.31 g. The fish were fed diets without phytase and with 250; 500 and 1,000 phytase units (PU kg-1 of diet, during62 days. A control diet was used containing 3,012 kcal digestible energy kg-1, 29% crude protein and 0.23% available phosphorus. The fish were assigned to a randomized block design, with four treatments and four replications. No effect was observed on the levels ofdietary phytase on feed intake, hepatosomatic index, visceral fat, survival, as well as on

  14. Exigência de fósforo disponível para tilápia-do-nilo (35 a 100 g Available phosphorus requirement of Nile tilapia (35 to 100 g

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    Wilson Massamitu Furuya

    2008-06-01

    Full Text Available Objetivou-se determinar a exigência de fósforo disponível para tilápias-do-nilo. Utilizaram-se 144 peixes com peso vivo inicial de 35,33 ± 0,66 g, distribuídos em delineamento de blocos ao acaso, com quatro tratamentos e três repetições. Foram fornecidas dietas com 29,0% PB, 2.980 kcal/kg de energia digestível (ED e quatro níveis de fósforo disponível (0,25; 0,35; 0,45 ou 0,55%, obtidos pela utilização de fosfato bicálcico como fonte de fósforo. As dietas foram fornecidas aos peixes três vezes por dia, até aparente saciedade, durante 46 dias. Não foi observado efeito dos níveis de fósforo disponível na dieta sobre o índice hepatossomático, a taxa de sobrevivência e os teores de água e proteína bruta na carcaça. O aumento dos níveis de fósforo disponível na dieta promoveu aumento linear do ganho de peso médio, da excreção de fósforo e dos teores de cinza na carcaça e de cinzas, cálcio e fósforo nos ossos. Houve efeito quadrático dos níveis de fósforo disponível sobre o consumo de ração, a conversão alimentar e a taxa de eficiência protéica, que foram melhores nos níveis 0,37; 0,48 e 0,48% de fósforo disponível, respectivamente. A exigência de fósforo disponível para tilápia-do-nilo de 35 a 100 g é de 0,48% (0,53% na matéria seca.The objective of this work was to determine the available phosphorus requirement of Nile tilapia. A total of 144 fishes with initial weight 35.33 ± 0,66g LW were distributed to a completely randomized blocks design, with four treatments and three replicates. Diets with 29.0% CP and 2980 kcal/kg DE and four available phosphorus levels (0.25; 0.35; 0.45 e 0.55% were used. The dicalcium phosphate was used as phosphorus source. The diets were fed to the fishes three times a day to apparent satiation, during 46 days. No significant effect of dietary available phosphorus on hepatosomatic index, survival rate and carcass water and protein contents were observed. The

  15. Digestibilidade de nutrientes em ração com complexo enzimático para tilápia-do-nilo Nutrient digestibility in diets with enzyme complex for Nile tilapia

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    Giovanni Resende de Oliveira

    2007-12-01

    Full Text Available Um ensaio de digestibilidade foi conduzido para avaliar os efeitos da suplementação de ração com um complexo enzimático contendo celulase, protease e amilase sobre a digestibilidade dos nutrientes em juvenis de tilápia-do-nilo (Oreochromis niloticus. As rações experimentais eram isoprotéicas (30% PB, isoenergéticas (4.243 kcal/kg EB e foram suplementadas com complexo enzimático comercial contendo celulase, protease e amilase nos níveis de 0,0; 0,025; 0,050; 0,075 e 0,1%. A determinação da digestibilidade aparente foi realizada pelo método indireto, com uso de óxido de cromo (Cr2O3 como indicador de digestibilidade. Foram utilizados 50 juvenis machos de tilápia-do-nilo (90 ± 15 g distribuídos aleatoriamente em dez incubadoras adaptadas para ensaio de digestibilidade. O experimento foi conduzido em três períodos experimentais, com cinco tratamentos e duas repetições por período. A adição do complexo enzimático à ração melhorou o coeficiente de digestibilidade aparente de matéria seca, proteína bruta, energia bruta, amido, cácio e fósforo. Entre os níveis testados, o de 0,05% de complexo enzimático proporcionou os valores mais expressivos.A digestibility trial was conducted to evaluate the effects of the supplementation of the ration with a enzyme complex containing cellulase, protease and amylase on the digestibility of nutrients in Nile tilapia juveniles (Oreochromis niloticus. The experimental diets were isoprotein (30% CP, isoenergy (4,243 kcal/kg of GE and supplemented with a commercial enzyme complex containing cellulose, protease and amylase at the levels of 0.0, 0.025, 0.050, 0.075, and 0.1%. The apparent digestibility was determinated by the indirect method using chrome oxide (Cr2O3 as an indicator of digestibility. A total of 50 male Nile tilapia juveniles (90 ± 15 g were randomly allotted to ten hatchers adapted for the digestibility trial. The experiment was conducted in three experimental periods

  16. Rações orgânicas suplementadas com farinha de resíduos de peixe para juvenis da tilápia do Nilo (Oreochromis niloticus Organic diet supplemented with fish residuum flour for Nile tilapia juveniles

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    Wilson Rogério Boscolo

    2010-12-01

    Full Text Available Objetivou-se com o presente trabalho avaliar a inclusão da farinha de resíduo da indústria de filetagem de peixes em rações orgânicas para tilápias do Nilo (O. niloticus na fase de crescimento, sobre o desempenho zootécnico (ganho de peso, conversão alimentar e sobrevivência, características de carcaça (rendimento de carcaça, tronco limpo, filé, gordura visceral, e índice hepatossomático e composição química (umidade, proteína bruta, matéria mineral e extrato etéreo dos peixes. Utilizaram-se 440 tilápias com média inicial de 84,11 ± 11,56 g de peso e 16,7 ± 0,80 cm de comprimento distribuídas em 20 tanques de 8 m³, em um delineamento inteiramente casualizado com cinco tratamentos e quatro repetições. Foram elaboradas cinco rações com níveis de 0; 4; 8; 12 e 16% de inclusão de farinha de resíduos com 28% de proteína digestível e 3.100 kcal kg-1 de energia digestível. Houve aumento linear nas médias de ganho de peso e redução linear na conversão alimentar com a inclusão da farinha. Não foram observadas diferenças significativas (P > 0,05 nos parametros de rendimento corporal, na umidade e proteína bruta dos filés, porém, a matéria mineral e o extrato etéreo apresentaram diferenças (P This work was carried out to evaluate the inclusion of fish by-product from the filleting industry in organic food for Nile tilapia (O. niloticus in the phase of growth, on livestock performance (weight gain, food conversion and survival, characteristics of carcass (carcass yield, clear trunk, fillet, visceral fat and hepatosomatic index and chemical composition (humidity, gross protein, mineral matter and ethereal extract of fish. A total of 440 tilapias with 84.11 ± 11.56 g average initial weight and 16.7 ± 0.80 cm in length, assigned into 20 8m³-aquaria, in a completely randomized design with five treatments and four replications. Four diets were prepared with levels of 0; 4; 8; 12 and 16% of fish by

  17. Utilização de levedura íntegra e seus derivados em dietas para juvenis de tilápia do Nilo Utilization of sugar cane yeast and its by-products in Nile tilapia diets

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    Ligia Uribe Gonçalves

    2010-05-01

    Full Text Available Neste trabalho, avaliou-se a adição de células íntegras de levedura e seus derivados em dietas para juvenis de tilápia do Nilo. Foram utilizados 144 juvenis machos de tilápia (peso médio de 52,1g distribuídos em 12 tanques de fibra de vidro (250L, em delineamento inteiramente casualizado, composto por quatro tratamentos e três repetições. Os peixes foram alimentados ad libitum, duas vezes ao dia durante 60 dias, com dietas isoproteicas (28% PB e isocalóricas (2.900kcal de ED kg-1 contendo levedura íntegra de cana-de-açúcar (LI, levedura autolisada (LA e parede celular (PC adicionados na proporção de 25% da proteína bruta total, comparadas com uma dieta controle (CO, sem adição de levedura. Não foram observadas diferenças significativas para conversão alimentar aparente e taxa de eficiência protéica. No entanto, o ganho em peso foi melhor nos peixes alimentados com as dietas LA (114,70g e PC (131,03g, assim como em relação à taxa de crescimento específico (LA=1,79 e PC=1,93%, à proteína bruta no ganho de peso (LA=14,45 e PC=15,62% e ao conteúdo corporal proteico (LA=14,89 e PC=15,67g 100g-1. As frações, a parede celular e a levedura autolisada de cana-de-açúcar podem ser utilizadas em dietas para juvenis de tilápia.This study has evaluated the effect of adding dried yeast and its by-products in diets for juveniles of Nile tilapia. It was used 144 juveniles of male tilapia (average weight of 52.1g distributed in 12 fiberglass tanks (250L, in completely randomized design, composed by 4 treatments and 3 replicates. The fish were fed ad libitum, 2 times per the day during 60 days, with isoproteic (28% CP and isocaloric diets (2.900kcal ED kg-1 with dried yeast of sugar cane (LI, disrupted yeast cells (LA and yeast cell wall (PC added in the ratio of 25% of the total crude protein, compared with a control diet (CO, without yeast addition. No significant differences were observed for feed conversion and proteic

  18. Fitase na alimentação da tilápia do Nilo (Oreochromis niloticus. Desempenho e digestibilidade Phytase as feeding for Nile tilapia (Oreochromis niloticus. Performance and digestibility

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    Wilson Massamitu Furuya

    2001-06-01

    Full Text Available Este experimento foi realizado para avaliar os efeitos da adição de diferentes níveis de fitase (0, 500, 1500 e 3000 unidades de fitase ativa [UFA]/kg de ração em dietas para a tilápia do Nilo (8,88 ± 0,02 g. Todas as rações foram fornecidas até saciedade durante 45 dias. O nível de fitase baseou-se nos parâmetros de desempenho e digestibilidade e foi estimado pelos modelos quadrático e/ou LRP ("broken line". De acordo com os resultados obtidos com os níveis de fitase, o modelo LRP apresentou o melhor ajustamento de dados. A suplementação de fitase aumentou o desempenho, a retenção de minerais nos ossos, a digestibilidade da proteína e a disponibilidade de cálcio e fósforo. Os melhores resultados de desempenho, retenção de minerais nos ossos e digestibilidade foram obtidos com 700 UFA/kg de ração.This experiment was carried out to evaluate the effects of addition of different levels of phytase (0, 500, 1500 and 3000 units of active phytase [UFA]/kg diet in the diets for Nile tilapia (8.88 ± 0.02 g. All diets were fed to satiation daily for 45 days. The phytase level determination was based on the performance and digestibility parameters and was estimated by the quadratic and/or the broken line models. The broken line model showed a better adjustment for phytase levels according to the observed results. Phytase supplementation increased performence, bone minerals, protein digestibility and calcium and phosphorus availability. The best results of performance, bone mineral retentions and digestibility were obtained with 700 UFA/kg of diet.

  19. Exigência de treonina, com base no conceito de proteína ideal, de alevinos de tilápia-do-nilo Digestible threonine requirement of Nile tilapia fingerlings using ideal protein concept

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    Marcos Antonio Delmondes Bomfim

    2008-12-01

    Full Text Available Avaliou-se o efeito dos níveis de treonina digestível, com base no conceito de proteína ideal, em rações com 1,35% de lisina digestível sobre o desempenho de alevinos de tilápia-do-nilo (Oreochromis niloticus. Utilizaram-se 432 alevinos revertidos de tilápia, linhagem tailandesa, com peso inicial de 1,64 ± 0,03 g, em delineamento inteiramente ao acaso, com seis tratamentos, cada um com seis repetições, e doze peixes por unidade experimental. Os tratamentos consistiram de cinco rações com diversas relações treonina:lisina digestível (69,0; 74,0; 79,0; 84,0 e 89,0% e relação metionina + cistina:lisina digestível de 70,0% e uma ração com relação treonina:lisina digestível de 84,0% e de metionina + cistina:lisina digestível de 75,0%, todas isoenergéticas e isoprotéicas. Os peixes foram mantidos em 36 aquários de 130 L, dotados de abastecimento de água, temperatura controlada e aeração individuais, e alimentados à vontade, seis vezes ao dia, durante 30 dias. Avaliaram-se o desempenho, a composição corporal, as deposições de proteína e gordura e a eficiência de retenção de nitrogênio dos peixes. O consumo de ração, o teor de proteína corporal e a deposição de proteína corporal aumentaram de forma linear de acordo com a relação treonina:lisina na ração, contudo, não foram influenciados pelo aumento da relação metionina + cistina:lisina da ração. Os níveis de treonina total ou digestível que proporcionaram os melhores resultados de desempenho em alevinos de tilápia-do-nilo foram de 1,11 e 0,99%, enquanto os níveis que promoveram melhor deposição de proteína corporal foram de 1,43 e 1,28%, que correspondem às relações treonina:lisina total de 71,0 e 69,0% e treonina:lisina digestível de 90,0 e 89,0%.The effects of digestible threonine levels, based on ideal protein concept in diets with 1.35% of digestible lysine on Nile tilapia (Oreochromis niloticus fingerlings performance. Four hundred

  20. Níveis de lisina digestível em rações para alevinos de tilápia-do-nilo Digestible lysine level in feed for Nile tilapia fingerlings

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    Sylvia Sanae Takishita

    2009-11-01

    Full Text Available Avaliaram-se níveis de lisina digestível em rações para alevinos de tilápia-do-nilo (Oreochromis niloticus, linhagem tailandesa, com base no conceito de proteína ideal. Utilizaram-se 432 alevinos com peso inicial de 0,98 ± 0,03 g, distribuídos em delineamento inteiramente casualizado, com 6 tratamentos, 6 repetições e 12 peixes por unidade experimental. Os tratamentos constaram de seis rações isoenergéticas (3.000 kcal de ED/kg de ração e isoproteicas (39,14% de PB contendo 1,50; 1,66; 1,82; 1,98; 2,14 ou 2,30% de lisina digestível. Foram avaliados o consumo de ração, o consumo de lisina digestível, o ganho de peso, a taxa de crescimento específico, a taxa de sobrevivência, a conversão alimentar, as taxas de deposição diária de proteína e gordura corporais, a composição química corporal (teores de umidade, proteína e gordura corporais e a eficiência de retenção de nitrogênio. O consumo de lisina digestível, a conversão alimentar, a porcentagem de proteína corporal e a deposição de proteína corporal melhoraram de forma linear de acordo com o nível de lisina digestível. O modelo Linear Response Plateau foi o de melhor ajuste para consumo de ração, ganho de peso, taxa de crescimento específico e eficiência de retenção de nitrogênio e estimou em 2,06; 2,17; 2,14 e 2,12%, respectivamente, os níveis de lisina digestível para melhorar cada um desses parâmetros. A exigência de lisina digestível e total em rações para alevinos de tilápia-do-nilo é, respectivamente, de 2,17% (0,723%/Mcal de energia digestível e de 2,32% (0,773%/Mcal de energia digestível para atender às principais características de desempenho e de carcaça utilizando-se o conceito de proteína ideal na formulação das rações.The effect of digestible lysine levels was evaluated in diets for Nile tilapia fingerlings (Oreochromis niloticus, Thailand lineage, based on the ideal protein concept. Four hundred and thirty two Nile

  1. Influence of diets enriched with different vegetable oils on the performance and fatty acid profile of Nile tilapia (Oreochromis niloticus fingerlings = Influência das dietas contendo diferentes óleos vegetais na performance e perfil em ácidos graxos de alevinos de tilápia do Nilo (Oreochromis niloticus

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    Nilson Evelázio de Souza

    2006-07-01

    Full Text Available The fatty acid profile of the carcass of Nile tilapia (Oreochromis niloticus fingerlings fed diets enriched with different soybean, canola, sunflower, flaxseed, rice, and corn oils was examined. The results showed that palmitic (16:0, stearic (18:0, oleic (18:1n-9, linoleic (18:2 n-6, and linolenic (18:3 n-3 acids were the predominant fatty acids in all vegetable oil, diet, and fish carcass samples analyzed. Flaxseed oil presented the highest amount of linolenic acid (45.63%, while the other vegetable oils had percentages lower than 5.0%. Neither of the vegetable oils used affected the performance of tilapia fingerlings and they can be utilized in Nile tilapia fingerling diets. However, in relation to the carcass fatty acid profile, the use of flaxseed oil in Nile tilapia fingerling diet is recommended. Foram examinados o perfil de ácidos graxos nas carcaças de alevinos de tilápia do Nilo (Oreochromis niloticus alimentados com dietas enriquecidas com diferentes óleos vegetais (soja, canola, girassol, linhaça, arroz e milho. Os resultados indicaram que o ácido palmítico (16:0, esteárico (18:0, oléico (18:1n-9, linoleico (18;2n-6 e linolênico (18:3n-3 foram os ácidos predominantes em todas as frações analisadas (no óleo vegetal, dietas e carcaças dos peixes. O óleo de linhaça apresentou o maior valor de ácido linolênico (45,63%, quanto aos outros óleos vegetais tiveram uma percentagem menor que 5,0%. Todos os óleos vegetais não afetaram a performance dos alevinos e podem ser utilizados nas dietas, entretanto, em relação a qualidade nutricional o uso do óleo de linhaça é recomendado em dietas de alevinos de tilápia.

  2. 2007-2012年中国罗非鱼无乳链球菌流行菌株血清型分析%Serotype of Streptococcus agalactiae isolated from Nile tilapia Oreochromis niloticus in China from 2007 to 2012

    Institute of Scientific and Technical Information of China (English)

    李莉萍; 甘西; 陈明; 王瑞; 黄婷; 梁万文; 雷爱莹; 李健; 黄维义; 唐佳有; 施金谷

    2014-01-01

    采用PCR血清型鉴定方法,对2007-2012年从广西、广东、海南、福建和云南等地养殖的罗非鱼Oreochromis niloticus中分离获得的168株无乳链球菌Streptococcus agalactiae流行菌株的血清型进行分析。结果表明:有159株为Ⅰa血清型,6株为Ⅰb血清型,3株为Ⅲ血清型。各区域流行菌株血清型也存在差异:从广西自治区7个地区50个养殖场的罗非鱼中分离的61株无乳链球菌中,有54株为Ⅰa型,4株为Ⅰb型,3株为Ⅲ型;从广东省10个地区59个养殖场的罗非鱼中分离的64株无乳链球菌中,有63株为Ⅰa型,1株为Ⅰb型;从海南省5个地区26个养殖场的罗非鱼中分离的33株无乳链球菌中,有32株为Ⅰa型,1株为Ⅰb型;从福建省漳州6个养殖场的罗非鱼中分离的6株和从云南省文山4个养殖场的罗非鱼中分离的4株均为Ⅰa型。研究表明,2007-2012年中国罗非鱼链球菌病流行菌株血清型存在Ⅰa、Ⅰb和Ⅲ3种血清型,Ⅰa型为主要血清型,研究结果可为准确分析中国罗非鱼链球菌病流行规律和特点提供数据,为该病防治及疫苗候选菌株筛选提供理论基础。%PCR typing assay was used to evaluate serotype of 168 Streptococcus agalactiae prevalent strains isolated from Nile tilapia Oreochromis niloticus in Guangxi,Guangdong,Hainan,Fujian and Yunnan provinces in China from 2007 to 2012. There were 159 strains ofⅠa,6 strains ofⅠb, and 3 strains of Ⅲ, with differences in serotypes of isolates from different regions. In the 61 strains isolated from 50 farms in 7 regions in Guangxi,54 strains wereⅠa, 4 strains Ⅰb, and 3 strains Ⅲ. There were 64 strains isolated from 59 farms in 10 regions in Guangdong, with 63 strains of Ⅰa,1 strain of Ⅰb. Thirty-three strains were isolated from 26 farms in 5 regions in Hannan, including 32 strains of Ⅰa, and 1 strains ofⅠb. Four strains ofⅠa were isolated from 6 farms in Zhangzhou in Fujian and Wenshan in Yunnan

  3. Cloning and analysis of the full-length cDNA sequences of the heat shock protein 70 gene from silver carp, grass carp and Nile tilapia%鲢鱼、草鱼和尼罗罗非鱼热休克蛋白70基因cDNA全序列的克隆与分析

    Institute of Scientific and Technical Information of China (English)

    何珊; 梁旭方; 李观贵; 王琳; 郁颖

    2009-01-01

    采用RT-PCR技术和RACE技术分别从淡水食毒藻鱼类鲢鱼(Hypophthalmichthys molotrix)、尼罗罗非鱼(Oreochromis nilotica)及草食性鱼类草鱼(Ctenopharyngodon idella)肝脏扩增出热休克蛋白70(HSP70)cDNA全序列,并与其它鱼类、两栖类和哺乳类动物的HSP70氨基酸进行了同源性比较.结果表明,鲢鱼、草鱼和尼罗罗非鱼肝脏HSP70基因cDNA全长分别为2356 bp、2348 bp和2242 bp,分别编码649、649和638个氨基酸.鲢鱼、草鱼和尼罗罗非鱼HSP70与其它鱼类、两栖类和哺乳类动物HSP70氨基酸同源性均较高,表明其在进化上高度保守,且承担着重要的生理功能.构建系统进化树发现,鲢鱼、草鱼与其它鲤科鱼类斑马鱼、银鲫(Carassius auratils gibelio)的HSP70氨基酸同源性较高,处于同一进化树分枝;而尼罗罗非鱼HSP70未与其它鲈形目鱼类,如鲷科鱼类聚为一枝,而是占据一个独立的分枝,这与克隆得到的鲢鱼、草鱼肝脏HSP70基因可能为结构型HSP70,而尼罗罗非鱼肝脏HSP70基因可能为诱导型HSP70的结果相一致.%Heat shock protein 70 ( HSP70) full-length cDNAs were cloned from the liver of two phytoplanktivorous freshwater fish, silver carp (Hypophthalmichthys molitrix) and Nile tilapia (Oreochromis nilotica) , and one herbivorous fish, grass carp (Cunopharyngodon idella) using RT-PCR and RACE. Sequence analysis revealed that the silver carp, grass carp, and Nile tilapia HSP70 cDNAs were 2356, 2348, and 2242 bp in length, and contained an open-reading frame ( ORF) of 1950 bp ( encoding a polypeptide of 649 amino acids) , 1950 bp ( encoding a polypeptide of 649 amino acids), 1917 bp (encoding a polypeptide of 638 amino acids), respectively. Silver carp, grass carp and Nile tilapia HSP70 sequences are highly homologous to other fish, amphibia and mammals HSP70, which suggests that they play a role in fundamental cellular processes. Results of the phylogenetic analysis revealed that silver carp

  4. Growth and Survival Rate of Tilapia (Oreochromis niloticus Larvae Fed by Daphnia magna Cultured With Organic Fertilizer Resulted From Probiotic Bacteria Fermentation

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    Vivi Endar Herawati

    2015-10-01

    Full Text Available Daphnia magna is a potential feed for fish. The aim of this research was to find the best treatment and effect of D. magna culture addition from fermented organic fertilizer, to growth and survival rate of Oreochromis niloticus larvae. There were five treatments, each with three repetitions used in the study. All treatments used chicken dung, and different combinations of rice bran, coconut oilcake waste and tilapia larvae. Feeding on tilapia was given by ad libitum method for five times a day until 14 days. Water quality during the research was maintained at temperature 28–29°C, DO 0.3 ppm and pH 8.1–8.2. Observed variables include relative growth rate, survival rate, food consumption rate and water quality. Our results showed that D. magna cultured by fermented organic fertilizer for tilapia larvae (O. niloticus had high significant effect (p < 0.01 on the relative growth rate and survival rate. Treatment of D. magna cultured by 1.2 g/L chicken manure, 0.9 g/L rice bran and 0.3 g/L coconut oilcake showed the highest value on the relative growth rate (10.86%; survival rate (98.46% and food consumption at first week (106.43% and second week (152.76%.

  5. 水库鲮和罗非鱼谷胱甘肽转移酶基因表达量与水中蓝藻含量的关系%Relationship between GST gene expression of mud carp (Cirrhina molitorella ) and Nile tilapia (Oreochromis niloticus )and composition of algae in Xiangang Reservoir

    Institute of Scientific and Technical Information of China (English)

    李玺洋; 梁旭方; 程炜轩; 瞿春梅; 张进

    2012-01-01

    采用荧光定量的方法对不同季节广州显岗水库鲮(Cirrhinus molitorella)和尼罗罗非鱼(Oreochromis niloticu)肝脏中去毒酶基因谷胱甘肽转移酶GST基因的表达情况,并结合不同季节鱼类摄入蓝藻量进行研究,旨在了解鱼体中GST基因的表达量与水体中蓝藻含量的内在联系.结果表明,4月份水库蓝藻暴发,也是鲮和尼罗罗非鱼摄食产毒蓝藻量最多的月份.GST基因的表达情况是:4月份鲮GST基因表达量比其他月份低,可能与鲮对有毒蓝藻的敏感性和耐受力有关,4月份尼罗罗非鱼GSTA及GSTR2表达量最高;其他月份,鲮GSTT表达量最高,而GSTK表达量较低,尼罗罗非鱼GSTA及GSTR2表达量相对较低.结果表明鲮GSTT在去毒过程中起重要作用,但作为环境检测的生物标记,仅适用于环境中藻毒素较低的情况.尼罗罗非鱼GSTA和GSTR2的表达量与食物中的产毒蓝藻生物量多少成正比,因此,尼罗罗非鱼GSTA及GSTR2可作为环境中藻毒素的生物标记,且尼罗罗非鱼可摄入大量有毒蓝藻,通过GST基因去除有毒蓝藻毒性,可用于生物控藻,改善水质.%To study the relationship and the intrinsic link between the expression of liver GSTCglu-tathione S-transferases) gene in mud carp(Cirrhinus molitorella) and Nile tilapiaiOreochromis nilotic-us) and the amount of cyanobacteriad,the expression of liver GST gene from the two fishes were analyzed using real-time RT-PCR and the amount of cyanobacteria intake of fish were determined in Xianga-ng Reservoir in different seasons. The results showed that April was the time that cyanobacteria bloomed,and simultaneously,mud carp and Nile tilapia intake the largest amount of toxic cyanobacteria. The GST genes in mud carp were expressed significantly lower in April than the rest time of the year, which suggested that mud carp may be resistant or tolerant totoxic cyanophyta. Both GSTA and GSTR2 genes in Nile tilapia had the highest expression in

  6. Long-term GnRH-induced gonadotropin secretion in a novel hypothalamo-pituitary slice culture from tilapia brain.

    Science.gov (United States)

    Bloch, Corinne L; Kedar, Noa; Golan, Matan; Gutnick, Michael J; Fleidervish, Ilya A; Levavi-Sivan, Berta

    2014-10-01

    Organotypic cultures, prepared from hypothalamo-pituitary slices of tilapia, were developed to enable long-term study of secretory cells in the pituitary of a teleost. Values of membrane potential at rest were similar to those recorded from acute slices, and cells presented similar spontaneous spikes and spikelets. Some cells also exhibited slow spontaneous oscillations in membrane potential, which may be network-driven. Long-term (6days) continuous exposure to GnRH induced increases in LH and FSH secretion. FSH levels reached the highest levels after 24h of exposure to GnRH, and the highest secretion of LH was observed in days 4 and 5 of the experiment. Since slices were viable for several weeks in culture, maintaining the original cytoarchitecture, electrical membrane properties and the ability to secrete hormones in response to exogenous GnRH, this technique is ideal for studying the mechanisms regulating cell-to-cell communication under conditions resembling the in vivo tissue organization.

  7. Disponibilidade aparente de fósforo em ingredientes pela tilápia-do-nilo (Oreochromis niloticus Apparent phosphorus availability in food for the Nile tilapia (Oreochromis niloticus

    Directory of Open Access Journals (Sweden)

    Edma Carvalho de Miranda

    2000-05-01

    Full Text Available Foi determinada a disponibilidade aparente do fósforo de ingredientes alimentares para a tilápia-do-nilo (Oreochromis niloticus. Foram utilizados 105 alevinos, revertidos, com peso vivo inicial médio de 16,0  0,5g. Foram distribuídas, cinco por aquário em 21 unidades de fibra de vidro (80L e sistema Guelf para coleta de fezes. Cada conjunto, constituído de três aquários, foi dotado de aeração, filtro biológico e fluxo contínuo (vazão de 0,75 L/mim. Foram avaliados o fosfato bicálcico, as farinhas de osso e de peixe, os farelos de soja e de trigo e fubá de milho, os quais substituíram parte de uma dieta purificada, usada como referência, marcada com óxido de crômio. Ao final, pode-se concluir: o fosfato bicálcico, disponibilidade aparente de 74,24%, deve ser a fonte preferencial de fósforo nas rações; a farinha de osso (54,59% apresenta-se como fonte alternativa; a de peixe apresentou baixa disponibilidade (27,15% e, dentre os produtos de origem vegetal, o farelo de soja apresentou a melhor (35,13%, e os farelos de trigo (30,49% e de milho, a pior disponibilidade (7,33%.Apparent availability of phosphorus from various foodstuffs for sexually reversed Nile tilapia (Oreochromis niloticus was provided. Fish with an average weight of 16.0  0.5g were randomly stocked in 21 aquariums equipped with feces collector (Guelf system, at the rate of five fish per aquarium. Each set of three aquariums was provided with a biological filter, aeration and flowing water (0.75 L/min discharge. An egg albumin-gelatin purified diet containing 0.1% chromic oxide was used as reference and basal diet. Dicalcium phosphate, bone and fish meals, soybean and wheat bran and middlings were added to the basal diet at 3.5, 6.0, 21.67, 40.0, 12.0 and 10.62% respectively, at the expense of albumin, gelatin and dextrose. Dicalcium phosphate was the best phosphorus source (apparent availability of 74.23% for tilapia fingerlings. In decreasing order it

  8. Molecular characterization and expression analyses of cDNAs encoding the thioredoxin-interacting protein and selenoprotein P genes and histological changes in Nile tilapia (Oreochromis niloticus) in response to silver nanoparticle exposure.

    Science.gov (United States)

    Thummabancha, Kubpaphas; Onparn, Nuttaphon; Srisapoome, Prapansak

    2016-02-15

    Herein, Nile tilapia thioredoxin-interacting protein (On-TXNIP) and selenoprotein P (On-SEPP) cDNAs were cloned and characterized. The full-length On-TXNIP cDNA contained 2 arrestin domains, 2 conserved cysteine residues that bind to thioredoxin to inhibit thioredoxin function, and 2 PPXY motifs, which negatively regulate the protein by stimulating binding to E3 ubiquitin ligase. The On-SEPP cDNA contained 17 selenocysteines (Sec) encoded by the TGA codon, which can be recognized as either a stop codon or a Sec codon. The On-SEPP cDNA also carried 2 typical SECIS elements located in the 3'UTR that are important for selenocysteine translation. Evolutionary analyses of both the On-TXNIP and On-SEPP genes revealed that these genes are closely related to the TXNIP and SEPP genes in zebrafish (Danio rerio), with amino acid similarities of 91.8% and 61.9%, respectively. A normal tissue distribution analysis indicated that the On-TXNIP and On-SEPP genes were ubiquitously expressed in all tissues examined, and the highest expression levels of these genes were observed in peripheral blood leukocytes (PBLs) and the trunk kidney, respectively. The expression levels of On-TXNIP and On-SEPP transcripts were acutely and chronically analyzed following the injection of fish with 1, 10 or 100mg/kg silver nanoparticles (Ag NPs). Significant up-regulation of On-TXNIP and On-SEPP transcripts was observed in the liver, spleen, and head kidney at the early phase of Ag NP exposure (hours 6 through 48). Down-regulation of On-SEPP transcripts was clearly observed in the liver at weeks 1 to 4. Histopathology analysis demonstrated that the fish livers exhibited a dramatic infiltration of Kupffer cells, elevated bi-nucleated cells, expanded sinusoidal blood congestion and severe necrosis in a dose-dependent manner. Based on these findings, coupling of the expression analysis of these two cellular stress response genes and histopathological observation of fish exposed to Ag NPs should be

  9. Chemical composition and digestibility of meal radish forage for Nile tilapia Composição química e digestibilidade do farelo de nabo forrageiro para tilápia do Nilo

    Directory of Open Access Journals (Sweden)

    Igo Gomes Guimarães

    2010-06-01

    Full Text Available This study was conduced at the FMVZ – Unesp - Botucatu, to determine the Chemical composition and apparent digestibility coefficient (ADC of dry matter (DM, crude protein (CP, raw energy (RE, amino acids (AA and phosphorus availability. The fish were fed with a purified feed (base diet and a 60% base diet plus 40% of fodder radish meal feed. Radish meal presented 91.28% DM, 42,07% CP, 4256 kcal/kg RE, 3.47% Ether extract, 7.37% crude fiber, 1.25% calcium and 1.0% phosphorus. The ADC values were DM: 55.92%, CP: 82.10%, RE: 75.26% and phosphorus: 85.23%. The ADC value for AA was 81.12% for glycine and 95.11% for glutamic acid. The results presented a potential utility for radish meal as an alternative protein source in Nile tilapia feeds.Este estudo foi realizado na Unesp - FMVZ -Botucatu, para determinar a composição química e os coeficientes de digestibilidade aparente (CDA da matéria seca (MS, proteína bruta (PB, energia bruta (EB, aminoácidos (AA e a disponibilidade do fósforo do farelo de nabo forrageiro, pela tilápia do Nilo. Empregou-se uma ração purificada (referência e uma ração composta de 60% da ração referência e 40% do farelo de nabo forrageiro. O farelo de nabo forrageiro apresentou 91,28% de MS; 42,07% de PB, 4256 kcal/kg de EB, 3,47% de extrato etéreo, 7,37% de fibra bruta, 1,25% de cálcio e 1,0% de fósforo. Os CDA foram de 55,92% para MS, 82,10% para PB, 75,26% para EB e 85,23% do fósforo. Os CDA dos AA estiveram entre 81,12% para a glicina e 95,11% para o ácido glutâmico. Os resultados demonstram que o farelo de nabo forrageiro apresenta potencial para ser usado como fonte proteica alternativa para compor a ração da tilápia do Nilo.

  10. Densidade de estocagem no desempenho de larvas de tilápia-do-Nilo (Oreochromis niloticus L., durante a reversão sexual Stocking density effect on Nile tilapia (Oreochromis niloticus L. fry performance during sex reversal

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    Luís Eduardo Ferrari Sanches

    1999-11-01

    Full Text Available Para estudar os efeitos da densidade de estocagem no desempenho de larvas de tilápia-do-Nilo, Oreochromis niloticus, durante a fase de reversão sexual em águas verdes, foram estocadas 1.500 larvas com peso médio de 12,41mg e comprimento total médio de 9,38mm em tanques-rede de 12,5 litros, nas densidades de 2, 4, 6, 8 e 10 larvas/litro, em delineamento totalmente aleatório com 4 repetições. Essas foram tratadas com ração comercial fina com 43% de PB, contendo 60mg de metiltestosterona/kg, 6 vezes por dia, durante 28 dias. O aumento da densidade resultou em menor peso e comprimento médios finais, definidos por modelos de regressão. O efeito da densidade sobre a diminuição do crescimento se evidenciou a partir da terceira semana de criação. A biomassa total e a conversão alimentar mostraram-se incrementadas com o aumento da densidade. A sobrevivência, o fator de condição e o coeficiente de variação foram independentes da densidade. Conclui-se que 2 larvas/litro devem ser usadas, quando se objetiva produção de alevinos maiores; mas densidades maiores podem ser utilizadas, obtendo-se alevinos menores, porém incrementando a biomassa total.To study the effects of stocking density on the performance of newborn fries of Nile tilapia Oreochromis niloticus, during sex reversal stage in green waters, 1500 fries were stocked with 12.41mg of average weight and 9.38mm of total average length in hapas of 12,5 litres, at densities of 2, 4, 6, 8 and 10 fries/litre, in a completely randomized design with 4 replications. They were fed with a fine commercial diet containing 43% CP, and 60mg of methyltestosterone/kg, six times a day, during 28 days. The density increase resulted in lower final average weight and length defined by regression models. The effect of density on the growth decrease started to be significative on the second week of rearing, while the total biomass and feed conversion were increased with the density increase

  11. Desempenho produtivo de tilápia do Nilo alimentada com níveis de colina na dieta = Growth performance of Nile tilapia fed graded choline levels in the diet

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    Ademir Calvo Fernandes Junior

    2010-04-01

    Full Text Available Este estudo foi realizado com o objetivo de avaliar o desempenho produtivo da tilápia do Nilo (Oreochromis niloticus alimentada com níveis de colina na dieta pelo período de 109 dias. Foram utilizados 192 alevinos com 4,0 ± 0,15 g de peso médio, distribuídos em 32 tanques-rede de 200 L, na densidade de seis peixes por tanque-rede, dispostos em aquários de 1.000 L. O delineamento experimental foi inteiramente casualizado com oito tratamentos e quatro repetições. As rações foram suplementadas com 0, 100, 200, 400, 600, 800, 1.000 e 1.200 mg de colina kg-1 de ração. Não foram observadas diferenças para ganho de peso, taxa de sobrevivência, conversão alimentar aparente, porcentagem de extrato etéreo do filé e do fígado, índice hepatossomático e concentração de lipídeos no plasma. Concluiuseque os diferentes níveis de colina não melhoraram o desempenho produtivo dos peixes nestas condições, pois a dieta basal supostamente supriu a exigência do peixe para colina.A 109-day feeding trial was undertaken aiming to evaluate the growth performance of Nile tilapia fed graded choline levels. One hundred and ninety-two (initial weight 4.0 ± 0.15 g fingerlings were distributed into 32 net cages (200 L each, four cages per treatmentand six fish per cage, placed in eight 1000L aquaria in a closed recirculation system. The treatments were assigned to the tanks comprising eight treatments and four replications arranged in a completely randomized experimental design. Diets were supplemented with choline chloride to provide 100, 200, 400, 600, 800, 1000, 1200 mg of choline per kg of feed and an unsupplemented diet. No significant differences were observed in growth performance, survival, apparent feed conversion, liver and fillet ether extract, hepatosomatic index and plasma lipid concentration, among treatments. Choline levels did not improve growth performance, possibly because the amount of choline in the diet had already met fish

  12. Quality index method (QIM application on shef life estimation of skinned fillets of Nile tilapia (Oreochromis niloticus kept in iceAplicação do método do índice de qualidade (MIQ para o estudo da vida útil de filés de tilápia do Nilo (Oreochromis niloticus sem pele, armazenados em gelo

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    Karoline Mikaelle de Paiva Soares

    2012-12-01

    Full Text Available The objective of this study was to develop the Quality Index Method (QIM for skinned fillets from farmed Nile tilapia (Oreochromis niloticus, and apply it in the establishment of its shelf life. The skinned fillets (120 g in average were kept in boxes with ice in the proportion of 1:1 (fillet:ice under average temperature of 0°C and stored at refrigeration chamber (4°C during 18 days. To evaluate the freshness during storage time sensory analysis (QIM and physicochemical (pH and TVB-N were performed every 72 hours from time zero, in triplicate. The maximum life of the Nile tilapia fillet in ice was estimated at 15 days. The MIQ was considered effective in evaluating the freshness of the Nile tilapia, since the sensory rejection by MIQ was determinant in the shelf life establishment. O objetivo do presente trabalho foi desenvolver o Método do Índice de Qualidade (MIQ para filé sem pele de tilápia do Nilo (Oreochromis niloticus, cultivada, e aplicá-lo no estabelecimento da sua vida útil. Os filés (média de 120 g cada foram mantidos em caixas com gelo na proporção de 1:1 (filé:gelo na temperatura média de 0°C e armazenados em câmaras de refrigeração (4°C por 18 dias. Para avaliar o frescor durante o armazenamento, realizaram-se análises sensoriais (MIQ e físico-químicas (pH e Nitrogênio das Bases Voláteis Totais a cada 72 horas, a partir do tempo zero, em triplicata. A vida útil máxima do filé sem pele de tilápia do Nilo, em gelo, foi estimada em 15 dias. O MIQ foi considerado eficiente na avaliação do frescor da tilápia do Nilo, já que a rejeição sensorial pelo MIQ foi determinante no estabelecimento da vida de prateleira.

  13. Exigência de metionina + cistina para alevinos de Tilápia do Nilo (Oreochromis niloticus Digestible methionine + cystine requirement for Nile Tilapia (Oreochromis niloticus, fingerlings

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    Wilson Massamitu Furuya

    2004-12-01

    Full Text Available Este estudo foi realizado para determinar a exigência de metionina + cistina para alevinos de tilápia do Nilo (2,61 ± 0,14g. Foi utilizado o modelo em blocos ao acaso, com seis tratamentos, três repetições e cinco peixes por unidade experimental. Foi utilizada ração basal contendo 28% de proteína bruta e 3173kcal ED kg-1 de ração, suplementada com DL-metionina, resultando em rações com 0,87; 0,95; 1,03; 1,11; 1,19 e 1,27% de metionina + cistina. As rações foram fornecidas à vontade durante 41 dias. Não foram observados efeitos (P>0,05 dos níveis de metionina + cistina sobre a taxa de sobrevivência e índice hepato-somático. Foi observado efeito quadrático (PThis study was carried out to determine the methionine + cystine requirement for Nile tilápia, fingerlings (2.61 ± 0.14g. A randomized block designs, with six treatments, three replicates and five fish by experimental unit was used. Basal diet was utilized with 28% crude protein and 3173DE kcal kg-1 of digestible energy, supplemented with DL-methionine, resulting in diets with 0.87; 0.95; 1.03; 1.11; 1.19 and 1.27% of methionine + cystine. Diets were fed to satiation during 41 days. No effects (P>0.05 of methionine + cystine levels on survival rate and hepatosomatic index were observed. A quadratic effect (P<0.05 for weight gain was observed, which increased up to 1.22% methionine + cystine in the diet. Feed conversion ratio and protein efficiency ratio increased (P<0.05 up to 1.00% of methionine + cystine. A quadratic effect (P<0.05 of methionine + cystine level on carcass yield was observed, which increased up to 1.13% of methionine + cystine. The concentration of 1.00% methionine + cystine corresponding to 3.54% crude protein, in the presence of 0.54% methionine in the diet, showed the best njperformance.

  14. Fibra bruta e óleo em dietas práticas para alevinos de tilápia do Nilo (Oreochromis niloticus Crude fiber and oil in diets for Nile tilapia (Oreochromis niloticus

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    Eduardo Arruda Teixeira Lanna

    2004-12-01

    Tilapia Nile. Twenty-four circular fishbowls of 250 liters, with an individual system of water replenishment and heating, were used. The stocking rate was of seven fishes/fishbowl, totalizing 168 fishes, with average initial weight of 6.41±0.05 g. Weight gain, apparent feed:gain ratio, specific growing rate and protein efficiency rate were evaluated. The chemical composition and carcass yield, eviscerated carcass and hepatossomatic index were also studied. A completely randomized design was used, in a 3 x 2 factorial scheme, being three crude fiber levels (6.00, 9.00%, and 12.00%, and two soybean oil levels (0.0 and 10.0%, with four replicates. It was verified that it is possible to use, in the diet, levels up to 12.00% of crude fiber and its excess tends to decrease the weight gain and the protein efficiency rate, besides worsening the feed:gain ratio; the fiber significantly affect the dietary apparent digestibility, with positive and negative effect on the protein and dry matter digestibility, respectively, and without effect on the ether extract digestibility; the crude fiber did not significantly affect the carcass yield and the eviscerated fat deposition. However, the oil addition to the diet showed significant effect on the eviscerated fat deposition; the fiber resulted in significant effect on the carcass chemical composition of the carcass (water and protein contents, without effect on the fat composition; and the fat addition to the diet significantly decreased and increased, respectively, the carcass protein and ether extract contents. It was concluded that, in the growing phase (from 6.40 to 31.00 g, the dietary crude fiber levels up to 9.00% can be fed for Nile tilapia and the supplementation of high dietary lipid levels decrease the carcass composition and result in higher eviscerated fat deposition.

  15. Digestibilidade Aparente da Energia e Nutrientes de Alimentos Convencionais e Alternativos para a Tilápia do Nilo (Oreochromis niloticus, L. Apparent Digestibility of the Energy and Nutrients of Conventional and Alternatives Foods for Nile Tilapia (Oreochromis niloticus

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    Wilson Rogério Boscolo

    2002-01-01

    Full Text Available O experimento foi conduzido com o objetivo de avaliar os coeficientes de digestibilidade aparente (CDa da matéria seca (MS, energia bruta (EB e proteína bruta (PB do farelo de soja (FS, milho (MO, trigo (TG, farelo de trigo (FT, milheto (MT, triticale (TC, farinha de varredura de mandioca (FM e óleo de soja (OS para tilápia do Nilo da linhagem tailandesa. Foram utilizados 100 animais revertidos sexualmente, com peso médio de 37,61 ± 4,98 g distribuídos em dois tanques de alimentação de 500L e coleta de fezes pelo sistema modificado de Guelph em dois aquários (150 L cada. A determinação dos CDa foi realizada pelo método indireto, sendo utilizado como indicador 0,1% de óxido de cromo (Cr2O3 incorporado à ração. Os CDa para a MS, PB e EB foram de 65,49, 89,58 e 71,38 para FS; 73,22, 93,40 e 76,63 para MO; 86,51, 96,30 e 87,07 para TG; 66,79, 91,00 e 68,81 para FT; 77,96, 94,91 e 89,12 para MT; 68,51, 94,78 e 80,55 TC; 91,11, 97,52 e 91,40% para FV, respectivamente; e para a EB do OS o CDa foi 89,85%, apresentando valores de proteína (% e energia (kcal/kg digestíveis de 42,19 e 3057,63 para FS; 7,18 e 3037,03 para MO; 11,01 e 3423,66 para TG; 13,44 e 2825,88 para FT; 13,88 e 3755,55 para MT; 13,74 e 3230,69 para TC; 1,76 e 3280,09 para FM, respectivamente, e 8485,28 kcal/kg de ED para o OS. Os resultados demonstraram que a tilápia do Nilo utiliza eficientemente a energia e proteína desses ingredientes. Os valores de energia e proteína digestíveis devem ser utilizados para elaborar rações completas.The trial aimed to evaluate the apparent strain digestibility coefficients (CDa of dry matter (MS, gross energy (EB and crude protein (PB of soybean meal (FS, corn (MO, wheat (TG, wheat meal (FT, millet pearl (MT, triticale (TC, cassava meal (FM and soybean oil (OS of Nile tilapia fingerlings of Thai. One hundred sexual reverted animals were used, with a mean weight of 37.61 ± 4.98g, distributed in two alimentation 500L mansory

  16. Farinha de vísceras de aves em rações para alevinos de tilápia do Nilo,Oreochromis niloticus (L. Poultry by-product meal in Nile tilapia (Oreochromis niloticus fingerlings diets

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    Anna Christina Esper Amaro de Faria

    2002-04-01

    digestibility of Nile tilapia fingerlings (Oreochromis niloticus fed diets with increasing levels of poultry by-product meal (PM were evaluated. Three hundred fingerlings with average initial weight of 0.35±0.01 g were placed in thirty 120 L net ponds in five cement 1000 L tanks. Six levels of PM inclusion (0.00, 4.00, 8.00, 12.00, 16.00 and 20.00% were used in the diets, in an experimental randomized blocks desing with six treatments and three replicates. An experiment of diet digestibility was undertaken with 0.00 and 20.00% PM diets on fish of average weight 47.81±9.97 g. A linear improvement was observed at PM inclusion levels with regard to final weight, percentage of weight gain, protein efficiency rate, nitrogen retention and quadratic effect for food conversion, ether extract retention and percentages of crude protein and carcass ethereal extract. Concerning to the digestibility experiment, the 20.00% PM diet showed lower coefficients of apparent digestibility for dry matter, crude protein, crude energy and higher coefficients for ether extract. However, higher values of digestible ether extract and energy were obtained with 20.00% PM diet, even though digestible protein was lower than the 0.00% PP diet. Apparent digestibility coefficients of the ether extract, crude protein and crude energy of PM for the Nile tilapia were 70.45, 63.93 and 55.89% respectively. Thus, the inclusion of 20.00% PM in diet improved performance, however increased ether extract content and decreased crude protein levels in carcass and dry matter, crude protein and energy digestibility coefficients of the diets.

  17. Desempenho de juvenis de tilápia-do-nilo alimentados com rações contendo complexo enzimático Performance of juvenile Nile tilapia fed diets with enzymatic complex

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    Arcangelo Augusto Signor

    2010-05-01

    Full Text Available Avaliou-se o efeito da inclusão de um complexo enzimático em dietas para tilápias-do-nilo (Oreochromis niloticus sobre o desempenho, a composição química da carcaça e a qualidade da água. Foram utilizados 200 alevinos revertidos (4,57 ± 1,24 g, distribuídos em delineamento inteiramente casualizado em 20 tanques de 500 litros, com quatro tratamentos e cinco repetições, considerando a unidade experimental uma caixa com dez peixes. Os peixes foram alimentados com dietas contendo 0; 0,033; 0,066 ou 0,099% de complexo enzimático. As dietas foram processadas na forma peletizada e fornecidas quatro vezes ao dia, às 8, 11, 14 e 17 h. Os valores médios de pH, condutividade elétrica, oxigênio dissolvido, temperatura, fósforo total, amônia e nitrato da água de cultivo não foram influenciados pela dieta. A inclusão do complexo enzimático na dieta não afetou o ganho de peso, as taxas de sobrevivência e de crescimento específico, mas influenciou o consumo de ração e a conversão alimentar, cujos valores foram maiores nos peixes alimentados com a dieta com 0,066% de complexo enzimático. Não foram observadas diferenças nos teores de matéria seca, umidade, proteína bruta, matéria mineral, cálcio e fósforo na carcaça dos peixes, no entanto, o teor de extrato etéreo reduziu de forma linear com o aumento do nível de complexo enzimático. A utilização de complexo enzimático (amilase, protease, celulase, lipase, pectinase, xilanase, β-glucanase e fitase no nível de 0,066% em dietas para juvenis de tilápia-do-nilo piora a conversão alimentar, mas não influencia o desempenho e a composição corporal dos peixes.The aim of this study was to evaluate the inclusion of an enzimatic complex in diets for Nile tilapia (Oreochromis niloticus on performance, carcass chemical composition as well as water quality. The experiment was performed in 62 days. It was used two hundred reverted fingerlings (14.57 ± 1.24 g distributed in a

  18. A tilapicultura e seus insumos, relações econômicas Tilapia culture and its inputs, economic relations

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    João Donato Scorvo Filho

    2010-07-01

    first one in South American production, supported basically by production chains of shrimp and tilapia culture. Brazil produced, in 2007, 95691.0 tons of tilapia, representing 45% of the continental aquaculture. Aquaculture from small and medium producers has shown in recent years changes on farming systems. By the end of the 90s, it was based on semi-intensive ponds and dams. From the year 2000, tilapia culture in cages highlighted, especially in Union waters (large reservoirs and hydroelectric dams in the Northeast Region. This change led to changes in the production chain, because adequate inputs to the system is needed: special diets, genetic material compatible with the rearing phases and production flow, since the new system has a higher scale of production. The agro-industrial system of fish covers two distinct production systems: a fishery system (extraction and aquaculture (production system. Some links in this system are shared by both systems, but food and genetic material are exclusive of aquaculture. Both systems interact with processing, distribution and marketing, and often compete with each other. Currently, Brazil has genetically improved strains, continuous process improvement and adaptation to our conditions. The activity of tilapia culture has increased through a process of professionalization, where the producer is closer to the used management and inputs. Today, producers can choose the input that best fits the management practices, but this is not a common practice when considering price.

  19. Eugenol como anestésico para a tilápia-do-nilo Eugenol as an anesthetic for Nile tilapia

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    Luiz Vítor Oliveira Vidal

    2008-08-01

    Full Text Available O objetivo deste trabalho foi avaliar o eugenol como anestésico para a tilápia-do-nilo. Para a concentração ideal, foram avaliados seis tratamentos (50, 75, 100, 150, 200 e 250 mg L-1, com dez peixes por tratamento, anestesiados individualmente, acompanhados durante a indução e recuperação. A toxicidade foi estimada pela submissão de 210 peixes a 7 concentrações de eugenol (50, 75, 100, 150, 200, 250, 300 mg L-1, durante 600 s e, para a margem de segurança, 120 peixes foram submetidos a 75 mg L-1 durante cinco intervalos de tempo (600, 1.200, 1.800 e 2.400 s. As concentrações eficientes foram 50 e 75 mg L-1. Os valores de toxicidade letal (CL, aos 600 s, foram: CL01, 81,97 mg L-1; CL50, 184,26 mg L-1; e CL99, 286,55 mg L-1; e os tempos de concentrações letais (TCL foram: TCL01, 566,97 s; TCL50, 1.611,66 s; e TCL99, 2.656,34 s. Concluiu-se que 75 mg L-1 são suficientes para a anestesia profunda de curta duração, com margem de segurança de 484,27 s, e 50 mg L-1 para longos períodos (600 s. A maior concentração terapêutica do eugenol custa R$ 0,065 por litro de água. A eutanásia pode ser realizada com 286,55 mg L-1 durante 600 s.The objective of this work was to evaluate eugenol as anesthetic for Nile tilápia. For the best concentration of the anaesthetic, six treatments (50, 75, 100, 150, 200, and 250 mg L-1 were evaluated, with ten fishes per treatment, anesthetised individually and monitored during the induction and recovery. Toxicity was estimated in 210 fish submitted to seven eugenol concentrations (50, 75, 100, 150, 200, 250, and 300 mg L-1 for 600 s; and for safety margin, 120 fish were submitted to 75 mg L-1 for five time intervals (600, 1,200, 1,800, and 2,400 s. The effective concentrations were 50 and 75 mg L-1. Lethal concentration (LC values for 600 s were: LC01 81.97 mg L-1, LC50 184.26 mg L-1, and LC99 286.55 mg L-1. Times of lethal concentration (TLC were TLC01 566.97 s, TLC50 1,611.66 s, and TLC99 2

  20. Hematological and immunological responses of Nile tilapia after polyvalent vaccine administration by different routes Resposta hematológica e imunológica de tilápia do Nilo após administração de vacina polivalente por diferentes vias

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    Bruno C. Silva

    2009-11-01

    Full Text Available The efficacy of a polyvalent bacterin vaccine against Aeromonas hydrophila, Pseudomonas aeroginosa and Enterococcus durans administered by different routes in Nile tilapia was assessed by analyzing hematological and immunological parameters 7 and 21 days after vaccination. Treatments consisted of: non-vaccinated tilapia; tilapia vaccinated by intraperitoneal injection with 2x10(8 formalin-inactivated bacteria·mL-1; tilapia vaccinated orally with 2x10(7 formalin-inactivated bacteria·g-1, feed for 5 days; tilapia vaccinated by immersion bath in 2x10(7 formalin-inactivated bacteria·mL-1, for 20 minutes. Vaccinated fish groups presented higher hematocrit, number of erythrocytes and leukocytes than the non-vaccinated group. Serum agglutination titer of intraperitoneally vaccinated fish was higher on both evaluation periods for the three bacteria strains. Only on day 21 post-vaccination fish from the oral and immersion vaccination groups presented higher serum agglutination titer than the non-vaccinated fish for A. hidrophyla and E. durans. Serum antimicrobial activity in vaccinated fish was higher for P. aeroginosa and E. coli than in non-vaccinated fish on both evaluation periods. The different vaccine administration routes stimulated hematological and immunological responses in Nile tilapia 21 days post-vaccination, but intraperitoneal vaccination presented higher total number of leukocytes, lymphocytes and serum agglutination titer.Este estudo avaliou a eficácia da administração de vacina polivalente (bacterina, contra Aeromonas hydrophila, Pseudomonas aeroginosa e Enterococcus durans, por diferentes vias de aplicação em tilápia do Nilo, analisando parâmetros hematológicos e imunológicos no 7º e 21º dia após vacinação. Os tratamentos consistiram de: tilápias não vacinadas; tilápias vacinadas via injeção intraperitoneal (i.p. contendo 2x10(8 bactérias inativadas·mL-1; tilápias alimentadas com ração contendo vacina na

  1. Qualidade do sêmen em tilápia do Nilo (Oreochromis niloticus, alimentadas com dietas contendo diferentes níveis de vitamina C = Semen quality in Nile tilapia (Oreochromis niloticus, fed with diets containing different vitamin C levels

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    Marcela Mataveli

    2010-07-01

    Full Text Available A vitamina C atua na proteção de danos celulares provocados pelos radicais livres, sendo a suplementação considerada essencial para a maioria das espécies de peixes, uma vez que não a sintetizam em função da ausência da enzima L-gulonolactona oxidase. Assim, avaliou-se o efeito da suplementação de 0, 75, 150 e 225 mg de vitamina C kg-1 de ração na qualidade do sêmen em tilápias do Nilo (Oreochromis niloticus. Os parâmetros quali-quantitativos do sêmen não foram influenciados pela suplementação de vitamina C, exceto a motilidade progressiva que aumentou linearmente com adição de vitamina C. Conclui-se que os reprodutores de tilápias do Nilo devem ser suplementados com 225 mg de vitamina C kg-1 de ração.Vitamin C acts as cellular protection from damage by free radicals, and vitamin C supplementation is considered essential for most fish species, as they do not synthesize it due to the absence of enzyme L-gulonolactone oxidase. Thus, the effect of supplementation with 0, 75, 150 and 225 mg of vitamin C kg-1 of ration was evaluated in the semen quality in Nile tilapia (Oreochromis niloticus. Seminal parameters were not influenced by vitamin C supplementation except progressive motility, which increased linearly with the addition of vitamin C. It was concluded that Nile tilapia reproducers should be supplemented with 225 mg vitamin C kg-1 ration.

  2. Diferentes fontes protéicas de origem vegetal para tilápia do Nilo (Oreochromis niloticus L. durante a reversão sexual - DOI: 10.4025/actascianimsci.v26i1.1929 Different protein vegetal sources for the Nile tilapia (Oreochromis niloticus L. during sexual reversion - DOI: 10.4025/actascianimsci.v26i1.1929

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    Eliana Maria Galdioli

    2004-04-01

    Full Text Available Com o objetivo de avaliar diferentes fontes protéicas de origem vegetal para a tilápia do Nilo durante a fase de reversão sexual, foram utilizadas 360 larvas distribuídas em 24 aquários (12 litros cada em um delineamento inteiramente casualizado com quatro tratamentos e seis repetições. Foram comparadas quatro fontes protéicas de origem vegetal, sendo o farelo de soja (FS, farelo de canola (FC, farelo de girassol (FG e farelo de algodão (FA. A uniformidade do lote, o fator de condição e a sobrevivência não foram afetadas pelos diferentes tratamentos. O FA levou aos piores resultados no peso e no comprimento final. A matéria seca da carcaça dos peixes alimentados com FG apresentou-se superior a do FS (p Three hundred and sixty Nile tilapia larvae were distributed in 24 12L-aquaria to evaluate different protein vegetal sources. Design was totally randomised with four treatments and six repetitions. Four protein vegetal sources were compared: soy meal (SM, canola meal (CM, sunflower meal (FG and cotton meal (TM. Uniformity of lots, condition factor and survival were not affected by the different treatments. TM had the worst results in weight and final length. Carcass dry matter of fish fed on FM was superior to SM (p < 0.05. Percentage of crude protein of carcass was highest in treatments CM and SM; the lowest percentage belonged to FM. SM, CM and FM may be used as protein vegetal sources without any impairment in the performance of Nile tilapia larvae.

  3. Producción de tilapia nilótica (Oreochromis niloticus L. utilizando hojas de chaya (Cnidoscolus chayamansa McVaugh como sustituto parcial del alimento balanceado Nile tilapia production (Oreochromis niloticus L. using tree spinach leaves (Cnidoscolus chayamansa McVaugh as a partial substitute for balanced feed

    Directory of Open Access Journals (Sweden)

    Gaspar R Poot-López

    2012-11-01

    with a limited food supply. In rural areas, the availability of alternative inputs is key to improving fish farming production, especially if these inputs are unprocessed. The leaves of tree spinach (Cnidoscolus chayamansa, a bush that grows in Mexico and Central and South America, are one such option. In this work, juvenile tilapia (7-4.5 g survival, growth rates, and food conversion rates were studied during two seasons (warm and cold, substituting 25 and 50% of the balanced feed rations with raw tree spinach leaves (ad libitum. The experimental design was completely random, with two treatments and one control (00% of the balanced feed ration; three replicates were done in each season. The densities were 36 fish m-per replica in the cold season and 44 fish m-3 per replica in the warm season. The weight gain in the treatments with 50 and 75% balanced feed and tree spinach leaves was similar to that of the control group in both seasons. The cold season adversely affected survival, weight gain, and feed conversion rates in all treatments, but the warm season did not. When tree spinach leaves were included in the tilapia diet, the feed conversion rate for the balanced feed was reduced from 9.7 to 33.62% in the cold season and from 5.38 to 40.23% in the warm season. The results show that the use of locally available complementary inputs such as tree spinach leaves may favor the development of small-scale tilapia cultures in the tropics.

  4. Reproductive biology of female Nile tilapia Oreochromis niloticus (Linnaeus) reared in monoculture and polyculture with African sharptooth catfish Clarias gariepinus (Burchell).

    Science.gov (United States)

    Shoko, A P; Limbu, S M; Mrosso, H D J; Mgaya, Y D

    2015-01-01

    This study was conducted to assess the reproductive biology and early breeding behaviour of female Oreochromis niloticus reared in monoculture and polyculture with Clarias gariepinus in earthen ponds for 8 months. Results revealed no significant difference in length at first maturity (L50) between females reared in monoculture and polyculture systems. Similarly, no significant differences were detected in absolute fecundity, relative fecundity, gonado-somatic index and condition factor between the two culture systems. The absolute fecundity was more strongly correlated with total length and body weight than with ovary weight. The study concluded that early breeding of O. niloticus in captivity is not affected by the culture systems used. Therefore, O. niloticus production in either system can be improved only through proper pond management techniques.

  5. Cultural heritage omni-stereo panoramas for immersive cultural analytics - From the Nile to the Hijaz

    KAUST Repository

    Smith, Neil

    2013-09-01

    The digital imaging acquisition and visualization techniques described here provides a hyper-realistic stereoscopic spherical capture of cultural heritage sites. An automated dual-camera system is used to capture sufficient stereo digital images to cover a sphere or cylinder. The resulting stereo images are projected undistorted in VR systems providing an immersive virtual environment in which researchers can collaboratively study the important textural details of an excavation or historical site. This imaging technique complements existing technologies such as LiDAR or SfM providing more detailed textural information that can be used in conjunction for analysis and visualization. The advantages of this digital imaging technique for cultural heritage can be seen in its non-invasive and rapid capture of heritage sites for documentation, analysis, and immersive visualization. The technique is applied to several significant heritage sites in Luxor, Egypt and Saudi Arabia.

  6. Productive performance and economic viability the juvenile of the Nile tilapia cultivated in the west of Paraná submitted to different stocking densities Desempenho produtivo e viabilidade econômica de juvenis de tilápia-do-Nilo cultivados na região oeste do Paraná sob diferentes densidades de estocagem

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    Affonso Celso Gonçalves Júnior

    2008-06-01

    Full Text Available It was aimed at with this work to evaluate the effect of the stocking density on the performance parameters, survival and economic viability of the production of juvenile of Nile tilapia (Oreochromis niloticus, Chitralada strain in half-intensive system, using twelve tank nurseries. 2700 juvenile sexually reverted with initial average weight of 0.65 g were distributed in an entirely randomized experimental design with four treatments (different stocking densities: 1, 2, 3, 4 peixes/m3 and three repetitions. During the tracking of the physical-chemical variables of the water, the pH (6.6 to 7.1 and the conductivity (24 μS/cm had presented satisfactory average values. However, the transparency (47 to 87 cm, the dissolved oxygen (3.09 to 4.60 mg/L and the temperature (19 to 24ºC had been outside of the normal standards recommended for the tropical fish culture. At the of the 84 days of culture the average daily mean weight (0.61 to 1.02 g/day and the specific growth (5.22 to 5.82% of the juveniles had presented a negative linear relationship (p<0.05 and the alimentary conversion (0.98 to 1.84 a quadratic relationship (p<0.01 in function to the stocking density. It was concluded that, in the conditions where these studies had been carried through, the stocking densities had influenced in the productive performance the juvenile of Nile tilapia, providing an increase in the ration consumption and consequently in the production cost. Through an economical analysis of the production the best economical viability is verified when used a density of up to 3 fish/m3.Objetivou-se com este trabalho avaliar o efeito da densidade de estocagem, sobre os parâmetros de desempenho e sobrevivência, e a viabilidade econômica da produção de juvenis de tilápia-do-Nilo (Oreochromis niloticus, linhagem Chitralada, em sistema semi-intensivo, utilizando-se doze viveiros escavados. 2700 juvenis sexualmente revertidos com peso médio inicial de 0,65 g foram distribu

  7. Produção de populações monossexo macho de tilápia-do-nilo da linhagem Chitralada Production of monosex male nile tilapia populations of the Chitralada strain

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    Adalmyr Morais Borges

    2005-02-01

    Full Text Available A fim de avaliar o efeito da alta temperatura na proporção de sexos da tilápia-do-nilo (Oreochromis niloticus da linhagem Chitralada, foram conduzidos dois experimentos. No primeiro foram analisados, por 28 dias, os efeitos da temperatura de 35ºC, em relação ao controle (27ºC, iniciando-se dez dias após a eclosão. Foi encontrada diferença significativa na proporção de sexos, sendo que o maior porcentual de machos foi encontrado no tratamento de temperatura alta (72,39%, em comparação com o controle (62,27%. Não foram encontradas diferenças de peso corporal e de comprimento total entre os tratamentos. No segundo experimento, foram analisados os efeitos dos períodos de exposição à temperatura de 35ºC, aos 7, 14, 21 e 28 dias, iniciando-se dez dias após a eclosão. Não houve diferença na proporção de sexos entre os períodos de exposição. Foram encontradas diferenças significativas entre os tratamentos, tanto para peso corporal como para comprimento total. Nos dois experimentos, as taxas de sobrevivência relacionaram-se diretamente com a ocorrência de canibalismo, significativamente maior a 35ºC. Os efeitos significativos da temperatura na proporção de sexos, no primeiro experimento, indicam a termossensibilidade na linhagem Chitralada.The effect of high temperature on sex ratio in the Chitralada strain of Nile tilapia (Oreochromis niloticus was tested using two experiments. Primarily, the animals were exposed to a high (35ºC or control (27ºC water temperature for a 28-day-period, beginning ten days after hatching. A significant difference in sex ratio was found. The highest proportion of males was in the high temperature group (72.39%, compared with the control group (62.27%. No differences were found for total length or body weight between the groups. In the second experiment, the effect of exposure times (7, 14, 21 and 28 days starting ten days post hatching at a constant temperature of 35ºC was tested. No

  8. Digestibilidade aparente de alguns alimentos protéicos pela tilápia do Nilo (Oreochromis niloticus Apparent digestibility of some protein sources for Nile tilapia (Oreochromis niloticus

    Directory of Open Access Journals (Sweden)

    Fábio Meurer

    2003-12-01

    Full Text Available Foi conduzido um ensaio de digestibilidade para determinar os coeficientes de digestibilidade aparente (CD da matéria seca (MS, energia bruta (EB e proteína bruta (PB da farinha de peixe (FP, farinha de vísceras de aves (FV, glúten de milho (GM e levedura de álcool spray dried (LS pela tilápia do Nilo, da linhagem tailandesa. Foram utilizados 100 peixes revertidos sexualmente, (peso médio de 37,6 ± 5,0 g acondicionados em dois tanques de alimentação de 500 L e duas cubas cilíndricas com fundo cônico, de 150 L, para coleta de fezes. A determinação dos CD foi feita por intermédio da metodologia indireta, tendo sido utilizado 0,1% de óxido crômico (Cr2O3, como indicador. As médias de temperatura, oxigênio dissolvido, pH e condutividade elétrica durante o período experimental foram de 25,8 ± 1,0ºC; 3,2 ± 1,4 mg/L; 6,8 ± 0,1; e 205,7 ± 16,6 µS/cm, respectivamente. Os CD da PB, EB e MS foram respectivamente de 90,66; 89,53 e 87,63 para FP; 82,03; 72,09 e 62,21 para FV; 97,61; 93,52 e 91,01 para GM; 77,39; 62,77 e 58,68 para LS. Os valores de proteína (% e energia (kcal/kg digestíveis, na matéria natural, de 53,01 e 3568,0 para FP; 47,65 e 3650,9 para FV; 65,34 e 5036,7 para GM e 32,19 e 2706,9 para LS.A digestibility trial was carried out to determine the dry matter (MS, gross energy (EB and crude protein (PB apparent digestibility coefficients (CD for fish meal (FP, poultry by-products meal (FV, gluten meal (GM and alchool spray dried yeast (LV for Thai Nile tilapia fingerlings. A hundred sexually reverted fishes (average weight 37.6 ± 5.0 g were assigned to two 500-L feeding tanks and two 150-L cylindrical tanks with conical bottom, to feces collection . CD analysis was performed by the indirect method, using 0.1% chromic oxide (Cr2O3, as marker. Average water temperature, dissolved oxygen, pH and conductivity were 25.8 ± 1.0ºC; 3.2 ± 1.4 mg/L; 6.8 ± 0.1; and 205.7 ± 16.5 µS/cm, respectively. CD of PB, EB and MS

  9. Predição do rendimento e do peso do filé da tilápia-do-Nilo = Prediction of yield and weight of Nile tilapia fillet

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    Aldrin Vieira Pires

    2011-07-01

    Full Text Available A criação de tilápia-do-Nilo (Oreochromis niloticus e o seu filé apresentam um mercado vigoroso e expansão no Brasil e no mundo. Portanto, um modelo de regressão obtido a partir de parâmetros corporais externos, de fácil observação, que prediga o rendimento e o peso do filé possibilita selecionar indivíduos com maior potencialprodutivo. Objetivou-se com este trabalho obter um modelo que permita predizer o rendimento e o peso do filé, baseado em medidas morfométricas e do peso. Foram avalidos 890 indivíduos dos quais os caractéres mensurados foram: comprimento total (CT, comprimento-padrão (CP, comprimento da cabeça (CC e do tronco (CTR, altura dacabeça (AC1, altura lombar (AL, altura caudal (AC2, espessura lombar (EL e caudal (EC, peso corporal (PESO, peso de filé (PF e rendimento de filé (RF. Foram realizadas análises de regressão linear, com PF e RF como variáveis dependentes. O R2 para o modelodo PF foi 0,80, demonstrando que as medidas corporais são confiáveis para se estimar o peso do filé. Já para o modelo do RF, o R2 foi de 0,16, não sendo adequado para se estimar o rendimento do filé, devendo ser desenvolvidos novos estudos para se obter um modelo maisconfiável.The rearing of Nile tilapia (Oreochromis niloticus and its fillet have shown a vigorous market expansion in Brazil and worldwide. Therefore, a regression model obtained from external physical parameters, of easy observation, which can predict the yield and weight of fillet, making it possible to select individuals with higher yield potential. The objective of this work was to obtain amodel that allows a prediction of fillet yield and weight, based on morphometric measurements and weight. Data were collected on 890 individuals and the measured characters were: total length (TL, standard length (CP, length of the head (CC and the stem (CTR, height of the head (CA1, lumbar height (AL, height flow (CA2, lumbar thickness (EL and throughput (EC, body

  10. Incorporação de ômega-3 no tecido muscular da tilápia do Nilo alimentada com dietas contendo silagem de cabeça de camarão Incorporation of n-3 in muscular tissue of Nile tilapia fed with shrimp head silage

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    Carolina Nunes Costa

    2012-01-01

    Full Text Available O objetivo deste estudo foi avaliar a incorporação de ômega-3 EPA (eicosapentaenóico e DHA (docosahexanóico no tecido muscular de tilápias do Nilo alimentadas com dietas suplementadas com diferentes níveis de silagem de cabeça de camarão Litopenaeus vannamei (0, 4, 8, 12, 16%. Foram analisados os teores de EPA, DHA e lipídios totais das dietas e dos tecidos musculares das tilápias. Os teores de lipídios totais variaram entre 6,70 a 10,30% nas dietas e 0,79 a 1,37% no tecido muscular. Através da análise de regressão, houve um aumento nos teores de ômega-3 (r=0,92 com a inclusão da silagem na dieta. Foi observada incorporação de 0,59% (1,34mg 100g-1 e 9,5% (40,50mg 100g-1 de EPA e DHA, respectivamente, no tratamento com 16% de silagem na dieta. A inclusão de 16% da silagem ácida de cabeça de camarão na dieta das tilápias aumentou significativamente os níveis de incorporação de EPA e DHA no filé.The aim of the present study was to assess the effect of diets supplemented with shrimp-head silage on the incorporation of n-3 in the Nile tilapia fillets. EPA (eicosapentaenoic, DHA (docosahexanoic and total lipids were determined by chromatography in feeds and the muscles of tilapia specimens were submitted to diets supplemented with a varying degree of silage (0, 4, 8, 12, 16%. The total lipid content ranged from 6.70 to 10.30% in the diets and from 0.79 to 1.37% in the tilapia fillets. In diet with high concentration of silage, it was observed an increase in the level of omega-3 (r=0.92. There was an incorporation of 0.59% (1.34mg 100g-1 and 9.5% (40.50mg 100g-1 of EPA and DHA, respectively, when the addition of silage to the diet was 16%. The results implication states that the inclusion of 16% of the shrimp head silage in the diet for tilapias increases the levels of incorporation of EPA and DHA in the filet.

  11. Mixed culture of tilapia (Oreochromis niloticus) and freshwater prawn (Macrobrachium rosenbergii) in periphyton-based ponds

    NARCIS (Netherlands)

    Uddin, S.

    2007-01-01

    In recent years, the concept of periphyton-based aquaculture has been tested and applied in aquaculture. Positive effects of substrate addition for periphyton development included increasing the food supply and providing shelter for culture animals. The aim of this project was to develop a low-cost

  12. Hematology and agglutination titer after polyvalent immunization and subsequent challenge with Aeromonas hydrophila in Nile tilapia (Oreochromis niloticus Hematología y título de aglutinación después de inmunización polivalente y desafío con Aeromonas hydrophila a tilapias del Nilo (Oreochromis niloticus

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    RL Bailone

    2010-01-01

    Full Text Available This study evaluated the effects of polyvalent vaccination on the hematological and serum agglutination responses in Nile tilapia challenged with Aeromonas hydrophila. Two dosis, 1 x 10(4 and 1 x 10(8 Colony Forming Units (CFU/mL, of vaccine containing the same amount of Aeromonas hydrophila, Pseudomonas aeruginosa and Enterococcus durans formalin-inactivated were tested by intraperitoneal (i.p injection. Fish were challenged ten days after vaccination i.p. with a DL50-96h of 1 x 10(7 CFU A. hydrophila/mL. Samples were collected 48 h after challenging fish to check the hematological parameters, antimicrobial activity and agglutination titer of serum, samples were collected 48 h after challenge. Before challenge, the number of erythrocytes was higher in fish vaccinated with 1 x 10(8 CFU/mL. After challenge, total number of thrombocytes was higher in fish that received the greatest dose of vaccine. Before and after challenge, total number of leukocytes and the number of lymphocytes showed the highest values in vaccinated fish. Before challenge, increased number of monocytes in vaccinated and saline-injected fish was observed. The highest agglutination titer against A. hydrophila, P. aeruginosa and E. durans was related in 1 x 10(8 CFU/mL vaccinated fish. Before challenge, high values of antimicrobial activity in non-vaccinated fish and 1 x 10(8 CFU/mL vaccinated ones was also related. Therefore, after challenge, non-vaccinated fish and saline-injected ones showed the highest antimicrobial activity. This study showed that 10 days after immunization with a polyvalent vaccine at a concentration 1 x 10(8 CFU/mL, there was an increase on erythrocytes, leukocytes, thrombocytes and circulating lymphocytes production, while the glucose levels were reduced.Este trabajo evaluó el efecto de la vacuna polivalente sobre las respuestas hematológicas y inmunológicas de tilapias del Nilo desafiadas con Aeromonas hydrophila. Dos dosis, 1 x 10(4 y 1 x 10

  13. Phenolic acids identified in sorghum distillery residue demonstrated antioxidative and anti-cold-stress properties in cultured tilapia, Oreochromis mossambicus.

    Science.gov (United States)

    Lee, Shin-Mei; Lin, Jing-Jen; Liao, Chih-Yuan; Cheng, Hui-Ling; Pan, Bonnie Sun

    2014-05-21

    This study aimed to identify the bioactive compounds and evaluate the anti-cold-stress function of the sorghum distillery residue (SDR) using tilapia as an alternative animal model. The highest contents of water-soluble bioactive compounds in SDR were polyphenols, followed by tannins, anthocyanins, and flavonoids. SDR was extracted with double-distilled water, 95% ethanol, and ethyl acetate, separately. The ethanol extract (SDR-E) yielded the highest polyphenol content [15.03 mg/g of SDR dry weight (dw)], of which the EC50 value of R,R-diphenyl-β-picrylhydrazyl (DPPH) radical scavenging efficiency was 0.56 ± 0.04 mg/mL. The SDR-E suppressed the oxidation of low-density lipoproteins (LDLs) more efficiently than that of other extracts. Tilapia fed a diet containing 3.6% SDR-E decreased accumulative mortality during cold stress, of 46.2%. The accumulative morality of the control was 92.9%. The phenolic acids identified in SDR included gallic acid (0.36 ± 0.08 mg/g of SDR dw), 3,4-dihydroxybenzoic acid (0.16 ± 0.12 mg/g of SDR dw), and 4-hydroxybenzoic acid (0.49 ± 0.23 mg/g of SDR dw). Diets supplemented with 0.5% 4-hydroxybenzoic acid fed to tilapia showed a lower mortality rate than that fed 1.0% 4-hydroxybenzoic acid, comparable to that of the tilapia fed 20% SDR. The latter showed lower mortality than that of the control. These results suggested that 4-hydroxybenzoic acid is one of the major anti-cold-stress compounds in SDR.

  14. Farinha de vísceras de aves em rações para a tilápia do Nilo (Oreochromis niloticus L. durante a fase de reversão sexual Poultry meal by-products in diets for Nile tilapia (Oreochromis niloticus L. in the reversion phase

    Directory of Open Access Journals (Sweden)

    Wilson Rogério Boscolo

    2005-04-01

    Full Text Available Neste trabalho, objetivou-se avaliar o desempenho, a sobrevivência e a efetividade de reversão de larvas de tilápia do Nilo (Oreochromis niloticus L. alimentadas com rações contendo níveis crescentes de inclusão de farinha de vísceras de aves (FVA. Utilizou-se 500 larvas de tilápia do Nilo com dois dias de idade, distribuídas em um delineamento inteiramente casualizado com cinco tratamentos e cinco repetições, sendo a unidade experimental constituída por um aquário de 30 L com 20 larvas. Foram elaboradas cinco rações com cinco níveis de inclusão de FVA ( 0; 20; 40, 60% e 60% mais lisina sintética. Foram elaboradas rações isocalóricas, isocálcicas, isofosfóricas e isoprotéicas, com 60mg de a-metiltestosterona/kg, 38,6% de proteína digestível e 3.700 kcal de energia digestível/kg, de modo que a ração com inclusão de lisina foi isoaminoacídica para lisina em relação à ração sem a inclusão de FVA. O arraçoamento foi realizado quatro vezes ao dia, ad libitum. Ao final, foram avaliadas as médias de peso final (PF, comprimento total (CT, sobrevivência (SO e efetividade de reversão (ER. Foi observado aumento linear no PF e CT com o aumento da inclusão da FVA na ração, enquanto, para SO, a ração sem FVA foi inferior às demais. As rações sem inclusão de FVA e com 20% de inclusão de lisina proporcionaram PF e CT médios inferiores e somente a ração sem FVA foi inferior para SO. Conclui-se que a FVA pode ser utilizada em rações para a tilápia do Nilo durante a reversão sexual.The objective of this work was to evaluate the performance, survival and effectiveness of reversion of Nile tilapia fry (Oreochromis niloticus L. fed with rations containing growing levels of inclusion of poultry by products (FVA. Five hundred Nile tilapia fry were used with two days of age, allotted to a completely randomized design with five treatments and five replications, and the experimental unit an aquarium 30 L with 20

  15. Farinhas de peixe, carne e ossos, vísceras e crisálida como atractantes em dietas para alevinos de tilápia do Nilo (Oreochromis niloticus Fish, meat and bone, poultry by-products and silkworm meals as attractive in diets for Nile tilapia (Oreochromis niloticus fingerlings

    Directory of Open Access Journals (Sweden)

    Wilson Rogério Boscolo

    2001-10-01

    Full Text Available O experimento foi conduzido com o objetivo de comparar a utilização de 5% de inclusão das farinhas de peixe (FP, vísceras (FV, carne e ossos (FO, crisálida (FC e controle (farelo de soja e milho como atractantes sobre o consumo de ração e desempenho de alevinos tilápia do Nilo. Foram utilizados 168 alevinos de tilápia do Nilo (linhagem tailandesa revertidos sexualmente, com peso inicial médio de 0,72 ± 0,18g, distribuídos em um delineamento experimental inteiramente casualizado, com cinco tratamentos e cinco repetições, sendo a unidade experimental constituída por um aquário de 50 L com sete animais. As rações foram formuladas com 32% de proteína bruta e 3000 kcal de energia digestível/kg, sendo as mesmas isoprotéicas, isocalóricas, isofíbricas e isoaminoacídicas para lisina e metionina + cistina. Os valores médios de ganho de peso observados nos tratamentos controle ou com FV e FP como atractantes foram superiores aos dos tratamentos FC ou FO. A conversão alimentar dos animais alimentados com ração contendo FV foi melhor que os tratamentos FC ou FO, porém não diferiu significativamente dos tratamentos controle e FP. O comprimento final médio dos animais do tratamento controle foi superior, quando comparados ao tratamento FC, não diferindo dos demais. O consumo alimentar e a taxa de sobrevivência não diferiram entre os tratamentos. Concluiu-se que não seria necessária a utilização dos alimentos testados, a 5% de inclusão, para estimular o consumo alimentar ou promover o crescimento de alevinos de tilápia do Nilo.The experiment aimed to compare the use of 5% of inclusion of fish meal (FP, poultry by-products meal (FV, meat and bones meal (FO and silkworm meal (FC and a control (soybean meal and corn as atractants on feed intake and performance of Nile tilapia fingerlings. One hundred and sixty eight Nile tilapia fingerlings (Thai strain sexually reversed, with average initial weight of 0.72 ± 0.18 g were

  16. Desempenho e morfometria intestinal de juvenis de tilápia-do-nilo alimentados com dietas suplementadas com L-glutamina e L-glutamato Productive performance and intestinal morphology of Nile tilapia juvenile fed diets with L-glutamine and L-glutamate

    Directory of Open Access Journals (Sweden)

    Lilian Carolina Rosa da Silva

    2010-06-01

    Full Text Available Este estudo foi realizado para avaliar níveis de L-glutamina e L-glutamato em dietas para juvenis de tilápia-do-nilo (0,60 ± 0,1 g. Foi utilizado delineamento inteiramente casualizado com quatro dietas e três repetições e 90 peixes por unidade experimental. Foi utilizada dieta controle, com 29% de proteína digestível e 2.940 kcal/kg de energia digestível, suplementada mistura de L-glutamina e L-glutamato na proporção de 0, 1, 2 e 3% da dieta, durante 85 dias. Não foi observado efeito da L-glutamina e L-glutamato sobre o consumo, a conversão alimentar, a taxa de eficiência protéica, a eficiência de retenção de nitrogênio, o índice hepatossomático, a composição química corporal, a amônia e ureia sanguíneas. O aumento nos níveis de L-glutamina e L-glutamato nas dietas teve aumento linear sobre o ganho de peso e efeito quadrático na altura dos vilos. A adição de L-glutamina e L-glutamato melhora o ganho de peso e a altura das vilosidades intestinais de tilápia-do-nilo.This work was carried out to evaluate levels of L-glutamine and L-glutamate in diets for Nile tilapia juveniles (0.60 ± 0.1 g. A complete randomized experimental design with four diets and three replicates and 90 fish per experimental unit was used. It was used a control diet with 29% of digestible protein and 2,940 kcal/kg of digestible energy supplemented with L-glutamine and L-glutamate at the proportion of 0, 1, 2 and 3% of diet, during 85 days. It was not observed effect of dietary L-glutamine and L-glutamate on feed intake, food conversion, protein efficiency rate, nitrogen retention efficiency, hepatic somatic index, chemical body composition, blood ammonia and urea. It was observed a linear increase on gain weight and a quadratic effet on villus height when levels of L-glutamine and L-glutamate increased. The addition of L-glutamine and L-glutamate increases the weight gain and intestinal villus height of Nile tilapia.

  17. Histologia das brânquias de larvas da tilápia do Nilo, Oreochromis niloticus (L., de origem tailandesa, submetidas a diferentes níveis de vitamina C Histology of branchiae of larvae of Nile tilapia, Oreochromis niloticus (L. from Thailand, with different levels of vitamin C

    Directory of Open Access Journals (Sweden)

    Maria Raquel Marçal Natali

    2001-05-01

    Full Text Available Neste estudo, foi avaliado o efeito da vitamina C sobre a integridade histológica branquial e morfologia das células mucosas, em larvas de tilápia do Nilo, Oreochromis niloticus (Perciformes, cichlidae de origem tailandesa, durante a fase de reversão sexual, em Maringá, Estado do Paraná. Larvas foram submetidas a três diferentes dietas sendo: T1- isenta de vitamina C, T2- 1.000 mg de vitamina C e T3- 2.000 mg por quilo de ração. As alterações histológicas foram classificadas por graus de severidade, numa escala de 1 a 3 unidades de Valor Médio de Alteração (V.M.A., tais como: elevação epitelial, hiperplasia de células dos filamentos, telangectasia e fusão lamelar, que foram significativamente mais freqüentes no T1 em relação ao T2 e T3. As análises morfométricas demonstraram significativo aumento no tamanho médio das células no T1, em relação às do T2 e do T3, (p The effect of vitamin C (ascorbic acid on the histological integrity and the morphology of mucous cells from gill structure of larvae of the Nile tilapia, Oreochromis niloticus (Perciformes, cichlidae, from Thailand, during sex reversion process was evaluated. Assay was performed during 28 days in Maringá PR Brazil. Three diets were given to the larvae: vitamin C-free diet; and two diets with monophosphated vitamin C, or rather, T1 (0; T2 (1,000; T3 (2,000 mg of vitamin C per kilo of diet respectively. Histological changes were classified according to severity levels in a scale ranging from 1 to 3 unities of Mean Assessment Value (MAV. These were epithelial lifting, hyperplasia of filament cells, telangectasy, and lamellar fusion, significantly more frequent in T1 than in T2 and T3. Morphometrical analyses showed an increase in average size of cells in T1 when compared to those of T2 or T3 (p < 0.05. Number of mucous cells showed a higher significant frequency of cells in T1 filaments as a contrast to those of T2 and T3. Results indicate that best inclusion

  18. Mesquite bean and cassava leaf bran in diets for juvenile Nile tilapia kept in water with salinity Farelos da vagem da algaroba e da folha da mandioca em rações para juvenis de tilápia do Nilo mantidos em água salobra

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    João Sérgio Oliveira Carvalho

    2011-12-01

    Full Text Available It was evaluated the inclusion of the mesquite bean (Prosopis juliflora and cassava leaf bran (Manihot esculenta in diets for Nile tilapia (Oreochromis niloticus (2.89±0.43g. 225 fish were used, distributed in 15 tanks (120L in a completely randomized design in a 2x2 factorial design, two sources and three levels of bran (10 and 20%, and a control treatment free of by-products (n=3. After 60 days, it was evaluated the growth performance (daily feed intake, daily weight gain, feed conversion and survival rate and corporal composition of fish. The performance and corporal composition, except the crude protein content, were not affected by the source or level of bran inclusion. The brans evaluated may be applicable in diets of Nile tilapia including up to 20% without decreasing performance.Avaliou-se a inclusão dos farelos da vagem da algaroba (Prosopis juliflora e folha da mandioca (Manihot esculenta em rações para tilápia do Nilo (Oreochromis niloticus (2,89±0,43g. Foram utilizados 225 peixes, distribuídos em 15 tanques (120L, em um delineamento inteiramente casualizado, em esquema fatorial 2x2, duas fontes e dois níveis de farelo (10 e 20%, além de um tratamento controle isento dos coprodutos (n=3. Ao final de 60 dias, foram avaliados o desempenho zootécnico (consumo de ração, ganho de peso, conversão alimentar aparente e taxa de sobrevivência e a composição corporal dos peixes. O desempenho zootécnico e a composição corporal, exceto quanto ao teor de proteína bruta, não foram afetados pela fonte ou nível de inclusão do farelo. Os farelos estudados podem ser utilizados em rações de tilápias do Nilo até 20% de inclusão, sem comprometer o desempenho zootécnico.

  19. Produção, caracterização e avaliação biológica de silagens de resíduos de camarão para tilápia-do-nilo Production, characterization and biological evaluation of shrimp waste silage for Nile tilapia

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    L.U. Gonçalves

    2007-08-01

    Full Text Available Elaboraram-se e caracterizaram-se nutricionalmente dois tipos de silagens fermentadas de resíduos de camarão-sete-barbas (Xiphopenaeus kroyeri, alterando-se as fontes de carboidratos. As silagens foram formuladas com resíduo de camarão, 15% de carboidrato -melaço de cana-de-açúcar (SM ou varredura da farinha láctea (SF-, 10% de iogurte, 0,25% de ácido sórbico e 1% de ácido fórmico. Cada silagem foi caracterizada durante a estocagem, por 120 dias, quanto à composição centesimal, nitrogênio não protéico e todas comparadas por meio do teste de digestibilidade in vivo com juvenis de tilápia-do-nilo. Após o 30° dia de estocagem, observou-se que a SM apresentou maior (P0,05, mas observou-se alta digestibilidade nas dietas (CDA SM= 78,2% e CDA SF= 73,1%. Independente da fonte de carboidrato, as silagens elaboradas com resíduos de camarão-sete-barbas mantiveram-se estáveis durante 120 dias e podem ser utilizadas como ingrediente de rações para a tilápia-do-nilo.Two types of fermented shrimp waste silage (Xiphopenaeus kroyeri were elaborated and characterized, alternating the sources of carbohydrates. The silages were elaborated with shrimp waste, 15% of carbohydrate - sugar cane molasses (SM or "Farine Lactée" (SF -, 10% of yogurt, 0.25% of sorbic acid, and 1% of formic acid. Each silage was characterized during storage for 120 days on proximate composition and non protein nitrogen, besides nutritionally compared by digestibility trials to Nile tilapia juveniles. After the 30th storage day, it was observed that SM presented higher ashes content (SM= 34.97g.100g-1 and SF= 30.92g.100g-1 and lower dry matter content (SM= 20.02g.100g-1, SF= 21.11g.100g-1. The apparent digestibility (ADC and digestible protein coefficients did not vary between trials (P>0.05, but higher digestibility in the diets (ADC SM= 78.2%, ADC SF= 73.1% was observed. No matter which carbohydrate source used, silage made from shrimp waste remained stable for

  20. Mananoligossacarídeo em dietas para juvenis de tilápias do Nilo - doi: 10.4025/actascianimsci.v32i2.7724 Mannanoligosaccharides in diets for Nile tilapia, juveniles - doi: 10.4025/actascianimsci.v32i2.7724

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    Mirian Cristina Gualdezi

    2010-07-01

    Full Text Available O presente estudo foi realizado com o objetivo de avaliar a inclusão de mananoligossacarídeo (MOS em dietas para juvenis de tilápias do Nilo. Foram utilizados 224 peixes (25 g ±1,0 g, em um período de 53 dias e os peixes foram distribuídos em um delineamento em blocos ao acaso, sendo considerado como bloco cada tanque de 1.000 L com 16 gaiolas de 0,12 m3 cada. Foi utilizada dieta-controle com 28,5% de proteína bruta e 2.855 kcal de energia digestível kg-1 e adicionado MOS nas proporções de 0, 1, 2 e 3%. Não foi observado efeito (p > 0,05 dos níveis de inclusão de MOS sobre o consumo, índice hepatossomático, sobrevivência, umidade, cinzas corporal, coeficiente de digestibilidade aparente da máteria seca, energia bruta, proteína bruta, extrato etéreo e disponibilidade das cinzas, densidade de vilos intestinais e número de células caliciformes por vilo. Os melhores resultados (p This study was carried out to assess the inclusion of mannanoligosaccharides (MOS in diets for Nile tilapia juveniles. Two-hundred and twenty fish with an average initial weight of approximately 25 ± 1.0 g were used, during 53 days. Fish were distributed in a randomized block design. Each 1,000 L tank with four cages (0.12 m3 each, was considered as a block; fish in each cage received a different dietary treatment. A control diet with 28.5% of crude protein and 2,855 kcal of digestible energy kg-1 was used and dietary MOS was included at 0, 1, 2 and 3%. No effects of MOS on feed intake, hepatosomatic index, survival, moisture, body ash, apparent digestibility coefficients of dry matter, gross energy, crude protein, ether extract and ash availability, intestinal villi density and number of goblet cells per villus were observed. The best values of feed-to-gain ratio, protein efficiency ratio, body composition and villi height were observed in fish fed with dietary MOS. It was concluded that 1% of dietary MOS is adequate for Nile tilapia juveniles.

  1. Desempenho da tilápia-do-Nilo arraçoada com dietas contendo farinha de sangue bovino atomizado ou convencional - doi: 10.4025/actascianimsci.v33i3.10736 Performance of nile tilapia fed with spray-dried or vat-dries bovine blood meal - doi: 10.4025/actascianimsci.v33i3.10736

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    Gustavo do Valle Polycarpo

    2011-06-01

    Full Text Available Foi avaliado o desempenho e os índices de rendimento da tilápia-do-Nilo (Oreochromis niloticus alimentada com níveis crescentes de farinha de sangue atomizado (FSA ou de farinha de sangue convencional (FSC em dietas formuladas com base em aminoácidos digestíveis. Foram utilizados 252 alevinos, distribuídos num delineamento inteiramente casualizado, em esquema fatorial (2 x 4 + 1, duas classes de farinha de sangue com quatro níveis de inclusão de cada farinha na dieta, e uma dieta-controle, com quatro repetições. Os tratamentos consistiram em uma dieta-controle à base de farelo de soja, contendo 34% de proteína digestível (PD e 3.200 kcal de energia digestível kg-1 (ED, mais quatro rações formuladas com FSA e quatro rações com FSC, com inclusões de 5, 10, 15 e 20% de cada farinha na ração, mantendo-se os níveis de PD, ED, fósforo, cálcio, lisina, metionina, treonina e triptofano idênticos aos da dieta-controle. Concluiu-se que é possível utilizar até 15% da FSC em rações para tilápia-do-Nilo na fase de 5 a 150 g de peso vivo.The study evaluated the performance and carcass composition index of Nile tilapia (Oreochromis niloticus fed with diets containing increasing levels of spray-dried blood meal (SDBM and vat-dried blood meal (VDBM and formulated based on digestible amino acids. Two hundred and fifty-two fingerlings were distributed in a completely randomized design, in a (2 x 4 + 1 factorial model, two types of blood meal with four levels of each blood meal in the diet, and a control diet (without blood meal, with four replications. The treatments consisted of soybean meal-based control diet, with 34% digestible protein (DP and 3,200 kcal of digestible energy kg-1 (DE, plus four diets formulated with SDBM and four diets with VDBM, containing 5, 10, 15 and 20% of each meal in feed, maintaining identical DP, DE, phosphorus, calcium, lysine, methionine, threonine and tryptophan levels as those of the control diet

  2. Farelo de canola para juvenis de tilápia do Nilo (Oreochromis niloticus, linhagem Chitralada - DOI: 10.4025/actascianimsci.v26i1.1896 Canola meal for juvenile Nile tilapia, Chitralada strain - DOI: 10.4025/actascianimsci.v26i1.1896

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    Thiago Romano Fernandes

    2004-04-01

    Full Text Available Este estudo teve como objetivo avaliar os efeitos da inclusão de diferentes níveis de farelo de canola em rações, sobre o desempenho e composição de carcaça de juvenis de tilápia do Nilo (Oreochromis niloticus L., linhagem Chitralada. Foram utilizadas 15 caixas de polipropileno com capacidade para 310L, com dez peixes por unidade. Os peixes foram alimentados à saciação com cinco rações isoprotéicas (28% e isocalóricas (2900 Kcal ED/Kg, duas vezes ao dia, durante seis meses. O farelo de canola foi utilizado em quatro níveis (TT=0%, T1=8%, T2=16%, T3=24%, e T4=32%/dieta, em um delineamento inteiramente casualizado com cinco tratamentos e três repetições. Os valores obtidos foram submetidos à análise de variância (ANOVA e as médias comparadas pelo teste de Tukey (p0,1 sobre a composição corporal dos peixes, sendo que os níveis de 16% e 24% de farelo de canola proporcionaram os melhores ganhos de peso. Conclui-se que a utilização do farelo de canola é viável quando incluído em até 24% na ração para a tilápia do Nilo, linhagem Chitralada.This work evaluated the inclusion of several levels of canola meal in ration used in the development and carcass compositions of juvenile Nile tilapia (Oreochromis niloticus L., Chitralada strain. Were used 15 polypropylene boxes, with 310 liters (10 fish each. The fish were fed with five isonitrogenous (28% and isocaloric ration (2900 Kcal EM/kg, twice a day for six months. The canola meal was used in four levels (TT = 0%, T1 = 8%, T2 = 16%, T3 = 24% and T4 = 32% / diet, in a completely randomized design, with 5 treatments and three repetitions each. The data obtained were submitted to variance analysis (ANOVA and the averages compared by the Tukey test (p0,1 on fishes body composition, however had best body weight gain with canola meal on levels 16% and 24%. These values seem to show that for the Nile Tilapia, Chilatrada strain, the use of canola meal is viable when included in up

  3. Processing yield of Nile tilapia (Oreochromis niloticus: head cut types and two weight classes Rendimento do processamento da tilápia-do-nilo (Oreochromis niloticus: tipos de corte da cabeça em duas categorias de peso

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    Maria Luiza Rodrigues de Souza

    2000-05-01

    Full Text Available The aim of this study was to evaluate the best type of head cut of Nile tilapia (Oreochromis niloticus resulting in better fillet processing yields. The experiment was carried out at the Pisciculture Station of UEM/Codapar, Maringá, Paraná, Brazil. One hundred and twenty specimens were slaughtered, head cut, eviscerated, and had their fin, skin and fillet removed. The fillet processing was undertaken by a single person. Plotting was completely randomized by a 2x3 factorial scheme. Treatments consisted of two weight categories ( W1=250-400g and W2=401-550g and three types of head cut (C1=oblique, OB; C2=Contour, CO, and C3=strainght, ST, with 20 replicates. Each fish was considered an experimental unit. Mean values of yield were expressed in relation to fish body weight. There was an influence of head cut types and weight categories on the dressed out and fillet yield. The yields in W2 (OB=50.42%, 35.27%; CO=50.70%, 35.18% and ST=48.50%, 33.82% were higher (p O objetivo do presente estudo foi avaliar o melhor tipo de corte de cabeça para decapitação da tilápia-do-nilo (Oreochromis niloticus, que resulte em melhores rendimentos de filetagem. O experimento foi conduzido na Estação de Piscicultura da UEM/Codapar, Maringá, PR. Foram abatidos 120 exemplares cortadas as cabeças, eviscerados, removidas as nadadeiras, pele e filés. O processo de filetagem foi realizado por uma única pessoa. O delineamento foi inteiramente casualizado, em esquema fatorial 2x3. Os tratamentos foram: duas categorias de peso (P1= 250-400 g e P2= 401-550 g e três tipos de corte de cabeça (C1=oblíquo, OB; C2=contornado, CO e C3=reto, RE, com 20 repetições. Cada peixe foi considerado a unidade experimental. Os valores médios de rendimento foram expressos em relação ao peso corporal do peixe. Houve influência do tipo de corte e categoria de peso sobre o rendimento do tronco limpo e filé. Os rendimentos em P2 (OB=50,42%, 35,27%; CO=50,70%, 35,18% e RE=48

  4. Aproveitamento de peles de tilápia-do-nilo congeladas e salgadas para extração de gelatina em processo batelada Utilization of frozen and salted Nile tilapia skin for batch-processed gelatin extraction

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    Adriana Cristina Bordignon

    2012-03-01

    Full Text Available Objetivou-se caracterizar peles de tilápia-do-nilo, conservadas por congelamento e salga a seco, visando à extração de gelatina em processo batelada. Após a filetagem, as peles foram descarnadas e distribuídas em dois lotes. Um dos lotes foi congelado a -18 ºC por sete dias e o outro foi salgado e mantido a 25 ºC por sete dias. As peles foram lavadas, pesadas e pré-tratadas em solução de H2SO4 a10N (pH 3,0, na proporção de 1:6 (pele:água por uma hora a 24 ºC. Extraiu-se a gelatina em banho-maria a 50 ºC por uma hora e retirou-se uma amostra para análise do perfil molecular. O restante foi congelado a -18 ºC. Foram realizadas análises físico-químicas das peles e das gelatinas líquidas, do perfil molecular com as gelatinas e análises microbiológicas das peles. As peles congeladas e salgadas apresentaram, respectivamente, 78,13 e 76,46% de umidade; 18,16 e 19,59% de proteína bruta; 2,26 e 1,90% de extrato etéreo e 1,44 e 2,06% de cinzas. Nas gelatinas líquidas extraídas das peles congeladas e salgadas, a umidade foi de 97,68 e 96,08%, o conteúdo de proteína bruta de 3,18 e 4,12%, de extrato etéreo 0,29 e 0,18% e de cinzas de 2,31 e 3,03%, respectivamente. Os valores da força de gel e viscosidade foram maiores para a gelatina de peles salgadas (200 g e 19,02mPas em comparação à gelatina de peles conservadas pelo congelamento (12,7 g e 9,16mPas. O perfil molecular foi menor na gelatina extraída a partir de peles congeladas, portanto houve perda de β e γ-componentes, que indica grande degradação do colágeno decorrente do método de conservação.The objective was to characterize Nile tilapia skins, freeze- and dry salt dry-preserved to extract gelatins by batch processing. After filleting, the skins were separated from the meat and distributed into two lots: In one, skins were frozen for 7 days (-18 ºC; and in the other, skins were salted for seven days (25 ºC. The skins were rinsed, weighed and pretreated in

  5. Efeito da cor do ambiente sobre o estresse social em tilápias do Nilo (Oreochromis niloticus Effect of background color on the social stress of Nile tilapia (Oreochromis niloticus

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    Giovana Krempel Fonseca Merighe

    2004-08-01

    ão recomendadas à manutenção da espécie, por amenizarem as interações agonísticas e o estresse, enquanto a marrom e azul devem ser evitadas por estimularem estas respostas.It was studied the behavior and physiologic answers of juvenile of Nile tilapia, Oreochromis niloticus, submitted the different backgrounds colors and social situations. The animals were maintained isolated in fishbowls covered with colored paper-card, composing five treatments (black, green, brown, blue and white. Through weekly filmings and in different and alternate stages (isolation and presence of a mirror, it enrolled the following parameters: distribution in the column of water, coloration, motility, agonistic behaviors, position of the dorsal fin and posture. For quantification of the glucose, triglycerides, total proteins and cortisol levels, were collected samples of blood after each filming. The obtained averages were analyzed statistically through the no-parametric Kruskal-Wallis method. The fish maintained in the black and green background presented low frequencies of agonistic behaviors, while those maintained in the white background, high frequencies, even so with low numbers of the alert pattern and not altering its motility. Animals submitted to the brown and blue colors presented the highest frequencies of agonistic behaviors, and larger motility. The fish stayed in all the treatments with the clear coloration, occupying, with larger frequency, the bottom of the column of water. Significant differences were not observed for the glucose, triglycerides and total proteins concentrations among the treatments, even so it was obtained a high level of cortisol for the animals maintained in the blue and brown backgrounds when submitted to the reflection of the own image in mirror. These results showed that there is influence of the background color on the social stress, in particular in the agonistic interactions among individuals of the same specie and in the concentration of the hormone

  6. Inhibition of West Nile virus multiplication in cell culture by anti-parkinsonian drugs

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    Ana Belen Blazquez

    2016-03-01

    Full Text Available West Nile virus (WNV is a mosquito-borne flavivirus maintained in a transmission cycle between mosquitoes and birds, but it can also infect other vertebrates, including humans, in which it can cause neuroinvasive diseases. To date, no licensed vaccine or therapy for human use against this pathogen is yet available. A recent approach to search for new antiviral agent candidates is the assessment of long-used drugs commonly administered by clinicians to treat human disorders in drug antiviral development. In this regard, as patients with West Nile encephalitis frequently develop symptoms and features of parkinsonism, and cellular factors altered in parkinsonism, such as alpha-synuclein, have been shown to play a role on WNV infection, we have assessed the effect of four drugs (L-dopa, Selegiline, Isatin and Amantadine, that are used as therapy for Parkinson´s disease in the inhibition of WNV multiplication. L-dopa, Isatin, and Amantadine treatments significantly reduced the production of infectious virus in all cell types tested, but only Amantadine reduced viral RNA levels. These results point to antiparkinsonian drugs as possible therapeutic candidates for the development of antiviral strategies against WNV infection.

  7. Parasite treatment reduced Flavobacterium columnare infection in tilapia

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    Bacterium Flavobacterium columnare and parasite Trichodina are common pathogens of cultured fish. The authors conducted a study to evaluate whether treatment of Trichodina parasitized tilapia with formalin would improve fish survival and reduce F. columnare infection in fish. Tilapia parasitized by...

  8. Serotype distribution and antimicrobial susceptibilities of Streptococcus agalactiae isolated from infected cultured tilapia (Oreochromis niloticus) in Thailand: Nine-year perspective.

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    Dangwetngam, Machalin; Suanyuk, Naraid; Kong, Fanrong; Phromkunthong, Wutiporn

    2016-03-01

    Streptococcus agalactiae (group B Streptococcus, GBS) infection remains a major problem associated with high mortality of cultured tilapia worldwide. The present study reports the serotype distribution and antimicrobial susceptibilities of GBS isolated from infected tilapia cultured in Thailand. One hundred and forty-four GBS isolates were identified by biochemical, serological and molecular analyses. Of these 144 GBS isolates, 126 were serotype Ia and 18 were serotype III. Antimicrobial susceptibilities of the 144 GBS isolates were determined by the disc diffusion method. Most GBS isolates were susceptible to lincomycin, norfloxacin, oxytetracycline, ampicillin, erythromycin and chloramphenicol, but resistant to oxolinic acid, gentamicin, sulfamethoxazole and trimethoprim. However, 17 isolates displayed an oxytetracycline-resistant phenotype and harboured the tet(M) gene. The broth microdilution method was used to determine the minimal inhibitory concentrations (MICs) of 17 oxytetracycline-resistant GBS isolates, and then minimal bactericidal concentrations (MBCs) of these isolates were evaluated. Oxytetracyline-resistant isolates were found to be susceptible to ampicillin, lincomycin, norfloxacin, erythromycin and chloramphenicol, with the MIC and MBC ranging from ≤ 0.125 to 0.5 μg ml- 1 and ≤ 0.125 to 2 μg ml- 1, respectively. Moreover, all 17 oxytetracycline-resistant isolates demonstrated resistance to trimethoprim, oxolinic acid, gentamicin, sulfamethoxazole and oxytetracycline, with the MIC and MBC ranging from 16 to ≥ 128 μg ml- 1 and ≥ 128 μg ml- 1, respectively. These findings are useful information for antibiotic usage in fish aquaculture.

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

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    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.

  10. Digestibilidade e desempenho de alevinos de tilápia do nilo (Oreochromis Niloticus alimentados com dietas contendo diferentes níveis de silagem ácida de pescado Digestibility and performance of nile tilapia (Oreochromis Niloticus fed diets with different levels of acid silage

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    Marinez Moraes de Oliveira

    2006-12-01

    Full Text Available Os experimentos foram conduzidos para avaliar os coeficientes de digestibilidade aparente dos nutrientes e da energia bruta da silagem ácida de resíduos da filetagem de tilápia do Nilo (Oreochromis niloticus para alevinos de tilápia nilótica e o desempenho dos alevinos recebendo níveis crescentes (0, 10, 20, 30, 40 % da silagem ácida em substituição à farinha de peixe na ração. Na digestibilidade foram utilizados 200 alevinos revertidos sexualmente, com peso médio de 2,0 g e acondicionados em aquários de 40 litros. A coleta de fezes foi feita durante 7 dias seguintes e a determinação dos coeficientes de digestibilidade aparente e energia metabolizável aparente foi feita por metodologia indireta, tendo sido utilizado 1% de Cr2O3 como indicador incorporado à ração. No desempenho, foram utilizados 2000 alevinos revertidos sexualmente com peso médio de 0,45 g, acondicionados em "hapas" de 1m², dispostos em um viveiro escavado. As variáveis analisadas foram: ganho de peso final (GPF, consumo de ração total (CRT, conversão alimentar aparente (CAA, acréscimo em altura (AA e em comprimento (AC. O delineamento utilizado foi o inteiramente casualizado, com 5 tratamentos e 4 repetições. Os valores de digestibilidade encontrados foram: coeficiente de digestibilidade aparente da matéria seca, 95,49%; coeficiente de digestibilidade aparente da proteína bruta, 96,66%; coeficiente de digestibilidade aparente do extrato etéreo, 97,18%; coeficiente de digestibilidade aparente da energia bruta, 95,44%, e energia digestível aparente 2.880,02 kcal/kg. Não houve diferença significativa (P> 0,05 para ganho de peso final, consumo de ração total, conversão e acréscimo em altura. Observou-se aumento linear (PThe experiments were carried out in order to evaluate the apparent digestibility coefficients of the nutrients and gross energy of acid silage of filetage residues from Nile tilapia (Oreochromis niloticus. This silage was given

  11. Qualidade do sêmen em tilápia do Nilo (Oreochromis niloticus, alimentadas com dietas contendo diferentes níveis de vitamina C - doi: 10.4025/actascianimsci.v32i3.7836 Semen quality in Nile tilapia (Oreochromis niloticus, fed with diets containing different vitamin C levels - doi: 10.4025/actascianimsci.v32i3.7836

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    Gentil Vanini de Moraes

    2010-09-01

    Full Text Available A vitamina C atua na proteção de danos celulares provocados pelos radicais livres, sendo a suplementação considerada essencial para a maioria das espécies de peixes, uma vez que não a sintetizam em função da ausência da enzima L-gulonolactona oxidase. Assim, avaliou-se o efeito da suplementação de 0, 75, 150 e 225 mg de vitamina C kg-1 de ração na qualidade do sêmen em tilápias do Nilo (Oreochromis niloticus. Os parâmetros quali-quantitativos do sêmen não foram influenciados pela suplementação de vitamina C, exceto a motilidade progressiva que aumentou linearmente com adição de vitamina C. Conclui-se que os reprodutores de tilápias do Nilo devem ser suplementados com 225 mg de vitamina C kg-1 de ração.Vitamin C acts as cellular protection from damage by free radicals, and vitamin C supplementation is considered essential for most fish species, as they do not synthesize it due to the absence of enzyme L-gulonolactone oxidase. Thus, the effect of supplementation with 0, 75, 150 and 225 mg of vitamin C kg-1 of ration was evaluated in the semen quality in Nile tilapia (Oreochromis niloticus. Seminal parameters were not influenced by vitamin C supplementation except progressive motility, which increased linearly with the addition of vitamin C. It was concluded that Nile tilapia reproducers should be supplemented with 225 mg vitamin C kg-1 ration.

  12. Grau de moagem dos alimentos em rações para a tilápia do Nilo (Oreochromis niloticus durante o período de reversão sexual - DOI: 10.4025/actascianimsci.v27i1.1245 Milling degree of feed in ration for Nile tilapia (Oreochromis niloticus larvae during sexual reversion phase - DOI: 10.4025/actascianimsci.v27i1.1245

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    Robie Allan Bombardelli

    2005-03-01

    Full Text Available O experimento avaliou o efeito de diferentes graus de moagem dos alimentos sobre o desempenho de larvas de tilápia do Nilo no período de reversão sexual. O delineamento experimental foi inteiramente casualizado com 4 tratamentos e 6 repetições. Os tratamentos foram os graus de moagem dos alimentos em peneira de malhas de 0,25; 0,50; 0,70 e 1,00 mm. Utilizou-se uma ração de modo a atender às necessidades nutricionais da espécie. Foram avaliados peso (PFM, comprimento (CFM, ganho de peso diário (GPD, fator de condição (FC e sobrevivência (S. Os dados foram submetidos à ANOVA e, à análise de regressão em caso de evidência de diferença significativa (P = 0,05. Apenas PFM, GPD e FC apresentaram efeito dos tratamentos, mostrando efeito quadrático (P This work evaluated the effect of different milling degree of feeds on Nile tilapia performance during sex reversal period. A completely randomized design with four treatments and six replicates was utilized. The treatments were the milling degree of feed by 0.25, 0.50, 0.70, and 1.00 mm screen. The diets used fulfilled larvae necessity. Data of weight (W, length (L, daily gain weight (DGW, factor condition (FC and survival (S were evaluated. Data were submitted to ANOVA and regression analysis in case of significant difference were detected (P = 0.05. Only W, DGW and FC presented significant difference between treatments, showing a quadratic effect (P < 0.05 and better results to 0.60, 0.60 and 0.63 mm of feed milling degree, respectively. Diet with milling degree of 0.60 mm screen was recommended to Nile tilapia reversion phase

  13. Evaluation of production performance and profitability of hybrid red tilapia and genetically improved farmed tilapia (GIFT strains in the carbon/nitrogen controlled periphyton-based (C/N- CP on-farm prawn culture system in Bangladesh

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    M. Rezoanul Haque

    2016-11-01

    Full Text Available Performance of hybrid red tilapia (Mutant, Oreochromis niloticus × Oreochromis mossambicus and GIFT tilapia strain (Oreochromis niloticus in C/N-CP prawn (Macrobrachium rosenbergii farming system was evaluated at the farmers' pond at Bailor union under Trishal upazilla of Mymensingh district, Bangladesh. The on-farm trial had two treatments: TR and TG (named according to the tilapia strains with three replications. Six rectangular ponds of varying sizes (400–880 m2 were used for this experiment. Hybrid red and GIFT tilapia stains were stocked with prawn at the stocking densities of 1 tilapia fingerlings (either red or GIFT strain and 3 prawn juveniles m-2 in both treatments. Bamboo side shoot were posted vertically as periphyton substrate. This resulted in an additional substrate surface area of 1067 m2 for periphyton development equaling 147% of the pond surface area. Considering the body weight of freshwater prawn only, feeding rates were 10% of body weight at the beginning of the study (up to 30 days, and feeding application was gradually reduced to 3% in the last month assuming 80% survival. The abundance of total benthos and periphyton as well as total periphytic biomass were significantly higher (P < 0.05 in TR than TG treatment and they were also differed significantly (P < 0.05 among different months with a decreasing trends (exception to some extent over the experimental period. The individual harvesting weight, individual weight gain, specific growth rate, Food Conversion Ratio (FCR, survival (%, gross and net yields of prawn were similar in two treatments. In contrast, the GIFT tilapia strain showed a higher (P < 0.05 individual harvesting weight, individual weight gain, specific growth rate ((SGR, % bw d-1, survival, gross and net yields (1935 and 1825 kg ha-1, respectively combined gross and net yields (2952 and 2784 kg ha-1, respectively, and economic return (3755 US$ with BCR 0.82 than the hybrid Red tilapia.

  14. Polyculture of fresh water shrimp Macrobrachium amazonicum (Heller, 1862 wifh Nile tilapia (Oreochromis niloticus feeding with ration pelleted and mashed / Policultivo do camarão de água doce Macrobrachium amazonicum (Heller, 1862 com a Tilápia do Nilo (Oreochromis niloticus alimentadas com rações peletizada e farelada

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    Leandro Bohnenberger

    2009-07-01

    Full Text Available The objective of this work was to evaluate the influence of fresh water shrimp Macrobrachium amazonicum (Heller, 1862 in performance of Nile tilapia (Oreochromis niloticus cultivated in polyculture system and feeding with ration pelleted and mashed. The work was realized in Centro de Pesquisa em Aqüicultura Ambiental-CPAA/IAP – Toledo/PR during 37 days. Were utilized like experimental unit 16 ponds excavated, covered with concrete but with bottom of soil with dimension the 4 x 3 m and useful volume the 3,5 m3. Were utilized 30 tilapias e 150 shrimps for experimental unit distributed at an entirely randomized design with 4 treatments and 4 replications, where TF: tilapia feeding with ration mashed; TCF: tilapia and shrimp feeding with ration mashed; TP: tilapia feeding with ration pelleted; TCP: tilapia and shrimp feeding with ration pelleted. The density used were the 2,6 fishes/m2 with medium initial weight the 5,58 ± 0,10 g and initial length the 5,56 cm, and the density of shrimp was the 13 shrimps/m2 with initial length the 1,04 cm. The temperature was gauged daily, while the variables dissolved oxygen, pH and electrical conductivity, weekly. The quantity of ration supplied was the 10% of total biomass of fishes, with feed frequency the 4 times a day, being corrected weekly in function of the biometry. During the experimental period the medium values of temperature, dissolved oxygen, pH and electrical conductivity of the ponds water were 23,42 ± 0,83ºC, 5,32 ± 0,52 mg/L, 7,02 ± 0,39, e 100,96 ± 1,81 µS/ cm respectively. Won´t registering any influence of shrimp during the cultivation and the ration pelleted provide the better conversion alimentary and performance of tilapias.O objetivo deste trabalho foi avaliar a influência do camarão de água doce Macrobrachium amazonicum (Heller, 1862 no desempenho da Tilápia do Nilo (Oreochromis niloticus cultivada no sistema de policultivo e alimentada com rações peletizadas e fareladas

  15. The influence of ration size on energetics and nitrogen retention in tilapia (Oreochromis niloticus)

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    Skov, Peter Vilhelm; Duodu, Collins Prah; Adjei-Boateng, Daniel

    2017-01-01

    of dietary nutrient intake, the effects of meal size on growth and metabolism were examined in triplicate groups of adult Nile tilapia (Oreochromis niloticus) receiving daily rations corresponding to 1, 2, 3, or 4% of their biomass. While biomass gain and specific growth rates were positively correlated...

  16. Evaluation of the technological quality presented for a canned Nile tilapia (Oreochromis niloticusAvaliação da qualidade tecnológica apresentada por tilápia do Nilo (Oreochromis niloticus enlatada

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    Cleonice Sarmento

    2012-05-01

    Full Text Available The fish is quite sensitive to the deterioration due to the high activity of water and, especially to a near pH of the neutrality. The application of the heat needs a rigorous control of time and temperature. The objective of this work developed meat of tilapia canned in vegetable edible oil, for the use from the nonstandard raw material, in order to offer a product with high collected value. The meat of tilapia were taken to the daily pay-cooking in fluent steam for approximately 50 minutes, when the oil of covering was next added, when re-drove and been subdued to two thermal treatments respectively of 15 and 30 minutes in autoclave 121°C. After that the microbiological analyses were carried out, chemical-physically and sensory. The microbiological evaluation showed that the products were presenting satisfactory conformable quality to legislation. The pickles of tilapia presented next composition centesimal: moisture 48.4 %; ashes 3.1 %; protein 12.2 %; lipids 32.7 %; chloride 0.8 %. The sensory analysis showed what, did not exist significant difference at the level of 5 % in the different treatments. The test of commercial sterility was carried out also, where two thermal treatments were adapted to maintain the quality of the pickle of tilapia canned. It was ended that, the pickles of tilapia, they presented quality compatible with similar products, confirming the viability of production of this product. O objetivo deste trabalho foi avaliar microbiologicamente, físico-quimicamente e sensorialmente uma conserva de tilápia enlatada em óleo vegetal comestível, aproveitando matéria-prima fora do padrão, a fim de oferecer um produto com alto valor agregado. As conservas de tilápia foram levadas a pré-cozimento em vapor fluente por aproximadamente 50 minutos, em seguida adicionado o óleo de cobertura, recravadas e submetidas a dois tratamentos térmicos respectivamente de 15 e 30 minutos em autoclave a 121°C. Após isso foram realizadas

  17. Interaction between afternoon aeration and tilapia stocking density

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    Francisco Roberto dos Santos Lima

    2016-01-01

    Full Text Available 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 aeration was carried out from 12.00 a.m. up to 18.00 p.m. from the 3rd week until the end of the experiment. Except for the 16-fish tanks, the lowest concentrations of total ammonia nitrogen were found in the tanks with higher density of fish provided with afternoon aeration. Nitrite concentrations were lower in the 8-fish aerated tanks. In intensive system, the afternoon aeration of the fish culture water is an efficient management of water quality to remove gaseous ammonia and nitrite from water, but it is not appropriate to remove hydrogen sulfide from water.

  18. Silagem ácida do resíduo do camarão Litopenaeus vannamei em rações para tilápia do Nilo - DOI: 10.4025/actascianimsci.v31i2.5097 Acid silage of shrimp Litopenaeus vannamei waste in Nile tilapia diets - DOI: 10.4025/actascianimsci.v31i2.5097

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    Carlos Alberto da Silva Ledo

    2009-08-01

    Full Text Available Rações isoproteicas (30% PD e isoenergéticas (3.200 kcal kg-1 foram formuladas, utilizando-se a silagem ácida de resíduo de camarão branco como fonte proteica alternativa em cinco diferentes níveis de inclusão 0, 4, 8, 12 e 16%. Foram utilizados 200 peixes com peso médio de 7,2 ± 0,5 g, distribuídos aleatoriamente em 20 tanques de 100 L cada, numa densidade de dez peixes tanque-1, em sistema de recirculação de água fechado. Foi utilizado um delineamento inteiramente casualizado com cinco tratamentos e quatro repetições. Foram avaliados parâmetros de desempenho produtivo e composição centesimal do tecido muscular em alevinos de tilápia, alimentados três vezes por dia, até a saciedade aparente, durante 60 dias. Foram observados efeito quadrático (p L. vannamei proporciona melhores resultados de desempenho, sem alterações prejudiciais no tecido muscular, quando utilizada em 2,75% de inclusão em rações para alevinos de tilápia do NiloIsoproteic (30% DP and isoenergetic (3,200 kcal kg-1 diets were formulated using acid silage of shrimp waste as alternative protein source at five levels (0, 4, 8, 12 and 16%. Two hundred fish (7.2 ± 0.5 g were randomly distributed in 20 tanks of 100 L at a density of 10 fish tank-1 in a closed recirculation water system. The experiment was accomplished in a completely randomized design with 5 treatments and 4 replicates. Growth performance and proximal composition parameters of the muscular tissue were evaluated to tilapia fed three times a day to satiation during sixty days. Quadratic effect (p L. vannamei waste provide better growth performance, without losses in proximate composition of the muscular tissue, with 2.75% of inclusion in fingerling Nile tilapia diets

  19. The Effect of Substituting Fishmeal Diets with Varying Quantities of Ensiled Parboiled Beniseed (Sesamum indicum and Raw African Locust Bean (Parkia biglobosa on the Growth Responses and Food Utilization of the Nile Tilapia Oreochromis niloticus

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    S.A. Binga

    2008-01-01

    Full Text Available A mixture of ensiled parboiled beniseed (Sesamum indicum and raw African locust bean (Parkia biglobosa replaced fishmeal in the diet of Oreochromis niloticus at 0, 30, 70 and 100% test materials inclusion levels. Each dietary treatment was randomly duplicated in tanks stocked with twenty fingerlings (2.71 0.003 g and fed three times (08:00, 14:00 and 18:00 h to satiation for 56 days. The result revealed best live weight gain and feed utilization in the fish fed diet D4 followed by diet D1 and D3 with the least value recorded in fish fed diet D2 level. Generally, there was significant increase (p4 and control. The result supports the suggestion that tilapia can be fed with mixture of ensiled parboiled beniseed and raw African locust bean which is hoped will reduce tremendously the over dependence on fishmeal protein and human utilization of the very scarce fish meal.

  20. Fitase na alimentação da tilápia do Nilo (Oreochromis niloticus, durante o período de reversão de sexo - DOI: 10.4025/actascianimsci.v26i3.1778 Phytase as feeding for Nile tilapia (Oreochromis niloticus, during sex reversion period - DOI: 10.4025/actascianimsci.v26i3.1778

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    Lilian Carolina Rosa Silva

    2004-04-01

    Full Text Available Este trabalho foi realizado para avaliar a influência de níveis de fitase sobre o desempenho da tilápia do Nilo (Oreochromis niloticus no período de reversão de sexo. Foram utilizadas 1000 larvas de tilápia do Nilo com peso inicial 0,02 ± 0,002g, alimentadas com rações contendo 0; 500; 1000; 2000 e 4000 unidades de fitase (UF/kg, durante 31 dias. A ração referência continha 3143 kcal de energia digestível/kg, 30% de proteína bruta e 0,85 e 0,35% de fósforo (P total e disponível, respectivamente. Não foram observados efeitos (P>0,05 dos valores de inclusão de fitase sobre o ganho de peso e taxa de sobrevivência. O aumento nos níveis de fitase nas rações elevou linearmente (PThis work was carried out to examine the influence of dietary levels of phytase on Nile tilapia (Oreochromis niloticus performance during the sex reversion period. Were used 1,000 fries of Nile tilápia with initial weight 0.02 ± 0.002g, fed with diets containing 0; 500; 1000; 2000 and 4000 phytase units (PU/kg of diet 31 days. The reference diet provided 3,143 kcal of digestible energy/kg, 30% of crude protein and 0,85 and 0,35% of total and disponible phosphorus (P, respectively. No effects (P>0.05 were observed of phytase inclusion on weight gain and survival rate. Dietary phytase levels increase linearly (P<0.05 the calcium retention in the carcass. There was observed quadratic effect (P<0.05 of dietary phytase supplementation on P retention in the carcass, estimated the values of 1,990 PU/kg for the highest value for this variable. The results of this work indicate that a dietary level of 1,990 of PU provide maximal P retention in the carcass of Nile tilapia, during sex reversal period.

  1. Levedura íntegra e derivados do seu processamento em rações para tilápia do Nilo: aspectos hematológicos e histológicos - DOI: 10.4025/actascibiolsci.v28i4.161 Whole yeast and yeast derivatives in Nile tilapia diets: hematological and histological aspects- DOI: 10.4025/actascibiolsci.161

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    Luiz Edivaldo Pezzato

    2007-11-01

    Full Text Available Os efeitos da inclusão de levedura íntegra, levedura autolisada e parede celular para juvenis da tilápia do Nilo sobre parâmetros hematológicos e perímetro das vilosidades intestinais foram avaliados após 80 dias de experimento. Foram utilizadas rações práticas isoprotéicas (32,0% PD e isoenergéticas (3.200 kcal ED kg-1 de ração suplementadas com três níveis de levedura íntegra ou autolisada (1,0; 2,0 e 3,0% e três níveis de parede celular (0,1; 0,2 e 0,3%, além de uma ração controle, isenta destes microingredientes. Foram avaliados a contagem de eritrócitos, taxa de hemoglobina, proteína plasmática total, porcentagem de hematócrito, volume globular médio, concentração de hemoglobina globular média e o perímetro das vilosidades intestinais. Constatou-se que as variações nos parâmetros hematológicos dos animais alimentados com levedura íntegra, levedura autolisada e parede celular estão dentro da faixa de normalidade para a espécie. Houve influência significativa (pThe effects of inclusion of whole yeast, autolyzed yeast and yeast cell wall on hematological parameters and gut villus perimeter were evaluated in juvenile Nile tilapia, after 80 experimental days. Isoproteic (32.0% DP and isoenergetic (3200 kcal DE kg-1 practical diets were supplemented with three levels of whole yeast or autolyzed yeast (1.0, 2.0 and 3.0% and three levels of yeast cell wall (0.1, 0.2 and 0.3%, plus a control diet (with no test microingredients. Red blood cell count, hemoglobin concentration, total plasmatic protein, hematocrit percentage, mean corpuscular volume, mean corpuscular hemoglobin concentration and gut villus perimeter were evaluated. Variations on hematological parameters in animals fed diets with whole yeast; autolyzed yeast and yeast cell wall were observed to be within normal ranges for this species. There was significant influence (p<0.05 of different levels of yeast and derivatives on intestinal villus perimeter

  2. Physical and chemical quality of water in closed recirculation system during the cultivation of Nile tilapia juvenilesQualidade física e química da água em sistema fechado de recirculação durante o cultivo de juvenis de tilápia-do-Nilo

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    Nilton Garcia Marengoni

    2013-05-01

    Full Text Available The study aimed to evaluate the effect of the filter and time of cultivation of Nile tilapia juveniles in water quality in closed recirculating system. There were used 1,350 fingerlings of Nile tilapia (Oreochromis niloticus in a randomized block experimental design and split-plot time with twelve treatments and three replicates. The treatments were a combination of two local of water harvesting (before the mechanical filter and after the biological filter and six periods of cultivation (14, 28, 42, 56, 70 and 84 days, in a split plot arrangement. The water temperature, dissolved oxygen, oxygen saturation, electrical conductivity and pH did not affect the development of the fish in closed recirculating water. It was observed that the water collected after the biological filter had better physical and chemical quality than that collected before the mechanical filter. The dissolved oxygen levels in the water after the biological filter were higher (PO trabalho teve por objetivo avaliar o efeito do filtro e do tempo de cultivo de alevinos de tilápia-do-Nilo sobre a qualidade de água do sistema de recirculação fechado. Foram utilizados 1.350 alevinos de tilápia-do-Nilo (Oreochromis niloticus em delineamento experimental de blocos casualizados e esquema de parcelas subdivididas no tempo, com doze tratamentos e três repetições. Os tratamentos foram constituídos pela combinação de dois locais de coleta de água (antes do filtro mecânico e após o filtro biológico e de seis tempos de cultivo (14, 28, 42, 56, 70 e 84 dias, em esquema de parcelas subdivididas. A temperatura, oxigênio dissolvido, saturação de oxigênio, condutividade elétrica e pH não afetaram a desenvolvimento dos peixes em sistema fechado de recirculação de água. Observou-se que a água coletada após o filtro biológico apresentou melhor qualidade física e química que a coletada antes do filtro mecânico. Os níveis de oxigênio dissolvido na água após o filtro

  3. Desempenho de diferentes linhagens de tilápia do Nilo (Oreochromis niloticus na fase de reversão sexual - DOI: 10.4025/actascianimsci.v26i3.1794 Performance of different Nile tilapia (Oreochromis niloticus strains, during sex reversal phase - DOI: 10.4025/actascianimsci.v26i3.1794

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    Margarida Maria Barros

    2004-04-01

    Full Text Available O experimento utilizou 4 linhagens de tilápias do Nilo (Oreochromis niloticus chamadas de CESP, Pernambuco, Santa Catarina e Tailandesa. O objetivo do projeto foi comparar o desempenho e a sobrevivência dessas diferentes linhagens de tilápia do Nilo na fase de reversão sexual. As pós-larvas foram estocadas em aquários de 4,5L em sistema de recirculação e com temperatura constante. Os peixes foram alimentados com ração contendo 60mg/kg de 17 alfa-metiltestosterona, fornecida 6 vezes ao dia, por período de 30 dias. O delineamento foi inteiramente casualizado com 4 tratamentos (linhagens e 7 repetições. Os parâmetros avaliados foram: comprimento total, ganho de peso, taxa de crescimento específico, taxa de sobrevivência e eficiência de reversão sexual. Os dados foram submetidos à análise de variância e as médias comparadas pelo teste de Tukey. A análise de reversão foi submetida ao teste de qui-quadrado. O resultado demonstra que houve maior eficiência na taxa de reversão sexual nas linhagens Santa Catarina e Pernambuco quando comparados com a CESP e a Tailandesa. As linhagens Tailandesa e Santa Catarina obtiveram maior taxa de sobrevivência e desempenho satisfatório durante a fase de reversão sexual, portanto, apresentam-se como as mais propícias para a criação em sistema de recirculação na fase de reversão sexual.This experiment aimed at comparing growth performance and survival of four Nile tilapia (Oreochromis niloticus strains called CESP, Pernambuco, Santa Catarina and Thailand in sex reversal phase. Thirty Nile tilapia fries were stocked in 4.5L aquaria (6.66 fries/L with recirculation system and water temperature control. The fishes were fed with ration containing 60mg/kg of 17 alpha-methyltestosterone, six times a day during 30 days. The experimental design was randomized with four treatments (strains and seven replications. Total length, weight gain, specific growth rate, survival rate and sexual

  4. Coeficientes de digestibilidade aparente da energia e nutrientes de alguns ingredientes pela tilápia-do-nilo, Oreochromis niloticus (L. (linhagem tailandesa Apparent digestibility coefficients of energy and nutrients of some ingredients for Nile tilapia, Oreochromis niloticus (L. (Thai strain

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    Wilson Massamitu Furuya

    2001-05-01

    Full Text Available Foram determinados a energia digestível e os coeficientes de digestibilidade aparente de nutrientes de alguns ingredientes pela tilápia-do-nilo (25,24 ± 3,88 g. Os peixes foram alimentados com dietas peletizadas até à saciedade aparente e o valor de digestibilidade de cada ingrediente foi obtido por comparação com a digestibilidade da dieta referência (33% proteína bruta e 0,1% óxido de crômio. Os valores de energia digestível encontrados foram de 3607,47; 2701,24; 3114,54 e 4008,95 kcal/kg para o milho, farelo de trigo, farelo de soja e farinha de peixe, respectivamente. Os coeficientes de digestibilidade aparente obtidos foram de 87,12; 78,21; 92,72 e 84,95%, para a proteína, 94,40; 87,12; 78,21; 92,72;