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

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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.

Apparent digestibility coefficient of duckweed (Lemna minor), fresh and dry for Nile tilapia (Oreochromis niloticus L.)

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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%),

Impact of replacing fish meal by a mixture of different plant protein sources on the growth performance in Nile Tilapia (Oreochromis niloticus L.) diets.

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Al-Thobaiti, A; Al-Ghanim, K; Ahmed, Z; Suliman, E M; Mahboob, S

2017-10-23

The present study aimed to assess the appropriate level of replacement of fish meal (FM) with alternative plant sources in the feed fed to Oreochromis niloticus to evaluate the growth performance. Three isoproteinious (40% crude protein) diets were prepared from different ingredients viz., fish meal, corn gluten meal, wheat gluten meal, and bagasse kenna meal. O. niloticus showed a maximum increase in weight as 9.70, 11.09, 8.53 and 8.32 g during the 2nd, 2nd, 3rd and 2nd fortnight with feeding treatment A, B, C and D, respectively. The growth performance of the fish in terms of weight gain, specific growth rate, feed conversion ratio and protein efficiency ratio were found to be significantly (P replacement of fishmeal in diet B. The worst growth performance was observed in fish fed with commercial diet, designated as diet D. It was concluded that the fish meal can be replaced up to 20 percent with other plant protein sources without any negative impact on fish health. The replacement of fish meal with local plant sources (corn gluten meal, wheat gluten meal, soybean meal and bagasse kenna mix) will not only be beneficial to achieve better growth performance in O. niloticus, it will be a value addition as well.

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.

assimilation efficiency in two herbivores, oreochromis niloticus and ...

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ABSTRACT: The abilities of two herbivorous animals (Oreochromis niloticus and the larva ... improved lyses of algal cells. ... Thus, more studies to understand how these and other factors affect ... as plant cells are surrounded by cell wall, and.

Molecular identification and pathogenicity of Citrobacter and Serratia species isolated from cultured Oreochromis niloticus

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Manal I. El-Barbary

2017-09-01

Full Text Available This study aimed to isolate and characterize some pathogenic bacterial strains belonging to the family Enterobacteriaceae. They had been isolated from gills, liver, kidney and skin of naturally infected Oreochromis niloticus and had been identified by biochemical test and 16S rRNA gene using four universal primers. Additionally, the isolates were tested for antimicrobial susceptibility, histopathological alterations of liver, kidney and gills and the pathogenicity of the identified isolates for O. niloticus. The results of phylogenetic analysis placed the isolates in the family Enterobacteriaceae (genera Serratia and Citrobacter based on 99% homology. The primer pair (17F and 1390R is the most appropriate pair of universal primers employed for the identification of 16S rRNA gene as it covers as much as possible of the variable regions (Vs. V1 and V2 regions of 16S rRNA gene presented weak evidence of the diversity of the genera Serratia. The mortality rate was 40–60% after challenging O. niloticus by identified isolates, which revealed its sensitivity to ciprofloxacin and norfloxacin. Histological changes showed dilation in sinusoids with severe vacuolar degeneration in the liver, tubular degeneration and hemorrhage between renal tubules with pyknotic nuclei in the kidney, epithelial hyperplasia, aneurism and evident epithelium interstitial edema in gills of O. niloticus. This study concluded that these isolates should be considered as an opportunistic pathogen of O. niloticus. The study also states that the sequencing of 16S rRNA is an important tool for the identification of unknown bacterial species of fish pathogen. Keywords: Citrobacter sp., Serratia sp., Phylogenetic analysis, Histology, Antibiotic sensitivity, Oreochromis niloticus

The radiosensitivity of nile tilapia (Oreochromis niloticus) fingerlings

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Reyes, Michael Joseph T.; Velasco, Pia Victoria V.

2000-04-01

The nile tilapia (Oreochromis niloticus), a very popular fish commercially in the Philippines, was studied to determine its radiosensitivity and to see its potential as a biological indicator in aquatic ecosystems. Nile tilapia was seen to be radiosensitive. The fish were exposed to gamma-irradiation and chromosomal aberrations were induced. The various types of aberrations seen were chromatid gaps, chromosome gaps, chromatid fragments, dicentric rings, fusions, despiralizations and translocations. Among the aberrations observed, dicentric rings, fusions and chromosome gaps were strongly correlated with dosage, with only the dicentric rings increasing steadily with increasing dosage. In the course of the study, the lethal dosage 50 for nile tilapia with 18 days was determined and it was observed at 2.0 krad. The modal chromosome number was also established at 2n=44 with a karyotype exhibiting 22 pairs of acrocentric chromosomes with 2 pairs of marker chromosomes present. (Author)

The radiosensitivity of nile tilapia (Oreochromis niloticus) fingerlings

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Reyes, Michael Joseph T; Velasco, Pia Victoria V

2000-04-01

The nile tilapia (Oreochromis niloticus), a very popular fish commercially in the Philippines, was studied to determine its radiosensitivity and to see its potential as a biological indicator in aquatic ecosystems. Nile tilapia was seen to be radiosensitive. The fish were exposed to gamma-irradiation and chromosomal aberrations were induced. The various types of aberrations seen were chromatid gaps, chromosome gaps, chromatid fragments, dicentric rings, fusions, despiralizations and translocations. Among the aberrations observed, dicentric rings, fusions and chromosome gaps were strongly correlated with dosage, with only the dicentric rings increasing steadily with increasing dosage. In the course of the study, the lethal dosage{sub 50} for nile tilapia with 18 days was determined and it was observed at 2.0 krad. The modal chromosome number was also established at 2n=44 with a karyotype exhibiting 22 pairs of acrocentric chromosomes with 2 pairs of marker chromosomes present. (Author)

Identification of Oreochromis niloticus (Linnaeus, 1758) and Tilapia ...

African Journals Online (AJOL)

Isoelectric focusing methodology using LKB 2117 Multiphor 11 electrofocusing apparatus was used for electofocusing and identification of Oreochromis niloticus and Tilapia zilli. The electrographs of the two species suggest clear protein differences producing species specific patterns. There were variations in the protein ...

Isolation of fish skin and bone gelatin from tilapia (Oreochromis niloticus): Response surface approach

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Arpi, N.; Fahrizal; Novita, M.

2018-03-01

In this study, gelatin from fish collagen, as one of halal sources, was extracted from tilapia (Oreochromis niloticus) skin and bone, by using Response Surface Methodology to optimize gelatin extraction conditions. Concentrations of alkaline NaOH and acid HCl, in the pretreatment process, and temperatures in extraction process were chosen as independent variables, while dependent variables were yield, gel strength, and emulsion activity index (EAI). The result of investigation showed that lower NaOH pretreatment concentrations provided proper pH extraction conditions which combine with higher extraction temperatures resulted in high gelatin yield. However, gelatin emulsion activity index increased proportionally to the decreased in NaOH concentrations and extraction temperatures. No significant effect of the three independent variables on the gelatin gel strength. RSM optimization process resulted in optimum gelatin extraction process conditions using alkaline NaOH concentration of 0.77 N, acid HCl of 0.59 N, and extraction temperature of 66.80 °C. The optimal solution formula had optimization targets of 94.38%.

Effect of lead nitrate on the liver of the cichlid fish (Oreochromis niloticus): a light microscope study.

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Khidr, Bothaina M; Mekkawy, Imam A A; Harabawy, Ahmed S A; Ohaida, Abdel Salam M I

2012-09-15

The adverse impacts of heavy metals on fish liver were evident with great variability among organs and species. The present study deals with the histological changes of the hepatocytes of the Nile tilapia, Oreochromis niloticus, following exposure to 2.5, 5, 10 ppm of lead nitrate for 1, 2, 3, 4 weeks. The present results revealed that lead nitrate exerts some histological effects on the hepatic tissue after exposure to the first concentration in the form of dilatation and congestion of the blood vessels, vacuolation of hepatic cells, proliferation of connective tissue and hepatic necrosis. Leucocyte aggregation-mostly lymphatic in nature-was seen infiltrating hepatic tissue. These alterations became more pronounced in liver of fishes exposed to second concentrations indicating more progressive signs of necrosis. The presence of eosinophilic oedematous areas surrounding some blood vessels was also observed. Finally, at the third concentration, in addition to the above alterations, melanomacrophages, which store lipofuscin at the site of necrosis, were observed. These histological results imply that the fish liver may serve as a target organ for the toxicity of sublethal concentrations of lead nitrate.

Antibiotic resistence of Aeromonas hydrophila isolated from Piaractus mesopotamicus (Holmberg, 1887) and Oreochromis niloticus (Linnaeus, 1758)

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Belém-Costa,Andréa; Cyrino,José Eurico Possebon

2006-01-01

One of the most important problems involving treatments with antibiotics against Aeromonas hydrophila isolated from fishes is that antibiotic resistance develops readily. The antimicrobial activity of chemotherapeutants in isolates from pacu Piaractus mesopotamicus (Holmberg, 1887) and tilapia Oreochromis niloticus (Linnaeus, 1758) was tested by the Kirby-Bauer disk method, over Mueller-Hinton surface agar previously inoculated with 100 µL of bacterial suspensions. After regular incubation, i...

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.

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

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Zago, Aline Cristina; Franceschini, Lidiane; Garcia, Fabiana; Schalch, Sérgio Henrique Canello; Gozi, Kátia Suemi; Silva, Reinaldo José da

2014-01-01

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. niloticus in 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 Epistylis sp.) 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.

Induction of hsp70 by the herbicide oxyfluorfen (Goal) in the Egyptian Nile fish, Oreochromis niloticus.

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Hassanein, H M; Banhawy, M A; Soliman, F M; Abdel-Rehim, S A; Müller, W E; Schröder, H C

1999-07-01

This paper deals with the expression of the biomarker hsp70 in the liver and kidney of the freshwater fish Oreochromis niloticus following exposure to the herbicide oxyfluorfen (Goal). Fishes were exposed to three concentrations, the 96-h LC50 (3 mg/L), the 96-h (1/2)LC50 (1.5 mg/L), and the 96-h (1/4)LC50 (0.75 mg/L) of oxyfluorfen for 6, 15, and 24 days, respectively, and samples were taken at three different time periods for each concentration. The livers responded to the herbicide by an induction of the expression of both the constitutive (hsp75; Mr 75 kDa) and the inducible (hsp73; Mr 73 kDa) hsp70 proteins. In kidney, the herbicide induced a time-dependent increase in the expression of the constitutive hsp70 (hsp75) as well, but the inducible hsp70 (hsp73) required much longer incubation periods to reach maximal levels (15 and 24 days). Our results suggest that expression of hsp70 in fish is a sensitive indicator of cellular responses to herbicide exposure in the aquatic environment.

Pertumbuhan dan Kelangsungan Hidup Benih Ikan Nila Gesit (Oreochromis Niloticus) pada Sistem Akuaponik dengan Jenis Tanaman yang Berbeda

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Mulqan, Muhammad; El Rahimi, Sayyid Afdhal; Dewiyanti, Irma

2017-01-01

Aquaponics system is a farming system which saving land use and improving the efficiency of nutrient utilization of residual feed and fish metabolism. This system is environmentally friendly fish farming. This research was aimed to measure the growth and survival rate of tilapia (Oreochromis niloticus) on the use of Aquaponics system with different plant species. The difference treatment consisted of four treatments and three repetitions which used plant kale, collards, lettuce and control. R...

Effect of grilling and baking on physicochemical and textural properties of tilapia (Oreochromis niloticus) fish burger.

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Bainy, Eduarda Molardi; Bertan, Larissa Canhadas; Corazza, Marcos Lucio; Lenzi, Marcelo Kaminski

2015-08-01

The influence of two common cooking methods, grilling and baking, on chemical composition, water retention, fat retention, cooking yield, diameter reduction, expressible water, color and mechanical texture of tilapia (Oreochromis niloticus) fish burgers was investigated. Texture analyses were performed using a Warner-Bratzler test. The fish burger had a softer texture with a lower shear force than other meat products reported in the literature. There were no significant differences in proximate composition, diameter reduction, fat retention and expressible water between the grilled and oven-baked fish burgers. Cooking methods did not affect the cooking times and cooking rates. Warner-Bratzler parameters and color were significantly influenced by the cooking method. Grilling contributed to a shear force and work of shearing increase due to the lower cooking yield and water retention. Raw burgers had the highest L* (69.13 ± 0.96) and lowest b* (17.50 ± 0.75) values. Results indicated that baking yielded a product with better cooking characteristics, such as a desired softer texture with lower shear values (4.01 ± 0.54) and increased water retention (95.82 ± 0.77). Additionally, the baked fish burgers were lighter (higher L*) and less red (lower a*) than the grilled ones.

Biomarkers in an invasive fish species, Oreochromis niloticus, to assess the effects of pollution in a highly degraded Brazilian River.

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Linde-Arias, Ana Rosa; Inácio, Alan F; de Alburquerque, Carla; Freire, Marina M; Moreira, Josino C

2008-07-25

Paraiba do Sul watershed is one of the most important Brazilian water bodies (5.5 million people depend on the river). It is in a critical environmental situation, polluted by industrial discharges, non-treated urban wastes, and pesticides, which have had cumulatively negative effects. This study analyzes the effects of pollution, with a biomarker approach, by using the invasive fish species, Oreochromis niloticus, as a sentinel species. The approach comprehends a general biomarker of the health of individual fish, the condition factor, a biomarker of genotoxicity, the micronuclei test; and specific biomarkers of contaminant exposure such as metallothionein (MT) and acetylcholinesterase (AChE) activity. The results revealed different effects in fish from diverse locations with varying degrees of pollution. Low AChE activities were found in fish from the region with strong agriculture activity, showing the effects of pesticides. Fish from an industrialized and heavily environmentally degraded area presented high levels of MT and low AChE activities, indicating an intricate polluted condition. It is noteworthy that fish located just upstream of the main water-treatment plant of the metropolitan area Rio de Janeiro presented high levels of MT, showing to be affected by metals. This can be an alert to public health officials. O. niloticus has proven a suitable sentinel species to assess the effects of pollutions in an aquatic system with a complex and serious polluted situation. The present study also shows the usefulness of integrating a set of biomarkers to define the exposure and the effects of anthropogenic inputs among impacted and reference sites in this water body.

Effect of The Phytase Enzyme Addition in The Artificial Feed on Digestibility of Feed, Feed Conversion Ratio and Growth of Gift Tilapia Saline Fish (Oreochromis niloticus) Nursery Stadia I

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Rachmawati, Diana; Samidjan, Istiyanto; Elfitasari, Tita

2018-02-01

The purpose of this study was to determine the effect of adding the phytase enzyme in the artificial feed on digestibility of feed, feed conversion ratio and growth of gift tilapia saline fish (Oreochromis niloticus) nursery stadia I. The fish samples in this study used gift tilapia saline fish (O. niloticus) with an average weight of 0,62 ± 0,008 g/fish and the stocking density of 1 fish1 L. Experimental method used in this study was completely randomized design with 4 treatments and 3 repetitions. The treatments were by adding phytase enzyme in artificial feed with the different level of doses those were A (0 FTU kg1 feed), B (500 FTU kg1 feed), C (1000 FTU kg1 feed) and D (1500 FTU kg1 feed). The results show that the addition of phytase enzyme was significantly (P0.05) affected on Survival Rate (SR) of gift tilapia saline fish. The optimum doses of phytase enzyme on RGR, FCR, PER, ADCP and ADCF of gift tilapia saline fish ranged from 1060 to 1100 FTU kg-1 feed.

Hybridations des taxons Oreochromis niloticus (Linnée, 1758) aux ...

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Oreochromis niloticus,. Sarotherodon melanotheron ... confirme les hybridations dans la station expérimentale d'aquaculture de Layo, par l'existence de divers taxons recombinés dont les ... des croisements interspécifiques non contrôlées, provoquant ...

Mode d'exploitation et durabilité de la pêche de Oreochromis niloticus (Linnaeus, 1758, Clarias gariepinus (Burchell, 1822 et Gymnarchus niloticus (Cuvier, 1829 dans le lac de barrage du Sourou (Burkina Faso

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Dialla, Z.

2016-01-01

Full Text Available Mode of Operation and Sustainability of Oreochromis niloticus (Linnaeus, 1758, Clarias gariepinus (Burchell, 1822 and Gymnarchus niloticus (Cuvier, 1829 Fisheries in the Sourou Dam Lake (Burkina Faso. This research on fishery exploitation in the Sourou dam raises the issue of sustainable management of common property. The central hypothesis is that the effectiveness of co-management for sustainable fishing practices is related to the level of ownership of that management and actors' games by fishing communities. In analysing co-management induced effects on fishing practices and exploitation of C. gariepinus, O. niloticus and G. niloticus species, related to its implementation in Sourou fishery, a research methodology that combines qualitative and quantitative methods is used. Socio-economic surveys were conducted with 30 fishermen in three villages bordering the fishery. Biological surveys were also conducted with catches of C. gariepinus, O. niloticus and G. niloticus of these fishermen,. The results indicate a weak ownership of the co-management model by fishermen and the strategies of actors that consist to minimize the costs of the sustainable management of fisheries resources at individual level. Indeed, even when informed of fisheries regulations, fishermen use prohibited fishing equipment (54.1% of the catches of studied species, and fishi illegally (43.3% of the fishermen. Furthermore, significant proportions of each studied species are captured before their first maturity sizes (52.2% of C. gariepinus, 15.8% of G. niloticus and 14.3% of O. niloticus. So, the central hypothesis is verified because the weak ownership of co-management by fishing communities and the actors' strategies do not encourage them to develop a responsible behavior for sustainable fishing.

Alterações histológicas em brânquias de tilápia nilotica Oreochromis niloticus causadas pelo cádmio Histological alterations in gills of Nile tilapia Oreochromis niloticus caused by cadmium

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S. Garcia-Santos

2007-04-01

Full Text Available Os efeitos histopatológicos do cádmio nas brânquias de tilápia Oreochromis niloticus foram estudados por microscopia óptica, usando 25mgl-1 de CdCl2 durante quatro dias, com o objetivo de identificar seus efeitos agudos na estrutura das brânquias. A morfologia geral das brânquias de O. niloticus é idêntica à de outros teleósteos, apresentando quatro pares de arcos branquiais com filamentos bem desenvolvidos. Situadas lateralmente, encontram-se as lamelas provenientes do eixo central dos filamentos. No epitélio filamentar foi possível identificar células de cloro, pavimentosas e mucosas. Os peixes expostos ao cádmio mostraram sinais de lesões epiteliais; edema intersticial, vasodilatação das lamelas, destacamento do epitélio lamelar e proliferação do epitélio filamentar. As alterações observadas também incluíram fusão nas lamelas como resultado de hiperplasia e hipertrofia epitelial, ruptura do sistema de células pilar, aneurismas e necroses.The histopathogical effects of cadmium on the gills of tilapia Oreochromis niloticus were studied by light microscopy, using 25mgl-1 of CdCl2 during four days to identified the effects of short-term exposure on gills structure. The general morphology of O. niloticus gills is similar to the other teleostean fishes, showing four pairs of gills arches with well developed filaments. Bilaterally situated, secondary lamellae branches are found from the central axis of the filaments. The filamentar epithelium showed the chloride cells, the pavement cells and mucous cells. Fish exposed to cadmium showed signs of epithelial lesion, namely the interstitial edema, swollen of the lamellae, lifting and cellular proliferation of the filamentar epithelium. The changes of the gills also included lamellar fusion as a result of epithelial hyperplasia and hypertrophy, the breakdown of pillar cell system, and aneurisms with some ruptures and necrosis, especially in the filamentar epithelium.

Recent introgressive hybridization revealed by exclusive mtDNA transfer from Oreochromis leucostictus (Trewavas, 1933) to Oreochromis niloticus (Linnaeus, 1758) in Lake Baringo, Kenya

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Nyingi, Dorothy W.; Agnèse, Jean-François

2007-01-01

Nuclear DNA and mtDNA polymorphisms were surveyed in various species of East African Oreochromis. In Lake Baringo, where only Oreochromis niloticus baringoensis is present, alien mtDNA haplotypes were observed, apparently the result of introgressive hybridization with Oreochromis leucostictus. This introgression is not accompanied by any substantial or recorded transfer of nuclear genes into O. n. baringoensis.

Experimental infection of Tilapia Lake Virus (TiLV) in Nile tilapia (Oreochromis niloticus) and red tilapia (Oreochromis spp.).

Science.gov (United States)

Tattiyapong, Puntanat; Dachavichitlead, Worawan; Surachetpong, Win

2017-08-01

Since 2015, a novel orthomyxo-like virus, tilapia lake virus (TiLV) has been associated with outbreaks of disease and massive mortality of cultured Nile and red tilapia (Oreochromis niloticus and Oreochromis spp., respectively) in Thailand. In this study, TiLV was isolated from field samples and propagated in the permissive E-11 cell line, with cytopathic effect (CPE) development within 3-5days post-inoculation. Electron micrographs of infected E-11 cells and fish tissues confirmed the rounded, enveloped virions of 60 to 80nm with characteristics very similar to those of Orthomyxoviridae. In vivo challenge studies showed that high mortality in Nile (86%) and red tilapia (66%) occurred within 4-12days post-infection. The virus was re-isolated from challenged fish tissues in the permissive cell line, and PCR analysis confirmed TiLV as a causative pathogen. The distinct histopathology of challenged fish included massive degeneration and inflammatory cell infiltration in the liver and brain as well as the presence of eosinophilic intracytoplasmic inclusions in hepatocytes and splenic cells. Our results fulfilled Koch's postulates and confirmed that TiLV is an etiologic agent of mass mortality of tilapia in Thailand. The emergence of this virus in many countries has helped increase awareness that it is a potential threat to tilapia aquacultured in Thailand, Asia, and worldwide. Copyright © 2017 Elsevier B.V. All rights reserved.

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

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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

Rodlet cells changes in Oreochromis niloticus in response to organophosphate pesticide and their relevance as stress biomarker in teleost fishes

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Natalia de Souza Araujo

2016-01-01

Full Text Available Rodlet cells are frequently found in teleost fishes and although their role in organisms is not completely understood. The occurrence of these cells are related to stress and may undergo changes in contaminated environments, thereby allowing their use as biomarkers. This hypothesis is tested in the present study. Thirty specimens of Oreochromis niloticus were divided into three groups, two groups were exposed to organophosphate pesticide methyl parathion at nominal concentrations of 4 mgl-1 and 8 mgl-1 and one group was kept as control. After ten days, the gills were removed for microscopic study and the number and area of the rodlet cells were analyzed and compared with a well-established method of assessing histological damages in fishes. No significant differences were found in the area of the cells, but there were significant differences in the number of rodlet cells among examined concentrations. The present study provides evidence for the use of this new biomarker in teleost fishes and discusses some of the potential confounding factors of this approach.

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

-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...

Production de Oreochromis niloticus avec des aliments à base de ...

African Journals Online (AJOL)

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... (LEBA), UFR des Sciences et Gestion de l'Environnement, Université ... Des alevins de Oreochromis niloticus (0,7 ± 0,06 g) ont été nourris dans seize ... de poisson, est un produit industriel et a servi de témoin. .... stock d'alevins récoltés.

Digestibility, growth, blood chemistry, and enzyme activity of juvenile Oreochromis niloticus fed isocaloric diets containing animal and plant byproducts

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Magnolia Montoya-Mejía

Full Text Available ABSTRACT In this work, we studied the digestibility, growth, blood chemistry, and enzyme activity of Nile tilapia (Oreochromis niloticus juveniles (0.95±0.18 g using different animal (fish silage meal, whey meal, bovine blood meal, and red crab meal and plant (extruded bean, extruded chickpea meal, coconut paste, Jatropha curcas meal, and chickpea meal dietary byproducts. Nine isocaloric diets (321.92±9.10 kcal g−1 were evaluated for 60 days. The highest digestibility of crude protein values for animal and plant sources were obtained for the whey (93.6 and extruded bean meal (90.5 diets, respectively. The final body weight was higher for the red crab and extruded chickpea meal diets, meanwhile the fish silage and red crab byproducts obtained the highest protein efficiency ratio. Hematocrit was similar among the diets of each byproduct source and presented correlation with growth parameters. The highest glucose, cholesterol, and triglyceride values were obtained for fish silage (138.0, 260.5, and 389.0 mg dL−1, respectively and whey meal (174.5, 242.3, and 284.0 mg dL−1, respectively groups. A positive correlation was found between the digestibility of crude protein of ingredients and chymotrypsin activity. Oreochromis niloticus is able to better utilize fish silage, whey, extruded bean, and extruded chickpea byproducts, adjusting its digestive physiology. Such ingredients can be used for formulating cheaper and efficient tilapia diets.

Toxicidade aguda de herbicidas a tilápia (Oreochromis niloticus Acute toxicity to herbicides to Oreochromis niloticus

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R.G. Botelho

2009-01-01

Full Text Available Esta pesquisa teve como objetivo avaliar a sensibilidade de alevinos de Oreochromis niloticus a diversos herbicidas. Para isso, foram realizados dois ensaios, sendo, no primeiro, avaliadas concentrações de atrazina (0; 2,5; 5; 10; e 20 mg L-1, visando a determinação da concentração letal a 50% dos indivíduos (CL50, e, no segundo, a sensibilidade às mesclas dos herbicidas alachlor + atrazina (5,33 + 5,33 mg L-1, diuron + MSMA (5,33 + 2,13 mg L-1, paraquat (1,33 mg L-1 e 2,4-D + picloram (1,28 + 0,34 mg L-1, com contagem de mortes 96 horas após exposição aos produtos. No primeiro ensaio foi observado elevado declínio na sobrevivência dos alevinos a partir de 3 mg L-1 do herbicida atrazina, com CL50 estimada de 5,02 mg L-1. No segundo, a mistura alachlor + atrazina promoveu o maior efeito de mortalidade sobre os alevinos de tilápia. Com 72 horas de exposição, a escala de intoxicação evidenciou redução nos números de indivíduos de, aproximadamente, 17,4% para os produtos paraquat, 2,4-D + picloram e diuron + MSMA e de 100% para alachlor + atrazina. Os dados permitem concluir que a CL50 obtida para o atrazina é inferior àquela mencionada como tóxica para truta e que a mistura alachlor + atrazina pode ser caracterizada como de risco para O. niloticus, mesmo quando aplicada em doses normais de uso.Two assays were carried out to evaluate Oreochromis niloticus sensitivity to different herbicides. In the first experiment, atrazin concentrations (0; 2.5; 5; 10 and 20 mg L-1 were evaluated aiming to determine lethal concentration (LC50 to O. niloticus. In the second assay, the effects of the herbicide mixtures alachlor + atrazin (5.33 + 5.33 mg L-1, diuron + MSMA (5.33 + 2.13 mg L-1 , paraquat (1.33 mg L-1 and 2,4-D + picloran (1.28 + 0.34 mg L-1 , were evaluated on O. niloticus survival after 96 h of exposure. In the first assay, a sharp decrease in fingerlings survival was observed from 3 mg L-1 of atrazin with CL50 value of 5

Eubiotic effect of a dietary acidifier (potassium diformate) on the health status of cultured Oreochromis niloticus

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Abu Elala, Nermeen M.; Ragaa, Naela M.

2014-01-01

In connection with the global demand for safe human food and the production of environmentally friendly aquaculture products, acidifiers are natural organic acids and salts that have received considerable attention as animal-feed additives. The current study was designed to evaluate the effects of potassium diformate (KDF) on the growth performance and immunity of cultured Oreochromis niloticus (O. niloticus). Four iso-nitrogenous and iso-caloric rations containing graded levels of KDF, including 0% (control basal diet), 0.1%, 0.2% and 0.3%, were fed separately to four equal fish groups (30 fish/group with an initial body weight of 53.49 ± 6.15 g) for sixty days. At the end of the experimental period, the fish groups fed on 0.2% and 0.3% KDF exhibited significant improvements in their feed intake, live weight gain, specific growth rate, feed conversion ratio and protein efficiency ratio, with concomitant improvement of their apparent protein digestibility (p fish groups fed on KDF and challenged orally with Aeromonas hydrophila was lower than that of the control group. The resistance against diseases increased with dietary KDF in a dose-dependent manner. Thus, we conclude that the use of acidifiers can be an efficient tool to achieve sustainable, economical and safe fish production. PMID:26199753

Dietary supplementation of yeast (Saccharomyces cerevisiae) improves growth, stress tolerance, and disease resistance in juvenile Nile tilapia (Oreochromis niloticus)

DEFF Research Database (Denmark)

Abass, David Attim; Obirikorang, Kwasi Adu; Campion, Benjamin Betey

2018-01-01

resistance in juvenile (body mass ~ 21 g) Nile tilapia (Oreochromis niloticus). Fish were randomly distributed in groups of 20 into 12 1-m³ hapas and fed isoenergetic (~ 17 kJ g⁻¹ gross energy) and isonitrogenous (~ 300 g kg⁻¹ crude protein) diets at 3% of their bulk weight daily. Specific growth rates were...... as an additive in Nile tilapia diets has beneficial impacts on growth, stress tolerance, and disease resistance...

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

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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.

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

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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. Copyright © 2015 Elsevier Ltd. All rights reserved.

Pertumbuhan dan rasio konversi pakan ikan nila (Oreochromis niloticus dengan penambahan prebiotik

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NITA ARDITA

2015-05-01

Full Text Available Ardita N, Budiharjo A, Sari SLA. 2015. Growth and feed conversion ratio of tilapia fish (Oreochromis niloticus with addition of probiotics. Bioteknologi 12: 16-21. The problems of tilapia farming are the high feed costs and long cultivation time. Feed costs is in the ranges 60-70% from the total cost. Probiotics in the digestive tract will improve the digestion and absorbtion of nutrients. This study was aimed to determine the effect of probiotics on tilapia growth and feed conversion ratio (FCR. This study used a completely randomized design with 4 treatments i.e. 0%, 3%, 4%, and 5% (v/w of probiotic in feed. Probiotics was sprayed into comercial pellets. Tilapia were cultivated for 2 months given by commercial pellets with different proportion of probiotics. The parameters measured were the growth of fish (fish length and fish weight, Survival Rate (SR and FCR. Data was analyzed by ANOVA. The results showed that the addition of probiotics dose 0%, 3%, 4%, and 5% (v/w did not affect significantly to the growth and feed conversion ratio for 8 weeks.

Optimal feeding rate for Nile tilapia (Oreochromis niloticus)

OpenAIRE

Chowdhury, Dilip Kumar

2011-01-01

The aim of this study was to define optimal feeding rates for Nile tilapia (Oreochromis niloticus). Four experiments were carried out to evaluate the effect of feeding rate on growth performance of larger and juvenile tilapia by means of estimating growth rates, apparent nutrient digestibilities, feed utilization, body compositions, and nutrient and energy retentions. One nutritionally balanced diet (crude protein 342, crude fat 67, ash 47, starch 251 (all values in g (kg dry matter)-1)) was ...

Use of distiller’s dried grains with solubles, which had been used as substrate for black soldier fly larvae, in diets for nile tilapia Oreochromis niloticus

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A feeding trial was conducted in a closed system with Nile tilapia, Oreochromis niloticus, juveniles (mean initial weight, 2.66 g) to examine total replacement of menhaden fish meal (MFM) with distiller’s dried grains with solubles (DDGS), which had been used as substrate for the production of black...

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

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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.

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

Digestibility and postprandial ammonia excretion in Nile tilapia (Oreochromis niloticus) fed diets containing different oilseed by-products

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

2015-01-01

The present study was undertaken to evaluate the potential for using oilseed by-products (soybean, copra and palm kernel meals) as partial replacements of fishmeal in feeds for Nile tilapia (Oreochromis niloticus). Nutrient digestibility and postprandial ammonia excretion rates were examined....... A fishmeal-based diet served as control against three test diets in which 30 % of each of the oilseed by-products was included. Diets were randomly assigned to triplicate groups of fish (similar to 1 kg bulk weight) for the digestibility trials which spanned a total of 9 days. The partial inclusion...

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

Effects of replacing fish meal with rubber seed meal on growth, nutrient utilization, and cholesterol metabolism of tilapia (Oreochromis niloticus × O. aureus).

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Deng, Junming; Wang, Kun; Mai, Kangsen; Chen, Liqiao; Zhang, Lu; Mi, Haifeng

2017-08-01

A feeding trial was conducted to evaluate the effects of replacing fish meal with rubber seed meal (RSM) on growth, nutrient utilization, and cholesterol metabolism of tilapia (Oreochromis niloticus × Oreochromis aureus). Five experimental diets were formulated with 0, 150, 300, 450, and 600 g kg -1 RSM replacing graded levels of fish meal, respectively. Each diet was randomly assigned to triplicate groups of 25 fish (initial average weight 65.3 g) per aquarium in a rearing system maintained at 29 ± 1 °C for 8 weeks. Dietary 150 g kg -1 RSM inclusion did not affect the weight gain and daily growth coefficient, whereas these were depressed by a further inclusion. Additionally, feed efficiency ratio and protein efficiency ratio were not affected by dietary RSM inclusion regardless of inclusion level. However, the inclusion of 450 and 600 g kg -1 RSM decreased the mid-intestinal trypsin, lipase, and amylase activities; the hepatic acyl-CoA/cholesterol acyl transferase; low-density lipoprotein receptor; and 3-hydroxy-3-methyl-glutaryl-CoA reductase activities. Similarly, dietary 600 g kg -1 RSM inclusion inhibited the plasma catalase and hepatic glutathione peroxidase activities. These results indicated that 150 g kg -1 RSM can be included in tilapia diets, whereas higher inclusion of RSM inhibited the growth rate, digestive enzyme activity, antioxidant capacity, and cholesterol metabolism.

Evaluation of marking efficiency of different alizarin red S concentrations on body fish structures in Oreochromis niloticus (Perciformes: Cichlidae juveniles

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Ana L. Ibáñez

2013-03-01

Full Text Available The use of alizarin red S (ARS marked tilapias could provide valuable fisheries management information to evaluate fish stocking events and may facilitate aquaculture management practices. As a new technique in fishes, the aim of this study was to compare and evaluate the chemical marks produced in tilapia juveniles by ARS through two treatments: 1 12 hours of immersion and 2 immersion after osmotic induction. This was analyzed at three concentrations: 50, 75 and 100mg/l, and in three structures: otoliths, fish scales and caudal fin rays of Oreochromis niloticus juveniles. After three culture months 80% of specimens were analyzed and significant differences (pEl uso de alizarina roja S (ARS para marcar tilapias podría proporcionar información valiosa para el manejo de su pesquería. Para evaluar pesquerías acuaculturales manejadas con siembras o repoblamientos de peces se comparó y evaluó la marca producida por la alizarina roja S, empleando dos tratamientos: 1 Inmersión en ARS durante 12h; e 2 Inmersión en ARS después de un choque osmótico. El análisis se realizó a tres concentraciones: 50, 75 y 100mg/l y en tres estructuras: otolitos, escamas y radios de la aleta caudal de Oreochromis niloticus. Ochenta por ciento de los ejemplares fueron cultivados durante tres meses y analizados posteriormente. Los resultados mostraron diferencias entre las concentraciones de la marca para el tratamiento de 12h de inmersión mientras que no hubo diferencias entre las concentraciones para el tratamiento con inducción osmótica. Se encontraron diferencias en la intensidad de la marca entre los tratamientos para otolitos y radios de las aletas pero para las escamas no hubo diferencias significativas. Todas las concentraciones produjeron marcas (desde débiles a intensas, sin embargo la concentración de 100mg/l no produjo marcas débiles. El tratamiento por inducción osmótica presentó mayores niveles de mortalidad. Después de ocho meses de

Determination of some heavy metals in oreochromis niloticus, clarias gariepinus and synodontis spp from the coastal water of Ondo State, Nigeria

International Nuclear Information System (INIS)

Asaolu, S.S.

2002-01-01

Some heavy metals (Pb, Ni, Fe, Cu, Zn, Cd, Co, Mn, and Cr) were determined in Oreochromis niloticus, Clarias graiepinus and Synodontis spp obtained from the coastal water of Ondo State. All metals examined and detected in all fish samples. Iron, manganese and cadmium were found to be the most abundant metals in the fish samples with an average values of 35.8, 31.3, and 12.5 mg kg-1 respectively. Except for manganese, iron and cadmium, Syndrontis spp has the highest concentration for virtually all the metals under examination. (author)

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

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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.

Effects of Copper Oxide Nanoparticles on Antioxidant Enzyme Activities and on Tissue Accumulation of Oreochromis niloticus.

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Tunçsoy, Mustafa; Duran, Servet; Ay, Özcan; Cicik, Bedii; Erdem, Cahit

2017-09-01

Accumulation of copper oxide nanoparticles (CuO NPs) in gill, liver and muscle tissues of Oreochromis niloticus and its effects on superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx) activities in gill and liver tissues were studied after exposing the fish to 20 µg/L Cu over 15 days. Copper levels and enzyme activities in tissues were determined using spectrophotometric (ICP-AES and UV) techniques respectively. No mortality was observed during the experiments. Copper levels increased in gill and liver tissues of O. niloticus compared to control when exposed to CuO NPs whereas exposure to metal had no effect on muscle level at the end of the exposure period. Highest accumulation of copper was observed in liver while no accumulation was detected in muscle tissue. SOD, CAT activities decreased and GPx activity increased in gill and liver tissues when exposed to CuO NPs.

Predation of Piaractus mesopotamicus and Oreochromis niloticus larvae by Pantala flavescens with different length classes - doi: 10.4025/actascibiolsci.v33i4.5470 Predation of Piaractus mesopotamicus and Oreochromis niloticus larvae by Pantala flavescens with different length classes - doi: 10.4025/actascibiolsci.v33i4.5470

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Carlos Eduardo Bento Fernandes

2011-09-01

Full Text Available The experiment had as objective to study the survival of Piaractus mesopotamicus and Oreochromis niloticus larvae subject to predation by Pantala flavescens larvae with different length classes. We used 120 larvae of P. mesopotamicus, 120 of O. niloticus, and also 24 larvae of Pantala flavescens, distributed in 24 aquariums with useful volume for 2 L, being placed one Odonate for aquarium. The treatments differed as regard to the prey species and the predator size, being kept a control treatment. An aquarium (2 L containing one larvae of Odonate and 10 larvae of fish were considered an experimental unit. After the beginning, each three hours (18:00, 21:00, 0:00, 3:00, 6:00, 9:00, 12:00, 15:00 and 18:00h, the remnant larvae of fish (alive in each experimental unit was quantified, and we replaced the consumed larvae, so that we always had 10 larvae of fish at each aquarium after each counting. For both fish species, there was a slight increase in consumption by the Odonate with intermediate size, but the values did not differ statistically (p > 0.05. Larvae of Odonate in the treatments with greater length presented a lower consumption (p The experiment had as objective to study the survival of Piaractus mesopotamicus and Oreochromis niloticus larvae subject to predation by Pantala flavescens larvae with different length classes. We used 120 larvae of P. mesopotamicus, 120 of O. niloticus, and also 24 larvae of Pantala flavescens, distributed in 24 aquariums with useful volume for 2 L, being placed one Odonate for aquarium. The treatments differed as regard to the prey species and the predator size, being kept a control treatment. An aquarium (2 L containing one larvae of Odonate and 10 larvae of fish were considered an experimental unit. After the beginning, each three hours (18:00, 21:00, 0:00, 3:00, 6:00, 9:00, 12:00, 15:00 and 18:00h, the remnant larvae of fish (alive in each experimental unit was quantified, and we replaced the consumed larvae

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.

Mercury exposure in the freshwater tilapia Oreochromis niloticus

Energy Technology Data Exchange (ETDEWEB)

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

2010-08-15

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

Mercury exposure in the freshwater tilapia Oreochromis niloticus

International Nuclear Information System (INIS)

Wang Rui; Wong Minghung; Wang Wenxiong

2010-01-01

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

Low water conductivity increases the effects of copper on the serum parameters in fish (Oreochromis niloticus).

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Canli, Esin G; Canli, Mustafa

2015-03-01

The conductivity is largely determined by ion levels in water, predominant ion being Ca(2+) in the freshwaters. For this reason, the effects of copper were evaluated as a matter of conductivity of exposure media in the present study. Thus, freshwater fish Oreochromis niloticus were exposed to copper in differing conductivities (77, 163 and 330 μS/cm), using acute (0.3 μM, 3 d) and chronic (0.03 μM, 30 d) exposure protocols. Following the exposure serum parameters of fish were measured. Data showed that there was no significant alteration (P>0.05) in serum parameters of control fish. However, activities of ALP, ALT and AST decreased significantly at the lower conductivities in chronic copper exposure, but not in acute ones. Protein levels did not differ significantly in any of the exposure conditions. However, Cu exposure at the lowest conductivity sharply increased the levels of glucose in the acute exposure, while there was no significant difference in the chronic exposure. Cholesterol levels decreased only at the lower conductivities in chronic exposure, but increased in acute exposure. Similarly, triglyceride levels increased in acute exposures and decreased in chronic exposures at the lowest conductivity. There was no change in Na(+) levels, while there was an increase in K(+) levels and a decrease in Ca(2+) level at the lowest conductivity of acute exposures. However, Cl(-) levels generally decreased at the higher conductivities of chronic exposures. There was a strong negative relationship between significant altered serum parameters and water conductivity. In conclusion, this study showed that copper exposure of fish at lower conductivities caused more toxicities, indicating the protective effect of calcium ions against copper toxicity. Data suggest that conductivity of water may be used in the evaluation of metal data from different waters with different chemical characteristics. Copyright © 2015 Elsevier B.V. All rights reserved.

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

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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.

Effect of Excoecaria agallocha on non-specific immune responses and disease resistance of Oreochromis niloticus against Streptococcus agalactiae.

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Laith, A A; Mazlan, A G; Effendy, A W; Ambak, M A; Nurhafizah, W W I; Alia, A S; Jabar, A; Najiah, M

2017-06-01

The current study was designed to evaluate the effects of Excoecaria agallocha leaf extracts on immune mechanisms and resistance of tilapia, Oreochromis niloticus, after challenge with Streptococcus agalactiae. Fish were divided into 6 groups; groups 1-5 fed with E. agallocha leaf extracts at 10, 20, 30, 40 and 50mgkg -1 level, respectively. Group 6 were fed without extract addition and acted as control. E. agallocha extracts were administered as feed supplement in fish diet for 28days and the hematological, immunological, and growth performance studies were conducted. Fish were infected with S. agalactiae at a dose of 15×105CFUmL -1 and the total white blood cell (WBC), phagocytosis and respiratory burst activities of leukocytes, serum bactericidal activity, lysozyme, total protein, albumin, and globulin levels were monitored and mortalities recorded for 15days post infection. Results revealed that feeding O. niloticus with 50mgkg -1 of E. agallocha enhanced WBC, phagocytic, respiratory burst, serum bactericidal and lysozyme activities on day 28 pre-challenge and on 3rd, 6th, 9th, 12th and 15th day post-challenge as compared to control. Total protein and albumin were not enhanced by E. agallocha diet. E. agallocha increased the survival of fish after challenge with S. agalactiae. The highest mortality rate (97%) was observed in control fish and the lowest mortality (27%) was observed with group fed with 50mgkg -1 extract. The results indicate that dietary intake of E. agallocha methanolic leaf extract in O. niloticus enhances the non-specific immunity and disease resistance against S. agalactiae pathogen. Copyright © 2017. Published by Elsevier Ltd.

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

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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.

Characterization of the microbiota of the skin and oral cavity of Oreochromis niloticusCaracterização da microbiota da pele e cavidade oral de Oreochromis niloticusdoi:10.12662/2317-3076jhbs.v4i3.767.p193-197.2016

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Edmar Maciel Lima Junior

2016-09-01

Full Text Available Introduction: Fish are usually exposed to higher microbial loads than land or air animals. The microbiota of fish mostly consists of Pseudomonas spp., Aeromonas spp., Shewanella putrefasciens, Acinetobacter spp. and Moraxella spp. The objective of this study was to analyze the oral cavity, and skin tissue microbiota on the Nile tilapia (Oreochromis niloticus, a fish species raised commercially in Brazil. Methods: Samples were collected from the oral cavity and skin of 20 Nile tilapia specimens (Oreochromis niloticus, each weighing approximately 1,000 grams. The samples were cultures for quantitative analysis on sheep blood agar (SBA and chromID™ CPS® agar (CPS. Results: Eleven different bacterial species were identified on CPS and SBA plates. Gram-negative species were the most prevalent, while gram-positive Globicatella spp, Streptococcus spp and Enterococcus faecalis were also found. Pseudomonas aeruginosa species were isolated from all samples. Gram-positive Enterococcus faecalis was found in 70 and 60% of the skin and oral samples, respectively. Conclusion: For all samples studied, the microbial load was less than 100,000 CFU/g of tissue. This value is a cutoff standardized for the American Society of Microbiology to differentiate the causal agent from the colonizers. In light of this result and considering the absence of infectious signs in the fish samples, we conclude that the CFU values found in this study reflect a normal, non-infectious colonization/microbiota.

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.

Anti-androgenic activities of diuron and its metabolites in male Nile tilapia (Oreochromis niloticus).

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Pereira, Thiago Scremin Boscolo; Boscolo, Camila Nomura Pereira; Silva, Danilo Grünig Humberto da; Batlouni, Sergio Ricardo; Schlenk, Daniel; Almeida, Eduardo Alves de

2015-07-01

Diuron (3-(3,4-dichlorophenyl)-1,1-dimethylurea) is a widely used herbicide which has been frequently detected in surface waters throughout the world. In vivo bioassay guided fractionation studies indicated that diuron may have estrogenic activity augmented by biotransformation. This study evaluated the effects of diuron and three of its metabolites on plasma hormone concentrations and spermatogenesis of the freshwater fish Nile tilapia (Oreochromis niloticus). Sexually mature male fish were exposed for 25 days to diuron, as well to its metabolites 3,4-dichloroaniline (DCA), 3,4-dichlorophenylurea (DCPU) and 3,4-dichlorophenyl-N-methylurea (DCPMU), at concentrations of 200ng/L. Testosterone levels were decreased by diuron, but had limited effects on gonadal histology. Diuron metabolites, however, caused significant decreases in testosterone and in 11-ketotestosterone, gonadosomatic index, diameter of seminiferous tubules and in the mean percentages of germ cells (spermatids and spermatozoa). We conclude that these metabolites have antiandrogenic activity to male Nile tilapia, potentially causing reproductive impairment in male fish. Copyright © 2015 Elsevier B.V. All rights reserved.

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

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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.

Effects of a saponin fraction extracted from Trigonella foenum-graecum L. and two commercially available saponins on sex ratio and gonad histology of Nile tilapa fry, Oreochromis niloticus (L.)

OpenAIRE

Stadtlander, T.; Levavi-Sivan, B.; Kerem, Z.; Dweik, H.; Qutob, M.; Abu-Lafi, S.; Francis, G.; Focken, U.; Becker, K.

2013-01-01

Over three million tonnes (t) of tilapia, mostly Nile tilapia (Oreochromis niloticus, L.), are produced annually making it the second most abundantly produced freshwater fish (FAO, 2010). Tilapia are mouthbreeders that often produce stunted populations under pond conditions; one means of prevention is to produce all-male fish with the additional advantage that males usually grow faster than females. All-male populations can be achieved by supplementing feed with androgens such as 17-α-Methylt...

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

Bioaccumulation of some heavy metals in adult tilapia oreochromis niloticus in Southern part of Laguna de Bay

International Nuclear Information System (INIS)

Sandoval, Kristine L.; Padua, Haizelle O.; De Jesus, Editha E.; Enal, Maria Luisa A.

2010-01-01

Tilapia, Oreochromis niloticus, one of the most important fish species in Philippine aquaculture, is grown abundantly in Laguna de Bay. A preliminary study was conducted to determine the levels of accumulated mercury (Hg), cadmium (Cd) and lead (Pb) in the muscle tissue of this fresh water fish collected from February (wet season) to March (dry season) 2008 in the southern part of Laguna de Bay. Heavy metal analyses using atomic absorption spectrophotometer (AAS) showed a higher concentration of Hg and Cd during the wet season than in the dry season. However, analysis of variance revealed significant seasonal variation on only in Cd (P=0.0253). Lead, on the other hand, was not detected in the fish samples. The mean concentration set by FAO but the mean level of Cd (0.161 ppm) was almost equal to the limit given for fish. This could represent a significant health risk to the consuming public. (author)

Genetic parameters for reproductive traits in female Nile tilapia (Oreochromis niloticus): II. Fecundity and fertility

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

2013-01-01

Harvest weight is the main trait in Nile tilapia (Oreochromis niloticus) breeding programmes. The effects of selection for harvest weight on female reproductive traits are unknown. In this paper we estimate genetic parameters for reproductive traits and their correlation with harvest weight using

Effects of Microcystis on Hypothalamic-Pituitary-Gonadal-Liver Axis in Nile Tilapia (Oreochromis niloticus).

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Chen, Jiazhang; Meng, Shunlong; Xu, Hai; Zhang, Zhen; Wu, Xiangyang

2017-04-01

In the present study, Nile tilapia (Oreochromis niloticus) were used to assess the endocrine disruption potential of Microcytis aeruginosa. Male Nile tilapia were exposed to lyophilized M. aeruginosa or purified microcystin-LR (8.3 μg/L) for 28 days. The levels of serum hormones (17β-estradiol and testosterone) and transcripts of selected genes in the hypothalamus-pituitary-gonadal-liver axis were analyzed. The results showed that serum hormones were significantly up-regulated, and transcripts of 13 genes (GHRH, PACAP, GH, GHR1, GHR2, IGF1, IGF2, CYP19a, CYP19b, 3β-HSD1, 20β-HSD, 17β-HSD1 and 17β-HSD8) were significantly altered after Microcytis exposure. These results indicate that fish reproduction can be altered in a Microcystis bloom-contaminated aquatic environment.

Growth of Nile tilapia Oreochromis niloticus fed with different levels of alcohol yeast.

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Medri, V; Pereira, G V; Leonhardt, J H

2000-02-01

Two hundred and forty 45-day-old fingerlings of Nile tilapia (Oreochromis niloticus), sexually reverted with an initial average weight of 1.25 +/- 0.14 g, distributed in a totally casualized delineation, during 330 days. The effect of the substitution of 10%, 20% and 30% of the ration by distillery yeast (Saccharomiyces cerevisae) in balanced experimental rations on the development in the breeding of tilapias did not show a harmful effect up to the maximum tested level of 30%, showing that the choice of the yeast in the ration for these fishes depends on the availability and occasional cost. The yeast provides fish with good resistance to unfavorable environmental conditions, which could be verified since there were no statistical differences among the treatments with different levels of yeast and the witness. The long growth rate in terms of length and weight can be attributed to the little available space for each specimen, not obeying the limit of populational density, as well as reduction of food ingestion, which coincide with the winter season, above of the absence of natural feeding.

Effect of Poly Aluminium Chloride (PAC) on some blood constituents of Nile Tilapia (Oreochromis niloticus)

International Nuclear Information System (INIS)

Adam, H. M.; Agab, H.

2006-01-01

Poly aluminium chloride (PAC) is an urban drinking water purification substance that was introduced recently in Sudan and used to substitute polymer poly diallyl dimethyl aluminium chloride (DADMAC) and aluminium sulphate in water purification treatments. This study was conducted to determine its effects on fish health, which is is considered a biological indicator and an essential component of fresh water ecosystem. In this experiment, PAC was used in three different concentrations (0.1, 0.2 and 0.3 ml/1) in experimental tanks to achieve the desirable doses for the study. The tanks were populated by Nile Tilapia fingerlings (Oreochromis niloticus) with an average weight ranging between 70 and 100 grams. Exposure of this fish to PAC resulted in an immediate signification reduction (P<0.01) in haemoglobin concentration, erythrocytes count, packed cell volume, mean corpuscular volume and mean corpuscular haemoglobin concentration of experimental fingerlings blood. The degree of reduction in these parameters was directly proportional to the concentration of PAC used. (Author)

Effects of thermal treatments during cooking, microwave oven and boiling, on the unconjugated microcystin concentration in muscle of fish (Oreochromis niloticus).

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Guzmán-Guillén, Remedios; Prieto, Ana I; Moreno, Isabel; Soria, Ma Eugenia; Cameán, Ana M

2011-09-01

Understanding the factors that contribute to the risk from fish consumption is a relevant public health concern due to potential adverse effects of cyanobacterial toxins. The aim of this work was to study the influence of two usual cooking practices, microwave oven and boiling, on the microcystin (MCs) concentration in fish muscle (Tilapia, Oreochromis niloticus) spiked with a stock solution (500 μL) containing a mixture of three toxins (MC-LR, MC-RR, and MC-YR) (1.5 μg/mL of each toxin). Two different variables were investigated: time of cooking in the microwaves treatment (1 or 5 min), and way of boiling, "boiled muscle" or "continuously heated muscle". All samples were then lyophilized and MCs were extracted and purified (Oasis HLB cartridge) and quantified by HPLC-MS. Furthermore, the waters in which the samples boiled were also analyzed after their purification. The results suggest a reduction on MC-LR (36%) and MC-YR (24.6%) in samples cooked in the microwave for 5 min. Major changes were found when the fish was cooked by the continuous boiling, with a decrease of 45.0% (MC-RR), 56.4% (MC-YR) and 59.3% (MC-LR). More studies are necessary to elucidate the mechanisms involved when aquatic food is submitted to usual cooking practices. Copyright © 2011 Elsevier Ltd. All rights reserved.

Comportamento alimentar da tilápia do Nilo (Oreochromis niloticus frente a diferentes ingredientes alimentares Alimentary ingredients and the feeding behavior of Nile tilápia (Oreochromis niloticus

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Elyara Maria Pereira-da-Silva

1999-07-01

Full Text Available Foram avaliadas as respostas comportamentais da tilápia do Nilo (Oreochromis niloticus frente a 14 ingredientes utilizados na alimentação de peixes: farinhas de carne, de peixe, de crisálidas, de camarão, de girassol, de algodão e de mandioca, ovo integral liofilizado, levedura de cana-de-açúcar, farelos de soja e de trigo, glúten de milho, fubá de milho e raspa de mandioca. O método utilizado foi de dupla escolha, comparando-se cada ingrediente peletizado a uma ração denominada controle. Foram empregados quatro aquários (750 litros, contendo, cada um, três alevinos e dois comedouros instalados nos cantos direito e esquerdo, sendo registradas as respostas dos animais para cada ingrediente, separadamente. Concluiu-se que as respostas comportamentais da tilápia variam de acordo com o ingrediente oferecido e que parece existir uma correlação positiva entre o grau de atrato-palatabilidade de um ingrediente e a ocorrência de confrontos agonísticos entre os indivíduos. Sugere-se que ingredientes classificados como de alta atrato-palatabilidade (farinhas de crisálidas, de peixe, de carne, de camarão e ovo liofilizado integral sejam adicionados às dietas especiais para peixes, visando ao aumento da ingestão alimentar nos períodos pré-invernais, situações de estresse ou estados patológicos.Nile Tilapia (Oreochromis niloticus responses to attractivity and taste of fourteen food ingredients, here classified as animal sources (shrimp, fish, silkworm and meat meal, integral lyophilized egg and sugar-cane-yeast, vegetable protein sources (maize gluten, soybean bran, sunflower meal and cotton bran and energetics (maize flour, manioc scraping, manioc bran and wheat bran were investigated. These ingredients were compared to a control diet, using a two-choice method. Four 750 liters aquaria stocked with three fries each and two feeders installed respectively at the right and left corner where used to register the responses of the

Antioxidant activities of red tilapia (Oreochromis niloticus) protein hydrolysates as influenced by thermolysin and alcalase

Science.gov (United States)

Daud, Nur'Aliah; Babji, Abdul Salam; Yusop, Salma Mohamad

2013-11-01

The hydrolysis process was performed on fish meat from Red Tilapia (Oreochromis niloticus) by enzymes thermolysin and alcalase under optimum conditions. The hydrolysis was performed from 0 - 4 hours at 37°C. Hydrolysates after 2 hours incubation with thermolysin and alcalase had degree of hydrolysis of 76.29 % and 63.49 %, respectively. The freeze dried protein hydrolysate was tested for peptide content and characterized with respect to amino acid composition. The result of increased peptide content in Red Tilapia (O. Niloticus) hydrolysates obtained was directly proportional to the increase activities of different proteolytic enzymes. The result of amino acid composition showed that the sample used contained abundant Gly, Ala, Asp, Glu, Lys and Leu in residues or peptide sequences. Both enzymatic hydrolysates were tested for anti-oxidant activity with DPPH and ABTS assay. Alcalase yielded higher anti-oxidative activity than Thermolysin hydrolysates after 1 hour incubation, but both enzymes hydrolysates showed a significant decrease of anti-oxidant activity after 2 hours of incubation. Hydrolysates from Red Tilapia may contribute as a health promoting ingredient in functional foods to reduce oxidation stress caused by accumulated free radicals.

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

Eubiotic effect of a dietary acidifier (potassium diformate on the health status of cultured Oreochromis niloticus

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Nermeen M. Abu Elala

2015-07-01

Full Text Available In connection with the global demand for safe human food and the production of environmentally friendly aquaculture products, acidifiers are natural organic acids and salts that have received considerable attention as animal-feed additives. The current study was designed to evaluate the effects of potassium diformate (KDF on the growth performance and immunity of cultured Oreochromis niloticus (O. niloticus. Four iso-nitrogenous and iso-caloric rations containing graded levels of KDF, including 0% (control basal diet, 0.1%, 0.2% and 0.3%, were fed separately to four equal fish groups (30 fish/group with an initial body weight of 53.49 ± 6.15 g for sixty days. At the end of the experimental period, the fish groups fed on 0.2% and 0.3% KDF exhibited significant improvements in their feed intake, live weight gain, specific growth rate, feed conversion ratio and protein efficiency ratio, with concomitant improvement of their apparent protein digestibility (p < 0.05. Dietary supplementation of 0.3% KDF appeared to stimulate the beneficial intestinal flora; a proliferation was observed of indigenous probionts (Eubiosis associated with the relative activation of cellular and humeral innate immunity (phagocytic activity/index, nitroblue tetrazolium reduction test and serum/gut mucous lysozyme activity. The cumulative mortality of the fish groups fed on KDF and challenged orally with Aeromonas hydrophila was lower than that of the control group. The resistance against diseases increased with dietary KDF in a dose-dependent manner. Thus, we conclude that the use of acidifiers can be an efficient tool to achieve sustainable, economical and safe fish production.

Beta-haemolytic streptococci in farmed Nile tilapia, Oreochromis niloticus, from Sullana-Piura, Peru

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Yessica Ortega A

2017-01-01

Full Text Available Objective. This investigation aimed to study the presence of Streptococcus spp. in tilapia (Oreochromis niloticus from fish farm located in Sullana-Piura, Peru. Materials and methods. 150 fish with clinical signs of streptococcal disease were sampled, and the bacterium isolation was performed on blood agar, correlated to histopathological lesions description and molecular confirmation by real-time PCR. Results. The necropsy revealed exophthalmia, hyphema, congestion and/or haemorrhagic meninges, ascites, splenomegaly, hepatomegaly and diffuse haemorrhagic zones throughout the body. 102 isolated positives (54 tilapias to Streptococcus spp. were identified in the microbiological analysis (prevalence of 26%, the brain was the organ with the highest percentage of this bacteria (34.31%, and 19 isolates were beta-haemolytic (18.63% with prevalence of 10.12%. Fish beta-haemolytic streptococci presented epicarditis, perisplenitis and chronic meningitis, panophthalmitis, coagulative necrosis of skeletal muscle and granulomas formation. In the confirmatory test by real-time PCR, any positive tilapia to S. iniae was obtained. The results were analysed using a stochastic simulation of beta distribution using @Risk program uncertainty, reporting an average prevalence of 0.66% in sick tilapias. Conclusions. The analysed fishes were positive to bacteria of the genus Streptococcus, which confirms its presence in the fish farm. However, 19 isolates were beta-haemolytic, and the presence of S. iniae was not positive to the limit prevalence of 2.7% in real-time PCR.

Studies and Observations on the Spawning of Oreochromis Niloticus Species Reared at SCDP Nucet - Dambovita

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Cecilia Bucur

2012-10-01

Full Text Available At the Fish Culture Research and Development Station Nucet, in 2011 were achieved studies and observations on the reproduction, sexual organs and seminal products of Oreochromis niloticus tropical species. A batch of 140 breeders of 1 year old Nile tilapia (T1 was stoked both in a pond as in Ewos tanks in two variants of density (VI – 8 fish/tank, (VII – 12 fish/tank. In a third variant were used 2 years old Nile tilapia breeders (T2, (VIII – 4 fish/tank. The male/female ratio in all variants from tanks was 1:3. Independently, into another tank were stoked 20 males. Into the pond, spawning was achieved naturally, and on the tank variants, the eggs were gathered from the mouth of females and incubated in different incubation systems. On both rearing systems, under the climatic conditions from Nucet (south of Romania were achieved 3 generations of Nile tilapia fry. On the female breeders, were determined: the gonad-somatic ratio, theoretical and adjective prolificacy (no. of eggs/g of ovary, and for males were achieved spermatozoa motility tests and determination of spermatozoa number per unit of volume.

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

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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

Effects of Dietary Yeast (Saccharomyces cerevisia Supplementation in Practical Diets of Tilapia (Oreochromis niloticus

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José E. P. Cyrino

2012-01-01

Full Text Available A 51-day feeding trial was carried out to determine the effects of various dietary levels of brewer’s yeast, Saccharomyces cerevisiae, in the growth performance, body composition and nutrient utilization in Nile tilapia, Oreochromis niloticus, juveniles. Fish (7.6 ± 0.3 g were stocked into eighteen 1,000-L tanks (100 fish per tank; n = 3 and fed to apparent satiation six isonitrogenous (27% crude protein and isoenergetic (19 kJ/g diets, formulated to contain different dried yeast levels (0%, 10%, 15%, 20%, 30% or 40% diet in substitution to fishmeal. Body weight tripled at the end of the feeding trial for fish fed up to 20% dietary yeast incorporation. Daily growth coefficient (DGC, % body weight/day decreased with increasing dietary yeast level (P < 0.0001. Voluntary feed intake (VFI, %BW/day did not vary significantly with increasing yeast level. Fish fed 40% yeast showed significant reduction in protein efficiency rate, protein retention and nitrogen gain. Increasing levels of dietary yeast did not significantly affect protein or lipid digestibility. Dietary dried yeast was seemingly palatable to tilapia juveniles and was suitable up to 15% inclusion to promote growth and efficient diet utilization, without affecting body composition.

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

Full Text Available Em três experimentos, testou-se a eficiência do mentol como anestésico para a tilápia-do-nilo (Oreochromis niloticus, por meio da avaliação de eventos comportamentais, da verificação da margem de segurança do anestésico e das respostas de estresse. No primeiro experimento, foram testadas seis diferentes concentrações de mentol para avaliar o tempo de indução à anestesia. No segundo, foram realizados dois testes com o objetivo de verificar a margem de segurança do anestésico. No terceiro, avaliou-se o efeito estressante do anestésico. A concentração 250mg L-1 de mentol foi a mais adequada para indução de anestesia cirúrgica. Para anestesia voltada para biometria e breve inspeção visual do animal, a concentração mais adequada foi 150-200mg L-1. O dobro da concentração ideal (500mg L-1 não acarretou a morte nos indivíduos, indicando boa margem de segurança para o uso desse anestésico. O mentol, mesmo em sua concentração adequada, induziu ao aumento na glicose sanguínea, caracterizando estresse no peixe. Conclui-se que o mentol não é um anestésico eficaz para juvenis de tilápia durante procedimentos de rotina na piscicultura.This work tested the effectiveness of menthol as anesthetic for Nile tilápia (Oreochromis niloticus by the evaluation of behavioral events, the safety margin of the anesthetic, and stress response. On first experiment, six different anesthetic concentrations were tested to evaluate the induction time to anesthesia. On second experiment, two tests were carried out to verify the safety margin of the anesthetic. On third experiment, stress responses were evaluated. The safe concentration to induce a surgical anesthesia was 250mg L-1. To a brief handling and visual inspection, the appropriated concentration was 150-200mg L-1. There was no mortality after exposure to 500mg L-1, indicating a good safety margin for this anesthetic. Menthol even in its adequate dosage induced a rise in glucose

First report of Streptococcus agalactiae isolated from Oreochromis niloticus in Piura, Peru: Molecular identification and histopathological lesions

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Yessica Ortega Asencios

2016-11-01

Full Text Available The aim of this study was to identify the bacterium Streptococcus agalactiae isolated in farmed Nile tilapia (Oreochromis niloticus from Piura, Peru and to characterize the histopathological lesions caused by this pathogen. Sixteen tilapias were sampled with clinic signs of the disease such as erratic swimming, exophthalmia and haemorrhages on the body and fins. Qualitative PCR in real time and histopathological analysis were performed. Nine fishes positives to S. agalactiae were found. The main histopathological findings were fibrinosuppurative epicarditis, periesplenitis, meninigitis and panophtaltmitis with predominance of mononuclear infiltration in all tissues. The correlation between qPCR and histopathological findings demonstrated nine fish (prevalence of 56.25% with Cq lower than 30, associated to high degree of tissue injuries. This study reports the first isolation of S. agalactiae by PCR in real time in tilapia farmed in Peru and characterizes the major histopathological changes caused by this bacterium.

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.

Changes in the quality of fishburger produced from Tilapia ( Oreochromis niloticus ) during frozen storage (-18 degrees C)

DEFF Research Database (Denmark)

Tokur, B.; Polat, A.; Beklevik, G.

2004-01-01

In this study, the chemical and sensory qualities of fishburger produced from tilapia (Oreochromis niloticus) were investigated during frozen storage (-18 degreesC) over 8 months. The ratios of crude protein, lipid, moisture, crude ash, and polyunsaturated fatty acids in tilapiaburger were found...

Caracterización de tilapia roja (Oreochromis sp. con marcadores moleculares RAPD Characterization of the red tilapia Oreochromis sp. through molecular markers RAPD

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Julieta Torres Jaramillo

2010-04-01

Full Text Available Se utilizó la técnica RAPD (amplificación al azar de ADN polimórfico para el estudio de la diversidad genética de Oreochromis sp. (tilapia roja en cinco piscícolas del Valle del Cauca (Colombia y en la determinación del nivel de introgresión de las especies parentales Oreochromis mosambicus, O. niloticus y O. aureus. Se evaluaron 25 cebadores, ocho fueron polimórficos y se obtuvieron 109 bandas. Los valores de heterocigosidad esperada (0.196 a 0.256 y la estructura genética (Gst = 0.22 para Oreochromis sp. indicaron un elevado grado de polimorfismo y alta estructuración genética. Estos resultados fueron consistente con el Fst = 0.268 (P Random amplified polymorphic DNA (RAPD markers were used to study genetic diversity on red Tilapia (Oreochromis sp. species collected from five fish farms located in the Valle del Cauca, Colombia and to determine the level of introgression from three parental species O. mosambicus, O. niloticus and O. aureus into local Oreochromis populations. from the 25 RAPD primers evaluated, eight were polymorphic and 109 banding patterns were observed, any of them were specific. The expected levels of heterozygosis (0.1964 to 0.2561 and genetic structure (Gst = 0.22 funded for Oreochrosmis sp. indicate high grade of polymorphism and genetic structuring. This results were observed following the analysis of molecular variance [AMOVA] (Fst = 0.268 (P <0.0001 and Multiple correspondence analysis (Gst = 0.040. The values of genetic similarity, the analysis of group, the analysis of multiple correspondence and the level of introgression, indicated that the differences in the introgression levels(P=0.0001 were significant. The low level of observed genetic differentiation among populations, could be the result of fish with the same genetic origin, whereas the high variation within populations can be displayed by handling practices and the pressure of selection to favor commercial phenotypes. The level of introgression

Karyotypical characterization from stock of Nile tilapia, Oreochromis niloticus, at Londrina State University, PR, Brazil, through several techniques of chromosomes band/ Caracterização cariotípica de um estoque de tilápia do Nilo,Oreochromis niloticus, da Universidade Estadual de Londrina, mediante diversas técnicas de bandamento cromossômico

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Julio Hermann Leonhardt

2006-07-01

Full Text Available 14 specimens of Nile’s tilapia were analyzed cytogenetically, Oreochromis niloticus, that belong to the stock of fish breeding from the Freshwater Aquaculture Station of the Londrina State University in the Paraná, Brazil. All specimens presented the same disploid number of 44 chromosomes. The NORs were observed in four chromosomes with marks in terminal position of the short arm and the hybridization “in situ” (FISH with probe of 18 S also evidenced the presence of two pairs of chromosomes containing ribbosomic cistrons. The treatment with the fluochromes CMA3 and DAPI, respectively, didn’t show shinning bands in any chromosome of the complement. The band C (CBG evidenced regions of heterochromatin distributed on several chromosomes in the centromeric regions, being observed some marks in telomeric regions, mainly on the biggest pair of chromosomes of the complement, a pair presented itself almost totally heterochromatic. The obtained results are in accordance with the data found in literature, nevertheless when the C bands and NORs were analyzed, were evidenced some differences that apparently characterized the local fish population of the Londrina State University. Key words: Cytogenetics, Oreochromis niloticus, NORs, CMA3, DAPI, fish, heterochromatin.Foram analisados citogeneticamente 14 indivíduos de tilápia do Nilo, Oreochromis niloticus que fazem parte do estoque de reposição de reprodutores da Estação de Piscicultura da Universidade Estadual de Londrina, Paraná, Brasil. Todos os indivíduos apresentaram o mesmo número diplóide de 44 cromossomos. As NORs foram observadas em quatro cromossomos com marcações em posição terminal do braço curto e a hibridação “in situ” (FISH com sonda de 18S também evidenciou a presença de dois pares de cromossomos contendo cístrons ribossômicos. O tratamento com os fluorocromos CMA3 e DAPI, respectivamente, não mostrou bandas brilhantes em nenhum cromossomo do complemento. A

Thermal preference predicts animal personality in Nile tilapia Oreochromis niloticus.

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Cerqueira, Marco; Rey, Sonia; Silva, Tome; Featherstone, Zoe; Crumlish, Margaret; MacKenzie, Simon

2016-09-01

Environmental temperature gradients provide habitat structure in which fish orientate and individual thermal choice may reflect an essential integrated response to the environment. The use of subtle thermal gradients likely impacts upon specific physiological and behavioural processes reflected as a suite of traits described by animal personality. In this study, we examine the relationship between thermal choice, animal personality and the impact of infection upon this interaction. We predicted that thermal choice in Nile tilapia Oreochromis niloticus reflects distinct personality traits and that under a challenge individuals exhibit differential thermal distribution. Nile tilapia were screened following two different protocols: 1) a suite of individual behavioural tests to screen for personality and 2) thermal choice in a custom-built tank with a thermal gradient (TCH tank) ranging from 21 to 33 °C. A first set of fish were screened for behaviour and then thermal preference, and a second set were tested in the opposite fashion: thermal then behaviour. The final thermal distribution of the fish after 48 h was assessed reflecting final thermal preferendum. Additionally, fish were then challenged using a bacterial Streptococcus iniae model infection to assess the behavioural fever response of proactive and reactive fish. Results showed that individuals with preference for higher temperatures were also classified as proactive with behavioural tests and reactive contemporaries chose significantly lower water temperatures. All groups exhibited behavioural fever recovering personality-specific thermal preferences after 5 days. Our results show that thermal preference can be used as a proxy to assess personality traits in Nile tilapia and it is a central factor to understand the adaptive meaning of animal personality within a population. Importantly, response to infection by expressing behavioural fever overrides personality-related thermal choice. © 2016 The Authors

Occurrence and antibiotic susceptibility of fish bacteria isolated from Oreochromis niloticus (Nile tilapia and Clarias gariepinus (African catfish in Uganda

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S. P. Wamala

2018-02-01

Full Text Available Abstract The intention of this study was to identify the bacterial pathogens infecting Oreochromis niloticus (Nile tilapia and Clarias gariepinus (African catfish, and to establish the antibiotic susceptibility of fish bacteria in Uganda. A total of 288 fish samples from 40 fish farms (ponds, cages, and tanks and 8 wild water sites were aseptically collected and bacteria isolated from the head kidney, liver, brain and spleen. The isolates were identified by their morphological characteristics, conventional biochemical tests and Analytical Profile Index test kits. Antibiotic susceptibility of selected bacteria was determined by the Kirby-Bauer disc diffusion method. The following well-known fish pathogens were identified at a farm prevalence of; Aeromonas hydrophila (43.8%, Aeromonas sobria (20.8%, Edwardsiella tarda (8.3%, Flavobacterium spp. (4.2% and Streptococcus spp. (6.3%. Other bacteria with varying significance as fish pathogens were also identified including Plesiomonas shigelloides (25.0%, Chryseobacterium indoligenes (12.5%, Pseudomonas fluorescens (10.4%, Pseudomonas aeruginosa (4.2%, Pseudomonas stutzeri (2.1%, Vibrio cholerae (10.4%, Proteus spp. (6.3%, Citrobacter spp. (4.2%, Klebsiella spp. (4.2% Serratia marcescens (4.2%, Burkholderia cepacia (2.1%, Comamonas testosteroni (8.3% and Ralstonia picketti (2.1%. Aeromonas spp., Edwardsiella tarda and Streptococcus spp. were commonly isolated from diseased fish. Aeromonas spp. (n = 82 and Plesiomonas shigelloides (n = 73 were evaluated for antibiotic susceptibility. All isolates tested were susceptible to at-least ten (10 of the fourteen antibiotics evaluated. High levels of resistance were however expressed by all isolates to penicillin, oxacillin and ampicillin. This observed resistance is most probably intrinsic to those bacteria, suggesting minimal levels of acquired antibiotic resistance in fish bacteria from the study area. To our knowledge, this is the first study to

Reproductive performance of female Nile tilapia ( Oreochromis niloticus fed diets with different digestible energy levels

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Tamira Maria Orlando

Full Text Available ABSTRACT This study aimed to evaluate the reproductive performance of female Nile tilapia (Oreochromis niloticus fed diets containing different levels of digestible energy (DE. The fish were housed in 15 fiberglass tanks (500 L in a recirculating system at an average temperature of 27.5 °C. The treatments consisted of five diets with increasing levels of DE (3,200; 3,400; 3,600; 3,800; and 4,000 kcal/kg. The levels of DE did not significantly influence the final weight or the hepatosomatic, gonadosomatic, and visceral fat indices. The absolute fecundity was influenced by the treatments, for which the highest values were observed from the 3,600 kcal/kg DE level and upward. The proximate composition of the fish also had a significant effect on the variables crude protein, ether extract, and ash; the fish fed diets with higher levels of DE exhibited the lowest body protein content, while the accumulation of ether extract exhibited the opposite response. A level of 3,600 kcal/kg of digestible energy should be used in diets with 380 g/kg crude protein and a starch/lipid ratio of 1.33 for female Nile tilapia.

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.

Blockage of progestin physiology disrupts ovarian differentiation in XX Nile tilapia (Oreochromis niloticus)

International Nuclear Information System (INIS)

Zhou, Linyan; Luo, Feng; Fang, Xuelian; Charkraborty, Tapas; Wu, Limin; Wei, Jing; Wang, Deshou

2016-01-01

Previous studies indicated that maturation inducing hormone, 17α, 20β-Dihydroxy-4-pregnen-3-one (DHP), probably through nuclear progestin receptor (Pgr), might be involved in spermatogenesis and oogenesis in fish. To further elucidate DHP actions in teleostean ovarian differentiation, we analyzed the expression of pgr in the ovary of Nile tilapia (Oreochromis niloticus), and performed RU486 (a synthetic Pgr antagonist) treatment in XX fish from 5 days after hatching (dah) to 120dah. Tilapia Pgr was abundantly expressed in the follicular cells surrounding oocytes at 30 and 90dah. Continuous RU486 treatment led to the blockage of oogenesis and masculinization of somatic cells in XX fish. Termination of RU486 treatment and maintenance in normal condition resulted in testicular differentiation, and estrogen compensation in RU486-treated XX fish successfully restored oogenesis. In RU486-treated XX fish, transcript levels of female dominant genes were significantly reduced, while male-biased genes were evidently augmented. Meanwhile, both germ cell mitotic and meiotic markers were substantially reduced. Consistently, estrogen production levels were significantly declined in RU486-treated XX fish. Taken together, our data further proved that DHP, possibly through Pgr, might be essential in the ovarian differentiation and estrogen production in fish. - Highlights: • DHP plays a critical role in early stage oogenesis of XX tilapia. • Blockage of DHP actions by RU486 treatment led to masculinization and/or sex reversal in XX tilapia. • Both DHP and estrogen are indispensable for ovarian differentiation.

Blockage of progestin physiology disrupts ovarian differentiation in XX Nile tilapia (Oreochromis niloticus)

Energy Technology Data Exchange (ETDEWEB)

Zhou, Linyan; Luo, Feng; Fang, Xuelian [Key Laboratory of Freshwater Fish Reproduction and Development (Ministry of Education), Key Laboratory of Aquatic Science of Chongqing, School of Life Sciences, Southwest University, Chongqing, 400715 (China); Charkraborty, Tapas [South Ehime Fisheries Research Center, Ehime University, Ainan, 798-4206 (Japan); Wu, Limin; Wei, Jing [Key Laboratory of Freshwater Fish Reproduction and Development (Ministry of Education), Key Laboratory of Aquatic Science of Chongqing, School of Life Sciences, Southwest University, Chongqing, 400715 (China); Wang, Deshou, E-mail: wdeshou@swu.edu.cn [Key Laboratory of Freshwater Fish Reproduction and Development (Ministry of Education), Key Laboratory of Aquatic Science of Chongqing, School of Life Sciences, Southwest University, Chongqing, 400715 (China)

2016-04-22

Previous studies indicated that maturation inducing hormone, 17α, 20β-Dihydroxy-4-pregnen-3-one (DHP), probably through nuclear progestin receptor (Pgr), might be involved in spermatogenesis and oogenesis in fish. To further elucidate DHP actions in teleostean ovarian differentiation, we analyzed the expression of pgr in the ovary of Nile tilapia (Oreochromis niloticus), and performed RU486 (a synthetic Pgr antagonist) treatment in XX fish from 5 days after hatching (dah) to 120dah. Tilapia Pgr was abundantly expressed in the follicular cells surrounding oocytes at 30 and 90dah. Continuous RU486 treatment led to the blockage of oogenesis and masculinization of somatic cells in XX fish. Termination of RU486 treatment and maintenance in normal condition resulted in testicular differentiation, and estrogen compensation in RU486-treated XX fish successfully restored oogenesis. In RU486-treated XX fish, transcript levels of female dominant genes were significantly reduced, while male-biased genes were evidently augmented. Meanwhile, both germ cell mitotic and meiotic markers were substantially reduced. Consistently, estrogen production levels were significantly declined in RU486-treated XX fish. Taken together, our data further proved that DHP, possibly through Pgr, might be essential in the ovarian differentiation and estrogen production in fish. - Highlights: • DHP plays a critical role in early stage oogenesis of XX tilapia. • Blockage of DHP actions by RU486 treatment led to masculinization and/or sex reversal in XX tilapia. • Both DHP and estrogen are indispensable for ovarian differentiation.

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.

Hybridisation between native Oreochromis species and introduced ...

African Journals Online (AJOL)

The Nile tilapia Oreochromis niloticus has been introduced throughout Africa outside its native range for aquaculture purposes. Hybridisation between escaped O. niloticus and native Oreochromis species is of concern due to potential negative effects on wild genetic resources for conservation, aquaculture and capture ...

Edad y crecimiento del híbrido de tilapia Oreochromis niloticus x Oreochromis aureus (Perciformes: Cichlidae) en la represa “Zimapán” Hidalgo, México

OpenAIRE

M. A. Gómez-Ponce; K. Granados-Flores; C. Padilla; M. López-Hernández; G. Núñez-Nogueira

2011-01-01

La edad y crecimiento de la tilapia Oreochromis niloticus x Oreochromis aureus fueron determinados por medio de la lectura de escamas. Un total de 382 individuos fueron capturados mediante el uso de redes agalleras y atarrayas. Ocho recolectas mensuales se llevaron a cabo entre septiembre 2003-mayo 2004; se registraron los datos de longitud estándar en cm. (Le), el peso total en g (Pt) y se obtuvieron muestras de escamas para registrar el largo de la escama en mm. (Lesc) y el número de anillo...

Bioactivity of crude ethanol extract and fractions of Eugenia uniflora (Myrtaceae) in the hepatopancreas of Oreochromis niloticus L.

Science.gov (United States)

Fiuza, Tatiana S; Silva, Paulo C; De Paula, José R; Tresvenzol, Leonice M F; Sabóia-Morais, Simone M T

2009-01-01

This study evaluates the bioactivity of the crude ethanol extract and ethyl acetate, hexane and chloroform fractions obtained from Eugenia uniflora leaves using the hepatopancreas of Oreochromis niloticus L. as an experimental model. The ethanol extract and fractions were administered to the fish orally with their feed. Twenty-four hours later, the fish were sacrificed and their livers dissected, fixed in neutral formalin, embedded in paraffin and sectioned. Histological analyses were performed using Masson's trichrome and Haematoxylin-Eosin. Histochemical studies were performed using Feulgen, PAS (Periodic Acid Schiff) and PAS + salivary amylase and Sudan IV stain. The qualitative analysis of the material showed that the crude extract and the ethyl, chloroform and hexane fractions induced vasodilation, vascular congestion and toxicity due to the presence of eosinophilic granular cells, rodlet cells, some leukocytic infiltrate and rare focal necroses. The Nile tilapia proved to be a satisfactory model for screening plant products.

Changes of Microbiological Quality in Aquaculture tilapia (Oreochromis niloticus) After Irradiation Treatment

International Nuclear Information System (INIS)

Ali, H.A.S.

2015-01-01

The effect of different doses of gamma irradiation (1, 3 and 5 kGy) on the microbial flora of aquacultured Nile tilapia fish (Oreochromis niloticus) in cages inserted in Manzala Lake, Egypt, was investigated. These fish were fed on poultry by-product meal (PBM) in practical diets as replacement for fish meal protein in which herring fish meal (HFM) were replaced by PBM at ratio of 25 %, 50 %, 75% and 100% in the diet. Based on the results, it could be noticed that there was non-significant effect after partial (25, 50 and 75%) and complete replacement of fish meal protein by poultry by-product meal on the total bacterial count TBC, mould and yeast and Staphylococcus aureus counts (log cfu/g) of tilapia fish. Significant increases in the counts of Escherichia coli, Enterobacteriaceae and Enterobacter aerogenes were recorded, specially at the high levels of replacement (75 and 100%). Concerning the effect of gamma irradiation on fish samples, it could be observed that gamma irradiation with the doses 1,3 and 5 kGy significantly reduced TBC, mould and yeast, S. aureus. E. coli, Enterobacter aerogenes and Enterobacteriaceae counts of all treatments which reached undetectable values by using gamma irradiation doses of 3 and 5 kGy. From the present results, it could be concluded that using poultry by-product meal (PBM) in diets for Nile tilapia as replacement for fish meal protein supplied by herring fish meal (HFM) in the diet (to reduce feeding economic cost) significantly increase the log count of Enterobacteriaceae, Escherichia coli and Enterobacter aerogenes. However using gamma irradiation significantly reduced these counts which were undetectable using 3 and 5 kGy. It could be concluded that using gamma irradiation with dose 3 kGy can improve the hygienic quality of aquacultured Nile tilapia.

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

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A.L.S. Castro

2009-04-01

Full Text Available 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 < 0.05, two-way ANOVA with LSD post hoc test, induced spawning in females (3 spawning in V and also 3 in Ch+V condition, and increased GSI in males (mean ± SEM; V: 1.39 ± 0.08, Ch+V: 1.21 ± 0.08, Ch: 1.04 ± 0.07, Iso: 0.82 ± 0.07%; P < 0.05, two-way ANOVA with LSD post hoc test. Chemical 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.

Hematological and biochemical characters of monosex tilapia (Oreochromis niloticus, Linnaeus, 1758 cultivated using methyltestosterone

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Alaa El-Din H. Sayed

2015-10-01

Full Text Available The use of steroid-treated feeds as 17 α-methyltestosterone for the production of all-male populations is widespread in tilapia aquaculture. The aim of the present study was to investigate the misuse effects of methyltestosterone on monosex farmed Nile tilapia, Oreochromis niloticus by evaluation of hematological and biochemical values. The fishes were obtained from four localities (Assiut as a control, Beheira, Alexandria and Kafr el-Sheikh: three farms from each governorate as farmed monosex produced using methyltestosterone. The total erythrocyte count, hemoglobin rate, hematocrit percentage, mean corpuscular hemoglobin (MCH, mean corpuscular hemoglobin concentration (MCHC, mean corpuscular volume (MCV, white blood cell count, blood platelets, lymphocyte, monocyte, neutrophils and basophils were determined. The results showed that there were changes in the erythrocytic series and in the defense white blood cells. Activities of aspartate aminotransferase (AST, alanine aminotransferase (ALT and alkaline phosphatase (ALP, glucose, cholesterol, total protein, uric acid and creatinine were determined for biochemical study. These alterations are considered an indication for performance and health of fish in the monosex culture medium indicating the side effects of overdose induction of MT.

Depletion of florfenicol amine, marker residue of florfenicol, from the edible fillet of tilapia (Oreochromis niloticus x O. niloticus and O. niloticus x O. aureus) following florfenicol administration in feed

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Gaikowski, M.P.; Mushtaq, M.; Cassidy, P.; Meinertz, J.R.; Schleis, S.M.; Sweeney, D.; Endris, R.G.

2010-01-01

Aquaflor??, a 50% feed premix containing the broad spectrum antibacterial agent florfenicol is available globally to control mortality associated with economically significant systemic bacterial diseases of fish. Florfenicol (FFC) is effective in controlling mortality associated with Streptococcus iniae in tilapia Oreochromis sp. when administered in medicated feed at a dose of 15 mg/kg bodyweight (BW)/d for 10 consecutive days. Our objective was to characterize the depletion of the FFC marker residue, florfenicol amine (FFA), from the edible tissue of market-weight Nile tilapia O. niloticus x O. niloticus and hybrid tilapia O. niloticus x O. aureus offered feed medicated with FFC at a nominal dose rate of 15 mg/kg BW/d for 12 days. Near market-weight tilapia were obtained from a commercial tilapia farm, distributed to 2 single pass (one for Nile tilapia and one for hybrid tilapia), flow-through systems and maintained at 27 ??C under a 15 h light:9 h dark photoperiod over a 41-d pre-dosing period. During the dosing period, tilapia were offered feed medicated with FFC at a concentration of 1.479 g/kg at 1% BW daily divided in three equal offerings. The initial 10-d dosing period was extended to 12 d because one tank did not consume > 75% of the feed offered during the first two dosing days. The total dose consumed by fish in each of the 2 tanks ranged from 147 to 167 mg/kg. Once during the pre-dose period and on days 1, 2, 4, 7, 14, 21, and 28 of the post-dose period, groups of fish were indiscriminately removed from each tank, measured for weight and length, scaled, filleted, and the skin-on fillets stored at tilapia fillet after withdrawal from medication and depletion followed first-order kinetics with an estimated half-life of 2.32 d. The FFA tolerance limit, calculated as the 99th percentile of the potential residue level at 95% confidence, had depleted to less than the 1 ??g/g maximum residue level by 6.14 d after the dosing period.

Depletion of florfenicol amine, marker residue of florfenicol, from the edible fillet of tilapia (Oreochromis niloticus x O. niloticus and O. niloticus x O. aureus) following florfenicol administration in feed

Science.gov (United States)

Gaikowski, M.P.; Mushtaq, M.; Cassidy, P.; Meinertz, J.R.; Schleis, S.M.; Sweeney, D.; Endris, R.G.

2010-01-01

Aquaflor??, a 50% feed premix containing the broad spectrum antibacterial agent florfenicol is available globally to control mortality associated with economically significant systemic bacterial diseases of fish. Florfenicol (FFC) is effective in controlling mortality associated with Streptococcus iniae in tilapia Oreochromis sp. when administered in medicated feed at a dose of 15 mg/kg bodyweight (BW)/d for 10 consecutive days. Our objective was to characterize the depletion of the FFC marker residue, florfenicol amine (FFA), from the edible tissue of market-weight Nile tilapia O. niloticus x O. niloticus and hybrid tilapia O. niloticus x O. aureus offered feed medicated with FFC at a nominal dose rate of 15 mg/kg BW/d for 12 days. Near market-weight tilapia were obtained from a commercial tilapia farm, distributed to 2 single pass (one for Nile tilapia and one for hybrid tilapia), flow-through systems and maintained at 27 ??C under a 15 h light:9 h dark photoperiod over a 41-d pre-dosing period. During the dosing period, tilapia were offered feed medicated with FFC at a concentration of 1.479 g/kg at 1% BW daily divided in three equal offerings. The initial 10-d dosing period was extended to 12 d because one tank did not consume > 75% of the feed offered during the first two dosing days. The total dose consumed by fish in each of the 2 tanks ranged from 147 to 167 mg/kg. Once during the pre-dose period and on days 1, 2, 4, 7, 14, 21, and 28 of the post-dose period, groups of fish were indiscriminately removed from each tank, measured for weight and length, scaled, filleted, and the skin-on fillets stored at UV detection. Florfenicol amine is rapidly eliminated from tilapia fillet after withdrawal from medication and depletion followed first-order kinetics with an estimated half-life of 2.32 d. The FFA tolerance limit, calculated as the 99th percentile of the potential residue level at 95% confidence, had depleted to less than the 1 ??g/g maximum residue level by

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

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...... experiment, fish were injected with bacterial endotoxin lipopolysaccharide (LPS) either at ZT3 (day) or at ZT15 (night) to evaluate the temporal sensitivity of humoral immunity to a pathogen-associated molecular pattern. The results demonstrated that responses to LPS were gated by the time of day. LPS...... significantly modulated serum ALP and ANTI activities but only when the endotoxin was administered at ZT3. Serum LYZ and PER were stimulated at both injection times but with differing response profiles. Modulated LYZ activity was persistent when injected at ZT3 but transient when LPS was applied at ZT15...

Antibiotic resistence of Aeromonas hydrophila isolated from Piaractus mesopotamicus (Holmberg, 1887 and Oreochromis niloticus (Linnaeus, 1758 Resistência de Aeromonas hydrophila isolada de Piaractus mesopotamicus (Holmberg, 1887 e Oreochromis niloticus (Linnaeus, 1758 a antibióticos

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Andréa Belém-Costa

2006-06-01

Full Text Available One of the most important problems involving treatments with antibiotics against Aeromonas hydrophila isolated from fishes is that antibiotic resistance develops readily. The antimicrobial activity of chemotherapeutants in isolates from pacu Piaractus mesopotamicus (Holmberg, 1887 and tilapia Oreochromis niloticus (Linnaeus, 1758 was tested by the Kirby-Bauer disk method, over Mueller-Hinton surface agar previously inoculated with 100 µL of bacterial suspensions. After regular incubation, isolates from tilapia and pacu were uniformly resistant to amoxicillin, ampicillin, lincomycin, novobiocin, oxacillin, penicillin, and trimetoprim+sulfametoxazole. The A. hydrophila type strain presented resistance to the same antimicrobial substances and also against rifampicin; the bacterial isolate from pacu were the only strain resistant to tetracyclin. Isolates from both pacu and tilapia had intermediate reaction with erytromycin. The use of drugs in commercial fish farms in Brazil can favor the development of resistant bacterial strains in native fish species as already observed for exotic species, commercially produced for longer time.Um dos maiores problemas envolvendo o tratamento com antibióticos contra Aeromonas hydrophila isolada de peixes confinados é a rápida resistência ao antibiótico desenvolvida pela bactéria. A atividade antimicrobiana de quimioterapêuticos em isolados a partir de pacu Piaractus mesopotamicus (Holmberg, 1887 e tilápia Oreochromis niloticus (Linnaeus, 1758 foi verificada pelo método de difusão de antibiótico em discos de Kirby-Bauer, sobre uma superfície de Agar Mueller-Hinton previamente inoculada com 100 µL de suspensão bacteriana. Após o período de incubação, os isolados de tilápia e pacu foram uniformemente resistentes a amoxicilina, ampicilina, lincomicina, novobiocina, oxacilina, penicilina e trimetoprim+sulfametoxazol. A cepa tipo para A. hydrophila apresentou resistência às mesmas subst

Water Quality Improvement of Media Culture for Tilapia (Oreochromis niloticus) with Cleaner Production Method

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Haeruddin; Supriharyono; Febrianto, S.

2018-02-01

The tilapia (Oreochromis niloticus), is known as a high adaptability and brackish water tolerance fish. This fish is also has a meat with high protein content, that ranges about 65 -75%. Generally the tilapia is cultured using a conventional system with high density. It is caused degradation of water quality of media culture, and finally increase mortality rate of fish cultured. The application of tilapia cultivation with cleaner production method by giving enzyme into the feed to upgrade the efficiency of feed utilization, presumed that could improve the water quality of cultivation media. It is due to the lower of feed and feces residues. Therefore the concentration of toxic compounds, such as ammonia, nitrite and sulfide, will be lower. The experiments were conducted for 35 days with a completely factorial randomized design. The first factor was the dosage of enzyme in the feed, consisting of 4 dosages, and the second factor was the duration of the test fish maintenance (5 weeks). Water quality variables examined included ammonia, nitrite and sulfide. The results showed that enzyme dosage had no significantly impact on ammonia, nitrite and sulfide concentrations in the test media culture. However, the feeding with enzyme in low dosage, resulted less concentration of ammonia, nitrite and sulfide than it was without enzyme). The duration of fish cultured has significantly effect on the concentration of ammonia, nitrite and sulfide in the test media. While it is no significantly correlation between dosage and duration of maintenance.

Bioactivity of crude ethanol extract and fractions of Eugenia uniflora (Myrtaceae in the hepatopancreas of Oreochromis niloticus L

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TATIANA S FIUZA

2009-01-01

Full Text Available This study evaluates the bioactivity of the crude ethanol extract and ethyl acetate, hexane and chloroform fractions obtained from Eugenia uniflora leaves using the hepatopancreas of Oreochromis niloticus L. as an experimental model. The ethanol extract and fractions were administered to the fish orally with their feed. Twenty-four hours later, the fish were sacrificed and their livers dissected, fixed in neutral formalin, embedded in paraffin and sectioned. Histological analyses were performed using Masson's trichrome and Haematoxylin-Eosin. Histochemical studies were performed using Feulgen, PAS (Periodic Acid Schiff and PAS + salivary amylase and Sudan IV stain. The qualitative analysis of the material showed that the crude extract and the ethyl, chloroform and hexane fractions induced vasodilation, vascular congestion and toxicity due to the presence of eosinophilic granular cells, rodlet cells, some leukocytic infiltrate and rare focal necroses. The Nile tilapia proved to be a satisfactory model for screening plant products.

Effect of dietary fish meal replacement by red algae, Gracilaria arcuata, on growth performance and body composition of Nile tilapia Oreochromis niloticus.

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Younis, El-Sayed M; Al-Quffail, Abdullah S; Al-Asgah, Nasser A; Abdel-Warith, Abdel-Wahab A; Al-Hafedh, Yousef S

2018-02-01

A 12-week long feeding experiment was initiated to evaluate the effect of dietary supplementation of red algae, Gracilaria arcuata , on the growth performance, feed utilization and body composition of Nile tilapia Oreochromis niloticus (Linnaeus, 1758). The fish were fed with an algae-free control diet (C) and three experimental diets which replaced conventional fish meal with varying levels of dried G. arcuata (20%, 40% and 60%, represented as G20, G40 and G60, respectively). The growth parameters of final weight (FW), weight gain (WG), percentage of weight gain (WG%), daily growth rate (DGR) and specific growth rate (SGR) were significantly reduced (P algae incorporation compared to the control diet. Moreover, the negative impact of Gracilaria meal on the growth performance of Nile tilapia increased as the proportion of algae in the diet increased, with fish on diet G20 exhibiting a significantly higher growth performance than the fish on either of the G40 and G60 diets. On the other hand, the feed utilization parameters feed conversion ratio (FCR) and protein efficiency ratio (PER) did not show significant differences between the fish in the control group and those on diet G20, although poorer FCR and PER outcomes were achieved in the case of fish on diet G60. The content of moisture, protein and ash in muscle and carcass increased as the proportion of Gracilaria meal in the diets increased, but the reverse was true for lipid level. These results indicate that incorporation of less than 20% red algae, Gracilaria arcuata , could be feasible in the diet of Nile tilapia and further studies are recommended to optimize the level of algae to improve growth performance.

EFECTO DE TILAPIA Oreochromis niloticus SOBRE LA PRODUCCIÓN PESQUERA DEL EMBALSE EL GUÁJARO ATLÁNTICO - COLOMBIA

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Pedro Caraballo G, M.Sc.

2009-12-01

Full Text Available Objetivo. Evaluar el efecto de tilapia Oreochromis niloticus sobre la producción pesquera en el embalse de El Guájaro, departamento del Atlántico, Colombia. Materiales y métodos. El embalse tiene un área aproximada de 14.000 ha y allí pescan diariamente 2.500 pescadores provenientes de ocho municipios que rodean el ecosistema. Por medio de evaluaciones mensuales del desembarco durante 48 horas en todos los puertos, fue evaluada la composición y abundancia de las capturas en 1988 y 2002. Los resultados de la evaluación hecha en 2002 fueron comparados con los obtenidos en 1988. Resultados. 38 especies de peces, perteneciendo a 14 familias fueron identificadas. Sólo las dos especies que dominan las capturas, presentaron una variación en su participación global. La producción durante 2002 fue de 431 ton/mes, superior a las 84 ton/mes evaluadas en el año 1988. Durante 2002, las capturas fueron dominadas por tilapia Oreochromis niloticus (53% y arenca Triportheus magdalenae (36% lo que representa una variación en la composición de las capturas que, durante 1988 fueron respectivamente de 13% y 73%. Esta variación no afectó la proporción de herbívoros y carnívoros que se mantuvo en 90-10%. Conclusiones. La variación en la composición y abundancia de la producción total implica el desplazamiento de una especie nativa (Triportheus magdalenae por una exótica (Oreochromis niloticus, hecho que viene siendo observado en toda la cuenca del Magdalena en esta década.

Relação parasito-hospedeiro em peixes de pisciculturas da região de Assis, Estado de São Paulo, Brasil. 1. Oreochromis niloticus (Linnaeus, 1757 - DOI: 10.4025/actascibiolsci.v29i2.594 Host-parasite relationship in fish from fish farms in the Assis region, São Paulo State, Brazil. 1. Oreochromis niloticus (Linnaeus, 1757

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Maria José Tavares Ranzani-Paiva

2007-12-01

Full Text Available Um total de 90 espécimes de Oreochromis niloticus foi coletado bimestralmente entre os meses de fevereiro a dezembro de 2004, em três pisciculturas do Estado de São Paulo. Do total, 82,2% estavam parasitados por pelo menos uma espécie de parasito. Os parâmetros físicos e químicos da água foram utilizados para caracterizar a qualidade da água em cada propriedade. Sete espécies de ectoparasitos foram registradas. Foi possível observar que as pisciculturas apresentam a mesma parasitofauna, porém cada propriedade apresenta uma estrutura da comunidade peculiar. Cichlidogyrus sclerosus e Cichlidogyrus sp. 1 apresentaram correlação negativa significativa da abundância com o comprimento padrão do hospedeiro somente em Palmital. A espécie Cichlidogyrus sp. 2 e o copépode Lamproglena sp. apresentaram correlação positiva significativa da abundância com o comprimento padrão nas pisciculturas de Tarumã e Cândido Mota, respectivamente. Em relação ao fator de condição relativo, somente a espécie Cichlidogyrus sp. 1 apresentou correlação significativa negativa com a abundância de parasitismo. Lamproglena sp. apresentou correlação positiva significativa com a relação hepatossomática (RHS das tilápias em Palmital, e o ergasilídeo apresentou correlação significativa negativa da abundância de parasitismo e a relação esplenossomática (RES dos hospedeiros em Cândido Mota.A total of ninety specimens of Oreochromis niloticus were collected every other month between February and December of 2004 at three fish farms in São Paulo State. 82.2% were parasitized by at least one species of parasite. Physical and chemical water parameters were used to characterize water quality in each fish farm. Seven species of ectoparasites were registered. It was possible to observe that all fish farms presented the same parasite fauna; however, each farm featured its own peculiar community structure. Cichlidogyrus sclerosus and Cichlidogyrus

Assessment of biological effects of pollutants in a hyper eutrophic tropical water body, Lake Beira, Sri Lanka using multiple biomarker responses of resident fish, Nile tilapia (Oreochromis niloticus).

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Pathiratne, Asoka; Pathiratne, K A S; De Seram, P K C

2010-08-01

Biomarkers measured at the molecular and cellular level in fish have been proposed as sensitive "early warning" tools for biological effect measurements in environmental quality assessments. Lake Beira is a hypertrophic urban water body with a complex mixture of pollutants including polycyclic aromatic hydrocarbons (PAHs) and Microcystins. In this study, a suite of biomarker responses viz. biliary fluorescent aromatic compounds (FACs), hepatic ethoxyresorufin O-deethylase (EROD) and glutathione S-transferase (GST), brain and muscle cholinesterases (ChE), serum sorbitol dehydrogenase (SDH), and liver histology of Oreochromis niloticus, the dominant fish inhabiting this tropical Lake were evaluated to assess the pollution exposure and biological effects. Some fish sampled in the dry periods demonstrated prominent structural abnormalities in the liver and concomitant increase in serum SDH and reduction in hepatic GST activities in comparison to the control fish and the fish sampled in the rainy periods. The resident fish with apparently normal liver demonstrated induction of hepatic EROD and GST activities and increase in biliary FACs irrespective of the sampling period indicating bioavailability of PAHs. Muscle ChE activities of the resident fish were depressed significantly indicating exposure to anticholinesterase substances. The results revealed that fish populations residing in this Lake is under threat due to the pollution stress. Hepatic abnormalities in the fish may be mainly associated with the pollution stress due to recurrent exposure to PAHs and toxigenic Microcystis blooms in the Lake.

Digestibility and nutrient utilisation of soybean bran-based diets in Nile tilapia Oreochromis niloticus

OpenAIRE

Sadiku, S.O.E.; Alao, I.A.; Tiamiyu, L.O.

2003-01-01

The digestibility and utilisation of two soybean bran-based diets and two fishmeal-based diets serving as control, at optimal (30%) and suboptimal (20%) protein levels were evaluated in Oreochromis niloticus. These were Diet I (Control)-fishmeal based diet at 30% crude protein, Diet II (Control) - fishmeal based diet at 20% crude protein, Diet III - hydrolysed Soybean Bran based diet at 30% crude protein, Diet IV - hydrolysed Soybean Bran based diet at 20%. Dry matter digestibility differed i...

Oxidative stress responses in gills of tilapia (Oreochromis niloticus) at different salinities

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Handayani, Kiki Syaputri; Novianty, Zahra; Saputri, Miftahul Rohmah; Irawan, Bambang; Soegianto, Agoes

2017-08-01

The objective of present study is to evaluate the impact of different salinities on the levels of CAT, GSH and MDA of the gills of Nile tilapia (Oreochromis niloticus). Nile tilapia was treated by exposure to salinities concentration 0 ‰, 5 ‰ and 10 ‰. Research models were weakened and sacrificed, then took the left and right sides of the gills. The result of gills homogenity was centrifuged for supernatan, then supernatan was proceed with testing levels of CAT, GSH and MDA by ELISA assay methods. The levels of CAT in gills were significantly higher at 10 ‰ than at 5 ‰ and 0 ‰. The levels of GSH in gills were significantly higher at 0 ‰ than 5 ‰. The levels of GSH in gills at 5 ‰ and 10 ‰ salinities were not significantly different. The levels of MDA in gills at salinity 10 ‰ and 5 ‰ were higher than in control gills at 0 ‰ salinities. This occurs because the salinity of 10 ‰ salinity was optimal for live of fish tilapia. In conclusion, salinity impact the increasing of CAT, GSH, and MDA levels in gills of Nile tilapia.

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

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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.

Effect of Cooking Method on the Proximate, Amino Acid and Fatty Acid Compositions of Clarias gariepinus and Oreochromis niloticus

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Omolara Olusola Oluwaniyi

2016-10-01

Full Text Available The proximate, amino acid and fatty acid compositions of the fillet and oil from Clarias gariepinus (Catfish and Oreochromis niloticus (Tilapia were determined. The moisture content ranged from 76.27 % for catfish to 79.97 % for tilapia while the oil content ranged from 7.80 % for tilapia and 11.00 % for catfish. Ash content was in the range 8.03 – 9.16 % and the protein content was 15.83 - 18.48 %. Cooking – boiling, roasting or frying – resulted in a variation in the nutrient composition but with no significant effect on the amino acid composition except for the samples fried with palm oil which resulted in significantly reduced essential amino acids contents. All the fish samples – both fresh and processed – have amino acid scores less than 100, with lysine, threonine and the sulphur-containing amino acids being among the limiting amino acids. Both fish samples contain more unsaturated than saturated fatty acids.

Complete genome sequence of Edwardsiella ictaluri isolate RUSVM-1 recovered from nile tilapia (Oreochromis niloticus) in the Western Hemisphere

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Edwardsiella ictaluri is a Gram-negative, bacillus that has recently been implicated in disease outbreaks in tilapia and zebrafish. We report here the complete and annotated genome of an isolate from a Nile Tilapia (Oreochromis niloticus), which contains a chromosome of 3,630,639 bp and two plasmids...

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.

Light and ultrastructural studies on liver of Oreochromis niloticus fry grown in tritiated water during embryonic development

Energy Technology Data Exchange (ETDEWEB)

Carino, V S; Alvendia-Casauay, A [Institute of Biology, College of Science, University of the Philippines, Diliman, Quezon City (Philippines)

1991-01-01

Oreochromis niloticus embryos of different developmental stages were reared in tritiated water at 3.7, 0.37, 0.037, and 0 GBq/1 and harvested at day 21 stage. In general, gross morphology of liver was altered in fry reared in higher tritium concentrations and in fry reared in tritiated water at earlier stages of development. Under light microscopy, fatty infiltration of liver parenchyma, presence of unresorped yolk sac, occasional vacuolation in cytoplasm of hepatocytes, widening of sinusoids, and increased size of space of Disse were observed in liver of fry reared in tritiated water at higher concentrations. At the electron microscope level, swollen mitochondria, fragmented rough endoplasmic reticulum, and insconspicuous glycogen granules compared to control were noted in liver of treated fish. This study give basic information on how cells may be affected by irradiation at the histological, cellular, and subcellular level. (auth.). 8 figs.; 1 tab.

Effects of irradiation and refrigeration on the nutrients and shelf-life of tilapia (Oreochromis niloticus);Efeitos da irradiacao e refrigeracao na qualidade e no valor nutritivo da tilapia (Oreochromis niloticus)

Energy Technology Data Exchange (ETDEWEB)

Siqueira, Alessandra Aparecida Zilio Cozzo de

2001-07-01

The objective of this study is to enhance the shelf-life of processed fish, combining ionizing radiation and refrigeration with minimal processing. The physical, chemical, nutritional and microbiological characteristics of the specie Tilapia nilotica (Oreochromis niloticus) were studied in eviscerated samples and in commercial cuts. The fish were separated into samples irradiated with 1.0, 2.2 and 5 kGy and non-irradiated samples. They were stored at temperatures ranging from 0.5 deg C to -2 deg C for 20 and 30 days. During storage, the level of moisture in the non-irradiated samples decreased and the levels of protein and lipid increased while the irradiated samples remained stable. The levels of pH, TVB-N and NPN increased in the non-irradiated samples but tended to remain stable in the irradiated fish samples. During storage, microbiological analyses for the presence of coliforms proved the efficiency of the irradiation process. The irradiated samples had a microbiological content below the levels established by the Brazilian seafood legislation, whereas the non-irradiated samples had a higher microbiological content and were not in conformity with the officially permitted levels. Salmonella spp. and Staphylococcus aureus were not detected. The levels of amino acids in muscles and fatty acids in oil remained stable in the irradiated fish stored samples but decreased in the non-irradiated ones. Lipid-oxidation, measured by the TBARS test, showed a tendency to increase when the dose of irradiation increased. The storage products after 30 days showed good acceptability for sensorial parameters, appearance, odour, color and texture, so it is possible to increase the shelf life of a minimally processed tilapia using combined irradiation and refrigeration. (author)

Formation of ring marks in stocked tilapia juveniles (Oreochromis aureus/O. niloticus (Perciformes: Cichlidae

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Ana L Ibañez

2007-12-01

Full Text Available Lake Metztitlán was dried up completely in the spring of 1998 and refilled in August of that year. In the period September-November, two cohorts of 1.6 million juveniles of a tilapia hybrid were stocked (Oreochromis aureus/O. niloticus, and monitored every month for one year. Since the date of birth of these juveniles was known, the analyses focused on whether the ring marks of the scales, sagittae and opercula or the circuli of the scales could be used to age them. The ring marks of the scales and opercula showed great variability, and the sagittae had a significant relationship with length, but it is unclear if at least the first ring mark could be formed at the hatchery and reflect changes in diet and/or tank movements in the fish farm. The circuli had a continuous regular behavior, with a formation rate of 10.38±0.93 and 11.38±0.95 circuli/month for the first and second cohorts, respectively. This proportion was maintained during the study period, and could be of help to calculate an approximate age of juveniles, especially in stocked fish that show multiple ring marks because of manipulation in fish farms and stocking events. Rev. Biol. Trop. 55 (3-4: 1005-1013. Epub 2007 December, 28.El lago de Metztitlán se secó completamente en la primavera de 1998, inundándose nuevamente en agosto del mismo año para ser repoblado entre septiembre y noviembre con 1.6 millones de jóvenes de un híbrido de tilapia (Oreochromis aureus/O. niloticus en dos periodos. Ambas cohortes fueron monitoreadas mensualmente durante un año. Debido a que la fecha de nacimiento era conocida, el objetivo del estudio fue evaluar si las marcas anulares de las escamas, las sagittae y los opérculos, o los circuli de las escamas pueden usarse para estimar la edad. Los anillos de las escamas y opérculos mostraron gran variabilidad, mientras que las de las sagittae se relacionaron significativamente con la longitud, sin embargo no quedó claro si al menos el primer

Enterococcus, Myroides, and Exiguobacterium: Bacterial Genus with Probiotic Potential for Nile Tilapia (Oreochromis niloticus Culture

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Luisa Marcela Villamil Díaz

2017-09-01

Full Text Available 120 bacteria were isolated from tilapia intestine and screened according to the antibacterial activity against pathogens such as Aeromonas hydrophila, Edwardsiella tarda and Streptococcus agalactiae, the ability to adhere to intestinal mucus and growth kinetics. The selected bacteria were identified by 16S rRNA sequencing of and were identified as Exigobacterium sp. I9, Enterococcus faecalis I15 and Myroides odoratimimus I19. Furthermore, the in vivo effect on fish growth was assessed by the addition of selected bacteria to juvenile Oreochromis niloticus feed (106 CFU / g, for 15 days. Survival was also determined after a challenge by intraperitoneal injection of E. tarda (100 μL of 105 UFC / mL. The three selected bacteria increased the specific growth rate, reduced mortality of fish during the experimental challenge with E. tarda and did not cause mortality during the addition in the feed. The positive effects observed in vivo are possibly associated with in vitro activity; however, for biosafety reasons, it is recommended that further studies of Exigobacterium sp. I9 and E. faecalis I15 may be carried out since this genus have been reported of as causative agents of fish mortality, whereas in the case of M. odoratimimus I19, verification of positive effects at a higher production scales is desirable.

Effects of dietary supplementation with green tea waste on growth, digestive enzyme and lipid metabolism of juvenile hybrid tilapia, Oreochromis niloticus × O. aureus.

Science.gov (United States)

Zheng, Qingmei; Han, Chunyan; Zhong, Yanmei; Wen, Rushu; Zhong, Ming

2017-04-01

An 8-week feeding trial was conducted to evaluate the effects of dietary supplementation with green tea waste (GTW) on growth, digestive enzyme and lipid metabolism of juvenile hybrid tilapia, Oreochromis niloticus × O. aureus. The fish (initial mean body weight, 12.63 ± 0.75 g) were fed five experimental diets that included 0 (control), 0.8, 1.6, 3.2 or 6.4 % of GTW in triplicate aquaria, twice daily. Growth performance, plasma metabolites content and liver and intestine digestive enzyme activities were determined. Fish accepted well all experimental diets during the trial, and no mortality was observed. The weight gain increased (P tilapia to improve growth performance, digestion efficacy and fat metabolism.

Effects of replacing fishmeal with wastes derived from local fisheries on the growth of juvenile tilapia, Oreochromis niloticus

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Chanagun Chitmanat

2009-01-01

Full Text Available A feeding trial was conducted to investigate the effects of partially and totally replacing fishmeal with by-product derived from local fisheries on growth performances of tilapia (Oreochromis niloticus. Tilapia fingerlings (average initialweight 0.38±0.05 g were fed with 5 different diet formulas composing of fish meal protein replacement levels of 0%, 25%,50%, 75, and 100%. Tilapia were raised in 80 x 80 x 80 cm3 hapa in an earthen pond for 8 weeks. Each treatment contained3 replications. No feeding trial was applied as negative control. The result showed that fish by-product powder could substitute for fishmeal on a crude protein basis at a level of not more than 25%. As a result, feed cost can only be cut down approximately 3 US cents/kg. Specific growth rate, weight gain, survival rate and feed conversion ratio were not significantly different between the fish fed with the 75% and 100% fishmeal containing diets (P>0.05. The outcome would beapplied to reduce the solid wastes from fish processing and partially replace the imported fishmeal. This can also be used as guideline for farmers in small communities to produce their own tilapia feed.

Effects of substrate addition and supplemental feeding on plankton composition and production in tilapia (Oreochromis niloticus) and freshwater prawn (Macrobrachium rosenbergii) polyculture

NARCIS (Netherlands)

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

2009-01-01

This study investigated the effects of substrates and supplemental feeding on growth and production of tilapia (Oreochromis niloticus) and freshwater prawn (Macrobrachium rosenbergii) in a polyculture system. On actual farms, four treatments were evaluated in triplicate: substrate plus feed (herein

Characteristic study of chitosan addition in Tilapia (Oreochromis niloticus) bone based gelatin film

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Atmaka, W.; Yudhistira, B.; Putro, M. I. S.

2018-03-01

Tilapia (Oreochromis niloticus) is one of popular fish species in Indonesia. The high number in tilapia’s production and export of tilapia resulting in the increase of bone fish waste. an attempt to decrease the amount of the aforementioned waste, the fish bones were turned into gelatine. The gelatine produced from this waste can be put to good use by turning it into edible film due to its high water resistance and low tensile strength value. However, in order to make a proper film, both the water resistance and the tensile strength value needs another appropriate additional biopolymer. In this case, the appropriate biopolymer needed both to form the film and to repair its characteristics is chitosan. The purpose of this research is to find out the effect of the chitosan addition on the tilapia bone based gelatine film. The research used several mixtures of gelatine (G) and chitosan (C) with the following ratio: G100:C0 (GC1), G75:C25 (GC2), G50:C50 (GC3), G25:C75 (GC4), G0:C100 (GC5). ANOVA results (Psolubility, tensile strength, elongation at break, Fourier Transform Infrared (FTIR), color a, and color b but no significant effects on the vapor permeability and color L. The best result is shown on GC2 with thickness 0.119 mm; solubility 74.95%; tensile strength 2.635 Mpa; elongation at break 68.26%; water vapor permeability 5.897 g/h m2 and FTIR. The parameters in GC2 shows good compatibility between the two biopolymers.

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

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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

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

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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.

Recycling of sewage sludge: Feeding Nile tilapia, Oreochromis niloticus (Linn.), with irradiated and dried sludge from beer industry

International Nuclear Information System (INIS)

Chuapoehuk, W.; Piadang, S.; Tinnungwattana, W.

1998-01-01

Recycling of sewage sludge from wastewater treatment plant of beer industry as supplemental feed for fish was conducted. Industrial biosludge from wastewater treatment plant of beer industry was irradiated at 3.32 kGy gamma irradiator, carrier type, model JS 8900, 60 Co activity at 187,088.121 Ci on 6 June 1995. For fish production study, it is needed to change the wet sludge to dry powder form by Rotadics dryer, type Stord TST 3.4 C, Stord (Thailand) Co. Ltd., at the maximum capacity of 15 T/24 h. The moisture content of finished product is at 8-10%. Fish control diet was then replaced at 60% by weight with irradiated and dried sludge to become as test diet. Nile tilapia, Oreochromis niloticus (Linn.), fingerlings averaging 0.67 g. in body weight was stocked into earthern ponds of 400 square meters at the density of 5 fishes per square metre. Fish were fed with two diets, control diet and test diet, for 154 days. There are no statistical differences in specific growth rate, quality of the fish flesh (Cd and Pb concentration, edible portion and off flavour) and pond water quality. Survival rate and feed conversion efficiency of the fish fed test diet are higher than control diet (P<0.05). Replacement of irradiated sludge can decrease the cost of fish production and results in better benefit than that of control diet

Use of Cassia alata aqueous extract as a bath treatment to control Pseudomonas anguilliseptica infection in tilapia (Oreochromis niloticus

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Phumkhachorn Parichat

2015-01-01

Full Text Available The aqueous extracts of six plants, Andrographis paniculata, Cassia alata, Centella asiatica, Garcinia mangostana, Punica granatum and Psidium guajava, were investigated for their antimicrobial activity and mode of action against Pseudomonas anguilliseptica, an important fish pathogenic bacterium, which is responsible for economic losses in aquaculture worldwide. Among the tested plant extracts, the C. alata aqueous extract had the strongest inhibitory effect and exhibited a bactericidal mode of action against the pathogenic bacterium. When an infection of tilapia (Oreochromis niloticus with P. anguilliseptica was induced by intraperitoneal, the median lethal dose (LD50 was determined to be 1.59 x 105 CFU/ml. For the in vivo trial, four different concentrations (25, 50, 75 and 100 ppm of C. alata aqueous extract were used as bath treatment to remedy the infection. The effect of the extract on the infection was dose-dependent and an extract with the concentration of 100 ppm eliminated mortality of the infected fish without producing any adverse effects on the animals. This study suggests that C. alata aqueous extract has the potential to control fish disease caused by P. anguilliseptica.

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...

Effect of fermented, hardened, and dehulled of chickpea (Cicer arietinum) meals in digestibility and antinutrients in diets for tilapia (Oreochromis niloticus)

International Nuclear Information System (INIS)

Valdez-González, F.J.; Gutiérrez-Dorado, R.; García-Ulloa, M.; Cuevas-Rodríguez, B.; Rodríguez-González, H.

2018-01-01

Among the most typical feed sources for tilapia, plants represent a low-cost source in substituting for traditional high-cost feed ingredients. Fermentation, hardening and dehulling are common grains processing techniques to make plant nutrients available and more digestible to fish. Apparent digestibility coefficients (ADC) of dry matter and protein, and antinutrients (phytic acid and tannins) in fermented, hardened and dehulled chickpea (Cicer arietinum) meals were determined for juvenile Nile tilapia (Oreochromis niloticus). The highest ADC was obtained with processed (fermented, hardened and dehulled) chickpea meals compared with non-processed. Results indicated that fermentation increased the protein content by 13.1%, decreased the content of ash and phytic acid (47.5 and 45%, respectively), and increased the ingredient apparent digestibility of dry matter (ADM) by 23.2%, and the ingredient apparent digestibility of protein (ADP) by 41.9%. Dehulling meal increased the protein (5.7%) and lipid (6.4%) content of chickpea grains; decreased fiber, ash and tannin content (75.3%, 19.1%, and 84.5%, respectively); and increased ADM by 12.8%, and ADP by 10.4%. We conclude that fermented, hardened and dehulled chickpea meals represent a potential alternative in diets for juvenile O. niloticus.

Effect of polychlorinated biphenyls on osmoregulatory response and apoptosis in GIFT tilapia, Oreochromis niloticus.

Science.gov (United States)

Zheng, Y; Qiu, L; Fan, L; Song, C; Meng, S; Chen, J

2016-09-02

In the present study, GIFT tilapia Oreochromis niloticus were exposed to polychlorinated biphenyls (PCBs) for 7, 14, and 21 days. Over the duration of the exposure, genotoxicity and the activity of Na + /K + -ATPase (NKA) and Ca + /Mg + -ATPase (CMA) were measured in the gill, kidney, and intestine, to evaluate changes in osmoregulatory response in O. niloticus. Our results showed significant decreases in organic NKA (except in gill tissues after 0.5 mg/L PCB-exposure) and CMA activity. The results of the genotoxicity assay showed significant increases in atp1a1a, nkcc2 (only in gill tissue), and fxyd7 (except after 21 days of 5 mg/L PCB exposure). We found significant increases in caspase proteins in the liver in the 5-mg/L PCB exposure group, and the transcripts showed dose-dependent increases between treatment groups over the exposure duration. This study presents evidence that chronic exposure to PCB could result in organic osmoregulatory response and hepatic apoptosis in GIFT tilapia.

Effects of Clinoptilolite on Copper Accumulation of Oreochromis niloticus

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Nuray Çiftçi

2018-05-01

Full Text Available The copper accumulation in liver and gill tissues of Oreochromis niloticus, exposed to 2 ppm Cu and 1g/L clinoptilolite singly and to the same concentrations of their mixture over 24, 48, 72 and 96 hours was studied. ICP-AES spectrophotometer techniques were applied in determining tissue copper levels. Statistical evaluation of the experimental data was carried out by Student Newman Keul’s procedure. No mortality was observed during the experiments. Copper accumulation was lower in metal-clinoptilolite mixture group than metal singly group in gill tissue while no accumulation in both experimental groups in liver tissue (P<0.05. In addition, the copper level in the liver was lower in all experimental groups than in the control (P<0.05. Low Cu accumulation in gill tissue exposed in mixture groups can be explained by copper adsorption with chelating agent. The decrease of Cu reserves in the liver can be expressed by increase of copper-containing enzyme and protein synthesis.

Abundance, food habits, and breeding season of exotic T ilapia zillii and native O reochromis niloticus L. fish species in Lake Zwai , Ethiopia

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Padanillay C. Prabu

2008-05-01

Full Text Available Relative abundance, diet and breeding season overlap in the reproduction of exotic Tilapia zillii and native Oreochromis niloticus in Lake Zwai were studied from samples collected over 12 months. Younger fish of both species collected were also evaluated for food composition.Food items from stomachs of both species were collected and analysed using the frequency of occurrence method. In terms of number, T. zillii dominated O. niloticus at the sampling sites. In both species, macrophytes, detritus, blue green algae, diatoms, green algae, Ceratium, Euglena,and Phacus constituted foods of plant origin, whereas chironomid larvae, Copepoda, Cladocera,Rotifera, Nematoda, fish eggs, and fish scales constituted foods of animal origin. Foods of the latter type such as Ephemeroptera and mollusks were also noted in the diet of adult T. zillii.Despite the extensive overlap in food habits of the two species, however, the food items were found in the diet of the species with different average percentage frequencies of occurrence. The level of gonad maturation and gonadosomatic index (GSI values showed that in Lake Zwai breeding was year-round for both T. zillii and O. niloticus, with a peak during April-September and February-August respectively, indicating extended breeding season overlap in reproduction. The two species were always found together in the catches from the sampling sites, which indicated some niche overlap between them.

The effect of titanium dioxide nanoparticles on antioxidant gene expression in tilapia ( Oreochromis niloticus)

Science.gov (United States)

Varela-Valencia, Ruth; Gómez-Ortiz, Nikte; Oskam, Gerko; de Coss, Romeo; Rubio-Piña, Jorge; del Río-García, Marcela; Albores-Medina, Arnulfo; Zapata-Perez, Omar

2014-04-01

The reactivity of nanoparticles (NPs) in biological systems is well recognized, but there are huge gaps in our understanding of NP toxicity in fish, despite a number of recent ecotoxicity studies. Therefore, the aim of this research was to evaluate the effect of titanium dioxide NPs (TiO2-NPs) on antioxidant gene expression in the tilapia, Oreochromis niloticus. First, different sizes, shapes, and phases of TiO2-NPs were synthesized and characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), and dynamic light scattering (DLS). Fish were injected intraperitoneally with different concentrations (0.1, 1.0, 10.0 mg/L), sizes (7, 14, and 21 nm), and phases (anatase and rutile) of TiO2-NPs, and sacrificed 3, 6, 12, and 24 h after injection, when their livers were removed. Total RNA was extracted, and expression of the catalase ( CAT), glutathione- S-transferase ( GST), and superoxide dismutase ( SOD) genes was assessed by real-time polymerase chain reaction (RT-PCR). The results showed that injection of 1.0 mg/L TiO2-NPs induced an initial mild increase in CAT, GST, and SOD gene expression in tilapia, after which transcript levels decreased. Fish injected with 7 and 14 nm TiO2-NPs showed an increase in antioxidant transcript levels 6 h after treatment. Finally, the rutile form generated stronger induction of the GST gene than anatase TiO2-NPs during the first 6 h after injection, which suggests that exposure to rutile causes higher levels of reactive oxygen species to be produced.

Hepatic transcriptome analysis of juvenile GIFT tilapia (Oreochromis niloticus), fed diets supplemented with different concentrations of resveratrol.

Science.gov (United States)

Zheng, Yao; Wu, Wei; Hu, Gengdong; Zhao, Zhixiang; Meng, Shunlong; Fan, Limin; Song, Chao; Qiu, Liping; Chen, Jiazhang

2018-01-01

The GIFT (Genetically Improved Farmed Tilapia) tilapia, Oreochromis niloticus, is cultured widely for the production of freshwater fish in China. Streptococcosis, which is related to pathogenic infections, occurs frequently in juvenile and adult female GIFT individuals. Resveratrol (RES) has been used in feed to control these infections in freshwater tilapia. To address the effects of RES on tilapia, we used high-throughput RNA sequencing technology (RNA-Seq, HiSeq. 2500) to explore the global transcriptomic response and specific involvement of hepatic mRNA of juvenile O. niloticus fed with diets containing different concentrations of (0, 0.025, 0.05, and 0.1g/kg) RES. A total of > 24,513,018 clean reads were generated and then assembled into 23,244 unigenes. The unigenes were annotated by comparing them against non-redundant protein sequence (Nr), non-redundant nucleotide (Nt), Swiss-Prot, Pfam, Gene Ontology database (GO), Clusters of Orthologous Groups (COG) and Kyoto Encyclopedia of Genes and Genomes (KEGG) databases, and 12,578 unigenes were annotated to the GO database. A total of 1444 (0.025g/kg RES), 1526 (0.05g/kg RES), and 3135 (0.1g/kg RES) genes were detected as significant differentially expressed genes (DEGs), when compared with the controls. A total of 6 (0.025 vs 0.05g/kg RES), 19 (0.025 vs 0.1g/kg RES), and 124 (0.05 vs 0.1g/kg RES) genes were detected as significant DEGs. Six genes, including dnah7x1, sox4, fam46a, hsp90a, ddit4, and nmrk2, were associated with an immune response. These findings provide information on the innate immunity of GIFT and might contribute to the development of strategies for the effective management of diseases and long-term sustainability of O. niloticus culture. Copyright © 2017 Elsevier Inc. All rights reserved.

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

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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

Productive performance of Nile tilapia (Oreochromis niloticus fed at different frequencies and periods with automatic dispenser

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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.

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

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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.

Lamproglena monodi capart, 1944, attachment scheme and associatedpathology on the gills of oreochromis niloticus, with a special reference tothoracic appendages

International Nuclear Information System (INIS)

Ibrahim, Mohammed Has an

2008-01-01

This work comprises a parasitological and histopathological examinationof the Nile tilapia, Oreochromis niloticus, naturally infected withLamproglena monody (Crustacea: Lernaeidae). Fish specimens were collectedweekly from El-Minia Nile basin, Egypt Between April 2006 to March 2008).From a total of 420 fish examined, 96 (22.86%) were found infected.Attachment of L monodi was mainly enhanced by the armed maxillae that wereseen deeply introduced into the underlying tissues reaching the axialcartilage the gill filament. The maxillipeds were not involved in theattachment to the gill epithelium. Histological changes were restricted onlyto the free ends of gill filament, where copepods were found attached; thecentral and basal parts appeared normal and their gill lamellae remainedintact. Deep and shallow lesions associated sometimes with compressed orexfoliated hyperplastic epithelium were encountered in front of cephalothoraxand around oral apparatus of the parasite. In slight and moderate infectionsgill lamellae showed partial fusion. In many cases of heavy infection, theattacked area of gill filaments was eroded through. The cephalothorax wassometimes found in a deep cavity of the proliferated epithelium that wasinfiltrated by granular cells and lymphocytes. (author)

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.

Nickel exposure promotes osmoregulatory disturbances in Oreochromis niloticus gills: histopathological and energy dispersive spectrometry analysis.

Science.gov (United States)

Marcato, A C C; Yabuki, A T; Fontanetti, C S

2014-11-01

Water is an essential factor for maintaining the vital functions of living beings. Nickel is the 24th most abundant element on Earth; it is a heavy metal that is genotoxic and mutagenic in its chloride form. Due to industrial use, its concentration in surface sediments increased considerably. Fish develop characteristics that make them excellent experimental models for studying aquatic toxicology. They are particularly useful because they can alert of the potential danger of chemical substances or environmental pollution. Due to water quality impairment and because there are few published studies that relate nickel to tissue alteration, this study aimed to examine the consequences of nickel in an aquatic environment. For this analysis, individuals of Oreochromis niloticus were exposed for 96 h to three different concentrations of nickel dissolved in water according to the standard established by Brazilian law and compared them to a control group. After exposure, the gills were analyzed using X-ray microanalysis, ultramorphology, and histological and histochemical analysis. The results demonstrated that all the concentrations used in the experiment altered the histophysiology of the individuals exposed. In conclusion, the nickel presents a toxic potential to fish, even at the lowest concentration tested, which is equivalent to half of the concentration allowed by law. The CONAMA resolution should be revised for this parameter because of the interference of this metal in the histophysiology of the tested organism.

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...

The potential of mixed culture of genetically improved farmed tilapia (GIFT, Oreochromis niloticus) and freshwater giant prawn (Macrobrachium rosenbergii) in periphyton-based systems

NARCIS (Netherlands)

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

2006-01-01

The production performance of genetically improved farmed tilapia (GIFT, Oreochromis niloticus) and freshwater prawn (Macrobrachium rosenbergii) in periphyton-based systems were studied in farmers' ponds at Mymensingh, Bangladesh. Fifteen ponds (200-300 m2 area and 1.0-1.5 m in depth) were used to

Sex-Related Differences in Hematological Parameters and Organosomatic Indices of Oreochromis niloticus Exposed to Aflatoxin B1 Diet

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Esther Marijani

2017-01-01

Full Text Available A 24-week feeding experiment was conducted to assess whether males and females of Oreochromis niloticus exhibit differences in their hematological responses and organosomatic indices to dietary AFB1 contamination. Triplicate groups of O. niloticus (initial body weight: 24.1 ± 0.6 g were fed with four diets (Diets 1 to 4 containing 0, 20, 200, and 2,000 μg AFB1 kg−1. A significant decrease (P<0.05 in hemoglobin (Hb, red blood cells (RBC, and hematocrit (Hct was observed in AFB1 exposure groups, with the lowest levels recorded in the 2000 μg AFB1 kg−1 treatment. A significant increase in mean white blood cells (WBC, neutrophils, and lymphocytes was observed in AFB1 exposure groups. No sex-related differences in RBC, WBC, lymphocytes, monocytes, and neutrophils levels were observed. However, hemoglobin and hematocrit values for female O. niloticus were significantly lower than those for male O. niloticus. Organosomatic indices showed that the relative liver, kidney, and spleen weights were significantly higher (P<0.05 in the AFB1 supplemented group than in the control group. However, the effect of aflatoxin on organosomatic indices does not depend on sex but rather depends on the dose of aflatoxin in the diet. These results provide useful information for monitoring changes in the health status of male and female O. niloticus.

Mapping and validation of the major sex-determining region in Nile tilapia (Oreochromis niloticus L. Using RAD sequencing.

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Christos Palaiokostas

Full Text Available 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.

Effects of irradiation and refrigeration on the nutrients and shelf-life of tilapia (Oreochromis niloticus)

International Nuclear Information System (INIS)

Siqueira, Alessandra Aparecida Zilio Cozzo de

2001-01-01

The objective of this study is to enhance the shelf-life of processed fish, combining ionizing radiation and refrigeration with minimal processing. The physical, chemical, nutritional and microbiological characteristics of the specie Tilapia nilotica (Oreochromis niloticus) were studied in eviscerated samples and in commercial cuts. The fish were separated into samples irradiated with 1.0, 2.2 and 5 kGy and non-irradiated samples. They were stored at temperatures ranging from 0.5 deg C to -2 deg C for 20 and 30 days. During storage, the level of moisture in the non-irradiated samples decreased and the levels of protein and lipid increased while the irradiated samples remained stable. The levels of pH, TVB-N and NPN increased in the non-irradiated samples but tended to remain stable in the irradiated fish samples. During storage, microbiological analyses for the presence of coliforms proved the efficiency of the irradiation process. The irradiated samples had a microbiological content below the levels established by the Brazilian seafood legislation, whereas the non-irradiated samples had a higher microbiological content and were not in conformity with the officially permitted levels. Salmonella spp. and Staphylococcus aureus were not detected. The levels of amino acids in muscles and fatty acids in oil remained stable in the irradiated fish stored samples but decreased in the non-irradiated ones. Lipid-oxidation, measured by the TBARS test, showed a tendency to increase when the dose of irradiation increased. The storage products after 30 days showed good acceptability for sensorial parameters, appearance, odour, color and texture, so it is possible to increase the shelf life of a minimally processed tilapia using combined irradiation and refrigeration. (author)

Níveis de vitamina C e ferro para tilápia do nilo (Oreochromis niloticus Levels of vitamin C and iron for nile tilapia (Oreochromis niloticus

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Margarida Maria Barros

2002-11-01

Full Text Available Os efeitos de diferentes níveis de vitamina C e ferro no desempenho produtivo e parâmetros fisiológicos da tilápia do Nilo (Oreochromis niloticus foram avaliados por um período de 73 dias. O delineamento foi inteiramente casualizado, com tratamentos dispostos em esquema fatorial com três níveis de vitamina C (125; 375 e 1115 mg/kg e três níveis de ferro (30, 90 e 270 mg/kg, mais um tratamento adicional (0 mg/kg de suplementação de vitamina C e ferro, com quatro repetições cada tratamento, totalizando 10 grupos experimentais. Utilizaram-se 240 alevinos revertidos com peso médio inicial de 7,46 ± 0,49 g, distribuídos aleatoriamente em 40 aquários de 250 L, numa lotação de 6 peixes/aquário. Confeccionou-se dieta purificada com 32,0% de proteína bruta e 3300 kcal/kg de energia digestível. A ausência de vitamina C e ferro nas dietas propiciou o aparecimento de anemia microcítica e hipocrômica aos alevinos. A presença dessa vitamina em dosagens elevadas estimulou a liberação de eritrócitos imaturos na corrente sangüínea. Determinou-se, também, que níveis desses acima das exigências nutricionais descritas para a espécie não determinaram efeito detrimental no desempenho produtivo, na produção de proteínas plasmáticas ou nos aspectos morfológicos do fígado.The effects of different levels of vitamin C and iron on growth performance and physiological parameters on Nile tilapia (Oreochromis niloticus were evaluated for 73 days. A factorial experiment with three levels of vitamin C (125; 375 e 1115 mg/kg and three levels of iron (30, 90 e 270 mg/kg, plus an additional treatment (with 0 mg/kg of vitamin C and iron, was considered on a completely randomized design, with four replicates for each experimental group. It was randomly stocked 240 reverted fingerlings, an average weight of 7.46 ± 0.49 g, into 40, 250L, aquaria at a density of 6 fish/aquarium. A albumin-gelatin-diet was formulated to contain 32.0% of crude

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

Pemanfaatan Tepung Daun Lamtoro (Laucaena Gluca) Yang Telah Difermentasikan Dalam Pakan Buatan Terhadap Pertumbuhan Benih Ikan Nila Merah (Oreochromis Niloticus)

OpenAIRE

Restiningtyas, Rachma; Subandiyono, -; Pinandoyo, -

2015-01-01

Tepung daun lamtoro merupakan sumberdaya bahan baku yang potensial untuk bahan baku pakan ikan nila merah (Oreochromis niloticus). Namun pemanfaatannya terkendala dengan adanya kandungan zat antinutrisi yang terkandung di dalam daun lamtoro seperti neutral detergent fiber (NDF), acid detergent fiber (ADF), defisiensi asam amino esensial dan kandungan mimosin. Hasil fermentasi diharapkan terjadi peningkatan terhadap kualitas bahan pakan yang akan digunakan campuran pakan ikan. Daya cerna ika...

Laboratory-controlled Challenges of Nile Tilapia (Oreochromis niloticus) with Streptococcus agalactiae: Comparisons between Immersion, Oral, Intracoelomic and Intramuscular Routes of Infection.

Science.gov (United States)

Soto, E; Zayas, M; Tobar, J; Illanes, O; Yount, S; Francis, S; Dennis, M M

2016-11-01

Streptococcus agalactiae, the aetiological agent of streptococcosis in fish, is an important pathogen of cultured and wild fish worldwide. To gain a better understanding of the pathogenesis of streptococcosis in Nile tilapia (Oreochromis niloticus), and to identify the experimental route of infection that most closely mimics natural disease, fingerlings were challenged with S. agalactiae utilizing different delivery methods. Fingerlings were challenged via intracoelomic injection (ICinj), intramuscular injection (IMinj), orally or by immersion with serial dilutions of S. agalactiae. The dose lethal to 50% of test fish 15 days post challenge was 120 colony forming units (CFU)/fish after ICinj, and 10 5  CFU/fish after IMinj. Acute mortalities were present in both groups, but were higher in the fish challenged by ICinj. Very low mortalities were observed in the fish challenged via oral or immersion routes. Post-mortem evaluation of survivors revealed classical lesions associated with fish streptococcosis, including granulomatous or lymphohistiocytic epicarditis, splenitis, meningitis, myocarditis, choroiditis and exophthalmia. The information obtained improves our understanding of the pathogenesis of streptococcosis in fish, and provides useful information regarding controlled experimental infections in tilapia challenged with S. agalactiae. Results from this study suggest that IMinj challenge methods are not only suitable to induce streptococcosis in tilapia, but they may be the preferred method to study the pathogenesis of the naturally-occurring disease in this species. Copyright © 2016 Elsevier Ltd. All rights reserved.

Caracterização da mitocôndria isolada de fígado de tilápia-do-nilo (Oreochromis niloticus e alterações da bioenergética mitocondrial causadas pela exposição herbicida oxifluorfena Characterization of liver mitochondria from Nile tilapia (Oreochromis niloticus and mitochondrial bioenergetics alterations caused by exposure to oxyfluorfen herbicide

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F.P. Peixoto

2009-04-01

Full Text Available Descreve-se um método de isolamento de mitocôndrias acopladas de tilápia-do-nilo Oreochromis niloticus, isoladas de células hepáticas de peixes adultos. As mitocôndrias estavam metabolicamente ativas, sendo capazes de realizarem fosforilação oxidativa, de acordo com os valores do quociente de controle respiratório. Os valores de controle respiratório obtidos com malato/piruvato (complexo I e com succinato (complexo II foram de 5,8±0,8 e 3,38±0,4, respectivamente. O potencial de membrana exibiu o valor de 197±4mV, quer se utilizasse malato/piruvato ou succinato como substrato. O procedimento de isolamento de mitocôndrias de O. niloticus permite o estudo do efeito de xenobióticos na bioenergética mitocondrial, tendo sido avaliada a ação da oxifluorfena (0,6mgL-1 na bioenergética mitocondrial. Os resultados demonstram que o tratamento com oxifluorfena influencia a capacidade fosforilativa dos peixes, interferindo na sua carga energética, o que poderá levar à sua morte.A method for isolation of coupled mitochondria isolated from the liver of adult Nile tilapia Oreochromis niloticus is described for the first time. They were metabolically active, able to sustain oxidative phosphorylation, as shown by respiratory control ratio values, which were about 5.8±0.8 and 3.3±0.4 when respiring on malate/piruvate (complex I or succinate (complex II, respectively, as substrate. Membrane potential exhibited a value of approximately 197±4mV for malate/piruvate or succinate. The procedure now described for the isolation of O. niloticus mitochondria is an important new tool, allowing the study about the effect of xenobiotics on mitochondrial bioenergetic, being evaluated the effect of oxyfluorfen (0.6mgL-1 in the liver mitocondrial bioenergetic. These results showed that phosphorylation was significantly affected by oxyfluorfen which contributed to the decrease on the liver cell energy charge and consequently led to the fish dead.

Helminthiasis and gram negative enteric bacteria in freshwater fish from selected lakes of Haramaya District, Ethiopia

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Microbiological and helminthiasis examination of fish from Tinike and Adelle Lakes were conducted at Haramaya District, Ethiopia. The types of fish available in the lakes were also assessed. Adelle Lake has only Clarias gariepinus while the Tinike Lake has only Oreochromis niloticus fish species. Te...

An important natural genetic resource of Oreochromis niloticus (Linnaeus, 1758) threatened by aquaculture activities in Loboi drainage, Kenya.

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Ndiwa, Titus Chemandwa; Nyingi, Dorothy Wanja; Agnese, Jean-François

2014-01-01

The need to improve food security in Africa through culture of tilapias has led to transfer of different species from their natural ranges causing negative impacts on wild fish genetic resources. Loboi swamp in Kenya is fed by three hot springs: Lake Bogoria Hotel, Chelaba and Turtle Springs, hosting natural populations of Oreochromis niloticus. The present study aimed at better genetic characterization of these threatened populations. Partial mtDNA sequences of the D-loop region and variations at 16 microsatellite loci were assessed in the three hot spring populations and compared with three other natural populations of O. niloticus in the region. Results obtained indicated that the hot spring populations had mitochondrial and nuclear genetic variability similar to or higher than the large closely related populations. This may be attributed to the perennial nature of the hot springs, which do not depend on rainfall but rather receive permanent water supply from deep aquifers. The study also revealed that gene flow between the three different hot spring populations was sufficiently low thus allowing their differentiation. This differentiation was unexpected considering the very close proximity of the springs to each other. It is possible that the swamp creates a barrier to free movement of fish from one spring to the other thereby diminishing gene flow. Finally, the most surprising and worrying results were that the three hot spring populations are introgressed by mtDNA genes of O. leucostictus, while microsatellite analysis suggested that some nuclear genes may also have crossed the species barrier. It is very likely that the recent intensification of aquaculture activities in the Loboi drainage may be responsible for these introgressions. Taking into account the importance of these new genetic resources, protection and management actions of the Loboi swamp should be accorded top priority to prevent the loss of these spring populations.

An important natural genetic resource of Oreochromis niloticus (Linnaeus, 1758 threatened by aquaculture activities in Loboi drainage, Kenya.

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Titus Chemandwa Ndiwa

Full Text Available The need to improve food security in Africa through culture of tilapias has led to transfer of different species from their natural ranges causing negative impacts on wild fish genetic resources. Loboi swamp in Kenya is fed by three hot springs: Lake Bogoria Hotel, Chelaba and Turtle Springs, hosting natural populations of Oreochromis niloticus. The present study aimed at better genetic characterization of these threatened populations. Partial mtDNA sequences of the D-loop region and variations at 16 microsatellite loci were assessed in the three hot spring populations and compared with three other natural populations of O. niloticus in the region. Results obtained indicated that the hot spring populations had mitochondrial and nuclear genetic variability similar to or higher than the large closely related populations. This may be attributed to the perennial nature of the hot springs, which do not depend on rainfall but rather receive permanent water supply from deep aquifers. The study also revealed that gene flow between the three different hot spring populations was sufficiently low thus allowing their differentiation. This differentiation was unexpected considering the very close proximity of the springs to each other. It is possible that the swamp creates a barrier to free movement of fish from one spring to the other thereby diminishing gene flow. Finally, the most surprising and worrying results were that the three hot spring populations are introgressed by mtDNA genes of O. leucostictus, while microsatellite analysis suggested that some nuclear genes may also have crossed the species barrier. It is very likely that the recent intensification of aquaculture activities in the Loboi drainage may be responsible for these introgressions. Taking into account the importance of these new genetic resources, protection and management actions of the Loboi swamp should be accorded top priority to prevent the loss of these spring populations.

Brain Transcriptome Profiling Analysis of Nile Tilapia (Oreochromis niloticus Under Long-Term Hypersaline Stress

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Yan Liu

2018-03-01

Full Text Available The fish brain plays an important role in controlling growth, development, reproduction, and adaptation to environmental change. However, few studies stem from the perspective of whole transcriptome change in a fish brain and its response to long-term hypersaline stress. This study compares the differential transcriptomic responses of juvenile Nile tilapia (Oreochromis niloticus maintained for 8 weeks in brackish water (16 practical salinity units, psu and in freshwater. Fish brains from each treatment were collected for RNA-seq analysis to identify potential genes and pathways responding to hypersaline stress. A total of 27,089 genes were annotated, and 391 genes were expressed differently in the salinity treatment. Ten pathways containing 40 differentially expressed genes were identified in the tilapia brain. Antigen processing and presentation and phagosome were the two principally affected pathways in the immune system. Thirty-one of 40 genes were involved in various expressions associated with environmental information processing pathways such as neuroactive ligand-receptor interaction, cytokine-cytokine receptor interaction, the Jak-STAT signaling pathway, cell adhesion molecules (CAMs, and the PI3K-Akt signaling pathway, which are the upstream pathways for modulation of immunity and osmoregulation. The most-changed genes (>5-fold were all down-regulated, including four growth hormone/prolactin gene families, i.e., prolactin precursor (−10.62, prolactin-1 (−11, somatotropin (−10.15, somatolactin-like (−6.18, and two other genes [thyrotropin subunit beta (−7.73 and gonadotropin subunit beta-2 (−5.06] that stimulated prolactin release in tilapia. The downregulation pattern of these genes corroborates the decrease in tilapia immunity with increasing salinity and reveals an adaptive mechanism of tilapia to long-term hypersaline stress. Ovarian steroidogenesis, isoquinoline alkaloid biosynthesis, and phenylalanine metabolism are the

Análisis técnico de producción de tilapia Oreochromis niloticus y lechuga acrópolis Lactuca sativa en acuaponia

OpenAIRE

Rubio Cabrera, Sheila Guadalupe

2014-01-01

Se evaluó la producción de tilapia Oreochromis niloticus y lechuga romana acropolis Lactuca sativa en sistemas acuapónicos utilizando dos sistemas: recirculación de agua sin recambio (utilizando biofiltración) y sistema sin recirculación con recambio parcial de agua. El cultivo se realizó en 4 etapas. En la primera se colocaron 800 alevines de O. niloticus de 0.2 g de peso inicial en tinas plásticas de 800 L (1600 organismos/m3de agua) durante 39 días. La segunda etapa con u...

Effects of dietary Astragalus polysaccharides (APS) on growth performance, immunological parameters, digestive enzymes, and intestinal morphology of Nile tilapia (Oreochromis niloticus).

Science.gov (United States)

Zahran, Eman; Risha, Engy; Abdelhamid, Fatma; Mahgoub, Hebata Allah; Ibrahim, Tarek

2014-05-01

This work investigated the potential immunomodulatory and growth-promoting effects of Astragalus polysaccharides (APS) in Nile tilapia (Oreochromis niloticus). The dietary supplementation with APS (1500 mg/kg of diet) caused a significant increase in growth parameters (initial and final weight, weight gain (WG), specific growth rate (SGR), feed conversion ratio (FCR) and feed intake (FI), when compared to non-supplemented control basal diet. In addition, APS upregulated the phagocytic activity, the respiratory burst activity, plasma lysozyme, the bactericidal activity, superoxide dismutase (SOD), glutathione peroxidase (GPx), and amylase activity. However, it had no effect on serum nitric oxide (NO) or Malondialdehyde (MDA) levels. While APS had no effect of intestinal histology, a slight increase in the villi length was recorded. Collectively, our results indicate that dietary APS supplementation could improve the growth performance and the immune parameters of cultured tilapia fish. Copyright © 2014 Elsevier Ltd. All rights reserved.

INAA and ICP-MSHS. Metal pollutants in fish tissues Nile tilapia (Oreochromic niloticus) in Pampulha Lake, Belo Horizonte city, Minas Gerais State, Brazil

International Nuclear Information System (INIS)

Veado, M.A.R.V.; Heeren, A.O.; Arantes, I.A.; Grenier-Loustalot, M.F.; Cabaleiro, H.L.; Almeida, M.R.M.G.

2007-01-01

Pampulha Lake, Minas Gerais, Brazil, is being polluted via its tributaries, Sarandi and Ressaca. Instrumental neutron activation analysis and inductively coupled plasma mass spectrometry high resolution were applied to determine Al, As, B, Ba, Co, Cr, Cs, Cu, Fe, K, Mg, Mn, Mo, Na, P, Pb, Rb, Zn and Ti in Nile tilapia fish, Oreochromis niloticus. The organs analyzed were: intestine, spleen, heart, testicle, kidney, liver, gills and muscle. The results demonstrated relatively high concentrations of Al, Co, Cu, Fe, P and Ti in gills, Al and Cu in liver, Al in intestine and Fe in muscle and spleen. (author)

Isolated and mixed effects of diuron and its metabolites on biotransformation enzymes and oxidative stress response of Nile tilapia (Oreochromis niloticus).

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Felício, Andréia Arantes; Freitas, Juliane Silberschmidt; Scarin, Jéssica Bolpeti; de Souza Ondei, Luciana; Teresa, Fabrício Barreto; Schlenk, Daniel; de Almeida, Eduardo Alves

2018-03-01

Diuron is one of the most used herbicide in the world, and its field application has been particularly increased in Brazil due to the expansion of sugarcane crops. Diuron has often been detected in freshwater ecosystems and it can be biodegraded into three main metabolites in the environment, the 3,4-dichloroaniline (DCA), 3,4-dichlorophenylurea (DCPU) and 3,4-dichlorophenyl-N-methylurea (DCPMU). Negative effects under aquatic biota are still not well established for diuron, especially when considering its presence in mixture with its different metabolites. In this study, we evaluated the effects of diuron alone or in combination with its metabolites, DCPMU, DCPU and 3,4-DCA on biochemical stress responses and biotransformation activity of the fish Oreochromis niloticus. Results showed that diuron and its metabolites caused significant but dispersed alterations in oxidative stress markers and biotransformation enzymes, except for ethoxyresorufin-O-deethylase (EROD) activity, that presented a dose-dependent increase after exposure to either diuron or its metabolites. Glutathione S-transferase (GST) activity was significant lower in gills after exposure to diuron metabolites, but not diuron. Diuron, DCPMU and DCA also decreased the multixenobiotic resistance (MXR) activity. Lipid peroxidation levels were increased in gill after exposure to all compounds, indicating that the original compound and diuron metabolites can induce oxidative stress in fish. The integration of all biochemical responses by the Integrated Biomarker Response (IBR) model indicated that all compounds caused significant alterations in O. niloticus, but DCPMU caused the higher alterations in both liver and gill. Our findings imply that diuron and its metabolites may impair the physiological response related to biotransformation and antioxidant activity in fish at field concentrations. Such alterations could interfere with the ability of aquatic animals to adapt to environments contaminated by

Nutritional value of Prosopis juliflora Pods in feeding Nile Tilapia (Oreochromis niloticus) Fries

International Nuclear Information System (INIS)

Mabrouk, H.; Hilmi, E.; Abdullah, M.

2008-01-01

A feeding experiment was conducted to study the effect of different levels of supplemental Prosopis juliflora on growth performance, feed utilization and chemical composition of Nile tilapia (Oreochromis niloticus) fry (1.36+-0.004). Six isonitrigenous (30.46g 100g-1 crude protein) and isocalorific (0.018 NJ g-1) diets were formulated. Diet 1 (control without supplementing P. juliflora), and diets 2, 3, 4, 5 and 6 were supplemented with different levels (20, 40, 60, 80and 100 g Kg-1) of P. juliflora respectively. The results revealed that harvested gain (g fish-1) was significantly higher (P 0 .05) for fish fed 60g Kg-1 P. juliflora, while the lowest value of harvested gain was achieved with fish fed free. P. juliflora control diet. Despite that the fish fed diet (4) obtained the highest harvesting weight, weight gain, average daily gain and specific growth rate, no significant differences (P<0.05) were observed in an average daily gain (g fish-1 day-1) between fish fed diet 3, 4, 5 and 6 and in specific growth rate (% day-1) when inclusion level of P. juliflora was increased from 20 to 40 g kg-1 in diets 2 and 3 and from 80 to 100g kg-1 in diets 5 and 6, respectively. Feed intake was increased significantly (P<0.05) with in increasing P. juliflora inclusion level in the experimental diets. No significant differences were observed between the experimental fish groups in FCR in spite of the occurrence of a slight decreasing up to 80g kg-1 and PER. Protein productive value (PPV g 100g-1) and energy utilization (EUg 100g-1) were increased significantly (P<0.05) with increasing P. juliflora inclusion level in the experimental diets up to 60g kg-1 and then decreased significantly (P<0.05). Fish whole body composition of dry matter and protein were significantly (P<0.05) affected by using P. juliflora in fish diets. Fish fed diet 4 achieved the highest values of dry matter and crude protein. The results suggested that diet supplemented with 60g kg-1 P. juliflora improved

Alien fish species in upper Sakarya River and their distribution ...

African Journals Online (AJOL)

However, the fact that the flood plains have been reclaimed, excessive hunting, destruction of the ecologic balance and invasion of the area by the alien fish species threatens the fish stocks in Sakarya River. In this study, we aimed to determine the dispersion area of Carassius gibelio (Bloch, 1782), Oreochromis niloticus ...

Growth arrest specific gene 2 in tilapia (Oreochromis niloticus): molecular characterization and functional analysis under low-temperature stress.

Science.gov (United States)

Yang, ChangGeng; Wu, Fan; Lu, Xing; Jiang, Ming; Liu, Wei; Yu, Lijuan; Tian, Juan; Wen, Hua

2017-07-17

Growth arrest specific 2 (gas2) gene is a component of the microfilament system that plays a major role in the cell cycle, regulation of microfilaments, and cell morphology during apoptotic processes. However, little information is available on fish gas2. In this study, the tilapia (Oreochromis niloticus) gas2 gene was cloned and characterized for the first time. The open reading frame was 1020 bp, encoding 340 amino acids; the 5'-untranslated region (UTR) was 140 bp and the 3'-UTR was 70 bp, with a poly (A) tail. The highest promoter activity occurred in the regulatory region (-3000 to -2400 bp). The Gas2-GFP fusion protein was distributed within the cytoplasm. Quantitative reverse transcription-polymerase chain reaction and western blot analyses revealed that gas2 gene expression levels in the liver, muscle, and brain were clearly affected by low temperature stress. The results of gas2 RNAi showed decreased expression of the gas2 and P53 genes. These results suggest that the tilapia gas2 gene may be involved in low temperature stress-induced apoptosis.

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

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Mai D. Ibrahem

2010-10-01

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

Hematological parameters in Nile Tilápia, Oreochromis niloticus exposed to sub-letal concentrations of mercury

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Nilton Massuo Ishikawa

2007-07-01

Full Text Available Mercury toxicity in tilapia, Oreochromis niloticus, (Linnaeus, 1758 was investigated by the hematological parameters after long-term (14 days exposure to various Hg concentrations (0.02, 0.002, 0.0002mg/L Hg. Test groups were set up with three replicates for each concentration, plus the control group. Blood samples were collected from six individuals for each concentration at 0, 3, 7, 10 and 14 days of exposure. The hematological parameters analyzed were: total red blood cell count (RBC, hemoglobin concentration (Hb, hematocrit (Ht, mean corpuscular volume (MCV, mean corpuscular hemoglobin (MCH, mean corpuscular hemoglobin concentration (MCHC, total white blood cell count (WBC and differential leukocyte counts and total thrombocyte count (Tr. There were no significant differences among the mean hematological values at the different Hg concentrations indicating that Hg at the concentrations studied was not toxic to tilapia.A toxicidade do mercúrio foi avaliada em tilápia, Oreochromis niloticus (Linnaues, 1758 através da análise dos parâmetros hematológicos após exposição a diferentes concentrações sub-letais, durante um período de 14 dias. O bioensaio foi conduzido no laboratório de toxicologia do Instituto de Pesca, SP. Foram utilizados alevinos (12.44 ± 0.84 cm, e 27.13 ± 4.67 g e aquários com capacidade para 50 litros e preenchidos com água declorada e mais a quantidade de solução de mercúrio (HgCl2 correspondendo as seguintes concentrações: 0,02; 0,002; 0.0002 mg.L-1 Hg. Foram utilizadas 3 repetições de cada concentração e grupo controle. Amostras de sangue foram coletadas de seis animais de cada concentração nos tempos 0, 3, 7, 10 e 14 dias de exposição. Foram avaliados: a contagem de eritrócitos (RBC, concentração de hemoglobina (Hb, hematócrito (Ht, volume corpuscular médio (VCM, hemoglobina corpuscular média (HCM e concentração de hemoglobina corpuscular média (CHCM, trombócitos totais (Tr, contagem

ANALISIS KANDUNGAN MERKURI (Hg PADA IKAN NILA (Oreochromis niloticus L. BUDIDAYA KERAMBA DI SEKITAR WADUK RIAM KANAN KECAMATAN ARANIO

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Aditya Rahman

2017-10-01

Full Text Available ABSTRACTThis study aims to determine the content of heavy metals mercury contained in the fish Tilapia (Oreochromis niloticus L. aquaculture cages around the Riam Kanan reservoir and compare it with quality standards based on the Decree of the Head of BPOM No. HK.00.06.1.52.4011 about the maximum limit of metal contamination in food, especially in fish. This study was conducted from September to December 2011. Sampling was conducted at three stations covering the village of Tiwingan Baru, Tiwingan Lama dan Aranio in the Aranio district. Sampling was done by purposive sampling method or sampling intentionally with certain considerations that are considered important. Mercury analysis performed using Atomic Absorption Spectrophotometer (AAS instrument. Result showed that the average content of mercury in sediment samples at the first station of 0,0262 mg/kg; the second station of 0,1489 mg/kg and not detected at the third station, the content is still below the set threshold. The content of mercury in water samples of Riam Kanan reservoir at all stations are still below the threshold of water quality standards according to Government Regulation No. 82 of 2001. Result on the mercury content of Tilapia fish meat samples at all stations are still below the standards threshold based on the Decree of the Head of BPOM about the maximum limit of metal contamination in food, especially in fish.

Influence of Cooking (Microwaving and Broiling) on Cylindrospermopsin Concentration in Muscle of Nile Tilapia (Oreochromis niloticus) and Characterization of Decomposition Products.

Science.gov (United States)

Prieto, Ana I; Guzmán-Guillén, Remedios; Valderrama-Fernández, Rocío; Jos, Ángeles; Cameán, Ana M

2017-05-26

Cylindrospermopsin (CYN) has become increasingly important as a freshwater algal toxin, showing cytotoxic effects. This toxin is able to bioaccumulate in freshwater food webs, representing a serious human health problem. Normally, fish is cooked before consumption, and CYN concentration can be altered. For the first time, the effects of microwaving and broiling for 1 and 2 min on CYN concentration and its decomposition products in fish muscle ( Oreochromis niloticus ) contaminated in the laboratory were investigated, using UPLC-MS/MS and Orbitrap. The results show that cooking the fish reduced unconjugated CYN levels by 11, 10 and 15% after microwaving for 1 and 2 min, and broiling for 2 min, respectively, compared to control fish. Different CYN decomposition products with m / z 416.1234 (7-epi-CYN) and m / z 336.16663 (diasteroisomers C-3A, C-3C, C-3D, C-3E, C-3F) are generated in fish samples submitted to cooking. Based on the relative abundance of the decomposition products, the possible degradation pathways taking place by microwaving may be through the formation of 7-epi-CYN and m / z 336.16663 compounds, whereas in the case of broiling the last route is the only one observed in this study. The influence of cooking and the toxicity characterization of the degradation products generated in CYN-contaminated fish are of importance for more realistic risk evaluation related to their consumption.

Preliminary studies in rice-fish culture in a rainfed lowland ecology ...

African Journals Online (AJOL)

Mixed farms of rice and fish are yet to receive attention in Ghana, despite lowland rice being grown under inundation in most areas nationwide. In a preliminary study, Nile tilapia (Oreochromis niloticus) was successfully cultured in a rainfed lowland rice farm, although no additional care was provided for fishes. The highest ...

Effect of probiotic and sand filtration treatments on water quality and growth of tilapia (Oreochromis niloticus) and pangas (Pangasianodon hypophthalmus) in earthen ponds of southern Bangladesh

DEFF Research Database (Denmark)

Mahmud, Sultan; Ali, Mohammad Lokman; Alam, Md Ariful

2016-01-01

Effects of water treatment by two probiotic products (PondPlus® and AquaPhoto®) and sand filtration were studied on growth performance of tilapia (Oreochromis niloticus) and pangas (Pangasianodon hypophthalmus) stocked at tilapia:pangas ratio of 5:3 in traditional earthen ponds in Bangladesh....... The fish were stocked at a density of 20,000 fish ha−1 and reared for 7 months. Compared to untreated ponds, treatments of probiotic products or sand filtration in earthen ponds resulted in a higher O2 content, higher water transparency, less ammonium, and fewer cyanobacteria. Weight gain for individual...... tilapia was lowest in the AquaPhoto-treated ponds (177 g), while similar gains (188–194 g) occurred in the other ponds. For pangas, the lowest weight gain (627 g) was obtained in the sand filter-treated ponds, as compared to 690–797 g in the other ponds. Thus, a general positive effect from the treatments...

Production algale et consommation par le Tilapia, Oreochromis niloticus L., au Lac Muhazi (Rwanda. Résumé de thèse de doctorat

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Mukankomeje, R.

1992-01-01

Full Text Available Algal production and consumption by the Tilapia Oreochromis niloticus L., in Lake Muhazi (Rwanda. The article describes shortly the objectives of a Food Early Warning System (FEWS project, as well as its organisation. The specifie case of Somalia, where the project had to evolve in increasingly difficult situations, and the solutions used so as to preserve the output, are described.

Preliminary studies in rice-fish culture in a rainfed lowland ecology ...

African Journals Online (AJOL)

Preliminary studies in rice-fish culture in a rainfed lowland ecology in Ghana. PKA Dartey, RK Bam, J Ofori. Abstract. Mixed farms of rice and fish are yet to receive attention in Ghana, despite lowland rice being grown under inundation in most areas nationwide. In a preliminary study, Nile tilapia (Oreochromis niloticus) was ...

Genetic characterization of a betanodavirus isolated from a clinical disease outbreak in farm-raised tilapia Oreochromis niloticus (L.) in Thailand.

Science.gov (United States)

Keawcharoen, J; Techangamsuwan, S; Ponpornpisit, A; Lombardini, E D; Patchimasiri, T; Pirarat, N

2015-01-01

Betanodavirus infection was diagnosed in larvae of farm-raised tilapia Oreochromis niloticus (L.), in central Thailand. Extensive vacuolar degeneration and neuronal necrosis were observed in histological sections with positive immunohistochemical staining for betanodavirus. Molecular phylogenetic analysis was performed based on the nucleotide sequences (1333 bases) of the capsid protein gene. The virus strain was highly homologous (93.07-93.88%) and closely related to red-spotted grouper nervous necrosis virus (RGNNV). © 2013 John Wiley & Sons Ltd.

Heritability and genotype by environment interaction estimates for harvest weight, growth rate, and shape of Nile tilapia (Oreochromis niloticus) grown in river cage and VAC in Vietnam

NARCIS (Netherlands)

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

2013-01-01

Harvest weight has been the main selected trait for the GIFT strain of Nile tilapia (Oreochromis niloticus). However, growth rate and body shape are traits of increasing interest. In the Mekong Delta of Vietnam, intensive river-cage culture and low-input ponds are the most important production

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%.

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. Copyright © 2016 Elsevier Inc. All rights reserved.

Pig-duck-fish-azolla integration in La Union, Philippines

OpenAIRE

Gavina, L.D.

1994-01-01

Three studies on pig-duck-fish-azolla integration were conducted simultaneously in La Union, Philippines. Growth performance of pigs and ducks as affected by different levels of azolla meal in their feed, and that of tilapia (Oreochromis niloticus) under varying stocking rates are presented and discussed.

Effects of replacing soybean meal with rubber seed meal on growth, antioxidant capacity, non-specific immune response, and resistance to Aeromonas hydrophila in tilapia (Oreochromis niloticus × O. aureus).

Science.gov (United States)

Deng, Junming; Mai, Kangsen; Chen, Liqiao; Mi, Haifeng; Zhang, Lu

2015-06-01

This study evaluated the effects of replacing soybean meal (SBM) with rubber seed meal (RSM) on growth, antioxidant capacity, non-specific immune response and resistance to Aeromonas hydrophila in tilapia (Oreochromis niloticus × Oreochromis aureus). Five experimental diets were formulated with 0 (control), 10, 20, 30, and 40% RSM replacing graded levels of SBM, respectively. Fish were fed one of the five experimental diets for eight weeks, and then challenged by A. hydrophila via intraperitoneal injection and kept for seven days. Dietary RSM inclusion level up to 30% did not affect the weight gain and daily growth coefficient, whereas these were depressed by a further inclusion. Fish fed diet with 40% RSM showed the lowest serum total antioxidant capacity, lysozyme, alternative complement pathway, respiratory burst and phagocytic activities. Dietary RSM inclusion gradually depressed the post-challenge survival rate, and that was significantly lower in fish fed diet with 40% RSM compared to fish fed the control diet. Conversely, the inclusion of RSM generally increased the serum total cholesterol level, the plasma alanine aminotransferase and aspartate aminotransferase activities, and these were significantly higher in fish fed diet with 40% RSM compared to fish fed the control diet. The results indicated that RSM can be included at level up to 30% in diet for tilapia without obvious adverse effects on the growth, antioxidant capacity, non-specific immune response and resistance to A. hydrophila infection, whereas these were depressed by a further inclusion. Copyright © 2015 Elsevier Ltd. All rights reserved.

Effects of palm kernel cake (PKC on growth performance, blood components and liver histopathology of sex reversed red tilapia (Oreochromis niloticus

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Sukasem, N.

2007-09-01

Full Text Available Effects of Palm Kernel Cake (PKC on growth performance, blood components and liver histopathology of sex- reversed red tilapia Oreochromis niloticus were studied using seven isocaloric diets (3400 kCal/ kg containing different levels of protein and PKC. Diet 1, 2 and 3 contained 20% protein with the supplementation of 15, 30 and 45% PKC, respectively. Diets 4, 5 and 6 contained 24% protein in combinationwith the same PKC supplemention levels mentioned above, and diet 7 was commercial feed containing 20% protein as a control diet. Experimental diets were fed to experimental fish of 48.65 g initial average body weight cultured in floating cages (3 cages/diet for 10 weeks. Fish fed diets containing higher protein (24%; diets 4, 5 and 6 had significantly better growth performance (p<0.05 than those fed lower protein (20%; diets 1, 2 and 3. Considering the effect of PKC, fish fed diet 5 (Prot. 24%, PKC 30% gave the greatest growth performance (p<0.05 and all the PKC-fed groups had significantly higher growth than fish fed control diet. There was evidence that supplementation of PKC in fish feed ranging from 15 to 45% had no effect to the survival rate, blood components, or hepatocytic cells of tilapia. However, liver tissue showed higher numbers of lipid droplets in fish fed diet contained 45% PKC (diets 3 and 6. For the production cost, all test diets with PKC supplementation had significantly higher price (p<0.05 than commercial feed. However, when considering the feeding cost per unit of fish production, fish reared with PKC supplemented diets had significantly lower cost (p<0.05 than fish fed commercial feed.

Mechanical and thermal properties of irradiated films based on Tilapia (Oreochromis niloticus) proteins

Energy Technology Data Exchange (ETDEWEB)

Sabato, S.F. [Radiation Technology Center, IPEN-CNEN/SP, Av. Lineu Prestes 2242, 05508 900 Sao Paulo, SP (Brazil)], E-mail: sfsabato@ipen.br; Nakamurakare, N.; Sobral, P.J.A. [Food Engineering Department, ZEA/FZEA/USP, Av. Duque de Caxias Norte 225, 13635 900 Pirassununga, SP (Brazil)

2007-11-15

Proteins are considered potential material in natural films as alternative to traditional packaging. When gamma radiation is applied to protein film forming solution it resulted in an improvement in mechanical properties of whey protein films. The objective of this work was the characterization of mechanical and thermal properties of irradiated films based on muscle proteins from Nile Tilapia (Oreochromis niloticus). The films were prepared according to a casting technique with two levels of plasticizer: 25% and 45% glycerol and irradiated in electron accelerator type Radiation Dynamics, 0.550 MeV at dose range from 0 to 200 kGy. Thermal properties and mechanical properties were determined using a differential scanning calorimeter and a texture analyzer, respectively. Radiation from electron beam caused a slightly increase on its tensile strength characteristic at 100 kGy, while elongation value at this dose had no reduction.

Mechanical and thermal properties of irradiated films based on Tilapia (Oreochromis niloticus) proteins

International Nuclear Information System (INIS)

Sabato, S.F.; Nakamurakare, N.; Sobral, P.J.A.

2007-01-01

Proteins are considered potential material in natural films as alternative to traditional packaging. When gamma radiation is applied to protein film forming solution it resulted in an improvement in mechanical properties of whey protein films. The objective of this work was the characterization of mechanical and thermal properties of irradiated films based on muscle proteins from Nile Tilapia (Oreochromis niloticus). The films were prepared according to a casting technique with two levels of plasticizer: 25% and 45% glycerol and irradiated in electron accelerator type Radiation Dynamics, 0.550 MeV at dose range from 0 to 200 kGy. Thermal properties and mechanical properties were determined using a differential scanning calorimeter and a texture analyzer, respectively. Radiation from electron beam caused a slightly increase on its tensile strength characteristic at 100 kGy, while elongation value at this dose had no reduction

Effects of Wheat Naturally Contaminated with Fusarium Mycotoxins on Growth Performance and Selected Health Indices of Red Tilapia (Oreochromis niloticus × O. mossambicus)

Science.gov (United States)

Tola, Siriporn; Bureau, Dominique P.; Hooft, Jamie M.; Beamish, Frederick W. H.; Sulyok, Michael; Krska, Rudolf; Encarnação, Pedro; Petkam, Rakpong

2015-01-01

An 8-week feeding trial was conducted to examine effects of wheat naturally contaminated with Fusarium mycotoxins (deoxynivalenol, DON 41 mg·kg−1) on growth performance and selected health indices of red tilapia (Oreochromis niloticus × O. mossambicus; initial weight = 4.3 g/fish). Five experimental diets were formulated by replacement of clean wheat with naturally contaminated wheat resulting in graded levels of DON and zearalenone (ZEN) (Diet 1 0.07/0.01, Diet 2 0.31/0.09, Diet 3 0.50/0.21, Diet 4 0.92/0.37 and Diet 5 1.15/0.98 mg·kg−1). Groups of 50 fish were randomly allocated into each of 20 aquaria and fed to near-satiety for eight weeks. Growth rate, feed intake and feed efficiency of fish fed the experimental diets decreased linearly with increasing levels of Fusarium mycotoxins (p mycotoxins, especially DON, no biochemical and histopathological parameters measured in blood and liver appeared affected by Fusarium mycotoxin concentrations of diets (p > 0.05). Though there was no clear evidence of overt DON toxicity to red tilapia, it is recommended that feed ingredients should be screened for Fusarium mycotoxin contamination to ensure optimal growth performance. PMID:26035489

The influence of ration size on energetics and nitrogen retention in tilapia (Oreochromis niloticus)

DEFF Research Database (Denmark)

Skov, Peter Vilhelm; Duodu, Collins Prah; Adjei-Boateng, Daniel

2017-01-01

with ration size, feed conversion and protein retention were most efficient at ration sizes of 3%. Although the magnitude of the SDA response following feeding also increased with ration size, this was not proportionate to meal size. Therefore the metabolic cost of meal processing (SDA coefficient) was found......Proper nutrient management is essential for the environmental sustainability of aquaculture. While increasing daily rations generally may lead to improved growth rates, this does not necessarily mean that nutrients are utilized more efficiently. To investigate how ration size affects partitioning...... 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...

Biochemical and cellularchanges in Oreochromis niloticus related to the water pollution of a degraded river - doi: 10.4025/actascibiolsci.v35i3.13207

Directory of Open Access Journals (Sweden)

Ary Gomes da Silva

2013-08-01

Full Text Available The effects of polluted water at three sites in the Marinho River, Brazil, on Oreochromis niloticus (Nile tilápia were investigated using histological, hematological and biochemical approaches. Fish exposed to the impacted water demonstrated that histological changes in gills were accompanied by nuclear and micronuclei abnormalities in cells. The activity of liver and plasma biomarkers (alkaline phosphatase (ALP, acid phosphatase (ACP, alanine aminotransferase (ALT, aspartate aminotransferase (AST and liver glutathione S-transferase (GST showed an expressive change due to the. The results were also correlated with the highest levels of Cu+2, Zn+2 and Mn+2 in the water. The data of this study evidenced the importance of using a set of biomarkers to quantify pollution in lentic ecosystems. Additionally, histological analyses of gills and erythrocytes have proven to be an important instrument for signaling the impact of pollutants in rivers.  

Aluminium sulfate exposure: A set of effects on hydrolases from brain, muscle and digestive tract of juvenile Nile tilapia (Oreochromis niloticus).

Science.gov (United States)

Oliveira, Vagne Melo; Assis, Caio Rodrigo Dias; Costa, Helane Maria Silva; Silva, Raquel Pereira Freitas; Santos, Juliana Ferreira; Carvalho, Luiz Bezerra; Bezerra, Ranilson Souza

2017-01-01

Aluminium is a major pollutant due to its constant disposal in aquatic environments through anthropogenic activities. The physiological effects of this metal in fish are still scarce in the literature. This study investigated the in vivo and in vitro effects of aluminium sulfate on the activity of enzymes from Nile tilapia (Oreochromis niloticus): brain acetylcholinesterase (AChE), muscle cholinesterases (AChE-like and BChE-like activities), pepsin, trypsin, chymotrypsin and amylase. Fish were in vivo exposed during 14days when the following experimental groups were assayed: control group (CG), exposure to Al 2 (SO 4 ) 3 at 1μg·mL -1 (G1) and 3μg·mL -1 (G3) (concentrations compatible with the use of aluminium sulfate as coagulant in water treatment). In vitro exposure was performed using animals of CG treatment. Both in vivo and in vitro exposure increased cholinesterase activity in relation to controls. The highest cholinesterase activity was observed for muscle BChE-like enzyme in G3. In contrast, the digestive enzymes showed decreased activity in both in vivo and in vitro exposures. The highest inhibitory effect was observed for pepsin activity. The inhibition of serine proteases was also quantitatively analyzed in zymograms using pixel optical densitometry as area under the peaks (AUP) and integrated density (ID). These results suggest that the inhibition of digestive enzymes in combination with activation of cholinesterases in O. niloticus is a set of biochemical effects that evidence the presence of aluminium in the aquatic environment. Moreover, these enzymatic alterations may support further studies on physiological changes in this species with implications for its neurological and digestive metabolisms. Copyright © 2016 Elsevier Inc. All rights reserved.

Edad y crecimiento del híbrido de tilapia Oreochromis niloticus x Oreochromis aureus (Perciformes: Cichlidae en la represa “Zimapán” Hidalgo, México

Directory of Open Access Journals (Sweden)

M. A. Gómez-Ponce

2011-06-01

Full Text Available La edad y crecimiento de la tilapia Oreochromis niloticus x Oreochromis aureus fueron determinados por medio de la lectura de escamas. Un total de 382 individuos fueron capturados mediante el uso de redes agalleras y atarrayas. Ocho recolectas mensuales se llevaron a cabo entre septiembre 2003-mayo 2004; se registraron los datos de longitud estándar en cm. (Le, el peso total en g (Pt y se obtuvieron muestras de escamas para registrar el largo de la escama en mm. (Lesc y el número de anillos de crecimiento formados. Las tallas y pesos de recolecta variaron entre 38 a 232mm (Le y de 8.7 a 311.9g de peso total (Pt respectivamente. El recuento de los anillos anuales en escamas, permitió establecer cuatro grupos de edad, siendo el grupo de edad 2 el más representativo, con un 34.3% de la población muestreada. El cálculo de los incrementos marginales del crecimiento mensual de las escamas, sugirió la formación de dos anillos, uno de ellos se forma en los meses de noviembre-enero y otro en los meses de abril-mayo, los cuales coinciden con la época de bajas temperaturas y de madurez gonádica respectivamente. Los parámetros de crecimiento quedaron establecidos en: L∞=281.1mm, W∞=877.1g, K=0.33 y T0=0.88/año. Las curvas de crecimiento en longitud y peso se describieron mediante las ecuaciones de von Bertalanffy: Le=28.11 [1- e-0.33(t+0.88] y Pt=877.17 [1-e-0.33(t+0.88]³. Finalmente, se concluyó que los peces que se explotan en la represa mediante captura comercial presentan entre un año y año y medio de edad.Age and growth of the hybrid tilapia Oreochromis niloticus x Oreochromis aureus (Perciformes: Cichlidae in the dam “Zimapan” Mexico. Studies on age and growth in fishes are essential to establish models on population dynamics. The previos issues were determined in this study by scale growth analyses. Between September 2003 and May 2004, 382 organisms were captured using gill and atarraya nets. Eight samples were developed every

Protective effect of hydroferrate fluid, MRN-100, against lethality and hematopoietic tissue damage in γ-radiated Nile tilapia, Oreochromis niloticus

International Nuclear Information System (INIS)

Ghoneum, Mamdooh; Elbaghdady, Heba Allah M.; El-Shebly, Abdallah A.; Pan, Deyu; Assanah, Edward; Lawson, Greg

2013-01-01

Hydroferrate fluid, MRN-100, an iron-based compound derived from bivalent and trivalent ferrates, is a potent antioxidant compound. Therefore, we examined the protective effect of MRN-100 against γ-radiation-induced lethality and damage to hematopoietic tissues in fish. A total of 216 Nile tilapia fish (Oreochromis niloticus) were randomly divided into four groups. Group 1 served as a control that was administered no radiation and no MRN-100 treatment. Group 2 was exposed only to γ-radiation (15 Gy). Groups 3 and 4 were pre-treated with MRN-100 at doses of either 1 ml/l or 3 ml/l in water for 1 week, and subsequently exposed to radiation while continuing to receive MRN-100 for 27 days. The survival rate was measured, and biochemical and histopathological analyses of hematopoietic tissues were performed for the different treatment groups at 1 and 4 weeks post-radiation. Exposure to radiation reduced the survival rate to 27.7%, while treatment with MRN-100 maintained the survival rate at 87.2%. In addition, fish exposed to γ-radiation for 1 week showed a significant decrease in the total number of white blood cells (WBCs) and red blood cells (RBCs) series. However, treatment with MRN-100 protected the total WBC count and the RBCs series when compared with irradiated fish. Furthermore, significant histological lesions were observed in the hepatopancreas, spleen and gills of irradiated fish. However, treatment with MRN-100 protected the histopathology of various organs. We conclude that MRN-100 is a radioprotective agent in fish and may be useful as an adjuvant treatment to counteract the adverse side effects associated with radiation exposure. (author)

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

Science.gov (United States)

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

2003-01-01

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

The identification of plankton, water quality, blood cell, and histology in culture pond of tilapia Oreochromis niloticus which infected by viral nervous necrosis (VNN)

Science.gov (United States)

Yanuhar, U.; Rahayu, D. T.; Musa, M.; Arfiati, D.

2018-04-01

Currently, Viral Nervous Necrotic (VNN) is not only attacking the marine fish but also the freshwater fish like tilapia (Oreochromis niloticus). The aims of study to identify the type of plankton, water quality status, blood cell status, also histology of VNN infected tilapia obtained in culture ponds. The methods included plankton identification and water quality analysis from the infected fish pond in the Krakal, Blitar. The quality of blood cells and the histology of tilapia infected by VNN observed using a microscope with Hematoxylin-Eosin staining. The result show plankton in a fish pond of infected tilapia includes 3 divisions: Chlorophyta, Cyanophyta, and Bacillariophyta and 2 phyla: Arthropoda, and Rotifera. The values of erythrocyte, hematocrit, and hemoglobin were smaller than normal tilapia, however, the leukocyte and macronucleus values of VNN-infected fish were higher than normal fish. The fish histology shows the vacuolation in the brain and eyes tissue. The water quality of the culture pond have the temperature, pH, turbidity, DO, CO2, NO3, PO4, TOM in the range of 30-32°C 7.0-9.0; 25cm; 6.082–7.44mg/L 3.98–9.08mg/L 1.039–1.139 mg/L; 0.051-0.054mg/L; and 11.377-13.905mg/L, respectively. VNN causing high leukocyte and macronuclei and the damaging in brain and eyes tissue in infected tilapia.

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.

Depletion study, withdrawal period calculation and bioaccumulation of sulfamethazine in tilapia (Oreochromis niloticus) treated with medicated feed.

Science.gov (United States)

Nunes, Kátia S D; Vallim, José H; Assalin, Márcia R; Queiroz, Sonia C N; Paraíba, Lourival C; Jonsson, Claudio M; Reyes, Felix G R

2018-04-01

The residue depletion of sulfamethazine (SMZ) was evaluated in tilapia (Oreochromis niloticus) after 11 days of administration of medicated feed containing SMZ, at the dose of 422 mg/kg body weight (bw). The determination of SMZ in feed and tilapia fillet was carried out using the QuEChERS approach for sample preparation, and high performance liquid chromatography with diode array detector (HPLC-DAD) and ultra-high performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-QToF-MS) for quantitation, respectively. Both methods were validated based on international and Brazilian guidelines and shown to be suitable for the intended purposes. The withdrawal period to reach the maximum residue level (MRL) of 100 μg/kg, according to the European Union (EU) legislative framework to all substances belonging to the sulfonamide (SA) group (EU, 2010), was 10 days (260 °C-day). After treatment, the maximum level of SMZ accumulation in the tilapia muscle was 1.6 mg/kg. SMZ was shown to be quickly excreted by tilapia. Thus, considering the acceptable daily intake of SMZ established by the Codex Commission (0-0.05 mg/kg bw), and a factor of 5 times the upper amount of fish consumption in Brazil (38 kg/year), this study showed that there is a low risk of adverse effects to consumers. This study offers subsidies not only for the establishment of public policies with regard to the use of veterinary drugs currently not allowed in a country by their legal legislative framework for fish farming, but also to fish producers for the proper handling to ensure safe fish fillets. Copyright © 2018 Elsevier Ltd. All rights reserved.

Effects of shrimp head meal in the diets on growth, feed efficiency and pigmentation of sex-reversed red tilapia, Oreochromis niloticus x O. mossambicus

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Pimolrat, P.

2006-09-01

Full Text Available Shrimp head meal (SHM was used to replace fish meal as a protein source in practical diets for sexreversed red tilapia (Oreochromis niloticus x O. mossambicus at 0, 25, 50, 75 and 100% of fish meal protein or 0, 6.92, 13.84, 20.76 and 27.68% by weight of diet respectively. Catfish feed that contained protein content 37.22±0.10% was included as a reference diet. The experimental diets were fed to the fish with mean initial weight of 3.13±0.05 g for 8 weeks in 70 l aquaria. The results showed that weight gain and specific growth rate of fish fed 50% of fishmeal protein replacement or diet 3 was not significant by different from those of fish on control diet (p>0.05. The data of feed intake, feed conversion ratio and productive protein value of fish fed diet 3 were equal to those fed control diet (p>0.05. The lowest growth rate and feed efficiency showed on fish fed 100% of fishmeal protein replacement. The production cost of fish fed diet 3 was equal to those fed the control diet and the reference diet (p>0.05. Total carotenoid content in fish skin was significantly highest (p<0.05 in fish fed 100% of fishmeal protein replacement diet. The result indicates that the use of SHM at the level of 50% replacement or 13.84% by weight of diet is a potential protein source in sex-reversed red tilapia diet.

Cathepsin activities and thermal properties of Nile tilapia (Oreochromis niloticus meat during ambient storage

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Tulakhun Nonthaput

2017-06-01

Full Text Available Understanding the postmortem changes at ambient aquatic temperature can be useful for estimating the time of death in environmental forensic studies when little information is available. Muscle degradation was investigated in Nile tilapia (Oreochromis niloticus in terms of the specific activities of cathepsins (B, H and L and the scavenging activities and thermal transition properties of myosin and actin, to assess postmortem changes with time (0, 1, 2, 4, 8, 12, 24 and 48 h after death. The study results are relevant to ambient temperatures in Thailand, (about 30 °C. The specific activities of the three cathepsin enzymes increased significantly with postmortem time (p < 0.05 and had a highly significant positive relationship (r = 0.987−0.997, p < 0.01, n = 32. Cathepsin H had the lowest specific activity and exhibited a different type of time profile. Its lowest specific activity was observed at 8 h, which indicated a significant role at this point in time after death. The radical scavenging activities substantially decreased with the time since death, especially within the first 1 h, while no changes occurred from 2 to 8 h, or from 12 to 24 h. The thermal properties of myosin and actin were observed up to a 24 h delay. The degradation of each protein fluctuated with the delay time; actin was more sensitive to postmortem delay than myosin. Overall, the findings from the current study might be used as primary data to estimate the time of death of an aquatic animal. A potential application is for environmental forensics in relation to fish kill events associated with pollution crimes or the mass death of exported fish under transportation insurance, as well as in animal cruelty investigations.

Toxicidade aguda e efeitos histopatológicos do herbicida diquat na brânquia e no fígado da tilápia nilótica (Oreochromis niloticus = Acute toxicity and histopathologic effects of diquat herbicide on the gill and liver of nile tilapia (Oreochromis niloticus

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Matheus Nicolino Peixoto Henares

2008-01-01

Full Text Available A concentração letal 50% e os efeitos histopatológicos do herbicida diquat para a tilápia nilótica (Oreochromis niloticus foram avaliados em três experimentos. Os peixes foram expostos às concentrações de 0; 25; 30; 35; 40; 45; 50; 55; e 60 mg de diquat L-1 e a histologia da brânquia e do fígado foi avaliada nos peixes sobreviventes. A CL (I 50-96h do diquat estimada foi de 37,28 mg L-1, com limite inferior de 33,12 mg L-1 e superior de 41,44mg L-1. No tratamento com 30, 35 e 40 mg L-1, ocorreram início de fusão apical das lamelas secundárias; com 45 e 50 mg L-1 ocorreram congestão nas lamelas primárias e no tratamento com 55 mg L-1, ocorreu congestão sangüínea nas lamelas secundárias. O fígado dos peixes dos tratamentos controle, 30 e 35 mg L-1 estavam com organização cordonal dos hepatócitos. Nos tratamentos com 40 e 45 mg L-1, ocorreram hipertrofia dos hepatócitos; com 50 e 55 mg L-1 ocorreram fusão celular e presença de vacúolos. O diquat apresentoubaixo risco de intoxicação à tilápia nilótica e as alterações histopatológicas mais severas ocorreram somente nas concentrações mais elevadas.The lethal concentration of 50% (LC (I 50-96h and the histopathologic effects of diquat herbicide on Nile tilapia (Oreochromis niloticus fish were evaluated in three experiments. The fishes were exposed to concentrations of 0, 25, 30, 35, 40, 45, 50, 55 and 60 mg diquat L-1, and gill and liver histology were evaluated in the surviving fishes. The estimated LC (I (50-96h of diquat was37.28 mg L-1, with lower limits of 33.12 mg L-1 and upper limits of 41.44 mg L-1. In the treatment with 30, 35 and 40 mg L-1, signs of apical fusion of the secondary lamellae were observed; with 45 and 50 mg L-1, congestion of the primary lamellae was observed; in thetreatment with 55 mg L-1, congestion of blood vessels on secondary lamellae took place. The livers of fishes in treatments with 0, 25, 30 and 35 mg L-1 showed cordonal

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.

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

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Ling Wei

2016-02-01

Full Text Available 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.

Determination of selenium toxicity to Oreochromis niloticus based on hematological parameters=Determinação da toxicidade do Selênio por meio de análises hematológicas em Oreochromis niloticus

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Silmara Regina Siqueira

2012-04-01

Full Text Available Selenium (Se is described as an essential micronutrient and participates in different biological functions, as the antioxidant defense systems maintenance and regulation. However, when in high concentrations, Se may cause toxic effects as well as hematological changes in fish. The aim of the present study was to determine the toxicity of selenium in the form of sodium selenate (Na2Se6+O4 in Oreochromis niloticus based on hematological parameters, after exposure to different concentrations (0.01, 0.14 and 1.4 mg Se6+ L-1. The erythrocytic and leukocytic series were examined over 14 days at intervals of 0, 3, 5, 7,10 and 14 days. The erythrocytic series showed significant alterations in the first 7 days, including the control group. Neutrophils and monocytes showed variations in the first 3 days at a concentration of 1.40 mgSe6+ L-1 characterizing an acute response. The total number of leukocytes was different in relation to time zero on all Se concentrations. The thrombocyte count also differed statistically from time zero and control in the first 3 days at 0.14 mgSe6+ L-1. These results indicate that different concentrations induce an acute response with diminution of total leukocytes, neutrophilia, monocytosis and thrombocytosis.O selênio (Se é descrito como um micronutriente essencial e participa de diversas funções biológicas. No entanto, quando em concentrações elevadas, o Se pode causar efeitos tóxicos, bem como alterações hematológicas em peixes. O objetivo do presente estudo foi determinar a toxicidade do selênio na forma de Selenato de sódio (Na2Se6+O4 em Oreochromis niloticus com base em parâmetros hematológicos, após a exposição a diferentes concentrações (0,01, 0,14 e 1,4 mg + Se6+ L-1. A série eritrocitária e leucocitária foram examinadas por 14 dias, em intervalos de 0, 3, 5, 7,10 e 14 dias. A série eritrocítica mostrou alterações significativas nos primeiros 7 dias, incluindo o grupo controle. Neutr

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

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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.

Eficácia do mentol como anestésico para juvenis de tilápia-do-nilo (Oreochromis niloticus)

OpenAIRE

Simões,L.N.; Gomes,L.C.

2009-01-01

Em três experimentos, testou-se a eficiência do mentol como anestésico para a tilápia-do-nilo (Oreochromis niloticus), por meio da avaliação de eventos comportamentais, da verificação da margem de segurança do anestésico e das respostas de estresse. No primeiro experimento, foram testadas seis diferentes concentrações de mentol para avaliar o tempo de indução à anestesia. No segundo, foram realizados dois testes com o objetivo de verificar a margem de segurança do anestésico. No terceiro, ava...

Effects of dietary grape seed proanthocyanidins on growth performance, some serum biochemical parameters and body composition of tilapia (Oreochromis niloticus fingerlings

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Shao Wei Zhai

2014-07-01

Full Text Available The present study was performed with tilapia (Oreochromis niloticus to evaluate the effects of diet supplementation with grape seed proanthocyanidins (GSPs on fish growth performance, some serum parameters and body composition. Three hundred tilapia fingerlings with the initial average body weight of 9.50±1.25 g were randomly divided into five treatment groups with four replicates in each group and 15 fish in each replicate. The dietary GSPs levels of five treatment groups were 0 (control group, 200, 400, 600, and 800 mg/kg, respectively. The trial period was 49 days. Growth performance parameters were significantly improved by GSPs supplementation (P<0.05, while survival rates were similar among all groups (P>0.05. Serum parameter results showed that activities of aminotransferase aspartate in 200 and 400 mg/kg GSPs groups and alanine aminotransferase in 400 mg/kg GSPs group were lowered significantly (P<0.05. Levels of triglyceride and total cholesterol (except 200 mg/kg GSPs group were significantly lowered, while lysozyme activity and albumin level were significantly higher in fish of GSPs supplemented groups, independently from the level of supplementation. The highest crude protein level and lowest crude lipid level were found in fish of all GSPs supplemented groups, while levels of moisture and ash in fish of all groups were similar (P>0.05. The results indicated that dietary 200 mg/kg GSPs could exert beneficial effects on growth and body composition of tilapia fingerlings, and ameliorate serum biochemistry parameters related to health status.

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.

Effects of bamboo substrate and supplemental feeding on growth and production of hybrid red tilapia fingerlings (Oreochromis mossambicusxOrechromis niloticus)

NARCIS (Netherlands)

Keshavanath, P.; Gangadhar, B.; Ramesh, T.J.; Dam, van A.A.; Beveridge, M.C.M.; Verdegem, M.C.J.

2004-01-01

Periphyton growing on artificial substrates can increase the production of herbivorous fish in aquaculture ponds. Periphyton may be an alternative or a complement for supplemental feed in fingerling production. Growth and production of hybrid red tilapia (Oreochromis mossambicus x Oreochromis

Effects of Wheat Naturally Contaminated with Fusarium Mycotoxins on Growth Performance and Selected Health Indices of Red Tilapia (Oreochromis niloticus × O. mossambicus

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Siriporn Tola

2015-05-01

Full Text Available An 8-week feeding trial was conducted to examine effects of wheat naturally contaminated with Fusarium mycotoxins (deoxynivalenol, DON 41 mg·kg−1 on growth performance and selected health indices of red tilapia (Oreochromis niloticus × O. mossambicus; initial weight = 4.3 g/fish. Five experimental diets were formulated by replacement of clean wheat with naturally contaminated wheat resulting in graded levels of DON and zearalenone (ZEN (Diet 1 0.07/0.01, Diet 2 0.31/0.09, Diet 3 0.50/0.21, Diet 4 0.92/0.37 and Diet 5 1.15/0.98 mg·kg−1. Groups of 50 fish were randomly allocated into each of 20 aquaria and fed to near-satiety for eight weeks. Growth rate, feed intake and feed efficiency of fish fed the experimental diets decreased linearly with increasing levels of Fusarium mycotoxins (p < 0.05. Although growth depression was associated with feeding diets naturally contaminated with Fusarium mycotoxins, especially DON, no biochemical and histopathological parameters measured in blood and liver appeared affected by Fusarium mycotoxin concentrations of diets (p > 0.05. Though there was no clear evidence of overt DON toxicity to red tilapia, it is recommended that feed ingredients should be screened for Fusarium mycotoxin contamination to ensure optimal growth performance.

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.

Marine Collagen Peptides from the Skin of Nile Tilapia (Oreochromis niloticus): Characterization and Wound Healing Evaluation.

Science.gov (United States)

Hu, Zhang; Yang, Ping; Zhou, Chunxia; Li, Sidong; Hong, Pengzhi

2017-03-30

Burns can cause tremendous economic problems associated with irreparable harm to patients and their families. To characterize marine collagen peptides (MCPs) from the skin of Nile tilapia ( Oreochromis niloticus ), molecular weight distribution and amino acid composition of MCPs were determined, and Fourier transform infrared spectroscopy (FTIR) was used to analyze the chemical structure. Meanwhile, to evaluate the wound healing activity, in vitro and in vivo experiments were carried out. The results showed that MCPs prepared from the skin of Nile tilapia by composite enzymatic hydrolysis were composed of polypeptides with different molecular weights and the contents of polypeptides with molecular weights of less than 5 kDa accounted for 99.14%. From the amino acid composition, the majority of residues, accounting for over 58% of the total residues in MCPs, were hydrophilic. FTIR indicated that the main molecular conformations inside MCPs were random coil. In vitro scratch assay showed that there were significant effects on the scratch closure by the treatment of MCPs with the concentration of 50.0 μg/mL. In the experiments of deep partial-thickness scald wound in rabbits, MCPs could enhance the process of wound healing. Therefore, MCPs from the skin of Nile tilapia ( O. niloticus ) have promising applications in wound care.

Alteration in DNA structure, molecular responses and Na+ -K+ -ATPase activities in the gill of Nile tilapia, Oreochromis niloticus (Linnaeus, 1758) in response to sub-lethal verapamil.

Science.gov (United States)

Ajima, Malachy N O; Pandey, Pramod K; Kumar, Kundan; Poojary, Nalini

2018-01-01

The ecotoxicological consequences of residues from pharmaceutical drugs on aquatic biota have necessitated the development of sensitive and reliable techniques to assess the impact of these xenobiotics on aquatic organisms. This study investigated the alteration in DNA structure, molecular responses and the activities of Na + -K + -ATPase and antioxidant enzymes in the gill of Nile tilapia, Oreochromis niloticus, exposed to long-term effects at the concentrations (0.14, 0.28 and 0.57mgL -1 ) of verapamil in static renewal system for 15, 30, 45 and 60 days. Evaluation of DNA structure, using single cell gel electrophoresis, revealed certain degree of DNA damages in the gill in a time and concentration-dependent relationship. Transcription of mRNA of superoxide dismutase (sod), catalase (cat) and heat shock protein (hsp70) genes in the gill of the fish showed the genes were up-regulated. Na + -K + -ATPase activity was inhibited in a concentration and time dependent manner. The indices of oxidative stress biomarkers (lipid peroxidation and carbonyl protein) as well as superoxide dismutase, glutathione peroxidase, glutathione-S-transferase were elevated in the treated fish in comparison to the control. Further, the level of reduced glutathione and catalase activity were inhibited at 0.28mgL -1 after day 30. Long-term exposure to sub-lethal concentration of verapamil can cause DNA damages, molecular effects and oxidative stress in O. niloticus. The biomarkers analysed can be used as early warning signals in environmental biomonitoring and assessment of drug contamination in aquatic ecosystem. Copyright © 2017 Elsevier Inc. All rights reserved.

Ekstraksi dan Karakterisasi Kolagen dari Kulit Ikan Nila Hitam (Oreochromis niloticus

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A. B. Naro Putra

2013-12-01

Full Text Available Kulit ikan nila hitam (Oreochromis niloticus dapat diekstraksi menjadi kolagen dan turunannya sebagai salah alternatif peningkatan nilai tambah limbah industri perikanan. Ekstraksi kolagen dari sampel kulit ikan nila hitam menggunakan asam asetat (metode asam dan dipresipitasi dengan larutan garam dapur (NaCl 0,9 M. Untuk meningkatkan optimasi isolasi kolagen (berdasarkan jumlah rendemen, kulit ikan nila hitam diekstraksi dengan 3 perlakuan konsentrasi asam asetat, masing-masing: 0,25 M; 0,50 M; dan 0,75 M pada selang waktu 16 dan 48 jam. Dari hasil pengujian diketahui bahwa perlakuan interaksi konsentrasi asam asetat dan waktu ekstraksi tidak berpengaruh nyata (p>0,05 terhadap pembentukan rendemen kolagen pada tingkat signifikansi 95%. Perlakuan asam asetat 0,75 M pada selang waktu 16 jam menghasilkan rendemen terbesar (5,96%, dengan suhu denaturasi kolagen mencapai 35,75 oC; serta komposisi asam amino: glisin 5395,82 ppm (52,99%, alanin 2979,15 ppm (22,08%, dan asam glutamat 1684,42 ppm (7,45%. Berdasarkan analisis SDS-PAGE, diketahui bahwa kolagen dari sampel kulit ikan nila hitam mengandung ikatan rantai- dan rantai- sebagai kolagen tipe-I.

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

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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

Effects of Replacement of Fishmeal with other Alternative Plant Sources in the Feed on Proximate Composition of Muscle, Liver and Ovary in Tilapia (Oreochromis nioloticus

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Khalid Al-Ghanim

2017-08-01

Full Text Available ABSTRACT The major objective of this experiment was to assess the effect of alternate plant protein sources as a replacement for fish meal in feed on the proximate composition of muscle, liver and tissue in Oreochromis niloticus. O. niloticus of average size (average Weight 45.00±1.25 g, total length 13.28±1.42 cm were stocked in 100 L glass aquarium. Fish were fed with three experimental feeds (A, B and C and reference commercial feed (D for 16 weeks. Feed A, B and C was prepared from four different plant sources and fish meal (40 % crude protein. Fish were fed at the rate 3 % of body weight daily. It has been observed that tilapia fed with feed B in which 20 % fish meal was replaced compared to feed C with other plant sources of protein, had shown significantly higher total protein in their muscle compared to diet other experimental and commercial feeds. In O. niloticus minimum lipid content was recorded in fish fed with diet B compared to A, C and commercial feed. It has been concluded that 20-40% level of fish meal can be replaced in the diet of fish without having any impact on growth and chemical composition of muscle.

Comparison of nutritional quality in fish maw product of croaker Protonibea diacanthus and perch Lates niloticus

Science.gov (United States)

Wen, Jing; Zeng, Ling; Chen, Ziming; Xu, Youhou

2016-08-01

Fish maw (the dried swimbladders of fish) is ranked in the list of the four sea treasures in Chinese cuisine. Fish maw is mainly produced from croaker, which is the most highly priced. However, some of the fish maw being sold as croaker maw are in fact not from croaker, but from the Nile perch Lates niloticus. The present work determined and compared the proximate composition, amino acid and fatty acid composition of croaker Protonibea diacanthus maw and perch L. niloticus maw. The results indicated that both maws were high protein sources and low in fat content. The dominant amino acids in both maws were glycine, proline, glutamic acid, alanine and arginine. These amino acids constituted 66.2% and 66.4% of the total amino acids in P. diacanthus and L. niloticus, respectively. The ratio of FAA: TAA (functional amino acids: total amino acids) in both maws were 0.69. This is a good explanation for why fish maws have been widely utilized as a traditional tonic and remedy in Asia. Except valine and histidine, all the essential amino acid contents in P. diacanthus were higher than in L. niloticus. Moreover, croaker P. diacanthus maw contained more AA and DHA than perch L. niloticus maw, showing a higher ratio of n-3 / n-6, which is more desirable.

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

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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 health status. Copyright © 2017 Elsevier Ltd. All rights reserved.

Bacteria Associated with Fresh Tilapia Fish (Oreochromis niloticus ...

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Keywords: Bacteria, Tilapia fish and Sokoto central market. INTRODUCTION ... The bacteria are transmitted by fish that have made contact ... with which a product spoils is also related to the .... Base on the percentage frequency of occurance ,.

Energia digestível para alevinos de tilápia-do-nilo (Oreochromis niloticus Digestible energy for Nile tilapia (Oreochromis niloticus fingerlings

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Wilson Rogério Boscolo

2006-06-01

Full Text Available Avaliou-se o efeito de diferentes níveis de energia digestível na dieta sobre o desempenho de alevinos de tilápia-do-nilo (Oreochromis niloticus. Utilizaram-se 125 alevinos com peso e comprimento iniciais de 0,62±0,12 g e 3,25±0,25 cm, respectivamente, distribuídos em 25 aquários com capacidade de 30 L, em um delineamento experimental inteiramente casualizado, com cinco tratamentos e cinco repetições, em que a unidade experimental consistiu de um aquário contendo cinco alevinos. As rações, isoprotéicas (30% de proteína digestível, isofosfóricas e isocalcíticas, foram formuladas para conter 2.900; 3.025; 3.150; 3.275 e 3.400 kcal/kg de energia digestível. A quantidade de ração fornecida (quatro vezes ao dia correspondeu a 10% da biomassa. Os parâmetros físico-químicos da água (oxigênio dissolvido - OD, pH e condutividade elétrica - CE foram mensurados semanalmente, à tarde, e a temperatura, diariamente, antes da primeira e da última sifonagem, apresentando médias de 8,00±0,05 mg/L; 7,91±0,19; 92,11±2,27 µS/cm e 25,61±0,90ºC, respectivamente. Ao final do experimento, foram analisadas as médias de peso final, ganho de peso, comprimento final, conversão alimentar aparente, sobrevivência e fator de condição. Não foram observadas diferenças no desempenho de alevinos entre os diferentes tratamentos. Recomenda-se a utilização de 2.900 a 3.400 kcal de ED/kg na ração de alevinos de tilápia-do-nilo.The different levels of digestible energy on the performance of Nile tilapia (Oreochromis niloticus fingerlings were evaluated. One hundred and twenty-five fingerlings averaging initial length and weight of 0.62±0.12 and 3.25±0.25 cm were allotted to 25 30L-aquariums, as a completely randomized design with five treatments and five replicates (an aquarium with five fingerlings was considered the experimental unit. The diets, formulated to be isonitrogenous (30% of digestible protein, isophosphorous and isocalcium

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

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Effendi, Hefni; Wahyuningsih, Sri; Wardiatno, Yusli

2017-10-01

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.

Substituição do milho pela silagem de sorgo com alto e baixo teor de tanino em dietas para juvenis de tilápia do Nilo (Oreochromis niloticus - DOI: 10.4025/actascianimsci.v25i2.1989 Replacement of corn by sorghum silage with low and high tannin contents in diets for juvenile Nile tilapia (Oreochromis niloticus- DOI: 10.4025/actascianimsci.v25i2.1989

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Patrícia Ribeiro Neves

2003-04-01

Full Text Available Este trabalho foi realizado para avaliar a substituição do milho pela silagem de sorgo como fonte de energia para juvenis de tilápia do Nilo, Oreochromis niloticus L. (Cichlidae. Foram formuladas 3 dietas práticas isocalóricas (3000kcal de energia digestível e isoprotéica (28% de proteína bruta. O farelo de milho foi substituído pela silagem de sorgo de baixo (0,44% (SSBT e alto (1,14% (SSAT teor de tanino. Os peixes (55,09 ± 0,94g foram distribuídos em tanques de fibro-cimento (1000L e alimentados com dietas experimentais até à saciedade 3 vezes ao dia, durante 67 dias. Não foram observadas diferenças significativas sobre a conversão alimentar, eficiência protéica, índice hepato-somático, gordura visceral e taxa de sobrevivência. O ganho de peso dos peixes alimentados com SSBT foi significativamente maior que os alimentados com dietas contendo milho e SSAT. Os peixes alimentados com dietas contendo SSBT consumiram mais ração do que os peixes alimentados com a dieta com SSAT. Os resultados indicaram que a inclusão de 44% de silagem de sorgo nas dietas podem suportar normal crescimento nos juvenis de tilápia do Nilo, com potencial para substituir o milho.This work was carried out to evaluate the replacement of corn by sorghum silage as an energy source for juvenile Nile tilapia, Oreochromis niloticus L. (Cichlidae. Three isocaloric (3000kcal of digestible energy and isoproteic (28% of crude protein practical diets were formulated. Corn meal was totally substituted by low (0.44% (LTSS and high (1.14% (HTSS tannin contents silage sorghum. Fish (55.09 ± 0.94g were reared in fiberglass tanks (1000L and hand-fed with experimental diets until reach they satiation, three times a day during 67 days. Feed conversion, protein efficiency ratio, hepatosomatic index, visceral fat and survival ratio of fish fed with the diets were not significantly different. Weight gain of fish fed with LTSS diet was significantly higher than those

Efeito da lavagem e da adição de aditivos sobre a estabilidade de carne mecanicamente separada de tilápia do Nilo (Oreochromis niloticus durante estocagem a -18 ºC Effect of washing and increase of additives on minced stability of Nile tilapia (Oreochromis niloticus during storage under -18 ºC

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Peter Gaberz Kirschnik

2009-03-01

Full Text Available Este estudo teve como objetivo avaliar a influência da lavagem e da adição de eritorbato de sódio e tripolifosfato de sódio na estabilidade de Carne Mecanicamente Separada (CMS de tilápia de Nilo (Oreochromis niloticus durante 6 meses de armazenamento a -18 ºC. A CMS obtida por meio de máquina separadora de carne e ossos foi dividida em quatro tratamentos (CMS lavada com e sem aditivos, e CMS não lavada com e sem aditivos e mantida sob congelamento a -18 ºC, por 180 dias. A estabilidade foi avaliada por meio de análises microbiológicas e determinações de nitrogênio não proteico (NNP, bases nitrogenadas voláteis (BNV, substâncias reativas ao ácido tiobarbitúrico (TBARS, pH e drip (perda de água no descongelamento. O processo de lavagem causou redução de aproximadamente 41, 44 e 66% nos teores de proteína bruta, lipídios e cinzas, respectivamente, reduzindo também os valores iniciais de NNP, BNV e TBARS. Durante o armazenamento, foram observados aumentos (p 0,05 os teores de TBARS. Os parâmetros microbiológicos avaliados não ultrapassaram os limites permitidos pela legislação. As CMS permaneceram estáveis e em boas condições de utilização, independentemente da inclusão de aditivo, sendo viável sua estocagem a -18 ºC por 180 dias.This study evaluates the influence of washing and adding sodium erythorbate and sodium tripolyphosphate on the stability of minced Nile Tilapia (Oreochromis niloticus during 6 months of storage under -18 ºC. The minced fish was obtained using a meat bone separator and was divided into four treatments (washed minced fish with or without additives and non-washed minced fish with or without additives and kept at -18 ºC for 180 days. The stability of the minced fish was evaluated by microbiological analyses and the following parameters non-proteic nitrogen (NNP, total nitrogen volatile bases (BNV, Thiobarbituric Acid Reactive Substances (TBARS, pH, and Drip (loss of water in thaw

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

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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.

[Centrocestus formosanus (Opisthorchiida: Heterophyidae) as a cause of death in gray tilapia fry Oreochromis niloticus (Perciforme: Cichlidae) in the dry Pacific of Costa Rica].

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Arguedas Cortés, Donald; Dolz, Gaby; Romero Zúñiga, Juan J; Jiménez Rocha, Ana E; León Alán, Dennis

2010-12-01

Centrocestusformosanus is a zoonotic trematode from Asia and has been mainly associated as cause of death of cultured fish. To identify pathogen trematode species in tilapia fry (Oreochromis niloticus) and to determine mollusks hosting these parasites, freshwater mollusks were collected from tilapia cultured ponds and experimental infections were carried out with tilapia fries and different mollusk species. A total of 907 freshwater mollusks were obtained from tilapia ponds and were identified to species level, four gastropods and one bivalve were determined: Melania tuberculata, Melanoides turricula, Pomacea flagellata, Haitia cubensis and Anodontiles luteola. For the first time, the presence of M. turricula and H. cubensis are reported in Costa Rica. Seven morphotypes of cercariae (Xifiodiocercaria, Equinostoma, Oftalmocercaria, Parapleurolofocercus, Cistocerca, Furcocercaria and Leptocercaria) parasitizing all five species of mollusks were found, all of distome type. Experimental exposure of tilapia fry to M. tuberculata demonstrated that the parapleurolofocercus morphotype found in the mollusk is in accordance with the finding of C. formosanus in tilapia fry. An abundance and mean intensity of 1018-1027 digeneans per gill in each exposed fish was determined. Centrocestus formosanus is reported for the first time in Costa Rica, for which the primary and secondary intermediate hosts were also determined.

Nutritional Profile and Chemical Stability of Pasta Fortified with Tilapia (Oreochromis niloticus) Flour.

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Monteiro, Maria Lúcia G; Mársico, Eliane T; Soares, Manoel S; Magalhães, Amanda O; Canto, Anna Carolina V C S; Costa-Lima, Bruno R C; Alvares, Thiago S; Conte, Carlos A

2016-01-01

Physicochemical parameters of pasta enriched with tilapia (Oreochromis niloticus) flour were investigated. Five formulations were prepared with different concentrations of tilapia flour as partial substitute of wheat flour: pasta without tilapia flour (PTF0%), pasta with 6% (PTF6%), 12% (PTF12%), 17% (PTF17%), and 23% (PTF23%) of tilapia flour. The formulations were assessed for proximate composition, fatty acid and amino acid profile on day 1 whereas, instrumental color parameters (L*, a* and b* values), pH, water activity (aw), and lipid and protein oxidation were evaluated on days 1, 7, 14, and 21 of storage at 25°C. Fortification with tilapia flour increased (p pasta with tilapia flour decreased (p pasta containing 12%, 17%, and 23% of tilapia flour than their counterparts, and the storage promoted an increase (p pasta with 6% of tilapia flour has the potential to be a technological alternative to food industry for the nutritional enrichment of traditional pasta with negligible negative effects on the chemical stability of the final product during 21 days at 25°C.

Meningoencephalitis in farmed monosex Nile tilapia (Oreochromis niloticus L. caused by Streptococcus agalactiae

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Adikesavalu Harresh

2017-09-01

Full Text Available Aquaculture of tilapia is a new research venture in India. With intensification in farming practices, tilapia are increasingly susceptible to bacterial infections. This article describes the isolation and identification of pathogenic bacteria from cultured monosex Nile tilapia, Oreochromis niloticus (L., that experienced moderate to severe mortalities in West Bengal, India between September and August 2014 and histopathological alterations in various organs. Gram-positive diplococci, identified as Streptococcus agalactiae with Streptococcus identification kits and 16S rDNA sequencing analysis, were isolated from the brain, operculum, and kidney. Other bacteria from the kidney were identified as Aeromonas sobria, A. caviae, Klebsiella pneumoniae ssp. pneumoniae, Escherichia coli, and Enterobacter cloacae. Staphylococcus epidermis was isolated from opercular hemorrhages. Histological sections of the infected tilapia brain revealed meningoencephalitis and granulomatous lesions. Sections from other organs indicated congestion, hemorrhagic and hyperplastic cells, necrosis, vacuolation, hemosiderin deposition, hypertrophic nuclei, melanomacrophage aggregation, and ruptured veins. This report is the first description of S. agalactiae as a primary pathogen causing meningoencephalitis in cultured tilapia in India.

Capability of some agricultural wastes for removing some heavy metals from polluted water stocked in combination with Nile tilapia, Oreochromis niloticus (L.

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Mohsen Abdel-Tawwab

2017-04-01

Full Text Available Abstract Heavy metal (HM pollution is one of the major problems that adversely affect the aquatic ecosystem and inhabiting biota. Heavy metals adsorption by low-cost adsorbents is one of the techniques used for HM removing from polluted water. In the present study, agricultural wastes (AW, i.e., rice straw, sugarcane bagasse, and maize stalks, were washed with distilled water, dried in a dry-oven, cut into small pieces (<0.5 cm long, and immersed at 1.0 g/L in aquaria containing synthetic mixture of lead (Pb, cadmium (Cd, copper (Cu, and zinc (Zn. Nile tilapia, Oreochromis niloticus (L., fingerlings (25.2 ± 0.88 g were stocked at a density of ten fish per 100-L aquarium for 72 h, during which fish were fed on a fish diet containing 25% crude protein ad libitum twice daily. Samples of water, AW, and fish were collected at different times to determine HM concentrations. The HM removal from polluted water was depending on the type of the metal ions, AW, and the contact time. However, HM concentrations in aquaria waters of all AW treatments decreased significantly by increasing contact time up to 24 h after which their concentrations were almost the same. Concentrations of waterborne Pb, Cd, Cu, and Zn in AW-containing aquaria were significantly lower than those of AW-free aquaria. The presence of any AW reduced significantly HM concentrations. In AW-free aquaria, HM-exposed fish accumulated more HM in their body than those reared in AW-containing aquaria. The results of this experiment showed that all AW had the capability to remove HM levels from the polluted water and reduce their bioaccumulation in fish body. However, rice straw was the more efficient adsorbent for all metals.

Effects of sub-chronic exposure to zinc nanoparticles on tissue accumulation, serum biochemistry and histopathological changes in tilapia (Oreochromis niloticus)

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Kaya, Hasan; Duysak, Müge; Akbulut, Mehmet; Yılmaz, Sevdan; Gürkan, Mert; Arslan, Zikri; Demir, Veysel; Ateş, Mehmet

2016-01-01

Zinc nanoparticles (ZnNPs) are among the least investigated NPs and thus their toxicological effects are not known. In this study, tilapia (Oreochromis niloticus) were exposed to 1 and 10 mg/L suspensions of small size (SS, 40–60 nm) and large size (LS, 80–100 nm) ZnNPs for 14 days under semi-static conditions. Total Zn levels in the intestine, liver, kidney, gill, muscle tissue and brain were measured. Blood serum glucose (GLU), glutamic oxaloacetic transaminase (GOT), glutamic pyruvic transaminase (GPT), and lactate dehydrogenase (LDH) were examined to elucidate the physiological disturbances induced by ZnNPs. Organ pathologies were examined for the gills, liver and kidney to identify injuries associated with exposure. Significant accumulation was observed in the order of intestine, liver, kidney and gills. Zn levels exhibited time- and concentration-dependent increase in the organs. Accumulation in kidney was also dependent on particle size; NPs SS-ZnNPs were trapped more effectively than LS-ZnNPs. No significant accumulation occurred in the brain (p>0.05) while Zn levels in muscle tissue increased only marginally (p≥0.05). Significant disturbances were noted in serum GOT and LDH (p0.05). Histopathological tubular deformations and mononuclear cell infiltrations were observed in kidney sections. In addition, an increase in melano-macrophage aggregation intensity was identified on the 7th day in treatments exposed to LS-ZnNPs. Mononuclear cell infiltrations were identified in liver sections for all treatments. Both ZnNPs caused basal hyperplasia in gill sections. Fusions appeared in the gills after the 7th day in fish treated with 10 mg/L suspensions of SS-ZnNPs. In addition, separations in the secondary lamella epithelia were observed. The results indicated that exposure to ZnNPs could lead to disturbances in blood biochemistry and cause histopathological injuries in the tissues of O. niloticus. PMID:27464841

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.

Determination of selenium toxicity to Oreochromis niloticus based on hematological parameters - doi: 10.4025/actascibiolsci.v34i2.8755

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Julio Vicente Lombardi

2012-03-01

Full Text Available Selenium (Se is described as an essential micronutrient and participates in different biological functions, as the antioxidant defense systems maintenance and regulation. However, when in high concentrations, Se may cause toxic effects as well as hematological changes in fish. The aim of the present study was to determine the toxicity of selenium in the form of sodium selenate (Na2Se6+O4 in Oreochromis niloticus based on hematological parameters, after exposure to different concentrations (0.01, 0.14 and 1.4 mg Se6+ L-1. The erythrocytic and leukocytic series were examined over 14 days at intervals of 0, 3, 5, 7,10 and 14 days. The erythrocytic series showed significant alterations in the first 7 days, including the control group. Neutrophils and monocytes showed variations in the first 3 days at a concentration of 1.40 mgSe6+ L-1 characterizing an acute response. The total number of leukocytes was different in relation to time zero on all Se concentrations. The thrombocyte count also differed statistically from time zero and control in the first 3 days at 0.14 mgSe6+ L-1. These results indicate that different concentrations induce an acute response with diminution of total leukocytes, neutrophilia, monocytosis and thrombocytosis. 

RAPD-SCAR Markers for Genetically Improved NEW GIFT Nile Tilapia (Oreochromis niloticus niloticus L.) and Their Application in Strain Identification.

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Li, Si-Fa; Tang, Shou-Jie; Cai, Wan-Qi

2010-04-01

The NEW GIFT Nile tilapia (Oreochromis niloticus niloticus L.) is a nationally certificated new strain selected over 14 years and 9 generations from the base strain of GIFT Nile tilapia, introduced in 1994. This new variety has been extended in most of areas of China. The management of genetically improved strains, including the genetic markers for identification is needed urgently. RAPD analysis was conducted and their conversion to SCAR markers was developed. From NEW GIFT Nile tilapia, two strain-specific RAPD bands, S(304 )(624 bp ) and S(36 )(568 bp ) were identified. The strain-specific RAPD bands were gel-purified, cloned, and sequenced. Locus-specific primers were then designed to amplify the strain-specific bands. PCR amplification was conducted to test the variations in allele frequencies of two converted SCAR markers among the NEW GIFT Nile tilapia and its base strains, as well as 7 additional farmed strains worldwide. The frequency of SCAR marker I (553 bp) was 85.7% in NEW GIFT Nile tilapia, but 16.7% in the base strain. The frequency of SCAR marker II (558 bp) was 91.4% in NEW GIFT Nile tilapia, but 0% - 70% in the 7 other strains. In order to confirm the utility of these two markers, an examination was conducted for a wild population from Egypt, resulted the frequency of SCAR I and II was 10% and 70%, respectively, much lower than that of New GIFT strain. The increase in allele frequency of these two SCAR markers suggests that these markers might be genetically linked to the quantitative trait loci (QTL) underlining the performance traits by long term selection, and indicate the bright potential of SCAR marker technology for tracking generations during selection progress and for distinguishing among genetically improved strain and other strains.

KUALITAS PAKAN FERMENTATIF BERBAHAN KULIT UBI KAYU DENGAN INOKULAN MEP+ UNTUK KULTUR IKAN NILA GESIT (Oreochromis niloticus L.

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Cahiadir Ali Akbar

2014-06-01

Full Text Available Feed is a major component in fish farming. However, the relatively high price of feed is very burdensome for fish farmers. Therefore a relatively low-cost solution is needed to address that problem. The use of local materials such as bran, waste mushroom, tofu, onggok starch, and skin cassava can be utilized as an alternative to reduce the needs of imported materials. However, the local materials have constraints regarding nutrition and digestibility, so an appropriate technology is required to overcome this. Improving the quality of the feed can be done by fermentation. Fermentation works by breaking macromolecules such as carbohydrates and amino acids into micromolecules, so the absorption of feed nutrients in the fish intestines become more efficient. The use of inoculants MEP+ aimed to improve the digestibility of feed, detoxification and increased the productivity of tilapia GESIT (Oreochromis niloticus. This study aimed to determine the effect of fermentation on enhancing the quality of feed nutrients made from cassava skin chips by the application of inoculant MEP+. The study was carried out experimentally using a complete randomized design. The independent variable in this study was the type of feed. Observed dependent variable was feed quality. The main parameter measured was the proximate level. Supporting parameter was the growth of tilapia GESIT. The results showed a progressive increase in the levels of nutrients of feed fermented in each treatment. The increments were recorded in treatment A from 16.15 became 21.64, in B from 13.21 became 15.46, in C from 9.66 became 11.53, and in D from 8.34 became 9.87. This result implies that the use of MEP+ fermentation inoculants could boost the nutritional content of food, with an average of the increment value of 11-15%. The increment of nutrient contents in each treatment was also affected the weight gain of fish although no significant difference were observed.

Sex-specific differences in the synaptonemal complex in the genus Oreochromis (Cichlidae).

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Campos-Ramos, Rafael; Harvey, Simon C; Penman, David J

2009-04-01

Total synaptonemal complex (SC) lengths were estimated from Oreochromis aureus Steindachner (which has a WZ/ZZ sex determination system), O. mossambicus Peters and O. niloticus L. (both of which have XX/XY sex determination systems). The total SC length in oocytes was greater than that in spermatocytes in all three species (194 +/- 30 microm and 134 +/- 13 microm, 187 +/- 22 microm and 127 +/- 17 microm, 193 +/- 37 microm and 144 +/- 19 microm, respectively). These sex-specific differences did not appear to be influenced by the type of sex determination system (the female/male total SC length ratio was 1.45 in O. aureus, 1.47 in O. mossambicus and 1.34 in O. niloticus) and do not correlate with the lack of any overall sex-specific length differences in the current Oreochromis linkage map. Although based on data from relatively few species, there appears to be no consistent relationship between sex-specific SC lengths and linkage map lengths in fish. Neomale (hormonally masculinized genetic female) O. aureus and O. mossambicus had total SC lengths of 138 +/- 13 microm and 146 +/- 13 microm respectively, more similar to normal males than to normal females. These findings agree with data from other vertebrate species that suggest that phenotypic sex, rather than genotype, determines traits such as total SC length, chiasmata position and recombination pattern, at least for the autosomes.

Histologic structure of red nile tilapia fish (Oreochromis nilloticus Var.) gill which is exposed to lead acetate

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Utami, N. R.; Widiyaningrum, P.; Iswari, R. S.

2018-03-01

Fish is a water biota commonly used as the bioindicator of water pollution level. One of the animals which are recommended by EPA as the test species is red Nile Tilapia fish (Oreochromis niloticus var). The purpose of this research is to get the value of LC50-96 hours in the toxicity test toward the fishes which are exposed to lead acetate with some details identification of the gills damage by gill histologic structure examination together with the determination of the lead concentration which caused the destruction. Sixty fish were used in the preliminary test to detect the threshold concentration (LC0-48 h); whereas 120 fish were used in the toxicity test to get the mortality level of fish up to 50% in 96 h. Finally, for treatment test, there were 80 fish which were exposed to lead acetate in the concentration of 0 ppm, 259.51 ppm, 291.94 ppm and 324.38 ppm. All the treatment tests were given for four weeks. The data were collected at the end of the 4th week, and then, the description of the fish gill histology structure was done. The histology observation of the fishes gill detected some damages in the form of edema (0% -25%), lamellar fusion (1% -75%), hyperplasia (0% -50%), epithelial lifting (0% -50%), and necrosis (0% -50%). The results indicate that administration of lead acetate accelerates moderate damage to the red Nile tilapia fish gill structure. The greatest level of damage is lamellar fusion, while the other decline damages are edema, hyperplasia, epithelial lifting, and necrosis. Furthermore, it can be concluded that LC50-96 hours value in the lead acetate toxicity test of red Nile tilapia fish is 324,38 ppm with some histologic structure damage in the gill the fishes.

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

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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. Copyright © 2016 Elsevier Ltd. All rights reserved.

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.

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

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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.

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.; Alam, Aftab

2013-01-01

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.

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.

Isolation of Streptococcus spp from nile tilapia (Oreochromis niloticus and quality of water in hapas nets in North Region of Parana State, Brazil/ Isolamento de Streptococcus spp de tilápias do nilo (Oreochromis niloticus e qualidade da água de tanques rede na Região Norte do Estado do Paraná, Brasil

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Aleksey Machado Moreno

2003-05-01

Full Text Available This study evaluated 12 intensive breed of Nile tilapia (Oreochromis niloticus in four properties localized in the north of Parana State, Brazil. In the period of 13 months, 71 fishes were collected and analyzed of hapas nets that presenting morbidity and mortality of tilapias. Parallel, to evaluate the quality of the water of these hapas nets, there was measured the temperature, dissolved oxygen, pH, alkalinity, nitrite and ammonia. Of the 71 fishes, were collected 220 biological samples. 17 (23.94% fishes were positive for Streptococcus spp. Of the 53 biological samples from 17 fishes, in 24 (45.28% were isolated streptococci. The main clinical signs and macroscopic lesions in the fishes with isolation of Streptococcus spp. were hepatomegaly and splenomegaly, skin lesion and base of the fins and exoftalmia with cornea opacity. The higher incidence of infections caused by streptococci happened in the months with higher temperatures, mainly in the transition period winter for spring. The values of dissolved oxygen, pH, alkalinity, nitrite and ammonia of the water were normal.Foram estudados doze tanques-rede de quatro propriedades de criação intensiva de tilápia do Nilo (Oreochomis niloticus da região Norte do Paraná, Brasil. No período de 13 meses foram analisados 71 peixes provenientes de tanques apresentando morbidade e mortalidade de tilápias. Paralelamente, para avaliar a qualidade da água destes tanques, foi medida a temperatura, oxigênio dissolvido, pH, alcalinidade, nitrito e amônia. Dos 71 peixes, foram coletadas 220 materiais biológicos. Em 17 (23.94% peixes foram isolados Streptococcus spp e dos 53 materiais biológicos provenientes destes peixes, 24 (45.28% apresentaram Streptococcus spp. Os principais sinais clínicos e lesões macroscópicas nos peixes com isolamento de Streptococcus spp foram hepatomegalia e esplenomegalia, lesão de pele e base das nadadeiras e exoftalmia com opacidade de córnea. O maior número de

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.

Fatty Acid Composition and Levels of Selected Polyunsaturated Fatty Acids in Four Commercial Important Freshwater Fish Species from Lake Victoria, Tanzania

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Agnes Robert

2014-01-01

Full Text Available Fatty acids (FAs particularly ω3 and ω6 polyunsaturated fatty acids (PUFAs play important role in human health. This study aimed to investigate the composition and levels of selected ω3 PUFAs in four commercial fish species, Nile perch (Lates niloticus, Nile tilapia (Oreochromis niloticus, Tilapia zillii, and dagaa (Rastrineobola argentea from Mwanza Gulf in Lake Victoria. The results indicated that 36 types of FAs with different saturation levels were detected. These FAs were dominated by docosahexaenoic (DHA, eicosapentaenoic (EPA, docosapentaenoic (DPA, and eicosatetraenoic acids. O. niloticus had the highest composition of FAs (34 compared to L. niloticus (27, T. zillii (26, and R. argentea (21. The levels of EPA differed significantly among the four commercial fish species (F=6.19,  P=0.001. The highest EPA levels were found in R. argentea followed by L. niloticus and O. niloticus and the lowest in T. zillii. The DPA levels showed no significant difference among the four fish species studied (F=0.652,  P=0.583. The study concluded that all four commercial species collected from Mwanza Gulf are good for human health, but R. argentea is the best for consumption because it contains higher levels of ω3 FAs, mainly EPA.

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

DESEMPEÑO PRODUCTIVO, COMPOSICIÓN Y BIODISPONIBILIDAD RELATIVA DE SELENIO EN TILAPIA NILÓTICA -Oreochromis niloticus- SUPLEMENTADA CON SELENIO ORGÁNICO E INORGÁNICO

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J. E. Vinchira; G. A. Wills; A. P. Muñoz

2014-01-01

Se evaluó el desempeño productivo, la composición corporal y la biodisponibilidad relativa de selenio en tilapia nilótica ( Oreochromis niloticus ) suplementada con selenio dietario. Una dieta basal fue suplementada con selenio en forma de selenito de sodio o seleno-levadura en niveles crecientes de suplementación (0.00, 0.10, 0.20, 0.40, 0.80 y 1.60 mg/kg de dieta). Un total de 336 individuos de tilapia nilótica, con un peso inicial de 13.41±0.12 g, fueron distribuidos de forma aleatori...

Resistência a antimicrobianos de bactérias oriundas de ambiente de criação e filés de tilápias do nilo (Oreochromis niloticus Antibacterial resistance in bacteria from fish pond and Nile tilapia fillets (Oreochromis niloticus

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Rejeana Márcia Santos Lima

2006-02-01

Full Text Available A resistência de bactérias a antimicrobianos foi determinada em uma piscicultura de tilápias (Oreochromis niloticus em tanques de terra, sem utilização de antibióticos para profilaxia ou controle de doenças. Foi selecionado um tanque, capturados peixes e coletadas amostras de conteúdo intestinal e superfície dos peixes, água de abastecimento e do tanque, ração, filés de tilápias frescos e congelados. Colônias representativas foram selecionadas e analisadas pelos testes de Gram, catalase, oxidase e oxidaçãofermentação. Foram selecionadas 89 amostras e submetidas a antibiograma, utilizando vários antimicrobianos. A maioria das bactérias pertenceu às famílias Enterobacteriaceae e Vibrionaceae. Tanto no ambiente de criação como nos filés de tilápias observou-se que os isolados bacterianos apresentaramse resistentes principalmente a ampicilina e eritromicina. O índice de múltipla resistência a antimicrobianos (MAR foi calculado, sendo que do total de 89 isolados analisados 74 (83%, apresentaram MAR ³ 0,2, ou seja apresentaram-se resistentes a dois ou mais antimicrobianos. As freqüências de índice MAR foram altas e maiores na ração.This study was conducted in a freshwater tilapia farm that has not used any antibiotic. It was selected one pond, caught 15 fishes and collected samples of intestinal content and mucus surface, water influent and pond water, ration, fresh tilapia fillets and frozen fillets.. Phenotypical characteristics, Gram stain, oxidase production, oxidative-fermentative utilization of glucose (O-F were determined of representative colony. Were selected 89 strains and submitted for antimicrobial sensitivy test using several antibiotics. The major identified bacterial families were belonged Enterobacteriaceae and Vibrionaceae. The most isolates showed resistance to ampicilin and eritromicin. From the 89 isolates evaluated 74 (83% showed a multiple antibiotic resistance index (MAR ³ 0.2, that mean

Contribution to the Identification of a Local and Available Food Source for Sustainable Production of Nile Tilapia (Oreochromis niloticus, Linnaeus, 1758 in the Democratic Republic of Congo

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Tshinyama, A.

2018-01-01

Full Text Available This experiment was conducted in parallel with work in the Democratic Republic of the Congo with the objective to evaluate the growth performance and production costs of Nile tilapia fed diets formulated using local plant protein sources, and to compare them to those obtained with an optimized commercial fish feed. Ninety monosex male tilapia juveniles (Oreochromis niloticus; mean weight 17.3 ± 0.2 g; mean length 9.6 ± 0.1 cm were reared in 9 acrylic aquaria supplied by closed water recirculation system. Three diets were tested in triplicate: 1 Rcongo, the test diet formulated by using local feed ingredients collected in the DR-Congo; 2 Rcanada, the diet formulated with the same ingredient composition as the first one, but sourced in Canada; and 3 Rcommercial, a fishmeal-based commercial control diet. In vivo feed digestibility and biochemical analysis of samples were carried out. The effects of diet and rearing time were measured on fish performance, including fish biomass, K coefficient, weight gain (WG, feed efficiency (FE, feed conversion rate (FCR, specific growth rate (SGR, protein efficiency ratio (PER, apparent digestibility coefficient (ADC and on nutrient budget and fish biochemical composition. After four weeks, the fish achieved weight gains of 52% for Rcongo diet (17.2 ± 0.4 to 26.2 ± 2.6 g, 59% for Rcanada diet (17.4 ± 0.1 to 27.6 ± 3.2 g and 153% for the commercial diet (17.3 ± 0.2 to 43.8 ± 2.0 g. The cost-benefit analysis has indicated that the Rcongo diet was economically advantageous, reducing fish production cost up to 36% compared to commercial feed.

Growth, immune responses and protection of Nile tilapia Oreochromis niloticus immunized with formalin-killed Streptococcus agalactiae serotype Ia and III vaccines

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Atchariya Suwannasang

2017-08-01

Full Text Available The protective efficacy of formalin-killed Streptococcus agalactiae (Group B Streptococcus, GBS serotype Ia (GBS-Ia and III (GBS-III vaccines were assessed in Nile tilapia (Oreochromis niloticus. The fish with an average weight of 34.45± 0.08 g were immunized by intraperitoneal (i.p. injection with 4 different formalin-killed vaccines prepared from GBS-Ia (1x1010 CFU/mL, GBS-III (1x1010 CFU/mL, and combined GBS-Ia and GBS-III in an equal volume at final concentrations 1x1010 CFU/mL and 2x1010 CFU/mL in comparison with the non-immunized control group. At 2 and 4 weeks post vaccination, no significant differences were observed (p>0.05 among treatments in growth performance or haemato-immunological parameters, except the increased red blood cell at 2 weeks. Significantly increased antibody titers (p<0.05 against GBS-Ia and GBS-III antigens were noted in the groups immunized with homologous GBS vaccines, whereas the group reacted with heterologous GBS antigen showed less antibody titer as compared with the control group. The vaccination experiment indicated that i.p. injection of Nile tilapia with formalin-killed cells prepared from GBS-Ia or GBS-III provides significant protection, with relative percent survival (RPS value of 52.17 to 71.42%, against a challenge with the homologous serotype isolate, whereas the RPS in fish challenged with a heterologous serotype isolate varied from 20.00 to 53.57%. These results suggested that vaccines from either GBS-Ia or GBS-III have insufficient cross-protective efficacy against the other serotypes. However, a mixed vaccine produced from both GBS serotypes Ia and III provided significant protection with 65.00 to 95.66% RPS which could be an excellent vaccine to protect fish against streptococcosis caused by both GBS serotypes Ia and III.

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

Distinct expression of three estrogen receptors in response to bisphenol A and nonylphenol in male Nile tilapias (Oreochromis niloticus).

Science.gov (United States)

Huang, Weiren; Zhang, Yong; Jia, Xiaoping; Ma, Xilan; Li, Shuisheng; Liu, Yun; Zhu, Pei; Lu, Danqi; Zhao, Huihong; Luo, Wenna; Yi, Shibai; Liu, Xiaochun; Lin, Haoran

2010-06-01

Environmental estrogens, such as bisphenol A (BisA) and nonylphenol (NP), have been shown to affect the estrogen receptor (ER) expression and induce male reproductive abnormalities. To elucidate molecular mechanisms of action of xenoestrogenic chemicals on the expression of estrogen receptors in the testes of Nile tilapia (Oreochromis niloticus), three full-length cDNAs respectively encoding ntERalpha, ntERbeta1 and ntERbeta2 were cloned from testes. The amino acid sequences of ntERalpha, ntERbeta1 and ntERbeta2 showed a high degree of similarity to the relevant fish species. Tissue-specific expression study showed that three receptors were highly expressed in pituitary, liver, testis, kidney and intestine tissues. The ntERalpha, ntERbeta1 and ntERbeta2 mRNA expressions were significantly higher at the sexual early recrudescing stage than at other recrudesced stages. After being exposed to xenoestrogens from weeks 2 to 4, the ntERalpha mRNA levels were increased significantly in testes after NP treatment at all sampling times or after 4 weeks of exposure to BPA. The ntERbeta1 mRNA levels remained unchanged, while a significant decrease of the ntERbeta2 mRNA level was observed in testes after exposure to NP and BPA. The present study demonstrates that the regulation of all three ntER subtypes in testes may act via different molecular mechanisms of exposure to NP and BPA.

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

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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.

Modulatory role of dietary Chlorella vulgaris powder against arsenic-induced immunotoxicity and oxidative stress in Nile tilapia (Oreochromis niloticus).

Science.gov (United States)

Zahran, Eman; Risha, Engy

2014-12-01

Arsenic intoxicant have long been regarded as an impending carcinogenic, genotoxic, and immunotoxic heavy metal to human and animals as well. In this respect, we evaluated biomarkers of the innate immune response and oxidative stress metabolism in gills and liver of Nile tilapia (Oreochromis niloticus) after arsenic exposure, and the protective role of Chlorella vulgaris (Ch) dietary supplementation were elucidated. Protective role of C. vulgaris (Ch), as supplementary feeds (5% and 10% of the diet) was studied in Nile tilapia (O. niloticus) against arsenic induced toxicity (NaAsO2 at 7 ppm) for 21 days exposure period. A significant down-regulation in innate immune response; including, respiratory burst, lysozyme, and bactericidal activity followed due to deliberately As(+3) exposure. Similarly, oxidative stress response; like nitric oxide (NO), catalase (CAT), glutathione (GSH), glutathione peroxidase (GPx), malondialdehyde (MDA) and hydrogen peroxide (H2O2) levels were significantly decreased. Combined treatment of Ch and As(+3) significantly enhanced the innate immune response and antioxidant activity. Strikingly, Ch supplementation at 10% has been considered the optimum for Nile tilapia since it exhibited enhancement of innate immune response and antioxidant activity over the level 5%, and even better than that of control level. Thus, our results concluded that dietary Ch supplementation could protect Nile tilapia against arsenic induced immunosuppression and oxidative stresses. Copyright © 2014 Elsevier Ltd. All rights reserved.

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

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.

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

High vitamin A content in some small indigenous fish species in Bangladesh: perspectives for food-based strategies to reduce vitamin A deficiency

DEFF Research Database (Denmark)

Roos, N.; Leth, Torben; Jakobsen, Jette

2002-01-01

Recognising the importance of fish in the Bangladeshi diet, the objective of the present study was to screen commonly consumed fish species for vitamin A content to evaluate the potential of fish as a vitamin A source in food-based strategies to combat vitamin A deficiency. Samples of 26 commonly...... (Colisa lalia; an alternative scientific name is Colisa lalius). The vitamin A content in cultured species, silver carp (Hypophthalmichthys molitrix), rui (Labeo rohita), mrigal (Cirrhinus mrigala) and tilapia (Oreochromis niloticus) was low,...

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

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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.

Effect of dietary probiotic dose and duration on immune and oxidative stress parameters in juvenile tilapia (Oreochromis niloticus

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Maria Amélia Ramos

2014-06-01

Full Text Available Probiotics, “living organisms, which when administered in adequate amounts confer a health benefit to the host”, can contribute to a more sustainable aquaculture. Their administration through the diet or raising water can modulate the host immune status, improving their resistance towards infection. The antioxidant defence system of the organism is strongly related to immune system and previous studies reported enhancement in antioxidant status of shrimps and fish after probiotic administration, contributing to enhanced resistance towards infections. Nevertheless the information on oxidative stress parameters after probiotic administration in fish is still limited. The present work evaluates the effects of dietary probiotics supplementation on innate immune and oxidative stress parameters in juvenile Nile tilapia (Oreochromis niloticus. A standard diet (27.5% CP, 8.2% CL, 19.6MJ.kg-1 DM was supplemented with a commercial multi-species probiotic (Bacillus sp., Pedicoccus sp., Enterococcus sp., Lactobacillus sp. at two concentrations: A1 (3 g.kg-1; 9 × 105 CFU.g-1 and A2 (6 g.kg-1; 2 × 106 CFU.g-1 and tested against an unsupplemented diet (A0. Fish (12.8 g were hand-fed the experimental diets (3 tanks/treatment; 20 animals per tank, 3 times a day, until visual satiation for 8 weeks. Animals were reared at 24ºC in a closed recirculating freshwater system. During the experiment, at 2, 4 and 8 weeks, blood, head-kidney and liver were sampled to study the following immunological and oxidative stress parameters: plasma lysozyme and alternative complement pathway activity (expressed as ACH50, respiratory burst activity and nitric oxide production of head-kidney leucocytes and liver lipid peroxidation (LPO, catalase (CAT, total glutathione (TG, glutathione peroxidase (GPX, and glutathione reductase (GR activities. Respiratory burst activity and nitric oxide production in head-kidney leucocytes were not significantly affected by probiotic treatment

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.

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

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 < 0.05); the highest innate immune responses were observed in fish fed combinational diet (kefir + LMWSA) (P < 0.05). The results of experimental challenge revealed significantly higher resistance against Streptococcus agalactiae in fish fed supplemented diets and the highest post challenge survival rate was observed in synbiotic diet (P < 0.05). Similar results obtained in case of growth parameters. Feeding on supplemented diet significantly improved SGR and FCR and the highest growth parameters was observed in fish fed synbiotic diet (P < 0.05). These finding revealed that combined administration of dietary 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.

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

Toxicidade aguda e risco ambiental do antibiótico oxitetraciclina para tilápia ( Oreochromis niloticus , Daphnia magna e Lemna minor

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A.A. Machado

Full Text Available RESUMO O objetivo deste estudo foi classificar o antibiótico Terramicina(r de acordo com a toxicidade aguda e o risco de intoxicação ambiental para Oreochromis niloticus, Daphnia magna e Lemna minor, com base no seu ingrediente ativo oxitetraciclina (OTC. Além disso, observou-se a ocorrência de sinais de intoxicação aguda em peixes e o efeito da diluição do antibiótico sobre as variáveis de qualidade de água. Alevinos, neonatos e frondes foram expostos a concentrações de OTC. De acordo com os resultados dos testes de toxicidade aguda, a Terramicina(r foi classificada pela toxicidade aguda e pelo risco de intoxicação ambiental. Para O. niloticus, a CL(I50; 48h calculada foi de 6,92 mg L-1, para D. magna a CE(I50; 48h foi de 0,17mg.L-1, enquanto para L. minor a CI(I50;7d foi de 0,68 mg L-1. A Terramicina(r foi classificada como muito tóxica para O. niloticus e extremamente tóxica para D. magna e L. minor e causa risco de intoxicação ambiental para os três organismos testados. Concentrações de 7,5 e 8,0 mg L-1 de OTC reduziram a concentração de oxigênio dissolvido na água. De acordo com este estudo, a Terramicina(r não deve ser utilizada na aquicultura, pois é altamente tóxica e causa risco de intoxicação ambiental aos organismos teste.

Reproduction, food dynamics and exploitation level of Oreochromis niloticus (Perciformes: Cichlidae from artisanal fisheries in Barra Bonita Reservoir, Brazil

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José Luis Costa Novaes

2012-06-01

were phytoplankton and periphytic algae, observed in 99.6% of the analyzed stomachs. The estimated growth and mortality parameters were: L∞=33.60cm, k=0.63/year, longevity= 4.76years, Z=2.81/ year, M=1.20/year and F=1.61/year. The weight-length relationship was Ln Wt=-2.8532+2.8835 Ln Lp. The estimated yield per recruit values were as follows: E=0.570, Emax=0.776, E0.1=0.604 and E0.5=0.349. These results indicate that a well established population of O. niloticus is present at Barra Bonita Reservoir; with an active reproduction throughout the year, more intense during winter and spring, and that O. niloticus is a phytoplanktophagus species. There were no indications that this species is being overfished, we therefore recommend that, due to its exotic condition, no restrictions need to be taken on its fishing activities. Rev. Biol. Trop. 60 (2: 721-734. Epub 2012 June 01.La exótica tilapia del Nilo (Oreochromis niloticus es la especie mayormente capturada en la pesquería artesanal del embalse de Barra Bonita, sudeste de Brasil, de gran importancia socioeconómica para la región y para una población de unos 500 pescadores. El estudio analizo: la reproducción, la dinámica alimentaria y la explotación de O. niloticus, la cual fue capturada en la pesquería del embalse de Barra Bonita. Asimismo, se tomaron muestras mensuales y se analizo un total de 1 715 animales desde julio-2004 a junio-2005. De cada espécimen, se obtuvieron los siguientes datos biológicos y biométricos: longitud estándar (cm, peso total (g, datos reproductivos (sexo y estadio de maduración, contenido estomacal (vacio, parcialmente lleno y lleno. Estos datos fueron utilizados para estimar la proporción de sexo (a través de la observación macroscópica de las gónadas, el periodo reproductivo (a través de la distribución de la frecuencia de los estadios macroscópicos del desarrollo de los ovarios, y la media de la proporción del índice gonadosomático IGS de hembras, así como los h

Monthly variation in the Bioaccumulation of heavy metals and other safety issues in some marine and fresh water fish species in Ghana

International Nuclear Information System (INIS)

Arthur, W.

2014-07-01

Fish is one of the major sources of animal protein in Ghana and the fisheries industry is vital to the economy of the country. Unfortunately, most of the aquatic systems in Ghana are being polluted with domestic and industrial wastes which results in bioaccumulation of heavy metals in fish species. The traditional method for preserving fish in the country is by hot smoking or smoke drying, through freezing may be preferred where facilities are available. The presence of high levels of heavy metals in both fresh and smoked fish as well as other fish products is a matter of public health concern in Ghana. Variations in the level of bioaccumulation of heavy metals in both fresh and smoked marine fish, Sebastes marinus (red fish) and fresh water fish, Oreochromis niloticus (tilapia) caught off the coast of James Town in Accra and from the Volta river at Kpong respectively were monitored monthly from September 2013 to March 2014. Extension of two shelf life of the smoked fish species by gamma irradiation was also studied during 4 weeks of low temperature (5± 1 C ) storage by refrigeration. The total concentration of Iron (Fe), Zinc (Zn), Copper (Cu), Magnesium (Mg), Manganese (Mn), Cobalt (Co), Cadmium (Cd), Chromium (Cr), Arsenic (As) and Mercury (Hg) in the fish species as well as in their muscles, gills and bones were determined by Flame or Hydride Generation Atomic Absorption Spectrophotometry. The moisture content, pH, sensory analysis and population of aerobic mesophiles (on PCA), yeast and moulds (on OGYE), Escherichia coli (on EMB), Staphylococcus aureus (on BPA) and Salmonella (on XLD) in fresh fish, and smoked fish after treatment with 1, 2 and 3kGy of gamma irradiation and during storage were determined. Four patterns in the bioaccumulation of heavy metals in both Sebastes marinus and Oreochromis niloticus were observed over the 6 months monitoring period. Fe, Cu, Co and Cr accumulated heavily in the fish species during September and October after which the

Dietary phosphatidylcholine impacts on growth performance and lipid metabolism in adult Genetically Improved Farmed Tilapia (GIFT) strain of Nile tilapia Oreochromis niloticus.

Science.gov (United States)

Tian, Juan; Wen, Hua; Lu, Xing; Liu, Wei; Wu, Fan; Yang, Chang-Geng; Jiang, Ming; Yu, Li-Juan

2018-01-01

This study aimed to determine the effects of supplementing the diet of adult Nile tilapia Oreochromis niloticus with phosphatidylcholine (PC) on growth performance, body composition, fatty acid composition and gene expression. Genetically Improved Farmed Tilapia fish with an initial body weight of 83·1 (sd 2·9) g were divided into six groups. Each group was hand-fed a semi-purified diet containing 1·7 (control diet), 4·0, 6·5, 11·5, 21·3 or 41·0 g PC/kg diet for 68 d. Supplemental PC improved the feed efficiency rate, which was highest in the 11·5 g PC/kg diet. Weight gain and specific growth rate were unaffected. Dietary PC increased PC content in the liver and decreased crude fat content in the liver, viscera and body. SFA and MUFA increased and PUFA decreased in muscle with increasing dietary PC. Cytoplasmic phospholipase A 2 and secreted phospholipase A 2 mRNA expression were up-regulated in the brain and heart in PC-supplemented fish. PC reduced fatty acid synthase mRNA expression in the liver and visceral tissue but increased expression in muscle. Hormone-sensitive lipase and lipoprotein lipase expression increased in the liver with increasing dietary PC. Growth hormone mRNA expression was reduced in the brain and insulin-like growth factor-1 mRNA expression in liver reduced with PC above 6·5 g/kg. Our results demonstrate that dietary supplementation with PC improves feed efficiency and reduces liver fat in adult Nile tilapia, without increasing weight gain, representing a novel dietary approach to reduce feed requirements and improve the health of Nile tilapia.

Análise de parabenos em amostras de água de cultivo de tilápia do Nilo (Oreochromis niloticus) e efeitos em biomarcadores bioquímicos

OpenAIRE

Daniele Caetano da Silva

2015-01-01

Os parabenos utilizados como conservantes nas indústrias de cosméticos, alimentos e fármacos não são removidos por completo nas estações de tratamento de água e esgoto, além disso, podem causar danos a biota aquática. O presente estudo teve como finalidade aplicar um método analítico novo para quantificar o metil (MP), etil (EP), propil (PP), butil (BP), benzilparabeno (BzP) e a mistura (metil e propilparabeno) em amostras de água dos aquários com tilápias do Nilo (Oreochromis niloticus). A t...

Efeito da freqüência de alimentação no desempenho de larvas de tilápia do nilo, Oreochromis niloticus (L., durante a reversão sexual em tanques rede Effect of feeding frequency on Nile tilapia, Oreochromis niloticus (L. fries performance during sex reversal in hapas

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Carmino Hayashi

2001-05-01

Full Text Available Com o objetivo de testar a freqüência da alimentação necessária para o melhor desempenho de larvas de tilápia do Nilo, Oreochromis niloticus (Perciformes, Cichlidae, durante o período de reversão sexual em águas verdes, 1.600 larvas, com idade aproximada de 7 dias, pesando 9,77 mg e medindo 9,03 mm, na quantidade de 80 larvas/tanque rede, essas larvas foram alimentadas com ração de 43% PB, contendo 60 mg de metil testosterona/kg de ração, nas freqüências de 2, 3, 4, 5, e 6 alimentações/dia, divididas uniformemente, durante o período diurno, por 28 dias. Foram medidos os parâmetros de crescimento, sobrevivência, uniformidade, conversão alimentar e biomassa total produzida. O crescimento foi reduzido (P Research aimed at verifying the necessary feeding frequency for the best performance of Nile tilapia, Oreochromis niloticus (Perciformes, Cichlidae fries during sex reversal period in green waters. Approximately 1,600 seven-day-old fries, measuring 9.03mm and weighting 9.77mg, in a distribution of 80 fries/hapa, were fed on diet containing 43% of CP and 60mg of methyltestosterone/kg of diet at frequencies of 2, 3, 4, 5 and 6 feedings/day, divided equally over the light period, for 28 days. Parameters of growth, survival, uniformity, feed conversion and total biomass produced were measured. Growth was significantly (p < 0.05 reduced at the frequency of 2 times per day. Regression models were used to measure the effects of feeding frequency on total biomass, and on final average weight and length. Frequency of 4-to-5 feedings/day was the most adequate. Survival, variation coefficient, uniformity condition factor, feed conversion and cost variables were not affected by the feeding regimen. The results recommend the feeding of tilapia fries at least at 4 equally spaced times during the day during the sex reversal period in order to attain best performance.

Combination of physico-chemical analysis, Allium cepa test system and Oreochromis niloticus erythrocyte based comet assay/nuclear abnormalities tests for cyto-genotoxicity assessments of treated effluents discharged from textile industries.

Science.gov (United States)

Hemachandra, Chamini K; Pathiratne, Asoka

2016-09-01

Bioassays for cyto-genotoxicity assessments are generally not required in current textile industry effluent discharge management regulations. The present study applied in vivo plant and fish based toxicity tests viz. Allium cepa test system and Oreochromis niloticus erythrocyte based comet assay and nuclear abnormalities tests in combination with physico-chemical analysis for assessing potential cytotoxic/genotoxic impacts of treated textile industry effluents reaching a major river (Kelani River) in Sri Lanka. Of the treated effluents tested from two textile industries, color in the Textile industry 1 effluents occasionally and color, biochemical oxygen demand and chemical oxygen demand in the Textile industry 2 effluents frequently exceeded the specified Sri Lankan tolerance limits for discharge of industrial effluents into inland surface waters. Exposure of A. cepa bulbs to 100% and 12.5% treated effluents from both industries resulted in statistically significant root growth retardation, mito-depression, and induction of chromosomal abnormalities in root meristematic cells in comparison to the dilution water in all cases demonstrating cyto-genotoxicity associated with the treated effluents. Exposure of O. niloticus to the 100% and 12.5% effluents, resulted in erythrocytic genetic damage as shown by elevated total comet scores and induction of nuclear abnormalities confirming the genotoxicity of the treated effluents even with 1:8 dilution. The results provide strong scientific evidence for the crucial necessity of incorporating cyto-genotoxicity impact assessment tools in textile industry effluent management regulations considering human health and ecological health of the receiving water course under chronic exposure. Copyright © 2016 Elsevier Inc. All rights reserved.

Aprovechamiento de semillas de hule (Hevea brasiliensis L. para alimentación de tilapia (Oreochromis niloticus L.

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Gustavo Adolfo Elías-Ogaldez

2017-03-01

Full Text Available Se elaboró un concentrado artesanal para tilapia (Oreochromis niloticus L. con la finalidad de contribuir al aprovechamiento de los subproductos del cultivo de hule (Hevea brasiliensis Müll. Arg y de reducir los costos de producción de la tilapia. La investigación fue tipo aplicada y experimental, realizándose en la zona costera del Pacifico guatemalteco. Se concluyó que la harina de semilla de hule es un insumo apropiado para sustituir parcial o totalmente la harina de semilla de soya, en la formulación de concentrados artesanales para tilapia. Todos los tratamientos donde se utilizó harina de semilla de hule presentaron una mejor supervivencia y FCA frente al testigo. El tratamiento T3 presentó la mejor tasa de retorno marginal frente al testigo y los demás tratamientos. Por último, se recomienda continuar la investigación tomando en cuenta que la semilla de hule es deficiente en aminoácidos esenciales, los cuales se pueden adicionar para mejorar su rendimiento nutricional.

Análise tecidual e celular das brânquias de Oreochromis niloticus L. tratadas com extrato etanólico bruto e frações das folhas da pitanga (Eugenia uniflora L. - Myrtaceae Tissue and cell analysis of Oreochromis niloticus L. gill treated with crude ethanol extract and fractions from pitanga (Eugenia uniflora L. leaves Myrtaceae

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T.S. Fiuza

2011-01-01

have revealed in vitro antimicrobial activity of E. uniflora. Considering its popular use, this study aimed to assess possible systemic cellular and tissue activities of the crude extract and the fractions from the leaves of this plant on Oreochromis niloticus L. (Nile tilapia gill. Thus, ethanol extract and fractions from the leaves of this plant were orally administered to the fish in their rations. After 24 hours, the fish were sacrificed and the second gill arch of each fish was dissected, fixed in neutral formalin, dehydrated, embedded in paraffin and sectioned. Masson's trichome and hematoxylin and eosin (HE were used in the histological analyses. Qualitative analyses using a light microscope led to the conclusion that the crude ethanol extract and the fractions from E. uniflora leaves presented systemic effect on Nile tilapias, affecting the gills. Toxic actions such as respiratory epithelium detachment and lifting, and hyperplasia of interlamellar epithelial cells were more pronounced in the tilapias that ingested higher concentrations. This study helped to identify the vasodilator effect of this plant and contributed to the definition of the Nile tilapia as a model system for testing plant active principles. These tests are expected to make feasible not only the use of plants as fish medication but also the maintenance of the health of animals in intensive and extensive cultures through the possible use of alternatives to synthetic medication.

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

Molecular identification and histopathological study of natural Streptococcus agalactiae infection in hybrid tilapia (Oreochromis niloticus).

Science.gov (United States)

Laith, A A; Ambak, Mohd Azmi; Hassan, Marina; Sheriff, Shahreza Md; Nadirah, Musa; Draman, Ahmad Shuhaimi; Wahab, Wahidah; Ibrahim, Wan Nurhafizah Wan; Aznan, Alia Syafiqah; Jabar, Amina; Najiah, Musa

2017-01-01

The main objective of this study was to emphasize on histopathological examinations and molecular identification of Streptococcus agalactiae isolated from natural infections in hybrid tilapia ( Oreochromis niloticus ) in Temerloh Pahang, Malaysia, as well as to determine the susceptibility of the pathogen strains to various currently available antimicrobial agents. The diseased fishes were observed for variable clinical signs including fin hemorrhages, alterations in behavior associated with erratic swimming, exophthalmia, and mortality. Tissue samples from the eyes, brain, kidney, liver, and spleen were taken for bacterial isolation. Identification of S. agalactiae was screened by biochemical methods and confirmed by VITEK 2 and 16S rRNA gene sequencing. The antibiogram profiling of the isolate was tested against 18 standard antibiotics included nitrofurantoin, flumequine, florfenicol, amoxylin, doxycycline, oleandomycin, tetracycline, ampicillin, lincomycin, colistin sulfate, oxolinic acid, novobiocin, spiramycin, erythromycin, fosfomycin, neomycin, gentamycin, and polymyxin B. The histopathological analysis of eyes, brain, liver, kidney, and spleen was observed for abnormalities related to S. agalactiae infection. The suspected colonies of S. agalactiae identified by biochemical methods was observed as Gram-positive chained cocci, β-hemolytic, and non-motile. The isolate was confirmed as S. agalactiae by VITEK 2 (99% similarity), reconfirmed by 16S rRNA gene sequencing (99% similarity) and deposited in GenBank with accession no. KT869025. The isolate was observed to be resistance to neomycin and gentamicin. The most consistent gross findings were marked hemorrhages, erosions of caudal fin, and exophthalmos. Microscopic examination confirmed the presence of marked congestion and infiltration of inflammatory cell in the eye, brain, kidney, liver, and spleen. Eye samples showed damage of the lens capsule, hyperemic and hemorrhagic choroid tissue, and retina

Molecular identification and histopathological study of natural Streptococcus agalactiae infection in hybrid tilapia (Oreochromis niloticus

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Laith Abdul Razzak

2017-01-01

Full Text Available Aim: The main objective of this study was to emphasize on histopathological examinations and molecular identification of Streptococcus agalactiae isolated from natural infections in hybrid tilapia (Oreochromis niloticus in Temerloh Pahang, Malaysia, as well as to determine the susceptibility of the pathogen strains to various currently available antimicrobial agents. Materials and Methods: The diseased fishes were observed for variable clinical signs including fin hemorrhages, alterations in behavior associated with erratic swimming, exophthalmia, and mortality. Tissue samples from the eyes, brain, kidney, liver, and spleen were taken for bacterial isolation. Identification of S. agalactiae was screened by biochemical methods and confirmed by VITEK 2 and 16S rRNA gene sequencing. The antibiogram profiling of the isolate was tested against 18 standard antibiotics included nitrofurantoin, flumequine, florfenicol, amoxylin, doxycycline, oleandomycin, tetracycline, ampicillin, lincomycin, colistin sulfate, oxolinic acid, novobiocin, spiramycin, erythromycin, fosfomycin, neomycin, gentamycin, and polymyxin B. The histopathological analysis of eyes, brain, liver, kidney, and spleen was observed for abnormalities related to S. agalactiae infection. Results: The suspected colonies of S. agalactiae identified by biochemical methods was observed as Gram-positive chained cocci, β-hemolytic, and non-motile. The isolate was confirmed as S. agalactiae by VITEK 2 (99% similarity, reconfirmed by 16S rRNA gene sequencing (99% similarity and deposited in GenBank with accession no. KT869025. The isolate was observed to be resistance to neomycin and gentamicin. The most consistent gross findings were marked hemorrhages, erosions of caudal fin, and exophthalmos. Microscopic examination confirmed the presence of marked congestion and infiltration of inflammatory cell in the eye, brain, kidney, liver, and spleen. Eye samples showed damage of the lens capsule

Morphometrics, fillet yield and fillet composition in Nile tilapia, Oreochromis niloticus, strains thai chitralada, Brazil local and their hybrid/ Características morfométricas, rendimento e composição do filé de tilápia do Nilo, Oreochromis niloticus, da linhagem tailandesa, local e do cruzamento de ambas

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Aleksey Machado Moreno

2006-06-01

Full Text Available Morphometrics, fillet yield and fillet composition differences were researched in Nile tilapia, Oreochromis niloticus, strain thai-chitralada (Tai, Brazil (Local Northern Paraná and their hybrid (Hbr, male Thailand x Brazilians female . The experiment was designed entirely randomly with three treatments (strains andthree repetitions per treatment in hapa nets in ponds. The initial weights were 0.39 ± 0.20, 0.45 ± 0.22 and 0.41 ± 0.15 g for the strains Tai, Bras and Hbr, respectively. At the end of the experiment, the weights were 650.67, 534.25 and 360.00 g for the same previous sequence, with statistically significant differencesbetween groups (P0.05. The strain Hbr produced (P0.05. Considering fillet composition, Local strain had the least crude lipid content of (1.88 %, as compared to Hbr (2.44 % and Tai (2.96 % which were significantly different (P 0.05.As características morfométricas, rendimento e a composição do filé foram pesquisadas em tilápia do Nilo Oreochromis niloticus, das linhagens tailandesa chitralada (Tai, local (Local, Norte do Paraná, Brasil, e da proveniente do cruzamento de ambas (Hbr, macho tailandesa x fêmea local. Ao início do experimento os peixes (n: 900 apresentavam peso de 0,39 ± 0,20; 0,41 ± 0,22 e 0,45 ± 0,15 g e ao final 650,67; 534,25 e 360,00 g para as variedades Tai, Local e Hbr, respectivamente. Foram estabelecidas quatro razões morfométricas, sendo que a razão entre a altura da cabeça/ comprimento da cabeça da variedade Tai foi maior (P 0,05. A composição centesimal do filé da linhagem Local apresentou menor teor de lipídeos (1,88% (P 0,05 entre as variedades.

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

Técnicas de controle de qualidade utilizadas na criação de tilápia do Nilo (Oreochromis niloticus - DOI: 10.4025/actascibiolsci.v20i0.4471 Quality control techniques used in the breeding of Nile tilapia (Oreochromis niloticus - DOI: 10.4025/actascibiolsci.v20i0.4471

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Júlio Hermann Leonhardt

1998-07-01

Full Text Available Foram utilizados 240 alevinos de tilápia do Nilo (Oreochromis niloticus, de 45 dias, sexualmente revertidos com peso médio inicial de 1,25 ± 0,14g, distribuídos num delineamento inteiramente casualizado, durante 180 dias. Foram avaliados os efeitos da substituição de 10%, 20% e 30% da ração por levedura de destilaria alcooleira. Os resultados médios obtidos para os parâmetros limnológicos no controle da qualidade da água através de análises físico-químicas e gráficos de controle foram normais durante todo o período experimental. Os valores da temperatura média mensal revelaram estar “fora de controle estatístico”, e mostraram, através da aplicação dos índices de capacidade (Cp e Cpk, que 35,20% estão abaixo do limite inferior de especificação (LIE. A análise dos resultados obtidos, através da aplicação das técnicas de Pareto e Problema da Mochila, evidenciou a solução ótima para resolver os problemas de predadores, biometrias e doenças com a função objetivo Z* maximizada. A utilização das técnicas de controle de qualidade permite um aumento da taxa de estocagem nos tanques sem redução da taxa de crescimento individual e com obtenção de altas produções de peixes de boa qualidade.Two hundred and forty Nile tilapia fry (Oreochromis niloticus, 45 days old, sexually reverted, with initial average weight of 1.25 ± 0.14g, distributed in a totally randomized design during 180 days, were used in this experiment. Effects of substitutions of 10%, 20% and 30% of the rations by yeast obtained from alcohol distillery were evaluated. Average results obtained for the limnological parameters in water quality control by means of chemical analyses and control graphs were considered normal during the entire experimental period. Values of monthly average temperature were statistically out of control and by the application of the capacity rates (Cp and Cpk showed that 35.20% were below the lowest specification limit

Integrated Multi-Trophic Recirculating Aquaculture System for Nile Tilapia (Oreochlomis niloticus

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Puchong Sri-uam

2016-06-01

Full Text Available Three densities of the sex-reversed male Nile tilapia, Oreochromis niloticus (20, 25, 50 fish/m3 were cultivated in an integrated multi-trophic recirculating aquaculture system (IMRAS that involves the ecological relationship between several living organisms, i.e., phytoplankton, zooplankton, and aquatic plants. The results indicated that, by providing proper interdependency between various species of living organisms, the concentrations of ammonia, nitrite, nitrate, and phosphate in the system were maintained below dangerous levels for Nile tilapia throughout the cultivation period. The highest wet weight productivity of Nile tilapia of 11 ± 1 kg was achieved at a fish density of 50 fish/m3. The aquatic plants in the treatment tank could effectively uptake the unwanted nitrogen (N and phosphorus (P compounds with the highest removal efficiencies of 9.52% and 11.4%, respectively. The uptake rates of nitrogen and phosphorus by aquatic plants could be ranked from high to low as: Egeria densa > Ceratophyllum demersum > Vallisneria spiralis and Vallisneria americana > Hygrophila difformis. The remaining N was further degraded through nitrification process, whereas the remaining P could well precipitate in the soil sediment in the treatment tank.

Fatty acids of polar lipids in heart tissue are good taxonomic markers ...

African Journals Online (AJOL)

The fatty acid profiles in total, neutral and polar lipids in the heart tissues of five freshwater fish species (Nile perch Lates niloticus, Nile tilapia Oreochromis niloticus, marbled lungfish Protopterus aethiopicus, Bagrus docmak and African catfish Clarias gariepinus) from Lakes Victoria and Kyoga were determined ...

Edad y crecimiento del híbrido de tilapia Oreochromis niloticus x Oreochromis aureus (Perciformes: Cichlidae en la represa “Zimapán” Hidalgo, México

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M. A. Gómez-Ponce

2011-06-01

Full Text Available La edad y crecimiento de la tilapia Oreochromis niloticus x Oreochromis aureus fueron determinados por medio de la lectura de escamas. Un total de 382 individuos fueron capturados mediante el uso de redes agalleras y atarrayas. Ocho recolectas mensuales se llevaron a cabo entre septiembre 2003-mayo 2004; se registraron los datos de longitud estándar en cm. (Le, el peso total en g (Pt y se obtuvieron muestras de escamas para registrar el largo de la escama en mm. (Lesc y el número de anillos de crecimiento formados. Las tallas y pesos de recolecta variaron entre 38 a 232mm (Le y de 8.7 a 311.9g de peso total (Pt respectivamente. El recuento de los anillos anuales en escamas, permitió establecer cuatro grupos de edad, siendo el grupo de edad 2 el más representativo, con un 34.3% de la población muestreada. El cálculo de los incrementos marginales del crecimiento mensual de las escamas, sugirió la formación de dos anillos, uno de ellos se forma en los meses de noviembre-enero y otro en los meses de abril-mayo, los cuales coinciden con la época de bajas temperaturas y de madurez gonádica respectivamente. Los parámetros de crecimiento quedaron establecidos en: L∞=281.1mm, W∞=877.1g, K=0.33 y T0=0.88/año. Las curvas de crecimiento en longitud y peso se describieron mediante las ecuaciones de von Bertalanffy: Le=28.11 [1- e-0.33(t+0.88] y Pt=877.17 [1-e-0.33(t+0.88]³. Finalmente, se concluyó que los peces que se explotan en la represa mediante captura comercial presentan entre un año y año y medio de edad.

Physiological and haematological response of Oreochromis niloticus (Osteichthyes: Cichlidae exposed to single and consecutive stress of capture - DOI: 10.4025/actascianimsci.v26i4.1719 Resposta fisiológica e hematológica de Oreochromis niloticus (Osteichthyes: Cichlidae exposto ao estresse único e consecutivo de captura - DOI: 10.4025/actascianimsci.v26i4.1719

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Karina Ribeiro

2004-04-01

Full Text Available This work is a sequence of studies on tropical fish of economic importance that evaluated the effects of two different stress of handling on the physiology and haematology of Oreochromis niloticus L. acclimated for 10 days before the essay. The stress consisted in net capture of all fish from each aquarium for 30s emersion. Fish exposed to single stress (SS the samples were collected in the times 0, 10, 20, 30, 40, 50, 60, 120, 180, 240 and 300min. after stress. In the consecutive stress (CS the samples were collected in the times 0; 15min. after the first stress; 15min. after the second stress; 15min. after the third stress and 15, 30, 45, 60, 120, 180 e 240min. after the fourth stress totalizing four stimuli every 60min. Fish exposed to SS showed increased cortisol and glucose concentrations at 60min. as well as in the leucocytes number and hematocrit at 50min. after stress. Cortisol did not alter in fish exposed to CS, but glucose increased 15min. after the third stress. On the other hand, CS provoked reduction in the leucocytes number and later hematocrit increasing. Neutrophilia and lymphopenia were related to SS and CS.Este trabalho é seqüência de estudos com peixes tropicais de importância econômica avaliando os efeitos de dois tipos de estresse sobre a fisiologia e hematologia de O. niloticus L, aclimatados durante 10 dias antes do experimento. O estresse consistiu na captura de todos os peixes do aquário com rede e emersão por 30 s. Nos animais submetidos ao estímulo único de captura (EU as amostras foram coletadas nos tempos 0, 10, 20, 30, 40, 50, 60, 120, 180, 240 e 300min. após o estresse. No estímulo consecutivo (EC as amostras foram coletadas nos tempos 0; 15min. após o primeiro estresse; 15min. após o segundo estresse; 15min. após o terceiro estresse e 15, 30, 45, 60, 120, 180 e 240min. após o quarto estresse totalizando quatro estímulos a cada 60min. Os peixes expostos ao EU apresentaram aumento nas concentra

The patterns and trends of marketing and consumption of the fish of Lake Victoria (Kenya waters). Paper presented at FISA 95: Inaugural Congress of the Fisheries Society for Africa (FISA '95),UNEP Nairobi, Kenya, 31 July - 5th August, 1995.

OpenAIRE

Abila, R.

1995-01-01

Lake Victoria, producing over 90% of Kenya's fish, is the principle source of fish for domestic consumption and for export in the country. The three fish species of most economic importance are Lates niloticus, Rastrineobola argentea and Oreochromis species. These constitute 50%, 37% and 6% respectively of the lakes's tonnage. The structure and performance of the marketing system for each of these species differ, depending on certain market features. Among these are the marketing history and ...

Centrocestus formosanus (Opisthorchiida: Heterophyidae como causa de muerte de alevines de tilapia gris Oreochromis niloticus (Perciforme: Cichlidae en el Pacífico seco de Costa Rica

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Donald Arguedas Cortés

2010-12-01

Full Text Available Centrocestus formosanus es un parásito trematodo zoonótico originario de Asia asociado con muertes de peces principalmente de cultivo. 907 moluscos provenientes de estanques sembrados con tilapias, seleccionados uno por provincia fueron identificados al nivel taxonómico especifico. Se identificaron cuatro gastrópodos y un bivalvo: M. tuberculata, M. turricula, P. flagellata, H. cubensis y A. luteola. Se reporta, por primera vez, la presencia de dos especies de moluscos en Costa Rica. Se identificaron siete morfotipos de cercarias parasitando las cinco especies de moluscos encontradas. En la segunda exposición experimental se demostró que el morfotipo parapleurolofocercus encontrado en M. tuberculata concuerda con el hallazgo de C. formosanus en alevines de tilapia, después del examen clínico, anatomopatológico y parasitológico realizado a los alevines expuestos. Las metacercarias fueron extraídas del quiste utilizando microagujas y micropinzas lavadas en solución salina fisiológica (0.65%, fijadas en formol caliente al 4% y después esquematizadas con una cámara clara adaptada a un microscopio fotónico, estimándose una abundancia e intensidad media de 1018-1027 digeneos por branquia en cada pez parasitado, determinándose así el hospedador intermediario primario y secundario del parásito. En el presente trabajo se reporta por primera vez Centrocestus formosanus en Costa Rica.Centrocestus formosanus (Opisthorchiida: Heterophyidae as a cause of death in gray tilapia fry Oreochromis niloticus (Perciforme: Cichlidae in the dry Pacific of Costa Rica. Centrocestus formosanus is a zoonotic trematode from Asia and has been mainly associated as cause of death of cultured fish. To identify pathogen trematode species in tilapia fry (Oreochromis niloticus and to determine mollusks hosting these parasites, freshwater mollusks were collected from tilapia cultured ponds and experimental infections were carried out with tilapia fries and

Growth Performance, Yields and Economic Benefits of Nile Tilapia ...

African Journals Online (AJOL)

fish culture integration in the growth, yields and economic benefits of fish and vegetables. Two 200 m2 earthen fishponds were stocked with Nile tilapia Oreochromis niloticus at 20,000 fish fingerlings per hectare. Pond A was fertilized with ...

Micronucleus test in fish genome: A sensitive monitor for aquatic ...

African Journals Online (AJOL)

The aquatic environment makes up the major part of our environment and resources, therefore its safety is directly related to the safety our health. In this study, three tilapia species (Oreochromis niloticus, Oreochromis aureus and Tilapia zilli) and Clarias gariepinus were employed to estimate water pollution using ...

Effects of Olea europaea L. Leaf Metabolites on the Tilapia (Oreochromis niloticus and Three Stored Pests, Sitophilus granarius, Tribolium confusum and Acanthoscelides obtectus

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Ahmet Kısa

2018-05-01

Full Text Available Olea europea L. emerged as a good source of traditional medicine for the treatment of various ailments of various countries of the world, in particular Mediterranean countries. In this study, oleuropein (1, oleanolic acid (2, maslinic acid (3, a mixture of erythrodiol and uvaol (4 and 5 isolated from the leaves of olive were added at two concentrations (1g/100g feed and 4g/100 g feed into fish feed. Oreochromis niloticus (Nile tilapia were fed twice a day with the feed during 96 hours. The levels of alanine aminotransferase (ALT, aspartate aminotransferase (AST, alkaline phosphatase (ALP enzymes and glucose levels in the serums of fishes fed with pure compounds were found to be higher as compared with the control group. Pure metabolites affect the liver metabolism of Nile tilapia. These results suggested that the compounds tested affect the liver metabolism of Nile tilapia. Compounds 1, 2, 3 and 4+5 (2.5, 5.0 and 7.5 mg/Petri dish concentrations were also tested for contact toxic effects against three important stored pests, Sitophilus granarius (weevil, Tribolium confusum (confused flour beetle and Acanthoscelides obtectus (bean weevil. The toxic effects of the metabolites were lower than those of the insecticide, dichlorvos (DDVP. DDVP caused complete mortality of the insects after 48 hours of treatments, the metabolites caused the mortality rates 16.7-63.3 %, 13.3-67.0 % and 26.7-59.0 % of S. granarius, T. confusum and A. obtectus, respectively. Maslinic acid (3 has the most toxic compound with the lowest LC 50 values (0.66 mg/Petri, 0.61 mg/Petri and 1.71 mg/Petri for S. granarius, T. confusum and A. obtectus, respectively. These results show that maslinic acid (3 as well as other substances can be used as natural insecticides against these pests.

Ectoparasitos de tilápia do Nilo (Oreochromis niloticus, das linhagens Chitralada e GIFT, em diferentes densidades e alimentadas com dois níveis de proteína - DOI: 10.4025/actascianimsci.v29i4.1015 Ectoparasites in Nile tilapia (Oreochromis niloticus from Chitralada and GIFT strains, in different densities, fed with two protein levels - DOI: 10.4025/actascianimsci.v29i4.1015

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Maria de los Angeles Peres Lizama

2008-03-01

Full Text Available Foi verificada a infestação por ectoparasitos em tilápia do Nilo (Oreochromis niloticus, nas linhagens Chitralada e GIFT, em tanques e viveiros, utilizando-se ração com dois níveis de proteína. Durante o ensaio, foram analisados a temperatura, o pH, o oxigênio dissolvido e a condutividade elétrica. Foram realizadas amostras de raspados de tegumento e brânquias de machos pós-revertidos, em duas fases do experimento. A primeira, em 240 alevinos provenientes de 18 caixas de fibra de vidro de 500 L em três densidades. A prevalência total de parasitos na linhagem Chitralada (densidades de 30, 40 e 50 peixes m-3 foi 72,2, 83,3 e 59,5%, com predominância de Trichodina (38,9, 63,3 e 26,2%, respectivamente. Para a linhagem GIFT, nas mesmas densidades, foram observados 83,3, 73,3 e 80,9%, com maior predominância também de Trichodina (33,3, 73,3 e 45,2%, respectivamente. Na segunda fase, foram analisados 90 peixes de cada linhagem, de dois viveiros (140 m2 e duas dietas com 25 e 30% de proteína bruta. A prevalência total, para as linhagens Chitralada e GIFT com 25% PB foi 86,7 e 76,7%, respectivamente, e para 30% PB foi 60,0%, para ambas as linhagens. O nível de 30% PB, independentemente da linhagem, apresentou a menor prevalência parasitária.Ectoparasites infestation in Nile Tilapia (Oreochromis niloticus was observed in Chitralada and GIFT strains cultivated in cages and ponds, using rations with two protein levels. During the assay, temperature, pH, dissolved oxygen and electric conductivity were analyzed. Tegument scraping and gill samples from reverted males were evaluated, in two experiment phases. The first phase was carried out with 240 fingerlings from 18 500 L fiberglass boxes using three stocking densities. Total prevalence of parasites in the Chitralada strain (stocking density of 30, 40 and 50 fish m-3 was 72.2, 83.3 and 59.5%, with Trichodina predominance (38.9, 63.3 and 26.2%, respectively. For the GIFT strain, at the

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

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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.

EFEITO DO LACTOBACILLUS PLANTARUM NO TRATO INTESTINAL DE ALEVINOS DE OREOCHROMIS NILOTICUS

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José Luís Pedreira Mouriño

2015-01-01

Full Text Available The objective of this study was to evaluate alterations in the intestinal tract microbiota and growth performance of Nile tilapia (Orechromis niloticus fed diets supplemented with Lactobacillus plantarum. One hundred and twenty sexually reversed fingerlings were stocked in six aquaria and divided into two treatments, in triplicate: fingerlings fed diet supplement with L. plantarum and fingerlings fed control diet. After 42 days, tilapia fed the diet supplemented with L. plantarum had higher amount of lactic acid bacteria, 3,5x104 CFU and 1,1x102 CFU per g tract, and lower total bacteria, 5,8x106 CFU and 5,2x107 CFU per g tract, than the fish fed the control diet. Furthermore, probiotics increased 3,9% the weekly weight gain, 15,6% final biomass and 15,5% feed efficiency. The use of probiotics in tilapia hatcheries boosts productivity.

Caracterización de tilapia roja (Oreochromis sp. con marcadores moleculares RAPD

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Julieta Torres Jaramillo

2010-04-01

Full Text Available Se utilizó la técnica RAPD (amplificación al azar de ADN polimórfico para el estudio de la diversidad genética de Oreochromis sp. (tilapia roja en cinco piscícolas del Valle del Cauca (Colombia y en la determinación del nivel de introgresión de las especies parentales Oreochromis mosambicus, O. niloticus y O. aureus. Se evaluaron 25 cebadores, ocho fueron polimórficos y se obtuvieron 109 bandas. Los valores de heterocigosidad esperada (0.196 a 0.256 y la estructura genética (Gst = 0.22 para Oreochromis sp. indicaron un elevado grado de polimorfismo y alta estructuración genética. Estos resultados fueron consistente con el Fst = 0.268 (P < 0.0001 dado por el Amova y el Gst = 0.040 del análisis de correspondencia múltiple. Los valores de similitud genética, el análisis de grupo, el análisis de correspondencia múltiple y el nivel de introgresion, indicaron diferencias significativas (P<0.0001 en los niveles de introgresión. El bajo nivel de diferenciación genética entre poblaciones podría ser el resultado de peces con el mismo origen genético y la alta variación dentro de poblaciones se puede presentar por prácticas de manejo. La introgresión entre piscícolas es significativa para O. aureus, mientras que las especies O. niloticus y O. mosambicus se encuentran introgresadas de forma similar en las poblaciones de Oreochromis sp.

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.

Estimativa da variabilidade genética em linhagens de tilápia do Nilo (Oreochromis niloticus com a técnica de RAPD - DOI: 10.4025/actascianimsci.v27i1.1236 Genetic variability estimation of Nile tilapia strains (Oreochromis niloticus using the RAPD technique - DOI: 10.4025/actascianimsci.v27i1.1236

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Lauro Vargas

2005-03-01

Full Text Available A variabilidade genética é essencial para que se possa obter melhoramento genético e, portanto, é de grande importância a sua estimação. Desta forma, o objetivo do presente experimento foi estimar, pela técnica Random Amplified Polymorphic DNA (RAPD, a divergência e a variabilidade genética nas linhagens de tilápias do Nilo (Oreochromis niloticus Bouaké e Chitralada em duas gerações de reprodutores do rio Nilo. Foram utilizados 20 animais de cada linhagem. A matriz de coeficientes de similaridade de Jaccard entre indivíduos foi utilizada para a construção de um dendrograma e para a determinação, com o teste de Mantel, da divergência genética entre linhagens. A variabilidade genética foi estimada pelo índice de Shannon e pela porcentagem de loci polimórficos. As linhagens Bouaké e Chitralada formaram grupos distintos. A primeira apresentou menor divergência e variabilidade genética em relação à segunda. A variabilidade genética foi semelhante entre as duas gerações de reprodutores em ambas as linhagensGenetic variability estimation is highly important in order to achieve genetic improvement. The present experiment aims at estimating the genetic divergence and variability of the Nile tilapia strains (Oreochromis niloticus, Bouaké and Chitralada, in two breeders offsprings, using the Random Amplified Polymorphic DNA (RAPD. Twenty animals from each strain were used. The Jaccard similarity coefficients matrix was used for both designing a dendrogram and determining the genetic divergence of the strains, using Mantel’s test. The genetic variability was estimated by Shannon’s index and the percentage of polymorphic loci. Bouaké and Chitralada’s strains formed different groups. The former strain showed lower genetic divergence and variability in relation to the latter one. The two breeders offsprings had similar genetic variability in both strains

Persamaan Prediksi Umur Simpan Filet Ikan Nila (Oreochromis niloticus yang Dikemas Vakum dalam HDPE

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Rudi Riyanto

2014-06-01

Full Text Available Penelitian ini dilakukan untuk mendapatkan data laju penurunan mutu filet ikan nila (Oreochromis niloticus yang dikemas vakum dengan HDPE. Hasil analisis digunakan untuk menentukan indikator yang paling tepat untuk persamaan prediksi umur simpan menggunakan persamaan regresi. Dalam percobaan yang dilakukan filet ikan nila yang dikemas vakum dengan HDPE disimpan pada suhu 0, 10, 20, dan 30 oC. Parameter yang dianalisis adalah TVB-N, pH, TBA, Organoleptik (hedonik, dan TPC (aerob dan anaerob. Data yang dihasilkan menunjukkan bahwa suhu dan lama penyimpanan berpengaruh nyata terhadap laju penurunan mutu filet ikan nila (P<0,05. Berdasarkan tingkat kecepatan parameter mutu untuk mencapai limit toleransi, nilai TVB-N merupakan parameter mutu yang paling tepat untuk dijadikan parameter penentu kinetika pembusukan filet ikan nila. Kandungan TVB filet ikan nila yang disimpan pada suhu 30, 20, 10, dan 0 °C telah melampaui batas mutu (30 mg-N/100 g secara berturut-turut pada penyimpanan 9, 24, 72, dan 168 jam. Berdasarkan hasil pengolahan data nilai TVB filet ikan nila pada beberapa suhu penyimpanan menggunakan persamaan Arrhenius, nilai Ea yang didapatkan sebesar 72,17 KJ/mol dengan menggunakan nilai TVB 30 mg-N/100 g sebagai nilai batas penolakan mutu filet ikan nila. Persamaan prediksi umur simpan (t=jam filet ikan nila dalam HDPE vakum yang didapatkan adalah ln A = ln A0 + (t.exp[26,44-8681(1/T] dengan tingkat akurasi nilai prediksi terhadap nilai mutu filet ikan nila percobaan adalah 73–78%.

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The sex-ratio of most fish in the lake tends to unity (1:1), suggesting reproductive stability. Condition factors are high for the fish species ... Parachanna obscuraGunther. Snake head. Characidae. Chrysichthys auratusPfaff. Characines. Cichlidae. Hemichromis faciatusPeter. Banded jewel fish. Oreochromis niloticusLinnaeus.

The effect of different protein sources in supplementary feeds on ...

African Journals Online (AJOL)

The effect of locally available protein sources including fish meal (FM), soyabean meal (SBM), groundnut cake (GNC), and blood meal (BM)) at 25% inclusion level in pelleted 'feed layers concentrate/corn bran in ratio 1:3, and premix 1.0%) were tested on tilapia (Oreochromis niloticus) in floating net-cages. O. niloticus ...

II. Application of genetically modified breeding by introducing foreign ...

African Journals Online (AJOL)

Production of salinity tolerant Nile tilapia, Oreochromis niloticus through traditional and modern breeding methods: II. Application of genetically modified breeding by introducing foreign DNA into fish gonads.

Comparison of antimicrobial activities of brine salting, Chlorinated ...

African Journals Online (AJOL)

Chemical preservatives can be used to reduce the overall microbial populations in fish and fish products. This study was set to determine the antimicrobial activities of brine salting, chlorinated solution, and Moringa oleifera plant extracts treatments on enteric bacteria in Rastrineobola argentea and Oreochromis niloticus fish ...

Chemical communication in tilapia: a comparison of Oreochromis mossambicus with O. niloticus.

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Hubbard, Peter C; Mota, Vasco C; Keller-Costa, Tina; da Silva, José Paulo; Canário, Adelino V M

2014-10-01

In allopatric speciation species differentiation generally results from different selective pressures in different environments, and identifying the traits responsible helps to understand the isolation mechanism(s) involved. Male Mozambique tilapia (Oreochromis mossambicus) use urine to signal dominance; furthermore, 5β-pregnane-3α,17,20β-triol-3α-glucuronide (and its α-epimer, 5β-pregnane-3α,17,20α-triol-3α-glucuronide), in their urine is a potent pheromone, the concentration of which is correlated with social status. The Nile tilapia (Oreochromisniloticus) is a close relative; species divergence probably resulted from geographical separation around 6 million years ago. This raises the question of whether the two species use similar urinary chemical cues during reproduction. The olfactory potency of urine, and crude extracts, from either species was assessed by the electro-olfactogram and the presence of the steroid glucuronides in urine from the Nile tilapia by liquid-chromatography/mass-spectrometry. Both species showed similar olfactory sensitivity to urine and respective extracts from either species, and similar sensitivity to the steroid glucuronides. 5β-Pregnan-3α,17α,20β-triol-3α-glucuronide was present at high concentrations (approaching 0.5mM) in urine from Nile tilapia, with 5β-pregnan-3α,17α,20α-triol-3α-glucuronide present at lower concentrations, similar to the Mozambique tilapia. Both species also had similar olfactory sensitivity to estradiol-3-glucuronide, a putative urinary cue from females. Together, these results support the idea that reproductive chemical cues have not been subjected to differing selective pressure. Whether these chemical cues have the same physiological and behavioural roles in O. niloticus as O. mossambicus remains to be investigated. Copyright © 2014 Elsevier Inc. All rights reserved.

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.

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.

Experimental assessment of the effects of a Neotropical nocturnal piscivore on juvenile native and invasive fishes

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Alejandra F. G. N. Santos

Full Text Available We experimentally examined the predator-prey relationships between juvenile spotted sorubim Pseudoplastystoma corruscans and young-of-the-year invasive and native fish species of the Paraná River basin, Brazil. Three invasive (peacock bass Cichla piquiti, Nile tilapia Oreochromis niloticus, and channel catfish Ictalurus punctatus and two native (yellowtail tetra Astyanax altiparanae and streaked prochilod Prochilodus lineatus fish species were offered as prey to P. corruscans in 300 L aquaria with three habitat complexity treatments (0%, 50% and 100% structure-covered. Prey survival was variable through time and among species (C. piquiti < O. niloticus < A. altiparanae < P. lineatus < I. punctatus, depending largely on species-specific prey behavior but also on prey size and morphological defenses. Habitat complexity did not directly affect P. corruscans piscivory but some prey species changed their microhabitat use and shoaling behavior among habitat treatments in predator's presence. Pseudoplatystoma corruscans preyed preferentially on smaller individuals of those invasive species with weak morphological defensive features that persisted in a non-shoaling behavior. Overall, our results contrast with those in a companion experiment using a diurnal predator, suggesting that nocturnal piscivores preferentially prey on different (rather diurnal fish species and are less affected by habitat complexity. Our findings suggest that recovering the native populations of P. corruscans might help controling some fish species introduced to the Paraná River basin, particularly C. piquiti and O. niloticus, whose parental care is expected to be weak or null at night.

Caracterización de tilapia roja (Oreochromis sp. con marcadores moleculares RAPD

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Muñoz Jaime Eduardo

2010-06-01

Full Text Available Se utilizó la técnica RAPD (amplificación al azar de ADN polimórfico para el estudio de la diversidad genética de Oreochromis sp. (tilapia roja en cinco piscícolas del Valle del Cauca (Colombia y en la determinación del nivel de introgresión de las especies parentales Oreochromis mosambicus, O. niloticus y O. aureus. Se evaluaron 25 cebadores, ocho fueron polimórficos y se obtuvieron 109 bandas. Los valores de heterocigosidad esperada (0.196 a 0.256 y la estructura genética (G_st = 0.22 para Oreochromis sp. indicaron un elevado grado de polimorfismo y alta estructuración genética. Estos resultados fueron consistente con el F_st = 0.268 (P < 0.0001 dado por el Amova y el G_st = 0.040 del análisis de correspondencia múltiple. Los valores de similitud genética, el análisis de grupo, el análisis de correspondencia múltiple y el nivel de introgresion, indicaron diferencias significativas (P<0.0001 en los niveles de introgresión. El bajo nivel de diferenciación genética entre poblaciones podría ser el resultado de peces con el mismo origen genético y la alta variación dentro de poblaciones se puede presentar por prácticas de manejo. La introgresión entre piscícolas es significativa para O. aureus, mientras que las especies O. niloticus y O. mosambicus se encuentran introgresadas de forma similar en las poblaciones de Oreochromis sp.

Depletion of florfenicol amine in tilapia (Oreochromis sp.) maintained in a recirculating aquaculture system following Aquaflor®-medicated feed therapy

Science.gov (United States)

Gaikowski, Mark P.; Whitsel, Melissa K.; Charles, Shawn; Schleis, Susan M.; Crouch, Louis S.; Endris, Richard G.

2015-01-01

Aquaflor® [50% w w−1 florfenicol (FFC)], is approved for use in freshwater-reared warmwater finfish which include tilapia Oreochromis spp. in the United States to control mortality from Streptococcus iniae. The depletion of florfenicol amine (FFA), the marker residue of FFC, was evaluated after feeding FFC-medicated feed to deliver a nominal 20 mg FFC kg−1 BW d−1 dose (1.33× the label use of 15 mg FFC kg−1 BW d−1) to Nile tilapia O. niloticus and hybrid tilapia O. niloticus × O. aureus held in a recirculating aquaculture system (RAS) at production-scale holding densities. Florfenicol amine concentrations were determined in fillets taken from 10 fish before dosing and from 20 fish at nine time points after dosing (from 1 to 240 h post-dosing). Water samples were assayed for FFC before, during and after the dosing period. Parameters monitored included daily feed consumption and biofilter function (levels of ammonia, nitrite and nitrate). Mean fillet FFA concentration decreased from 13.77 μg g−1 at 1-h post dosing to 0.39 μg g−1 at 240-h post dosing. Water FFC concentration decreased from a maximum of 1400 ng mL−1 at 1 day post-dosing to 847 ng mL−1 at 240 h post-dosing. There were no adverse effects noted on fish, feed consumption or biofilter function associated with FFC-medicated feed administration to tilapia.

Spatial and temporal variation in population genetic structure of wild Nile tilapia (Oreochromis niloticus across Africa

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Bezault Etienne

2011-12-01

Full Text Available Abstract Background Reconstructing the evolutionary history of a species is challenging. It often depends not only on the past biogeographic and climatic events but also the contemporary and ecological factors, such as current connectivity and habitat heterogeneity. In fact, these factors might interact with each other and shape the current species distribution. However, to what extent the current population genetic structure reflects the past and the contemporary factors is largely unknown. Here we investigated spatio-temporal genetic structures of Nile tilapia (Oreochromis niloticus populations, across their natural distribution in Africa. While its large biogeographic distribution can cause genetic differentiation at the paleo-biogeographic scales, its restricted dispersal capacity might induce a strong genetic structure at micro-geographic scales. Results Using nine microsatellite loci and 350 samples from ten natural populations, we found the highest genetic differentiation among the three ichthyofaunal provinces and regions (Ethiopian, Nilotic and Sudano-Sahelian (RST = 0.38 - 0.69. This result suggests the predominant effect of paleo-geographic events at macro-geographic scale. In addition, intermediate divergences were found between rivers and lakes within the regions, presumably reflecting relatively recent interruptions of gene flow between hydrographic basins (RST = 0.24 - 0.32. The lowest differentiations were observed among connected populations within a basin (RST = 0.015 in the Volta basin. Comparison of temporal sample series revealed subtle changes in the gene pools in a few generations (F = 0 - 0.053. The estimated effective population sizes were 23 - 143 and the estimated migration rate was moderate (m ~ 0.094 - 0.097 in the Volta populations. Conclusions This study revealed clear hierarchical patterns of the population genetic structuring of O. niloticus in Africa. The effects of paleo-geographic and climatic events were

Marine Science

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The local communities' eco- nomic activities involve fishing, seaweed farming and ..... and body composition of Nile tilapia (Oreochromis niloticus) fingerlings. ... King JM, Brown CA (2006) River Health Assessment. IUCN Water and Nature ...

Agro 13 No 3 Ready

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Moringa oleifera is an indigenous tree growing in Southwestern Nigeria for ... compounds in Moringa oleifera to freshwater fish, Oreochromis niloticus fingerlings. ..... (2008)''Effectiveness of Moringa oleiferaLam. seeds as natural coagulant in ...

Age and growth of dominant cichlids in Gbedikere Lake, Kogi Statr ...

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Sixty samples of the fish species comprising thirty Tilapia zilli and thirty Oreochromis niloticus were obtained from the Artisanal fishers from the common landing site along the lake. Age was determined from Bhattacharya's length frequency assortment method using where applicable the scale of fish and opercula bones.

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ABSTRACT. The current study explores information on fish diversity and fishing gears used in Tomas Dam. Danbatta, Kano State and Daberam Dam Daura, Katsina State. From the results 5 different species belonging to 3 families were found in Tomas dam, and these are; Tilapia zilli, Oreochromis niloticus.

miR-1338-5p Modulates Growth Hormone Secretion and Glucose Utilization by Regulating ghitm in Genetically Improved Farmed Tilapia (GIFT, Oreochromis niloticus).

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Qiang, Jun; Bao, Jing Wen; Li, Hong Xia; Chen, De Ju; He, Jie; Tao, Yi Fan; Xu, Pao

2017-01-01

MicroRNAs (miRNAs) are endogenous, non-coding small RNA molecules about 22 nt in length, which could regulate the expressions of target genes and participate in growth and development of organisms. Genetically improved farmed tilapia (GIFT, Oreochromis niloticus ) is an important economic freshwater species in China and the growth performance is one of the main breeding indicators. Growth hormone inducible transmembrane protein ( ghitm ) plays an important role in growth and development of both mammals and invertebrates; however, little studies have been reported on fish. Our previous experiments indicated that miR-1338-5p expression may be negatively correlated with ghitm expression. In this study, we firstly used qRT-PCR and northern blot to verify the expression of miR-1338-5p and ghitm , and determined the binding site of miR-1338-5p in the ghitm 3'-untranslated region (UTR) by luciferase reporter assay. Secondly, juveniles GIFT injected with miR-1338-5p antagomir were used to analyze the regulatory function of the miR-1338-5p- ghitm pair in vivo . The results showed that the ghitm 3'-UTR was complementary to the 5' 2-8-nt site of miR-1338-5p. Inhibition of miR-1338-5p promoted ghitm expression in the pituitary and liver of GIFT. ghitm could interfere in the growth hormone (Gh)-growth hormone receptor (Ghr)-insulin-like growth factor (Igf) signaling pathway by competing with the ghr1 for combination with Gh, and then reduce the growth of GIFT. Moreover, the reduction of Gh in serum may regulate insulin secretion and result in the increasing sugar and fat storage in serum and liver. Our results suggest that miR-1338-5p participates in the growth and development of GIFT through the regulation of ghitm , which provides theoretical support for the study of the fish growth mechanism.

Impact of using raw or fermented manure as fish feed on microbial quality of water and fish

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Nagham Elsaidy

2015-01-01

Full Text Available The microbial water and fish quality was assessed due to feeding of chicken manure (CM and fermented chicken manure (FCM to fish in ponds, using Nile tilapia (Oreochromis niloticus which were classified into 7 groups (G. Each group received different mixtures of CM or FCM with fish ration (FR, 0:100, 25:75, 50:50 and 100:0 (%CM or FCM:% FR. The obtained results revealed that total bacterial count (TBC and total coliform count (TCC were significantly high at P ⩽ 0.05 in CM than both FCM and fish ration (FR. Escherichia coli and Salmonella were isolated from CM but not from FCM or FR. Additionally, TBC and TCC were significantly high at P ⩽ 0.05 at water and fish samples raised at CM ponds followed by FCM ponds in comparison with FR. Both E. coli and Salmonella were isolated from water and fish raised in ponds receiving either CM or FCM with higher incidence in those with CM. However all water and fish samples examined were free from E-coli O157: H7. The obtained results, proved the influence of CM on water and fish quality and recommend the use of FCM as a bacteriologically safe fish pond fertilizer.

Effects of Lead+Selenium Interaction on Acetylcholinesterase Activity in Brain and Accumulation of Metal in Tissues of Oreochromis niloticus (L., 1758

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Gülsemin Şen

2017-06-01

Full Text Available The potential accumulation of lead in different tissues of Oreochromis niloticus and the effects of selenium in AChE inhibition caused by lead in brain were investigated. Juvenile O. niloticus samples were exposed to combination of 1 mg L-1 and 2 mg L-1 lead and 1mg L-1 lead+2mg L-1 selenium and 2mg L-1 lead+4mg L-1 selenium for 1, 7 and 15 days respectively. The accumulation of lead in gill, brain, liver and muscle tissues was analyzed by Inductively Coupled Plasma Mass Spectrometry (ICP-MS as well as brain acetylcholinesterase (AChE, E.C.3.1.1.7 enzyme activity was also analyzed by spectrophotometric method. No mortality was observed during lead exposure in relation to time period and exposed concentrations. Lead accumulation was occurred in all tissues in relation to time. Maximum lead accumulation occurred in brain tissue, followed by the liver, gills and muscle tissues in relation to time period. Selenium caused decrease accumulation of lead in tissues (all selenium mixtures in muscle tissue on the first day, 1mg L-1 Pb+2mg L-1 selenium in gill tissue on the seventh day, in liver tissue on the seventh day except 2mg L-1 Pb+4mg L-1 selenium mixtures at the end of each of all three test periods. Inhibition of AChE activity was caused by the highest concentration and by the short-term effect of lead. Such effect of lead was eliminated by selenium mixture. Lead and selenium mixture were resulted an increase in activity on 15th day at the highest concentration. Selenium led to decrease in the accumulation of lead in the tissues and caused to improvement in the loss of AChE activity.

Modulation of growth performance, immunological responses and disease resistance of juvenile Nile tilapia (Oreochromis niloticus (Linnaeus, 1758 by supplementing dietary inosine monophosphate

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Md. Abdul Kader

2018-05-01

Full Text Available This study was investigated to examine supplemental effects of dietary inosine monophosphate (IMP on growth performance, feed utilization, biochemical, hematological and immunological parameters of juvenile Nile tilapia Oreochromis niloticus. Disease resistance to experimental infection with Streptococcus agalactiae was also assessed. A semi-purified basal diet was supplemented with 0 (IMP0, Control, 1 (IMP1, 2 (IMP2, 4 (IMP4 and 8 (IMP8 g purified IMP kg−1 diet to formulate five experimental diets. Each diet was randomly allocated to triplicate groups of fish (0.59 g for 60 days. The results indicated that supplementation of IMP significantly (P  0.05. Among whole body proximate composition and somatic parameters, condition factor was significantly influenced by dietary supplementation of IMP. A wide variation in hematological parameters were observed and dietary supplementation increased the hematocrit content (P  0.05. Total serum protein (TSP, lysozyme activity (LA, superoxide dismutase activity (SOD and bactericidal activity (BA tended to increase with the supplementation of dietary IMP. TSP and SOD were significantly improved with ≥4 g kg−1 supplementation, while LA with 8 g kg−1 and BA with ≥1 g kg−1 supplementations. IMP supplemented groups showed higher (P > 0.05 cumulative survival compared to that of supplementation free control group. IMP supplemented diet groups also showed significantly higher BA in the post challenge test. Based on the overall performances, the results of the current study indicated that the inclusion of IMP in Nile tilapia diet can improve growth performance, feed utilization, haematological and immunological parameters; and disease resistance of juvenile Nile tilapia. Keywords: Nucleotides, Inosine monophosphate, Growth, Immunity, Disease resistance, Nile tilapia, Streptococcus agalactiae

Fauna parasitária de peixes oriundos de “pesque-pague” do município de Guariba, São Paulo, Brasil - DOI: 10.4025/actascibiolsci.v28i3.253 Parasitic fauna of cultivated fishes in fee fishing farm of Guariba, São Paulo State, Brazil - DOI: 10.4025/actascibiolsci.v28i3.253

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Julieta Rodini Engracia de Moraes

2007-11-01

Full Text Available Este trabalho descreve a ocorrência e a sazonalidade de parasitos em peixes de “pesque-pague” do município de Guariba, Estado de São Paulo, Brasil (21º15`22``S, 48º18`58``W e 595 m de altitude, durante o período de agosto de 2001 a julho de 2002. A presença de parasitos foi pesquisada em pacu Piaractus mesopotamicus (Characidae, carpa comum Cyprinus carpio (Cyprinidae, tilápia-do-Nilo Oreochromis niloticus (Cichlidae, híbrido tambacu (macho de P. mesopotamicus x fêmea de tambaqui-Colossoma macropomum e piraputanga Brycon hillari (Characidae. Os resultados demonstram que dos 100 peixes examinados, 15% estavam parasitados por pelo menos um dos seguintes parasitos: Trichodina sp.; helmintos monogenóides; copepoditos de Lernaea cyprinacea; L. cyprinacea adulta ou Dolops carvalhoi. Por ordem decrescente, o grau de suscetibilidade dos hospedeiros foi C. carpio, P. mesopotamicus, B. hillari, híbrido tambacu e O. niloticus. Por ordem decrescente, os parasitos encontrados foram helmintos monogenóides, Dolops carvalhoi, Trichodina sp., Lernaea cyprinacea adultas e suas formas jovens.This study describes the occurrence and the seasonality of parasites of cultivated fish from a fee fishing farm located in Guariba, São Paulo State, Brazil (21º15`22`` S, 48º18`58`` W and 595 m of altitude, from August, 2001 to July, 2002. The presence of parasites was researched in pacu Piaractus mesopotamicus (Characidae, common carp Cyprinus carpio (Cyprinidae, nile-tilapia Oreochromis niloticus (Cichlidae, tambacu hybrid (male of P. mesopotamicus x female of tambaqui-Colossoma macropomum and piraputanga Brycon hillari (Characidae. Results demonstrate that out of 100 fish examined, 15% were sponged for at least one of the following parasites: Trichodina sp.; monogenean helminths; copepodits of Lernaea cyprinacea; adults of L. cyprinacea; or Dolops carvalhoi. In decreasing order, the susceptibility degree of the hosts was C. carpio, P. mesopotamicus, B

IGF-1 induces SOCS-2 but not SOCS-1 and SOCS-3 transcription in juvenile Nile tilapia (Oreochromis niloticus).

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Liu, Cai-Zhi; Luo, Yuan; Limbu, Samwel Mchele; Chen, Li-Qiao; Du, Zhen-Yu

2018-05-20

Insulin-like growth factor-1 (IGF-1) plays a crucial role in regulating growth in vertebrates whereas suppressors of cytokine signaling (SOCS) act as feedback inhibitors of the GH/IGF-1 axis. Although SOCS-2 binds the IGF-1 receptor and inhibits IGF-1-induced STAT3 activation, presently there is no clear evidence as to whether IGF-1 could induce SOCS gene expression. The current study aimed to determine whether IGF-1 could induce the transcription of SOCS in juvenile Nile tilapia ( Oreochromis niloticus ). We show that there is a common positive relationship between the mRNA expression of IGF-I and SOCS-2 under different nutritional statuses and stimulants, but not the mRNA expression of SOCS-1 and SOCS-3 Furthermore, rhIGF-1 treatment and transcriptional activity assay confirmed the hypothesis that IGF-1 could induce SOCS-2 expression, whereas it had no effect or even decreased the expression of SOCS-1 and SOCS-3 Overall, we obtained evidence that the transcription of SOCS-2, but not SOCS-1 or SOCS-3, could be induced by IGF signaling, suggesting that SOCS-2 serves as a feedback suppressor of the IGF-1 axis in juvenile Nile tilapia. © 2018. Published by The Company of Biologists Ltd.

Effects of tartary buckwheat polysaccharide combined with nisin edible coating on the storage quality of tilapia (Oreochromis niloticus) fillets.

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Wang, Fengping; Zhang, Huijun; Jin, Wengang; Li, Lirong

2018-06-01

To investigate the effect of tartary buckwheat polysaccharide (TBP) combined with nisin edible coatings on the preservation of tilapia (Oreochromis niloticus) fillets, fillets were dip treated with different concentrations of TBP (5, 10 and 15 g kg -1 ) combined with nisin and stored at 4 °C for 12 days. The pH values, thiobarbituric acid contents, total volatile base nitrogen (TVB-N) content, total viable count (TVC), surface colors, textures and sensory properties of the tilapia fillets at storage were all periodically investigated. TBP combined with nisin-treated groups significantly improved the bacteriological, physicochemical, and sensory characteristics of the tilapia fillets to a greater extent compared to the control group and presented better quality preservation effects than nisin coating alone. Based on the limits of the TVB-N, TVC and sensory scores, the shelf life of the control tilapia fillets was 4 days, whereas that for nisin with TBP-coated fillets was 8-10 days. Edible coatings made from TBP combined with nisin are suitable for maintaining qualities and enhancing the shelf lives of tilapia fillets stored at 4 °C. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Feeding selectivity of wild and pond-cultured Nile tilapia ...

African Journals Online (AJOL)

A comparison of feeding selectivity of wild and pond-cultured Nile tilapia Oreochromis niloticus was conducted in 2008. Water and fish samples were collected in Shirati Bay, Lake Victoria, and from fish ponds in Tarime district using a La Motte water sampler and seine nets, respectively. Cyanophytes were abundant and ...

Blue tilapia (Oreochromis aureus) predation on fishes in the Muddy River system, Clark County, Nevada

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Scoppettone, G.G.; Salgado, J.A.; Nielsen, M.B.

2005-01-01

Blue tilapia (Oreochromis aureus), native to North Africa and the Middle East (Courtenay and Robins 1973, Fuller et al. 1999), has been introduced around the world as a human food source, for vegetation control, and as a game fish (Costa-Pierce and Riedel 2000). Blue tilapia has been particularly successful in establishing and spreading in North American waters where it has been reported to change fish community structure and cause native fish decline (Courtenay and Robins 1973, Fuller et al. 1999). Because of these detrimental effects, it is now generally considered an unwelcome introduction into North American waters (Dill and Cordone 1997, Fuller et al. 1999).

Irradiated Palm Oil Waste (Sludge) As Feed Supplement For Nila Gift Fish (Oreochromis niloticus)

International Nuclear Information System (INIS)

MU, Jenny; PM, Adria

2002-01-01

The objective of the experiment was to study the fish weight development after being fed with irradiated palm oil waste pellet. Irradiated Palm oil waste pellet was produced from palm oil waste (sludge) with some additional materials, i.e. rice bran, fish powder, soybean powder, tapioca powder. The mixture was then irradiated with a dose of 4 kGy to decontaminate pathogen microbe and other contaminant microbes, the experiment have been carried out in 4 treatments. Treatment A was male fish which was being fed with irradiated sludge palm oil waste pellet and commercial pelletized feed (2:1), treatment C was female with the same feed as A, treatment B was male fish feed with commercial pelletized, treatment D was female fish with the same feed as B. Each treatment was placed in a pond. The feed with the amount of 3% of total body weight was given to the fishes 2 times per day. The result of this experiment showed that the male fish weight receiving treatment A and B were 195.37 g and 175.12 g. The female fish weight at treatments C and D were 170.28 g and 160.15 g, respectively. Data obtained from this experiment showed that the treatment of irradiated sludge palm oil waste pellet and commercial pelletized (2:1) were more efficient as fish feeding compared to commercial pellets

Efeito da vitamina C sobre o hematócrito e glicemia de alevinos de tilápia-do-nilo (Oreochromis niloticus em transporte simulado Effect of vitamin C over the haematocrit and glycemia of nile tilapia (Oreochromis niloticus alevins in simulated transport

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D. Okamura

2007-08-01

Full Text Available Avaliou-se o efeito do ascorbato sobre o hematócrito e glicemia em alevinos de tilápia nilótica (Oreochromis niloticus submetidos à simulação de práticas relacionadas ao transporte. Foram utilizadas três dietas experimentais com diferentes níveis de vitamina C (16, 500 e 1000mg de vitamina C/kg, fornecidas durante os 14 dias anteriores à simulação do transporte que se estendeu por 14 horas. O tratamento que continha 16mg de vitamina C/kg foi o que apresentou a glicemia mais elevada logo após a simulação, 108,5mg/dl imediatamente após a simulação e 91mg/dl 12 horas após a simulação. A concentração de 1000mg de vitamina C/kg foi a mais eficiente no controle do aumento da glicemia, 94,6mg/dl imediatamente após a simulação e 74,4mg/dl 12 horas após a simulação. Para a concentração de 500mg de vitamina C/kg foram observados os níveis de 91,4mg/dl imediatamente após a simulação e 103,8mg/dl 12 horas após a simulação. Os valores do hematócrito não apresentaram variação significativa (P>0,05. A suplementação com 1000mg de vitamina C/kg por 14 dias anteriores ao transporte pode ser utilizada de forma profilática em alevinos de tilápia nilótica para amenizar o aumento da glicemia relacionado ao estresse.The effects of ascorbate on the haematocrit and blood glucose level were evaluated in Nile tilapia alevins (Oreochromis niloticus submitted to a transport simulation. Three experimental diets with different levels of vitamin C (16, 500 and 1000mg/kg were given for 14 days before the simulation of the transport. The treatment containing 16mg of vitamin C showed the highest level of glucose after the simulation (108.5mg/dl immediately after the transport and 91mg/dl 12 hours after the transport. The vitamin C concentration of 1000mg/kg was the most efficient treatment to control glycemia increases (94.6mg/dl immediately after the simulation and 74.4mg/dl 12 hour after simulation. In the 500mg/kg treatment, the

Hematological and morphometric blood value of four cultured species of economically important tropical foodfish

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Genoefa Amália Dal'Bó

Full Text Available The use and validation of fish health monitoring tools have become increasingly evident due to aquaculture expansion. This study investigated the hematology and blood morphometrics of Piaractus mesopotamicus, Brycon orbignyanus, Oreochromis niloticus and Rhamdia quelen. The fish were kept for 30 days in 300-liter aquariums, after which they were anesthetized with benzocaine and blood was collected from caudal vessels. In comparison to other species, B. orbignyanus presented the highest hematocrit (Ht, RBC averages and Mean Corpuscular Volume (MCV with a particular range of data. B. orbignyanus presented lower Ht, Hb, RBC averages and values, and Mean Corpuscular Hemoglobin Concentration (MCHC. Oreochromis niloticus presented lower Ht, Hb, RBC averages and values, and Mean Corpuscular Hemoglobin Concentration (MCHC. Rhamdia quelen and O. niloticus presented higher variation of White Blood Cells (WBC, neutrophils (Nf, lymphocytes (Lf, monocytes (Mf and thrombocytes (Trb. Data of large axes (LA, minor axes (MA, surface (SF and volume (VL are in the same variance range. This study has demonstrated that hematological variances can occur between animals of different species as well as of the same species.

VAKSINASI IKAN TILAPIA (Oreochromis niloticus MENGGUNAKAN VAKSIN MONOVALEN DAN BIVALEN UNTUK PENCEGAHAN PENYAKIT MOTILE AEROMONAS SEPTICEMIA DAN STREPTOCOCCOSIS

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Desy Sugiani

2013-08-01

Full Text Available Peningkatan respon antibodi pascavaksinasi dengan antigen tunggal dan campuran dari bakterin Aeromonas hydrophila and Streptococcus agalactiae diharapkan dapat meningkatkan daya tahan ikan tilapia (Oreochromis niloticus terhadap penyakit Motile Aeromonas Septicemia/MAS dan Streptococcosis. Sediaan vaksin disiapkan dengan metode pembuatan dan formula yang berbeda, proses inaktifasi dilakukan dengan menambahkan 3% Neutral Buffer Formalin (NBF 10% pada biakan bakteri dalam media tumbuh BHI dan TSB. Vaksinasi diberikan melalui injeksi intraperitoneal dengan sediaan vaksin monovalen A. hydrophila, monovalen S. agalactiae, dan bivalen A. hydrophila + S. agalactiae (Sel utuh, produk ektraselular/ECP, crude supernatan, campuran sel utuh + ECP, dan broth. Uji tantang dilakukan menggunakan dosis LD50 infeksi tunggal maupun ko-infeksi dari bakteri A. hydrophila dan S. agalactiae. Efektivitas dan keampuhan vaksin tersebut dihitung berdasarkan nilai RPS (Relative Percent Survival dan hasil respon hematologi. Titer antibodi dapat terdeteksi setelah satu minggu pemeliharaan pasca vaksinasi. Nilai titer antar perlakuan vaksin bivalen berbeda nyata (P<0.05 dengan vaksin monovalen dan kontrol. Nilai RPS vaksin bivalen (campuran sel utuh + ECP mencapai 100 untuk uji tantang dengan A. hydrophila dan 56,7 pada uji tantang ko-infeksi. Vaksin monovalen A. hydrophila maupun S. agalactiae hanya mampu memproteksi terhadap bakteri homolog, tidak terjadi proteksi silang di antara keduanya.

Parâmetros hematológicos e bioquímicos da tilápia-do-Nilo (Oreochromis niloticus L. sob estresse por exposição ao ar Hematological parameters of Nile Tilapia (Oreochromis niloticus L. under air exposure stress

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Roberta Dias da Silva

2012-12-01

Full Text Available No presente trabalho avaliaram-se os parâmetros hematológicos e bioquímicos de exemplares adultos de tilápias (Oreochromis niloticus sob a influência do fator estresse fisiológico em animais submetidos à exposição ao ar durante a engorda em sistema raceway. Foram analisados o eritrograma, teor de hemoglobina, volume globular, o volume corpuscular médio (VCM, a hemoglobina corpuscular média (HCM, a concentração de hemoglobina corpuscular média (CHCM, o leucograma, contagem diferencial de leucócitos, o plaquetograma, a glicose, a proteína total, o colesterol, o triglicerídeo e os eletrólitos (cálcio, cloretos, sódio e potássio. Os resultados revelaram que houve uma homogeneidade de distribuição para hemácias, volume globular, hemoglobina, índices hemantimétricos, proteína total, glicose, colesterol, e íons séricos, indicados pelos valores relativamente baixos do coeficiente de variação. Houve correlação positiva somente para leucócitos totais, células de defesa orgânica (neutrófilos e linfócitos, glicose, colesterol, sódio e cálcio. Quanto ao leucograma, à medida que os animais foram expostos ao ar, o número de leucócitos diminuiu gradativamente (leucopenia, ocorrendo simultaneamente neutrofilia e linfopenia. O índice glicêmico constituiu um bom indicador de estresse fisiológico, devido à hiperglicemia (82,0±20,88mg/dL demonstrada nos tratamentos. A exposição ao ar constituiu um fator de desequilíbrio na homeostase iônica, e na síntese de colesterol endógeno. Entretanto, o tempo de recuperação não ocasionou a completa reabilitação fisiológica frente ao desafio imposto.The present study evaluated the hematological and biochemical parameters of adult tilapia (Oreochromis niloticus under the influence of the physiological stress factor in animals submitted to air exposure during fattening in raceway system. Blood cell count, hemoglobin, hematocrit, mean corpuscular volume (MCV, mean

First evidence of microplastics in the African Great Lakes

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Biginagwa, Fares John; Mayoma, Bahati Sosthenes; Shashoua, Yvonne

2016-01-01

-FTIR) spectroscopy. A variety of polymer types were identified with likely sources being urban waste and consumer use. Although further research is required to fully assess the impact of plastic pollution in this region, our study is the first to report the presence of microplastics in Africa's Great Lakes...... on the southern shore of Lake Victoria. The gastrointestinal tracts of locally fished Nile perch (Lates niloticus) and Nile tilapia (Oreochromis niloticus) were examined for plastics. Plastics were confirmed in 20% of fish from each species by Attenuated Total Reflectance Fourier Transform Infrared (ATR...

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. Copyright © 2015 Elsevier Ltd. All rights reserved.

Avaliação de rações fareladas e micropeletizadas para larvas de tilápia do Nilo (Oreochromis niloticus - desempenho e efetividade da reversão sexual - DOI: 10.4025/actascianimsci.v26i2.1865 Crumble and meal ration evaluate to Nile tilapia (Oreochromis niloticus larvae during sexual reversion phase - DOI: 10.4025/actascianimsci.v26i2.1865

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Fábio Meurer

2004-04-01

Full Text Available O objetivo do presente trabalho foi avaliar o efeito do processamento da ração de larvas de Oreochromis niloticus L. utilizada durante o processo de reversão sexual, sobre a sobrevivência, desempenho e proporção sexual. O período experimental foi de 30 dias, o delineamento foi inteiramente casualizado com 3 tratamentos e 6 repetições, considerando uma unidade experimental um aquário de 12L, contendo 20 larvas. No primeiro tratamento, utilizou-se ração farelada por 30 dias; no segundo, ração farelada durante os primeiros 10 dias e micropeletizada durante os 20 dias restantes; no terceiro, ração farelada durante os primeiros 20 dias e micropeletizada durante os 10 dias restantes. Ao final do experimento, os parâmetros de peso, comprimento, sobrevivência e proporção sexual foram submetidos à análise de variância a 5% de significância. Os parâmetros avaliados não apresentaram diferença significativa entre os tratamentos. A utilização da ração farelada ou micropeletizada pode ser feita sem prejuízo do desempenho, sobrevivência ou masculinização da tilápia nesta fase.The objective from this work was evaluate the effect of ration processing to Oreochromis niloticus L. larvae, on survival, performance and sexual reversal efficiency in sex revert phase. The experimental period were 30 days, and it was utilized a completely randomized design with tree treatments and six replications. An experimental unit was consist of 12L aquarium, with 20 larvae. The first treatment was consist of only meal ration utilization; the second treatment utilized a meal ration until 10th day and after crumble ration; and the third treatment utilized meal ration until 20th day and after crumble ration. At the end of the experiment, there were analysed weight, lenght, mortality and sex reversal. The data were submitted to analysis of variance and didn’t present differences (P>0.05 among treatments. The meal ration can be utilized without

Composicao quimica, perfil de acidos graxos e quantificacao dos acidos ƒ¿-linolenico, eicosapentaenoico e docosahexaenoico em visceras de tilapias (Oreochromis niloticus = Percentual composition, fatty acids and quantification of the LNA (Alfa-Linolenic, EPA (Eicosapentaenoic and DHA (Docosahexaenoic acids in visceras of Nile Tilapia (Oreochromis niloticus

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Nilson Evelázio de Souza

2005-01-01

Full Text Available Foi avaliada a composição química de vísceras de tilápias (Oreochromis niloticus criadas em cativeiro Os teores de umidade, cinza, proteína bruta e lipídios totais foram de 64,4%; 1,3%; 6,3% e 18,0%, respectivamente, caracterizando alta concentração de lipídiostotais em relação a outros resíduos de peixes. Foram identificados 49 ácidos graxos, sendo majoritários os ácidos: oléico, (32,8%, seguido do palmítico, (19,9% e linoléico, (18,2%. As razões entre n-6/n-3 e ácidos poliinsaturados/saturados foram de 5,5 e 0,9, respectivamente. As quantificações dos ácidos graxos alfa-linolênico, eicosapentaenóico e docosahexaenóico, em mg/g de lipídios totais, foram de 10,4, 1,4 e 9,3, respectivamente. O elevado teor de lipídios totais das vísceras contribuiu significativamente para as quantidadesde ácidos graxos n-3. Todos os parâmetros analisados foram satisfatórios sob o ponto de vista nutricional e neste sentido as vísceras de tilápias poderão ser utilizadaa para alimentar peixes ou outros animais.The chemical composition was evaluated in visceras of tilapias raised in captivity. The moisture, ash, crude protein and total lipids contents were 64.4%; 1.3%; 6.3% and 18.0%, respectively, characterizing high total lipids concentration in relation other residues of fish. Forty nine fatty acids were detected, the major fatty acids were oleic (32.8%, palmitic (19.9% and linoleic-1 (18.2% and oleic (9.4%. The ratio n-6/n-3 and polyunsaturated/saturated fatty acids, showed the values 5.5 and 0.9, respectively. The quantifications of alfa-linolenic, eicosapentaenoic and docosahexaenoic acids (in mg/g of total lipids, were 10.4, 1.4 and 0.3, respectively. The higher contents of total lipids in visceras contributed significantly for amounts of n-3 fatty acids. All the parameters analyzed were shown nutritional value satisfactory in this sense visceras of tilapias can be used in the feed of fish and other animal.

Effects of dietary resveratrol supplementation on hepatic and serum pro-/anti-inflammatory activity in juvenile GIFT tilapia, Oreochromis niloticus.

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Zheng, Yao; Zhao, Zhixiang; Wu, Wei; Song, Chao; Meng, Shunlong; Fan, Limin; Bing, Xuwen; Chen, Jiazhang

2017-08-01

Dietary resveratrol (RES) supplementation may have some pharmacological effects including anti-inflammation. Previous studies have shown that Kupffer cell activation and apoptosis induction increases the transcription of pro- and anti-inflammatory cytokines. The main purpose of this study was to investigate the pro- and anti-inflammatory activities of 0.1 or 0.3 g/kg RES as a dietary supplement in juvenile freshwater tilapia (Oreochromis niloticus). The results showed that hepatic and serum immunoglobulin M (IgM) significantly decreased and increased while anti- and pro-inflammatory cytokines significantly increased and decreased, respectively, in the RES-treated groups. The expression of serum and hepatic IgM and anti-inflammatory cytokines [interleukin (IL)-10] and its inverse inhibitor interferon (IFN)-γ significantly increased while pro-inflammatory cytokine transcription significantly decreased. Hematoxylin-eosin staining and scanning electron microscopy revealed intestinal deformation, irregular goblet cells, and apoptotic cells in the 0.3 g/kg RES groups. RES (0.3 g/kg) also induced necrosis, apoptosis, reduction in Kupffer cell number, compressed sinusoids, and deformation of epidermal cells in the liver of the treated groups. In conclusion, the results of the present study show that high doses of RES were absorbed in the gut and then damaged the liver and intestinal tissue. Copyright © 2017. Published by Elsevier Ltd.

Optimum dietary protein requirement of genetically male tilapia ...

African Journals Online (AJOL)

The study was conducted to investigate the optimum dietary protein level needed for growing genetically male tilapia, Oreochromis niloticus. Diets containing crude protein levels 40, 42.5, 45, 47.5 and 50% were formulated and tried in triplicates. Test diets were fed to 20 fish/1m3 floating hapa at 5% of fish body weight daily ...

miR-122 promotes hepatic antioxidant defense of genetically improved farmed tilapia (GIFT, Oreochromis niloticus) exposed to cadmium by directly targeting a metallothionein gene.

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Qiang, Jun; Tao, Yi-Fan; He, Jie; Xu, Pao; Bao, Jin-Wen; Sun, Yi-Lan

2017-01-01

MicroRNAs (miRNAs) are small, non-coding RNAs that regulate target gene expression by binding to the 3'untranslated region (3'UTR) of the target mRNA. MiRNAs regulate a large variety of genes, including those involved in liver homeostasis and energy metabolism. Down-regulated levels of hepatic miR-122 were found in genetically improved farmed tilapia (GIFT, Oreochromis niloticus) exposed to cadmium (Cd) stress. Here, we report for the first time that reduction of miR-122 post-transcriptionally increased metallothionein (MT) mRNA levels by binding to its 3'UTR, as shown by a 3' UTR luciferase reporter assay. The expression levels of miR-122 were negatively related to MT levels in GIFT under Cd stress. We performed in vivo functional analysis of miR-122 by injecting the fish with a miR-122 antagomir. Inhibition of miR-122 levels in GIFT liver caused a significant increase in MT expression, affected white blood cell and red blood cell counts, and serum alanine and aspartate aminotransferase activities, and glucose levels, all of which may help to relieve Cd stress-related liver stress. miR-122 silencing modulated oxidative stress and stimulated the activity of antioxidant enzymes. Our findings indicate that miR-122 regulated MT levels by binding to the 3'UTR of MT mRNA, and this interaction affected Cd stress induction and the resistance response in GIFT. We concluded that miR-122 plays an important role in regulating the stress response in GIFT liver. Our findings may contribute to understanding the mechanisms of miRNA-mediated gene regulation in tilapia in response to environmental stresses. Copyright © 2016 Elsevier B.V. All rights reserved.

MERCURY (Hg CONTENT OF MEAT TILAPIA FISH (Oreochromis niloticus WERE CULTIVATED IN PALANGKA RAYA CITY

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Ciptadi

2015-11-01

Full Text Available Tilapia fish as Palangkarayan food are mostly cultivated in the river which exposed by mercury. To get information whether the fish have been contaminated by mercury, the mercury determination of tilapia fish meat cultivated in Kahayan river was carried out. The fish were analyzed based on age and the cultivation environment that are fishes cages in Kahayan river and isolated pond from streams of Kahayan river are also studied. The concentration of mercury in the flesh of tilapia with 5-7 months, kept in cages used to identify the content of mercury in fish tilapia cages in Kahayan river. The concentration of mercury in the flesh of tilapia reared in ponds aims to compare the mercury content in the tilapia in ponds the same age were used as comparison. The level of mercury in the samples was measured using a Mercury Analyzer. Data concentration of mercury in the flesh of tilapia were analyzed using analysis of variance (ANOVA: single factor with a significance level (α of 5%. The results showed that tilapia fish meat from the cages in the Kahayan river with age of 5-7 months contain mercury as much as 0.0145 ± 0.0005 ppm to 0.017 ± 0.001 ppm, which were lower than the maximum limit of mercury contamination in fish and processed products regulated by ISO 7387 in 2009 of 0.5 ppm. The the analysis of variance showed that the mercury content in tilapia fish meat was different by age and place of cultivation. The content of mercury in the tilapia fish meat increase with the increase of their age. The mercury content in tilapia fish cultivated in the isolated pond lower than that of in the tilapia fish meat cultivated in cages of 0.0115 ± 0.0005 ppm

Effects of exposure to Streptococcus iniae on microRNA expression in the head kidney of genetically improved farmed tilapia (Oreochromis niloticus).

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Qiang, Jun; Tao, Fanyi; He, Jie; Sun, Lanyi; Xu, Pao; Bao, Wenjin

2017-02-20

Genetically improved farmed tilapia (GIFT, Oreochromis niloticus) are susceptible to infection by Streptococcus iniae when maintained in modern intensive culture systems. GIFT are commercially important fishes that are cultured widely in southern China. The role of microRNAs (miRNAs) in the regulatory response of GIFT to S. iniae infection has been underestimated and has not yet been well studied. Head kidney has an important immune function in teleost fishes. The main aim of this study was to determine the possible function of miRNAs in head kidney of S. iniae-infected GIFT. MiRNAs are small, non-coding RNAs that regulate gene expression by binding to the 3'-untranslated regions of their target mRNAs. MiRNAs are known to regulate immune-regulated signaling and inflammatory response pathways. High-throughput deep sequencing of two libraries (control group [CO] and infected group [IN]) of RNA extracted from GIFT head kidney tissues generated 12,089,630 (CO) and 12,624,975 (IN) clean reads. Bioinformatics analysis identified 1736 and 1729 conserved miRNAs and 164 and 165 novel miRNAs in the CO and IN libraries, respectively. Three miRNAs (miR-310-3p, miR-92, and miR-127) were found to be up-regulated and four miRNAs (miR-92d-3p, miR-375-5p, miR-146-3p, and miR-694) were found to be down-regulated in the S. iniae-infected GIFT. The expressions of these miRNAs were verified by quantitative real-time PCR. RNAhybrid and TargetScan were used to identify complementary miRNA and mRNA target sites, and the Gene Ontology and Kyoto Encyclopedia of Genes and Genomes databases were used to annotate and predict potential downstream regulation of biological pathways. Seven target genes, which encode immune-related proteins (complement C3, cytidine deaminase, regulator of G-protein Rgs22, mitogen-activated protein kinase Mapk1, metabotropic glutamate receptorm GluR8, calcium-sensing receptor CaSR, and microtubule-associated protein Map1S) were predicted to play crucial roles in the

Sperm quality analysis in XX, XY and YY males of the Nile tilapia (Oreochromis niloticus).

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Gennotte, V; François, E; Rougeot, C; Ponthier, J; Deleuze, S; Mélard, C

2012-07-01

In Nile tilapia (Oreochromis niloticus), individuals with atypical sexual genotype are commonly used in farming (use of YY males to produce all-male offspring), but they also constitute major tools to study sex determinism mechanisms. In other species, sexual genotype and sex reversal procedures affect different aspects of biology, such as growth, behavior and reproductive success. The aim of this study was to assess the influence of sexual genotype on sperm quality in Nile tilapia. Milt characteristics were compared in XX (sex-reversed), XY and YY males in terms of gonadosomatic index, sperm count, sperm motility and duration of sperm motility. Sperm motility was measured by computer-assisted sperm analysis (CASA) quantifying several parameters: total motility, progressive motility, curvilinear velocity, straight line velocity, average path velocity and linearity. None of the sperm traits measured significantly differed between the three genotypes. Mean values of gonadosomatic index, sperm concentration and sperm motility duration of XX, XY and YY males, respectively ranged from 0.92 to 1.33%, from 1.69 to 2.22 ×10(9) cells mL(-1) and from 18'04″ to 27'32″. Mean values of total motility and curvilinear velocity 1 min after sperm activation, respectively ranged from 53 to 58% and from 71 to 76 μm s(-1) for the three genotypes. After 3 min of activity, all the sperm motility and velocity parameters dropped by half and continued to slowly decrease thereafter. Seven min after activation, only 9 to 13% of spermatozoa were still progressive. Our results prove that neither sexual genotype nor hormonal sex reversal treatments affect sperm quality in male Nile tilapias with atypical sexual genotype. Copyright © 2012 Elsevier Inc. All rights reserved.

Masculinização da tilápia do Nilo, Oreochromis niloticus, utilizando diferentes rações e diferentes doses de 17 a-metiltestosterona Masculinization of Nile tilapia, Oreochromis niloticus, using different diets and different doses of 17 a-methyltestosterone

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Cleide Schmidt Romeiro Mainardes-Pinto

2000-06-01

Full Text Available Os objetivos deste estudo foram comparar a eficiência de duas rações 1 (NUTRAVIT e 2 (IP, ambas com 40% de proteína bruta, contendo o andrógeno sintético 17 a-metiltestosterona (MT, e analisar a dosagem mais efetiva desse hormônio na reversão sexual da Tilápia do Nilo, Oreochromis niloticus, por intermédio da análise histológica das gonadas e da sexagem dos exemplares. Foram utilizadas 9600 larvas de tilápia do Nilo, com 7 dias de vida, recebendo os seguintes tratamentos, por um período de 45 dias: A - 30 mg MT/kg de ração 1; B - 60 mg MT/kg de ração 1; C - 30 mg MT/kg ração 2; D - 60 mg MT/kg ração 2 e dois grupos controle: E e F, rações 1 e 2, respectivamente, sem hormônio. Os resultados dos testes qui-quadrado das freqüências de indivíduos machos e fêmeas analisados histológica e macroscopicamente mostram que o número de machos obtidos nos tratamentos A, B, C e D foi maior que o dos grupos controle e a dosagem de 60 mg MT/kg de ração, nas rações 1 e 2, foi mais eficiente, resultando em 98% de machos. Entre as rações, o tratamento com a ração 1 apresentou o melhor resultado, para a dosagem de 30 mg MT/ kg de ração, não havendo, pois, diferença entre rações para a dose de 60 mg MT/kg de ração.The objectives of the present study were to compare the efficiency of two diets: 1 (NUTRAVIT and 2 (IP, both with 40% of crude protein, containing the synthetic androgen hormone 17 a-methyltestosterone (MT and to analyze the most effective dose of this hormone on the sex reversal of Nile tilapia Oreochromis niloticus, throughout histological analysis of the gonads and sex determination of the samples. A total of 9600 Nile tilapia fries with seven days posthatching received the following treatments, per 45 days period: A- 30 mg MT/kg diet 1; B- 60 mg MT/kg diet 1; C- 30 mg MT/kg diet 2; D- 60 mg MT/kg diet 2 and two control groups, E and F with diets 1 and 2 hormone free, respectively. The results of chi

Organochlorine Pesticides (OCPs) in Sediment and Fish of Two Tropical Water Bodies Under Different Land Use.

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Hinojosa-Garro, Demián; Burgos Chan, Adriana M; Rendón-von Osten, Jaime

2016-07-01

In this study we quantified and compared bioaccumulated OCPs in target fish species Cichlasoma urophthalmus (Mayan cichlid) and Oreochromis niloticus (Nile tilapia) and sediment in two lentic systems neighboring areas with different land use (Xnoha = agricultural/Mocu = nature reserve). Fish at both sites showed the same number of pesticide compounds (17) while in sediment were 17 and 20, respectively. ∑chlordane concentrations were significantly higher in Xnoha in both fish and sediment (1.0 and 0.17 µg/g, respectively). Here higher concentrations of o,p'DDT were found in fish than in sediments, this was similarly demonstrated in Mocu but to a lesser extent. The proportion of endosulfan sulfate was lower in Xnoha (<20 %) than in Mocu (<50 %) compared to the original product. Detected concentrations of ∑DDT and chlordane exceed international permissible limits. Results indicate that OCPs were present in both aquatic systems regardless of the differences in land use.

The effects of various preservation methods on fatty acid content of ...

African Journals Online (AJOL)

The effect of various preservation methods on fatty acid content of African catfish, (Clarias gariepinus) and Nile tilapia (Oreochromis niloticus) was investigated. Fresh fish samples were obtained from swimming pool end (Gamji Gate) of River Rino, Kaduna. Preservation methods investigated were: straight smoking (SS), ...

Histopathology of Tilapia tissues harbouring Clinostomum tilapiae ...

African Journals Online (AJOL)

Tissues obtained from infected Oreochromis niloticus were processed sectioned and stained with haemotoxylin and eosin. Good sections were selected, studied and photographed. The histopathology revealed a proliferation of eosinophiles at the secondary lamellar of the gills. The site of attachment on the fish skin ...

Benthic freshwater nematode community dynamics under conditions ...

African Journals Online (AJOL)

Studies of the influence of fish aquaculture on benthic freshwater nematode assemblages are scarce, but could provide a way of gauging environmental effects. The abundance and diversity of nematode assemblages in response to Oreochromis niloticus aquaculture were investigated in Kafr El-Sheikh Governorate, Egypt, ...

Biometric indices and size at first sexual maturity of eight alien fish species from Bangladesh

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Md. Yeamin Hossain

2016-09-01

Full Text Available The biometric indices and size at first sexual maturity of eight alien fish species from several water bodies in Bangladesh were studied for the first time. A total of 273 individuals of eight alien fish species (Barbonymus gonionotus, Clarias gariepinus, Ctenopharyngodon idella, Cyprinus carpio, Hypophthalmichthys molitrix, H. nobilis, Oreochromis niloticus and Pangasianodon hypophthalmus were collected using traditional fishing gears from June 2014 to May 2015. Among the four condition factors (Allometric condition factor, Fulton’s condition factor, Relative condition factor, and Relative weight studied, Fulton’s condition factor was the best for assessing the well-being of these alien species in their natural habitat, based on the relationships of condition factors with body weight and total length. The calculated form factor was 0.0270 for B. gonionotus, 0.0077 for C. gariepinus, 0.0119 for C. idella, 0.0194 for C. carpio, 0.0101 for H. molitrix, 0.0092 for H. nobilis, 0.0158 for O. niloticus and 0.0105 for P. hypophthalmus. The size at first sexual maturity was estimated in TL as 12.30 cm for B. gonionotus, 25.53 cm for C. gariepinus, 32.80 cm for C. idella, 18.22 cm for C. carpio, 23.92 cm for H. molitrix, 30.18 cm for H. nobilis, 21.78 cm for O. niloticus, and 21.32 cm for P. hypophthalmus. The present study also calculates form factor and first sexual maturity of these alien species from different water-bodies world over. The findings of this study can be very helpful for sustainable management of these alien species in Bangladesh and similar ecosystems.

Monitoring of heavy metals in marine and freshwater fishes and nutritional evaluation of fish consumption

International Nuclear Information System (INIS)

Rina Mulyaningsih

2014-01-01

Fish is a food source of minerals. Uptake of heavy metals in fish could come from water, sediment and fish feed. Monitoring of minerals content and contaminants in fish has been carried out to evaluate nutrition and food safety, using neutron activation analysis techniques. Marine fish species that being analyzed are Kembung (Rastrelliger faughni), mackerel (Acanthocybium solandri), Tuna (Authis thazard) and freshwater fishes are Bawal (Colossoma macropomum), Nila (Oreochromis niloticus), Mas (Cyprinus carpio), sampled from 6 markets in North Jakarta. Monitoring results indicate that the essential minerals contained in fish are Fe, K, Na, Zn, Ca, Mg, and Se. Se and Ca concentrations in marine fish are higher than in freshwater fish. The concentration of other essential elements varies depending on the type of fish. The concentration of arsenic in marine fish is 3 times higher than that of freshwater fish; Hg and Cr content in all fish species were observed. From the evaluation of the adequacy of nutrition, with assuming a consumption of 86.68 g fish/day, for men aged 19 - 30 years, and referring to data from the Institute of Medicine USA, the Ca intake : 2.5 - 6.3; Cl : 1.5 - 3.3; Fe : 11.5 - 26.9; Na : 1.5 - 4.1; K : 3.4 - 6.7 and Zn 3.9 - 7.2% of the recommended value. Cr intake exceeds the recommended value, while As and Hg is not recommended in the food. In fact these metals contained in the studied fish, but the concentration is still below the value of standards issued by BPOM. (author)

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

International Nuclear Information System (INIS)

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 -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 62.6±9.8% compared to the

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

Storage of vacuum-packaged smoked bologna sausage prepared from Nile tilapia

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Dayse Aline Ferreira Silva Bartolomeu

2014-02-01

Full Text Available Changes in smoked bologna sausage manufactured with Niletilapia (Oreochromis niloticus, and wheat fibers in refrigerated storage (6 ± 2°C during 30 days were evaluated. Minced fish (MF obtained from waste (parings from the filleting fish operations of Nile tilapia (Oreochromis niloticus was used as raw material. In this experiment, were determined Staphylococcus count, the detection of Salmonella sp. (day 0, psychrotrophic count, total and fecal coliforms at45°C, the acceptance sensory test (days 0 and 30, water activity, instrumental color, pH and lipid oxidation analysis (Thiobarbituric acid reactive substances - TBARS days 0, 5, 10, 15, 20, 25 and 30 of storage. Lipid oxidation (TBARS and water activity provided significant differences among storage days. However it was concluded that the bologna sausage remained stable and with acceptable quality for 30 days of storage may be a new alternative to adding value to fish products, because the researched microorganisms had a low count, changes in pH were not significant and sensory test indicated good acceptance of the product during the 30 days of storage.

Nutritive Value and Availability of Commonly Used Feed Ingredients ...

African Journals Online (AJOL)

Commonly utilized feed ingredients for culture of Nile tilapia (Oreochromis niloticus) and African catfish (Clarias gariepinus) from Kenya, Tanzania and Rwanda were collected over a period of six months (January - June 2010) and evaluated for their nutritive composition through proximate analysis. Most of the fish feed ...

Influência das densidades de estocagem e sistemas de aeração sobre o peso e características de carcaça da tilápia do Nilo (Oreochromis niloticus Linnaeus, 1757 Influence of stocking densities and aeration systems on Nile tilapia (Oreochromis niloticus, 1757

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Newton Castagnolli

1998-10-01

Full Text Available O experimento foi conduzido em nove tanques (38m2, durante 252 dias, com Oreochromis niloticus, revertidas para macho, pesando em média 16,3g, alimentadas com ração comercial (29,5% PB. Comparou-se a eficiência dos sistemas de aeração (A1=controle-sem aeração; A2=compressor radial e A3=chafariz, em três densidades de estocagem (D1=3 peixes/m3; D2=6 peixes/m3 e D3=9 peixes/m3, avaliadas através do peso final (PF dos peixes, peso de carcaça (PC, filé (PFI, pele (PP, gordura visceral (PGV e rendimentos de carcaça (RC e filé (RFI. O delineamento foi inteiramente casualizado, em esquema fatorial 3x3, com 30 repetições, sendo o peixe considerado a unidade experimental. O maior PF (530,27g e PC (431,22 foram obtidos na D1. O compressor radial (A2 foi significativamente mais eficiente do que os demais sistemas, para PF e PC, porém para PFI, somente foi significativamente mais eficiente na D2 (162,67g. O maior PGV (37,36g e PP (38,13g foram observados na D1 respectivamente, com A2 e A3. Para RC, não houve diferença entre as densidades e o A3 proporcionou o maior resultado, apesar de não diferir de A1. O RFI variou de 31,73% (A2D1 a 37,14% (A1D1 entre os tratamentos.A 252-day experiment was carried out in nine fish ponds with male sex-reversed Nile tilapia with 16.3g average weight and fed on commercial ration (29.5% crude protein. The efficiency of aeration systems (A1=non-aeration control; A2=radial compressor and A3=sprinkler was compared in three stocking densities (D1=3 fish/m3; D2=6 fish/m3 and D3=9 fish/m3, through the evaluation on their final weight (FW, carcass weight (CW, fillet weight (FIW, skin weight (SWO, visceral fat weight (VFW, carcass yield (CY and fillet yield (FIY. Plotting was completely randomized through a 3x3 factorial scheme, with 30 replications, and each fish was considered as an experimental unit. The heaviest FW (530.27g and CW (431.22g were obtained in D1. The radial compressor system was significantly

Morphological and molecular characterization of a novel myxosporean parasite Myxobolus bejeranoi n. sp. (Cnidaria: Myxosporea) from hybrid tilapia in Israel.

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Lövy, Alena; Smirnov, Margarita; Brekhman, Vera; Ofek, Tamir; Lotan, Tamar

2018-02-01

Myxosporean infections can cause severe damage to commercially grown tilapia. Here, we report a novel myxosporean that was found in gills of Oreochromis aureus male × Oreochromis niloticus female, which is an important aquaculture tilapia hybrid in Israel. Three-month-old fish were found to have cysts located in gill muscle tissue, which were filled with both immature and mature spores. Affected fish displayed higher mortality rate. Spore dimensions (10.8 ± 0.7 μm length × 6.8 ± 0.6 μm width) and molecular characterization using 18S ribosomal DNA revealed that the unknown parasite belongs in the Myxobolus clade. Based on the infection site, spore morphology and molecular characterization, we describe this parasite as Myxobolus bejeranoi n. sp. (MF401455). Phylogenetic analysis showed that the new species is most closely related to two Myxobolus spp. from O. niloticus in Egypt and Ghana.

Influence of insecticidal derivative (cartap hydrochloride) from the marine polycheate on certain enzyme systems of the fresh water fish Oreochromis mossambicus.

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Palanivelu, V; Vijayavel, K; Balasubramanian, S Ezhilarasi; Balasubramanian, M P

2005-04-01

The activities of phosphatases and transaminases were studied in muscle and liver of the fresh water fish, Oreochromis mossambicus on exposure to different sublethal concentrations (0.25, 0.5, 0.75 and 1 mgl(-1)) of cartap hydrochloride (insecticidal derivative from marine polycheate) for 96 h. There was an overall decrease in phosphatases and transaminases activity in muscle and liver of the fish subjected to cartap hydrochloride.

Study of risk of pollution by the heavy metals of the water and fishes of the Congo river

International Nuclear Information System (INIS)

Tuakashikila, M.; Mbuyi, K.M.; Kabwe, C.; Malumba, M.; Kapembo, L.; Lusamba, N.; Lundemba, S.; Barutti, Y.

2010-01-01

In order to conduct property this study, we have chosen to evaluate cadmium and lead concentration in Congo River water and un three species of fishes (Oreochromis niloticus nilotucus, Schilbe mystus and Campylomormyrus). These fishes have been collected from three sites in Congo River during the time from August to November 2009. Sample analysis (water and fishes) revealed that cadmium and concentration were lower then world heath organization (Who) acceptable standards. The campulomormyrus species present the highest lead concentration of all studied species and further mose this concentration has been found in Kinsuka. This could be justified by the position Kinsuka site which is the down stream section compared to Kinkole and Maluku position in Congo River. Therefor harmful effects are not expected in short time, however they are dangerous in long time because these metals are both toxic and cumulative, may damage concerned organs

Masculinização de larvas de tilápia do Nilo (Oreochromis niloticus por banhos de imersão e o andrógeno dissolvido em solução de dimetilsulfóxido (DMSO - DOI: 10.4025/actascianimsci.v26i2.1867 Masculinizaton of Nile tilápia fries (Oreochromis niloticus through bath immersion and androgen dissolved in dimethilsulfoxide (DMSO solution - DOI: 10.4025/actascianimsci.v26i2.1867

Directory of Open Access Journals (Sweden)

Fábio Meurer

2004-04-01

Full Text Available O experimento constituiu-se de dois ensaios. O primeiro objetivou determinar a concentração de dimetilsulfóxido não-prejudicial às larvas de tilápia do Nilo (Oreochromis niloticus L. para utilização em banhos de imersão, e o segundo avaliou a masculinização e o desempenho zootécnico das larvas submetidas à imersão em diferentes concentrações hormonais. Os animais foram imersos por 36 horas em recipientes de 0,5L, com 50 larvas. No primeiro ensaio, utilizaram-se as concentrações de 0,04%; 0,1%; 0,3%; 0,7% e 1,0% de dimetilsulfóxido, não apresentando diferença significativa (p>0,05 sobre resultados de sobrevivência entre os tratamentos. No segundo ensaio, utilizaram-se os tratamentos de 0,5; 1,5; 2,5; 3,5; 4,5 e 5,5mg de 17alpha-metiltestosterona.L-1, em solução de 0,04% de dimetilsulfóxido, verificando-se melhor resultado (p-1.This experiment was composed of two essays. The first one studied the deletrious effect of dimethylsulfoxide concentration on Nile tilapia (Oreochromis niloticus L. fries through bath immersion. The second assessed the sex reversal of male and the performance of Nile tilapia fries submitted to immersion in different hormone concentrations. The animals were immersed over 36 hours in recipients of 0.5L, with fifty fries. In the first essay dimethylsulfoxide concentrations of 0.04, 0.1, 0.3, 0.7 and 1.0% were utilized and there was no significant difference (p>0.05 in survival results between the treatments. In the second essay 0.5, 1.5, 2.5, 3.5, 4.5 and 5.5mg of 17alpha-metyltestosterone.L-1 were utilized in 0.04% dimethylsulfoxide solution, in which the best result (P-1

Total mercury distribution in different tissues of six species of freshwater fish from the Kpong hydroelectric reservoir in Ghana.

Science.gov (United States)

Atta, Alhassan; Voegborlo, Ray Bright; Agorku, Eric Selorm

2012-05-01

Total mercury concentrations were determined in seven tissues of 38 fish samples comprising six species from the Kpong hydroelectric reservoir in Ghana by cold vapour atomic absorption spectrometry technique using an automatic mercury analyzer. Mercury concentration in all the tissues ranged from 0.005 to 0.022 μg/g wet weight. In general, the concentration of mercury in all the tissues were decreasing in the order; liver > muscle > intestine > stomach > gonad > gill > swim bladder. Mercury concentration was generally greater in the tissues of high-trophic-level fish such as Clarotes laticeps, Mormyrops anguilloides and Chrysichthys aurutus whereas low-trophic-level fish such as Oreochromis niloticus recorded low mercury concentration in their tissues. The results obtained for total mercury concentration in the muscle tissues analysed in this study are below the WHO/FAO threshold limit of 0.5 μg/g. This suggests that the exposure of the general public to Hg through fish consumption can be considered negligible.

Use of implantable pellets to administer low levels of methyl mercury to fish

Energy Technology Data Exchange (ETDEWEB)

Arnold, B.S.; Jagoe, C.H.; Gross, T.S.

1999-07-01

Implantable pellets of methyl mercury chloride were tested in Nile Tilapia (oreochromis niloticus) to appraise the effectiveness of the method for chronic studies of mercury. Two dosing regimes of 15 and 1.5 grams/CH{sub 3}HgCl pellet (test 1) and 1 and 0.1 grams/pellet (tests 2--3) of methyl mercury chloride were used in three tests. Additional pellets containing only matrix were used as controls. The pellets were inserted into the peritoneal cavity along with a microchip for identification. Three methods of incision closure: sutures and two types of surgical glue, were tested. Pellets used in test one released the dose too fast, resulting in premature death of the fish. Results from tests 2 and 3 show blood mercury concentrations over time and tissue levels at necropsy consistent with dose suggestion that this is a viable method of dosing fish.

Cooperative and uniform fish? : social interactions and variability in live body weight in the GIFT strain (Nile tilapia, Oreochromic niloticus) in Malaysia

NARCIS (Netherlands)

Khaw, H.L.

2015-01-01

Abstract

Khaw, HL. (2014). Cooperative and uniform fish? Social interactions and variability in live body weight in the GIFT strain (Nile tilapia, Oreochromic niloticus) in Malaysia. PhD thesis, Wageningen University, the Netherlands.

Social interactions

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.

Histological variations in liver of freshwater fish Oreochromis mossambicus exposed to 60Co gamma irradiation

International Nuclear Information System (INIS)

Sadiq Bukhari, A.; Syed Mohamed, H.E.; Broos, K.V.; Stalin, A.; Singhal, R.K.; Venubabu, P.

2012-01-01

The irradiation effect of 60 Co at the three dose level of 3 mGy, 30 mGy and 300 mGy on the histology of liver of the freshwater fish Oreochromis mossambicus was investigated. The liver of O. mossambicus was dissected out and processed for light microscopy studies. 60 Co exposed O. mossambicus were found to result in several alterations in the histoarchitecture of liver. The alterations included mild congestion of blood vessels, structural alteration, cellular swelling, vacuolation and necrotic liver cells, indicating a definite response to 60 Co irradiation. The results suggest that the liver of O. mossambicus exposed to 60 Co were structurally altered with increasing dose levels. It is to record that alteration in the liver does not affect the physiology, behaviour or lethality of the individuals. Self regulating mechanisms would have influenced the liver to remain sustained. To confirm the same further studies in the direction by increasing dose level is required. - Highlights: ► Fish Oreochromis mossambicus irradiated to the dose of 3 mGy, 30 mGy and 300 mGy. ► Histoarchitecture of liver altered with increasing dose levels of 60 Co. ► Alteration in the liver does not affect the physiology, behaviour or lethality. ► Self regulating mechanisms might have prevented from Lethality. ► HSI index value for exposed group reported ( 60 Co.

Depletion of florfenicol amine in tilapia (Oreochromis sp.) maintained in a recirculating aquaculture system following Aquaflor(R)-medicated feed therapy (20 mg/kg BW/d for 10 days)

Science.gov (United States)

Gaikowski, Mark P.; Whitsel, Melissa K.; Charles, Shawn; Schleis, Susan M.; Crouch, Louis S.; Endris, Richard G.

2013-01-01

Aquaflor® [50% w w−1 florfenicol (FFC)], is approved for use in freshwater-reared warmwater finfish which include tilapia Oreochromis spp. in the United States to control mortality from Streptococcus iniae. The depletion of florfenicol amine (FFA), the marker residue of FFC, was evaluated after feeding FFC-medicated feed to deliver a nominal 20 mg FFC kg−1 BW d−1 dose (1.33× the label use of 15 mg FFC kg−1 BW d−1) to Nile tilapia O. niloticus and hybrid tilapia O. niloticus × O. aureus held in a recirculating aquaculture system (RAS) at production-scale holding densities. Florfenicol amine concentrations were determined in fillets taken from 10 fish before dosing and from 20 fish at nine time points after dosing (from 1 to 240 h post-dosing). Water samples were assayed for FFC before, during and after the dosing period. Parameters monitored included daily feed consumption and biofilter function (levels of ammonia, nitrite and nitrate). Mean fillet FFA concentration decreased from 13.77 μg g−1 at 1-h post dosing to 0.39 μg g−1 at 240-h post dosing. Water FFC concentration decreased from a maximum of 1400 ng mL−1 at 1 day post-dosing to 847 ng mL−1 at 240 h post-dosing. There were no adverse effects noted on fish, feed consumption or biofilter function associated with FFC-medicated feed administration to tilapia.

QUALITÉ NUTRITIVE DE L’ALIMENTATION NATURELLE DU TILAPIA OREOCHROMIS NILOTICUS EN ÉLEVAGE EXTENSIF DANS DES ÉTANGS DE BARRAGE (CÔTE D’IVOIRE

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BLE M. C.

2007-04-01

Full Text Available La composition chimique des sources alimentaires (périphyton, matières en suspension et sédiment et celle des contenus stomacaux d’Oreochromis niloticus en élevage extensif dans deux barrages situés en zone rurale (Gueyo, Sud-Ouest de la Côte d’Ivoire ont été déterminées afin d’apprécier la qualité de la nourriture naturelle ingérée par ces poissons. Les proportions des différents constituants chimiques mesurés dans ces trois sources alimentaires laissent apparaître la part importante que représentent les matières organiques hydrolysables dans le périphyton (65 et 67 % aux barrages 1 et 2, respectivement, alors que les matières minérales constituent plus de la moitié du poids sec total des matières en suspension (59 et 63 % et de la ressource sédimentaire (76 et 63 %. Sur les deux sites, les fibres représentent moins de 15 % de ces trois ressources. Les teneurs en protéines (19 % et le ratio Protéines/Énergie (17 mg.kJ-1 observés dans la ressource périphytique sont respectivement 2 et 3 fois supérieurs aux valeurs mesurées dans les deux autres ressources. L’analyse biochimique des contenus stomacaux montre que les protéines sont présentes en très faibles proportions dans la nourriture ingérée par O. niloticus (7 et 11 % dans les deux barrages. Par contre, les proportions en fibres (12 et 16 % et lipides (11 et 8 % de même que les ratios Protéines/Énergie (6 et 12 mg.kJ-1 caractérisant l’alimentation semblent répondre aux exigences de croissance chez cette espèce de tilapia. Les poids moyens des poissons en fin de cycle d’élevage traduisent la capacité d’O. niloticus à présenter une croissance correcte à partir d’une alimentation pauvre en matières azotées pourvu qu’une faible densité soit appliquée dans les sites d’élevage.

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...... contained copra meal at 680 g kg-1 inclusions for a 6-week period. One of the copra meal diets contained sesame meal supplementation (CM+S) as a natural high source of methionine which is the first limiting essential amino acid in copra meal. Results: The dietary treatments had no differential effects...... on growth, feed intake, or feed utilization parameters in O. niloticus. With the exception of the significantly higher lipid content of the CM+S group, the whole body compositions of the different fish groups were not significantly affected by the different dietary treatments. Remarkably, the high dietary...

Performance e retenção de metais pesados em três linhagens de juvenis de tilápia-do-Nilo em hapas - DOI: 10.4025/actascianimsci.v30i3.455 Performance of fingerling of Nile tilapia (Oreochromis niloticus, gift, chitralada and bouake strains in hapas - DOI: 10.4025/actascianimsci.v30i3.455

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Affonso Celso Gonçalves Júnior

2008-11-01

Full Text Available O trabalho objetivou avaliar o desempenho produtivo de três linhagens de tilápia-do-Nilo (Oreochromis niloticus, GIFT, Bouaké e Chitralada, durante a produção de juvenis no período de fevereiro a maio de 2007. Os alevinos sexualmente revertidos foram alojados em 12 hapas com 9 m3, instaladas em um tanque escavado com 0,7 ha de lâmina de água. Ao final de 93 dias de cultivo, verificou-se que houve diferença significativa para a sobrevivência entre as três linhagens (p -1, conversão alimentar (1,80, 1,81 e 1,81 e biomassa final (19.594,79, 19.528,85 e 16.488,99 g não apresentaram diferenças significativas entre a GIFT, Bouaké e Chitralada, respectivamente. A média dos peixes com peso acima de 25 g superou 80% dos lotes, garantindo uniformidade e padronização dos juvenis. Nos peixes, os metais tóxicos cádmio e chumbo ficaram acima do limite tolerável, porém o metal cromo não foi detectado. A linhagem GIFT apresenta a melhor performance apenas em relação à sobrevivência, neste sistema de cultivo, porém com maior acúmulo de metais pesados em comparação às outras duas linhagens.This essay aimed to evaluate the productive performance of three Nile tilapia (Oreochromis niloticus strains, GIFT (Genetic Improvement of Farmed Tilapia, Bouake and Chitralada, during the production of juveniles from February to May, 2007. The sexually reverted fingerlings were stored in twelve 9 m3 hapas installed in a ponds with 0.7 ha water blade. At the end of 93 days of culture a significant change in survival among the three strains (P0.05. The average of fish weight more than 25g was over 80% of the lots, which guaranteed the juvenile uniformity and standardization. The toxic metals cadmium and lead were above the tolerable level in the fish, although the chromium metal was not detected. The GIFT strain presented the best performance in this culture system, although it contained high indexes of heavy metals in comparison with the other

Toxicological assessment of four common household surfactants on ...

African Journals Online (AJOL)

The acute toxicity of four common household liquid detergents coded as (FL, ML, MF and LC) was evaluated on two fish species; African Catfish (Clarias gariepinus) and Nile Tilapia (Oreochromis niloticus) fingerlings in a static bioassay. During the exposure period (96 hours), there was a remarkable rise of alkalinity from ...

Prevalence and Mean Intensity of Ectoparasite Infections in Pond ...

African Journals Online (AJOL)

A cross sectional study was carried out between September 2007 and September 2008 to investigate the prevalence and mean intensity of ectoparasite infections on the gills and skin of Nile tilapia (Oreochromis niloticus) in Morogoro, Tanzania. A total of 229 fish from 19 ponds were studied. Trichodina spp. and ...

Physiological response and microRNA expression profiles in head kidney of genetically improved farmed tilapia (GIFT, Oreochromis niloticus) exposed to acute cold stress.

Science.gov (United States)

Qiang, Jun; Cui, Yan T; Tao, Fan Y; Bao, Wen J; He, Jie; Li, Xia H; Xu, Pao; Sun, Lan Y

2018-01-09

Cold stress has a serious impact on the overwintering survival and yield of genetically improved farmed tilapia (GIFT, Oreochromis niloticus). Understanding the physiological and molecular regulation mechanisms of low-temperature adaptation is necessary to help breed new tolerant strains. The semi-lethal low temperature of juvenile GIFT at 96 h was determined as 9.4 °C. We constructed and sequenced two small RNA libraries from head kidney tissues, one for the control (CO) group and one for the 9.4 °C-stressed (LTS) group, and identified 1736 and 1481 known microRNAs (miRNAs), and 164 and 152 novel miRNAs in the CO and LTS libraries, respectively. We verify the expression of nine up-regulated miRNAs and eight down-regulation miRNAs by qRT-PCR, and found their expression patterns were consistent with the sequencing results. We found that cold stress may have produced dysregulation of free radical and lipid metabolism, decreased superoxide dismutase activity, reduced respiratory burst and phagocytic activity of macrophages, increased malondialdehyde content, and adversely affected the physiological adaptation of GIFT, eventually leading to death. This study revealed interactions among miRNAs and signal regulated pathways in GIFT under cold stress that may help to understand the pathways involved in cold resistance.

Genomic comparison of virulent and non-virulent Streptococcus agalactiae in fish.

Science.gov (United States)

Delannoy, C M J; Zadoks, R N; Crumlish, M; Rodgers, D; Lainson, F A; Ferguson, H W; Turnbull, J; Fontaine, M C

2016-01-01

Streptococcus agalactiae infections in fish are predominantly caused by beta-haemolytic strains of clonal complex (CC) 7, notably its namesake sequence type (ST) 7, or by non-haemolytic strains of CC552, including the globally distributed ST260. In contrast, CC23, including its namesake ST23, has been associated with a wide homeothermic and poikilothermic host range, but never with fish. The aim of this study was to determine whether ST23 is virulent in fish and to identify genomic markers of fish adaptation of S. agalactiae. Intraperitoneal challenge of Nile tilapia, Oreochromis niloticus (Linnaeus), showed that ST260 is lethal at doses down to 10(2) cfu per fish, whereas ST23 does not cause disease at 10(7) cfu per fish. Comparison of the genome sequence of ST260 and ST23 with those of strains derived from fish, cattle and humans revealed the presence of genomic elements that are unique to subpopulations of S. agalactiae that have the ability to infect fish (CC7 and CC552). These loci occurred in clusters exhibiting typical signatures of mobile genetic elements. PCR-based screening of a collection of isolates from multiple host species confirmed the association of selected genes with fish-derived strains. Several fish-associated genes encode proteins that potentially provide fitness in the aquatic environment. © 2014 John Wiley & Sons Ltd.

miR-122 promotes hepatic antioxidant defense of genetically improved farmed tilapia (GIFT, Oreochromis niloticus) exposed to cadmium by directly targeting a metallothionein gene

International Nuclear Information System (INIS)

Qiang, Jun; Tao, Yi-Fan; He, Jie; Xu, Pao; Bao, Jin-Wen; Sun, Yi-Lan

2017-01-01

Highlights: • MiR-122 regulated tilapia MT by directly targeting MT 3′UTR. • MiR-122 level was negatively related to MT level under Cd stress. • MiR-122 silencing caused up-regulation of MT expression. • MiR-122 loss relieved liver stress and stimulated antioxidant enzymes. - Abastract: MicroRNAs (miRNAs) are small, non-coding RNAs that regulate target gene expression by binding to the 3′untranslated region (3′UTR) of the target mRNA. MiRNAs regulate a large variety of genes, including those involved in liver homeostasis and energy metabolism. Down-regulated levels of hepatic miR-122 were found in genetically improved farmed tilapia (GIFT, Oreochromis niloticus) exposed to cadmium (Cd) stress. Here, we report for the first time that reduction of miR-122 post-transcriptionally increased metallothionein (MT) mRNA levels by binding to its 3′UTR, as shown by a 3′ UTR luciferase reporter assay. The expression levels of miR-122 were negatively related to MT levels in GIFT under Cd stress. We performed in vivo functional analysis of miR-122 by injecting the fish with a miR-122 antagomir. Inhibition of miR-122 levels in GIFT liver caused a significant increase in MT expression, affected white blood cell and red blood cell counts, and serum alanine and aspartate aminotransferase activities, and glucose levels, all of which may help to relieve Cd stress-related liver stress. miR-122 silencing modulated oxidative stress and stimulated the activity of antioxidant enzymes. Our findings indicate that miR-122 regulated MT levels by binding to the 3′UTR of MT mRNA, and this interaction affected Cd stress induction and the resistance response in GIFT. We concluded that miR-122 plays an important role in regulating the stress response in GIFT liver. Our findings may contribute to understanding the mechanisms of miRNA-mediated gene regulation in tilapia in response to environmental stresses.

miR-122 promotes hepatic antioxidant defense of genetically improved farmed tilapia (GIFT, Oreochromis niloticus) exposed to cadmium by directly targeting a metallothionein gene

Energy Technology Data Exchange (ETDEWEB)

Qiang, Jun, E-mail: Qiangj@ffrc.cn [Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi 214081, Jiangsu (China); Tao, Yi-Fan [Wuxi Fisheries College, Nanjing Agricultural University, Wuxi 214081 (China); He, Jie [Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi 214081, Jiangsu (China); Xu, Pao, E-mail: Xup@ffrc.cn [Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi 214081, Jiangsu (China); Bao, Jin-Wen [Wuxi Fisheries College, Nanjing Agricultural University, Wuxi 214081 (China); Sun, Yi-Lan [Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi 214081, Jiangsu (China)

2017-01-15

Highlights: • MiR-122 regulated tilapia MT by directly targeting MT 3′UTR. • MiR-122 level was negatively related to MT level under Cd stress. • MiR-122 silencing caused up-regulation of MT expression. • MiR-122 loss relieved liver stress and stimulated antioxidant enzymes. - Abastract: MicroRNAs (miRNAs) are small, non-coding RNAs that regulate target gene expression by binding to the 3′untranslated region (3′UTR) of the target mRNA. MiRNAs regulate a large variety of genes, including those involved in liver homeostasis and energy metabolism. Down-regulated levels of hepatic miR-122 were found in genetically improved farmed tilapia (GIFT, Oreochromis niloticus) exposed to cadmium (Cd) stress. Here, we report for the first time that reduction of miR-122 post-transcriptionally increased metallothionein (MT) mRNA levels by binding to its 3′UTR, as shown by a 3′ UTR luciferase reporter assay. The expression levels of miR-122 were negatively related to MT levels in GIFT under Cd stress. We performed in vivo functional analysis of miR-122 by injecting the fish with a miR-122 antagomir. Inhibition of miR-122 levels in GIFT liver caused a significant increase in MT expression, affected white blood cell and red blood cell counts, and serum alanine and aspartate aminotransferase activities, and glucose levels, all of which may help to relieve Cd stress-related liver stress. miR-122 silencing modulated oxidative stress and stimulated the activity of antioxidant enzymes. Our findings indicate that miR-122 regulated MT levels by binding to the 3′UTR of MT mRNA, and this interaction affected Cd stress induction and the resistance response in GIFT. We concluded that miR-122 plays an important role in regulating the stress response in GIFT liver. Our findings may contribute to understanding the mechanisms of miRNA-mediated gene regulation in tilapia in response to environmental stresses.

Major surfome and secretome profile of Streptococcus agalactiae from Nile tilapia (Oreochromis niloticus): Insight into vaccine development.

Science.gov (United States)

Li, Wei; Wang, Hai-Qing; He, Run-Zhen; Li, Yan-Wei; Su, You-Lu; Li, An-Xing

2016-08-01

Streptococcus agalactiae is a major piscine pathogen that is responsible for huge economic losses to the aquaculture industry. Safe recombinant vaccines, based on a small number of antigenic proteins, are emerging as the most attractive, cost-effective solution against S. agalactiae. The proteins of S. agalactiae exposed to the environment, including surface proteins and secretory proteins, are important targets for the immune system and they are likely to be good vaccine candidates. To obtain a precise profile of its surface proteins, S. agalactiae strain THN0901, which was isolated from tilapia (Oreochromis niloticus), was treated with proteinase K to cleave surface-exposed proteins, which were identified by liquid chromatography-tandem spectrometry (LC-MS/MS). Forty surface-associated proteins were identified, including ten proteins containing cell wall-anchoring motifs, eight lipoproteins, eleven membrane proteins, seven secretory proteins, three cytoplasmic proteins, and one unknown protein. In addition, culture supernatant proteins of S. agalactiae were separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and all of the Coomassie-stained bands were subsequently identified by LC-MS/MS. A total of twenty-six extracellular proteins were identified, including eleven secretory proteins, seven cell wall proteins, three membrane proteins, two cytoplasmic proteins and three unknown proteins. Of these, six highly expressed surface-associated and secretory proteins are putative to be vaccine candidate of piscine S. agalactiae. Moreover, immunogenic secreted protein, a highly expressed protein screened from the secretome in the present study, was demonstrated to induce high antibody titer in tilapia, and it conferred protection against S. agalactiae, as evidenced by the relative percent survival (RPS) 48.61± 8.45%. The data reported here narrow the scope of screening protective antigens, and provide guidance in the development of a novel

The Efficacy of Nile Tilapia (Oreochromis niloticus Broodstock and Larval Immunization against Streptococcus agalactiae and Aeromonas hydrophila

Directory of Open Access Journals (Sweden)

Wesly Pasaribu

2018-03-01

Full Text Available Streptococcus agalactiae and Aeromonas hydrophila have been recognized as the causative agents of mortality in tilapia larvae with single infection and coinfection. The objective of this study was to evaluate the efficacy of maternal transfer and offspring protection from the immunization of monovalent and bivalent vaccines on Nile tilapia (Oreochromis niloticus broodstock and larval immunization. Four groups of broodstock were intraperitoneally injected with formalin killed whole-cells of S. agalactiae (Sa group, A. hydrophila (Ah group, the bivalent mixed vaccine of them (Biv group, and phosphate-buffered saline as a control (Pbs group. Immunization of the larvae produced from immunized broodstock with a bivalent vaccine (Biv1 group and Pbs (Pbs1 group was performed by immersion at 20 days after hatch. Larvae produced from the Pbs group were unvaccinated as the control (Pbs2 group. Changes in the specific antibody and relative percent survival were measured. The Sa and Ah groups that could increase specific antibodies and protection against pathogenic bacteria were challenged with the homologous bacteria. The Biv group stimulated and protected against both S. agalactiae and A. hydrophila. The specific antibody of the Biv1 group was higher than the Pbs1 and Pbs2 groups. The last observation in this study showed that the relative percent survival of the Biv group after challenged S. agalactiae, A. hydrophila, and coinfection were 74.74 ± 3.18%, 73.81 ± 8.58%, and 71.48 ± 5.70%, respectively. The use of bivalent vaccines on the broodstock and larvae may be a strategy to reduce mortality in Nile tilapia larvae caused by single pathogen infection of S. agalactiae and A. hydrophila, or coinfection with both S. agalactiae and A. hydrophila.

Defumação da tilápia do Nilo (Oreochromis niloticus inteira eviscerada e filé: aspectos referentes às características organolépticas, composição centesimal e perdas ocorridas no processamento Smoking process of whole eviscerated and fillet of Nile tilapia (Oreochromis niloticus: organoleptic characteristics, proximate composition and losses during processing

Directory of Open Access Journals (Sweden)

Maria Luiza Rodrigues de Souza

2004-02-01

Full Text Available O objetivo do experimento foi avaliar o efeito da defumação da tilápia do Nilo (Oreochromis niloticus inteira eviscerada e filé sobre as características organolépticas (aparência, aroma, cor, sabor, textura, teor de sal e aceitação geral, a porcentagem de perda de peso (PP e composição centesimal. Foram comparados FP1 (peixe inteiro eviscerado, 5 horas de fumaça e FP2 (filé, 4 horas de fumaça. Os peixes foram descamados, eviscerados, para obtenção de FP1 ou filetados por uma única pessoa, para obtenção de FP2, e então submetidos à salmouragem úmida (30% e à defumação. O rendimento médio para FP1 e FP2 foi de 63,98 e 27,11%, respectivamente. O valor médio para porcentagem de perda de peso ocorrida na defumação para o filé (31,33% foi superior ao peixe inteiro (27,04%. A análise sensorial revelou que o peixe inteiro teve melhor aceitação quanto ao sabor e teor de sal e não diferiu do filé quanto ao aroma, cor e textura. O processo de defumação reduziu o conteúdo de umidade e proporcionou aumento nos teores de proteína bruta, lipídios e cinzas. As perdas foram maiores para o filé, que apresentou maior teor de proteína bruta e menor teor de lipídios comparado ao peixe inteiro. Verificou-se também que o sabor do filé pode ser melhorado em função de uma correção na salmouragem.The objective of the experiment was to evaluate the smoking process effect of whole eviscerated and fillet of Nile tilapia on the organoleptic characteristics (appearance, aroma, color, flavor, texture, salt content and general acceptance, percent weight loss (PP and proximate composition. FP1 (whole eviscerated fish, 5 hour smoking and FP2 (fillet, 4 hour smoking were compared. Scaled, eviscerated fish, FP1 and fillets cut by only one person, FP2 were submitted to brine (30% and smoking process. Average yield for FP1 and FP2 was 63.98% and 27.11%, respectively. Average loss weight during smoking for fillet (31.33% was higher

Effect of ions on the activity of brain acetylcholinesterase from tropical fish

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Caio Rodrigo Dias Assis

2015-07-01

Full Text Available Objective: To investigate the effect of ions on brain acetylcholinesterase (AChE; EC 3.1.1.7 activities from economic important fish [pirarucu, Arapaima gigas; tambaqui, Colossoma macropomum; cobia, Rachycentron canadum (R. canadum and Nile tilapia, Oreochromis niloticus (O. niloticus] comparing with a commercial enzyme from electric eel [Electrophorus electricus (E. electricus]. Methods: The in vitro exposure was performed at concentrations ranging from 0.001 to 10 mmol/L (except for ethylene diamine tetraacetic acid; up to 150 mmol/L. Inhibition kinetics on R. canadum and O. niloticus were also observed through four methods (Michaelis-Menten, Lineweaver-Burk, Dixon and Cornish-Bowden plots in order to investigate the type of inhibition produced by some ions. Results: Hg 2+ , As 3+ , Cu 2+ , Zn 2+ , Cd 2+ caused inhibition in all the species under study. Ca 2+ , Mg 2+ and Mn 2+ induced slight activation in R. canadum enzyme while Pb 2+ , Ba 2+ , Fe 2+ , Li + inhibited the AChE from some of the analyzed species. The lowest IC 50 and Ki values were estimated for E. electricus AChE in presence of Hg 2+ , Pb 2+ , Zn 2+ . Under our experimental conditions, the results for R. canadum and O. niloticus, As 3+ , Cu 2+ , Cd 2+ , Pb 2+ and Zn 2+ showed a non- competitive/mixed-type inhibition, while Hg 2+ inhibited the enzyme in a mixed/competitive- like manner. Conclusions: E. electricus AChE activity was affected by ten of fifteen ions under study showing that this enzyme could undergo interference by these ions when used as pesticide biosensor in environmental analysis. This hindrance would be less relevant for the crude extracts.

Food and feeding habits of Oreochromis mossambicus (Peters) in ...

African Journals Online (AJOL)

The diet of 745 Oreochromis mossambicus (Peters) of less than 0,5 up to 2000 g wet mass, in Hartbeespoort Dam, was determined from stomach content analysis. Samples of fish were selected to cover a whole annual cycle. Small fish fed initially on zoobenthos and zooplankton, but fish with a mass of over 4 g fed ...

Screening and identification of a microsatellite marker associated ...

Indian Academy of Sciences (India)

River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou 510380, People's Republic of China. Abstract .... cultured in the laboratory and then sexed by examination ..... embryonic development of Nile tilapia (Oreochromis niloticus). ... plex of the Nile tilapia (Oreochromis niloticus) allow orienta-.

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

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Kwasi Adu Obirikorang

2015-05-01

Full Text Available 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 dietary inclusion of soybean meal resulted in a significantly higher feed bulk density relative to the fishmeal control diet. The inclusions of copra and palm kernel meals, however, resulted in lower feed bulk densities. Sinking rates, water stabilities and nutrient retention efficiencies of feed pellets were directly related to feed bulk densities. The soybean meal diet had the fastest sinking velocities, greatest water stability and highest nutrient retention rates. The dietary inclusion of soybean meal, however, significantly impaired feed intake compared to the other three diets. Mean daily feed intakes of the control, palm kernel meal and copra meal diets corresponded to 28.88, 27.01 and 28.31 g during the experimental period and varied significantly from the mean daily intake of the soybean meal diet which corresponded to 20.01 g. Faecal matter production (g dry mass kg−1 ingested feed 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.

Geographical distribution of protozoan and metazoan parasites of farmed Nile tilapia Oreochromis niloticus (L.) (Perciformes: Cichlidae) in Yucatán, México.

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Paredes-Trujillo, Amelia; Velázquez-Abunader, Iván; Torres-Irineo, Edgar; Romero, David; Vidal-Martínez, Víctor Manuel

2016-02-03

In Yucatán State, southern México, as in many other parts of the world where tilapia has been introduced for aquaculture, the deficient application of management measures has led to the establishment of non-native parasites. The aims of this study were to describe the geographical distribution of protozoan and helminth parasites of farmed Nile tilapia Oreochromis niloticus (L.) throughout the Yucatán and to examine the potential statistical associations of the prevalence and mean abundance of these parasites with management and environmental variables. All 29 Nile tilapia farms currently operating in Yucatán were surveyed. Maps were created to describe the geographical location of the parasites infecting Nile tilapia at each farm. We evaluated the statistical associations of management and environmental variables with the mean abundance values of each parasite species using a multivariate redundancy analysis (RDA) and generalized additive models (GAM). We also used Ripley's K to determine whether there were significant clusters of the mean abundance of particular parasite species in specific regions of the Yucatán State. A total of 580 O. niloticus were examined, and 11 species of parasites were recorded. Cichlidogyrus sclerosus was the most frequent and abundant parasite at all 29 farms, whereas Gyrodactylus cichlidarum was found in 26 of the 29 farms. The RDA showed that the most important predictors were the concentration of nitrites and ammonium and the water exchange rate. The GAM showed the significant effect of the tank capacity, no use of quarantine area and no use of prophylactic treatments on the mean abundance of G. cichlidarum. The geographical distribution patterns of the mean abundance of most parasite species exhibited clustering near to the coast of Yucatán. Two groups of farms were distinguished: (i) farms with medium to high technology, where the most frequent and abundant parasite was G. cichlidarum, and (ii) farms with low technology

Bioaccumulation of persistent organic pollutants (POPs) in fish species from Lake Koka, Ethiopia: The influence of lipid content and trophic position

International Nuclear Information System (INIS)

Deribe, Ermias; Rosseland, Bjørn Olav; Borgstrøm, Reidar; Salbu, Brit; Gebremariam, Zinabu; Dadebo, Elias; Norli, Hans Ragnar; Eklo, Ole Martin

2011-01-01

The concentrations and bioaccumulation of persistent organic pollutants (POPs) were determined in four fish species from Lake Koka, Ethiopia, representing 2–3 levels in the food chain of the lake. Dichlorodiphenyltrichloroethanes (DDTs), endosulfans, polychlorinated biphenyls (PCBs) and chlorpyrifos were identified, with DDTs as the most predominant pesticide, with concentration ranging from 0.05 to 72.53 ng g −1 wet weight (ww). All fish tissue samples collected from different species of the lake contained residues of DDTs. The maximum level of DDTs was found in the fattiest, African sharptooth catfish (Clarias gariepinus) sampled from the lake, with a mean concentration of 15.15 ng g −1 ww. The significant (P 15 N indicates that DDTs biomagnified in the food web of the lake. The 4,4′-DDE to 4,4′-DDT ratio in Oreochromis niloticus (0.6) and Cyprinus carpio (0.5) were below 1, indicating ongoing use of DDTs in the study area and recent exposure of these fish species.

Biomagnification of some heavy and essential metals in sediments, fishes and crayfish from Ondo State coastal region, Nigeria

International Nuclear Information System (INIS)

Asaolu, S.S.; Olaofe, O.

2005-01-01

The bio magnifications levels of some essential (Fe, Zn, Cu) and toxic metals (Pb, Ni, Cd, Cr, Co, Mn) were determined in sediments, three kinds of fish (Oreochromis niloticus, Synodonthis sp., and Clarias gariepinus) and crayfish from the Ondo State coastal region. The metal bio magnification in the fish and crayfish was several times greater than in water, while that in the sediments was several thousand-folds greater than in both the organisms and water. Among the metals examined in water, Fe was the most abundant with average values of 146.7 and 74.3 mg/1, respectively, for wet and dry seasons, while Co was the least with average values of 2.4 and 1.6 mg/1. In the sediments, concentrations of Pb, Ni, Fe, Cr, Co and Mn in the wet season were relatively higher than those obtained for the dry season. Fe with an average of 50.9 mg/kg in C, gariepinus was the most abundant metal in the fish samples, while Cu with an average value of 0.3 mg/kg in O. niloticus was the least. The metal bio magnification for most of the metals for both seasons was found to vary widely from one location to the other. This was confirmed by the coefficient of variation that ranged from 31% to 144% and 29% to 130% in the wet and dry seasons, respectively. The present study has shown that fish, crayfish and sediments can be used to monitor the pollution level of metals in the Nigerian coastal water. (author)

Effect of probiotic microorganisms isolated from Hypostomus plecostomus in Oreochromis sp juveniles

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Yuri Vela-Gutiérrez

2017-01-01

Full Text Available Objective. The aim of this study was to assess the behavior of red tilapia juveniles (Oreochromis sp. in presence of the possible probiotic microorganisms isolated from the gastrointestinal tract of panche fish (Hypostomus plecostomus. Materials and methods. During the phase of assessment of probiotics, 120 red tilapia (Oreochromis sp juveniles were selected, with average weight of 1.28±0.22 g and average length of 2.99±0.27 cm. Three experimental treatments were formulated taking into account the nourishment needs of red tilapia (Oreochromis sp.. The statistical method employed was a completely random design. Results. The three strains of Lactobacillus genus (Lactobacillus plantarum, Lactobacillus pentosus, Lactobacillus rhamnosus isolated from the digestive tract of H. plecostomus, yielded diverse results in the biometrical variables considered, as well as in the SGR, PER, AE, AC. Conclusions. The best rapports regarding the gain in length were for the treatment with native probiotics, and it is deduced that they were easily settled in the intestines of the fish (Oreochromis sp.. It is also determined that there are significant differences in the results or gain in length for the Control Concentrate feed (CC against Concentrate feed plus Native Probiotic (CNP for red tilapia (Oreochromis sp. in the juvenile stag for a 30 day time span.

Substitution of Earthworm Meal with a Portion of Fishmeal in the Diet ...

African Journals Online (AJOL)

Fingerlings of Nile tilapia (Oreochromis niloticus) of mean weight 2.15±0.01g were fed on earthworm meal as a substitute for a portion of fishmeal for 10 weeks to determine the effect on growth and nutrient utilization. The fish were fed isonitrogenous Diets (40% crude protein) containing 10%, 15%, 25%, 30%, 40%, and 0% ...

Mercury in fish from three rift valley lakes (Turkana, Naivasha and Baringo), Kenya, East Africa

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Campbell, L.M.; Osano, O.; Hecky, R.E.; Dixon, D.G

2003-09-01

Mercury concentrations in Kenyan fish vary with tropic position but, in general, do not pose an unacceptable risk to human consumers of wildlife. -Total mercury (THg) concentrations were measured for various fish species from Lakes Turkana, Naivasha and Baringo in the rift valley of Kenya. The highest THg concentration (636 ng g{sup -1} wet weight) was measured for a piscivorous tigerfish Hydrocynus forskahlii from Lake Turkana. THg concentrations for the Perciformes species, the Nile perch Lates niloticus from Lake Turkana and the largemouth bass Micropterus salmoides from Lake Naivasha ranged between 4 and 95 ng g{sup -1}. The tilapiine species in all lakes, including the Nile tilapia Oreochromis niloticus, had consistently low THg concentrations ranging between 2 and 25 ng g{sup -1}. In Lake Naivasha, the crayfish species, Procambrus clarkii, had THg concentrations similar to those for the tilapiine species from the same lake, which is consistent with their shared detritivore diet. THg concentrations in all fish species were usually consistent with their known trophic position, with highest concentrations in piscivores and declining in omnivores, insectivores and detritivores. One exception is the detritivore Labeo cylindricus from Lake Baringo, which had surprisingly elevated THg concentrations (mean=75 ng g{sup -1}), which was similar to those for the top trophic species (Clarias and Protopterus) in the same lake. Except for two Hydrocynus forskahlii individuals from Lake Turkana, which had THg concentrations near or above the international marketing limit of 500 ng g{sup -1}, THg concentrations in the fish were generally below those of World Health Organization's recommended limit of 200 ng g{sup -1} for at-risk groups.

Feminilização de larvas de tilápia do Nilo (Oreochromis niloticus L. a partir de banhos de imersão com valerato-de-estradiol Feminization of larvae of Nile tilapia (Oreochromis niloticus L. by immersion baths with estradiol valerate

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Robie Allan Bombardelli

2005-04-01

Full Text Available Determinou-se o período ontogênico de maior sensibilidade das larvas de tilápias do Nilo (Oreochromis niloticus aos tratamentos de feminilização, por banhos de imersão de 36 horas, em solução contendo 2,0 mg de valerato-de-estradiol (VE.L-1. O experimento foi realizado em duas fases - a primeira com tratamentos hormonais e a segunda na fase de alevinagem. Foram utilizadas 1.200 larvas, provenientes de um mesmo lote de reprodutores, distribuídas em 24 recipientes plásticos de volume útil de 0,5 L, em um delineamento experimental inteiramente casualizado, composto por seis tratamentos e quatro repetições. Considerou-se a unidade experimental um recipiente plástico contendo 0,5 L de solução hormonal e 50 larvas. Os tratamentos constituíram-se no banho de imersão das larvas em diferentes fases ontogênicas, correspondentes a 175,2 UTAs (dias-grau ou 6,5 DPE (dias após a eclosão; 217,2 UTAs ou 8 DPE; 273,2 UTAs ou 10 DPE; 329,0 UTAs ou 12 DPE; 383,9 UTAs ou 14 DPE; e 438,1 UTAs ou 16 DPE. Após os tratamentos, as larvas foram cultivadas até atingirem comprimento-padrão de 25,0 mm, para posterior avaliação dos resultados. Os resultados de feminilização foram melhores para larvas mais jovens (6,5 DPE ou 175,2 UTAs, produzindo 39,20% de fêmeas, o que demonstra relação linear negativa entre o período ontogênico e a taxa de feminilização. Os índices de comprimento e peso final médio, fator de condição e sobrevivência não foram afetados pelos tratamentos. O período ontogênico mais adequado para a reversão sexual com VE correspondeu àquele em que as larvas apresentaram 175,2 UTAs ou 6,5 DPE, o que produziu 39,20% de fêmeas.An experiment was carried out to in two steps (the first was hormonal treatments and the other the larvae grow up phase to determine the best ontogenic periods for larvae of the Nile tilapia (Oreochromis niloticus regarding the feminization hormonal treatments by immersion baths during 36 hours

BIOMETRY AND COMPOSITION OF FISH SPECIES IN OWENA RESERVOIR, ONDO STATE, NIGERIA

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FAPOHUNDA Olawumi Oluwafunmilola

2007-11-01

Full Text Available A survey of fish species present in Owena reservoir was conducted between October 2004 and March 2005. Fish samples were taken from the catch of the fishermen operating in the reservoir. The results of the survey showed that 14 fish species belonging to seven families were recorded. Two families namely Characidae and Clariidae constituted the dominant fish families in the reservoir. Among the Characidae, Brycinus nurse (23.1% and among the Clariidae family, Clarias gariepinus (22.8% were dominant. Other fish species with significant abundance were Sarotherodon galilaeus (9.3%, Parachanna obscura (8.0%, Clarias anguillaris (7.7% and Oreochromis niloticus (6.4%. The meristic features of the two most abundant fish species caught are as follows: Brycinus nurse had two dorsal spines with eight dorsal fins, two anal spines with eleven anal fins, 25 caudal fins, one pectoral spine and 13 pectoral fins and two ventral spines with seven ventral fins. Clarias gariepinus had 75 dorsal fins, 31 anal fins, 10 caudal fins, six pectoral fins and five ventral fins. The morphometric features of the two most abundant fish species are: Brycinus nurse: total length: 312mm, standard length: 255mm, head length: 60mm, body length: 90mm and body girth: 190mm. Clarias gariepinus: total length: 265mm, standard length: 240mm, head length: 62mm, body length: 62mm and body girth: 130mm.

Metal contents in common edible fish species and evaluation of potential health risks to consumers

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Naglaa Farag Soliman

2015-12-01

Full Text Available Objective: To conduct a health risk assessment of some heavy metals attributed to consumption of common edible fish species available for consumers. Methods: Concentrations of Cd, Cr, Cu, Fe, Mn, Pb and Zn were determined in muscles, gills, livers, bones and skins of six common edible fish species, namely Oreochromis niloticus, Mugil cephalus, Sardinella aurita, Mullus barbatus, Boops boops, Pagrus pagrus. Concentrations of heavy metals were determined by atomic absorption spectrophotometer and expressed as µg/g of wet tissue. Results: Results showed that iron and zinc were the most abundant among all fish tissues under investigation. The data obtained in the present work were compared well with the counterpart data reported internationally. The estimated values of all metals in muscles of fish in this study were below the permissible limits. Moreover, the potential health risks of metals to human via consumption of seafood were assessed by estimating daily intake and target heath quotient. Generally, risk values for the measured metals do not pose unacceptable risks at mean ingestion rate for muscles. Conclusions: It can be concluded that the investigated metals in edible parts of the examined species have no health problems for consumers.

Induced cytochrome P450 1A activity in cichlid fishes from Guandu River and Jacarepaguá Lake, Rio de Janeiro, Brazil.

Science.gov (United States)

Parente, Thiago E M; De-Oliveira, Ana C A X; Paumgartten, Francisco J R

2008-03-01

The induction of cytochrome P4501A-mediated activity (e.g. ethoxyresorufin-O-deethylation, EROD) has been used as a biomarker for monitoring fish exposure to AhR-receptor ligands such as polycyclic aromatic hydrocarbons (PAH), polychlorinated biphenyls (PCB) and polychlorinated dibenzo-dioxins/furans (PCDD/Fs). In this study we found that hepatic EROD is induced in fish ("Nile tilapia", Oreochromis niloticus and "acará", Geophagus brasiliensis) from the Guandu River (7-17-fold) and Jacarepaguá Lake (7-fold), Rio de Janeiro, Brazil. Since both cichlid fish are consumed by the local population and the Guandu River is the main source of the drinking water supply for the greater Rio de Janeiro metropolitan area, pollution by cytochrome P4501A-inducing chemicals is a cause for concern and should be further investigated in sediments, water and biota. We additionally showed that EROD activity in the fish liver post-mitochondrial supernatant-simpler, cheaper and less time consuming to prepare than the microsomal fraction-is sufficiently sensitive for monitoring purposes.

Differential toxicity and influence of salinity on acute toxicity of ...

African Journals Online (AJOL)

Differential toxicity and influence of salinity on acute toxicity of copper sulphate and lead nitrate against Oreochromis niloticus. KA Bawa-Allah, F Osuala, J Effiong. Abstract. This study investigated the salinity-tolerance of Oreochromis niloticus and the influence of salinity changes on the acute toxicities of copper sulphate ...

The impact of a biomanipulation experiment on the ichthyofauna diet from a neotropical reservoir in Brazilian semiarid

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Cristiane de Carvalho Ferreira Lima Moura

2018-04-01

Full Text Available Abstract Aim To evaluate the impact of a biomanipulation experiment on the feeding of fish species from a neotropical semiarid reservoir, before and after the removal of the exotic species Oreochromis niloticus. Methods The values of Food Index were analyzed for six species: Oreochromis niloticus , Prochilodus brevis Steindachner,1875, Hypostomus cf. paparie Fowler,1941, Hoplias gr. malabaricus Bloch,1794, Astyanax bimaculatus Linnaeus,1758 and Leporinus piau Fowler,194. All data were obtained in two periods, before of the removal O. niloticus (May 2012 to January 2013 and after its removal (April 2013 to November 2013. The Morisita-Horn index was used to evaluate the feeding similarity among the six species and determine trophic categories (insectivorous, omnivorous, iliophaga and piscivora. To establish the probable variations due the presence of O. niloticus species, the Food Index of the six species was used in a Bray-Curtis similarity matrix. Through the Non-metric Multidimensional Scaling (NMDS we could not observe any differences among items consumed by different species. The Canonical Correspondence Analysis (CCA was used to assay the influence of environmental variables on the dietary, from the Food Index data. Results All species were classified in four trophic categories that do not shown any variation among the formed groups during studied periods. After the removal of Nile tilapia some species showed changes in food items, according to NMDS. The CCA indicated low association among the monthly Food Index of species and the environmental changes. Conclusion The process of biomanipulation on the Ecological Station from Serra Negra reservoir, which compares the dietaries from five local species before and after removal of exotic species Oreochromis niloticus, resulted in modification of dietary composition from three of five studied species.

Apparent digestibility coefficient of chickpea, maize, high-quality protein maize, and beans diets in juvenile and adult Nile tilapia ( Oreochromis niloticus

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Magnolia Montoya-Mejía

Full Text Available ABSTRACT The objective of our study was to assess the apparent digestibility of plant ingredients in diets for juvenile (50 g and adult (220 g Nile tilapia (Oreochromis niloticus. Dietary dry matter and protein apparent digestibility coefficients of four plant-derived feedstuffs (chickpea, maize, high-quality maize protein, and beans were tested. The beans diet had the lowest apparent digestibility coefficient of dry matter (ADCDM (69.41%, while no significant differences were detected in ADCDM among the other diets; ADCDM was significantly higher in adults compared with juveniles (77.02 vs. 73.76%. Apparent dry matter digestibility coefficient of ingredients (ADCI was significantly higher in the chickpea (70.48% and high-quality protein maize (71.09% ingredients, and lower in the beans (52.79% ingredient. Apparent dry matter digestibility coefficient of ingredients was significantly higher in juveniles compared with adults (72.56 vs. 56.80%. The protein digestibility of diet (ADCCP was significantly higher in the reference diet (93.68%, while the lowest corresponded to the maize (87.86% and beans (87.29% diets. Significantly lower apparent digestibility coefficient of protein (ADCICP was obtained with the high-quality maize protein (59.11% and maize (49.48% ingredients, while higher ADCICP was obtained with the chickpea and beans ingredients (71.31 and 63.89%, respectively. The apparent digestibility coefficient of ingredient crude protein ADCICP was significantly higher in juveniles compared with adults (67.35 vs. 53.46. Digestibility is generally higher in juveniles, and we recommend using chickpea as an ingredient in diets for Nile tilapia.

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. Copyright © 2016 Elsevier Ltd. All rights reserved.

Fish genomes provide novel insights into the evolution of vertebrate secretin receptors and their ligand.

Science.gov (United States)

Cardoso, João C R; Félix, Rute C; Trindade, Marlene; Power, Deborah M

2014-12-01

The secretin receptor (SCTR) is a member of Class 2 subfamily B1 GPCRs and part of the PAC1/VPAC receptor subfamily. This receptor has long been known in mammals but has only recently been identified in other vertebrates including teleosts, from which it was previously considered to be absent. The ligand for SCTR in mammals is secretin (SCT), an important gastrointestinal peptide, which in teleosts has not yet been isolated, or the gene identified. This study revises the evolutionary model previously proposed for the secretin-GPCRs in metazoan by analysing in detail the fishes, the most successful of the extant vertebrates. All the Actinopterygii genomes analysed and the Chondrichthyes and Sarcopterygii fish possess a SCTR gene that shares conserved sequence, structure and synteny with the tetrapod homologue. Phylogenetic clustering and gene environment comparisons revealed that fish and tetrapod SCTR shared a common origin and diverged early from the PAC1/VPAC subfamily group. In teleosts SCTR duplicated as a result of the fish specific whole genome duplication but in all the teleost genomes analysed, with the exception of tilapia (Oreochromis niloticus), one of the duplicates was lost. The function of SCTR in teleosts is unknown but quantitative PCR revealed that in both sea bass (Dicentrarchus labrax) and tilapia (Oreochromis mossambicus) transcript abundance is high in the gastrointestinal tract suggesting it may intervene in similar processes to those in mammals. In contrast, no gene encoding the ligand SCT was identified in the ray-finned fishes (Actinopterygii) although it was present in the coelacanth (lobe finned fish, Sarcopterygii) and in the elephant shark (holocephalian). The genes in linkage with SCT in tetrapods and coelacanth were also identified in ray-finned fishes supporting the idea that it was lost from their genome. At present SCTR remains an orphan receptor in ray-finned fishes and it will be of interest in the future to establish why SCT was

Induced cytochrome P450 1A activity in cichlid fishes from Guandu River and Jacarepagua Lake, Rio de Janeiro, Brazil

International Nuclear Information System (INIS)

Parente, Thiago E.M.; Oliveira, Ana C.A.X. de; Paumgartten, Francisco J.R.

2008-01-01

The induction of cytochrome P4501A-mediated activity (e.g. ethoxyresorufin-O-deethylation, EROD) has been used as a biomarker for monitoring fish exposure to AhR-receptor ligands such as polycyclic aromatic hydrocarbons (PAH), polychlorinated biphenyls (PCB) and polychlorinated dibenzo-dioxins/furans (PCDD/Fs). In this study we found that hepatic EROD is induced in fish ('Nile tilapia', Oreochromis niloticus and 'acara', Geophagus brasiliensis) from the Guandu River (7-17-fold) and Jacarepagua Lake (7-fold), Rio de Janeiro, Brazil. Since both cichlid fish are consumed by the local population and the Guandu River is the main source of the drinking water supply for the greater Rio de Janeiro metropolitan area, pollution by cytochrome P4501A-inducing chemicals is a cause for concern and should be further investigated in sediments, water and biota. We additionally showed that EROD activity in the fish liver post-mitochondrial supernatant-simpler, cheaper and less time consuming to prepare than the microsomal fraction-is sufficiently sensitive for monitoring purposes. - Increased EROD activity in the liver of cichlid fishes indicated that Guandu River, the source of drinking water supply for Rio de Janeiro is polluted by CYP1A-inducing chemicals

beta-adrenoceptors mediate inhibition of lipolysis in adipocytes of tilapia (Oreochromis mossambicus)

NARCIS (Netherlands)

Vianen, GJ; Obels, PP; Van Den Thillart, GEEJM; Zaagsma, J

The regulation of triglyceride mobilization by catecholamines was investigated in the teleost fish Oreochromis mossambicus (tilapia) in vivo and in vitro. In vitro experiments were carried out with adipocytes that were isolated for the first time from fish adipose tissue. For the in vivo

COMPARISON AND INTERACTION GENOTIPE-ENVIRONMENT OF THE PRODUCTIVE PERFORMANCE IN THREE GENETIC LINES OF TILAPIA Oreochromis sp.

Directory of Open Access Journals (Sweden)

Jorge Luis Pérez-Fuentes

2016-05-01

Full Text Available Tilapia is the second most widely cultivated species in the international scope, due to their fast growing and breeding capacity in captivity. Its biggest problem is the unpredictability of the productive performance of varieties in different environments and management types. For this reason, the productive performance of three lines: Oreochromis niloticus (N, red Oreochromis mossambicus (M and Rocky Mountain (R, cultured in five sites in two environments (Presses: Miguel de la Madrid and Miguel Aleman in the State of Oaxaca, Mexico was compared. Cages with dimensions between 18 and 48 m3 with stocking density of 7 to 28 fish m-3 were used. Feeding varied depending on the producers (1 to 3 portions a day/cage (300 to 1200 g of feed. Total length (TL, weight (P, survival (SUP and fillet yield (RF were evaluated in each genetic line. Results from physicochemical parameters of water, environments of culture and production efficiency of the strains indicated no significant differences, except for weight gain (g between sites of culture. However, it was considered that the differences were mainly due to handling during the culture, rather than the genetic line. Genetic lines showed similar performance (Tilapia R: LT 16.5 ± 3.1 cm, P 99.0± 46.6 g, 28 % RF, SUP 91.6 %. Tilapia N: LT 16.7 ± 3.7 cm, P 98.2 ± 40.9, RF 23 % SUP 86 %. Tilapia M: LT 15.4 ± 4.6 cm, P 100.1 ± 112.5 g, 30 % RF, SUP 91.6 %. Under the conditions evaluated, type of management could influence the efficiency of the culture more than the genetic line.

Bioaccumulation of persistent organic pollutants (POPs) in fish species from Lake Koka, Ethiopia: The influence of lipid content and trophic position

Energy Technology Data Exchange (ETDEWEB)

Deribe, Ermias, E-mail: ermias.weldemariam@umb.no [Norwegian University of Life Sciences, Department of Plant and Environmental Sciences, P.O. Box 5003, N-1432, As (Norway); Hawassa University, Faculty of Natural Sciences, Department of Applied Biology, P.O. Box 5, Awassa (Ethiopia); Rosseland, Bjorn Olav; Borgstrom, Reidar [Norwegian University of Life Sciences, Department of Ecology and Natural Resource Management, P.O. Box 5003, N-1432, As (Norway); Salbu, Brit [Norwegian University of Life Sciences, Department of Plant and Environmental Sciences, P.O. Box 5003, N-1432, As (Norway); Gebremariam, Zinabu [Higher Education Strategy Center (HESC) P.O. Box 32742, Addis Ababa (Ethiopia); Hawassa University, Faculty of Natural Sciences, Department of Applied Biology, P.O. Box 5, Awassa (Ethiopia); Dadebo, Elias [Hawassa University, Faculty of Natural Sciences, Department of Applied Biology, P.O. Box 5, Awassa (Ethiopia); Norli, Hans Ragnar [Norwegian Institute for Agricultural and Environmental Research, Plant Health and Plant Protection Division, Pesticide Chemistry Section, Hogskoleveien 7, N-1432 As (Norway); Eklo, Ole Martin [Norwegian University of Life Sciences, Department of Plant and Environmental Sciences, P.O. Box 5003, N-1432, As (Norway); Norwegian Institute for Agricultural and Environmental Research, Plant Health and Plant Protection Division, Pesticide Chemistry Section, Hogskoleveien 7, N-1432 As (Norway)

2011-12-01

The concentrations and bioaccumulation of persistent organic pollutants (POPs) were determined in four fish species from Lake Koka, Ethiopia, representing 2-3 levels in the food chain of the lake. Dichlorodiphenyltrichloroethanes (DDTs), endosulfans, polychlorinated biphenyls (PCBs) and chlorpyrifos were identified, with DDTs as the most predominant pesticide, with concentration ranging from 0.05 to 72.53 ng g{sup -1} wet weight (ww). All fish tissue samples collected from different species of the lake contained residues of DDTs. The maximum level of DDTs was found in the fattiest, African sharptooth catfish (Clarias gariepinus) sampled from the lake, with a mean concentration of 15.15 ng g{sup -1}ww. The significant (P < 0.05) relationship between concentrations of DDTs and {delta}{sup 15}N indicates that DDTs biomagnified in the food web of the lake. The 4,4 Prime -DDE to 4,4 Prime -DDT ratio in Oreochromis niloticus (0.6) and Cyprinus carpio (0.5) were below 1, indicating ongoing use of DDTs in the study area and recent exposure of these fish species.

Evaluation of the Effect of Replacing Maize with Cattle Rumen ...

African Journals Online (AJOL)

This study determined the nutritive values of cattle rumen waste (CRW) meal used for replacement of maize in the diets of Nile tilapia Oreochromis niloticus. CRW (20.9% CP) was used to replace maize (10.1 CP) at 0%, 25%, 50%, 75% and 100% making diets (D1-D5). The diets were fed to the fish (5.59±0.37g) to apparent ...

Organic matter sedimentation and resuspension in Tilapia (Oreochromis niloticus) fish ponds during a growing cycle

NARCIS (Netherlands)

Jimenez-Montealegre, R.; Verdegem, M.C.J.; Zamora, J.E.; Verreth, J.A.J.

2002-01-01

The rates of sedimentation and resuspension of organic carbon and total nitrogen were measured in earthen fishponds, based on nutrient input, water quality parameters and fish size and biomass. Material collected in sediment traps and soil samples were analyzed for organic carbon, total nitrogen,

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 tilapia fed CP and CCP. These results suggest that 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.

Determinación y prevalencia de Mycobacterium spp., en tilapia nilótica (Oreochromis niloticus cultivada en Campeche, México

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Maurilio Lara-Flores

2013-03-01

Full Text Available Objetivo. Determinar la presencia y prevalencia de Mycobacterium spp., en granjas de tilapia nilótica (Oreochromis niloticus en el Municipio de Champotón, Campeche, México. Materiales y métodos. La colecta de organismos se realizó en tres granjas de cultivo de tilapia nilótica del municipio de Champotón, Campeche, México. Los organismos se examinaron externa e internamente y se tomó una muestra de riñón la cual fue sembrada en forma de estría en medios de cultivo: Löwesntein-Jensen, TCBS, KF y en TSA; las placas fueron incubadas a 35°C de 24 a 48 horas, los órganos fueron fijados en formalina tamponada al 10% para ser procesados para histología de rutina para análisis posteriores. Asimismo, muestras de cultivo bacteriológico y de tejido fueron teñidas con la técnica de Ziel-Neelsen con el fin de observar la presencia de bacilos ácido-alcohol resistentes. Resultados. Los resultados obtenidos sugieren que la presencia de Mycobacterium spp., es constante y en alta prevalencia y puede ser un factor que este mermando la rentabilidad del cultivo. Conclusiones. La presencia de Mycobacterium spp., representa un riesgo para el cultivo de tilapia en el municipio de Champotón, por ser una enfermedad muy persistente y difícil de erradicar una vez ocurrido e brote de infección, por lo cual es importante llevar estudios más detallados de la presencia de este género bacteriano, así como, medidas de prevención y dispersión de este patógeno en los cultivos adyacentes.

Identification and characterization of lipid metabolism-related microRNAs in the liver of genetically improved farmed tilapia (GIFT, Oreochromis niloticus) by deep sequencing.

Science.gov (United States)

Tao, Yi-Fan; Qiang, Jun; Yin, Guo-Jun; Xu, Pao; Shi, Qiong; Bao, Jing-Wen

2017-10-01

MicroRNAs (miRNAs) play vital roles in modulating diverse metabolic processes in the liver, including lipid metabolism. Genetically improved farmed tilapia (GIFT, Oreochromis niloticus), an important aquaculture species in China, is susceptible to hepatic steatosis when reared in intensive culture systems. To investigate the miRNAs involved in GIFT lipid metabolism, two hepatic small RNA libraries from high-fat diet-fed and normal-fat diet-fed GIFT were constructed and sequenced using high-throughput sequencing technology. A total of 204 known and 56 novel miRNAs were identified by aligning the sequencing data with known Danio rerio miRNAs listed in miRBase 21.0. Six known miRNAs (miR-30a-5p, miR-34a, miR-145-5p, miR-29a, miR-205-5p, and miR-23a-3p) that were differentially expressed between the high-fat diet and normal-fat diet groups were validated by quantitative real-time PCR. Bioinformatics tools were used to predict the potential target genes of these differentially expressed miRNAs, and Gene Ontology enrichment analysis indicated that these miRNAs may play important roles in diet-induced hepatic steatosis in GIFT. Our results provide a foundation for further studies of the role of miRNAs in tilapia lipid homeostasis regulation, and may help to identify novel targets for therapeutic interventions to reduce the occurrence of fatty liver disease in farmed tilapia. Copyright © 2017. Published by Elsevier Ltd.

Characterization of catalytic efficiency parameters of brain cholinesterases in tropical fish.

Science.gov (United States)

de Assis, Caio Rodrigo Dias; Linhares, Amanda Guedes; Oliveira, Vagne Melo; França, Renata Cristina Penha; Santos, Juliana Ferreira; Marcuschi, Marina; Carvalho, Elba Verônica Matoso Maciel; Bezerra, Ranilson Souza; Carvalho, Luiz Bezerra

2014-12-01

Brain cholinesterases from four fish (Arapaima gigas, Colossoma macropomum, Rachycentron canadum and Oreochromis niloticus) were characterized using specific substrates and selective inhibitors. Parameters of catalytic efficiency such as activation energy (AE), k(cat) and k(cat)/k(m) as well as rate enhancements produced by these enzymes were estimated by a method using crude extracts described here. Despite the BChE-like activity, specific substrate kinetic analysis pointed to the existence of only acetylcholinesterase (AChE) in brain of the species studied. Selective inhibition suggests that C. macropomum brain AChE presents atypical activity regarding its behavior in the presence of selective inhibitors. AE data showed that the enzymes increased the rate of reactions up to 10(12) in relation to the uncatalyzed reactions. Zymograms showed the presence of AChE isoforms with molecular weights ranging from 202 to 299 kDa. Values of k(cat) and k(cat)/k(m) were similar to those found in the literature.

Micronuclei and erythrocytic abnormalities frequencies of freshwater fishes: Establishing a baseline for health status

Science.gov (United States)

Sousa, Debora Batista Pinheiro; Torres, Audalio Rebelo; Oliveira, Suelen Rosana Sampaio; Castro, Jonatas da Silva; Neta, Raimunda Nonata Fortes Carvalho

2017-11-01

Majority papers shows that micronucleus test and erythrocyte abnormalities are excellent tools such as tools for monitor fish health and the level of impact in aquatic ecosystems. Nevertheless, still do not know the baseline for those changes in freshwater fishes communities in the Brazilian Northeastern river. In this study, we show the level of basis of two species of freshwater fishes (Colossoma macropomum -tambaqui and Oreochromis niloticus - tilápia) with the aim of establish levels of background these species. The animals were collected from Ambude river in the protected area and blood collected from all fish for analysis. Erythrocyte indices—mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), and mean corpuscular hemoglobin concentration (MCHC)—were calculated. Blood samples from all fish were examined for micronuclear changes after Giemsa staining. Micronuclei were found in fish from from Ambude River. The baseline values determined for tambaqui was (micronuclei= 0.0071±0.0026; MCV=0.0073±0.0037; MCHV=0.0071±0.0024) and tilapia (micronuclei= 0.0061±0.0026; MCV=0.0037±0.0017; MCHV=0.056±0.0036). We belive that, we propose using the genotoxic approach for estimating fish health status as the technique allows examination in locus of live fish without the need for animal euthanasia. Besides, baseline level can be to establish levels of background and patterns to pathological and physiological research of these species in future biomonitoring programs.

Oxidative stress biomarkers and aggressive behavior in fish exposed to aquatic cadmium contamination

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Jeane A. Almeida

Full Text Available The objective of this study was to investigate the possible link between cadmium exposure, hepatic markers of oxidative stress and aggressive behavior in Nile tilapia (Oreochromis niloticus. Fish were first exposed to 0.75 mg/L CdCl2 for 15 days (12 isolated fish for each group and afterward a behavioral test was performed. Fish from the control and cadmium-exposed groups were paired for 1 h (6 pairs of fish per group for determination of aggressiveness parameters. Immediately after the behavioral test, the animals were sacrificed and the liver was used to determine biochemical parameters. Cadmium decreased aggression in Nile tilapia. Subordinate animals exposed to cadmium showed decreased glutathione peroxidase (GSH-Px activity compared to dominant ones. No alterations were observed in selenium-dependent glutathione peroxidase Se-GSH-P and Cu-Zn superoxide dismutase activities, but total superoxide dismutase activity was increased in subordinate animals exposed to cadmium compared to subordinate control. Catalase activity was increased in cadmium-exposed fish. Lipoperoxide concentrations also increased in cadmium exposed fish indicating that cadmium toxicity may affect oxidative stress biomarkers in Nile tilapia. Social stress induced lipoperoxidation in Nile tilapia, and subordinate animals exposed to cadmium responded with lower activities of liver antioxidant enzymes compared to dominant fish. The present study shows that cadmium exposure is capable of inducing changes in the social status and oxidative stress parameters in this species.

A three-dimensional stereotaxic MRI brain atlas of the cichlid fish Oreochromis mossambicus.

Science.gov (United States)

Simões, José M; Teles, Magda C; Oliveira, Rui F; Van der Linden, Annemie; Verhoye, Marleen

2012-01-01

The African cichlid Oreochromis mossambicus (Mozambique tilapia) has been used as a model system in a wide range of behavioural and neurobiological studies. The increasing number of genetic tools available for this species, together with the emerging interest in its use for neurobiological studies, increased the need for an accurate hodological mapping of the tilapia brain to supplement the available histological data. The goal of our study was to elaborate a three-dimensional, high-resolution digital atlas using magnetic resonance imaging, supported by Nissl staining. Resulting images were viewed and analysed in all orientations (transverse, sagittal, and horizontal) and manually labelled to reveal structures in the olfactory bulb, telencephalon, diencephalon, optic tectum, and cerebellum. This high resolution tilapia brain atlas is expected to become a very useful tool for neuroscientists using this fish model and will certainly expand their use in future studies regarding the central nervous system.

ACOUSTIC CLASSIFICATION OF FRESHWATER FISH SPECIES USING ARTIFICIAL NEURAL NETWORK: EVALUATION OF THE MODEL PERFORMANCE

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Zulkarnaen Fahmi

2013-06-01

Full Text Available Hydroacoustic techniques are a valuable tool for the stock assessments of many fish species. Nonetheless, such techniques are limited by problems of species identification. Several methods and techniques have been used in addressing the problem of acoustic identification species and one of them is Artificial Neural Networks (ANNs. In this paper, Back propagation (BP and Multi Layer Perceptron (MLP of the Artificial Neural Network were used to classify carp (Cyprinus carpio, tilapia (Oreochromis niloticus, and catfish (Pangasius hypothalmus. Classification was done using a set of descriptors extracted from the acoustic data records, i.e. Volume Back scattering (Sv, Target Strength (TS, Area Back scattering Strength, Skewness, Kurtosis, Depth, Height and Relative altitude. The results showed that the Multi Layer Perceptron approach performed better than the Back propagation. The classification rates was 85.7% with the multi layer perceptron (MLP compared to 84.8% with back propagation (BP ANN.

Induced cytochrome P450 1A activity in cichlid fishes from Guandu River and Jacarepagua Lake, Rio de Janeiro, Brazil

Energy Technology Data Exchange (ETDEWEB)

Parente, Thiago E.M.; Oliveira, Ana C.A.X. de [Laboratorio de Toxicologia Ambiental, Escola Nacional de Saude Publica - FIOCRUZ, Av Brasil 4036, Predio de Expansao do Campus, Rio de Janeiro, RJ 21041-361 (Brazil); Paumgartten, Francisco J.R. [Laboratorio de Toxicologia Ambiental, Escola Nacional de Saude Publica - FIOCRUZ, Av Brasil 4036, Predio de Expansao do Campus, Rio de Janeiro, RJ 21041-361 (Brazil)], E-mail: paum@ensp.fiocruz.br

2008-03-15

The induction of cytochrome P4501A-mediated activity (e.g. ethoxyresorufin-O-deethylation, EROD) has been used as a biomarker for monitoring fish exposure to AhR-receptor ligands such as polycyclic aromatic hydrocarbons (PAH), polychlorinated biphenyls (PCB) and polychlorinated dibenzo-dioxins/furans (PCDD/Fs). In this study we found that hepatic EROD is induced in fish ('Nile tilapia', Oreochromis niloticus and 'acara', Geophagus brasiliensis) from the Guandu River (7-17-fold) and Jacarepagua Lake (7-fold), Rio de Janeiro, Brazil. Since both cichlid fish are consumed by the local population and the Guandu River is the main source of the drinking water supply for the greater Rio de Janeiro metropolitan area, pollution by cytochrome P4501A-inducing chemicals is a cause for concern and should be further investigated in sediments, water and biota. We additionally showed that EROD activity in the fish liver post-mitochondrial supernatant-simpler, cheaper and less time consuming to prepare than the microsomal fraction-is sufficiently sensitive for monitoring purposes. - Increased EROD activity in the liver of cichlid fishes indicated that Guandu River, the source of drinking water supply for Rio de Janeiro is polluted by CYP1A-inducing chemicals.

New approach for monitoring fish stress: A novel enzyme-functionalized label-free immunosensor system for detecting cortisol levels in fish.

Science.gov (United States)

Wu, Haiyun; Ohnuki, Hitoshi; Ota, Shirei; Murata, Masataka; Yoshiura, Yasutoshi; Endo, Hideaki

2017-07-15

Fishes display a wide variation in their physiological responses to stress, which is clearly evident in the plasma corticosteroid changes, chiefly cortisol levels in fish. As a well-known indicator of fish stress, a simple and rapid method for detecting cortisol changes especially sudden increases is desired. In this study, we describe an enzyme-functionalized label-free immunosensor system for detecting fish cortisol levels. Detection of cortisol using amperometry was achieved by immobilizing both anti-cortisol antibody (selective detection of cortisol) and glucose oxidase (signal amplification and non-toxic measurement) on an Au electrode surface with a self-assembled monolayer. This system is based on the maximum glucose oxidation output current change induced by the generation of a non-conductive antigen-antibody complex, which depends on the levels of cortisol in the sample. The immunosensor responded to cortisol levels with a linear decrease in the current in the range of 1.25-200ngml -1 (R=0.964). Since the dynamic range of the sensor can cover the normal range of plasma cortisol in fish, the samples obtained from the fish did not need to be diluted. Further, electrochemical measurement of one sample required only ~30min. The sensor system was applied to determine the cortisol levels in plasma sampled from Nile tilapia (Oreochromis niloticus), which were then compared with levels of the same samples determined using the conventional method (ELISA). Values determined using both methods were well correlated. These findings suggest that the proposed label-free immunosensor could be useful for rapid and convenient analysis of cortisol levels in fish without sample dilution. We also believe that the proposed system could be integrated in a miniaturized potentiostat for point-of-care cortisol detection and useful as a portable diagnostic in fish farms in the future. Copyright © 2016 Elsevier B.V. All rights reserved.

Environmental blue light prevents stress in the fish Nile tilapia

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Volpato G.L.

2001-01-01

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

Effects of coating chitosan inhibition to quality of fish fillet Oreochromis niloticus at room temperature storage

Science.gov (United States)

Saputra, Eka; Tjahjaningsih, Wahju; Patmawati

2017-02-01

Fresh fish shelf life can be extended by adding antibacterial compounds such as synthetic chemicals or natural materials. One of the natural ingredients that are safe to use to prolong the freshness of the fish is chitosan. Chitosan is able to provide quality deterioration inhibitory effect of fillet of tilapia. The rate of decline in the value of organoleptic fillet of tilapia treated chitosan solution is slower when compared to no treatment tilapia fillet chitosan solution. In the organoleptic test until the 18 hours of storage, 2% chitosan solution capable of maintaining the highest organoleptic value for the parameter sightings meat, texture, and smell fillet. The use of 2% chitosan solution provided the best results based on the parameters of the appearance of meat, the texture, the smell, the pH value and the value of TVB fillet.

The correlation between subordinate fish eye colour and received attacks: a negative social feedback mechanism for the reduction of aggression during the formation of dominance hierarchies.

Science.gov (United States)

Miyai, Caio A; Carretero Sanches, Fábio H; Costa, Tânia M; Colpo, Karine Delevati; Volpato, Gilson L; Barreto, Rodrigo E

2011-12-01

Eye darkening has been linked to social status in fish. The subordinate's eyes darken, while the eyes of the dominant fish become pale. Although this phenomenon has been described in salmonid fishes and in the African cichlid Nile tilapia Oreochromis niloticus, it is unclear whether eye darkening correlates with a reduction in aggressive behaviour. Thus, we evaluated the link between social status and eye darkening. We evaluated whether the eye colours of subordinate fish correlate with the frequency of received attacks in a neotropical fish, the pearl cichlid Geophagus brasiliensis. We paired pearl cichlids and quantified both the aggressive behaviour and the eye darkening of each fish. As has been described for Nile tilapia and Atlantic salmon, a clear-cut hierarchical relationship formed, where dominance and subordination were associated with pale and dark eye colours, respectively. Initially, eye colour darkening was positively correlated with the frequency of received attacks; however, a negative association occurred following eye darkening, in which the intensity of aggressive interactions decreased. Thus, fish that initially received a high number of attacks signalled subordination more rapidly and intensely (rapid and dramatic eye darkening), thereby inducing a negative social feedback mechanism that led to reduced aggression. Copyright © 2011 Elsevier GmbH. All rights reserved.

Comparison of the in vivo and in vitro genotoxicity of glyphosate isopropylamine salt in three different organisms.

Science.gov (United States)

Alvarez-Moya, Carlos; Silva, Mónica Reynoso; Ramírez, Carlos Valdez; Gallardo, David Gómez; Sánchez, Rafael León; Aguirre, Alejandro Canales; Velasco, Alfredo Feria

2014-03-01

There is considerable controversy with regard to the genotoxicity of glyphosate, with some reports stating that this compound is non-toxic for fish, birds and mammals. In this work, we used the comet assay to examine the genotoxicity of glyphosate isopropylamine (0.7, 7, 70 and 700 μM) in human lymphocytes, erythrocytes of Oreochromis niloticus and staminal nuclei of Tradescantia (4430) in vitro and in vivo. Cells, nuclei and fish that had and had not been exposed to 5 mM N-nitrosodiethylamine (NDEA) were used as positive and negative controls, respectively. Significant (p cell types and organisms tested. Human lymphocytes and Tradescantia hairs showed lower genetic damage in vivo compared to in vitro, possibly because of efficient metabolization of the herbicide. In O. niloticus erythrocytes, significant (p cells and organisms studied at concentrations of 0.7-7 μM.

Residues of lindane and endosulfan in water and fish samples from rivers, farms in Besease, Agogo and Akomadan in the Ashanti region of Ghana

International Nuclear Information System (INIS)

Osafo-Acquaah, S.; Frimpong, E.

1997-01-01

Pesticide residue analyses were performed on water and fish samples from River Oda in Besease, River Aframso in Nobewam near Kumasi, River Atwetwe in Akomadan, and River Kowire at Agogo. Residues of lindane and endosulfan were found in water and fish (Oreochromis niloticus, Tilapia zillii, Barbus trispulis, Heterobranchus sp., Tilapia busumana, Ophiocephalus obscura and Chana obscura) samples. The residues of lindane varied between the years and months in the year but were in the range of 0.3 - 15 ng L -1 (1993-94) and 8.7-32.0 ng L -1 (1995) for the water samples and 0.2-24 ng g -1 (1993-93) and 8.4-120.4 ng g -1 (1995) for the fish samples. Residues of endosulfan in the water and the fish samples were zero in 1993-1994 but, in 1995, were in the range of 6.4-35.2 ng L -1 for the water samples and 5.0-267.5 ng g -1 for the fish samples. In all cases the lindane and ensofulfan concentrations in the water were 10,000-20,000 times lower than known toxic concentration levels and therefore unlikely to cause fish toxicity problems. (author). 11 refs, 4 tabs

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

African Journals Online (AJOL)

Administrator

2011-09-26

Sep 26, 2011 ... worm water food fish and exceeding the harvest of. Atlantic salmon ... transgenic fish, in theory, is not different from the natural processes, but it is a ..... delivered from fast growing genetically-modified Tilapia zillii: A productive ...

Comparison of the growth of males and females of tilapia Oreochromis Niloticus cultured in cages

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Carlos Alvarado-Ruiz

2015-01-01

Full Text Available With the purpose of evaluating productive performance and potential weight gain capacity of snapper O. Niloticus without reversing, we evaluated the growth of males and females raised in floating cages in captivity grouped by gender. The experiment was conducted for a term of 150 days.  We used a simple 4 836 alevins of 26.2±19.7g, fish that were nourished until they visibly reached sexual differentiation to 119.3±56.5 g to be separated by sex and nourished in floating cages to a final average weight of 387.0±128.9g (harvestto determine differences in growth. The weight distribution of the undefined gender sample showed a decrease in the coefficient of variation (CV of 75.13% to 31.49 and 30.22 for males and females respectively. This indicates that the distribution of sizes of the samples tended to become normal during the cycle of harvest. Significant differences (P=0.05 for the weight of harvest 429.2±135.1g and 339.65±102.64 g.   For the growth rate 2.74±0.86g day y 2.18±0.68 g day were determined between males and females respectively. The standard error of the estimation of the difference of average weight between males and females was 89.62±7.23g for an accuracy level of 95%. Males displayed  better growth rate and weight gain for harvest.

Pathological analysis, detection of antigens, FasL expression analysis and leucocytes survival analysis in tilapia (Oreochromis niloticus) after infection with green fluorescent protein labeled Streptococcus agalactiae.

Science.gov (United States)

Wang, Jingyuan; Wu, Jinying; Yi, Liyuan; Hou, Zengxin; Li, Wensheng

2017-03-01

The pathogenesis of Streptococcus agalactiae infection in tilapia has not been fully described. To understand this, we investigated the clinic-pathological features of acute experimental septicemia in tilapia (Oreochromis niloticus) after receiving an intra-peritoneal injection with S. agalactiae THN-1901GFP. Immunohistochemistry and sections of pathological tissues were used to estimate the level of damage in the head-kidney, liver, spleen and trunk-kidney. The expression of FasL was analyzed by western blotting in these samples based on their damage levels. Leucocytes were isolated from the head-kidney and incubated with S. agalactiae THN-1901GFP. Then, phagocytosis, programmed cell death and the expression of FasL were analyzed. The infected tissues showed varying degrees of necrosis and histolysis. The serous membrane of the intestine was dissolved by S. agalactiae THN-1901GFP. Antigens of S. agalactiae THN-1901GFP accumulated in different parts of the infected organs. In the head-kidney and spleen, the expression of FasL was up-regulated in parallel with increased tissue damage. After being incubated with S. agalactiae THN-1901GFP, the phagocytic capacity and ability were both very high and the expression of FasL remained high in leucocytes. S. agalactiae THN-1901GFP was able to survive for a long period of time after being engulfed by phagocytic cells. These findings offer insight into the pathogenesis of S. agalactiae infection in tilapia. Copyright © 2017 Elsevier Ltd. All rights reserved.

Whole-body calcium flux rates in cichlid teleost fish Oreochromis mossambicus adapted to freshwater

International Nuclear Information System (INIS)

Flik, G.; Fenwick, J.C.; Kolar, Z.; Mayer-Gostan, N.; Wendelaar Bonga, S.E.

1985-01-01

Radiotracer techniques were used to measure influx and efflux rates of Ca 2+ in freshwater-adapted Oreochromis mossambicus. The influx rate of Ca 2+ is related to body weight (W) as Fin = 50W0.805 nmol Ca 2+ /h. For a 20-g fish the calculated influx rate was 558 nmol Ca 2+ /h, and this was attributed largely to extraintestinal uptake since the drinking rate was estimated to be only 28 microliter water/h, which corresponds to an intake of 22.4 nmol Ca 2+ /h. The Ca 2+ efflux rate was calculated using the initial rate of appearance of radiotracer in the ambient water and the specific activity of plasma Ca 2+ . Tracer efflux rates were constant over 6-8 h, which indicated that there was no substantial loss of tracer in either the urine or the feces because this would have resulted in random bursts of tracer loss. Efflux rates then primarily represent integumentary and presumably branchial efflux rates. The efflux rate of Ca 2+ is related to body weight as Fout = 30W0.563 nmol Ca 2+ /h, which means an efflux rate of 162 nmol Ca 2+ /h for a 20-g fish. The net whole-body Ca 2+ influx, calculated as Fnet = Fin - Fout, was 396 nmol/h for a 20-g fish, which proves that the ambient water is an important source of Ca 2+

Detoxification and antioxidant effects of garlic and curcumin in Oreochromis niloticus injected with aflatoxin B₁ with reference to gene expression of glutathione peroxidase (GPx) by RT-PCR.

Science.gov (United States)

El-Barbary, Manal I

2016-04-01

The present study aims to investigate the effects of both garlic and curcumin through evaluating their therapeutic properties as antioxidants on liver and kidney functions, hepatic antioxidants and GPx gene expression against aflatoxicosis of O. niloticus. In total, 180 of tilapia were divided into ten groups; T1 represented the negative control fed on a basal diet, and T2 was injected with a single intraperitoneal (i.p.) dose of AFB1 (6 mg/kg b.w.). Fish in T3-T6 were fed on a basal diet supplemented with both garlic (T3 and T4) and curcumin (T5 and T6) at the two concentrations of 10 and 20 g/kg diet, respectively. Fish in T7-T10 groups were injected with AFB1 and fed on the garlic (T7 and T8) and curcumin (T9 and T10) dietaries. The results showed that AFB1 has significant potency for increasing the activity of plasma AST, ALT, creatinine and uric acid values, and hepatic MDA as well as for reducing the concentrations of plasma TP, AL, GL and hepatic activity of TAC, while AFB1 led to up-regulated GPx gene expression when compared to the control (T1). These harmful effects of AFB1 were alleviated due to the garlic and curcumin dietaries in some studied parameters. Garlic reflected the highest induction of gene expression (T7); however, curcumin showed significant down-regulated (T9). These results concluded that the effects of garlic were better than curcumin at the two concentrations and the low concentration of them is more beneficial than the high concentration when it used against AFB1 in O. niloticus.

Morfometrik lima species ikan yang dominan tertangkap di Danau Aneuk Laot, Kota Sabang

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Auliyanisa Khayra

2016-08-01

Full Text Available Abstract. The objective of the present study was to analyze the morphometric variationsof five predominant fish species caught in Lake Aneuk Laot, Sabang City,Weh Island.The study was conducted in December 2015 to January 2016. The survey method was used in this study. The fish target were Nile tilapia (Oreochromis niloticus, tilapia (O. mossambicus, snakeskin gourami (Trichopodus pectoralis, giant gourami (Osphronemus goramy and snakehead (Channa striata. The fish samples were catched using gillnets. The fish sample were analyzed for traditional and truss network morphometrics. The results showed that there is closed morphological relationship between Nile tilapia and tilapia, and between snakeskin gourami and giant gourami, while the snakehead fish was discriminated apart from the two previous groups. Keywords: Morphometric Nile tilapia, tilapia, snakeskin gourami, giant gourami, snakehead fish, Weh Island   Abstrak. Penelitian ini bertujuan untuk menganalisis variasi morfologi ikan hasil tangkapan dominan di Danau Aneuk Laot Kota Sabang dengan menggunakan teknik traditional dan truss morphometric. Penelitian dilakukan pada Desember 2015 sampai Januari 2016. Ikan sampel terdiri dari ikan nila (Oreochromis niloticus, ikan mujair (O. mossambicus, ikan sepat siam (Trichopodus pectoralis, ikan gurami (Osphronemus gorami dan ikan gabus (Channa striata. Ikan sampel diperoleh dengan menggunakan alat tangkap jaring. Sebanyak 12 karakter traditional morphometric and 14 karakter truss dianalisis dalam penelitian ini.  Hasil penelitian menunjukkan terdapat tiga kelompok ikan, kelompok pertama ikan nila dan ikan mujair, kedua ikan ini kemiripan yang tinggi; kelompok kedua adalah ikan sepat siam dan ikan gurami, kelompok ketiga adalah ikan gabus yang memiliki kemiripan yang jauh dengan kedua kelompok ikan sebelumnya. Kata kunci: Morfometrik, Nila, mujair, sepat siam, gurami, gabus, Pulau Weh

TECHNOLOGY CHARACTERIZATION OF THE FISH FARM OF THE MUNICIPALITY OF CAPITÃO POÇO, PARÁ, BRAZIL

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Tiago Pereira Brito

2017-07-01

Full Text Available The present study describes the technological aspects of fish farming developed on the Capitão Poço in northeastern state of Pará. The data were collected through 17 semi-structured interviews in aquaculture properties in the region.The farmer was legally responsible for most property. The property's operating time ranged from 3 to 20 years and the time of experience in aquaculture activity from 10 months to 20 years (mean 5.4 ± 2.9 years. Aquaculture represented a secondary activity is for subsistence or to supplement the family income. The properties had a total area ranging from 0.5 to 750 hectares (average 124.9 ± 150.0 ha, with water area between 0.00165 and 2.16 ha (average 0.4944 ± 0.5694 ha. The semi-intensive production system was predominant (88.2%, however, the intensive system keeper tanks was also recorded (11.8%, and recorded both monocultures (70.6% as policultives (29, 4%, with cultive of Oreochromis niloticus, Colossoma macropomum, Leporinus friderici and two species hybrid. The management with regard to the analysis of water quality of farming, food supply and evaluation of growth performance, although carried out were not satisfactory, requiring greater technical training to producers. Keywords Amazon; aquaculture; farmer fish; fish; cultivation system.

Studies on the fisheries and biology of Oreochromis urolepsis ...

African Journals Online (AJOL)

The fisheries and some aspects of the biology of Oreochromis urolepsis of the Mtera Reservoir (Tanzania) were examined in August 2002. It was observed that there was no proper management of the reservoir\\'s fisheries. Beach seine fishing dominated the fishery. Nearly all the O. urolepsis caught by this type of gear were ...

Resistance of Nile tilapia (Oreochromis niloticus) to Streptococcus iniae and S. agalactiae Ib is heritable but not correlated

Science.gov (United States)

Tilapia (Oreochromis sp.) are an important source of protein with an economic value approaching US $8 billion yearly. Streptococcal disease, caused by Streptococcus iniae and S. agalactiae (both Gram positive bacteria), is an emerging or re-emerging disease negatively affecting tilapia aquaculture w...

Resistance of Nile tilapia (Oreochromis niloticus) to Streptococcus iniae and S. agalatiae Ib is heritable but not correlated

Science.gov (United States)

Tilapia (Oreochromis sp.) are an important source of protein with an ecomonic value approaching US $8 billion yearly. Streptococcal disease, caused by Streptococcus iniae and S. agalactiae (both Gram positive bacteria), is an emerging or re-emerging disease negatively affecting tilapia aquaculture w...

Piscinoodinium pillulare (Schäperclaus, 1954 Lom, 1981 (Dinoflagellida infection in cultivated freshwater fish from the Northeast region of São Paulo State, Brazil: parasitological and pathological aspects

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M. L. MARTINS

Full Text Available The Aquaculture Center of Unesp, Jaboticabal, SP, Brazil, received fishes for diagnosis from fish farmers reporting fish crowding at pond edges and in water inlets. Fifty-three out of 194 cases showed round to oval, immobile whitish structures, measuring up to 162 mm diameter, identified as the dinoflagellate Piscinoodinium pillulare. In 34 diagnosed cases the parasites were present in the gills, in 2 on body surface, and 9 in both. Thirty-one out of 53 were tambacu hybrids hosts; 7, Piaractus mesopotamicus; 6, Colossoma macropomum; 5, Leporinus macrocephalus; 3, Oreochromis niloticus; and 1, Prochilodus lineatus. Fish showed increased mucous production on body surface and gills, while ecchymosis in the caudal peduncle and operculum was present. The gills also showed paleness, congestion, and petechiae. Histopathology presented a great number of trophonts situated between secondary lamellae, fixed to or detached from the epithelium. Primary lamellae presented interstitial hemorrhages, severe hyperplasia of the epithelium, goblet cells, and mononuclear infiltrates. The present work is the first report of P. pillulare in Brazil and emphasizes the importance of this dinoflagellate which caused significant economic losses from 1995 through 1997.

Hazard assessment of metals in invasive fish species of the Yamuna River, India in relation to bioaccumulation factor and exposure concentration for human health implications.

Science.gov (United States)

Singh, Atul K; Srivastava, Sharad C; Verma, Pankaj; Ansari, Abubakar; Verma, Ambrish

2014-06-01

Monitoring of heavy metals was conducted in the Yamuna River considering bioaccumulation factor, exposure concentration, and human health implications which showed contamination levels of copper (Cu), lead (Pb), nickel (Ni), and chromium (Cr) and their dispersion patterns along the river. Largest concentration of Pb in river water was 392 μg L(-1); Cu was 392 μg L(-1) at the extreme downstream, Allahabad and Ni was 146 μg L(-1) at midstream, Agra. Largest concentration of Cu was 617 μg kg(-1), Ni 1,621 μg kg(-1) at midstream while Pb was 1,214 μg kg(-1) at Allahabad in surface sediment. The bioconcentration of Cu, Pb, Ni, and Cr was observed where the largest accumulation of Pb was 2.29 μg kg(-1) in Oreochromis niloticus and 1.55 μg kg(-1) in Cyprinus carpio invaded at Allahabad while largest concentration of Ni was 174 μg kg(-1) in O. niloticus and 124 μg kg(-1) in C. carpio in the midstream of the river. The calculated values of hazard index (HI) for Pb was found more than one which indicated human health concern. Carcinogenic risk value for Ni was again high i.e., 17.02 × 10(-4) which was larger than all other metals studied. The results of this study indicated bioconcentration in fish due to their exposures to heavy metals from different routes which had human health risk implications. Thus, regular environmental monitoring of heavy metal contamination in fish is advocated for assessing food safety since health risk may be associated with the consumption of fish contaminated through exposure to a degraded environment.

Accumulation of heavy metals in freshwater fish in cage aquaculture at Cirata Reservoir, West Java, Indonesia.

Science.gov (United States)

Salami, Indah Rachmatiah Siti; Rahmawati, Suphia; Sutarto, Ratri Indri Hapsari; Jaya, Pinilih Marendra

2008-10-01

Freshwater fish demand in West Java is supported by cage aquaculture in reservoirs. Cirata Reservoir is one of three cascading hydropower reservoirs built along the Citarum River that receives domestic and industrial wastes. Water pollution by heavy metals, such as copper and lead, increases the health risk of humans who consume the fish. The study was aimed to evaluate the concentration of copper and lead in fish, specifically on Cyprinus carpio, that are widely cultivated in the Cirata Reservoir. Two sizes of fish were collected from five sampling points around floating-cage area. The liver of the fish was found to contain the highest copper level, followed by gills, skin, and muscle. In contrast, lead was also high in the liver, followed by skin, gills, and the muscle, but the copper concentration found in the tissues studied was much higher (31.111 +/- 17.911 mg/kg dry wt) than the lead content (0.290 +/- 0.346 mg/kg dry wt). The concentration of metals in smaller fish was always higher than than that in bigger fish. The metals content was also compared to those in fish exposed in a semistatic laboratory-scale study using Oreochromis niloticus. After 28 days exposure with 0.01 mg Cu/L, fish accumulated 21.53 mg Cu/kg dry wt, whereas for Pb exposure of 0.016 mg/L, fish accumulated up to 7 mg/kg dry wt. However, estimates of Cu and Pb intake from C. carpio consumption were still below the average daily intake (ADI) limit. This study suggested that monitoring of water quality and heavy metals in cultured fish is important in protecting human health.

Intestinal transcriptome analysis revealed differential salinity adaptation between two tilapiine species.

Science.gov (United States)

Ronkin, Dana; Seroussi, Eyal; Nitzan, Tali; Doron-Faigenboim, Adi; Cnaani, Avner

2015-03-01

Tilapias are a group of freshwater species, which vary in their ability to adapt to high salinity water. Osmotic regulation in fish is conducted mainly in the gills, kidney, and gastrointestinal tract (GIT). The mechanisms involved in ion and water transport through the GIT is not well-characterized, with only a few described complexes. Comparing the transcriptome of the anterior and posterior intestinal sections of a freshwater and saltwater adapted fish by deep-sequencing, we examined the salinity adaptation of two tilapia species: the high salinity-tolerant Oreochromis mossambicus (Mozambique tilapia), and the less salinity-tolerant Oreochromis niloticus (Nile tilapia). This comparative analysis revealed high similarity in gene expression response to salinity change between species in the posterior intestine and large differences in the anterior intestine. Furthermore, in the anterior intestine 68 genes were saltwater up-regulated in one species and down-regulated in the other species (47 genes up-regulated in O. niloticus and down-regulated in O. mossambicus, with 21 genes showing the reverse pattern). Gene ontology (GO) analysis showed a high proportion of transporter and ion channel function among these genes. The results of this study point to a group of genes that differed in their salinity-dependent regulation pattern in the anterior intestine as potentially having a role in the differential salinity tolerance of these two closely related species. Copyright © 2015 Elsevier Inc. All rights reserved.

Arthropod pests of dried fish and fish by product in a tropical urban ...

African Journals Online (AJOL)

A four months research survey of arthropod pests infesting dried fish sold in a tropical urban community market (Ogige), Nsukka, Ngeria showed that 10 genera o dried freshwater fish (Synodontis, Hemisynodontis, Oreochromis, Hepsetus, Gymnarchus, Labeo, Protopterus, Heterobranchus, Alestes, Heterotis) and two ...

Study of the Antimicrobial Activity of Tilapia Piscidin 3 (TP3) and TP4 and Their Effects on Immune Functions in Hybrid Tilapia (Oreochromis spp.)

Science.gov (United States)

Pan, Chieh-Yu; Tsai, Tsung-Yu; Su, Bor-Chyuan; Hui, Cho-Fat; Chen, Jyh-Yih

2017-01-01

To address the growing concern over antibiotic-resistant microbial infections in aquatic animals, we tested several promising alternative agents that have emerged as new drug candidates. Specifically, the tilapia piscidins are a group of peptides that possess antimicrobial, wound-healing, and antitumor functions. In this study, we focused on tilapia piscidin 3 (TP3) and TP4, which are peptides derived from Oreochromis niloticus, and investigated their inhibition of acute bacterial infections by infecting hybrid tilapia (Oreochromis spp.) with Vibrio vulnificus and evaluating the protective effects of pre-treating, co-treating, and post-treating fish with TP3 and TP4. In vivo experiments showed that co-treatment with V. vulnificus and TP3 (20 μg/fish) or TP4 (20 μg/fish) achieved 95.3% and 88.9% survival rates, respectively, after seven days. When we co-injected TP3 or TP4 and V. vulnificus into tilapia and then re-challenged the fish with V. vulnificus after 28 days, the tilapia exhibited survival rates of 35.6% and 42.2%, respectively. Pre-treatment with TP3 (30 μg/fish) or TP4 (20 μg/fish) for 30 minutes prior to V. vulnificus infection resulted in high survival rates of 28.9% and 37.8%, respectively, while post-treatment with TP3 (20 μg/fish or 30 μg/fish) or TP4 (20 μg/fish) 30 minutes after V. vulnificus infection yielded high survival rates of 33.3% and 48.9%. In summary, pre-treating, co-treating, and post-treating fish with TP3 or TP4 all effectively decreased the number of V. vulnificus bacteria and promoted significantly lower mortality rates in tilapia. The minimum inhibitory concentrations (MICs) of TP3 and TP4 that were effective for treating fish infected with V. vulnificus were 7.8 and 62.5 μg/ml, respectively, whereas the MICs of kanamycin and ampicillin were 31.2 and 3.91 μg/ml. The antimicrobial activity of these peptides was confirmed by transmission electron microscopy (TEM) and scanning electron microscopy (SEM), both of which showed

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

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...

STUDY ON THE THERMAL STABILITY OF EPA AND DHA IN MUJAHIR (Oreochromis mossambicus FISH OIL

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Ngatidjo Hadipranoto

2010-06-01

Full Text Available EPA (Eicosapentaenoic acid and DHA (Docosahexaenoic acid content in common fresh water fish : mujahir (Oreochromis mossambicus after indirect heating were analysed. The aims of this study were to determine the effect of indirect heating process and α-tocopherol additions on both fatty acid stability.Lipids content in the mujahir fillets were extracted by Folch method using chloroform-metanol (2:1 mixture. Fatty acids in fish oil were converted to fatty acid methyl esters and then injected into gas chromatography to determine the EPA and DHA concentration. Operating condition of gas chromatography were programmed as follows: injection port temperature at 270 oC, detector at 280 oC, initial column temperature at 200 oC, and the final at 280 oC, the carrier gas was helium with flow rate of 10 ml per minute and temperature of column was increased gradually at 10 oC per minute. The effect of α-tocopherol addition on the stability of EPA and DHA was studied by adding α-tocopherol at 50 to 200 mg per kilogram sample before indirect heating process was carried out.The analysis of mujahir fish oil showed that the content of EPA and DHA in 100 grams fresh sample was 105 and 406,5 mg respectivelly. Indirect heating caused the EPA and DHA content decreased significantly. The addition of α-tocopherol results in a positive corelation between α-tocopherol concentration added and the decrease of EPA and DHA content during the heating process.   Keywords: fatty acid, eicosapentaenoic acid, docosahexaenoic acid

Trophic transfer of cadmium from duckweed (Lemna Minor L.) to Tilapia (Oreochromis mossambicus)

NARCIS (Netherlands)

Xue, Yan; Peijnenburg, Willie J G M; Huang, Jin; Wang, Dengjun; Jin, Yan

2018-01-01

The transfer of the toxic heavy metal Cd from duckweed (Lemna minor L.) to the freshwater fish tilapia (Oreochromis mossambicus) was investigated. Concentrations of Cd in different chemical forms in duckweed and in different tissues (gut, edible muscle, and remnants) of tilapia, i.e.,

Experimental infection of Aphanomyces invadans and susceptibility in seven species of tropical fish

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Seyedeh F. Afzali

2015-09-01

Full Text Available Aim: Epizootic ulcerative syndrome (EUS causes by aquatic oomycete fungus, Aphanomyces invadans is a dangerous fish disease of a wide range of fresh and brackish water, wild and farmed fish throughout the world. The objective of the present study was to determine the susceptibility of a number of tropical fish species to the EUS and compare the severity of infection between experimental groups. Materials and Methods: Snakehead, Channa striata (Bloch, 1793; snakeskin gourami, Trichopodus pectoralis (Regan, 1910; koi carp, Cyprinus carpio (Linnaeus, 1758; broadhead catfish, Clarias macrocephalus (Günther, 1864; goldfish, Carassius auratus (Linnaeus, 1758; climbing perch, Anabas testudineus (Bloch, 1792; and Nile tilapia, Oreochromis niloticus (Linnaeus, 1758 were challenged by intramuscular injection using zoospores of Aphanomyces invadans (NJM9701. The infected fish skins and muscles were examined for EUS histopathological characteristics, and the results on the severity of lesions and mortality were analyzed using SPSS program. Results: All zoospore-injected fish were shown to be susceptible to the EUS infection except Nile tilapia. Although, the general histopathological pattern was similar in the zoospore-injected group, but there were some variation in granulomatous reaction, that is the presence or absence of giant cells, and time of mortality were detected. The result of statistical analysis showed that there was a significant difference between species, (c2=145.11 and p<0.01. Conclusion: Gourami, koi carp, and catfish were demonstrated to be highly susceptible while goldfish and climbing perch were found to be moderately susceptible to the EUS infection. These findings suggested that the cellular response of fish to mycotic infection and granulomatous reaction varied in different fish species, which could not be an indicator of susceptibility or resistant to the EUS itself, although it was shown that the granulation rate and the level of

Disponibilidade aparente do fósforo em alimentos vegetais e suplementação da enzima fitase para tilápia-do-nilo Apparent phosphorus availability in vegetable feedstuffs and supplementation of phytase enzyme for Nile tilapia Oreochromis niloticus

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Giovani Sampaio Gonçalves

2007-10-01

Full Text Available Este estudo foi realizado com o objetivo de avaliar o efeito da fitase (0, 1.000 e 2.000 uf/kg na disponibilidade aparente de P de cinco alimentos energéticos (milho, milho extrusado, farelo de trigo, farelo de arroz e sorgo baixo tanino e cinco alimentos protéicos (soja extrusada, farelo de soja, farelo de girassol, farelo de algodão e glúten de milho utilizando-se uma ração purificada como controle. Foram utilizados 100 juvenis (100,00 ± 5,00 g de tilápia-do-nilo (Oreochromis niloticus alojados em dez gaiolas para manejo de alimentação e coleta de fezes. Para cada alimento e cada nível de fitase avaliado, foram coletadas amostras em cinco gaiolas, totalizando cinco repetições por tratamento. Os resultados obtidos indicaram que a suplementação de até 2.000 uf/kg de fitase não aumentou a disponibilidade aparente de P do farelo de trigo e do farelo de algodão. Entretanto, o nível de 1.000 uf/kg aumentou a disponibilidade aparente de P da soja extrusada e do farelo de girassol, enquanto o nível de 2.000 uf/kg proporcionou essa resposta para o farelo de milho, o milho extrusado, o sorgo baixo tanino, o farelo de arroz, o farelo de soja e o glúten de milho.This study was carried out to evaluate effects of phytase (0, 1,000, and 2,000 uf/kg on apparent P availability of five energetic feeds (corn, extruded corn, wheat meal, rice meal and low-tannin sorghum and five protein feeds (extruded soy, soybean meal, sunflower meal, cottonseed meal and corn gluten using a purified diet as control. One hundred (100.00 ± 5.00 g Nile tilapia juveniles (Oreochromis niloticus were allotted to ten cages to allow feeding and fecal collection. For each feed and each phytase level evaluated samples were collected from five cages, in a total of five replications per treatment. The obtained results showed that the phytase supplementation up to 2,000 uf/kg did not increase apparent P availability present in wheat meal or cottonseed meal. However, the

Tectus niloticus (Tegulidae, Gastropod) as a Novel Vector of Ciguatera Poisoning: Detection of Pacific Ciguatoxins in Toxic Samples from Nuku Hiva Island (French Polynesia).

Science.gov (United States)

Darius, Hélène Taiana; Roué, Mélanie; Sibat, Manoella; Viallon, Jérôme; Gatti, Clémence Mahana Iti; Vandersea, Mark W; Tester, Patricia A; Litaker, R Wayne; Amzil, Zouher; Hess, Philipp; Chinain, Mireille

2017-12-21

Ciguatera fish poisoning (CFP) is a foodborne disease caused by the consumption of seafood (fish and marine invertebrates) contaminated with ciguatoxins (CTXs) produced by dinoflagellates in the genus Gambierdiscus . The report of a CFP-like mass-poisoning outbreak following the consumption of Tectus niloticus (Tegulidae, Gastropod) from Anaho Bay on Nuku Hiva Island (Marquesas archipelago, French Polynesia) prompted field investigations to assess the presence of CTXs in T. niloticus . Samples were collected from Anaho Bay, 1, 6 and 28 months after this poisoning outbreak, as well as in Taiohae and Taipivai bays. Toxicity analysis using the neuroblastoma cell-based assay (CBA-N2a) detected the presence of CTXs only in Anaho Bay T. niloticus samples. This is consistent with qPCR results on window screen samples indicating the presence of Gambierdiscus communities dominated by the species G. polynesiensis in Anaho Bay. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) analyses revealed that P-CTX-3B was the major congener, followed by P-CTX-3C, P-CTX-4A and P-CTX-4B in toxic samples. Between July 2014 and November 2016, toxin content in T. niloticus progressively decreased, but was consistently above the safety limit recommended for human consumption. This study confirms for the first time T. niloticus as a novel vector of CFP in French Polynesia.

Tectus niloticus (Tegulidae, Gastropod as a Novel Vector of Ciguatera Poisoning: Detection of Pacific Ciguatoxins in Toxic Samples from Nuku Hiva Island (French Polynesia

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Hélène Taiana Darius

2017-12-01

Full Text Available Ciguatera fish poisoning (CFP is a foodborne disease caused by the consumption of seafood (fish and marine invertebrates contaminated with ciguatoxins (CTXs produced by dinoflagellates in the genus Gambierdiscus. The report of a CFP-like mass-poisoning outbreak following the consumption of Tectus niloticus (Tegulidae, Gastropod from Anaho Bay on Nuku Hiva Island (Marquesas archipelago, French Polynesia prompted field investigations to assess the presence of CTXs in T. niloticus. Samples were collected from Anaho Bay, 1, 6 and 28 months after this poisoning outbreak, as well as in Taiohae and Taipivai bays. Toxicity analysis using the neuroblastoma cell-based assay (CBA-N2a detected the presence of CTXs only in Anaho Bay T. niloticus samples. This is consistent with qPCR results on window screen samples indicating the presence of Gambierdiscus communities dominated by the species G. polynesiensis in Anaho Bay. Liquid chromatography-tandem mass spectrometry (LC-MS/MS analyses revealed that P-CTX-3B was the major congener, followed by P-CTX-3C, P-CTX-4A and P-CTX-4B in toxic samples. Between July 2014 and November 2016, toxin content in T. niloticus progressively decreased, but was consistently above the safety limit recommended for human consumption. This study confirms for the first time T. niloticus as a novel vector of CFP in French Polynesia.

Evaluation of Haematological and Biochemical Parameters of ...

African Journals Online (AJOL)

ADOWIE PERE

Evaluation of Haematological and Biochemical Parameters of Juvenile Oreochromis niloticus after Exposure to Water Soluble Fractions of ... niloticus were evaluated. After a preliminary determination of the 96 h-LC50 of ... evaporation, dissolution, emulsion, photolysis and biodegradation which generate a water soluble.

PCR en tiempo real para el sexaje y análisis citológico de la sinapsis del bivalente más pequeño en espermatocitos en paquiteno de Oreochromis niloticus

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Zulita Prieto

2017-01-01

Full Text Available El objetivo de la presente investigación fue dar a conocer nuevos marcadores moleculares para la PCR en tiempo real asociados a los cromosomas sexuales y el análisis de la sinapsis del bivalente más pequeño en espermatocitos en paquiteno de Oreochromis nil oticus . Se diseñaron cuatro pares de cebadores y se pusieron a prueba por PCR punto final y por PCR en tiempo real utilizando el fluorescente SYBR® Green en muestras de ADN de hembras XX, machos XY y supermachos YY. Los tamaños de los fragmentos amplificad os por PCR punto final fueron concordantes a los valores esperados y por PCR en tiempo real se demostró igual especificidad pero con ventaja en rapidez en la detección de amplificación de marcadores asociados a los cromosoma X y Y, de acuerdo con las condi ciones de la PCR establecidas. Las diferencias genéticas entre las regiones de los cromosomas X y Y demostradas con los marcadores específicos no fueron perceptibles citológicamente en los espermatocitos en paquiteno de O. niloticus XY. En base a las difer encias y homologías de las secuencias de ADN entre las accesiones KC710223 y KC710224 de los cromosomas X y Y se propone un modelo de sinapsis del bivalente XY.

Purificação, caracterização físico-química e atividade anticoagulante de glicosaminoglicanos isolados da pele de tilápia do Nilo (Oreochromis niloticus - doi: 10.4025/actascitechnol.v33i3.9400

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José Ariévilo Gurgel Rodrigues

2011-07-01

Full Text Available Os glicosaminoglicanos (GAGs constituem a matriz extracelular de tecidos animais e os resíduos do processamento de peixes comercialmente cultivados podem oferecer novos agentes anticoagulantes em substituição à heparina (HEP nas ciências médicas. Objetivou-se purificar, caracterizar físico-quimicamente e avaliar a atividade anticoagulante dos GAGs isolados da pele da tilápia do Nilo, Oreochromis niloticus. Os GAGs foram extraídos com papaína em tampão acetato de sódio 100 mM (pH 5,0 contendo cisteína e EDTA (5 mM, seguido por cromatografia de troca iônica em coluna de DEAE-celulose, utilizando um gradiente de NaCl. As frações obtidas foram liofilizadas e submetidas à eletroforese em gel de agarose a 0,5%. A atividade anticoagulante foi avaliada por meio do tempo de tromboplastina parcial ativada (TTPA, usando-se plasma humano normal e HEP padrão (193 UI mg-1. O perfil cromatográfico mostrou a separação de duas diferentes frações de GAGs (F I e F II, eluídas com 0,50 e 0,75 M de NaCl, respectivamente, revelando, por eletroforese, frações distintas em densidade de cargas, porém ambas mostrando GAGs com mobilidades semelhantes ao dermatam sulfato (DS padrão, sugerindo-se a identificação preliminar desse GAG. Os GAGs modificaram o TTPA, cujas atividades perfizeram, respectivamente, 4,72 (F I e 23,80 (F II UI mg-1, e expressaram-se dose-dependente. Portanto, o DS anticoagulante da pele de O. niloticus sugere uma fonte interessante para estudos posteriores de atividade antitrombótica.

Effects of artificial feeds on growth and production of fishes in Polyculture

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M.A. Hosen

2014-12-01

Full Text Available A study on the effects of artificial feeds on growth and production of fishes along with some limnological conditions were conducted in polyculture system. Species of Indian major carp (Cirrhinus mrigala and exotic fishes (Hypophthalmicthys molitrix and Oreochromis niloticus were stocked in six ponds under two treatments, each with three replications. Stocking rate in both treatments was 100 fish per decimal at the ratio of silver carp: tilapia: mrigal = 2: 2: 1. Fertilization and artificial feeds were given in Ttreatment 1 (T1 and only fertilization was done in Treatment 2 (T2. Wheat bran, rice bran and soybean meal were given daily as artificial feed in T1 in the ratio of wheat bran: rice bran: soybean meal = 2: 2: 1 (by wt. Urea, T.S.P and cow dung were applied fortnightly at the rate of 60 g deci-1, 90 g deci-1 and 2 kg deci-1 respectively. Water temperature, transparency, pH, dissolved oxygen, free CO2, total alkalinity, PO4-P and NO3-N were determined fortnightly and phytoplankton and zooplankton were studied fortnightly. These limnological conditions were more or less similar in the ponds under two treatments and were within suitable ranges. Calculated gross and net yields of fish were 16.56 and 12.48 ton ha-1 respectively in case of fertilization and artificial feeding application (T1 and 9.99 and 5.91 ton ha-1 respectively in case of only fertilization (T2. Application of artificial feed in T1 significantly increased the growth and production of fish more than two times which indicates that artificial feeding in polyculture is very useful for increasing fish production.

Oreochromis niloticus

African Journals Online (AJOL)

TUOYO

2010-08-09

Aug 9, 2010 ... dissolved oxygen, pH, visibility, TAN, nitrites and nitrates. The obtained data ... as a food for human. This industry is a key factor for increasing the economic ... using a digital balance OHAUS MODEL EC6, USA. Feed intake.

Oreochromis niloticus

African Journals Online (AJOL)

Yomi

2012-02-28

Feb 28, 2012 ... 2Nucleic Acids Research Department, Genetic Engineering and Biotechnology Research Institute (GEBRI), City for ... value of the Atlantic salmon catch is more than twice that .... related to dietary fat content, while the fatty acid.

Oreochromis niloticus

African Journals Online (AJOL)

USER

2015-06-01

Sayed, 1999). However, the use of soybean meal is limited because of the various uses to which it is put; as food for human being and ingredients for other livestock. The use of alternative plant protein sources which are.

Chromium oxide (51Cr2O3 used as biological marker was not absorbed by fish

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G.Z. Sakita

2015-06-01

Full Text Available The aim of this study was to evaluate the rate absorption of radio-labeled chromium oxide (51Cr2O3, used as biological marker in nutrition studies with Nile tilapia Oreochromis niloticus. An experimental diet with approximately 58 µCi of specific activity of the element was encapsulated and fed daily to 35 adult Nile tilapia; a group of 35 fish was used as control feeding on a basal diet. At the beginning of the experiment five fish from each group were randomly selected and blood samples were drawn from control (BC and experimental fish (BE. Fish were then euthanized by anesthetic overdoses and samples of the liver tissue (LT, renal tissue (RT, stomach without content (S, intestine without content (I, gills tissue (GT, muscle tissue (fillet; MT, visceral fat (VF, content of the digestive tract (CTDE and water aquarium were collected from the experimental fish. The procedure was repeated daily for one week. Simple linear regressions were adjusted - days of collection vs. determination coefficients, and were established for statistical comparisons of the measured activity of 51Cr readings in sampled blood and tissues (logarithmic transformation for samples of the control and experimental fish. No differences (P>0.05 were detected between samples from BC fish and BE, RT, VF, MT and LT of treated fish, but samples of GT, I, S, CTDE and WA from the tanks holding fish which received the experimental diet differed from control (P<0.05. The experimental results indicate that the trivalent chromium in the form of 51Cr2O3 was not significantly absorbed by the gastrointestinal tract, gills or another possible route of absorption under these experimental conditions and with Nile tilapia. Therefore, this marker was shown to be inert and can be safely used in nutrition studies.

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

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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