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.

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.

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

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.

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.

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

NARCIS (Netherlands)

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

2013-01-01

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

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.

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.

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.

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).

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

Science.gov (United States)

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.

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.

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

NARCIS (Netherlands)

El-Shafai, S.A.A.M.; El-Gohary, F.; Verreth, J.A.J.; Schrama, J.W.; Gijzen, H.J.

2004-01-01

Dry matter (DMD), protein (PD), ash (AD), fat (FD), gross energy (ED) and phosphorus (PhD) digestibility coefficients were determined for five different iso-N fish diets fed to Nile tilapia (Oreochromis niloticus). The control diet contained fishmeal (35%), corn (29%), wheat (20%), wheat bran (10%),

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...

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.

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.

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.

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.

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...

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

International Nuclear Information System (INIS)

Henry, L.; Kishimba, M.A.

2006-01-01

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 (α and β) 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

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

DEFF Research Database (Denmark)

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

2013-01-01

Fish-borne zoonotic trematode (FZT) infections affect the health of more than 18 million people around the world, particularly in Asian countries. Nile tilapia (Oreochromis niloticus) is a white meat fish that has an increasing national and international market. The objective of this study was to...... for vigilance and good management practices by the aquaculture sector. Crown...

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.

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.

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

DEFF Research Database (Denmark)

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

The fishborne zoonotic trematode parasites (FZT) which cause liver and intestinal infections in humans are widespread in fish in Southeast Asia. Guangdong Province is the most important region for tilapia (Oreochromis niloticus) culture in China, but it is also an endemic region for FZT. To assess...... the potential for FZT transmission in an area with high density of tilapia farms, wild-caught fish from local rivers and canals were bought at local markets. The wild-caught fish species included Hemiculter leucisculus (145), Rhodeus sinensis Gunther (10), Rasborinus lineatus (96), Squaliobarbus curriculus (6......), and Carassius auratus (4).The FZT species recovered were mainly Haplorchis taichui, and H. pumilio along with some unknown species whose identifications are still being determined. Subsequently a cross-sectional survey for the prevalence and diversity of FZT in tilapia culture systems was conducted in Guangdong...

Mixtures of diflubenzuron and p-chloroaniline changes the activities of enzymes biomarkers on tilapia fish (Oreochromis niloticus) in the presence and absence of soil.

Science.gov (United States)

Dantzger, Darlene D; Jonsson, Claudio M; Aoyama, Hiroshi

2018-02-01

The insecticide Diflubenzuron (DFB), used by many fish farming, when metabolized or degraded produces the extremely toxic compound p-chloroaniline (PCA). Once in the aquatic environment, these compounds can form mixtures and their bioavailability depends on factors such as the presence of soil. The toxic effects of the isolated compounds and their mixtures in the proportions: 75%, 50%, and 25% of PCA were analyzed in tilapia (Oreochromis niloticus) in the presence and absence of soil after 96h. The enzymes catalase (CAT), acid (AcP) and alkaline (AlP) phosphatases and alanine (ALT) and aspartate (AST) aminotransferases of the liver of the tilapia (Oreochromis niloticus) were used as biomarkers. DFB and the mixture containing 75% of this compound did not present high toxicity to fish; however, 25mg/L of PCA alone and 15mg/L of the mixture with 75% of this compound promoted 50% mortality of tilapia (Oreochromis niloticus). In the presence of soil, these toxicity values decreased to 37 and 25mg/L, respectively. Independent of the presence of soil, a synergistic effect was observed when the proportion of PCA was 75% and to the mixture, with 25% PCA was observed the antagonistic effect. Different concentrations of the compounds and their mixtures induced CAT activity independently of the presence of soil. Additionally, increases in phosphatases and transaminases activities were observed. In some cases, the enzymes also had their activities decreased and the dose-dependence effects were not observed. This research showed that the presence of soil influenced the toxicity of the compounds but not altered interaction type among them. Diflubenzuron, p-chloroaniline, and mixtures thereof caused disorders in enzymes important for the health of tilapia (Oreochromis niloticus). Copyright © 2017 Elsevier Inc. All rights reserved.

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

Science.gov (United States)

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.

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.

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.

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.

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

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

African Journals Online (AJOL)

******

2012-05-01

May 1, 2012 ... The same previous spawners of Nile tilapia, O. niloticus and Blue tilapia, O. aureus were used for full-sib of each of diallel interspecific hybridization fry production of ♀O. aureus x ♂ O. niloticus and ♀O. niloticus x ♂O. aureus. Water temperature was thermostatiscally regulated and fixed at 28°C.

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.

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

Science.gov (United States)

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

2009-04-01

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

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

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...

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

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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

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.

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)

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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.

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.

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

Science.gov (United States)

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 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

Science.gov (United States)

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.

Thermal preference predicts animal personality in Nile tilapia Oreochromis niloticus.

Science.gov (United States)

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

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.

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.

Identifications of Captive and Wild Tilapia Species Existing in Hawaii by Mitochondrial DNA Control Region Sequence

Science.gov (United States)

Wu, Liang; Yang, Jinzeng

2012-01-01

Background The tilapia family of the Cichlidae includes many fish species, which live in freshwater and saltwater environments. Several species, such as O. niloticus, O. aureus, and O. mossambicus, are excellent for aquaculture because these fish are easily reproduced and readily adapt to diverse environments. Historically, tilapia species, including O. mossambicus, S. melanotheron, and O. aureus, were introduced to Hawaii many decades ago, and the state of Hawaii uses the import permit policy to prevent O. niloticus from coming into the islands. However, hybrids produced from O. niloticus may already be present in the freshwater and marine environments of the islands. The purpose of this study was to identify tilapia species that exist in Hawaii using mitochondrial DNA analysis. Methodology/Principal Findings In this study, we analyzed 382 samples collected from 13 farm (captive) and wild tilapia populations in Oahu and the Hawaii Islands. Comparison of intraspecies variation between the mitochondrial DNA control region (mtDNA CR) and cytochrome c oxidase I (COI) gene from five populations indicated that mtDNA CR had higher nucleotide diversity than COI. A phylogenetic tree of all sampled tilapia was generated using mtDNA CR sequences. The neighbor-joining tree analysis identified seven distinctive tilapia species: O. aureus, O. mossambicus, O. niloticus, S. melanotheron, O. urolepies, T. redalli, and a hybrid of O. massambicus and O. niloticus. Of all the populations examined, 10 populations consisting of O. aureus, O. mossambicus, O. urolepis, and O. niloticus from the farmed sites were relatively pure, whereas three wild populations showed some degree of introgression and hybridization. Conclusions/Significance This DNA-based tilapia species identification is the first report that confirmed tilapia species identities in the wild and captive populations in Hawaii. The DNA sequence comparisons of mtDNA CR appear to be a valid method for tilapia species

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

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

Science.gov (United States)

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

2007-01-01

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

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

Directory of Open Access Journals (Sweden)

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.

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.

La pisciculture de Tilapia nilotica (= Sarotherodon niloticus dans les eaux continentales de Côte d'Ivoire

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Vincke, P.

1985-01-01

Full Text Available The fishculture of Tilapia niloiica (Sarotherodon niloticus in freshwater of Ivory Coast. In Ivory Coast, the freshwater fishculture in rural areas is mainly on a small scale. This type of breeding in ponds (2 to 4 ares yields on an average 3 metric tons of fish/ha/year and represents only an activity with self-consumption of products. The yield in intensive pond fishculture Tilapia nilotica is on an average 6 to 7 metric tons/ha/year but yields bigger than 10 metric tons/ha/year are not uncommon. The intensive fishculture in floating cages, requiring a minor investment but a more improved formation than in fischculture, yields on an average about 30 to 40 kg/m3/year. However the effective development of this activity rests on the resolution of problems like the sufficient fry production, the feeding and the commercialization.

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

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

Science.gov (United States)

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.

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.

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%.

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

Science.gov (United States)

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.

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...

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

Science.gov (United States)

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.

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.

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...

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.

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

DEFF Research Database (Denmark)

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...

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

Science.gov (United States)

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.

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.

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

Science.gov (United States)

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.

SNP marker detection and genotyping in tilapia

NARCIS (Netherlands)

Bers, van N.E.M.; Crooijmans, R.P.M.A.; Groenen, M.A.M.; Dibbits, B.W.; Komen, J.

2012-01-01

We have generated a unique resource consisting of nearly 175 000 short contig sequences and 3569 SNP markers from the widely cultured GIFT (Genetically Improved Farmed Tilapia) strain of Nile tilapia (Oreochromis niloticus). In total, 384 SNPs were selected to monitor the wider applicability of the

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.

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

OpenAIRE

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...

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

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

Science.gov (United States)

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...

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

Directory of Open Access Journals (Sweden)

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.

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

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

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

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.

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.

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

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

2017-01-01

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...

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.

[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.

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

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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.

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

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.

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.

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.

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

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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.

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

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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.

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

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.

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

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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.

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

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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.

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

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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.

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.

Molecular cloning, functional identification and expressional analyses of FasL in Tilapia, Oreochromis niloticus.

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Ma, Tai-yang; Wu, Jin-ying; Gao, Xiao-ke; Wang, Jing-yuan; Zhan, Xu-liang; Li, Wen-sheng

2014-10-01

FasL is the most extensively studied apoptosis ligand. In 2000, tilapia FasL was identified using anti-human FasL monoclonal antibody by Evans's research group. Recently, a tilapia FasL-like protein of smaller molecule weight was predicted in Genbank (XM_003445156.2). Based on several clues drawn from previous studies, we cast doubt on the authenticity of the formerly identified tilapia FasL. Conversely, using reverse transcription polymerase chain reaction (RT-PCR), the existence of the predicted FasL-like was verified at the mRNA level (The Genbank accession number of the FasL mRNA sequence we cloned is KM008610). Through multiple alignments, this FasL-like protein was found to be highly similar to the FasL of the Japanese flounder. Moreover, we artificially expressed the functional region of the predicted protein and later confirmed its apoptosis-inducing activity using a methyl thiazolyl tetrazolium (MTT) assay, Annexin-V/Propidium iodide (PI) double staining, and DNA fragment detection. Supported by these evidences, we suggest that the predicted protein is the authentic tilapia FasL. To advance this research further, tilapia FasL mRNA and its protein across different tissues were quantified. High expression levels were identified in the tilapia immune system and sites where active cell turnover conservatively occurs. In this regard, FasL may assume an active role in the immune system and cell homeostasis maintenance in tilapia, similar to that shown in other species. In addition, because the distribution pattern of FasL mRNA did not synchronize with that of the protein, post-transcriptional expression regulation is suggested. Such regulation may be dominated by potential adenylate- and uridylate-rich elements (AREs) featuring AUUUA repeats found in the 3' untranslated region (UTR) of tilapia FasL mRNA. Copyright © 2014 Elsevier Ltd. All rights reserved.

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%.

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

Science.gov (United States)

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.

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...

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

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)

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.

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.

Development of Streptococcus agalactiae vaccines for tilapia.

Science.gov (United States)

Liu, Guangjin; Zhu, Jielian; Chen, Kangming; Gao, Tingting; Yao, Huochun; Liu, Yongjie; Zhang, Wei; Lu, Chengping

2016-12-21

Vaccination is a widely accepted and effective method to prevent most pathogenic diseases in aquaculture. Various species of tilapia, especially Nile tilapia Oreochromis niloticus, are farmed worldwide because of their high consumer demand. Recently, the tilapia-breeding industry has been hampered by outbreaks of Streptococcus agalactiae infection, which cause high mortality and huge economic losses. Many researchers have attempted to develop effective S. agalactiae vaccines for tilapia. This review provides a summary of the different kinds of S. agalactiae vaccines for tilapia that have been developed recently. Among the various vaccine types, inactivated S. agalactiae vaccines showed superior protection efficiency when compared with live attenuated, recombinant and DNA vaccines. With respect to vaccination method, injecting the vaccine into tilapia provided the most effective immunoprotection. Freund's incomplete adjuvant appeared to be suitable for tilapia vaccines. Other factors, such as immunization duration and number, fish size and challenge dose, also influenced the vaccine efficacy.

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.

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.

Differences in sexual size dimorphism among farmed tilapia species and strains undergoing genetic improvement for body weight

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C.E. Lind

2015-05-01

Full Text Available Many tilapia (Oreochromis spp. farmers produce all-male populations because of the superior growth rate of males compared to females. To investigate differences in body weight at harvest of males and females among different tilapia strains, we analyzed data from 62,787 individuals collected from pedigreed breeding programs of O. niloticus (GIFT from Malaysia, the Abbassa line from Egypt, and the Akosombo line from Ghana, O. shiranus (the Bunda College-Domasi selection line, O. aureus (a selection line under development in Abbassa, Egypt, and a selection line from Israel and a synthetic selection line of Red tilapia under development in Jitra, Malaysia, derived from stock from Malaysia, Taiwan and Thailand (O. sp.. Mixed models were separately fitted to the data from each selection line. There was a significant sex effect in all strains (P < 0.001. A significant (P < 0.001 sex by generation interaction was observed in all strains (scale effect, not reversal of rankings, except Red tilapia and O. shiranus. Least squares means showed a large range in the magnitude of body weight differences between sexes across the seven strains. The largest percentage difference between females and males was in O. aureus from Egypt (female body weight was 52.2% that of males at harvest, whereas the smallest difference was observed in the GIFT strain of O. niloticus (female body weight 84.7% that of males. Female to male body weight percentages for Red tilapia, O. shiranus, Egypt O. niloticus, Israeli O. aureus and Ghana O. niloticus were 81.3, 81.0, 69.1, 61.7 and 61.0, respectively. We discuss the results in relation to the potential productivity improvements due to superior growth rates of all-male culture compared to mixed-sex culture in tilapia populations differing in the female to male body weight ratio.

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

African Journals Online (AJOL)

ACSS

tilapia (Oreochromis niloticus) stocks in lakes Albert, Edward and George, as well as in Albert Nile. River ... multivariate approaches including principal component analysis, ... Along the way, many private ... and selection for the best performing.

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)

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

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

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

Directory of Open Access Journals (Sweden)

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

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.

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.

Production of Genetically Improved Organic Nile Tilapia

NARCIS (Netherlands)

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

2008-01-01

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

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)

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...

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.

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 ...

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

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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.

A Survey of Nematode Infection in Oreochromis niloticus (L ...

African Journals Online (AJOL)

The incidence and intensity of nematode infection was investigated in Nile tilapia Oreochromis niloticus from Lake Kyoga, Uganda and 11% of the 406 fish examined were parasitized by nematodes of the genus Contracaecum. The prevalence of these parasites was greatest in the smallest and largest size classes, but this ...

Sundried Cassava Leaf Meal as Protein Source for Nile Tilapia

African Journals Online (AJOL)

(Ng and Wee, 1989), low digestibility in Asian sea bass, Lates ... Source for Nile Tilapia Oreochromis niloticus (L) Juvenile's Diet. *Madalla1, N. ... growth, nutrient utilisation and whole body composition after an eight week growth trial. SGR.

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

Science.gov (United States)

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.

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.

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.

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.

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.

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.

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...

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

Science.gov (United States)

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

2017-08-01

The aim of present study was determination effects of dietary administration of C. militaris spent mushroom substrate (SMS) on mucosal and serum immune parameters, disease resistance, and growth performance of Nile tilapia (Oreochromis niloticus). Two hundred twenty five fish of similar weight (37.28 ± 0.10 g) were assigned to the following diets [0 (T1- Control), 5 (T2), 10 (T3), 20 (T4) and 40 g kg -1 (T5) SMS]. After 60 days of feeding trial, growth performance, skin mucus lysozyme and peroxidase activities as well as serum innate immune were measured. In addition, survival rate and innate immune responses were calculated after challenge test (15 days) against Streptococcus agalactiae. The results revealed that regardless of inclusion levels, feeding Nile tilapia with SMS supplemented diets significantly increased skin mucus lysozyme and peroxidase activities as well as serum immune parameters (SL, ACH50, PI, RB, and RB) compared control group (P health status. Copyright © 2017 Elsevier Ltd. All rights reserved.

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)

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.

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.

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)

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

Science.gov (United States)

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

2016-02-01

Interferon regulatory factor 3 (IRF3) plays a key role in interferon (IFN) response and binding to the IFN stimulatory response elements (ISREs) within the promoter of IFN and IFN-stimulated genes followed by virus infection. In the current study, we discovered one IRF3 homologue in tilapia genome and analyzed the characterizations and functions of tilapia IRF3. Tilapia IRF3 contains 1368 bp with an ORF of 455 aa. Structurally, tilapia IRF3 protein typically shares the conserved characterizations with other species' IRF3 homologues, displaying conserved DNA-binding domain, IRF association domain, serine-rich C terminal domain, and tryptophan residue cluster. Phylogenetic analysis illustrated that tilapia IRF3 belongs to the IRF3 subfamily. Real-time PCR revealed a broad expression pattern of tilapia IRF3 in various tissues. Subcellular localization analysis showed that tilapia IRF3 mainly resides in the cytoplasm, Western blot demonstrated that IRF3 was distributed in the cytoplasmic fraction. Functionally, IRF3 was found to be transcriptionally up-regulated by the poly I:C stimulation. Moreover, reporter assay elucidated that tilapia IRF3 serves as a regulator in mediating IFN response by increasing the activity of IFN-β and ISRE-containing promoter. These data supported the view that tilapia IRF3 is a potential molecule in IFN immune defense system against viral infection. Copyright © 2015 Elsevier Ltd. All rights reserved.

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

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.

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

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

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 ...

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.

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.

FEEDING FREQUENCY OF NILE TILAPIA FED RATIONS SUPPLEMENTED WITH AMINO ACIDS

OpenAIRE

EDUARDO ARRUDA TEIXEIRA LANNA; MARCOS ANTONIO DELMONDES BOMFIM; FELIPE BARBOSA RIBEIRO; MOISÉS QUADROS

2016-01-01

The present study evaluated the feeding frequency of Nile tilapia (Oreochromis niloticus) fed low-protein diets (29% crude protein) supplemented with commercial amino acids (L-lysine-HCl, DL-methionine, and L-threonine). Sex-reversed Nile tilapia (240) of Thai origin, with initial body weight of 0.93 ± 0.03 g each, were allocated in a completely randomized design, to five groups with various feeding frequencies (2, 3, 4, 5, and 6 times a day). Six replications were conducted on separate exper...

FEEDING FREQUENCY OF NILE TILAPIA FED RATIONS SUPPLEMENTED WITH AMINO ACIDS

OpenAIRE

LANNA, EDUARDO ARRUDA TEIXEIRA; BOMFIM, MARCOS ANTONIO DELMONDES; RIBEIRO, FELIPE BARBOSA; QUADROS, MOISÉS

2016-01-01

ABSTRACT: The present study evaluated the feeding frequency of Nile tilapia (Oreochromis niloticus) fed low-protein diets (29% crude protein) supplemented with commercial amino acids (L-lysine-HCl, DL-methionine, and L-threonine). Sex-reversed Nile tilapia (240) of Thai origin, with initial body weight of 0.93 ± 0.03 g each, were allocated in a completely randomized design, to five groups with various feeding frequencies (2, 3, 4, 5, and 6 times a day). Six replications were conducted on sepa...

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 ...

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...

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.

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.

Stomach Length and Food Preference of three Tilapia species ...

African Journals Online (AJOL)

Results showed that T . zillii was herbivorous while T . mariae and O. niloticus subsisted mainly on a wide variety of plankton. Generally, considerable quantities of zoo – and phyto-plankton were present in the food of the three species. Variations were observed in the gut lengths and dental anatomy of the tilapias which ...

Daily growth of young-of-the-year of the Baringo tilapia ...

African Journals Online (AJOL)

Otolith microstructure analysis was used to validate microincrement deposition rate and to determine daily growth rates of young-of-the-year (YOY) Baringo tilapia, Oreochromis niloticus baringoensis. Microincrement formation was validated as daily by correlating the number of circuli on otoliths with the known age of ...

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.

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

Science.gov (United States)

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

2012-09-01

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

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.

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

African Journals Online (AJOL)

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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 ,.

Intensive aquaculture of tilapia (Sarotherodon niloticus) in the thermal effluents of a nuclear power plant in Belgium

International Nuclear Information System (INIS)

Melard, Ch.; Philippart, J.C.

1981-01-01

This paper presents the results of three years of experiments in cultivating S. niloticus in the cooling waters of the nuclear power station at Tihange on the Meuse. The research station infrastructure consists of three earthen ponds measuring 150m 2 (volume: 200m 3 ) and 16 fibreglass tanks of 4m 2 (2m 3 ). These are fed by a pumping system (70m 3 /h) at the outlet point of the power station condenser. A regulation system ensures that the feed-water is kept at a safe thermal level (17-32 deg. C). The Meuse has a high biological productivity potential at Tihange; there is no chemical pollution of any significance, although moderate organic pollution exists. The thermal conditions in the river make it possible to count on nine months (March to December) during which the average utilizable water temperature for tilapia culture exceeds 20 deg. C. Under conditions of intensive-tank culture, it was possible to maintain a maximum biomass (with 150g fish) of 120kg/m 3 of tank with a water renewal rate of about 3.5 times per hour (loading: 2.1kg/liter per minute). A figure is provided showing the relation to weight of oxygen consumption and optimal loading at a temperature of 30-32 deg. C. The highest yields recorded are 21.1q/m 3 per hour and 25.7kg/m 3 of tank/month; with an average yield of 12g/m 3 per hour, a volume of 85m 3 of heated water is required to produce 1kg of S. niloticus from 20g of male fry. The fish are suitable for marketing (trial offer to restaurants) if they weigh 300-350g. Analysis shows that their heavy metals and radionuclide content is below the level permitted by law. (author)

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

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

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

DEFF Research Database (Denmark)

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

2015-01-01

Two case studies from Southeast Asia are used to analyse production, environmental effects, and economic optimisation of Nile tilapia (Oreochromis niloticus) and white shrimp (Penaeus vannamei) pond culture. A projection of these data is made for the whole of Thailand. The results are analysed...... on a regional scale based on site selection using multi-criteria evaluation (MCE). Farm-scale culture was simulated for (i) tilapia monoculture in Chiang Rai; (ii) shrimp monoculture in Chanthaburi; and (iii) Integrated Multi-Trophic Aquaculture (IMTA) of tilapia and shrimp in Chon Buri. Together...... in ponds. Co-cultivation stimulates nitrogen dissolution (134 kg N cycle− 1), which is greater than in tilapia (96 kg N) or shrimp (52 kg N) monoculture, and doubles the NH4+ discharge to the environment (10.7 kg in tilapia monoculture, 20.5 kg in co-cultivation). However, eutrophication as a result...

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.

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

Science.gov (United States)

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.

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

Science.gov (United States)

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.

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

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

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.

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

2014-01-01

Full Text Available 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 aleatoria en 48 acuarios de vidrio (80 l, 4 réplicas, 7 peces por acuario. No se detectó selenio en el agua de abastecimiento. Los peces fueron alimentados hasta saciedad aparente 3 veces al día por un período de 9 semanas. El desempeño productivo de la tilapia nilótica no se vio afectado ( P >0.05 por la suplementación con selenio dietario. El selenio corporal se incrementó de forma lineal ( P <0.05 con la suplementación de selenio orgánico e inorgánico. La composición corporal de selenio fue menor ( P <0.05 en los peces suplementados con selenito de sodio (1.67±0.14 mg/kg en comparación con la seleno-levadura (1.95±0.21 mg/kg. A partir de la relación entre pendientes se estimó que la biodisponibilidad relativa de la seleno- levadura para la composición de selenio corporal fue de 155.72±0,10%, con relación al selenito de sodio (fijada en 100%. De acuerdo con los resultados, la concentración basal de selenio dietario (0.21 mg/kg no limitó el desempeño productivo de tilapia nilótica. La suplementación con selenio orgánico (seleno-levadura e inorgánico (selenito de sodio entre 0.10 y 1.60 mg/kg no afectó el desempeño productivo de la tilapia nilótica.

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.

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...

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

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.

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.

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 ...

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.

A humane protocol for electro-stunning and killing of Nile tilapia in fresh water

NARCIS (Netherlands)

Lambooij, E.; Gerritzen, M.A.; Reimert, H.G.M.; Burggraaf, D.; Vis, van de J.W.

2008-01-01

Behavioural, neural and physiological parameters were scored after electro-stunning of Nile tilapia (Oreochromis niloticus) in three positions to an electric field in fresh water. An overall current density, 1.0 Arms/dm2, 50 Hz sinusoidal, applied for 1 s top-to-bottom in water (700 ¿S/cm), induced

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.

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

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.

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

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.

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

Science.gov (United States)

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.

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

Science.gov (United States)

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

Effect of constant digestible protein intake and varying digestible energy levels on energy and protein utilization in Nile tilapia

NARCIS (Netherlands)

Haidar, M.N.; Bleeker, S.; Heinsbroek, L.T.N.; Schrama, J.W.

2018-01-01

In literature, the variability in the estimated optimal digestible protein to digestible energy ratio (DP/DE) is high. The present study aimed to estimate the optimal DP/DE ratio in Nile tilapia (Oreochromis niloticus) using different criteria (performance, energy and nitrogen balances parameters).

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

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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.

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

Science.gov (United States)

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

2014-01-01

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

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.

MicroRNA repertoire for functional genome research in tilapia identified by deep sequencing.

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Yan, Biao; Wang, Zhen-Hua; Zhu, Chang-Dong; Guo, Jin-Tao; Zhao, Jin-Liang

2014-08-01

The Nile tilapia (Oreochromis niloticus; Cichlidae) is an economically important species in aquaculture and occupies a prominent position in the aquaculture industry. MicroRNAs (miRNAs) are a class of noncoding RNAs that post-transcriptionally regulate gene expression involved in diverse biological and metabolic processes. To increase the repertoire of miRNAs characterized in tilapia, we used the Illumina/Solexa sequencing technology to sequence a small RNA library using pooled RNA sample isolated from the different developmental stages of tilapia. Bioinformatic analyses suggest that 197 conserved and 27 novel miRNAs are expressed in tilapia. Sequence alignments indicate that all tested miRNAs and miRNAs* are highly conserved across many species. In addition, we characterized the tissue expression patterns of five miRNAs using real-time quantitative PCR. We found that miR-1/206, miR-7/9, and miR-122 is abundantly expressed in muscle, brain, and liver, respectively, implying a potential role in the regulation of tissue differentiation or the maintenance of tissue identity. Overall, our results expand the number of tilapia miRNAs, and the discovery of miRNAs in tilapia genome contributes to a better understanding the role of miRNAs in regulating diverse biological processes.

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.

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.

Inactivation kinetics of formaldehyde on N-acetyl-β-D-glucosaminidase from Nile tilapia (Oreochromis niloticus).

Science.gov (United States)

Zhang, Wei-Ni; Bai, Ding-Ping; Lin, Xin-Yu; Chen, Qing-Xi; Huang, Xiao-Hong; Huang, Yi-Fan

2014-04-01

Formaldehyde is a widely used sanitizer in aquaculture in China, while the appropriate concentration is not available to be used effectively and without damage to tilapia much less to its reproductive function. N-acetyl-β-D-glucosaminidase (EC 3.2.1.52, NAGase), hydrolyzing the oligomers of N-acetyl-β-D-glucosamine into monomer, is proved to be correlated with reproduction of male animals. In this paper, NAGase from spermary of tilapia was chosen as the material to study the effects of formaldehyde on its activity in order to further investigate the effects of formaldehyde use on tilapia reproduction. The results showed the relationship between the residual enzyme activity and the concentration of formaldehyde was concentration dependent, and the IC50 value was estimated to be 3.2 ± 0.1 %. Appropriate concentration of formaldehyde leaded to competitive reversible inhibition on tilapia NAGase. Moreover, formaldehyde could reduce the thermal and pH stability of the enzyme. The inactivation kinetics of formaldehyde on the enzyme was studied using the kinetic method of substrate reaction. The inactivation model was setup, and the rate constants were determined. The results showed that the inactivation of formaldehyde on tilapia NAGase was a slow, reversible reaction with partially residual activity. The results will give some basis to determine the concentration of formaldehyde used in tilapia culture.

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

OpenAIRE

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...

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.

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

NARCIS (Netherlands)

Rutten, M.J.M.

2005-01-01

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

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

Science.gov (United States)

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.

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

NARCIS (Netherlands)

Trong, T.Q.

2013-01-01

The aim of this thesis was to optimise the selective breeding program for Nile tilapia in the Mekong Delta region of Vietnam. Two breeding schemes, the “classic” BLUP scheme following the GIFT method (with pair mating) and a rotational mating scheme with own performance selection and

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.

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.

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

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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.

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.

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.

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.

Quality properties, fatty acids, and biogenic amines profile of fresh tilapia stored in ice.

Science.gov (United States)

Kulawik, Piotr; Özoğul, Fatih; Glew, Robert H

2013-07-01

This work determines quality properties and fatty acids content of Nile tilapia (Oreochromis niloticus) stored in ice for 21 d. The quality properties consist of thiobarbituic acid (TBA), total volatile basic nitrogen (TVB-N), trimethylamine (TMA), and microbiological analysis (total viable count (TVC), total coliform, Salmonella and Staphylococcus aureus) and determination of biogenic amines content (histamine, cadaverine, putrescine, spermine, spermidine, 2-phenylethylamine, agmatine, tyramine, and ammonia). Moreover, the fat, moisture, and ash composition as well as fatty acids profile have also been analyzed. The TBA, TVB-N, and biogenic amines analysis showed rather low levels of spoilage even after 21 d of storage. The microbiological analysis, however, showed that tilapia was unsuitable for consumption after just 10 d. The fat, ash, moisture, and fatty acids profile analysis showed that tilapia is not a good source of n-3 fatty acids. The research indicated that the microbiological analysis was the best method to establish spoilage of tilapia stored in ice, of all analytical methods performed in this study. © 2013 Institute of Food Technologists®

Isolation and Pathogenicity of Streptococcus iniae in Cultured Red Hybrid Tilapia in Malaysia.

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Rahmatullah, M; Ariff, M; Kahieshesfandiari, M; Daud, H M; Zamri-Saad, M; Sabri, M Y; Amal, M N A; Ina-Salwany, M Y

2017-12-01

This study describes the isolation and pathogenicity of Streptococcus iniae in cultured red hybrid tilapia (Nile Tilapia Oreochromis niloticus × Mozambique Tilapia O. mossambicus) in Malaysia. The isolated gram-positive S. iniae appeared punctiform, transparently white, catalase and oxidase negative and produced complete β-hemolysis on blood agar, while a PCR assay resulted in the amplification of the 16 S rRNA gene and lactate oxidase encoded genes. The isolate was sensitive to tetracycline, vancomycin, and bacitracin but was resistant to streptomycin, ampicillin, penicillin, and erythromycin. Pathogenicity trials conducted in local red hybrid tilapia (mean ± SE = 20.00 ± 0.45 g) showed 90.0, 96.7, and 100.0% mortality within 14 d postinfection following intraperitoneal exposure to 10 4 , 10 6 , and 10 8 CFU/mL of the pathogen, respectively. The clinical signs included erratic swimming, lethargy, and inappetance at 6 h postinfection, while mortality was recorded at less than 24 h postinfection in all infected groups. The LD 50-336 h of S. iniae against the red hybrid tilapia was 10 2 CFU/mL. The post mortem examinations revealed congested livers, kidneys, and spleens of the infected fish. This is the first report of S. iniae experimental infection in cultured red hybrid tilapia in Malaysia. Received January 20, 2017; accepted July 16, 2017.

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.

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.

La Tilapia en el Perú: acuicultura, mercado, y perspectivas

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Paúl M. Baltazar

2013-05-01

Full Text Available Tilapia es el nombre común con el cual se conocen a diversas especies de los géneros Oreochromis y Tilapia. Las Tilapias son peces de agua dulce endémicos y originarios de África y el Cercano Oriente, aprovechando sus características y adaptabilidad, a comienzos del siglo XIX se inician las investigaciones para utilizarlas en la piscicultura rural, especialmente en el Congo Belga (actualmente Zaire. A partir de 1924 se intensifica su cultivo en Kenia, sin embargo fue en el Extremo Oriente, en Malasia en donde se obtuvieron los mejores resultados y se iniciara su progresivo cultivo en diferentes partes del mundo. En Perú, en la década del 50, la Dirección General de Caza y Pesca del Ministerio de Fomento y Agricultura realizó las primeras introducciones con la especie Tilapia rendalli, utilizada como forraje para el paiche (Arapaina gigas; en la década de los 70, el IMARPE y la Universidad Nacional Agraria La Molina introdujeron las especies Oreochromis niloticus, Oreochromis hornorum y Oreochromis mossambica (Ramos y Gálvez, 2000, con fines de investigación y cultivo en las zonas de selva. La Tilapia roja, Oreochromis spp., ingresa a nuestro país entre los meses de octubre y noviembre de 1996, como parte complementaria de otro lote de reproductores grises, (con el objetivo de evitar la endogamia, procedentes de la Estación DIVISA, Panamá.

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.

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

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.

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.

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

Influence of glyceryl guaiacolate ether on anesthetics in tilapia compared to benzocaine and eugenol

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Geovana R. Cosenza

2014-03-01

Full Text Available Objective. The study aimed to investigate the effectiveness of glyceryl guaiacolate ether (GGE and compare the times of induction, recovery, hematological changes, total protein and glycaemia among anesthetics in Nile tilapia, Oreochromis niloticus. Materials and methods. A total of 60 tilapia distributed in 3 aquariums (N=20 were used, which formed the group benzocaine (100 mg/L, eugenol (50 mg/L and guaiacol glyceryl ether (9.000 mg/L. After the induction of anesthesia fish blood samples were collected to determine the complete hemogram and glycemia. Then the animals were placed in aquariums with running water for assessing the anesthesia recovery. Results. It was verified that GGE showed longer induction and recovery times as well a significant increase (p0.05. An increase in the number of monocytes in the group treated with benzocaine (p <0.05 was observed in the analysis of the hematological parameters with no difference between groups for other variables. Conclusions. Eugenol and benzocaine allow rapid induction and recovery in Nile tilapia, without evidence of stress during handling and GGE showed high induction and recovery times, being inadequate for anesthetic use in Nile tilapia.

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

Science.gov (United States)

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

Modelling of fillet traits based on body measurements in three Nile tilapia strains (Oreochromis niloticus L.)

NARCIS (Netherlands)

Rutten, M.J.M.; Bovenhuis, H.; Komen, J.

2004-01-01

In Nile tilapia, breeding programs focus mainly on growth, and information on genetic improvement of fillet yield is scarce. In this study, slaughter data were collected on 1215 tilapia and used to analyze the relationship between body measurements and fillet weight and fillet yield. Fish were

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.

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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.

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

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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

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.

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

OpenAIRE

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...

Agroindustrial byproducts in diets for Nile tilapia juveniles

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João Sérgio Oliveira Carvalho

2012-03-01

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

Molecular cloning and gene expression of Foxl2 in the Nile tilapia, Oreochromis niloticus

International Nuclear Information System (INIS)

Wang Deshou; Kobayashi, Tohru; Zhou Linyan; Nagahama, Yoshitaka

2004-01-01

A Foxl2 cDNA was cloned from the Nile tilapia ovary by RT-PCR and subsequent RACE. Alignment of known Foxl2 sequences from vertebrates confirmed the conservation of the Foxl2 open reading frame and protein sequences, especially the forkhead domain and C-terminal region, while some homopolymeric runs of amino acids are found only in mammals but not in non-mammalian vertebrates. RT-PCR revealed that Foxl2 is expressed in the tilapia brain (B), pituitary (P), gill, and gonads (G), with the highest level of expression in the ovary, reflecting the involvement of Foxl2 in B-P-G axis. Northern blotting and in situ hybridization also revealed an evident sexual dimorphic expression pattern in the gonads. Foxl2 mRNA was mainly detected in the granulosa cells surrounding the oocytes. The ovarian expression of Foxl2 in tilapia begins early during the differentiation of the gonads and persists until adulthood, implying the involvement of Foxl2 in fish gonad differentiation and the maintenance of ovarian function

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.

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.

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.

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.

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.

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

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

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.

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.

Polyculture Engineering technology of larasati red tilapia (Oreochromis niloticus) and white shrimp (Litopenaeus vannamei) based for protease enzyme

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Samidjan, I.; Rachmawati, D.

2018-04-01

The objective is polyculture technology of red tilapia larasati fish and white shrimp with different combinations density. The material is saline red tilapia larasati 3.29 ± 0.018 g and white shrimp with initial weight 1.39 ± 0.025 g. Seeds are density of red tilapia larasati larvae 5 and 10 larvae / m2 fish. And white shrimp 5 larvae / m2 and 10 larvae / m2. An artificial feed used enzyme dose of 2.25 g / kg. The experimental using complete randomized design 4 treatments and 3 replications that is given seeds 5 larvae / m2 larvae red tilapia larasati and given 5 larvae / m2 white shrimp (A), 5 larvae / m2 red tilapia) and 10 m2 / m2 of white shrimp (B), 10 m2 larvae and 5 m2 white shrimp (C), 10 m2 larvae and 10 m2 white shrimp (D)). The data were growth of absolute weight, survival rate, FCR, and water quality data (temperature, salinity, pH, O2, NO2, NH3). Data were analyzed of variance (F test). The results showed significantly effect (P shrimp (25.25 ± 0.95 g).

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

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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.

Proyecto de diseño de industria de procesado y exportación de tilapia y definición tipo de la obra civil e instalaciones en Huila (Colombia)

OpenAIRE

Contín Vital, Javier

2015-01-01

El presente Trabajo Fin de Grado (TFG) titulado “Diseño de industria de procesado y exportación de tilapia y definición tipo de la obra civil e instalaciones en Huila (Colombia)” tiene como objeto, el diseño de una industria de procesado de tilapia nilótica (Oreochromis niloticus) en fresco, como filete y pescado entero, y en congelado, como entero, para una capacidad de producción aproximada de 960 toneladas mensuales en el Departamento del Huila. Desarrollado con la estructur...

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

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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...

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

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

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.

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.

Manejo de cocodrilos (Crocodylus acutus) en estanques de cultivo de tilapia en Cañas, Guanacaste

OpenAIRE

Bolaños, Juan Rafael

2012-01-01

En la cuenca baja del Tempisque se han incrementado los avistamientos de cocodrilos (Crocodylus acutus) en cuerpos de agua naturales y artificiales. Este trabajo describe un plan implementado para operacionalizar el control de cocodrilos en estanques con cultivo de tilapia (Oreochromis niloticus). De acuerdo con él se redujo el consumo de producto por parte de cocodrilos y se potenció la seguridad de los trabajadores en esos estanques. Durante seis años de actividad, el plan evolucionó desde ...

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)

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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.

Colorimetric Method of Loop-Mediated Isothermal Amplification with the Pre-Addition of Calcein for Detecting Flavobacterium columnare and its Assessment in Tilapia Farms.

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Suebsing, Rungkarn; Kampeera, Jantana; Sirithammajak, Sarawut; Withyachumnarnkul, Boonsirm; Turner, Warren; Kiatpathomchai, Wansika

2015-03-01

Flavobacterium columnare, the causative agent of columnaris disease in fish, affects many economically important freshwater fish species. A colorimetric method of loop-mediated isothermal amplification with the pre-addition of calcein (LAMP-calcein) was developed and used to detect the presence of F. columnare in farmed tilapia (Nile Tilapia Oreochromis niloticus and red tilapia [Nile Tilapia × Mozambique Tilapia O. mossambicus]) and rearing water. The detection method, based on a change in color from orange to green, could be performed within 45 min at 63°C. The method was highly specific, as it had no cross-detections with 14 other bacterial species, including other fish pathogens and two Flavobacterium species. The method has a minimum detection limit of 2.2 × 10(2) F. columnare CFU; thus, it is about 10 times more sensitive than conventional PCR. With this method, F. columnare was detected in gonad, gill, and blood samples from apparently healthy tilapia broodstock as well as in samples of fertilized eggs, newly hatched fry, and rearing water. The bacteria isolated from the blood were further characterized biochemically and found to be phenotypically identical to F. columnare. The amplified products from the LAMP-calcein method had 97% homology with the DNA sequence of F. columnare.

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-.

GapA, a potential vaccine candidate antigen against Streptococcus agalactiae in Nile tilapia (Oreochromis niloticus).

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Zhang, Ze; Yu, Angen; Lan, Jiangfeng; Zhang, Hua; Hu, Minqiang; Cheng, Jiewei; Zhao, Lijuan; Lin, Li; Wei, Shun

2017-04-01

Streptococcosis due to the bacterium Streptococcus agalactiae (S. agalactiae) has resulted in enormous economic losses in aquaculture worldwide, especially in the tilapia culture industry. Previously, there were limited vaccines that could be employed against streptococcosis in tilapia. This study aimed to develop a vaccine candidate using the glyceraldehyde-phosphate dehydrogenase protein (GapA) of S. agalactiae encoded by the gapA gene. Tilapia were intraperitoneally injected with PBS, PBS + Freund's adjuvant, PBS + Montanide's adjuvant, GapA + Freund's adjuvant, GapA + Montanide's adjuvant, killed S. agalactiae whole cells (WC)+Freund's adjuvant, or killed S. agalactiae whole cells (WC)+ Montanide's adjuvant. They were then challenged with S. agalactiae, and the relative percentage survival (RPS) was monitored 14 days after the challenge. The highest RPSs were observed in the WC groups, with 76.7% in WC + Freund's adjuvant and 74.4% in WC + Montanide's adjuvant groups; these were followed by the GapA groups, with 63.3% in GapA + Freund's adjuvant and 45.6% in GapA + Montanide's adjuvant groups. The RPS of the PBS group was 0%, and those of PBS + Freund's adjuvant and PBS + Montanide's adjuvant groups were 6.7% and 3.3%, respectively. Additionally, the IgM antibody responses elicited in GapA groups and WC groups were significantly higher than those in PBS groups. Furthermore, the expressions of cytokine (IL-1β and TNF-α) mRNAs in the GapA groups and WC groups were significantly higher than those in the PBS groups. Taken together, these results reveal that the GapA protein is a promising vaccine candidate that could be used to prevent streptococcosis in tilapia. Copyright © 2017 Elsevier Ltd. All rights reserved.

Masculinization of nile tilapia (Oreochromis niloticus) using extract of bull testes

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Yustiati, A.; Bangkit, I.; Zidni, I.

2018-03-01

Tilapia males grow faster to increase the production of the fish, there is a necessity to produce all males by using extract of bull testes. The research method used in this study was the experimental Completely Randomized Design (CRD) with five treatments and three replications. The treatments were A: without immersion and without oral treatment (control); B; immersion 600 μg·L-1 without oral treatment; C: immersion 600 μg·L-1 and oral at a dose of 30 mg·kg-1 feeds, D: immersion 600 μg·L-1 and oral at a dose of 40 mg·kg-1 feeds, E: immersion 600 μg·L-1 and oral at a dose of 50 mg·kg-1 feeds. Results showed that the use of bull testicle extract mixed to media at concentration of 3 ml L-1 produced red male nile of 69.07 %. In addition, the immersion of the extract at 500 μg·L-1 resulted the male of 86.71 %. Sex reversal by dipping at 600 μg·L-1 17α-methyltestosterone combined with oral administration at 40 mg·kg-1 produced the highest male of Nile Tilapia Java carp (86.67 %) compared with dipping, which produced 65.56 % of male. These results suggested that combination of dipping and oral is more effective for sex reversal.

FEEDING FREQUENCY OF NILE TILAPIA FED RATIONS SUPPLEMENTED WITH AMINO ACIDS

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EDUARDO ARRUDA TEIXEIRA LANNA

2016-01-01

Full Text Available The present study evaluated the feeding frequency of Nile tilapia (Oreochromis niloticus fed low-protein diets (29% crude protein supplemented with commercial amino acids (L-lysine-HCl, DL-methionine, and L-threonine. Sex-reversed Nile tilapia (240 of Thai origin, with initial body weight of 0.93 ± 0.03 g each, were allocated in a completely randomized design, to five groups with various feeding frequencies (2, 3, 4, 5, and 6 times a day. Six replications were conducted on separate experimental units comprising eight fishes each. The fish were maintained in 30 130-L aquariums, each equipped with individual water supply and controlled temperature and aeration. Fish were fed identical quantities among all treatments over a period of 30 days. Performance parameters, feed conversion efficiency, body composition, daily protein and fat deposition rates, and nitrogen retention efficiency were evaluated. Increased feeding frequency affected neither performance parameters nor body composition. Values for protein and fat deposition rates and nitrogen retention efficiency were significantly lower in fish fed twice daily than in those fed five times daily. Fish subjected to other feeding frequencies yielded intermediate values without any significant differences. The minimum feeding frequency of Nile tilapia fingerlings fed a low-protein ration supplemented with commercial amino acids is three times a day, owing to increased protein deposition rates and nitrogen retention efficiency.

The use of crude extracts from traditional medicinal plants to eliminate Trichodina sp. in tilapia (Oreochromis niloticus fingerlings

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Chanagun Chitmanat

2005-02-01

Full Text Available The treatment for ectoparasitic diseases in freshwater fish with formalin seems at present to be ineffective. For this reason it is evidently a useless cost. In addition, formalin possibly leaves toxic residues in fish flesh and in the environment which are eventually harmful to consumers. The alternative way to solve this problem is to use traditional medicinal plants instead. The purpose of this research is to determine the possibility of using garlic (Allium sativum and Indian almond (Terminalia catappa as optional chemicals to treat fish ectoparasites, Trichodina sp. The results showed that crude extracts of either garlic or Indian almond at 800 mg/l significantly (P < 0.05 eliminated Trichodina sp. infections in tilapia (average weight 3.62±0.06 g each. To evaluate the acute toxicity of these products to the host fish, groups of 20 tilapia (same size as abovewere exposed to 3 concentrations of each product for 96 h. Mortality was then determined. The 2 h LC50 for tilapia exposed to crude extract of garlic was 2,259.44 mg/L while the 16 h LC50 for tilapia exposed to Indian almond extract was 46,665.94 mg/L. This information is the beneficial and fundamental knowledge to develop guidelines to reduce the use of chemicals and antibiotics in freshwater fish culture businesses. The research is underway to determine the long-term effect of Indian almond and garlic to tilapia, if any.

Suitability of Using Duckweed as Feed and Treated Sewage as Water Source in Tilapia Aquaculture

International Nuclear Information System (INIS)

EI-Shafail, S.A.; Nasrl, F.A.; EI-Gohary, F.A. A.; Cijzen, H.J.; Steen, N.P.

2004-01-01

Use of treated effluent and duckweed biomass from a pilot-scale UASB-duckweed ponds system treating domestic sewage was evaluated in rearing Nile tilapia (Oreochromis niloticus). Nutritional value of duckweed as sole feed was compared with wheat bran. Two sources of water were used for each feed trial, treated-sewage and freshwater. The experiment was conducted in parallel with a conventional settled sewage-fed fishpond. Results of growth performance demonstrated that, in case of freshwater ponds specific growth rate (SGR) of tilapia fed on fresh duckweed was significantly (p 0.05) was observed between the two feeding regimes in treated sewage fed ponds. The SGR of tilapia reared in the treated sewage-wheat bran-fed pond (TWP) was significant higher (p <0.01) than the SGR in the freshwater-wheat bran-fed pond (FWP). On the other hand, due to the early spawning in the treated sewage-duckweed fed pond (TOP) SGR of tilapia in the latter was significantly lower (p <0.05) than the SGR in the freshwater-duckweed-fed pond (FDP). The results of net fish yield were 11.8, 8.9, 9.6 and 6.4 ton/ha/y in TDP, TWP, FDP and FWP, respectively. negative net yield (-0.16 ton/ha/y) was observed in the settled sewage- fed pond (SSP) due to high mortality

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

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Daniela Miotto BERNARDI

2016-01-01

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

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).

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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.

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.

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.

Treatments of tilapia (Oreochromis niloticus) using nitric oxide for quality improvement: Establishing a potential method for large-scale processing of farmed fish.

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Wang, Zi-Chao; Yan, Yuzhen; Su, Ping; Zhao, Mou-Ming; Xia, Ning; Chen, De-Wei

2018-07-01

To find a succedaneum of present methods for slaughtering tilapia, we have demonstrated the influence of nitric oxide (NO) (saturated NO solution) through euthanasia before slaughter on the animal welfare and muscle color of tilapia. The results suggested that NO euthanasia significantly improved the animal welfare and muscle color. Besides, the investigation of NO postmortem treatment on the muscle color and color stability of tilapia fillets suggested that NO postmortem treatment not only improved the muscle color and color stability but also prolonged the shelf-life of tilapia fillets during the refrigerated storage. To further investigate the effect of NO euthanasia on the quality of tilapia fillets and to estimate the safety of NO treatments (NO euthanasia and NO postmortem treatment) for the application of NO treatments in industrial manufacturing of tilapia and possibly of other fish species. NO euthanasia was adopted in this study following a simulated fish processing line. HbNO and MbNO values were measured to clarify the mechanism and process of NO euthanasia. The blood parameters, muscle pH, rigor index, drip loss and total volatile basic nitrogen (TVB-N) values were measured to evaluate the quality of the fillets obtained from NO euthanized tilapia. Besides, the nitrate (NO 3 - ) levels in the muscles after the refrigerated storage were detected to estimate the food safety of both NO euthanasia and NO postmortem treatment. Fillets obtained from the tilapia euthanized by NO showed a later reduction of muscle pH, a later onset of rigor mortis postmortem and less drip loss during the refrigerated storage than control. NO euthanasia caused less TVB-N than control and prolonged the shelf life of tilapia fillets. Moreover, the NO 3 - levels in the muscles of both NO euthanasia and NO postmortem treatment after the refrigerated storage were below the maximum permitted limit. Both the NO euthanasia and NO postmortem treatment are suitable for improving the

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.

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

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Kalujnaia, Svetlana; Hazon, Neil; Cramb, Gordon

2016-08-01

A single MIPS gene (Isyna1/Ino1) exists in eel and tilapia genomes with a single myo-d-inositol 3-phosphate synthase (MIPS) transcript identified in all eel tissues, although two MIPS spliced variants [termed MIPS(s) and MIPS(l)] are found in all tilapia tissues. The larger tilapia transcript [MIPS(l)] results from the inclusion of the 87-nucleotide intron between exons 5 and 6 in the genomic sequence. In most tilapia tissues, the MIPS(s) transcript exhibits much higher abundance (generally >10-fold) with the exception of white skeletal muscle and oocytes, in which the MIPS(l) transcript predominates. SW acclimation resulted in large (6- to 32-fold) increases in mRNA expression for both MIPS(s) and MIPS(l) in all tilapia tissues tested, whereas in the eel, changes in expression were limited to a more modest 2.5-fold increase and only in the kidney. Western blots identified a number of species- and tissue-specific immunoreactive MIPS proteins ranging from 40 to 67 kDa molecular weight. SW acclimation failed to affect the abundance of any immunoreactive protein in any tissue tested from the eel. However, a major 67-kDa immunoreactive protein (presumed to be MIPS) found in tilapia tissues exhibited 11- and 54-fold increases in expression in gill and fin samples from SW-acclimated fish. Immunohistochemical investigations revealed specific immunoreactivity in the gill, fin, skin, and intestine taken from only SW-acclimated tilapia. Immunofluorescence indicated that MIPS was expressed within gill chondrocytes and epithelial cells of the primary filaments, basal epithelial cell layers of the skin and fin, the cytosol of columnar intestinal epithelial and mucous cells, as well as unknown entero-endocrine-like cells. Copyright © 2016 the American Physiological Society.

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

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Gonzales, John M.; Brown, Paul B.

2006-01-01

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

Phosphoglycerate kinase enhanced immunity of the whole cell of Streptococcus agalactiae in tilapia, Oreochromis niloticus.

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Wang, Yi-Ting; Huang, Hsing-Yen; Tsai, Ming-An; Wang, Pei-Chi; Jiang, Bo-Huang; Chen, Shih-Chu

2014-12-01

Streptococcus agalactiae is a Gram-positive bacterium and a severe aquaculture pathogen that can infect a wide range of warmwater fish species. The outer-surface proteins in bacterial pathogens play an important role in pathogenesis. We evaluated the immunogenicity of two of the identified surface proteins namely phosphoglycerate kinase (PGK) and ornithine carbamoyl-transferase (OCT). PGK and OCT were over-expressed and purified from Escherichia coli and used as the subunit vaccines in tilapia. Tilapia immunized with the S. agalactiae modified bacteria vaccine (whole cell preparations with recombinant PGK and OCT proteins) individually were tested for the efficacy. OCT and PGK combined with WC had a higher survival rate. A high-level protection and significant specific antibody responses against S. agalactiae challenge was observed upon the vaccinated tilapia with the purified PGK protein and S. agalactiae whole cells. The specific antibody titer against S. agalactiae antigen suggested that increased antibody titers were correlated with post-challenge survival rate. Il-1β expression profile was higher in PGK + WC-treated group. Tnf-α expression in the PGK + WC group was significantly increased. Taken together, our results suggested the combinations of recombinant protein and whole cell may elicit immune responses that reach greater protection than that of individual S. agalactiae components. Copyright © 2014 Elsevier Ltd. All rights reserved.

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

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F. A Sebastião

2011-03-01

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

Live transport of Yellow Perch and Nile Tilapia in AQUI-S 20E (10% Eugenol) at high loading densities

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Cupp, Aaron R.; Schreier, Theresa M.; Schleis, Sue M.

2017-01-01

Fish transport costs are a substantial portion of the operational expenses for aquaculture facilities in the USA. Safely transporting higher loading densities of fish would benefit haulers by increasing efficiency and reducing costs, but research evaluating transport for individual species is generally lacking. In this study, Yellow Perch Perca flavescens and Nile Tilapia Oreochromis niloticus were transported for 6 h immersed in water containing AQUI-S 20E (10% eugenol) at fish loading densities of 240 g/L (2 lb/gal) for perch and 480 g/L (4 lb/gal) for tilapia. Survival was quantified for fish transported in AQUI-S 20E concentrations of (1) control or 0 mg/L of water, (2) 100 mg/L, or (3) 200 mg/L. Yellow Perch had 98–100% survival, and Nile Tilapia had 100% survival up to through 14 d after transport across all AQUI-S 20E levels, including the control. Eugenol concentrations decreased rapidly in transport tank water, and fish showed no signs of sedation by the end of transport. We conclude that live transport of Yellow Perch and Nile Tilapia at higher loading densities resulted in high survival regardless of the AQUI-S 20E concentrations we tested.

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).

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

Science.gov (United States)

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

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...

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)

Genetic parameters for fillet traits and body measurements in Nile tilapia (Oreochromis niloticus L.)

NARCIS (Netherlands)

Rutten, M.J.M.; Bovenhuis, H.; Komen, J.

2005-01-01

Fillet weight is an economically important trait in Nile tilapia production for the European market which asks for fish with average body weights of at least 700 g. Genetic parameters to design or optimize breeding programs for these body weights are lacking. In an earlier study we showed that high

Suitability of Using Duckweed as Feed and Treated Sewage as Water Source in Tilapia Aquaculture

Energy Technology Data Exchange (ETDEWEB)

EI-Shafail, S A; Nasrl, F A; EI-Gohary, F.A. A. [Water Pollution Control Department, National Research Centre, Dokki, Giza (Egypt); Cijzen, H J; Steen, N P [Environmental Resources Department, UNESCO-IHE Institute, Delft (Netherlands)

2004-07-01

Use of treated effluent and duckweed biomass from a pilot-scale UASB-duckweed ponds system treating domestic sewage was evaluated in rearing Nile tilapia (Oreochromis niloticus). Nutritional value of duckweed as sole feed was compared with wheat bran. Two sources of water were used for each feed trial, treated-sewage and freshwater. The experiment was conducted in parallel with a conventional settled sewage-fed fishpond. Results of growth performance demonstrated that, in case of freshwater ponds specific growth rate (SGR) of tilapia fed on fresh duckweed was significantly (p < 0.01) higher than the SGR in wheat bran fed pond. No significant difference (p > 0.05) was observed between the two feeding regimes in treated sewage fed ponds. The SGR of tilapia reared in the treated sewage-wheat bran-fed pond (TWP) was significant higher (p <0.01) than the SGR in the freshwater-wheat bran-fed pond (FWP). On the other hand, due to the early spawning in the treated sewage-duckweed fed pond (TOP) SGR of tilapia in the latter was significantly lower (p <0.05) than the SGR in the freshwater-duckweed-fed pond (FDP). The results of net fish yield were 11.8, 8.9, 9.6 and 6.4 ton/ha/y in TDP, TWP, FDP and FWP, respectively. negative net yield (-0.16 ton/ha/y) was observed in the settled sewage- fed pond (SSP) due to high mortality.

Random regression analysis for body weights and main morphological traits in genetically improved farmed tilapia (Oreochromis niloticus).

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He, Jie; Zhao, Yunfeng; Zhao, Jingli; Gao, Jin; Xu, Pao; Yang, Runqing

2018-02-01

To genetically analyse growth traits in genetically improved farmed tilapia (GIFT), the body weight (BWE) and main morphological traits, including body length (BL), body depth (BD), body width (BWI), head length (HL) and length of the caudal peduncle (CPL), were measured six times in growth duration on 1451 fish from 45 mixed families of full and half sibs. A random regression model (RRM) was used to model genetic changes of the growth traits with days of age and estimate the heritability for any growth point and genetic correlations between pairwise growth points. Using the covariance function based on optimal RRMs, the heritabilities were estimated to be from 0.102 to 0.662 for BWE, 0.157 to 0.591 for BL, 0.047 to 0.621 for BD, 0.018 to 0.577 for BWI, 0.075 to 0.597 for HL and 0.032 to 0.610 for CPL between 60 and 140 days of age. All genetic correlations exceeded 0.5 between pairwise growth points. Moreover, the traits at initial days of age showed less correlation with those at later days of age. With phenotypes observed repeatedly, the model choice showed that the optimal RRMs could more precisely predict breeding values at a specific growth time than repeatability models or multiple trait animal models, which enhanced the efficiency of selection for the BWE and main morphological traits.

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

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Rodrigo Diana Navarro

2015-10-01

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

The motility and motion duration of jatimbulan tilapia (Oreochromis niloticus) spermatozoa in different salinity

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Triastuti, J.; Kintani, D.; Luqman, E. M.; Pujiastuti, D. Y.

2018-04-01

Tilapia hatchery is still conducted in freshwater and seeds are death simultaneousy when cultivated in high salinity due to the acclimatization process. An alternative method to implement hatchery at high salinity is required. This study aims to determine the salinity of activation medium that provides the best Jatimbulan Tilapia sperm motility and motion duration at high salinity. The study applies completely randomized design (CRD), which consists of 5 treatments (0 ppt, 4 ppt, 9 ppt, 14 ppt and 19 ppt) and 4 repetitions. The parameters consists of sperm motility, motion duration, fresh sperm data (volume, color, odor, pH, consistency, and the concentration of sperm) and sperm abnormalities. The results exhibited that salinity significantly (p < 0.05). Influeneed the sperm motility and motion duration. Motility reaches its best at 0 ppt and 4 ppt (93.4 % and 87.8 %). For motion duration, best condition was in 0 ppt and 4 ppt treatments, totaling 2128 seconds and 1961.5 seconds. Meanwhile, sperm did not move when treated in waters with 9 ppt, 14 ppt and 19 ppt salinities.

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.

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

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

Effect of different periods of pre-slaughter stress on the quality of the Nile tilapia meat

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Pedro Luiz de CASTRO

2016-01-01

Full Text Available Abstract The study was carried out with the objective of evaluating the influence of pre-slaughter stress on meat quality of Nile tilapia (O. niloticus for 10 days of storage in ice. 75 whole fish were used eviscerated, with average weight and length of 825.75 ± 101.59 g and 28.25 ± 0.81 cm, respectively. The treatments consisted of time in which the animals underwent pre-slaughter hypoxia, being 0, 3 and 6 minutes. Rigor mortis and muscle pH were assessed besides the application of the Quality Index Method and analysis of total protein and blood glucose. Rigor mortis did not differ among treatments during the storage period, and after three hours all animals were in rigor stage. The muscle pH values varied widely during the study period, observing higher values on the third day of storage. Sensory analysis showed that after 10 days the tilapia from the different treatments did not differ in the evaluated quality parameters similarly, there was no difference regarding the evaluated blood biochemical parameters Thus, hypoxia of 6 minutes pre-slaughter does not influence the rigor mortis, muscle pH, qualitative perception of the meat quality, total protein and blood glucose of Nile tilapia.

Effect of different periods of pre-slaughter stress on the quality of the Nile tilapia meat

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Pedro Luiz de CASTRO

Full Text Available Abstract The study was carried out with the objective of evaluating the influence of pre-slaughter stress on meat quality of Nile tilapia (O. niloticus for 10 days of storage in ice. 75 whole fish were used eviscerated, with average weight and length of 825.75 ± 101.59 g and 28.25 ± 0.81 cm, respectively. The treatments consisted of time in which the animals underwent pre-slaughter hypoxia, being 0, 3 and 6 minutes. Rigor mortis and muscle pH were assessed besides the application of the Quality Index Method and analysis of total protein and blood glucose. Rigor mortis did not differ among treatments during the storage period, and after three hours all animals were in rigor stage. The muscle pH values varied widely during the study period, observing higher values on the third day of storage. Sensory analysis showed that after 10 days the tilapia from the different treatments did not differ in the evaluated quality parameters similarly, there was no difference regarding the evaluated blood biochemical parameters Thus, hypoxia of 6 minutes pre-slaughter does not influence the rigor mortis, muscle pH, qualitative perception of the meat quality, total protein and blood glucose of Nile tilapia.

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

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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

Efficiency of aquatic macrophytes to treat Nile tilapia pond effluents

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Henry-Silva Gustavo Gonzaga

2006-01-01

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

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.

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

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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.

CARACTERIZACIÓN DE COPRODUCTOS DE LA INDUSTRIA DEL FILETEADO DE TILAPIA NILÓTICA (Oreochromis niloticus Y TRUCHA ARCOÍRIS (Oncorhynchus mykiss EN COLOMBIA

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A. Osorio

2013-01-01

Full Text Available La industria del fileteado de tilapia y trucha genera cantidades significativas de coproductos de los cuales no existe suficiente información disponible sobre su composición y calidad. Esta investigación determinó algunos componentes nutricionales y microbiológicos de coproductos obtenidos en plantas exportadoras de filetes de tilapia nilótica y trucha arcoíris en Colombia. El esqueleto mostró el mayor aporte de cenizas (tilapia: 14,12 ± 0,16%; trucha: 6,18 ± 0,06%, calcio (tilapia: 5,70 ± 0,04%; trucha: 1,72 ± 0,08% y fósforo (tilapia: 1,89 ± 0,06%; trucha: 0,84 ± 0,03%, mientras que los recortes presentaron la mayor concentración de extracto etéreo (tilapia: 30,10 ± 0,58%; trucha: 17,50 ± 0,51% y la carne mecánicamente separada, los mayores contenidos de humedad (tilapia: 70,38 ± 0,18%; trucha: 72,93 ± 0,3% y proteína (tilapia: 14,32 ± 0,03%; trucha: 18,88 ± 0,05%. El mayor aporte de ácidos grasos polinsaturados (AGPI, como porcentaje del total de ácidos grasos identificados, se encontró en esqueleto de tilapia (17,27% y en recortes de trucha (38,68%, con relaciones n6/n3 de 2,67 y 0,71, respectivamente. En general, los coproductos estudiados cumplieron con los estándares microbiológicos exigidos por la normatividad colombiana (Resolución 122 de 2012 del Ministerio de Salud y Protección Social que establece los requisitos fisicoquímicos y microbiológicos que deben cumplir los productos de la pesca, en particular pescados, moluscos y crustáceos para consumo humano. Los resultados muestran que los coproductos estudiados contienen un importante aporte de proteína, cenizas, ácidos grasos poli-insaturados y adecuada calidad microbiológica, con potencial para alimentación humana o animal.

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

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Flavio Endrigo Cechim

2012-12-01

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

Dietary microbial phytase exerts mixed effects on the gut health of tilapia: a possible reason for the null effect on growth promotion.

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Hu, Jun; Ran, Chao; He, Suxu; Cao, Yanan; Yao, Bin; Ye, Yuantu; Zhang, Xuezhen; Zhou, Zhigang

2016-06-01

The present study evaluated the effects of dietary microbial phytase on the growth and gut health of hybrid tilapia (Oreochromis niloticus ♀×Oreochromis aureus ♂), focusing on the effect on intestinal histology, adhesive microbiota and expression of immune-related cytokine genes. Tilapia were fed either control diet or diet supplemented with microbial phytase (1000 U/kg). Each diet was randomly assigned to four groups of fish reared in cages (3×3×2 m). After 12 weeks of feeding, weight gain and feed conversion ratio of tilapia were not significantly improved by dietary microbial phytase supplementation. However, significantly higher level of P content in the scales, tighter and more regular intestinal mucosa folds were observed in the microbial phytase group and the microvilli density was significantly increased. The adhesive gut bacterial communities were strikingly altered by microbial phytase supplementation (0·41phytase, as indicated by the up-regulated intestinal expressions of the cytokine genes (tnf-α and tgf-β) and hsp70. In addition, the gut microvilli height was significantly decreased in the phytase group. These results indicate that dietary microbial phytase may exert mixed effects on hybrid tilapia, and can guide our future selection of phytases as aquafeed additives - that is, eliminating those that can stimulate intestinal inflammation.

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

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

2015-07-01

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

Species-specific content of As, Pb, and other elements in pangas (Pangasianodon hypophthalmus) and tilapia (Oreochromis niloticus) from aquaculture ponds in southern Bangladesh

DEFF Research Database (Denmark)

Marcussen, Helle; Alam, Md. Ariful; Rahman, Md. Mizanur

2014-01-01

Content of arsenic and lead and 10 other potentially toxic elements (Ba, Ce, Cr, Cu, Fe,Mg,Mn, Se, Sr and Zn) was determined in tilapia and pangas from aquaculture ponds in southern Bangladesh. Tilapia had 1.6- to 4.3-fold higher content of Mn, As, Sr, and Ba than pangas, possibly caused...... by different feeding habits of the two fish. The other elements had similar concentrations in both species. Content of As in tilapia and pangas was 0.37 and 0.11 μg g−1, respectively, while Pb made up 0.056 and 0.051 μg g−1, respectively. Water treatment during the farming period (sand filtration and probiotic...... bacteria) and final depuration in groundwater for up to 48 h had no effect on content of the elements. For As, consumption of 100 g fresh fish per day contained 1.3% (pangas) and 5% (tilapia) of the maximum tolerable daily intake according to FAO recommendations. Relative to whole tilapia froma lake near...

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

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

Dietary camu camu, Myrciaria dubia, enhances immunological response in Nile tilapia.

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Yunis-Aguinaga, Jefferson; Fernandes, Dayanne C; Eto, Silas F; Claudiano, Gustavo S; Marcusso, Paulo F; Marinho-Neto, Fausto A; Fernandes, João B K; de Moraes, Flávio R; de Moraes, Julieta R Engrácia

2016-11-01

Camu camu, Myrciaria dubia, is an Amazon plant that presents high levels of vitamin C in its composition. Several studies in animals and humans have demonstrated their efficiency in the prevention and treatment of various diseases. However, there are no reports of its properties in fish. The aim of this study was to evaluate the effect of the oral administration of the extract of this plant in the immune parameters in Nile tilapia, Oreochromis niloticus. 400 Nile tilapia (80 ± 5 g) were randomly distributed into 20 tanks with 1500 L capacity each (20 fish/tank). After a week of adaptation to environmental conditions, it was provided a diet for 5 weeks, using different levels of inclusion of camu camu extract: 0, 50, 100, 250, and 500 mg/kg of feed. Each treatment consisted of four replicates. It was obtained 40.5 mg of vitamin C/g of camu camu pulp powder by high-performance liquid chromatography. At the end of the trial period, fish were inoculated with Aeromonas hydrophila in the swim bladder. Samples were taken after 6; 24 and 48 h of the challenge. Results revealed that fish supplemented with this herb showed significant increase (P  0.05). No histopathological lesions were observed in intestine, kidney, spleen, and gills. It can be concluded that the addition of Myrciaria dubia in tilapia feed improves the immune response and the growth after 5 weeks, especially, at a dose of 500 mg/kg. Copyright © 2016. Published by Elsevier Ltd.

Competitive Interactions between Invasive Nile Tilapia and Native Fish: The Potential for Altered Trophic Exchange and Modification of Food Webs

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Martin, Charles W.; Valentine, Marla M.; Valentine, John F.

2010-01-01

Recent studies have highlighted both the positive and negative impacts of species invasions. Most of these studies have been conducted on either immobile invasive plants or sessile fauna found at the base of food webs. Fewer studies have examined the impacts of vagile invasive consumers on native competitors. This is an issue of some importance given the controlling influence that consumers have on lower order plants and animals. Here, we present results of laboratory experiments designed to assess the impacts of unintended aquaculture releases of the Nile tilapia (Oreochromis niloticus), in estuaries of the Gulf of Mexico, on the functionally similar redspotted sunfish (Lepomis miniatus). Laboratory choice tests showed that tilapia prefer the same structured habitat that native sunfish prefer. In subsequent interspecific competition experiments, agonistic tilapia displaced sunfish from their preferred structured habitats. When a piscivore (largemouth bass) was present in the tank with both species, the survival of sunfish decreased. Based on these findings, if left unchecked, we predict that the proliferation of tilapia (and perhaps other aggressive aquaculture fishes) will have important detrimental effects on the structure of native food webs in shallow, structured coastal habitats. While it is likely that the impacts of higher trophic level invasive competitors will vary among species, these results show that consequences of unintended releases of invasive higher order consumers can be important. PMID:21200433

Competitive interactions between invasive Nile tilapia and native fish: the potential for altered trophic exchange and modification of food webs.

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Charles W Martin

2010-12-01

Full Text Available Recent studies have highlighted both the positive and negative impacts of species invasions. Most of these studies have been conducted on either immobile invasive plants or sessile fauna found at the base of food webs. Fewer studies have examined the impacts of vagile invasive consumers on native competitors. This is an issue of some importance given the controlling influence that consumers have on lower order plants and animals. Here, we present results of laboratory experiments designed to assess the impacts of unintended aquaculture releases of the Nile tilapia (Oreochromis niloticus, in estuaries of the Gulf of Mexico, on the functionally similar redspotted sunfish (Lepomis miniatus. Laboratory choice tests showed that tilapia prefer the same structured habitat that native sunfish prefer. In subsequent interspecific competition experiments, agonistic tilapia displaced sunfish from their preferred structured habitats. When a piscivore (largemouth bass was present in the tank with both species, the survival of sunfish decreased. Based on these findings, if left unchecked, we predict that the proliferation of tilapia (and perhaps other aggressive aquaculture fishes will have important detrimental effects on the structure of native food webs in shallow, structured coastal habitats. While it is likely that the impacts of higher trophic level invasive competitors will vary among species, these results show that consequences of unintended releases of invasive higher order consumers can be important.

Incorporation and fatty acid composition in liver of Nile tilapia fed with flaxseed oil - doi: 10.4025/actascitechnol.v33i2.7970

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Polyana Batoqui França

2011-04-01

Full Text Available One of the most consumed freshwater fish in South America is Nile tilapia. The present study examined the effects of flaxseed oil (FO, source of alfa-linolenic acid (LNA, on the total lipid composition and polyunsaturated fatty acid, n-6 and n-3 PUFA, contents on Nile tilapia (Oreochromis niloticus liver. Tilapias were given diets with increasing levels 0.00, 1.2, 2.50, 3.75 and 5.00% (w w-1 of FO as a replacement of sunflower oil for five months. Fatty acids analysis of methyl esters revealed 45 fatty acids common to all treatments. The increase of flaxseed oil resulted in a decrease in total n-6 PUFA (35.1 to 21.1% and an increase in n-3 PUFA (3.3 to 18.5%. The diet with LNA underwent sequential desaturation and elongation in liver, leading to an increase in all n-3 PUFA and a decrease in n-6/n-3 ratios (10.7 to 1.1. The manipulation of fatty acids with FO may be used to increase n-3 PUFA and to help balance n-6/n-3 PUFA in dietary supplements, thus, the liver tilapia becomes one product with major nutritional value.

Inhibition of miR-92d-3p enhances inflammation responses in genetically improved farmed tilapia (GIFT, Oreochromis niloticus) with Streptococcus iniae infection by modulating complement C3.

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

2017-04-01

MicroRNAs (miRNAs) are small, non-coding RNAs that regulate target gene expression by binding to the 3'-untranslated regions (3'-UTRs) of their target mRNAs. The miR-92 family is an important miRNA family, which was discovered to be related to regulation of tumor proliferation, apoptosis, invasion, and metastasis. Inhibition of miR-92d-3p was found previously in head kidney of genetically improved farmed tilapia (GIFT, Oreochromis niloticus) exposed to Streptococcus iniae infection. In this study, we found that miR-92d-3p regulated complement C3 mRNA levels by binding to its 3'-UTR by 3'-UTR luciferase reporter assay, and reduced miR-92d-3p expression resulted in increased C3 mRNA levels. We detected a negative relationship between the expression levels of miR-92d-3p and C3 in GIFT injected with miRNA antagomir. We performed in vivo functional analysis by miR-92d-3p silencing. Inhibition of miR-92d-3p levels in GIFT head kidney caused a significant increase in C3 expression, which consequently increased the white blood cell counts and interleukin-1β, tumor necrosis factor-α, and interferon-γ mRNA levels, all of which may help to activate the inflammatory response in GIFT post-infection with S. iniae. Our findings indicate that miR-92d-3p regulated C3 levels by binding with the C3 mRNA 3'-UTR, and this interaction affected S. iniae infection induction and the immune response in GIFT. We concluded that miR-92d-3p plays an important role in modulating the inflammatory response in GIFT head kidney. Our findings may contribute to understanding the mechanisms of miRNA-mediated gene regulation in tilapia in response to S. iniae infection. Copyright © 2017 Elsevier Ltd. All rights reserved.

Natural coinfection by Streptococcus agalactiae and Francisella noatunensis subsp. orientalis in farmed Nile tilapia (Oreochromis niloticus L.).

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Assis, G B N; Tavares, G C; Pereira, F L; Figueiredo, H C P; Leal, C A G

2017-01-01

Streptococcus agalactiae and Francisella noatunensis subsp. orientalis (Fno) are important pathogens for farm-raised tilapia worldwide. There are no reports of coinfection caused by S. agalactiae and Fno in fish. This study aimed to determine the aetiology of atypical mortalities in a cage farm of Nile tilapia and to characterize the genetic diversity of the isolates. Fifty-two fish were sampled and subjected to parasitological and bacteriological examination. The S. agalactiae and Fno isolates were genotyped using MLST and REP-PCR, respectively. Whole-genome sequencing was performed to confirm the MLST results. Seven fish were shown coinfected by S. agalactiae and Fno. Chronic hypoxia and a reduction in the water temperature were determined as risk factors for coinfection. Fno isolates were shown clonally related in REP-PCR. The MLST analysis revealed that the S. agalactiae isolates from seven coinfected fish were negative for the glcK gene; however, these were determined to be members of clonal complex CC-552. This is the first description of coinfection by S. agalactiae and Fno in farm-raised Nile tilapia. The coinfection was predisposed by chronic hypoxia and was caused by the main genotypes of S. agalactiae and Fno reported in Brazil. Finally, a new S. agalactiae genotype with glcK gene partially deleted was described. © 2016 John Wiley & Sons Ltd.

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

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

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

Unique nuclear localization of Nile tilapia (Oreochromis niloticus) Neu4 sialidase is regulated by nuclear transport receptor importin α/β.

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Honda, Akinobu; Chigwechokha, Petros Kingstone; Kamada-Futagami, Yuko; Komatsu, Masaharu; Shiozaki, Kazuhiro

2018-06-01

Sialidase catalyzes the removal of sialic acids from glycoconjugates. Different from Neu1 and Neu3 sialidases, Neu4 enzymatic properties such as substrate specificity and subcellular localization are not well-conserved among vertebrates. In fish only zebrafish and medaka neu4 genes have been cloned and their polypeptides have been characterized so far. Thus, characterization of Neu4 from other fish species is necessary to evaluate Neu4 physiological functions. Here, Nile tilapia was chosen for the characterization of Neu4 polypeptide considering that it is one of the major cultured fish all over the world and that its genomic sequences are now available. Coding DNA sequence of tilapia Neu4 was identified as 1,497 bp and its recombinant protein showed broad substrate specificity and optimal sialidase enzyme activity pH at 4.0. Neu4 activity was sustained even in neutral and alkali pH. Interestingly, immunofluorescence analysis revealed that major subcellular localization of tilapia Neu4 was nuclear, quite distinct from zebrafish (ER) and medaka Neu4 (lysosome). Bioinformatic analysis showed the existence of putative nuclear localization signal (NLS) in tilapia Neu4. In general, it is known that importin families bind to several proteins via NLS and transfer them into nucleus. Therefore, to determine the involvement of putative NLS in Neu4 nuclear localization, Neu4 mutant deleting NLS was constructed and expressed in cultured cells. As a result, NLS deletion significantly diminished the nuclear localization. Furthermore, treatment of importazole, interrupter of binding importin β and RanGTP, significantly suppressed Neu4 nuclear localization. In summary, tilapia Neu4 is a unique sialidase localized at nucleus and its transport system into nucleus is regulated by importin. Copyright © 2018 Elsevier B.V. and Société Française de Biochimie et Biologie Moléculaire (SFBBM). All rights reserved.

A comparative study of the metabolic response in rainbow trout and Nile tilapia to changes in dietary macronutrient composition.

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

2013-03-14

Metabolic mechanisms underlying the divergent response of rainbow trout (Oncorhynchus mykiss) and Nile tilapia (Oreochromis niloticus) to changes in dietary macronutrient composition were assessed. Fish were fed one of four isoenergetic diets having a digestible protein-to-digestible energy (DP:DE) ratio above or below the optimal DP:DE ratio for both species. At each DP:DE ratio, fat was substituted by an isoenergetic amount of digestible starch as the non-protein energy source (NPE). Dietary DP:DE ratio did not affect growth and only slightly lowered protein gains in tilapia. In rainbow trout fed diets with low DP:DE ratios, particularly with starch as the major NPE source, growth and protein utilisation were highly reduced, underlining the importance of NPE source in this species. We also observed species-specific responses of enzymes involved in amino acid catabolism, lipogenesis and gluconeogenesis to dietary factors. Amino acid transdeamination enzyme activities were reduced by a low dietary DP:DE ratio in both species and in tilapia also by the substitution of fat by starch as the NPE source. Such decreased amino acid catabolism at high starch intakes, however, did not lead to improved protein retention. Our data further suggest that a combination of increased lipogenic and decreased gluconeogenic enzyme activities accounts for the better use of carbohydrates and to the improved glycaemia control in tilapia compared with rainbow tront fed starch-enriched diets with low DP:DE ratio.

Impact of microcystin containing diets on physiological performance of Nile tilapia (Oreochromis niloticus) concerning stress and growth

Czech Academy of Sciences Publication Activity Database

Ziková, A.; Trubiroha, A.; Wiegand, C.; Wuertz, S.; Rennert, B.; Pflugmacher, S.; Kopp, Radovan; Mareš, J.; Kloas, W.

2010-01-01

Roč. 29, č. 3 (2010), s. 561-568 ISSN 0730-7268 Institutional research plan: CEZ:AV0Z60050516 Keywords : microcystin * Nile tilapia * physiological performance Subject RIV: EF - Botanics Impact factor: 3.026, year: 2010

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

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Nilton Garcia-Marengoni

2015-05-01

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

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

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.

El cultivo de tilapias: una amenaza a las especies ícticas nativas en Nicaragua.

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McCrary, J.K.

2001-08-01

Full Text Available El cultivo de tilapia del nilo (oreochromis niloticus, linnoeus previamente alimentados con hormonas para producir machos, en la laguna de Apoyo en Nicaragua ha permitido la introducción a la laguna de individuos, incluyendo hembras fecundas. Discutimos las consecuencias de esta introducción, en términos de amenazas de extinción de especies endémicas nativas a través de destrucción de hábitat, competencia por sitios de cortejo y alimentación, proliferación de parásitos en poblaciones de fauna nativa, y la depredación de alevines nativos. Mientras que una liberación anterior de una especie similar (O. aureus Steindachner en la laguna de Apoyo, en 1983, tuvo poco impacto observado, este segundo incidente, aquí documentado, ha resultado en dramáticos impactos negativos en la laguna, amenazando especies endémicas locales y creando posiblemente riesgos en la salud humana. Abogamos por la remoción total de tilapias de ecosistemas naturales como el de Apoyo, y advertimos sobre el peligro de las introducciones de especies no nativas en ecosistemas naturales, aun donde introducciones previas han sucedido.

a survey of the artisanal fisheries of kontagora reservoir, niger state

African Journals Online (AJOL)

DR. AMINU

, Nigeria. Fish families /Species. English. Local Name. Cichlidae. Tilapia melanopleura. Tilapia. Gargaza. Hemichromis fasciatus. Tiliapia. Kulkula. Cyprinidae. Barilius niloticus. Barb. Dankursa. Bagridae. Auchenoglanis occidentalis. Cat fish.

Identification of ace inhibitory cryptides in Tilapia protein hydrolysate by UPLC-MS/MS coupled to database analysis.

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Yesmine, Ben Henda; Antoine, Bonnet; da Silva Ortência Leocádia, Nunes Gonzalez; Rogério, Boscolo Wilson; Ingrid, Arnaudin; Nicolas, Bridiau; Thierry, Maugard; Jean-Marie, Piot; Frédéric, Sannier; Stéphanie, Bordenave-Juchereau

2017-05-01

An ultra-performance liquid chromatography-quadrupole-time of flight mass spectrometry method was developed and applied to identify short angiotensin-I-converting enzyme (ACE) inhibitory cryptides in Tilapia (Oreochromis Niloticus) protein hydrolyzate. A database was created with previously identified ACE-inhibitory di- and tripeptides and the lowest molecular weight fraction of Tilapia hydrolysate was analysed for coincidences. Only VW and VY were identified. Further analysis of collected fractions conducted to the identification of 51 different peptides in major fractions. 19 peptides selected were synthesised and tested for their ACE inhibitory potential. TL, TI, IK, LR, LD, IQ, DI, AILE, ALLE, ALIE and AIIE were identified as new ACE inhibitors. The findings from this study point UPLC-MS/MS combined with the creation of a database as an efficient technique to identify specific short peptides within a complex hydrolysate, in addition with de novo sequencing. This efficient characterisation of bioactive factors like cryptides in protein hydrolysates will extend their use as functional foods. Copyright © 2017 Elsevier B.V. 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

Caracterización de coproductos de la industria del fileteado de tilapia nilótica (oreochromis niloticus) y trucha arcoíris (oncorhynchus mykiss) en colombia

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Osorio, A.; Wills, A.; Muñoz, A. P.

2013-01-01

La industria del fileteado de tilapia y trucha genera cantidades significativas de coproductos de los cuales no existe suficiente información disponible sobre su composición y calidad. Esta investigación determinó algunos componentes nutricionales y microbiológicos de coproductos obtenidos en plantas exportadoras de filetes de tilapia nilótica y trucha arcoíris en Colombia. El esqueleto mostró el mayor aporte de cenizas (tilapia: 14,12 ± 0,16%; trucha: 6,18 ± 0,06%), calcio (tilapia: 5,7...

Changes in the physiological parameters, fatty acid metabolism, and SCD activity and expression in juvenile GIFT tilapia (Oreochromis niloticus) reared at three different temperatures.

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Ma, X Y; Qiang, J; He, J; Gabriel, N N; Xu, P

2015-08-01

We evaluated the effects of rearing temperature on the composition of fatty acids and stearoyl-CoA desaturase (SCD) activity and gene expression in GIFT (genetically improved farmed tilapia) tilapia. Three triplicate groups of fish were reared for 40 days at 22, 28, or 34 °C. At the end of the trial, the final body weight of juveniles reared at 28 °C was higher than that of fish reared at 22 or 34 °C. Feed intake, feed efficiency, and the protein efficiency ratio were also higher at 28 °C. The fatty acid composition of muscle tissue differed significantly (P GIFT tilapia muscle. Additionally, cold acclimation can decrease the content of TC and TG in GIFT tilapia, which can help increase cold tolerance.

Limnological characteristics of a reservoir in semiarid Northeastern Brazil subject to intensive tilapia farming (Orechromis niloticus Linnaeus, 1758

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Luis Artur Valões Bezerra

2014-03-01

Full Text Available AIM: There is currently no consensus regarding the physical and chemical variability of tropical reservoirs. In semiarid Northeastern Brazil, reservoirs are among other things used for human consumption, industrial water supply and intensive fish farming, all of which can impact water quality. The objective of this study was to evaluate the physical and chemical variability of the water in Sítios Novos, a reservoir in semiarid Northeastern Brazil, comparing samples collected in areas of intensive tilapia (Oreochromis niloticus farming to samples from areas not directly impacted by aquaculture, in both the dry and the rainy season. METHODS: Between October 2010 and July 2011, data were collected on temperature, conductivity, pH, turbidity, salinity, chlorophyll a, dissolved oxygen, oxygen demand, total phosphorus and total nitrogen levels in the water column using a multiparametric probe at four different sampling locations. Physical and chemical differences between the four locations were evaluated with the Kruskal-Wallis (KW test and Dunn's post test, while the t test, followed by Welchʼs correction, was used to compare samples collected in different seasons. RESULTS: No influence of intensive aquaculture was detected when comparing sampling locations near fish farms (180C and 300C to locations not directly impacted by aquaculture (LIMN1, near the dam, and LIMN2, near the debouch of the São Gonçalo river. However, the sampling locations differed significantly (p<0.05 with regard to conductivity, pH, turbidity and chlorophyll a levels. CONCLUSIONS: The physical and chemical variability was greater between seasons than between locations when the data were analyzed with the t test. That analysis showed significant differences for 22 of 40 comparisons between the 10 physical and chemical parameters in the two seasons at the four sampling locations. In conclusion, the physical and chemical variability registered for the Sítios Novos reservoir

Use of mathematical models in the study of bodily growth in GIFT strain Nile tilapia

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Alda Lúcia de Lima Amancio

Full Text Available The objective of this study was to evaluate the accuracy of five mathematical models (Gompertz, Logistic, Linear Hyperbolic, Quadratic and Quadratic Logarithmic to describe the growth curve of GIFT strain Nile tilapia, Oreochromis niloticus, and to characterize the growth trajectory of body parts. To do this, 1,000 fingerlings, with an initial weight of 2.4 g were placed into 20 brick tanks of 2 m³ each, at a density of 25 fish m-3, for 180 days. The animals were fed daily, using the protein levels and number of meals appropriate to each stage. Every two weeks 20 fish were randomly sampled, submitted to a fasting period of 48 h and then slaughtered by thermal shock, in order to determine the weight of the whole fish, the skin without scales, skinless fillets, heart, liver, gills and gastrointestinal tract. The Gompertz and Logistic models presented the best fit to the growth curve for live weight, fillet and skin, however the Logistic model underestimated the asymptotic weights. Therefore, to describe the growth curve in GIFT strain Nile tilapia, the Gompertz model is suggested. According to the parameters estimated by the Gompertz model, Nile tilapia reach the age for maximum growth of the fillet and skin before that of body weight. Among the organs studied, growth of the gastrointestinal tract and gills takes place earlier than that of the heart and liver.

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.

EVALUACIÓN DE UN SISTEMA DE ALIMENTACIÓN ORGÁNICO SOBRE EL DESEMPEÑO PRODUCTIVO DE LA TILAPIA NILÓTICA (Oreochromis niloticus CULTIVADA EN ESTANQUES DE TIERRA

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A. Bermúdez

2012-01-01

Full Text Available Se evaluó el efecto de un sistema de alimentación integrado por dietas formuladas con recursos alternativos orgánicos y diferentes niveles de fertilización orgánica sobre pará- metros zootécnicos en peces de consumo cultivados en estanques de tierra. Se utilizaron 1.324 juveniles de Tilapia nilótica (Oreochromis niloticus cuyo peso inicial promedio fue de 161,9 ± 7,0 g, solo machos sexados manualmente, sin reversión hormonal. Se empleó un diseño completamente al azar con tres tratamientos y tres repeticiones, distribuidos en 9 estanques de tierra (200 m2 cada uno, cultivados bajo las normas de Naturland (2007, 2008, 2011 para la acuicultura orgánica. Durante 180 días se suministraron dietas (levante: 27% PB y 4.120 cal/g EB; finalización: 21% PB y 4.200 cal/g EB formuladas con recursos provenientes de producción agrícola orgánica certificada. Se implementaron tres variables: un control sin fertilizante y dos diferentes niveles de fertilización con gallinaza orgánica (T1: Abonamiento intensivo con 5 g/m2 /día; T2: Abonamiento periódico con 14 g/m2 /semana y T3: Sin abonamiento. Se evaluó el efecto de los tratamientos sobre parámetros productivos: ganancia diaria de peso, conversión alimenticia aparente, tasa de crecimiento específico, rendimiento en filete, índices viscerosomático, hepatosomático y de grasa visceral, relación de eficiencia proteica, valor productivo de proteína y eficiencia de retención de energía. No se encontraron diferencias significativas en las variables evaluadas (p>0.05. Los resultados indican la posibilidad de implementar un sistema de alimentación orgánico como alternativa productiva que logra parámetros productivos que se aproximan a lo reportado para explotaciones convencionales de tilapia y con el potencial de posicionar un producto final en eco-mercados diferenciales siendo sustentable en su obtención.

Fatty acid concentration and proximate composition of acid silage from Nile tilapia (Oreochromis niloticus) waste, farmed in Indaiatuba – SP

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Sales, Ronaldo de Oliveira; Universidade Federal do Ceará; Park, Kil Jin; Universidade Estadual de Campinas; de Morais, Selene Maia; Universidade Estadual de Ceará

2013-01-01

This study was conducted to determine the composition and fatty acid profile of the Nile tilapia waste silage with the aim of investigating its nutritional potential. Four lots (5 kg each) of Nile tilapia waste was ground with 3% (w/w) formic acid, stored at 27°C room temperature for 90 days in polyethylene boxes with holes, through which gases went out and then the levels of moisture, protein, ash and total lipids were analyzed obtaining: 77.25, 16.31, 3.17 and 3.26% respectively. 22 types o...

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

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Imam Taufik

2013-06-01

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

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

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

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

2016-01-01

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

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

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

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.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

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.

Syncytial Hepatitis of Tilapia ( Oreochromis niloticus L.) is Associated With Orthomyxovirus-Like Virions in Hepatocytes.

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Del-Pozo, J; Mishra, N; Kabuusu, R; Cheetham, S; Eldar, A; Bacharach, E; Lipkin, W I; Ferguson, H W

2017-01-01

Using transmission electron microscopy (TEM), the presented work expands on the ultrastructural findings of an earlier report on "syncytial hepatitis," a novel disease of tilapia (SHT). Briefly, TEM confirmed the presence of an orthomyxovirus-like virus within the diseased hepatocytes but not within the endothelium. This was supported by observing extracellular and intracellular (mostly intraendosomal), 60-100 nm round virions with a trilaminar capsid containing up to 7 electron-dense aggregates. Other patterns noted included enveloped or filamentous virions and virion-containing cytoplasmic membrane folds, suggestive of endocytosis. Patterns atypical for orthymyxovirus included the formation of syncytia and the presence of virions within the perinuclear cisternae (suspected to be the Golgi apparatus). The ultrastructural morphology of SHT-associated virions is similar to that previously reported for tilapia lake virus (TiLV). A genetic homology was investigated using the available reverse transcriptase polymerase chain reaction (RT-PCR) probes for TiLV and comparing clinically sick with clinically normal fish and negative controls. By RT-PCR analysis, viral nucleic acid was detected only in diseased fish. Taken together, these findings strongly suggest that a virus is causally associated with SHT, that this virus shares ultrastructural features with orthomyxoviruses, and it presents with partial genetic homology with TiLV (190 nucleotides).

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

Analysis of potential risks from the bacterial communities associated with air-contact surfaces from tilapia (Oreochromis niloticus) fish farming.

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Grande Burgos, Maria Jose; Romero, Jose Luis; Pérez Pulido, Rubén; Cobo Molinos, Antonio; Gálvez, Antonio; Lucas, Rosario

2018-01-01

Tilapia farming is a promising growing sector in aquaculture. Yet, there are limited studies on microbiological risks associated to tilapia farms. The aim of the present study was to analyse the bacterial communities from solid surfaces in contact with air in a tilapia farm in order to evaluate the presence of bacteria potentially toxinogenic or pathogenic to humans or animals. Samples from a local tilapia farm (tank wall, aerator, water outlets, sink and floor) were analyzed by high throughput sequencing technology. Sequences were assigned to operational taxonomic units (OTUs). Proteobacteria was the main phylum represented in most samples (except for one). Cyanobacteria were a relevant phylum in the inner wall from the fattening tank and the wet floor by the pre-fattening tank. Bacteroidetes were the second phylum in relative abundance for samples from the larval rearing tank and the pre-fattening tank and one sample from the fattening tank. Fusobacteria showed highest relative abundances in samples from the larval rearing tank and pre-fattening tank. Other phyla (Verrucomicrobia, Actinobacteria, Firmicutes, Planktomycetes, Acidobacteria, Chloroflexi, Chlorobi, Gemmatiomonadetes or Fibrobacters) had lower relative abundances. A large fraction of the reads (ranging from 43.67% to 72.25%) were assigned to uncultured bacteria. Genus Acinetobacter (mainly A. calcoaceticus/baumanni) was the predominant OTU in the aerator of the fattening tank and also in the nearby sink on the floor. The genera Cetobacterium and Bacteroides showed highest relative abundances in the samples from the larval rearing tank and the pre-fattening tank. Genera including fish pathogens (Fusobacterium, Aeromonas) were only detected at low relative abundances. Potential human pathogens other than Acinetobacter were either not detected or had very low relative abundances (Acinetobacter and potential cyanotoxin-producing cyanobacteria. Copyright © 2017 Elsevier Inc. All rights reserved.

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

OpenAIRE

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

2017-01-01

Abstract 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 w...

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

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

2016-01-01

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

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

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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.

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

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.

Effect of methomyl on sex steroid hormone and vitellogenin levels in serum of male tilapia (Oreochromis niloticus) and recovery pattern.

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Meng, Shun-Long; Qiu, Li-Ping; Hu, Geng-Dong; Fan, Li-Min; Song, Chao; Zheng, Yao; Wu, Wei; Qu, Jian-Hong; Li, Dan-Dan; Chen, Jia-Zhang; Xu, Pao

2017-07-01

Tilapia were exposed to sub-lethal concentrations of 0, 0.2, 2, 20 or 200 μg/L for 30 days, then transferred to methomyl-free water for 18 days. E 2 , T, 11-KTand VTG in serum were examined. There were no significant changes in all the parameters in serum of tilapia exposed to 0.2 μg/L and 2 μg/L methomyl compared to the control. However, 20 μg/L and 200 μg/L have the potential to disrupt the endocrine system of male tilapia, as shown by its ability to increase VTG and E 2 and decrease T and 11-KT in serum. Thus it would appear the no observed adverse effect level for sexual steroid hormones of methomyl is lower than 2 μg/L. Recovery data showed that the effects produced by 20μg/L were reversible but not at 200μg/L. Furthermore, the sensitivity of above parameters to methomyl followed the order of VTG>E 2 >11-KT>T>GSI, suggesting VTG being the better biomarkers. © 2017 Wiley Periodicals, Inc.

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

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.

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

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Gonzales, John M.; Brown, Paul B.

Nile tilapia were evaluated as a bio-regenerative sub-process for reducing solid waste potentially encountered in bio-regenerative life support systems. Ten juvenile Nile tilapia (mean weight = 2.05 g) were stocked into triplicate aquaria and fed one of seven experimental diets consisting of vegetable, bacterial, or food waste for a period of seven weeks. Weight gain (g), specific growth rate (mg/d), and daily consumption (g) was significantly higher ( p diet (37.99 and 68.54, respectively) followed by fish fed the wheat bran/wheat germ diet (23.19 and 63.67, respectively). Nitrogen, sulfur, and crude protein retention was significantly higher ( p diet (23.68, 21.89, and 23.68, respectively). A general loss of minerals was observed among all groups. Strong associations were observed between crude lipid retention and sulfur retention ( r2 = 0.94), crude lipid retention and carbon retention ( r2 = 0.92), WG and fiber content of dietary treatments ( r2 = 0.92), WG and carbon retention and ( r2 = 0.88), WG and lysine content of waste residues ( r2 = 0.86), crude protein retention and carbon retention ( r2 = 0.84), sulfur retention and crude protein retention ( r2 = 0.84), and total sulfur amino acid (TSAA) content of residues and WG ( r2 = 0.81). Weaker associations existed between WG and crude lipid retention ( r2 = 0.77), crude fiber content and carbon retention ( r2 = 0.76), and WG and methionine content of waste residues ( r2 = 0.75). Additional research is needed to improve the nutritional quality of fibrous residues as a means to improve tilapia's ability to utilize these residues as a food source in bio-regenerative support systems.

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

CSIR Research Space (South Africa)

Zengeya, TA

2013-07-01

Full Text Available tilapia in its native and introduced ranges are not congruent. Nile tilapia exhibited broad invasive potential over most of southern Africa that overlaps the natural range of endemic congenerics. Of particular concern are areas which are free of exotic...

Effects of long term feeding of Quillaja saponins on sex ratio, muscle and serum cholesterol and LH levels in Nile tilapia (Oreochromis niloticus (L)).

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Francis, George; Levavi-Sivan, Berta; Avitan, Ayelet; Becker, Klaus

2002-12-01

Seventeen-day-old Nile tilapia fry were fed a standard diet (C) or diets containing 50-700 mg kg(-1) Quillaja saponin (QS) extract (groups S50, S150, S300, S500 and S700). After the first 8 weeks, 30 randomly selected tilapia from each of the treatments were placed in separate aquaria and fed the standard diet without saponins from then on (these were designated S50/C, S150/C, S300/C, S500/C and S700/C). The fish grew from an initial average weight of approximately 30 mg to a final average weight of 79 g during the 6-month feeding period. The difference between the average weight of C-fed tilapia and the treatment with the highest average weight after 6 months was 53.5%. The sex ratio of tilapia in the saponin-fed groups deviated from the normal 50:50 male:female ratio, with the S700 group showing a significantly higher number of males. Quillaja saponin stimulated LH release from dispersed tilapia pituitary cells in vitro. This effect was abolished in the presence of dilute calf serum. Serum LH values did not show any diet-dependent trend in either male or female tilapia in vivo. In both continuously saponin-fed and only-initially saponin-fed groups, the average serum (but not muscle) cholesterol levels in males showed an increasing trend (R(2) values of 0.62 and 0.69) with increasing dietary saponin level. It was concluded that dietary QS has the potential to change the sex-ratio in favour of males. More investigations are required to determine the mechanism of action and the optimum dietary level of QS for maximum effects.

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.

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

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2012-01-01

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

Pharmaceutical significance of Leuconostoc mesenteroides KS-TN11 isolated from Nile Tilapia, Oreochromis niloticus

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Bilal Ahmad Paray

2018-05-01

Full Text Available Aquatic animals are known for their myriad of beneficial bacteria with diverse biologically active compounds. The current study was aimed to isolate and characterize potentially beneficial lactic acid bacteria from Nile Tilapia and evaluate their pharmaceutical applications. The fish samples were dissected and stomach, intestine, and gills were collected and serially diluted for the isolation of lactic acid bacteria (LAB on BCP agar media. Identification of isolate was carried by biochemical and molecular characterization using API kit and 16S rRNA gene sequencing analysis, respectively. Further, KS-TN11 was assessed for α-glucosidase inhibitory potential using the chromogenic method. A lactic acid bacterium KS-TN11 was isolated from the stomach of Nile Tilapia and identified as Leuconostoc mesenteroides. Effect of KS-TN11 on lipid accumulation in adipocytes was done by using Oil Red O staining. The isolate showed strong antibacterial activity against a number of pathogenic bacteria in vitro. In addition, L. mesenteroides KS-TN11 KS-TN11 (50 mg/ml and 100 mg/ml tends to inhibit adipogenesis in 3T3-L1 adipocytes and thus may have possible anti-obesity effects. Moreover, L. mesenteroides KS-TN11 exhibited substantial α–glucosidase inhibitory activities by 41.33% at 50 mg/ml and 64% at 100 mg/ml, respectively. The bacterium showed potent antibacterial activity against a number of pathogenic bacteria; in addition to alpha-glucosidase activity, and inhibition of lipid accumulation in 3T3-L1 cell line. These results reinforce KS-TN11 as a novel bacterium with an impending pharmaceutical application. Keywords: Lactic acid bacteria, Antimicrobial, Fish microflora, Anti-diabetic

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

Effects of dietary Bacillus licheniformis on growth performance, immunological parameters, intestinal morphology and resistance of juvenile Nile tilapia (Oreochromis niloticus) to challenge infections.

Science.gov (United States)

Han, Biao; Long, Wei-Qing; He, Ju-Yun; Liu, Yong-Jian; Si, Yu-Qi; Tian, Li-Xia

2015-10-01

The effects of oral administration of Bacillus licheniformis on growth performance, immunity, intestinal morphology and disease resistance of juvenile tilapia were investigated. Six experimental diets supplemented with different concentrations of B. licheniformis (0%, 0.02%, 0.04%, 0.06%, 0.08% and 0.1% of AlCare(®), containing live germ 2 × 10(10) CFU/g) were formulated, viz. control, T1, T2, T3, T4 and T5. Each diet was randomly assigned to triplicate groups of 30 fishes (3.83 ± 0.03 g). After 10 weeks of feeding trial, weight gain (WG), final body wet weight (FBW) and specific growth rate (SGR) increased significantly in groups T2, T3, T4 and T5 compared with control and T1 (p 0.05). Compared with control, dietary B. licheniformis supplementation increased the content of complement C3 in serum significantly (P licheniformis supplementation (P > 0.05). When tilapia were challenged against Streptococcus iniae, survival rate improved significantly when tilapia fed with T2, T3, T4 and T5 (P licheniformis (T2, T3, T4, T5) tended to be regularly arranged and exhibited less exfoliation, twist and fusion. These results indicated that dietary supplementation of B. licheniformis not only increased the growth, immune response and disease resistance of juvenile tilapia, but also influenced anterior intestinal development and integrity. Furthermore, in our study, the optimal concentration of B. licheniformis in diets for tilapia was greater than or equal to 4.4 × 10(6) CFU/g. Copyright © 2015 Elsevier Ltd. All rights reserved.

Resource recovery from septic tank effluent using duckweed-based tilapia aquaculture.

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El-Shafai, Saber A; Abdel-Gawad, Fagr Kh; Samhan, Farag; Nasr, Fayza A

2013-01-01

Two parallel duckweed ponds were deployed to utilize nutrients from the effluent of a septic tank treating domestic wastewater. The effluent and fresh biomass of duckweed pond were fed to two subsequent fish ponds stocked with Nile tilapia (Oreochromis niloticus). Fish ponds receiving freshwater and commercial feed were used as control. The results of specific growth rate and feed conversion ratio showed no significant difference between the control ponds and treatment ponds. On the other hand, the total and net fish yields were significantly higher in the control. Microbial analysis revealed contamination of gills, intestine and liver of fish in the treatment ponds. The activity of the immune response genes was up-regulated in the brain and liver of the treatment samples. A micronucleus assay revealed a similar percentage of micronuclei in the polychromatic erythrocytes of blood in the control and treatment samples, while the treatment samples a had higher incidence of micronuclei in the polychromatic erythrocytes of gills, compared with the control.

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

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.

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.

Dietary Aloe vera improves plasma lipid profile, antioxidant, and hepatoprotective enzyme activities in GIFT-tilapia (Oreochromis niloticus) after Streptococcus iniae challenge.

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Gabriel, Ndakalimwe Naftal; Qiang, Jun; Ma, Xin Yu; He, Jie; Xu, Pao; Liu, Kai

2015-10-01

The current study investigated the effects of dietary Aloe vera on plasma lipid profile status, antioxidant, and hepatoprotective enzyme activities of GIFT-tilapia juveniles under Streptococcus iniae challenge. Five dietary groups were designed including a control and 100 % Aloe powder incorporated into a tilapia feed at 0.5, 1, 2, and 4 %/kg feed, which were administered for 8 weeks. Fish fed dietary Aloe at 4 %/kg feed significantly reduced in total cholesterol, while triacylglycerol reduced (P Aloe/kg feed compared to unsupplemented ones. High-density lipoprotein was significantly elevated in fish fed 0.5 and 1 % Aloe/kg feed compared to unsupplemented ones, and no significant changes (P > 0.05) were noted in low-density lipoprotein among test groups. Furthermore, high activities of superoxide dismutase, catalase, and glutathione peroxide in liver tissues were observed in Aloe-supplemented fish compared to unsupplemented ones, before and after S. iniae challenge (7.7 × 10(6) CFU cells/mL). Variations were also noted in malondialdehyde activity throughout the trial, but no significant difference (P > 0.05) was observed between groups. Meanwhile, Aloe-supplemented fish reduced serum aspartate and alanine aminotransferase (AST and ALT) activities before and after challenge. Based on the second-order polynomial regression analysis, dietary Aloe inclusion levels less than or equal to 1.88, 1.86, and 2.79 %/kg feed were determined to be suitable in improving plasma lipid profile status, antioxidant, and hepatoprotective enzyme activities in GIFT-tilapia in this study, respectively. Thus, A. vera extracts may be recommended as a tilapia feed supplement to enhance fish antioxidant and hepatoprotective capacities, especially during disease outbreaks.

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

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

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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

The effect of alginate incorporated in the ration on performance and handling of juvenile Nile tilapiaO efeito de alginatos incorporados `a ração sobre o desempenho produtivo e manejo de juvenis de tilápia do Nilo

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Leonardo Cericato

2011-07-01

Full Text Available The alginic acid is extracted from seaweed and when used in fish ration may induce immunomodulatory and immunostimulants responses. This study aimed to evaluate the effect of alginic acid incorporated in the ration on performance and handling of juvenile Nile tilapia, Oreochromis niloticus. The first phase of the experiment occurred in two excavated ponds earth. 57,000 juveniles were used for Nile tilapia, local strains with the average weight of 14 grams. The juvenile Nile tilapia received the experimental diet treated with ergosan at a dose of 1% of the diet. The survival rate of fish and feed conversion in the experimental Nile tilapia was higher than the control Nile tilapia. In the second stage 54,126 juveniles with average weight 40.63 grams, were used. These fish were transferred to 16 fish cages. There were no significant differences in mortality rate between treatments. The highest mortality occurred between the third and seventh days after the handling. The data confirm that the transfer of juvenile Nile tilapia in the ponds to fish cages is a strong stressor.Os ácidos algínicos são extraídos de algas marinhas e quando utilizados na dieta dos peixes podem induzir respostas imunomoduladoras e imunoestimulantes. Este trabalho teve o objetivo de avaliar o efeito dos alginatos incorporado na ração sobre o desempenho produtivo e manejo de juvenis de tilápia do Nilo, Oreochromis niloticus. A primeira fase do experimento ocorreu em dois viveiros escavados de terra. Foram utilizados 57.000 juvenis de tilápia do Nilo, variedade local com peso médio de 14 gramas. Os Juvenis do viveiro experimental receberam ração tratada com ergosan na dose de 1% da dieta. A taxa de sobrevivência dos peixes e a conversão alimentar dos peixes alojados no viveiro experimental foi superior ao daqueles alojados no viveiro controle. Na segunda fase foram utilizados 54.126 juvenis de 40,63 gramas. Estes peixes foram transferidos para 16 tanques-rede. N�

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

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 ...

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

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

2016-08-11

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

Cloning and primary immunological study of TGF-β1 and its receptors TβR I /TβR II in tilapia(Oreochromis niloticus).

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Zhan, Xu-liang; Ma, Tai-yang; Wu, Jin-ying; Yi, Li-yuan; Wang, Jing-yuan; Gao, Xiao-ke; Li, Wen-sheng

2015-07-01

The transforming growth factor β (TGF-β) superfamily plays critical roles in tumor suppression, cell proliferation and differentiation, tissue morphogenesis, lineage determination, cell migration and apoptosis. Recently, TGF-β1, one important member of TGF-β superfamily, is suggested as an immune regulator in the teleost. In this study, we cloned the cDNAs of TGF-β1 and its receptors, TβR I and TβR II (including three isoforms) from tilapia (Genbank accession numbers: KP754231- KP754235). A tissue distribution profile analysis indicated that TGF-β1 was highly expressed in the head kidney, gill, spleen, kidney and PBLs (peripheral blood leukocytes); TβR I only showed considerable expression in the liver; and TβR II-2 was highly expressed in the kidney, gill, liver, head kidney and heart. We determined that the mRNA expressions of TGF-β and TβR I /TβR II-2 were significantly increased in tilapia head kidney and spleen leukocytes by the stimulation of Lipopolysaccharide (LPS) or Poly I: C. We also examined their expressions in the spleen and head kidney of tilapia after IP injection of streptococcus agalactiae. The results showed that the mRNA expressions of these three genes all increased in the head kidney as early as 6 h post infection, and in the spleen 3 d post infection. In addition, the protein level of TGF-β1 was also up-regulated in the head kidney and the spleen after infection. Taken together, our data indicate that the TGF-β1-TβR I /TβR II-2 system functions potentially in tilapia immune system. Copyright © 2015 Elsevier Ltd. All rights reserved.

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

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

2000-01-01

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

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.

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 ...

A review of piscine islet xenotransplantation using wild-type tilapia donors and the production of transgenic tilapia expressing a "humanized" tilapia insulin.

Science.gov (United States)

Wright, James R; Yang, Hua; Hyrtsenko, Olga; Xu, Bao-You; Yu, Weiming; Pohajdak, Bill

2014-01-01

Most islet xenotransplantation laboratories have focused on porcine islets, which are both costly and difficult to isolate. Teleost (bony) fish, such as tilapia, possess macroscopically visible distinct islet organs called Brockmann bodies which can be inexpensively harvested. When transplanted into diabetic nude mice, tilapia islets maintain long-term normoglycemia and provide human-like glucose tolerance profiles. Like porcine islets, when transplanted into euthymic mice, they are rejected in a CD4 T-cell-dependent manner. However, unlike pigs, tilapia are so phylogenetically primitive that their cells do not express α(1,3)Gal and, because tilapia are highly evolved to live in warm stagnant waters nearly devoid of dissolved oxygen, their islet cells are exceedingly resistant to hypoxia, making them ideal for transplantation within encapsulation devices. Encapsulation, especially when combined with co-stimulatory blockade, markedly prolongs tilapia islet xenograft survival in small animal recipients, and a collaborator has shown function in diabetic cynomolgus monkeys. In anticipation of preclinical xenotransplantation studies, we have extensively characterized tilapia islets (morphology, embryologic development, cell biology, peptides, etc.) and their regulation of glucose homeostasis. Because tilapia insulin differs structurally from human insulin by 17 amino acids, we have produced transgenic tilapia whose islets stably express physiological levels of humanized insulin and have now bred these to homozygosity. These transgenic fish can serve as a platform for further development into a cell therapy product for diabetes. © 2014 The Authors. Xenotransplantation Published by John Wiley & Sons Ltd.

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 addition of tilapia Oreochromis niloticus and substrates for periphyton developments on pond ecology and production in C/N-controlled freshwater prawn Macrobrachium rosenbergii farming systems

NARCIS (Netherlands)

Asaduzzaman, M.; Wahab, M.A.; Verdegem, M.C.J.; Benerjee, S.; Akter, T.; Hasan, M.M.; Azim, M.E.

2009-01-01

The present research investigated the effect of addition of tilapia and substrates for periphyton development on pond ecology, production and economic performances in C/N controlled freshwater prawn farming system. The absence and presence (0 and 0.5 individual m- 2) of tilapia were investigated in

MICROBIOLOGICAL QUALITY AND SHELF LIFE OF FRESH PACKAGED TILAPIA FILLETS STORED UNDER DIFFERENT CHILL TEMPERATURES

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Odoli Cyprian

2013-02-01

Full Text Available Nile tilapia (Oreochromis niloticus farmed in recirculation aquaculture system (RAS was filleted and packaged in 100% air and 50% CO2: 50% N2 modified atmosphere (MA prior to storage at 1˚C and -1˚C for up to 27 days. Fillets were sampled regularly and analysed for headspace gas composition, sensory and microbial changes. Shelf life varied with apparent relation to storage temperature, package atmosphere and microflora. Pseudomonads were reported as the main spoilage organisms in tilapia fillets during chilled storage conditions. Sensory analysis of cooked samples as well as microbial growth indicated fillets packaged in 100% air had a shelf life of 13-15 days during storage at 1˚C and 20 days at -1˚C. At the end of shelf life in 100% air packaged groups, TVC and pseudomonads counts reached log 7 colony-forming units g-1 in flesh. Whereas in 50% CO2: 50% N2 packaged fillets, the lag phase and generation time of bacteria was extended and recorded counts of < log 4 colony-forming units g-1 up to 27 days of storage at both 1˚C and -1˚C. However, 50% CO2 : 50% N2 conditions restricted fillets shelf life to 23 days based on sensorial changes mainly fillets colour characteristics.

Effect of smoking on Polycyclic Aromatic Hydrocarbons (PAHS ...

African Journals Online (AJOL)

The effects of smoking on proximate composition, energy values and concentrations of polycyclic aromatic hydrocarbons (PAHs) were studied in raw and smoked samples of catfish (Clarias gariepinus) and tilapia (Oreochromis niloticus). Crude protein was higher in the tilapia sample for both raw and smoked samples.

BICULTIVO EN BIOFLOC DE CACHAMA BLANCA -Piaractus brachypomus- Y TILAPIA NILÓTICA -Oreochromis niloticus- ALIMENTADAS CON DIETAS DE ORIGEN VEGETAL

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S. B. Brú-Cordero

2017-01-01

Full Text Available Se evaluó el desempeño productivo de cachama blanca y tilapia nilótica cultivadas en biofloc y alimentadas con dietas de origen vegetal. Se cultivaron 80 peces/m3 en proporción 1:1 (cachama : tilapia, con tres niveles de proteína bruta (PB: 16% (T16, 24% (T24 y 32% (T32, en tanques de 1.000 l, con aireación permanente durante 120 días. Se estimaron parámetros de crecimiento, rendimiento, calidad de agua, costos de producción y análisis proximal de los flóculos. El oxígeno disuelto se mantuvo con saturación por encima de 100% y los compuestos nitrogenados (NO2 = 0,4-0,5 mg/l, NO3 = 0,4-0,5 mg/l, NH3 = 0,2-0,3 mg/l, TAN = 2,2-2,4 mg/l no presentaron diferencias entre los tratamientos (P > 0,05. Los pesos finales de la cachama (173,5-196,2 g fueron entre dos y cuatro veces los obtenidos por la tilapia (43,0-87,9 g. El mejor rendimiento del bicultivo se obtuvo con la dieta T24 (11,4 ± 1,3 kg/m3, el cual también registró el menor FCA (0,9 ± 0,3. Producir un kilogramo de pescado costó entre COP $3.148 (T24 y COP $4.445 (T32; del cual el alimento representó entre 49,2% (T16 y 63,3% (T32 y la energía, entre 10,3% (T32 y 14,2% (T16 de los costos. El análisis proximal de los flóculos registró niveles de proteína bruta (29-36% PB adecuados para cachama y tilapia; pero con niveles bajos de lípidos (< 1,0%. El desempeño productivo y los costos de producción permiten sugerir la viabilidad que ofrece el sistema biofloc para la producción de carne de pescado con alimento de 24% PB de origen vegetal.

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

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.

Fatty acid composition of muscle and heart tissue of Nile perch ...

African Journals Online (AJOL)

The fatty acid composition in the heart tissue and muscle tissue of the Nile perch, Lates niloticus, and Nile tilapia, Oreochromis niloticus populations from Lakes Kioga and Victoria was determined by methanolysis and gas chromatography of the resulting fatty acid methyl esters. The analytical data were treated by ...

GROWTH ENHANCEMENT, SURVIVAL AND DECREASE OF ECTOPARASITIC INFECTIONS IN MASCULINIZED NILE TILAPIA FRY IN A RECIRCULATING AQUACULTURE SYSTEM

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Isabel Jiménez García

2012-11-01

Full Text Available Under lab conditions, tilapia fry at culture densities of 8 fish/L-1 can reach a body weight of 0.5 to 1.0 g after the masculinization phase. In commercial hatcheries, the stocking density is four to six times higher, and consequently the occurrence of ectoparasitic infections also rises. The aim of this study was to examine the growth and survival of masculinized Nile tilapia (Oreochromis niloticus fry in a recirculating aquaculture system (RAS. The fry, which were naturally parasitized by protozoan of the genera Trichodina, Ambiphrya and Chilodonella, weighed 0.013 ± 0.003 g and were reared in replicated tanks (N = 3 during 32 days at density of 18 fish/L-1 in the RAS to maintain good water quality, which was achieved especially during the first 22 days of fish rearing. The infection parameters and growth were monitored twice a week. The final fish weight was 1.17 ± 0. 6 g and survival 99.5%. The most frequent parasites were Trichodina and Gyrodactylus cichlidarum (Monogenea. Although nitrogen compounds increased significantly over the last 10 days of fry rearing, final growth and survival were higher than those reported, additionally, the ectoparasitic infections were relatively low.

A review of piscine islet xenotransplantation using wild-type tilapia donors and the production of transgenic tilapia expressing a “humanized” tilapia insulin

Science.gov (United States)

Wright, James R; Yang, Hua; Hyrtsenko, Olga; Xu, Bao-You; Yu, Weiming; Pohajdak, Bill

2014-01-01

Most islet xenotransplantation laboratories have focused on porcine islets, which are both costly and difficult to isolate. Teleost (bony) fish, such as tilapia, possess macroscopically visible distinct islet organs called Brockmann bodies which can be inexpensively harvested. When transplanted into diabetic nude mice, tilapia islets maintain long-term normoglycemia and provide human-like glucose tolerance profiles. Like porcine islets, when transplanted into euthymic mice, they are rejected in a CD4 T-cell-dependent manner. However, unlike pigs, tilapia are so phylogenetically primitive that their cells do not express α(1,3)Gal and, because tilapia are highly evolved to live in warm stagnant waters nearly devoid of dissolved oxygen, their islet cells are exceedingly resistant to hypoxia, making them ideal for transplantation within encapsulation devices. Encapsulation, especially when combined with co-stimulatory blockade, markedly prolongs tilapia islet xenograft survival in small animal recipients, and a collaborator has shown function in diabetic cynomolgus monkeys. In anticipation of preclinical xenotransplantation studies, we have extensively characterized tilapia islets (morphology, embryologic development, cell biology, peptides, etc.) and their regulation of glucose homeostasis. Because tilapia insulin differs structurally from human insulin by 17 amino acids, we have produced transgenic tilapia whose islets stably express physiological levels of humanized insulin and have now bred these to homozygosity. These transgenic fish can serve as a platform for further development into a cell therapy product for diabetes. PMID:25040337

Time related alterations in digestibility and faecal characteristics as affected by dietary composition in the Nile tilapia (Oreochromis niloticus L.)

NARCIS (Netherlands)

Amirkolaie, A.K.; Schrama, J.W.

2015-01-01

After being shifted to a new diet, time related alterations in digestibility, faecal waste production and faeces recovery in Nile tilapia were assessed in relation with dietary ingredient composition. Four experimental diets were formulated according to a 2 by 2 factorial design: two starch

Oxidative stress biomarkers in Oreochromis niloticus as early ...

African Journals Online (AJOL)

... in Oreochromis niloticus as early warning signals in assessing pollution from ... in comparison to control fish, can be used to assess river water quality using O. niloticus. ... Concentrations of zinc, cadmium, chromium, nickel, lead, copper, ...

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

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.

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 ...

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

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Silia Maria de Negreiros Sousa

2013-08-01

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

Physical stability and clinical efficacy of Crocodylus niloticus oil lotion

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Telanie Venter

Full Text Available ABSTRACT The stability and the anti-ageing, skin hydrating and anti-erythema effects of a commercialized Crocodylus niloticus Laurenti, 1768, Crocodylidae, oil lotion was determined. The lotion was stored at controlled conditions over six months during which several stability tests were performed. For the clinical efficacy studies lotion was applied on volar forearm skin (female volunteers and compared to a liquid paraffin-containing reference product. Skin hydrating and anti-ageing effects were determined with a Corneometer®, Cutometer® and Visioscan®, following single (3 h and multiple applications (12 weeks. The Vapometer® and Mexameter® were utilized to determine this lotion's anti-erythema effects on sodium lauryl sulfate irritated skin. The lotion demonstrated good stability over 6 months. The reference product increased skin hydration and decreased skin wrinkles to a larger extent than the C. niloticus lotion after a single application, whereas the C. niloticus lotion decreased skin scaliness better than the reference product. During the long-term study, the reference product overall increased skin hydration more than the C. niloticus lotion, whereas C. niloticus lotion increased skin elasticity to a larger extent than the reference product. C. niloticus lotion increased skin wrinkles and decreased skin scaliness over 12 weeks. Compared to non-treated, irritated skin, C. niloticus lotion demonstrated some potential anti-inflammatory characteristics.

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.

Oreochromis niloticus

African Journals Online (AJOL)

Effect of diets containing cocoa bean shell and coconut oil cake on the growth of Oreochromis niloticus (LINNE, 1758) in pond. Yacouba BAMBA 1*, N'Golo OUATTARA 2, Siaka OUATTARA 2,. Allassane OUATTARA 1 and Germain GOURENE 1. 1 Laboratoire d'Environnement et de Biologie Aquatique (LEBA), UFR des ...

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 ...

Development of a quantitative PCR assay for monitoring Streptococcus agalactiae colonization and tissue tropism in experimentally infected tilapia.

Science.gov (United States)

Su, Y-L; Feng, J; Li, Y-W; Bai, J-S; Li, A-X

2016-02-01

Streptococcus agalactiae has become one of the most important emerging pathogens in the aquaculture industry and has resulted in large economic losses for tilapia farms in China. In this study, three pairs of specific primers were designed and tested for their specificities and sensitivities in quantitative real-time polymerase chain reactions (qPCRs) after optimization of the annealing temperature. The primer pair IGS-s/IGS-a, which targets the 16S-23S rRNA intergenic spacer region, was finally chosen, having a detection limit of 8.6 copies of S. agalactiae DNA in a 20 μL reaction mixture. Bacterial tissue tropism was demonstrated by qPCR in Oreochromis niloticus 5 days post-injection with a virulent S. agalactiae strain. Bacterial loads were detected at the highest level in brain, followed by moderately high levels in kidney, heart, spleen, intestines, and eye. Significantly lower bacterial loads were observed in muscle, gill and liver. In addition, significantly lower bacterial loads were observed in the brain of convalescent O. niloticus 14 days post-injection with several different S. agalactiae strains. The qPCR for the detection of S. agalactiae developed in this study provides a quantitative tool for investigating bacterial tissue tropism in infected fish, as well as for monitoring bacterial colonization in convalescent fish. © 2015 John Wiley & Sons Ltd.

Effects of water physico-chemical parameters on tilapia (Oreochromis niloticus growth in earthen ponds in Teso North Sub-County, Busia County

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Agano J. Makori

2017-11-01

Full Text Available Abstract Small-scale fish farmers in developing countries are faced with challenges owing to their limited information on aquaculture management. Nile tilapia farmers in Teso North Sub-County recorded lower yields than expected in 2009 despite having been provided with required inputs. Water quality was suspected to be the key factor responsible for the low yields. This study sought to assess the effects of earthen pond water physico-chemical parameters on the growth of Nile tilapia in six earthen fish ponds under semi-intensive culture system in Teso North Sub-County. The study was longitudinal in nature with pond water and fish being the units of analysis. Systematic sampling was used to select five ponds while a control pond was purposively selected based on its previously high harvest. Four ponds were fed by surface flow and two by underground water. Each pond was fertilized and stocked with 900 fry of averagely 1.4 g and 4.4 cm. Physico-chemical parameters were measured in-situ using a multi-parameter probe. Sixty fish samples were randomly obtained from each pond fortnightly for four months using a 10 mm mesh size and measured, weighed and returned into the pond. Mean range of physico-chemical parameters were: dissolved oxygen (DO 4.86–10.53 mg/l, temperature 24-26 °C, pH 6.1–8.3, conductivity 35–87 μS/cm and ammonia 0.01–0.3 mg/l. Temperature (p = 0.012 and conductivity (p = 0.0001 levels varied significantly between ponds. Overall Specific Growth Rate ranged between 1.8% (0.1692 g/day and 3.8% (1.9 g/day. Ammonia, DO and pH in the ponds were within the optimal levels for growth of tilapia, while temperature and conductivity were below optimal levels. As temperature and DO increased, growth rate of tilapia increased. However, increase in conductivity, pH and ammonia decreased fish growth rate. Temperature and DO ranging between 27 and 30 °C and 5–23 mg/l, respectively, and SGR of 3.8%/day and above are

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.

Evaluation of the technological quality presented for a canned Nile tilapia (Oreochromis niloticusAvaliação da qualidade tecnológica apresentada por tilápia do Nilo (Oreochromis niloticus enlatada

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Cleonice Sarmento

2012-05-01

Full Text Available The fish is quite sensitive to the deterioration due to the high activity of water and, especially to a near pH of the neutrality. The application of the heat needs a rigorous control of time and temperature. The objective of this work developed meat of tilapia canned in vegetable edible oil, for the use from the nonstandard raw material, in order to offer a product with high collected value. The meat of tilapia were taken to the daily pay-cooking in fluent steam for approximately 50 minutes, when the oil of covering was next added, when re-drove and been subdued to two thermal treatments respectively of 15 and 30 minutes in autoclave 121°C. After that the microbiological analyses were carried out, chemical-physically and sensory. The microbiological evaluation showed that the products were presenting satisfactory conformable quality to legislation. The pickles of tilapia presented next composition centesimal: moisture 48.4 %; ashes 3.1 %; protein 12.2 %; lipids 32.7 %; chloride 0.8 %. The sensory analysis showed what, did not exist significant difference at the level of 5 % in the different treatments. The test of commercial sterility was carried out also, where two thermal treatments were adapted to maintain the quality of the pickle of tilapia canned. It was ended that, the pickles of tilapia, they presented quality compatible with similar products, confirming the viability of production of this product. O objetivo deste trabalho foi avaliar microbiologicamente, físico-quimicamente e sensorialmente uma conserva de tilápia enlatada em óleo vegetal comestível, aproveitando matéria-prima fora do padrão, a fim de oferecer um produto com alto valor agregado. As conservas de tilápia foram levadas a pré-cozimento em vapor fluente por aproximadamente 50 minutos, em seguida adicionado o óleo de cobertura, recravadas e submetidas a dois tratamentos térmicos respectivamente de 15 e 30 minutos em autoclave a 121°C. Após isso foram realizadas

Changes in the photosynthetic activity of Microcystis colonies after gut passage through Nile tilapia (Oreochromis niloticus) and silver carp (Hypophthalmichthys molitrix)

Czech Academy of Sciences Publication Activity Database

Jančula, Daniel; Míkovcová, M.; Adámek, Z.; Maršálek, Blahoslav

2008-01-01

Roč. 39, č. 3 (2008), s. 311-314 ISSN 1355-557X R&D Projects: GA MŠk 1M0571 Institutional research plan: CEZ:AV0Z60050516 Keywords : Tilapia * cyanobacteria * silver carp Subject RIV: EF - Botanics Impact factor: 0.991, year: 2008

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 ...

Growth rates of alien Oreochromis niloticus and indigenous ...

African Journals Online (AJOL)

Growth rates of indigenous Oreochromis mortimeri and alien Oreochromis niloticus from Lake Kariba were estimated from samples collected in 1997–2000, 2003–2005 and 2010–2011. Growth zones on scales and otoliths of O. niloticus and on the otoliths and opercula of O. mortimeri were deposited annually.

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

Science.gov (United States)

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.

Producción de tilapia nilótica (Oreochromis niloticus L. utilizando hojas de chaya (Cnidoscolus chayamansa McVaugh como sustituto parcial del alimento balanceado Nile tilapia production (Oreochromis niloticus L. using tree spinach leaves (Cnidoscolus chayamansa McVaugh as a partial substitute for balanced feed

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Gaspar R Poot-López

2012-11-01

Full Text Available La acuicultura es una alternativa para la producción de proteína de alta calidad a bajo precio, particularmente en países en desarrollo y desabasto de alimentos. En zonas rurales, la disponibilidad de insumos alternativos es clave para mejorar la producción en el cultivo de peces, sobre todo si dichos insumos se usan en forma cruda. Una opción son las hojas de chaya (Cnidoscolus chayamansa, arbusto que crece en México, Centroamérica y Sudamérica. En este estudio se evaluó durante dos épocas climáticas (cálida y fría la supervivencia, tasa de crecimiento y tasa de conversión alimenticia de juveniles de tilapia (7-4,5 g, al sustituir parcialmente la ración de alimento balanceado (25 y 50% con hojas crudas de chaya (ad libitum, en un diseno experimental completamente al azar, con dos tratamientos y un control (00% de la ración a base de alimento balanceado, con tres réplicas cada uno por época climática. Las densidades fueron de 36 peces m-3 por réplica en la época fría y de 44 peces m-3 por réplica en la época cálida. Los resultados indican que los tratamientos con 50 y 75% de alimento balanceado y chaya, en ambas épocas climáticas, tuvieron una ganancia de peso similar a la de los organismos que se alimentaron con la dieta control. Durante la época fría se observaron efectos adversos en la supervivencia, peso ganado y tasa de conversión alimenticia en todos los tratamientos, lo cual no ocurrió en la época cálida. Al incluir hojas de chaya en la dieta de las tilapias, la tasa de conversión alimenticia de alimento balanceado se redujo de 9,7 a 33,62% en la época fría y de 5,38 a 40,23% en la época cálida. Los resultados muestran que el uso de insumos complementarios disponibles regionalmente como la chaya, puede favorecer el desarrollo de cultivos de tilapia a pequena escala en los trópicos.Aquaculture is an alternative for the production of high-quality, low-cost protein, particularly in developing countries

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

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Ruchi Singh

2012-01-01

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

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.

Dietary probiotic supplementation improves growth and the intestinal morphology of Nile tilapia.

Science.gov (United States)

Ramos, M A; Batista, S; Pires, M A; Silva, A P; Pereira, L F; Saavedra, M J; Ozório, R O A; Rema, P

2017-08-01

Probiotic administration can be a nutritional strategy to improve the immune response and growth performance of fish. The current study aimed to evaluate the effects of a probiotic blend (Bacillus sp., Pediococcus sp., Enterococcus sp., Lactobacillus sp.) as a dietary supplement on growth performance, feed utilization, innate immune and oxidative stress responses and intestinal morphology in juvenile Nile tilapia (Oreochromis niloticus). The probiotic was incorporated into a basal diet at three concentrations: 0 g/kg (A0: control), 3 g/kg (A1: 1.0×106 colony forming unit (CFU)/g) and 6 g/kg (A2: 2.3×106 CFU/g diet). After 8 weeks of probiotic feeding, weight and specific growth rate where significantly higher in fish-fed A1 diet than in fish-fed A0. Alternative complement in plasma was significantly enhanced in fish-fed A2 when compared with A0. The hepatic antioxidant indicators were not affected by probiotic supplementation. Villi height and goblet cell counts increased significantly in the intestine of fish-fed A1 and A2 diets compared with A0. The dietary probiotic supplementation was maintained until 20 weeks of feeding. Then the selected immune parameters, digestive enzymes and apparent digestibility of diets were studied. No effect of probiotic feeding was observed after that longer period supplementation. The dietary supplementation of mixed species probiotic may constitute a valuable nutritional approach towards a sustainable tilapia aquaculture. The improvement of the immune responses and intestinal morphology play an important role in increasing growth performance, nutrient absorption and disease resistance in fish, important outcomes in such a competitive and developing aquaculture sector.

Partial Replacement of soybean cake with amaranthus spinosus leaf meal in the diet of nile tilapia (oreochromis niloticus)

International Nuclear Information System (INIS)

Adeniji, C.A.; Fakoya, K.A.; Omamohwo, V.R.

2007-01-01

The study, designed to assess the potentials of oven dried Amaranthus spinosus leaf meal as partial replacement for soybean cake in the diet of Nile Tilapia, revealed no significant difference (P>0.05) in feed and protein intake. Fish fed on Amaranthus spinosus leaf meal diets had significant (P<0.05) higher survival percentage, while that on soybean cake meal (control diet) recorded significant (P<0.05) better weight gain, average daily rate of growth, efficient feed and protein utilization as well as average final weight. (author)

Incorporation and profile of fatty acids in tilapia fillets (Oreochromis niloticus fed with tung oil

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Elton Guntendorfer Bonafé

2013-02-01

Full Text Available The acceptance of tung oil enriched diet and the incorporation of conjugated linolenic acid - CLnA into fillets of Genetically Improved Farmed Tilapia (GIFT were investigated. The diet was well accepted, and after 10 days CLnA was incorporated into the fillets with a 1.02% content of total fatty acids (FA. In addition, biosynthesis of the conjugated linoleic acid isomers - CLA (0.31% of fillet total FA content from CLnA, and the presence of alpha-linolenic acid - LNA (1.08% of fillet total FA content, eicosapentaenoic acid - EPA (2.85% of fillet total FA content and docosahexaenoic acid - DHA (3.08% of fillet total FA content were observed. Therefore, the consumption of this fish can increase the intake of different FA (CLnA, CLA, LNA, EPA and DHA, which play an important role in human metabolism.

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.

Potential contribution of fish feed and phytoplankton to the content of volatile terpenes in cultured Pangasius (Pangasianodon hypophthalmus) and Tilapia (Oreochromis niloticus)

DEFF Research Database (Denmark)

Podduturi, Raju; Petersen, Mikael Agerlin; Mahmud, Sultan

2017-01-01

Geosmin and 2-methylisoborneol are the most recognized off-flavors in freshwater fish, but terpenes may also contribute off-flavor in fish. We identified six monoterpenes, 11 sesquiterpenes, and three terpene-related compounds in pangasius and tilapia from aquaculture farms in Bangladesh. The con...

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.

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.

Synchronization to light and mealtime of daily rhythms of locomotor activity, plasma glucose and digestive enzymes in the Nile tilapia (Oreochromis niloticus).

Science.gov (United States)

Guerra-Santos, Bartira; López-Olmeda, José Fernando; de Mattos, Bruno Olivetti; Baião, Alice Borba; Pereira, Denise Soledade Peixoto; Sánchez-Vázquez, Francisco Javier; Cerqueira, Robson Bahia; Albinati, Ricardo Castelo Branco; Fortes-Silva, Rodrigo

2017-02-01

The light-dark cycle and feeding can be the most important factors acting as synchronizers of biological rhythms. In this research we aimed to evaluate synchronization to feeding schedule of daily rhythms of locomotor activity and digestive enzymes of tilapia. For that purpose, 120 tilapias (65.0±0.6g) were distributed in 12 tanks (10 fish per tank) and divided into two groups. One group was fed once a day at 11:00h (zeitgeber time, ZT6) (ML group) and the other group was fed at 23:00h (ZT18) (MD group). The fish were anesthetized to collect samples of blood, stomach and midgut at 4-hour intervals over a period of 24h. Fish fed at ML showed a diurnal locomotor activity (74% of the total daily activity occurring during the light phase) and synchronization to the feeding schedule, as this group showed anticipation to the feeding time. Fish fed at MD showed a disruption in the pattern of locomotor activity and became less diurnal (59%). Alkaline protease activity in the midgut showed daily rhythm with the achrophase at the beginning of the dark phase in both ML and MD groups. Acid protease and amylase did not show significant daily rhythms. Plasma glucose showed a daily rhythm with the achrophase shifted by 12h in the ML and MD groups. These results revealed that the feeding time and light cycle synchronize differently the daily rhythms of behavior, digestive physiology and plasma metabolites in the Nile tilapia, which indicate the plasticity of the circadian system and its synchronizers. Copyright © 2016 Elsevier Inc. All rights reserved.

Metallomic study on plasma samples from Nile tilapia using SR-XRF and GFAAS after separation by 2D PAGE: Initial results

International Nuclear Information System (INIS)

Santos, F.A.; Lima, P.M.; Neves, R.C.F.; Moraes, P.M.; Castro, G.R.; Padilha, P.M.; Perez, C.A.; Silva, M.O.A.; Arruda, M.A.Z.

2011-01-01

An investigation was made on plasma samples obtained after protein separation. The proteome of the plasma of Nile tilapia (Oreochromis niloticus) was separated by 2D PAGE, and manganese and zinc in protein spots was qualitatively and quantitatively determined by synchrotron radiation X-ray fluorescence (SR-XRF) and graphite furnace atomic absorption spectrometry (GFAAS). Manganese and zinc are present in four and six plasma protein spots, respectively. These ions are bound to proteins with molecular weights ranging from 19 to 70 kDa and with isoelectric point (pI) ranging from 4.7 to 6.3. The concentrations of manganese and zinc bound to these proteins as determined by GFAAS following acid digestion of the spots range from 0.8 to 2.6 mg of manganese, and from 1.0 to 6.3 mg of zinc, respectively, per g of protein. (author)

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

Tilapia culture in Kuwait: constraints and solutions

OpenAIRE

Ridha, M.T.

2006-01-01

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

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

Science.gov (United States)

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.

Nile tilapia culture on domestic effluent treated in stabilization ponds.

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Clovis Matheus Pereira

2009-03-01

Full Text Available The performance and filet quality of tilapias (Oreochromis niloticus culture in effluent stabilization lagoons was tested at the densities of 3 fish/m2 (T3, 7 fish/m2 (T2 and 7 fish/m2 in clean water + diet (T1 with 3 repetitions in tanks of 2.57m2 and 0.60m of water column with supplemental aeration. Fish culture in clean water plus diet (T1 presented the highest growth. The higher density T3 (7/m2 compared to T2 (3/m2 did not result in any difference of total production (p > 0.05 but this was compensated by the increased individual fish growth rate at lower density. The conditions that sustain fish survival culture with ETE effluent were attested by the high survival (> 90% under both treatments, but only 10% of the water samples from T2 and T3 N-total ammonium was favorable for fish growth (< 2.0mg/L. The rearing system improved the effluent quality, reducing the total organic nitrogen and the solids in suspension. The faecal coliforms, Salmonella sp. and Staphylococcus aureus from the effluent and fish were verified to be within the standards laid down by the World Health Organization (WHO.

Influence of technological treatments on bacterial communities in ...

African Journals Online (AJOL)

Influence of technological treatments on bacterial communities in tilapia ( Oreochromis niloticus ) as determined by 16S rDNA fingerprinting using polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE)

Multiresidue Method for Quantification of Sulfonamides and Trimethoprim in Tilapia Fillet by Liquid Chromatography Coupled to Quadrupole Time-of-Flight Mass Spectrometry Using QuEChERS for Sample Preparation.

Science.gov (United States)

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

2018-01-01

A multiresidue method for detecting and quantifying sulfonamides (sulfapyridine, sulfamerazine, sulfathiazole, sulfamethazine, sulfadimethoxine, sulfamethoxazole, and sulfamethoxypyridazine) and trimethoprim in tilapia fillet ( Oreochromis niloticus ) using liquid chromatography coupled to mass spectrometry was developed and validated. The sample preparation was optimized using the QuEChERS approach. The chromatographic separation was performed using a C18 column and 0.1% formic acid in water and acetonitrile as the mobile phase in the isocratic elution mode. Method validation was performed based on the Commission Decision 2002/657/EC and Brazilian guideline. The validation parameters evaluated were linearity ( r  ≥ 0.99); limits of detection (LOD) and quantification (LOQ), 1 ng·g -1 and 5 ng·g -1 , respectively; intraday and interdays precision (CV lower than 19.4%). The decision limit (CC α 102.6-120.0 ng·g -1 and 70 ng·g -1 for sulfonamides and trimethoprim, respectively) and detection capability (CC β 111.7-140.1 ng·g -1 and 89.9 ng·g -1 for sulfonamides and trimethoprim, respectively) were determined. Analyses of tilapia fillet samples from fish exposed to sulfamethazine through feed (incurred samples) were conducted in order to evaluate the method. This new method was demonstrated to be fast, sensitive, and suitable for monitoring sulfonamides and trimethoprim in tilapia fillet in health surveillance programs, as well as to be used in pharmacokinetics and residue depletion 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

Outbreaks of Tilapia Lake Virus Infection, Thailand, 2015-2016.

Science.gov (United States)

Surachetpong, Win; Janetanakit, Taveesak; Nonthabenjawan, Nutthawan; Tattiyapong, Puntanat; Sirikanchana, Kwanrawee; Amonsin, Alongkorn

2017-06-01

During 2015-2016, several outbreaks of tilapia lake virus infection occurred among tilapia in Thailand. Phylogenetic analysis showed that the virus from Thailand grouped with a tilapia virus (family Orthomyxoviridae) from Israel. This emerging virus is a threat to tilapia aquaculture in Asia and worldwide.

Outbreaks of Tilapia Lake Virus Infection, Thailand, 2015?2016

OpenAIRE

Surachetpong, Win; Janetanakit, Taveesak; Nonthabenjawan, Nutthawan; Tattiyapong, Puntanat; Sirikanchana, Kwanrawee; Amonsin, Alongkorn

2017-01-01

During 2015?2016, several outbreaks of tilapia lake virus infection occurred among tilapia in Thailand. Phylogenetic analysis showed that the virus from Thailand grouped with a tilapia virus (family Orthomyxoviridae) from Israel. This emerging virus is a threat to tilapia aquaculture in Asia and worldwide.

Digestibilidade aparente de ingredientes do Semi-Árido Nordestino para tilápia do Nilo Apparent digestibility of ingredients of the Northeast Semi-Arid for Nile tilapia

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Josivânia Rodrigues de Araújo

2012-05-01

Full Text Available O experimento avaliou o coeficiente de digestibilidade aparente (CDA da matéria seca (MS, energia bruta (EB, extrato etéreo (EE e proteína bruta (PB de ingredientes do Semi-Árido Nordestino: farinhas do feno de maniçoba (FM, do feno de leucena (FL e do feno da folha de mandioca (FFM, raspa de mandioca (RM e resíduos de vitivinícola (RV para tilápia do Nilo (Oreochromis niloticus. Os CDA para a MS, EB, EE e PB foram de 20,74%, 30,30%, 48,36% e 71,72% para FL; 19,34%, 17,08%, 30,03% e 44,88% para FM; 30,32%, 23,04%, 4,43% e 21,07% para FFM; 72,85%, 70,62%, 81,78% e 84,51% para RM e de 33,38%, 50,80%, 79,39% e 67,25% para RV. O feno de leucena, a raspa de mandioca e os resíduos de vitivinícola são promissores para a formulação de rações. A utilização dos ingredientes testados na composição de rações artesanais ou comercias para a tilápia do Nilo, bem como os níveis seguros para a inclusão destes devem ser testados.The experiment evaluated the apparent digestibility coefficient (CDA of dry matter (DM, gross energy (GE, ether extract (EE and crude protein (CP of regional alternative ingredients of Semi-arid Northeast as flour of maniçoba hay (FM, of Leucaena hay (FL and of cassava leaves (FFM, as well as cassava scrapings (RM and residues of wine (RV for Nile tilapia (Oreochromis niloticus. CDA for DM, GE, EE and CP were 20.74%, 30.30%, 48.36% and 71.72% for FL, 19.34%, 17.08%, 30.03% and 44.88% for FM, 30.32%, 23.04%, 4.43% and 21.07% for FFM, 72.85%, 70.62%, 81.78% and 84.51% for RM and 33.38%, 50.80%, 79.39% and 67.25% for RV. The leucaena hay, the cassava scrapings and residues of wine are promising for the formulation of diets for Nile tilapia. However, the use of tested ingredients in commercial and homemade diets to Nile tilapia, as well as the safe inclusion levels of these should be tested.

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

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

Dietary nutrient composition affects digestible energy utilisation for growth: a study on Nile tilapia (Oreochromis niloticus) and a literature comparison across fish species

NARCIS (Netherlands)

Schrama, J.W.; Subramanian, S.; Geurden, I.; Heinsbroek, L.T.N.; Kaushik, S.J.; Verreth, J.A.J.

2012-01-01

The effect of the type of non-protein energy (NPE) on energy utilisation in Nile tilapia was studied, focusing on digestible energy utilisation for growth (kgDE). Furthermore, literature data on kgDE across fish species were analysed in order to evaluate the effect of dietary macronutrient

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

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Stephan Wessels

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

Copy Number Variations in Tilapia Genomes.

Science.gov (United States)

Li, Bi Jun; Li, Hong Lian; Meng, Zining; Zhang, Yong; Lin, Haoran; Yue, Gen Hua; Xia, Jun Hong

2017-02-01

Discovering the nature and pattern of genome variation is fundamental in understanding phenotypic diversity among populations. Although several millions of single nucleotide polymorphisms (SNPs) have been discovered in tilapia, the genome-wide characterization of larger structural variants, such as copy number variation (CNV) regions has not been carried out yet. We conducted a genome-wide scan for CNVs in 47 individuals from three tilapia populations. Based on 254 Gb of high-quality paired-end sequencing reads, we identified 4642 distinct high-confidence CNVs. These CNVs account for 1.9% (12.411 Mb) of the used Nile tilapia reference genome. A total of 1100 predicted CNVs were found overlapping with exon regions of protein genes. Further association analysis based on linear model regression found 85 CNVs ranging between 300 and 27,000 base pairs significantly associated to population types (R 2  > 0.9 and P > 0.001). Our study sheds first insights on genome-wide CNVs in tilapia. These CNVs among and within tilapia populations may have functional effects on phenotypes and specific adaptation to particular environments.

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

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Geisa Karine Kleemann

2009-01-01

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

Idade de maior sensibilidade de tilápias-do-nilo aos tratamentos de masculinização por banhos de imersão Most sensitivity age to masculinization of Nile tilapia by immersion baths

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Robie Allan Bombardelli

2007-02-01

Full Text Available Objetivou-se determinar o período ontogênico de maior sensibilidade de tilápias-do-nilo (Oreochromis niloticus aos tratamentos de masculinização com 17 a-metiltestosterona (MT, realizados via banhos de imersão com 2,0 mg MT.L-1 por um período de 36 horas. Nos tratamentos hormonais, foram utilizadas 3.000 tilápias distribuídas em 15 recipientes plásticos com capacidade para 2,0 L (unidades experimentais, em um delineamento experimental inteiramente casualizado, com cinco tratamentos e três repetições. Os tratamentos consistiram de um tratamento controle (tilápias de 16 DPE [dias pós-eclosão] submetidas à imersão sem hormônio e da imersão dos peixes em idades correspondentes a 16, 20, 24 e 28 DPE. Os parâmetros avaliados foram peso (PF e comprimento finais (CF, taxa de sobrevivência (S e proporção sexual. Os resultados de masculinização evidenciaram relação quadrática entre a idade e as taxas de masculinização, de modo que os melhores resultados foram obtidos aos 23,30 DPE (73,02% de machos. Os tratamentos não influenciaram as médias de PF, CF e S. A idade mais sensível aos tratamentos de masculinização via banhos de imersão para a linhagem de tilápia utilizada foi de 23,30 DPE.The present experiment was carried out to determine the different stages during ontogenesis of greater sensitivity to hormonal treatments of sex reversal of Nile tilapia larvae (Oreochromis niloticus with 17 a-metiltestosterone (MT by bath immersion in 2.0 mg of MT.L-1 for 36-h period. In the hormonal treatment, 3,000 Nile tilapia were allotted to 15 2 L- plastic containers (experimental units as a complete randomized design, with five treatments and three replicates. The treatments consisted of the fish immersion at different ages: control (fishes immersed at 16 DAH [days after hatching] and without hormone, and 16, 20, 24, and 28 DAH. Final weight (FW, final length (FL, survival rate (SR and sexual rate were the evaluated parameters

Tilapia Piscidin 4 (TP4 Stimulates Cell Proliferation and Wound Closure in MRSA-Infected Wounds in Mice

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Hang-Ning Huang

2015-05-01

Full Text Available Antimicrobial peptides (AMPs are endogenous antibiotics that directly affect microorganisms, and also have a variety of receptor-mediated functions. One such AMP, Tilapia piscidin 4 (TP4, was isolated from Nile tilapia (Oreochromis niloticus; TP4 has antibacterial effects and regulates the innate immune system. The aim of the present study was to characterize the role of TP4 in the regulation of wound closure in mice and proliferation of a keratinocyte cell line (HaCaT and fibroblast cell line (Hs-68. In vitro, TP4 stimulated cell proliferation and activated collagen I, collagen III, and keratinocyte growth factor (KGF gene expression in Hs-68 cells, which induces keratin production by HaCaT cells. This effect was detectable at TP4 concentrations of 6.25 µg/mL in both cell lines. In vivo, TP4 was found to be highly effective at combating peritonitis and wound infection caused by MRSA in mouse models, without inducing adverse behavioral effects or liver or kidney toxicity. Taken together, our results indicate that TP4 enhances the survival rate of mice infected with the bacterial pathogen MRSA through both antimicrobial and wound closure activities mediated by epidermal growth factor (EGF, transforming growth factor (TGF, and vascular endothelial growth factor (VEGF. The peptide is likely involved in antibacterial processes and regulation of tissue homeostasis in infected wounds in mice. Overall, these results suggest that TP4 may be suitable for development as a novel topical agent for wound dressing.

Safety and immunogenicity of an oral DNA vaccine encoding Sip of Streptococcus agalactiae from Nile tilapia Oreochromis niloticus delivered by live attenuated Salmonella typhimurium.

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Huang, L Y; Wang, K Y; Xiao, D; Chen, D F; Geng, Y; Wang, J; He, Y; Wang, E L; Huang, J L; Xiao, G Y

2014-05-01

Attenuated Salmonella typhimurium SL7207 was used as a carrier for a reconstructed DNA vaccine against Streptococcus agalactiae. A 1.02 kb DNA fragment, encoding for a portion of the surface immunogenic protein (Sip) of S. agalactiae was inserted into pVAX1. The recombinant plasmid pVAX1-sip was transfected in EPC cells to detect the transient expression by an indirect immunofluorescence assay, together with Western blot analysis. The pVAX1-sip was transformed by electroporation into SL7207. The stability of pVAX1-sip into Salmonella was over 90% after 50 generations with antibiotic selection in vitro while remained stable over 80% during 35 generations under antibiotic-free conditions. The LD50 of SL/pVAX1-sip was 1.7 × 10(11) CFU/fish by intragastric administration which indicated a quite low virulence. Tilapias were inoculated orally at 10(8) CFU/fish, the recombinant bacteria were found present in intestinal tract, spleens and livers and eventually eliminated from the tissues 4 weeks after immunization. Fish immunized at 10(7), 10(8) and 10(9) CFU/fish with different immunization times caused various levels of serum antibody and an effective protection against lethal challenge with the wild-type strain S. agalactiae. Integration studies showed that the pVAX1-sip did not integrate with tilapia chromosomes. The DNA vaccine SL/pVAX1-sip was proved to be safe and effective in protecting tilapias against S. agalactiae infection. Copyright © 2014 Elsevier Ltd. All rights reserved.

Culture Trials of Gymnarchus niloticus in Earthen and Concrete Ponds

African Journals Online (AJOL)

Culture trials of Gymnarchus niloticus in earthen and concrete pond was carried out. A total of 440 fingerlings of G. niloticus from Burutu River, Delta State, were collected. A total of 220 fingerlings were stocked in each of the receptacles. The fingerlings were fed with live artemia for two weeks and commercial feed of size ...

Marine Science

African Journals Online (AJOL)

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 ...

Observations on the helminth parasites of wild and cultured tilapia in ...

African Journals Online (AJOL)

A total of 449 specimen of Tilapia comprising Tilapia nilotica (Oreochromis), Tilapia zilli and Tilapia galilea (Sarotherodon) collected from the Federal and State Fish ponds, Okigwe and from the Imo River were examined for helminth infections. Out of these, only 5 (1.1%) fish were infected. These came from the wild. Tilapia ...

Incorporation du coprah et des cuticules de cacao et d'arachide ...

African Journals Online (AJOL)

Incorporation du coprah et des cuticules de cacao et d'arachide dans l'aliment du ( tilapia du nil( ( Oreohromis niloticus , linné, 1758) eleve en etang : Effet sur la croissance et la composition biochimique.

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

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.

Modeling growth of specific spoilage organisms in tilapia ...

African Journals Online (AJOL)

Tilapia is an important aquatic fish, but severe spoilage of tilapia is most likely related to the global aquaculture. The spoilage is mostly caused by specific spoilage organisms (SSO). Therefore, it is very important to use microbial models to predict the growth of SSO in tilapia. This study firstly verified Pseudomonas and Vibrio ...

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

Science.gov (United States)

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.

Acute hypoxia stress induced abundant differential expression genes and alternative splicing events in heart of tilapia.

Science.gov (United States)

Xia, Jun Hong; Li, Hong Lian; Li, Bi Jun; Gu, Xiao Hui; Lin, Hao Ran

2018-01-10

Hypoxia is one of the critical environmental stressors for fish in aquatic environments. Although accumulating evidences indicate that gene expression is regulated by hypoxia stress in fish, how genes undergoing differential gene expression and/or alternative splicing (AS) in response to hypoxia stress in heart are not well understood. Using RNA-seq, we surveyed and detected 289 differential expressed genes (DEG) and 103 genes that undergo differential usage of exons and splice junctions events (DUES) in heart of a hypoxia tolerant fish, Nile tilapia, Oreochromis niloticus following 12h hypoxic treatment. The spatio-temporal expression analysis validated the significant association of differential exon usages in two randomly selected DUES genes (fam162a and ndrg2) in 5 tissues (heart, liver, brain, gill and spleen) sampled at three time points (6h, 12h, and 24h) under acute hypoxia treatment. Functional analysis significantly associated the differential expressed genes with the categories related to energy conservation, protein synthesis and immune response. Different enrichment categories were found between the DEG and DUES dataset. The Isomerase activity, Oxidoreductase activity, Glycolysis and Oxidative stress process were significantly enriched for the DEG gene dataset, but the Structural constituent of ribosome and Structural molecule activity, Ribosomal protein and RNA binding protein were significantly enriched only for the DUES genes. Our comparative transcriptomic analysis reveals abundant stress responsive genes and their differential regulation function in the heart tissues of Nile tilapia under acute hypoxia stress. Our findings will facilitate future investigation on transcriptome complexity and AS regulation during hypoxia stress in fish. Copyright © 2017 Elsevier B.V. All rights reserved.

The Effects of Species Interaction and Pond Stocking Density on ...

African Journals Online (AJOL)

Burchell) and Heterobranchus bidorsalis (Geoffrey Saint-Hilaire) and pond stocking density on the culture of tilapia species which display different parental care strategies. In the presence of catfishes, the maternal mouth-brooder O. niloticus ...

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

Science.gov (United States)

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

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

Full Text Available Nile tilapia (Oreochromis niloticus, which is exotic to South America, is the most common species caught in artisanal fisheries at the Barra Bonita Reservoir, Southeastern Brazil. This species is of great socioeconomic importance for the region and keeps active a population of about 500 fishers. In the present study we assess reproduction, food dynamics and level of exploitation of O. niloticus, caught by artisanal fisheries in the Barra Bonita Reservoir. Specimens were collected monthly, from July 2004-June 2005, and a total of 1 715 specimens were analyzed. Each specimen was examined to obtain biological and biometric data: standard length (cm, total weight (g, reproductive data (sex and stage of maturation, and stomach contents (empty, partly full, and full. We also estimated the sex ratio (by macroscopic observation of gonads, reproductive period (by ovarian development and seasonal average of gonadosomatic index in females, and feeding habits (by stomach contents. The possible relationship between abiotic factors and the reproductive period was statistically verified using Spearman’s Rank Correlation. The FiSAT (ELEFAN I package was used to assess growth parameters, mortality rates and to infer exploitation rate from standard length frequencies. The O. niloticus population had a sex ratio of 1.3:1 (M:F. Results indicated that ripe females were captured throughout the year, with a higher frequency during the winter-2004 (with a frequency of 59%, at a mean temperature of 20.5°C, and in spring-2004 (with a frequency of 60.5% at a mean temperature of 21.18°C. The GSI mean values obtained by season were: winter-2004: 1.71; spring-2004: 1.72; summer-2005: 0.80, and autumn-2005: 1.19. The Spearman correlation indicated positive values with respect to pH, dissolved oxygen, electric conductivity, transparency and chlorophyll a, and negative values with respect to temperature, accumulated rainfall and altimetric benchmark. The main food items

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

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

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)

Bacterial ecology of tilapia fresh fillets and some factors that can influence their microbial quality Ecologia bacteriana de filés frescos de tilápia e de pontos capazes de influenciar a sua qualidade microbiológica

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Cleube Andrade Boari

2008-12-01

Full Text Available The purpose of research was to investigate the bacterial ecology of tilapia (Oreochromis niloticus fresh fillets and some factors that can influence its microbial quality. Samples of fish cultivation water (n = 20, tilapia tegument and gut (n = 20 and fresh fillets (n = 20 were collected in an experimental tilapia aquaculture located in the city of Lavras, Minas Gerais, Brazil. Staphylococcus spp., Aeromonas spp., Enterococcus spp. and Enterobacteriaceae were quantified using selective plating. For the enumeration of Pseudomonas spp., the most probable number technique (MPN was utilized. Bacterial colonies (n = 198 were identified by Gram strain and biochemical tests. Aeromonas spp., Pseudomonas spp., Enterococcus spp. and Enterobacteriaceae were found in the cultivation water (water from a fishpond cultivation, tegument, gut, and fresh fillets. Staphylococcus spp. was not isolated in the cultivation water. Salmonella spp. was not detected. The count variable of 10 to 10³ CFU or MPN.(g or mL-1. Associated to freshwater tilapia fillet processing, there is a large variety of microorganisms related to foodborne illnesses and fish products deterioration.A presente pesquisa foi conduzida com o objetivo de se investigar a ecologia microbiana de filés frescos de tilápia (Oreochromis niloticus e de pontos capazes de influenciar em sua qualidade microbiológica. Para sua condução, amostras de água de cultivo (n = 20, tegumento e trato gastrintestinal (n = 20 e filés frescos (n = 20 foram coletados em um sistema de produção aqüícola de água doce localizado em Lavras, Minas Gerais, Brasil. Staphylococcus spp., Aeromonas spp., Enterococcus spp., Enterobacteriaceae foram quantificados através de plaqueamento seletivo. Pseudomonas spp. foi enumerada através da técnica do número mais provável. Colônias (n = 198 foram identificadas por coloração de Gram e testes bioquímicos. Aeromonas spp., Pseudomonas spp., Enterococcus spp. e

Signatures of selection in tilapia revealed by whole genome resequencing.

Science.gov (United States)

Xia, Jun Hong; Bai, Zhiyi; Meng, Zining; Zhang, Yong; Wang, Le; Liu, Feng; Jing, Wu; Wan, Zi Yi; Li, Jiale; Lin, Haoran; Yue, Gen Hua

2015-09-16

Natural selection and selective breeding for genetic improvement have left detectable signatures within the genome of a species. Identification of selection signatures is important in evolutionary biology and for detecting genes that facilitate to accelerate genetic improvement. However, selection signatures, including artificial selection and natural selection, have only been identified at the whole genome level in several genetically improved fish species. Tilapia is one of the most important genetically improved fish species in the world. Using next-generation sequencing, we sequenced the genomes of 47 tilapia individuals. We identified a total of 1.43 million high-quality SNPs and found that the LD block sizes ranged from 10-100 kb in tilapia. We detected over a hundred putative selective sweep regions in each line of tilapia. Most selection signatures were located in non-coding regions of the tilapia genome. The Wnt signaling, gonadotropin-releasing hormone receptor and integrin signaling pathways were under positive selection in all improved tilapia lines. Our study provides a genome-wide map of genetic variation and selection footprints in tilapia, which could be important for genetic studies and accelerating genetic improvement of tilapia.

Desempenho da tilápia-do-Nilo arraçoada com dietas contendo farinha de sangue bovino atomizado ou convencional = Performance of nile tilapia fed with spray-dried or vat-dries bovine blood meal

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Willian Vicente Narváez-Solarte

2011-07-01

Full Text Available Foi avaliado o desempenho e os índices de rendimento da tilápia-do-Nilo (Oreochromis niloticus alimentada com níveis crescentes de farinha de sangue atomizado (FSA ou de farinha de sangue convencional (FSC em dietas formuladas com base em aminoácidos digestíveis. Foram utilizados 252 alevinos, distribuídos num delineamento inteiramente casualizado, em esquema fatorial (2 x 4 + 1, duas classes de farinha de sangue com quatro níveis de inclusão de cada farinha na dieta, e uma dieta-controle, com quatro repetições. Os tratamentos consistiram em uma dieta-controle à base de farelo de soja, contendo 34% de proteína digestível (PD e 3.200 kcal de energia digestível kg-1 (ED, mais quatro rações formuladas com FSA e quatro rações com FSC, com inclusões de 5, 10, 15 e 20% de cada farinha na ração, mantendo-se os níveis de PD, ED, fósforo, cálcio, lisina, metionina, treonina e triptofano idênticos aos da dieta-controle. Concluiu-se que é possível utilizar até 15% da FSC em rações para tilápia-do-Nilo na fase de 5 a 150 g de peso vivo.The study evaluated the performance and carcass composition index of Nile tilapia (Oreochromis niloticus fed with diets containing increasing levels of spray-dried blood meal (SDBM and vat-dried blood meal (VDBM and formulated based on digestible amino acids. Two hundred and fifty-two fingerlings were distributed in a completelyrandomized design, in a (2 x 4 + 1 factorial model, two types of blood meal with four levels of each blood meal in the diet, and a control diet (without blood meal, with four replications. The treatments consisted of soybean meal-based control diet, with 34%digestible protein (DP and 3,200 kcal of digestible energy kg-1 (DE, plus four diets formulated with SDBM and four diets with VDBM, containing 5, 10, 15 and 20% of each meal in feed, maintaining identical DP, DE, phosphorus, calcium, lysine, methionine, threonine and tryptophan levels as those of the control diet. The

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

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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

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African Journals Online (AJOL)

Items 101 - 150 of 544 ... ... The Nile Tilapia, Oreochromis Niloticus After Treatment With Heavy Metals ... Vol 13, No 1 (2011), Checklist of the aquatic macrophytes of Jebba Lake, ... Comparison of phytoremediation and filtration in remediation Of ...

Simultaneous stimulation of glycolysis and gluconeogenesis by feeding in the anterior intestine of the omnivorous GIFT tilapia, Oreochromis niloticus

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Yong-Jun Chen

2017-06-01

Full Text Available The present study was performed to investigate the roles of anterior intestine in the postprandial glucose homeostasis of the omnivorous Genetically Improved Farmed Tilapia (GIFT. Sub-adult fish (about 173 g were sampled at 0, 1, 3, 8 and 24 h post feeding (HPF after 36 h of food deprivation, and the time course of changes in intestinal glucose transport, glycolysis, glycogenesis and gluconeogenesis at the transcription and enzyme activity level, as well as plasma glucose contents, were analyzed. Compared with 0 HPF (fasting for 36 h, the mRNA levels of both ATP-dependent sodium/glucose cotransporter 1 and facilitated glucose transporter 2 increased during 1-3 HPF, decreased at 8 HPF and then leveled off. These results indicated that intestinal uptake of glucose and its transport across the intestine to blood mainly occurred during 1-3 HPF, which subsequently resulted in the increase of plasma glucose level at the same time. Intestinal glycolysis was stimulated during 1-3 HPF, while glucose storage as glycogen was induced during 3-8 HPF. Unexpectedly, intestinal gluconeogenesis (IGNG was also strongly induced during 1-3 HPF at the state of nutrient assimilation. The mRNA abundance and enzyme activities of glutamic-pyruvic and glutamic-oxaloacetic transaminases increased during 1-3 HPF, suggesting that the precursors of IGNG might originate from some amino acids. Taken together, it was concluded that the anterior intestine played an important role in the regulation of postprandial glucose homeostasis in omnivorous tilapia, as it represented significant glycolytic potential and glucose storage. It was interesting that postprandial IGNG was stimulated by feeding temporarily, and its biological significance remains to be elucidated in fish.

Bioavailability of heavy metals in fresh water Tilapia nilotica (Oreachromis niloticus Linnaeus, 1758): potential risk to fishermen and consumers.

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El-Sadaawy, Manal M; El-Said, Ghada F; Sallam, Neama A

2013-01-01

The study was undertaken to assess the accumulation of some heavy metals (Cr, Co, Cu, Ni, Zn, Pb and Cd) in different tissues (muscle, gills, heart, liver, brain, bone and skin) of Tilapia nilotica. It is one of the most edible fish species in Egypt and was collected from a commercial fish farm in order to evaluate their potential risk to fishermen and consumers. This fish farm is fed with discharged water containing agricultural, industrial, sewage and domestic wastes. The length-weight relation and condition factor calculation of Tilapia nilotica samples showed a significant linear regression (r(2) = 0.920) and an average condition factor of 4.1 g/cm(3). This indicated that the health status for the studied fish samples was good. Metal pollution index (MPI) values for the determined heavy metals in the different tissues reflected that the muscle was the only tissue that had the lowest content. Provisional Tolerable Weekly Intake (PTWI) values for the investigated heavy metals were lower than those reported for the permissible limits. The data were evaluated by using ANOVA statistical analysis. For appraising the human health risk effects of heavy metals in fish muscle, estimated dietary intake (EDI) and hazard quotient (HQ) were determined. HQ levels indicated that Cr and Co were the only heavy metals among the determined ones that had values more than unity. Also, their relative contributions in fish consumptions were Cr> Co> Pb> Ni> Cu> Cd> Zn. The highest average HQ value of chromium determined in this study referred to the possible adverse effects of Cr on human health. Accordingly, the potential public health risks from dietary exposure to hazardous contaminants in fish species from fish farms must be continually subjected to research, regulation and debate.

Simultaneous stimulation of glycolysis and gluconeogenesis by feeding in the anterior intestine of the omnivorous GIFT tilapia, Oreochromis niloticus.

Science.gov (United States)

Chen, Yong-Jun; Zhang, Ti-Yin; Chen, Hai-Yan; Lin, Shi-Mei; Luo, Li; Wang, De-Shou

2017-06-15

The present study was performed to investigate the roles of anterior intestine in the postprandial glucose homeostasis of the omnivorous Genetically Improved Farmed Tilapia (GIFT). Sub-adult fish (about 173 g) were sampled at 0, 1, 3, 8 and 24 h post feeding (HPF) after 36 h of food deprivation, and the time course of changes in intestinal glucose transport, glycolysis, glycogenesis and gluconeogenesis at the transcription and enzyme activity level, as well as plasma glucose contents, were analyzed. Compared with 0 HPF (fasting for 36 h), the mRNA levels of both ATP-dependent sodium/glucose cotransporter 1 and facilitated glucose transporter 2 increased during 1-3 HPF, decreased at 8 HPF and then leveled off. These results indicated that intestinal uptake of glucose and its transport across the intestine to blood mainly occurred during 1-3 HPF, which subsequently resulted in the increase of plasma glucose level at the same time. Intestinal glycolysis was stimulated during 1-3 HPF, while glucose storage as glycogen was induced during 3-8 HPF. Unexpectedly, intestinal gluconeogenesis (IGNG) was also strongly induced during 1-3 HPF at the state of nutrient assimilation. The mRNA abundance and enzyme activities of glutamic-pyruvic and glutamic-oxaloacetic transaminases increased during 1-3 HPF, suggesting that the precursors of IGNG might originate from some amino acids. Taken together, it was concluded that the anterior intestine played an important role in the regulation of postprandial glucose homeostasis in omnivorous tilapia, as it represented significant glycolytic potential and glucose storage. It was interesting that postprandial IGNG was stimulated by feeding temporarily, and its biological significance remains to be elucidated in fish. © 2017. Published by The Company of Biologists Ltd.

The sensory acceptability of a tilapia (Oreochromis niloticus mechanically separated meat-based spread Aceitabilidade de patê à base de carne de tilápia (Oreochromis niloticus mecanicamente separada

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Daniela De Grandi Castro Freitas

2012-06-01

Full Text Available Mechanically Separated Meat (MSM is an alternative for the diversification of new fish-based products and also as a solution for the use of waste from the filleting industries. Tilapia MSM was used in this study for the formulation of a fish spread aimed at investigating its acceptability by consumers. Two spread formulations were prepared with different types of commercial salt: seasoned salt (A and common salt (B. The consumers (112 evaluated their acceptance with respect to overall impression, spreadability, appearance and flavour acceptability on a 9-point hedonic scale. A microbiological analysis of the Tilapia MSM was also carried out and the chemical composition of the Tilapia MSM-based spread determined. When considering the acceptance of all the consumers, the overall impression, appearance and flavour were significantly (P A carne mecanicamente separada (CMS é uma alternativa para a diversificação de novos produtos à base de pescado e também se mostra como um destino para os resíduos da indústria de filetagem. A carne mecanicamente separada de tilápia foi utilizada, neste estudo, na formulação de patê, com o objetivo de investigar a aceitabilidade desse produto pelos consumidores. Duas formulações de patê foram preparadas, com diferentes tipos de sais comerciais: sal temperado (A e sal comum (B. Consumidores (112 avaliaram a aceitação em relação à impressão global, à espalhabilidade, à aparência e ao sabor em escala hedônica de nove pontos. A análise microbiológica da carne mecanicamente separada de tilápia e a composição química da formulação de patê de tilápia também foram determinadas. Quando a aceitação de todos os consumidores foi considerada, a impressão global, a aparência e o sabor foram significativamente (p < 0,05 inferiores para o patê de tilápia com sal comum (B. No entanto, três diferentes grupos de consumidores foram encontrados a partir da aceitabilidade da impressão global do

Effect of stocking densities on growth, production and survival rate of red tilapia in hapa at fish hatchery Chilya Thatta, Sindh, Pakistan

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Abdul Malik Daudpota

2014-12-01

Full Text Available Effect of stocking density on growth, production and survival of red tilapia (Oreochromis mossambicus × O. niloticus were conducted in hapa for 60 days at Chilya Thatta. Tilapia fry (4.5±0.02 cm, 2.0±0.01 g were stocked into hapa (4.5x2.4x1 m. Three treatments with two replicates were used: T1-200; T2-250 and T3-300 fry/hapa. Fry were fed twice a daily with pelleted feed containing 35% protein, 5% of total biomass. After 60 days, the highest growth were determined in T1 (49.8±0.0 g while in T3 lowest growth (29.09±0.0 g was recorded. Production (9.56, 10.13 and 8.12 kg/m3/60days in T1, T2 and T3 respectively were significantly different (P0.05. Survival was significantly different among treatments (P<0.01. Highest survival (100% was attained in T1 with lower stocking density, followed by T2 (98% and T3 (95%. Water quality parameters recorded throughout the study period were found within the ranges for fish culture such as temperature 27.2 to 28.5 °C, dissolved oxygen 5.8 to 6.4 mg/l, pH 6.9 to 7.6, ammonia from 0.45 to 0.51 mg/l, hardness 106 to 110 ppm and nitrite 0.151 to 0.162 mg/l.

Effect of stocking density on growth, maturity, fecundity, reproductive ...

African Journals Online (AJOL)

Jane

2011-08-29

Aug 29, 2011 ... niloticus into freshwater habitats of India took place in. 1952 and 1970 ..... Turbot (Psetta maxima) in the net cages on the southeastern Coast ... Asian Fish. ... ideal stocking density for cage culture of Monosex Nile Tilapia.

Mapping QTL for Omega-3 Content in Hybrid Saline Tilapia.

Science.gov (United States)

Lin, Grace; Wang, Le; Ngoh, Si Te; Ji, Lianghui; Orbán, Laszlo; Yue, Gen Hua

2018-02-01

Tilapia is one of most important foodfish species. The low omega-3 to omega-6 fatty acid ratio in freshwater tilapia meat is disadvantageous for human health. Increasing omega-3 content is an important task in breeding to increase the nutritional value of tilapia. However, conventional breeding to increase omega-3 content is difficult and slow. To accelerate the increase of omega-3 through marker-assisted selection (MAS), we conducted QTL mapping for fatty acid contents and profiles in a F 2 family of saline tilapia generated by crossing red tilapia and Mozambique tilapia. The total omega-3 content in F 2 hybrid tilapia was 2.5 ± 1.0 mg/g, higher than that (2.00 mg/g) in freshwater tilapia. Genotyping by sequencing (GBS) technology was used to discover and genotype SNP markers, and microsatellites were also genotyped. We constructed a linkage map with 784 markers (151 microsatellites and 633 SNPs). The linkage map was 2076.7 cM long and consisted of 22 linkage groups. Significant and suggestive QTL for total lipid content were mapped on six linkage groups (LG3, -4, -6, -8, -13, and -15) and explained 5.8-8.3% of the phenotypic variance. QTL for omega-3 fatty acids were located on four LGs (LG11, -18, -19, and -20) and explained 5.0 to 7.5% of the phenotypic variance. Our data suggest that the total lipid and omega-3 fatty acid content were determined by multiple genes in tilapia. The markers flanking the QTL for omega-3 fatty acids can be used in MAS to accelerate the genetic improvements of these traits in salt-tolerant tilapia.

The Business Analysis of Tilapia and Tilapia Mixed Common Carp Floating Cages at Toba Lake in Kelurahan Haranggaol Haranggaol Horison Sub District Simalungun Regency Notrh Sumatera Utara

OpenAIRE

Hutagalung, Ningsih Agresia; ', Hendrik; ', Darwis

2016-01-01

This study was conducted on 26 January to February 9 2016 in the Kelurahan Haranggaol Haranggaol Horison sub district Simalungun regency north sumatera province. The purpose of the study was to determine and profit tilapia and tilapia mixed common carp and tilapia floating cage tilapia and business, know tilapia mixed common carp in floating cage in the review of several criteria investation like FRR, RCR, PPC. The method used in this research is a case study. Based on the results obtained by...

Feeding habits and trace metal concentrations in the muscle of ...

African Journals Online (AJOL)

KBHEEMA

The proportions of different food items consumed varied during the dry and wet .... predominant ions in the lake water are sodium and bicarbonates and the lake is ... namely the Nile Tilapia (Orechromis niloticus L., 1758), the African catfish ...

Browse Title Index

African Journals Online (AJOL)

... tilapia (Oreochoromis niloticus) harvested from four lakes in the north of Cameroon .... BA Milton, VM Juan, MV Maria, A Alejandro, PCJ Jose ... Vol 7, No 14 (2008), Chemical composition and antibacterial activity of the essential oil of Pinus ...

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.

Body lipid deposition in Nile tilapia fed on rations containing tannin Deposição lipídica corporal em tilápia-do-nilo alimentada com rações com tanino

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Felipe Shindy Aiura

2007-01-01

Full Text Available The aim of this work was to evaluate the effect of tannin sources and levels in rations, on the productive performance and body lipid deposition of Nile tilapias (Oreochromis niloticus during the finishing phase. Three hundred and forty-two fishes were distributed in 18 tanks. Rations were prepared using corn, sorghum varieties, with low and high tannin content, and tannic acid at 0.08, 0.34, and 0.60%. Weight gain, apparent feed conversion and protein efficiency rate were not influenced by the treatments. The highest body lipid deposition was observed for the tannic acid treatment (14.39%, while the diet containing sorghum with high tannin content yielded leaner body (12.01% than that of sorghum with low tannin content (13.31%. Diets containing sorghum provided lower levels of visceral fat. Rations with tannin contents did not harm the productive performance of Nile tilapia.O objetivo deste trabalho foi avaliar o efeito de fontes e níveis de tanino em rações para tilápia-do-nilo (Oreochromis niloticus, durante a engorda, sobre o desempenho produtivo e deposição lipídica corporal. Foram utilizados 342 peixes, distribuídos em 18 tanques. As rações foram preparadas com milho, variedades de sorgo com baixo e alto teor de tanino, e com ácido tânico a 0,08, 0,34, e 0,60%. Ganho de peso, conversão alimentar aparente e taxa de eficiência protéica não foram influenciados pelos tratamentos. A maior deposição lipídica corporal foi observada nas dietas com ácido tânico (14,39%; a dieta de sorgo com alto teor de tanino resultou em carcaças mais magras (12,01% do que as de sorgo com baixo teor de tanino (13,31%. Dietas com sorgo proporcionaram menores teores de gordura visceral. A presença de tanino nas rações não prejudicou o desempenho produtivo da tilápia-do-nilo.

Environmental color affects Nile tilapia reproduction

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Volpato G.L.

2004-01-01

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

effort de pêche et production piscicole au lac d'ayame i

African Journals Online (AJOL)

USER

-made Lake Ayamé I, from. August 2004 to July ... by the reappearance of tilapia, Oreochromis niloticus, reported as scarce from 1991 to 1996 in the landing, and the abundance .... d'aucune structure d'enregistrement des captures. Il accueille ...

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.

[Influences of ration level and initial body weight on growth and size hierarchy of hybrid tilapia, Oreochromis mossambicus x O. niloticus].

Science.gov (United States)

Wang, Yan

2003-02-01

72 hybrid tilapia were distributed into twelve tanks, each stocked in six fish (A, B, C, D, E, F) with different body size. The initial body weight was 62.69 +/- 1.46 g for fish A, 56.48 +/- 1.30 g for B, 50.75 +/- 1.19 g for C, 35.56 +/- 1.18 g for D, 31.05 +/- 0.88 g for E, and 27.35 +/- 0.95 g for F (mean +/- SE). The fish were reared under four ration levels (deprived of feed, fed at 1.5% body weight per day (BW.d-1), fed at 3.0% BW.d-1, or fed excess) throughout four weeks, respectively. The specific growth rate (SGR) and feed efficiency (FE) of the fish increased with increasing ration level up to 3.0% BW.d-1, and then, SGR maintained at a constant level while FE dropped with continuing increase of ration. The variance coefficient of SGR and final body weight was relatively high in the fish that fed at 1.5% BW.d-1. For fish A, SGR was not significantly different, between 1.5% BW.d-1, 3.0% BW.d-1 and fed excess, while in fish F, relatively high variations were found among different ration treatments. This experiment revealed that the growth and size hierarchy of hybrid tilapia were related to their ration level and initial body size. Under ration levels more than 3.0% BW.d-1, SGR was usually high, and size hierarchy was relatively weak.

A metabolomic investigation into the effects of temperature on Streptococcus agalactiae from Nile tilapia (Oreochromis niloticus) based on UPLC-MS/MS.

Science.gov (United States)

Hu, Wen-Ting; Guo, Wei-Liang; Meng, Ai-Yun; Sun, Yun; Wang, Shi-Feng; Xie, Zhen-Yu; Zhou, Yong-Can; He, Chaozu

2017-10-01

Streptococcosis caused by Streptococcus agalactiae is one of the most serious diseases in farmed tilapia, and temperature is one of the most important environmental factors related to its outbreak. To elucidate the influence of temperature variation on the pathogen from a metabolic perspective, the global metabolomics of 2 pathogenic strains of S. agalactiae from sick tilapia were analyzed at 35°C and 25°C using ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) combined with pattern recognition approaches and pathway analysis. The result showed that the metabolic status of S. agalactiae was extensively affected by its culture temperature. Based on the results of metabolites contributing to these differences, a large number of nucleotides and their ramifications were markedly elevated at 35°C. Various energy substances, components of the cell wall and substances associated with stress regulation such as glyceraldehyde 3-phosphate, pyroglutamic acid, glutamate, d-Alanyl-d-alanine, glycerophosphocholine, dephospho-CoA, and oxidized glutathione increased when the strains were cultured at 35°C. Additionally, a general decrease in various precursors of capsule, antigen, and virulence protein formation were detected including mannose, maltotriose, N-acetyl-d-glucosamine 6-phosphate, uracil, proline, and citrulline. These metabolic changes indicated that metabolic activity decreased, while adaptive ability to environment and pathogenicity to host increased at high temperature. This study is the first to determine the metabolomic responses of S. agalactiae to temperature, and the results are useful to reveal its pathogenic mechanism and find effective disease control. Copyright © 2017 Elsevier B.V. All rights reserved.

Suplementação de vitamina C em rações para reversão sexual da tilápia do Nilo Vitamin C diet supplementation for sex reversal of the Nile tilapia

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Glaucio Nogueira Toyama

2000-06-01

Full Text Available O estudo avaliou o efeito da suplementação de vitamina C: 0; 50; 100; 200; 400; 600; 800; 1000 mg kg-1 na dieta de reversão sexual da tilápia do Nilo (Oreochromis niloticus. Foram avaliados o ganho de peso e incremento em comprimento aos 0, 10, 20 e 30 dias de tratamento; porcentagem da sobrevivência final (S% e porcentagem de reversão sexual (RS% de pós-larvas estocadas em "hapas" de 0,08 m³. A partir do 20º dia, foram observadas diferenças (PThe effects of vitamin C supplementation (0; 50; 100; 200; 400; 600; 800; 1,000 mg kg-1 of diet on diets for sex reversal of the Nile tilapia, Oreochromis niloticus, were evaluated on groups of 600 larvae stocked in 0.08 m³ hapas and fed for 30 days with hormone-treated feeds containing different supplementation levels (n=3. Weight gain and total length increment were evaluated after days 0, 10, 20 and 30. Survival rate (S% and sex reversal rate (SR% were determined at the end of the experimental period. Weight gain and total length became significantly different only after day 20 (P<0.0001. Best results for weight gain were attained with dietary vitamin C levels above 800 mg kg-1, while the best results for growth in length were attained with dietary vitamin C levels above 400 mg kg-1. Levels of supplementation higher than 200 mg kg-1 did not lead to better survival rates. SR% values were not significantly affected by vitamin C supplementation of sex reversal diets (P<0.9993. Optimal values for vitamin C supplementation of sex reversal diets for the Nile tilapia, derived from polinomial regression analysis procedures, were: weight gain 859.5 mg; growth in length 765.0 mg, and for survival rate 685.7 mg.

Radiation decontamination and disinfestation of salted dried tilapia fish (Koobi)

International Nuclear Information System (INIS)

Nketsia-Tabiri, J.

2004-01-01

Salted dried tilapia (Oreochromis niloticus) fish locally called koobi was investigated with the view of establishing the effective radiation dose for controlling microbial and insect activity on the product. Total viable count (TVC) of market samples of koobi ranged between log 10 4.11 - 6.78 cfu/g, whilst mould and yeast count ranged between log 10 1.38-3.38 cfu/g. Staphylococcus aureus counts ranged between log 10 2.85 - 4.15 cfu/g. After 4 weeks storage under ambient conditions, total viable count increased to log 10 7.5 ± 2.5 cfu/g. Significant reduction in total viable count was observed after treatment with gamma radiation. A least square regression fitted through the data points indicated that 1.3 kGy would be required to reduce the microbial population on the product by one log cycle. Insects and pink colonies of halophilic bacteria were observed on all the nonirradiated samples after 4 weeks storage. Treatment with 3 kGy gamma radiation eliminated all insect forms, while microbial population was controlled with TVC ranging between log 10 1.9 ± 1.1 and log 10 10 2.7 ± 1.6 cfu/g throughout the 16 weeks storage period. The proliferation of halophilic bacteria and subsequent appearance of pink colonies on irradiated koobi was suppressed until the 16th week. Irradiation, therefore, extended the shelf-life of koobi from 4 to 15 weeks. (au)

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

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.

Dynamic modeling of the INAPRO aquaponic system

NARCIS (Netherlands)

Karimanzira, Divas; Keesman, Karel J.; Kloas, Werner; Baganz, Daniela; Rauschenbach, Thomas

2016-01-01

The use of modeling techniques to analyze aquaponics systems is demonstrated with an example of dynamic modeling for the production of Nile tilapia (Oreochromis niloticus) and tomatoes (Solanum lycopersicon) using the innovative double recirculating aquaponic system ASTAF-PRO. For the management

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

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M. S. G. Moura e Silva

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

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.; Severo, M.I.; Grenier-Loustalot, M.F.; Cabaleiro, H.L.; Almeida, M.R.M.G.

2005-01-01

) detector 'Canberra', coupled to a 4096 high pulse analyser. The 'Canberra' Gennie 2000 software was used to analyse the spectra. The isotopes nuclear characteristics in INAA, half-time, type of emission and gamma ray energies are well known and the 'ko parametric neutron activation analysis' (k0PNA) was a complementary method used to determine multi-elements in a given sample. The fish Nile tilapia, Oreochrormis niloticus, tissues samples analysed were: intestine; spleen; heart; testicle; kidney; liver; gills and muscle, The results obtained for the fish tissues sampling demonstrate 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.

Neuropeptide B in Nile tilapia Oreochromis niloticus: molecular cloning and its effects on the regulation of food intake and mRNA expression of growth hormone and prolactin.

Science.gov (United States)

Yang, Lu; Sun, Caiyun; Li, Wensheng

2014-05-01

Neuropeptide B (NPB) regulates food intake, energy homeostasis and hormone secretion in mammals via two G-protein coupled receptors, termed as GPR 7 and GPR 8. However, there is no study that reports the function of NPB in teleosts. In this study, the full-length cDNA of prepro-NPB with the size of 663bp was cloned from the hypothalamus of Nile tilapia. The CDS of the prepro-NPB is 387bp which encodes a precursor protein with the size of 128a.a. This precursor contains a mature peptide with the size of 29a.a, and it was named as NPB29. Tissue distribution study showed that this gene was mainly expressed in different parts of brain, especially in the diencephalon as well as hypothalamus, and the spinal cord in Nile tilapia. Fasting significantly stimulated the mRNA expression of NPB in the brain area without hypothalamus, and refeeding after fasting for 3 and 14days also showed similar effects on NPB expression. While, only short-term fasting (3days) and refeeding after fasting for 7 and 14days induced mRNA expression of NPB in the hypothalamus. Intraperitoneal (i.p.) injection of NPB remarkably elevated the mRNA expression of hypothalamic neuropeptide Y (NPY), cholecystokinin 1 (CCK1) and pituitary prolactin (PRL), whereas significantly inhibited growth hormone (GH) expression in pituitary. These observations in the present study suggested that NPB may participate in the regulation of feeding and gene expression of pituitary GH and PRL in Nile tilapia. Copyright © 2014 Elsevier Inc. All rights reserved.

Do sex reversal procedures differentially affect agonistic behaviors and sex steroid levels depending on the sexual genotype in Nile tilapia?

Science.gov (United States)

Gennotte, Vincent; Akonkwa, Balagizi; Mélard, Charles; Denoël, Mathieu; Cornil, Charlotte A; Rougeot, Carole

2017-04-01

In Nile tilapia Oreochromis niloticus, phenotypic males and females with different sexual genotypes (XX, XY, YY) have particular behavioral and physiological traits. Compared to natural XX females and XY males, XY and YY females and XX males expressed higher level of aggressiveness that could be related to higher levels of 17β-estradiol and 11-ketotestosterone, respectively. Our results suggest that the presence of a Y chromosome increases aggressiveness in females. However, since the same relationship between aggressiveness and the Y chromosome is not observed in males, we can hypothesize that the differences in aggressiveness are not directly dependent on the genotype but on the sex reversal procedures applied on young fry during their sexual differentiation to produce these breeders. These hormonal treatments could have permanently modified the development of the brain and consequently influenced the behavior of adults independently of their genotype. In both hypotheses (genotype or sex reversal influence), the causes of behavioral modifications have to be searched in an early modification of the brain sexual differentiation. © 2017 Wiley Periodicals, Inc.

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

DEFF Research Database (Denmark)

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

2013-01-01

Guangdong province is the most important region for tilapia culture in China. However, it is also an endemic region for fishborne zoonotic trematodes (FZT), which pose a risk to human food safety and health. A study was designed to assess the status of trematode parasite infections in tilapia...... aquaculture systems as an indicator of potential risks from FZT associated with consumption of tilapia. Tilapia from nursery and grow-out ponds were sampled from monoculture, polyculture and integrated aquaculture systems. The results from 388 tilapia examined revealed a very low prevalence (1...... for tilapia are generally effective in preventing transmission of these parasites into tilapia production systems, the improvement of pond management practices and biosecurity must be maintained at a high level....

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

Science.gov (United States)

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

2017-05-11

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

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

Directory of Open Access Journals (Sweden)

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

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), ...

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ACSS

Health management issues are not well understood by fish farmers, with ... concerns for risks of trans-boundary ... a challenge to hatchery operators, causing ... Farmer's perception on diseases .... contribute to food security and income ... Small- scale aquaculture farms growing Nile tilapia (O. niloticus) and/or ornamentals.

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

Developing a machine vision system for simultaneous prediction of freshness indicators based on tilapia (Oreochromis niloticus) pupil and gill color during storage at 4°C.

Science.gov (United States)

Shi, Ce; Qian, Jianping; Han, Shuai; Fan, Beilei; Yang, Xinting; Wu, Xiaoming

2018-03-15

The study assessed the feasibility of developing a machine vision system based on pupil and gill color changes in tilapia for simultaneous prediction of total volatile basic nitrogen (TVB-N), thiobarbituric acid (TBA) and total viable counts (TVC) during storage at 4°C. The pupils and gills were chosen and color space conversion among RGB, HSI and L ∗ a ∗ b ∗ color spaces was performed automatically by an image processing algorithm. Multiple regression models were established by correlating pupil and gill color parameters with TVB-N, TVC and TBA (R 2 =0.989-0.999). However, assessment of freshness based on gill color is destructive and time-consuming because gill cover must be removed before images are captured. Finally, visualization maps of spoilage based on pupil color were achieved using image algorithms. The results show that assessment of tilapia pupil color parameters using machine vision can be used as a low-cost, on-line method for predicting freshness during 4°C storage. Copyright © 2017 Elsevier Ltd. All rights reserved.