Showing papers on "Nile tilapia published in 2018"
TL;DR: Outbreaks of TiLV disease in farmed tilapia in two states, West Bengal and Kerala from India are reported, adding to the reports ofTiLV outbreaks in five countries across three continents.
155 citations
TL;DR: The data revealed that JCM1136 and JCM5805, as a feed additive at 108 CFU/g feed, could improve intestinal morphology, enhance immune status and disease resistance, and affect the gut microbiota of tilapia; thus, these additives could be used as probiotics for juvenile Nile Tilapia.
130 citations
TL;DR: Dietary administration of host-associated probiotics remarkably improved the growth performance, specific growth rate, weight gain, final weight, and feed conversion ratio of Nile tilapia.
128 citations
TL;DR: The fish nutrition and health solutions, Alfarouk towers, Zohdy Square, Kafrelsheikh, Egypt, and the Institute of Aquaculture, University of Stirlingshire, Stirling, United Kingdom, FK9 4LA are described.
Abstract: Mabrouk Elsabagh, Radi Mohamed, Eman M. Moustafa, Ahmad Hamza, Foad Farrag, 5 Olivier Decamp, Mahmoud A.O. Dawood, Mahmoud Eltholth 9 6 7 Department of Nutrition and Clinical Nutrition, Faculty of Veterinary Medicine, Kafrelsheikh 8 University, Kafrelsheikh, Egypt 9 Department of Aquaculture, Faculty of Aquatic and Fisheries Sciences, Kafrelsheikh 10 University, Kafrelsheikh, Egypt 11 3 Department of Fish Diseases and Management, Faculty of Veterinary Medicine, Kafrelsheikh 12 University, Kafrelsheikh, Egypt 13 AQUAVET for fish nutrition and health solutions, Alfarouk towers, Zohdy Square, 14 Kafrelsheikh, Egypt 15 5 Department of Anatomy and Embryology, Faculty of Veterinary Medicine, Kafrelsheikh 16 University, Kafrelsheikh, Egypt 17 6 INVE Asia Services 471 Bond St., Tambon Bangpood, Amphur Pakkred, Nonthaburi 11120, 18 Thailand 19 Department of Animal Production, Faculty of Agriculture, Kafrelsheikh University, 20 Kafrelsheikh, Egypt 21 Department of Hygiene and Preventive Medicine, Faculty of Veterinary Medicine, 22 Kafrelsheikh University, Kafrelsheikh, Egypt 23 9 Institute of Aquaculture, University of Stirling, Stirling, United Kingdom, FK9 4LA 24 25
124 citations
TL;DR: A 32-day experiment was conducted to evaluate the effects on the performance, feed utilization efficiency and body composition of a strategic inclusion of Black Soldier Fly larvae meal (MM) in a commercially formulated diet for advance nursing Nile tilapia.
Abstract: A 32-day experiment was conducted to evaluate the effects on the performance, feed utilization efficiency and body composition of a strategic inclusion of Black Soldier Fly larvae meal (MM) in a commercially formulated diet for advance nursing Nile tilapia (Oreochromis niloticus) Four isonitrogenous and isoenergetic diets were commercially formulated and manufactured as a control and three test diets with strategic inclusions of MM inclusions (0, 30, 50 and 80 g/kg) and poultry by-product meal substituting gradually three conventional expensive feedstuffs: fish meal, fish oil and soybean meal Fish (57 ± 05 g/fish) were nursed in a cage-in-lake system (Volta Lake, Ghana), under conditions similar to commercial farming practices Control and experimental diets were fed to triplicate cages by hand to visual satiety, six times per day Growth performance (final weight; weight gain and SGR), feed utilization efficiency indices (FCR and PER) and feed intake were not significantly different (p ≥ 05) between treatments Survival was significantly different (p < 05) but more likely explained by the stress related to frequent handling on the smaller fish Fish whole body composition (dry matter, crude protein, lipid, ash and fibre) was unaffected by the treatment (p ≥ 05), except for the fatty acid compositions which mirrored that of the diets
118 citations
TL;DR: Ten gkg−1 of probiotic BS application results in significantly higher survival of tilapia against Streptococcus agalactiae and can be considered to improve growth and immunological status intilapia farming.
115 citations
TL;DR: It is evoked that dietary CNP enhanced the performance, antioxidant and digestive enzymes activity, and innate immunity of Nile tilapia and its optimum level is 3.0g CNP/kg diet.
96 citations
TL;DR: The aquaculture production and health mangement practices of farmed fish in Kenya is described in order to document actions required for effective monitoring and regulation of future fish health problems across the country.
80 citations
TL;DR: This is the first study to establish the occurrence of several bacteria species infecting fish; and to determine antibiotic susceptibility of fish bacteria in Uganda, suggesting minimal levels of acquired antibiotic resistance in fish bacteria from the study area.
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 establish the occurrence of several bacteria species infecting fish; and to determine antibiotic susceptibility of fish bacteria in Uganda. The current study provides baseline information for future reference and fish disease management in the country.
80 citations
TL;DR: Results indicated that survival was higher in all dietary treatments as compared to the control fed fish, and mixture of these substances are promising as immune enhancher in aquacultured fish.
Abstract: The study investigated effect of dietary supplementation with malic acid, Bacillus subtilis and a mixture of the two (3 × 2 factorial trial) on Nile tilapia (Oreochromis niloticus) health. Treatment groups (T1–T6) were fed diets containing three levels of malic acid (0.0, 5.0 and 10.0 g/kg), each of which was supplemented with 0 and 1.1 × 105 cfu/g B. subtilis, respectively. Each treatment group was assigned randomly to triplicate groups of 35 fish (5.26 ± 0.06 g) in 18 tanks for 84 days. The results indicated that survival was higher in all dietary treatments as compared to the control fed fish. The highest values of FBW, WG and SGR (%), PER, PPV and ER were recorded in groups T4 and T6, which were fed diets supplemented with 5 g malic acid/kg and 1.1 × 105 cfu/g B. subtilis and 10 g malic acid/kg and 1.1 × 105 cfu/g B. subtilis, respectively. The best value of FCR was obtained in groups T4 and T6. The lowest total bacterial count in the gut and faeces was detected in fish from group T6. The values of haematocrit, haemoglobin, red blood cells, white blood cells, total protein, albumin and globulin were significantly higher (p < .05) in fish from groups T4 and T6 (diets supplemented with malic acid and B. subtilis). As compared to the control fed fish, te mixture of these substances are promising as immune enhancher in aquacultured fish.
77 citations
TL;DR: In conclusion, inclusion of 10 g kg −1 CDXOS derived from corncob improved growth performance and health status of Nile tilapia fingerlings.
TL;DR: Findings were based on nucleic acid detection by PCR, and future studies should seek to isolate the virus from fish in Lake Victoria and show its ability to cause disease and virulence in susceptible fish.
Abstract: Tilapia lake virus disease (TiLVD) has emerged to be an important viral disease of farmed Nile tilapia (Oreochromis niloticus) having the potential to impede expansion of aquaculture production. There is a need for rapid diagnostic tools to identify infected fish to limit the spread in individual farms. We report the first detection of TiLV infection by PCR in farmed and wild Nile tilapia from Lake Victoria. There was no difference in prevalence between farmed and wild fish samples (p = .65), and of the 442 samples examined from 191 fish, 28 were positive for TiLV by PCR. In terms of tissue distribution, the head kidney (7.69%, N = 65) and spleen (10.99%, N = 191), samples had the highest prevalence (p < .0028) followed by heart samples (3.45%, N = 29). Conversely, the prevalence was low in the liver (0.71%, N = 140) and absent in brain samples (0.0%, N = 17), which have previously been shown to be target organs during acute infections. Phylogenetic analysis showed homology between our sequences and those from recent outbreaks in Israel and Thailand. Given that these findings were based on nucleic acid detection by PCR, future studies should seek to isolate the virus from fish in Lake Victoria and show its ability to cause disease and virulence in susceptible fish.
26 Jul 2018
TL;DR: Findings obtained suggest that spermatogonial germ cells can be successfully transplanted directly into the testis of this teleost, for the first time in fish.
Abstract: Spermatogonial transplantation, developed in the past decade by Brinster and colleagues, is a fascinating and powerful technique utilized to investigate male reproductive biology, mainly the aspects related to spermatogenesis and the stem cell biology. This technique also offers tremendous potential for studies involving biotechnology, transgenic animals, and the preservation of the genetic stock of valuable animals or endangered species. Although germ cell transplantation is well characterized for mammals, there is no study utilizing this approach for fish. Due to its fast growth, relative small size when it reaches sexual maturity, good adaptability to different environmental conditions and economical importance, the tilapia (Oreochromis niloticus) is an excellent experimental model. In the present study, we investigated the viability of adult tilapias as a recipient model for germ cells transplantation in fish. For this purpose, all approaches utilized in the present study for spermatogonial transplantation, such as endogenous spermatogenesis depletion, obtention, selection and spermatonia labeling, and the transplantation through the common urogenital papilla, were standardized in our laboratory. The preliminary results found for the recipient tilapia testes, evaluated by light and fluorescence microscopy, showed the presence of PKH26 labeled germ cells cysts in the seminiferous tubules. These findings obtained, for the first time in fish, suggest that spermatogonial germ cells can be successfully transplanted directly into the testis of this teleost. Therefore, tilapias might be utilized as an experimental model to investigate the germ cell biology and the testis function in teleosts. Moreover, this technique could be also utilized as a potential approach for fish bioengineering, preservation of genetic stock of endangered fish species or fish strains carrying commercially valuable traits.
TL;DR: N. oculata co-product, when replacing 33% of fishmeal in tilapia feed, led to fish performance and flesh composition comparable to that of fish fed the reference diet, but its nutrient digestibility needs to be improved to achieve higher replacement levels.
Abstract: Microalgae companies increasingly seek markets for defatted biomass that is left over after extracting omega-3 rich oil for human nutraceuticals and crude oil for fuels. Such a protein-rich co-product is a promising alternative to unsustainably sourced fishmeal in aquaculture diets. We report the first evaluation of co-product of the marine microalga Nannochloropsis oculata (N. oculata co-product) for replacing fishmeal in diets of Nile tilapia, a globally important aquaculture species. We conducted a nutrient digestibility experiment with N. oculata dried whole cells and N. oculata co-product, followed by an 84-day nutritional feeding experiment with N. oculata co-product. N. oculata co-product, more nutrient-dense than whole cells, had the highest digestibility for lysine, an essential amino acid that is often deficient in terrestrial crop meals; and for 20:5 n-3 EPA, making it a good option for EPA supplementation in tilapia feed. N. oculata co-product, despite containing higher amounts of protein than whole cells, had significantly lower digestibility for crude protein than whole cells. Apparent digestibility coefficients (ADC) of methionine were significantly lower in N. oculata co-product than in whole cells. The nutritional feeding experiment compared diets with N. oculata co-product that replaced fishmeal as follows: 0% replacement in reference diet (fishmeal as 7% of total diet) and test diets with 33%, 66% and 100% replacement of fishmeal (3%, 5.5%, and 8% of total diet, respectively). Results showed the 33% replacement diet yielded fish growth, feed conversion, and survival similar to the reference diet. Reduced digestibility and growth at greater N. oculata co-product inclusion levels may have been due to higher levels of anti-nutrients in co-product than whole cells. All diets yielded a n3:n6 ratio of tilapia fillet that is favorable for human consumption. Depositions of macro minerals and several trace elements in the fillet were not significantly different across diets. Thus, N. oculata co-product, when replacing 33% of fishmeal in tilapia feed, led to fish performance and flesh composition comparable to that of fish fed the reference diet, but its nutrient digestibility needs to be improved to achieve higher replacement levels.
TL;DR: Tilapia fed diet YFSFM-75 or BFS FM-75 recorded the lowest level of cholesterol, triglycerides high-density lipoprotein (HDL-C) and the highest value of serum phosphorus and calcium content was detected in the control diet and the lowest one was recorded in YFSfm-75 and BFSFM -75.
TL;DR: It is concluded that 1% Spirulina supplementation significantly improved immunity of Nile tilapia against Pseudomonas fluorescence than 2% SpirULina supplementation.
TL;DR: The potential roles of these B. subtilis probiotic candidates to stimulate immune responses both locally and systemically in tilapia are suggested, given that Bacillus bacteria were observed to populate the intestines of the dietary treatment groups.
TL;DR: The data suggest that the incorporation of a certain level dietary carbohydrates can benefit Nile Tilapia, and show that the well-known differences in the capacity of carnivorous and omnivorous fish species to use dietary carbohydrates could be linked to differences inThe regulation of the gluconeogenic and lipogenic pathways.
TL;DR: Vitamins C and E have the ability to ameliorate ZnONP oxidative stress toxicity in Nile tilapia and significantlyAmeliorated the toxic effects of ZnonPs.
Abstract: The effects of zinc oxide nanoparticles (ZnONPs) on antioxidants in Nile tilapia muscles and the protective role of vitamins C and E were examined. Two hundred males of Nile tilapia were held in aquaria (10 fishes/aquarium). Fishes were divided into 5 groups: 40 fishes in each group; the first group was the control; the 2nd and 3rd groups were exposed to 1 and 2 mg/L of ZnONPs, respectively; and the 4th and 5th group were exposed to 1 and 2 mg/L of ZnONPs and treated with a (500 mg/kg diet) mixture of vitamin C and E mixture (250 mg/kg diet of each). Muscles were collected on the 7th and 15th day of treatments. Muscle malondialdehyde, reduced glutathione levels, superoxide dismutase (SOD), catalase (CAT), reduced glutathione (GR), glutathione peroxidase (GPx), and glutathione-S-transferase (GST) activities were measured after treatments. Relative quantification of SOD, CAT, GR, GPx, and GST mRNA transcripts was detected in the muscles. Results showed that MDA and GSH concentration; SOD, CAT, GR, GPx, and GST activities; and mRNA expression were significantly decreased in groups exposed to ZnONPs. Vitamins C and E significantly ameliorated the toxic effects of ZnONPs. In conclusion, vitamins C and E have the ability to ameliorate ZnONP oxidative stress toxicity in Nile tilapia.
TL;DR: The present study indicated that OnTF might be involved in host defense against bacterial infection in Nile tilapia, and was significantly up‐regulated following challenges with Streptococcus galactiae and Aeromonas hydrophila in vivo.
TL;DR: The identified IL‐6 gene was identified in Nile tilapia and expression was significantly up‐regulated following challenges with Streptococcus agalactiae and LPS (in vivo and in vitro).
Abstract: Interleukin 6 (IL-6), a pleiotropic cytokine, plays an important role in humoral immune response, not only inducing the differentiation of B cells into plasma cells, but also promoting antibody-secreting cells (ASCs) to produce antibodies. In this study, Nile tilapia (Oreochromis niloticus) IL-6 (OnIL-6) was identified and characterized at expression level in response to bacterial infection and promotion of antibody production. The open reading frame of OnIL-6 ORF is consisted of 663 bp encoding a polypeptide of 220 amino acids. The deduced OnIL-6 protein contained an IL-6/G-CSF family signature, two conserved cysteine, and four α-helix bundles, which was highly homologous to other species. Spatial mRNA expression analysis revealed that the highest expression of OnIL-6 was observed in the thymus. After in vivo challenges of lipopolysaccharide (LPS) and Streptococcus agalactia (S. agalactiae), OnIL-6 expressions were significantly up-regulated in head kidney and spleen. The similar up-regulation of OnIL-6 was observed in the head kidney and spleen leukocytes in vitro stimulation with LPS and S. agalactiae. In addition, inducement with the recombinant OnIL-6 ((r)OnIL-6) in vitro caused significant increases in expressions of both sIgM and mIgM. Moreover, the (r)OnIL-6 stimulation enhanced the secretion of sIgM (more especially in P50 plasma-like B cells) and the production of mIgM in P60 and P70 B cell subsets (resting B cells, activated B cells and plasmablast-like B cells) in vitro. Taken together, this study indicated that OnIL-6 might be involved in host defense against bacterial infection and promote the production of antibody in Nile tilapia.
TL;DR: It is confirmed that dietary limonene can enhance the growth of Nile tilapia juveniles through the activation of key genes involved in somatotropic axis-mediated growth, nutrient digestion and antioxidant enzyme defence.
TL;DR: Both xylanase and phytase showed to be an effective tool to improve the nutrient availability and growth in Nile tilapia.
TL;DR: The study confirmed that Nile tilapia can use high level of carbohydrates without any deregulation of glucose homeostasis and suggested that these metabolic pathways at a molecular level are not the main actors explaining the efficient use of glucose intilapia.
TL;DR: The results suggested that microencapsulated oil might enhance immune activities in the Nile tilapia fed with HFD by improving intestinal structure and microflora.
TL;DR: Dietary yeast nucleotide administration at 0.25% improved blood proteins, leukocytes, antioxidant activity, non‐specific immunity, cytokine gene expression, and disease resistance of Nile Tilapia.
TL;DR: The findings suggest that W. sominefera root powder may have protective and immunotherapeutic roles in Nile tilapia against A. hydrophila infection which may be useful in controlling important fish bacterial diseases.
TL;DR: Dietary supplementation with cinnamaldehyde or thymol significantly reduced the malondialdehyde formation and increased glutathione reductase in the muscle, and increased lysozyme activity, IgM, IgG levels and catalase activity in the serum thus improved the antioxidant protective capacities and the immune status of the fish.