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Debnath PP, Dinh‐Hung N, Taengphu S, Nguyen VV, Delamare‐Deboutteville J, Senapin S, Vishnumurthy Mohan C, Dong HT, Rodkhum C. Tilapia Lake Virus was not detected in non-tilapine species within tilapia polyculture systems of Bangladesh. J Fish Dis 2022; 45:77-87. [PMID: 34580880 PMCID: PMC9293328 DOI: 10.1111/jfd.13537] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/04/2021] [Revised: 09/13/2021] [Accepted: 09/15/2021] [Indexed: 06/13/2023]
Abstract
Sixteen countries, including Bangladesh, have reported the presence of tilapia lake virus (TiLV), an emerging tilapia pathogen. Fish polyculture is a common farming practice in Bangladesh. Some unusual mortalities reported in species co-cultivated with TiLV-infected tilapia led us to investigate whether any of the co-cultivated species would also test positive for TiLV and whether they were susceptible to TiLV infection under controlled laboratory experiments. Using 183 samples obtained from 15 farms in six districts across Bangladesh, we determined that 20% of the farms tested positive for TiLV in tilapia, while 15 co-cultivated fish species and seven other invertebrates (e.g. insects and crustaceans) considered potential carriers all tested negative. Of the six representative fish species experimentally infected with TiLV, only Nile tilapia showed the typical clinical signs of the disease, with 70% mortality within 12 days. By contrast, four carp species and one catfish species challenged with TiLV showed no signs of TiLV infection. Challenged tilapia were confirmed as TiLV-positive by RT-qPCR, while challenged carp and walking catfish all tested negative. Overall, our field and laboratory findings indicate that species used in polycultures are not susceptible to TiLV. Although current evidence suggests that TiLV is likely host-specific to tilapia, targeted surveillance for TiLV in other fish species in polyculture systems should continue, in order to prepare for a possible future scenario where TiLV mutates and/or adapts to new host(s).
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Affiliation(s)
- Partho Pratim Debnath
- The International Graduate Course of Veterinary Science and Technology (VST)Faculty of Veterinary ScienceChulalongkorn UniversityBangkokThailand
- Department of Veterinary MicrobiologyCenter of Excellent in Fish Infectious Diseases (CE FID)Faculty of Veterinary ScienceChulalongkorn UniversityBangkokThailand
| | - Nguyen Dinh‐Hung
- Department of Veterinary MicrobiologyCenter of Excellent in Fish Infectious Diseases (CE FID)Faculty of Veterinary ScienceChulalongkorn UniversityBangkokThailand
| | - Suwimon Taengphu
- Fish Health PlatformCenter of Excellence for Shrimp Molecular Biology and Biotechnology (Centex Shrimp)Faculty of ScienceMahidol UniversityBangkokThailand
- National Center for Genetic Engineering and Biotechnology (BIOTEC)National Science and Technology Development Agency (NSTDA)Pathum ThaniThailand
| | | | | | - Saengchan Senapin
- Fish Health PlatformCenter of Excellence for Shrimp Molecular Biology and Biotechnology (Centex Shrimp)Faculty of ScienceMahidol UniversityBangkokThailand
- National Center for Genetic Engineering and Biotechnology (BIOTEC)National Science and Technology Development Agency (NSTDA)Pathum ThaniThailand
| | | | - Ha Thanh Dong
- Department of Food, Agriculture and BioresourcesAquaculture and Aquatic Resources Management ProgramAsian Institute of Technology (AIT)School of EnvironmentKlong LuangPathumthaniThailand
| | - Channarong Rodkhum
- The International Graduate Course of Veterinary Science and Technology (VST)Faculty of Veterinary ScienceChulalongkorn UniversityBangkokThailand
- Department of Veterinary MicrobiologyCenter of Excellent in Fish Infectious Diseases (CE FID)Faculty of Veterinary ScienceChulalongkorn UniversityBangkokThailand
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Barría A, Benzie JAH, Houston RD, De Koning DJ, de Verdal H. Genomic Selection and Genome-wide Association Study for Feed-Efficiency Traits in a Farmed Nile Tilapia ( Oreochromis niloticus) Population. Front Genet 2021; 12:737906. [PMID: 34616434 PMCID: PMC8488396 DOI: 10.3389/fgene.2021.737906] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2021] [Accepted: 08/31/2021] [Indexed: 11/24/2022] Open
Abstract
Nile tilapia is a key aquaculture species with one of the highest production volumes globally. Genetic improvement of feed efficiency via selective breeding is an important goal, and genomic selection may expedite this process. The aims of this study were to 1) dissect the genetic architecture of feed-efficiency traits in a Nile tilapia breeding population, 2) map the genomic regions associated with these traits and identify candidate genes, 3) evaluate the accuracy of breeding value prediction using genomic data, and 4) assess the impact of the genetic marker density on genomic prediction accuracies. Using an experimental video recording trial, feed conversion ratio (FCR), body weight gain (BWG), residual feed intake (RFI) and feed intake (FI) traits were recorded in 40 full-sibling families from the GIFT (Genetically Improved Farmed Tilapia) Nile tilapia breeding population. Fish were genotyped with a ThermoFisher Axiom 65 K Nile tilapia SNP array. Significant heritabilities, ranging from 0.12 to 0.22, were estimated for all the assessed traits using the genomic relationship matrix. A negative but favourable genetic correlation was found between BWG and the feed-efficiency related traits; -0.60 and -0.63 for FCR and RFI, respectively. While the genome-wide association analyses suggested a polygenic genetic architecture for all the measured traits, there were significant QTL identified for BWG and FI on chromosomes seven and five respectively. Candidate genes previously found to be associated with feed-efficiency traits were located in these QTL regions, including ntrk3a, ghrh and eif4e3. The accuracy of breeding value prediction using the genomic data was up to 34% higher than using pedigree records. A SNP density of approximately 5,000 SNPs was sufficient to achieve similar prediction accuracy as the full genotype data set. Our results highlight the potential of genomic selection to improve feed efficiency traits in Nile tilapia breeding programmes.
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Affiliation(s)
- Agustin Barría
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh Easter Bush, Midlothian, United Kingdom
| | - John A. H. Benzie
- WorldFish, Bayan Lepas, Malaysia
- School of Biological Earth and Environmental Sciences, University College Cork, Cork, Ireland
| | - Ross D. Houston
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh Easter Bush, Midlothian, United Kingdom
| | - Dirk-Jan De Koning
- Department of Animal Breeding and Genetics, Swedish University of Agricultural Sciences, Uppsala, Sweden
| | - Hugues de Verdal
- CIRAD, UMR ISEM, Montpellier, France
- ISEM, Univ Montpellier, CNRS, EPHE, IRD, Montpellier, France
- CIRAD, UMR AGAP Institut, Montpellier, France
- UMR AGAP Institut, Univ Montpellier, CIRAD, INRAE, Institut Agro, Montpellier, France
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Phan-Aram P, Mahasri G, Kayansamruaj P, Amparyup P, Srisapoome P. Immune Regulation, but Not Antibacterial Activity, Is a Crucial Function of Hepcidins in Resistance against Pathogenic Bacteria in Nile Tilapia ( Oreochromis niloticus Linn.). Biomolecules 2020; 10:biom10081132. [PMID: 32751990 PMCID: PMC7464455 DOI: 10.3390/biom10081132] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2020] [Revised: 07/20/2020] [Accepted: 07/28/2020] [Indexed: 12/12/2022] Open
Abstract
In this study, the functions of a recombinant propeptide (rProOn-Hep1) and the synthetic FITC-labelled mature peptides sMatOn-Hep1 and sMatOn-Hep2 were analyzed. Moreover, sMatOn-Hep1 and sMatOn-Hep2 were mildly detected in the lymphocytes of peripheral blood mononuclear cells (PBMCs) and strongly detected in head kidney macrophages. The in vitro binding and antibacterial activities of these peptides were slightly effective against several pathogenic bacteria. Immune regulation by sMatOn-Hep1 was also analyzed, and only sMatOn-Hep1 significantly enhanced the phagocytic index in vitro (p < 0.05). Interestingly, intraperitoneal injection of sMatOn-Hep1 (10 or 100 µg) significantly elevated the phagocytic activity, phagocytic index, and lysozyme activity and clearly decreased the iron ion levels in the livers of the treated fish (p < 0.05). Additionally, sMatOn-Hep1 enhanced the expression levels of CC and CXC chemokines, transferrin and both On-Hep genes in the liver, spleen and head kidney, for 1–96 h after injection, but did not properly protect the experimental fish from S. agalactiae infection after 7 days of treatment. However, the injection of S. agalactiae and On-Heps indicated that 100 μg of sMatOn-Hep1 was very effective, while 100 μg of rProOn-Hep1 and sMatOn-Hep2 demonstrated moderate protection. Therefore, On-Hep is a crucial iron-regulating molecule and a key immune regulator of disease resistance in Nile tilapia.
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Affiliation(s)
- Pagaporn Phan-Aram
- Laboratory of Aquatic Animal Health Management, Department of Aquaculture, Faculty of Fisheries, Kasetsart University, 50 Paholayothin Rd, Ladyao, Chatuchak, Bangkok 10900, Thailand; (P.P.-A.); (P.K.)
| | - Gunanti Mahasri
- Department of Fish Health Management and Aquaculture, Faculty of Fisheries and Marine, Universitas Airlangga, Campus C Mulyorejo, Surabaya 60115, Indonesia;
| | - Pattanapon Kayansamruaj
- Laboratory of Aquatic Animal Health Management, Department of Aquaculture, Faculty of Fisheries, Kasetsart University, 50 Paholayothin Rd, Ladyao, Chatuchak, Bangkok 10900, Thailand; (P.P.-A.); (P.K.)
| | - Piti Amparyup
- Marine Biotechnology Research Team, Integrative Aquaculture Biotechnology Research Group, National Center for Genetic Engineering and Biotechnology (BIOTEC), National Science and Technology Development Agency (NSTDA), Pathum Thani 12120, Thailand;
| | - Prapansak Srisapoome
- Laboratory of Aquatic Animal Health Management, Department of Aquaculture, Faculty of Fisheries, Kasetsart University, 50 Paholayothin Rd, Ladyao, Chatuchak, Bangkok 10900, Thailand; (P.P.-A.); (P.K.)
- Correspondence:
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Kumkhong S, Marandel L, Plagnes-Juan E, Veron V, Boonanuntanasarn S, Panserat S. Glucose Injection Into Yolk Positively Modulates Intermediary Metabolism and Growth Performance in Juvenile Nile Tilapia ( Oreochromis niloticus). Front Physiol 2020; 11:286. [PMID: 32362832 PMCID: PMC7181793 DOI: 10.3389/fphys.2020.00286] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2020] [Accepted: 03/16/2020] [Indexed: 12/21/2022] Open
Abstract
The aim of this study was to explore for the first time in omnivorous fish the concept of nutritional programming. A nutritional stimulus was accomplished by microinjecting 2 M glucose into yolk reserves during the alevin stage in Nile tilapia (Oreochromis niloticus). At the molecular level in fry, at 1 week post-injection, glucose stimuli were associated with the up-regulation of genes involved in glycolysis (pklr, hk1, hk2, and pkma), glucose transport (glut4) pathways and down-regulation of genes related to gluconeogenesis (g6pca1, g6pca2, and pck1) and amino acid catabolism (asat, alat) (P < 0.05), demonstrating that the larvae well received the glucose stimulus at a molecular level. Moreover, 20 weeks after glucose injection, early glucose stimuli were always linked to permanent effects in juvenile fish, as reflected by a higher level of glycolytic enzymes [gck, hk1 and hk2 at both mRNA and enzymatic levels and pyruvate kinase (PK) activity]. Finally, the effects of the glucose stimulus history were also examined in fish fed with two different dietary carbohydrate/protein levels (medium-carbohydrate diet, CHO-M; high-carbohydrate diet, CHO-H) in juvenile fish (during weeks 20-24). As expected, the CHO-H diet induced the expression of glycolytic and lipogenic genes (gck, pklr, hk1, hk2, fpkma, fasn, and g6pd) and suppressed the expression of gluconeogenic and amino acid catabolism genes (g6pca1, pck1, pck2, asat, alat, and gdh). Nevertheless, the early glucose stimulus led to persistent up-regulation of glycolytic enzymes (gck, pklr, hk1, and hk2) at both the mRNA and enzyme activity levels and glucose transporter glut4 as well as lower gluconeogenic pck1 gene expression (P < 0.05). More interestingly, the early glucose stimulus was associated with a better growth performance of juvenile fish irrespective of the diets. These permanent changes were associated with DNA hypomethylation in the liver and muscles, suggesting the existence of epigenetic mechanisms at the origin of programming. In conclusion, for the first time in tilapia, early glucose stimuli were found to be clearly associated with a positive metabolic programming effect later in life, improving the growth performance of the fish.
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Affiliation(s)
- Suksan Kumkhong
- School of Animal Technology and Innovation, Institute of Agricultural Technology, Suranaree University of Technology, Nakhon Ratchasima, Thailand
| | - Lucie Marandel
- INRAE, Université de Pau et des Pays de l'Adour, E2S UPPA, Nouméa, France
| | | | - Vincent Veron
- INRAE, Université de Pau et des Pays de l'Adour, E2S UPPA, Nouméa, France
| | - Surintorn Boonanuntanasarn
- School of Animal Technology and Innovation, Institute of Agricultural Technology, Suranaree University of Technology, Nakhon Ratchasima, Thailand
| | - Stephane Panserat
- INRAE, Université de Pau et des Pays de l'Adour, E2S UPPA, Nouméa, France
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Oh WT, Jun JW, Kim HJ, Giri SS, Yun S, Kim SG, Kim SW, Kang JW, Han SJ, Kwon J, Park SC. Characterization and Pathological Analysis of a Virulent Edwardsiella anguillarum Strain Isolated From Nile Tilapia ( Oreochromis niloticus) in Korea. Front Vet Sci 2020; 7:14. [PMID: 32047760 PMCID: PMC6997428 DOI: 10.3389/fvets.2020.00014] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2019] [Accepted: 01/08/2020] [Indexed: 11/18/2022] Open
Abstract
Edwardsiella species are one of the top causative pathogens of mortality in various fisheries worldwide. Their role in zoonotic infections and increase in antibiotic-resistance has raised concerns and interests in many research fields. Similar to the studies investigating human clinical cases, there has been an increase in research examining the potential pathogenic role of the bacterium in aquaculture. Within the Edwardsiella family, Edwardsiella anguillarum was lastest group to be differentiated from the Edwardsiella tarda group, and many studies focusing on the virulence of this species have since ensued. In Korea, only E. tarda infections have been reported in aquaculture industries, and there have been no reports on economic losses incurred owing to E. anguillarum infection. There has been a recent report investigating the pathogenicity and pathological changes caused by E. anguillarum infection in a tilapia farm located in the Costa Rica. To the best of our knowledge, as ours is the first report of E. anguillarum infection in a Nile tilapia (Oreochromis niloticus) farm located in an Asian country, the pathogenicity of the bacterial strain was histopathologically compared to that of the past studies. As tilapia is one of the most globally consumed fish species, particularly throughout Asia, Europe, and America, an epidemiological study regarding the disease distribution is necessary for the control and prevention of the disease. Here, we report the first mass mortality case caused by E. anguillarum infection in a Nile tilapia farm located in Korea; the bacterial strain responsible was isolated, characterized, and pathologically analyzed.
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Affiliation(s)
- Woo Taek Oh
- Laboratory of Aquatic Biomedicine, College of Veterinary Medicine and Research Institute for Veterinary Science, Seoul National University, Seoul, South Korea
| | - Jin Woo Jun
- Department of Aquaculture, Korea National College of Agriculture and Fisheries, Jeonju, South Korea
| | - Hyoun Joong Kim
- Laboratory of Aquatic Biomedicine, College of Veterinary Medicine and Research Institute for Veterinary Science, Seoul National University, Seoul, South Korea
| | - Sib Sankar Giri
- Laboratory of Aquatic Biomedicine, College of Veterinary Medicine and Research Institute for Veterinary Science, Seoul National University, Seoul, South Korea
| | - Saekil Yun
- Laboratory of Aquatic Biomedicine, College of Veterinary Medicine and Research Institute for Veterinary Science, Seoul National University, Seoul, South Korea
| | - Sang Guen Kim
- Laboratory of Aquatic Biomedicine, College of Veterinary Medicine and Research Institute for Veterinary Science, Seoul National University, Seoul, South Korea
| | - Sang Wha Kim
- Laboratory of Aquatic Biomedicine, College of Veterinary Medicine and Research Institute for Veterinary Science, Seoul National University, Seoul, South Korea
| | - Jeong Woo Kang
- Laboratory of Aquatic Biomedicine, College of Veterinary Medicine and Research Institute for Veterinary Science, Seoul National University, Seoul, South Korea
| | - Se Jin Han
- Laboratory of Aquatic Biomedicine, College of Veterinary Medicine and Research Institute for Veterinary Science, Seoul National University, Seoul, South Korea
| | - Jun Kwon
- Laboratory of Aquatic Biomedicine, College of Veterinary Medicine and Research Institute for Veterinary Science, Seoul National University, Seoul, South Korea
| | - Se Chang Park
- Laboratory of Aquatic Biomedicine, College of Veterinary Medicine and Research Institute for Veterinary Science, Seoul National University, Seoul, South Korea
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Liu C, Chang OQ, Zhang DF, Li KB, Wang F, Lin MH, Shi CB, Jiang L, Wang Q, Bergmann SM. Aeromonas shuberti as a cause of multi-organ necrosis in internal organs of Nile tilapia, Oreochromis niloticus. J Fish Dis 2018; 41:1529-1538. [PMID: 30039866 DOI: 10.1111/jfd.12848] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/07/2018] [Revised: 06/06/2018] [Accepted: 06/07/2018] [Indexed: 06/08/2023]
Abstract
A disease with white spots in internal organs of Nile tilapia occurred in Zhanjiang, southern China. Multiple, white nodules, 0.8-2.2 mm in diameter, were scattered throughout the liver, spleen and kidney of diseased fish. Signs of nodules reproduced after artificial infection with the isolated strain. Isolated bacteria were Gram-negative, facultative anaerobic, motile, short rod-shaped, with a length of 1.2-2.2 μm. Morphological and biochemical tests, as well as phylogenetic analysis, all strongly indicated that the isolate from tilapia is identical to Aeromonas schubertii (A. schubertii) which temporary named LF1708 strain. Antibiotic sensitivity assays showed the LF1708 is sensitive to 24 of 27 tested antibiotics. Pathogenicity test revealed that the isolate at the dose of 3.75 × 106 CFU/g killed 100% of experimental tilapia within 2 days and the dose of 1 × 107 CFU/g killed 100% of experimental zebrafish within 1 day. Histopathology of diseased tilapia infected with A. schubertii showed numerous necrotic lesions widely distributed in spleen, liver and kidney, and infiltration with a large number of bacteria. To our knowledge, this was the first report that associated A. schubertii with mortality in tilapia.
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Affiliation(s)
- C Liu
- Key Laboratory of Fishery Drug Development of Ministry of Agriculture, Key Laboratory of Aquatic Animal Immune Technology of Guangdong Province, Pearl River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangdong, China
| | - O Q Chang
- Key Laboratory of Fishery Drug Development of Ministry of Agriculture, Key Laboratory of Aquatic Animal Immune Technology of Guangdong Province, Pearl River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangdong, China
| | - D F Zhang
- Key Laboratory of Fishery Drug Development of Ministry of Agriculture, Key Laboratory of Aquatic Animal Immune Technology of Guangdong Province, Pearl River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangdong, China
| | - K B Li
- Key Laboratory of Fishery Drug Development of Ministry of Agriculture, Key Laboratory of Aquatic Animal Immune Technology of Guangdong Province, Pearl River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangdong, China
| | - F Wang
- Key Laboratory of Fishery Drug Development of Ministry of Agriculture, Key Laboratory of Aquatic Animal Immune Technology of Guangdong Province, Pearl River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangdong, China
| | - M H Lin
- Key Laboratory of Fishery Drug Development of Ministry of Agriculture, Key Laboratory of Aquatic Animal Immune Technology of Guangdong Province, Pearl River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangdong, China
| | - C B Shi
- Key Laboratory of Fishery Drug Development of Ministry of Agriculture, Key Laboratory of Aquatic Animal Immune Technology of Guangdong Province, Pearl River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangdong, China
| | - L Jiang
- Key Laboratory of Fishery Drug Development of Ministry of Agriculture, Key Laboratory of Aquatic Animal Immune Technology of Guangdong Province, Pearl River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangdong, China
| | - Q Wang
- Key Laboratory of Fishery Drug Development of Ministry of Agriculture, Key Laboratory of Aquatic Animal Immune Technology of Guangdong Province, Pearl River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangdong, China
| | - S M Bergmann
- Institute of Infectology, Friedrich-Loffler-Institut (FLI), Federal Research Institute for Animal Health, Greifswald-Insel Riems, Germany
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Osman KM, Ali MN, Radwan I, ElHofy F, Abed AH, Orabi A, Fawzy NM. Dispersion of the Vancomycin Resistance Genes vanA and vanC of Enterococcus Isolated from Nile Tilapia on Retail Sale: A Public Health Hazard. Front Microbiol 2016; 7:1354. [PMID: 27617012 PMCID: PMC4999479 DOI: 10.3389/fmicb.2016.01354] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2016] [Accepted: 08/16/2016] [Indexed: 01/29/2023] Open
Abstract
Although normally regarded harmless commensals, enterococci may cause a range of different infections in humans, including urinary tract infections, sepsis, and endocarditis. The acquisition of vancomycin resistance by enterococci (VRE) has seriously affected the treatment and infection control of these organisms. VRE are frequently resistant to all antibiotics that are effective treatment for vancomycin-susceptible enterococci, which leaves clinicians treating VRE infections with limited therapeutic options. With VRE emerging as a global threat to public health, we aimed to isolate, identify enterococci species from tilapia and their resistance to van-mediated glycopeptide (vanA and vanC) as well as the presence of enterococcal surface protein (esp) using conventional and molecular methods. The cultural, biochemical (Vitek 2 system) and polymerase chain reaction results revealed eight Enterococcus isolates from the 80 fish samples (10%) to be further identified as E. faecalis (6/8, 75%) and E gallinarum (2/8, 25%). Intraperitoneal injection of healthy Nile tilapia with the eight Enterococcus isolates caused significant morbidity (70%) within 3 days and 100% mortality at 6 days post-injection with general signs of septicemia. All of the eight Enterococcus isolates were found to be resistant to tetracycline. The 6/6 E. faecalis isolates were susceptible for penicillin, nitrofurantoin, gentamicin, and streptomycin. On the other hand 5/6 were susceptible for ampicillin, vancomycin, chloramphenicol, and ciprofloxacin. The two isolates of E. gallinarum were sensitive to rifampicin and ciprofloxacin and resistant to vancomycin, chloramphenicol, and erythromycin. Molecular characterization proved that they all presented the prototypic vanC element. On the whole, one of the two vancomycin resistance gene was present in 3/8 of the enterococci isolates, while the esp virulence gene was present in 1/8 of the enterococci isolates. The results in this study emphasize the potential role that aquatic environments are correlated to proximity to anthropogenic activities in determining the antimicrobial resistance patterns of Enterococcus spp. recovered from fish in the river Nile in Giza, Elmounib, Egypt as a continuation of our larger study on the reservoirs of antibiotic resistance in the environment.
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Affiliation(s)
- Kamelia M Osman
- Department of Microbiology, Faculty of Veterinary Medicine, Cairo University, Giza Egypt
| | - Mohamed N Ali
- Department of Fish Diseases and Management, Animal Health Research Institute, Giza Egypt
| | - Ismail Radwan
- Department of Bacteriology, Mycology and Immunology, Faculty of Veterinary Medicine, Beni-Suef University, Beni-Suef Egypt
| | - Fatma ElHofy
- Department of Microbiology, Faculty of Veterinary Medicine, Benha University, Benha Egypt
| | - Ahmed H Abed
- Department of Bacteriology, Mycology and Immunology, Faculty of Veterinary Medicine, Beni-Suef University, Beni-Suef Egypt
| | - Ahmed Orabi
- Department of Microbiology, Faculty of Veterinary Medicine, Cairo University, Giza Egypt
| | - Nehal M Fawzy
- Department of Fish Diseases and Management, Animal Health Research Institute, Giza Egypt
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He J, Gao H, Xu P, Yang R. Genetic parameters for different growth scales in GIFT strain of Nile tilapia (Oreochromis niloticus). J Anim Breed Genet 2015; 132:467-74. [PMID: 25754729 DOI: 10.1111/jbg.12139] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2014] [Accepted: 01/20/2015] [Indexed: 11/28/2022]
Abstract
Body weight, length, width and depth at two growth stages were observed for a total of 5015 individuals of GIFT strain, along with a pedigree including 5588 individuals from 104 sires and 162 dams was collected. Multivariate animal models and a random regression model were used to genetically analyse absolute and relative growth scales of these growth traits. In absolute growth scale, the observed growth traits had moderate heritabilities ranging from 0.321 to 0.576, while pairwise ratios between body length, width and depth were lowly inherited and maximum heritability was only 0.146 for length/depth. All genetic correlations were above 0.5 between pairwise growth traits and genetic correlation between length/width and length/depth varied between both growth stages. Based on those estimates, selection index of multiple traits of interest can be formulated in future breeding program to improve genetically body weight and morphology of the GIFT strain. In relative growth scale, heritabilities in relative growths of body length, width and depth to body weight were 0.257, 0.412 and 0.066, respectively, while genetic correlations among these allometry scalings were above 0.8. Genetic analysis for joint allometries of body weight to body length, width and depth will contribute to genetically regulate the growth rate between body shape and body weight.
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Affiliation(s)
- J He
- Research Centre for Aquatic Biotechnology, Chinese Academy of Fishery Sciences, Beijing, China.,Freshwater Fisheries Research Centre of Chinese Academy of Fishery Sciences, Wuxi, China
| | - H Gao
- School of Fisheries and Life Science, Dalian Ocean University, Dalian, China
| | - P Xu
- Freshwater Fisheries Research Centre of Chinese Academy of Fishery Sciences, Wuxi, China
| | - R Yang
- Research Centre for Aquatic Biotechnology, Chinese Academy of Fishery Sciences, Beijing, China
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