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Souci L, Denesvre C. Interactions between avian viruses and skin in farm birds. Vet Res 2024; 55:54. [PMID: 38671518 PMCID: PMC11055369 DOI: 10.1186/s13567-024-01310-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2024] [Accepted: 03/24/2024] [Indexed: 04/28/2024] Open
Abstract
This article reviews the avian viruses that infect the skin of domestic farm birds of primary economic importance: chicken, duck, turkey, and goose. Many avian viruses (e.g., poxviruses, herpesviruses, Influenza viruses, retroviruses) leading to pathologies infect the skin and the appendages of these birds. Some of these viruses (e.g., Marek's disease virus, avian influenza viruses) have had and/or still have a devasting impact on the poultry economy. The skin tropism of these viruses is key to the pathology and virus life cycle, in particular for virus entry, shedding, and/or transmission. In addition, for some emergent arboviruses, such as flaviviruses, the skin is often the entry gate of the virus after mosquito bites, whether or not the host develops symptoms (e.g., West Nile virus). Various avian skin models, from primary cells to three-dimensional models, are currently available to better understand virus-skin interactions (such as replication, pathogenesis, cell response, and co-infection). These models may be key to finding solutions to prevent or halt viral infection in poultry.
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Affiliation(s)
- Laurent Souci
- Laboratoire de Biologie des Virus Aviaires, UMR1282 ISP, INRAE Centre Val-de-Loire, 37380, Nouzilly, France
| | - Caroline Denesvre
- Laboratoire de Biologie des Virus Aviaires, UMR1282 ISP, INRAE Centre Val-de-Loire, 37380, Nouzilly, France.
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Hofmeister E, Georgousi F, Lund M, Ferro PJ, Flanagan J, Haefele H, Morrow M. Genetic Sequencing of Attwater's Prairie Chicken Avian Poxvirus and Evaluation of Its Potential Role in Reticuloendotheliosis Virus Outbreaks. Avian Dis 2021; 65:414-418. [PMID: 34427416 DOI: 10.1637/0005-2086-65.3.414] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2021] [Accepted: 06/21/2021] [Indexed: 11/05/2022]
Abstract
Efforts to breed Attwater's prairie chickens (APC; Tympanuchus cupido attwateri) in captivity to supplement wild populations of this endangered bird have been negatively affected by infections with Avipoxvirus and reticuloendotheliosis virus (REV). Because REV can be integrated into the genome of fowlpox virus (FPV) and may be transmitted in that manner, identifying the source of avipox disease in APC is important to mitigate the impact of this virus. Tissue samples from APC were collected from breeding programs in Texas from 2016 to 2020. These samples consisted of 11 skin lesions and three internal organs from a total of 14 different birds that died of unknown causes or were euthanized. Avipoxvirus was detected by PCR and isolation in embryonating chicken eggs in all skin lesion samples but was not detected in internal organs. Using sequence analysis of FPV polymerase and 4b genes, we determined that 10 out of 11 Avipoxvirus detections resided within the fowlpox clade and a single sample resided within the canarypox clade. REV sequences were detected in all FPV positive samples and in all internal organ tissues but were not detected in the sample matching the canarypox clade. Analysis of REV sequences and PCR detection showed the REV infecting APC was consistent with REV-A and had little variability on analysis of the U3 region of the long terminal repeat. The results of this study indicate control of REV in APC breeding colonies may benefit by a vaccination program targeting FPV and REV. However, a commercially available vaccine for REV is not available at this time.
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Affiliation(s)
- Erik Hofmeister
- U.S. Geological Survey, National Wildlife Health Center, Madison, WI 53711,
| | - Fiona Georgousi
- U.S. Geological Survey, National Wildlife Health Center, Madison, WI 53711
| | - Melissa Lund
- U.S. Geological Survey, National Wildlife Health Center, Madison, WI 53711
| | - Pamela J Ferro
- Texas A&M Veterinary Medical Diagnostics Laboratory, College Station, TX 77843
| | | | | | - Michael Morrow
- U.S. Fish and Wildlife Service, Attwater Prairie Chicken National Wildlife Refuge, Eagle Lake, TX 77434
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Chacón RD, Astolfi-Ferreira CS, De la Torre DI, de Sá LRM, Piantino Ferreira AJ. An atypical clinicopathological manifestation of fowlpox virus associated with reticuloendotheliosis virus in commercial laying hen flocks in Brazil. Transbound Emerg Dis 2020; 67:2923-2935. [PMID: 32519513 DOI: 10.1111/tbed.13668] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2020] [Revised: 04/08/2020] [Accepted: 05/13/2020] [Indexed: 01/27/2023]
Abstract
Fowlpox (FP) is a common epitheliotropic disease in chickens that is usually controlled by live attenuated vaccines. However, there have been some reports of outbreaks of FP in recent years, even in vaccinated flocks, presenting as atypical lesions and feathering abnormalities in chickens. These findings can be associated with fowlpox virus (FPV) with the reticuloendotheliosis virus (REV) integrated into its genome. In the present study, outbreaks of atypical FP were explored in vaccinated commercial laying hen flocks to determine the nature of the causative agent by histopathologic and molecular approaches. FPV and REV were detected and classified into subclade A1 of the genus Avipoxvirus and subtype 3 of REV (REV3), respectively. Additionally, heterogeneous populations of FPV with partial (containing only a remnant long terminal repeat-LTR) or total (all functional genes) integration of REV were identified by heterologous PCRs and detected considering reference integration sites. These results indicate the mechanism of chimeric genome FPV-REV associated with outbreaks and atypical clinicopathological manifestations in commercial laying hens for the first time in Brazil and in South America. In addition, this study demonstrates the emergence of REV integrated in the FPV genome in Brazilian chicken flocks.
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Affiliation(s)
- Ruy D Chacón
- Department of Pathology, School of Veterinary Medicine, University of São Paulo, São Paulo, Brazil.,Inter-units Program in Biotechnology, University of São Paulo, São Paulo, Brazil
| | | | - David I De la Torre
- Department of Pathology, School of Veterinary Medicine, University of São Paulo, São Paulo, Brazil
| | - Lilian R M de Sá
- Department of Pathology, School of Veterinary Medicine, University of São Paulo, São Paulo, Brazil
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Leeson S, Walsh T. Feathering in commercial poultry II. Factors influencing feather growth and feather loss. WORLD POULTRY SCI J 2019. [DOI: 10.1079/wps20034] [Citation(s) in RCA: 46] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- S. Leeson
- Department of Animal & Poultry Science, University of Guelph, Guelph, Ontario Canada N1G 2W1
| | - T. Walsh
- Novus International, 530 Maryville Ctr. Drive, St. Louis, MO 63141 USA
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Li Y, Wang T, Wang L, Sun M, Cui Z, Chang S, Wu Y, Zhang X, Yu X, Sun T, Zhao P. Assessment on reticuloendotheliosis virus infection in specific-pathogen-free chickens based on detection of yolk antibody. PLoS One 2019; 14:e0213978. [PMID: 31009463 PMCID: PMC6476468 DOI: 10.1371/journal.pone.0213978] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2018] [Accepted: 03/05/2019] [Indexed: 11/19/2022] Open
Abstract
Reticuloendotheliosis virus (REV) is the most frequent exogenous virus that contaminates attenuated vaccines. Therefore, it is extremely important to select REV-free specific-pathogen-free (SPF) chicken embryos. Generally, REV infection is assessed by detecting REV antibodies in SPF chickens. This present study seeks to evaluate REV infection by replacing serum antibody detection with yolk antibody detection. A cohort of 40 nineteen-week-old SPF chickens were artificially inoculated with REV, with 32 SPF chickens raised in another isolation environment served as a blank control. Eggs and serum from 23-week-old chickens were sampled, and yolks were diluted separately to ratios of 1:150, 1:200, 1:300 and 1:400, which were detected together with serum. We found that the yolk antibody detection findings at a dilution of 1:300 had the highest coincidence rate compared with that based on serum antibody measurements. At a dilution ratio of 1:300 for yolk antibody, 72 chickens were continuously observed for 10 weeks from 25- to 34-weeks-old. Our findings were based on serum antibody or yolk antibody detection, and the evaluation results were completely consistent. Therefore, all serum antibody-positive chickens were yolk antibody-positive, and vice versa. Accordingly, vaccine producers can estimate REV cleanliness in a poultry farm by sampling yolk antibody titers.
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Affiliation(s)
- Yang Li
- China Animal Health and Epidemiology Center, Qingdao, China
| | - Tuanjie Wang
- China Institute of Veterinary Drug Control, Beijing, China
| | - Lin Wang
- China Animal Health and Epidemiology Center, Qingdao, China
| | - Mingjun Sun
- China Animal Health and Epidemiology Center, Qingdao, China
| | - Zhizhong Cui
- College of Veterinary Medicine, Shandong Agricultural University, Taian, China
| | - Shuang Chang
- College of Veterinary Medicine, Shandong Agricultural University, Taian, China
| | - Yongping Wu
- College of Animal Sciences and Technology, Zhejiang A&F University, Hangzhou, China
| | - Xiaodong Zhang
- College of Animal Sciences and Technology, Zhejiang A&F University, Hangzhou, China
| | - Xiaohui Yu
- China Animal Health and Epidemiology Center, Qingdao, China
- * E-mail: (TS); (PZ); (XY)
| | - Tao Sun
- Shandong Entry-exit Inspection and Quarantine Bureau, Qingdao, China
- * E-mail: (TS); (PZ); (XY)
| | - Peng Zhao
- College of Veterinary Medicine, Shandong Agricultural University, Taian, China
- * E-mail: (TS); (PZ); (XY)
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Avian Reticuloendotheliosis in Chickens - An Update on Disease Occurrence and Clinical Course. J Vet Res 2018; 62:257-260. [PMID: 30584601 PMCID: PMC6295993 DOI: 10.2478/jvetres-2018-0036] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2018] [Accepted: 08/22/2018] [Indexed: 11/20/2022] Open
Abstract
Avian reticuloendotheliosis (RE) represents an important immunosuppressive disease of poultry. The occurrence of RE in both chickens and turkeys has an immunosuppressive effect and may lead to vaccination failures. Avian reticuloendotheliosis virus (REV) is widely distributed in different kinds of birds, causing subclinical infections. Another important issue adhering to this disease is contamination of vaccines against fowl pox (FP) and Marek’s disease (MD) with REV. The capability of REV to integrate into the genome of other larger DNA viruses complicates its diagnosis and prevention. There are no efficient vaccines against RE nor treatment, which also complicates how to limit its impact on poultry farming. This paper reviews the current state of knowledge of this important immunosuppressive agent of poultry emphasising the importance of this problem in terms of diagnosis of RE.
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Li Y, Fu J, Chang S, Fang L, Cui S, Wang Y, Cui Z, Zhao P. Isolation, identification, and hexon gene characterization of fowl adenoviruses from a contaminated live Newcastle disease virus vaccine. Poult Sci 2017; 96:1094-1099. [DOI: 10.3382/ps/pew405] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2016] [Accepted: 10/15/2016] [Indexed: 12/16/2022] Open
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Li Y, Cui S, Cui Z, Chang S, Zhao P. Genome analysis and pathogenicity of reticuloendotheliosis virus isolated from a contaminated vaccine seed against infectious bursal disease virus: first report in China. J Gen Virol 2016; 97:2809-2815. [PMID: 27609617 DOI: 10.1099/jgv.0.000588] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Specific-pathogen-free (SPF) chickens were inoculated with the virus seed of an infectious bursal disease virus (IBDV)-attenuated vaccine, and positive reticuloendotheliosis virus (REV) antibody levels were subsequently detected in the chicken sera, indicating potential REV contamination of the vaccine. After neutralization with IBDV-positive blood serum, the vaccine was inoculated into DF-1 cells for REV isolation and identification. An REV strain, designated IBD-C1605, was identified using an immunofluorescence assay test. Three pairs of primers were employed for the amplification, cloning and sequencing of three overlapping fragments of the IBD-C1605 genome, and the whole-genome sequence of this isolate was obtained after gene assembly. The genome was 8362 base pairs (nt) in length and its homology with the nucleotide sequences of different reference strains varied between 94.2 and 99.2 %. Isolate IBD-C1605 was inoculated into 1-day-old SPF chickens to observe its pathogenicity. Infection with this organism slowed down the weight gain of SPF chickens and caused atrophy of their immune organs, such as the bursa of Fabricius and thymus gland. Furthermore, the chicken antibody levels decreased significantly after Newcastle disease virus and avian influenza virus subtype H9 vaccine immunization. This is the first report on the isolation and identification of REV from attenuated vaccine virus seeds in China, and is also the first study on the pathogenicity of REV from a contaminated vaccine in China. Our findings contribute towards a better understanding of the detrimental effects of vaccine contamination with exogenous viruses such as REV.
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Affiliation(s)
- Yang Li
- College of Animal Science and Veterinary Medicine, Shandong Agricultural University, Tai'an 271018, PR China
| | - Shuai Cui
- College of Animal Science and Veterinary Medicine, Shandong Agricultural University, Tai'an 271018, PR China
| | - Zhizhong Cui
- College of Animal Science and Veterinary Medicine, Shandong Agricultural University, Tai'an 271018, PR China
| | - Shuang Chang
- College of Animal Science and Veterinary Medicine, Shandong Agricultural University, Tai'an 271018, PR China
| | - Peng Zhao
- College of Animal Science and Veterinary Medicine, Shandong Agricultural University, Tai'an 271018, PR China
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Luan H, Wang Y, Li Y, Cui Z, Chang S, Zhao P. Development of a real-time quantitative RT-PCR to detect REV contamination in live vaccine. Poult Sci 2016; 95:2023-9. [DOI: 10.3382/ps/pew147] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/27/2016] [Indexed: 11/20/2022] Open
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10
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El-Abasy MA, El-Gohary AEGA, El-Sawy A, M. Hafez H, El-Adawy H. Histopathological and Serological Diagnosis of Avian Reticuloendotheliosis in Cross-bred Chicken Farms in Delta Egypt. ASIAN JOURNAL OF ANIMAL AND VETERINARY ADVANCES 2016; 11:272-279. [DOI: 10.3923/ajava.2016.272.279] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/02/2023]
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Hu F, Zhao Y, Qi X, Cui H, Gao Y, Gao H, Liu C, Wang Y, Zhang Y, Li K, Wang X, Wang Y. Soluble expression and enzymatic activity evaluation of protease from reticuloendotheliosis virus. Protein Expr Purif 2015; 114:64-70. [PMID: 26102339 DOI: 10.1016/j.pep.2015.06.010] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2015] [Revised: 05/11/2015] [Accepted: 06/17/2015] [Indexed: 11/26/2022]
Abstract
The protease (PR) encoded by most retroviruses is deeply involved in the lifecycle and infection process of retroviruses by possessing the specificity necessary to correctly cleave the viral polyproteins and host cell proteins. However, as an important representative of avian retroviruses, the enzymatic properties of PR from reticuloendotheliosis virus (REV) have not been clearly documented. The recombinant PR, its mutant fused with a His-tag, and its substrate p18-p30 fused with a GST-tag were expressed in the Escherichia coli system as soluble enzymes. The soluble PR and p18-p30 were purified using Ni-NTA His Bind Resin and Glutathione Sepharose 4B, respectively. The enzymatic activity of PR was analyzed using the substrate of p18-p30. The expressed prokaryotic protease has enzyme activity that is dependent on such conditions as temperature, pH, and ions, and its activity can be inhibited by caspase inhibitor and the divalent metal ions Ca(2+) and Ni(2+). In addition, the key role of the residue Thr (amino acids 28) for the enzymatic activity of PR was identified. Furthermore, the caspase inhibitor Z-VAD-FMK was confirmed to inhibit the PR enzymatic activity of REV. For the first time, the PR of REV was expressed in the soluble form, and the optimal enzymatic reaction system in vitro was developed and preliminarily used. This study provides essential tools and information for further understanding the infection mechanism of REV and for the development of antiviral drugs treating retroviruses.
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Affiliation(s)
- Feng Hu
- Division of Avian Infectious Diseases, State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, The Chinese Academy of Agricultural Sciences, Harbin 150001, China.
| | - Yan Zhao
- Division of Avian Infectious Diseases, State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, The Chinese Academy of Agricultural Sciences, Harbin 150001, China.
| | - Xiaole Qi
- Division of Avian Infectious Diseases, State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, The Chinese Academy of Agricultural Sciences, Harbin 150001, China.
| | - Hongyu Cui
- Division of Avian Infectious Diseases, State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, The Chinese Academy of Agricultural Sciences, Harbin 150001, China.
| | - Yulong Gao
- Division of Avian Infectious Diseases, State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, The Chinese Academy of Agricultural Sciences, Harbin 150001, China.
| | - Honglei Gao
- Division of Avian Infectious Diseases, State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, The Chinese Academy of Agricultural Sciences, Harbin 150001, China.
| | - Changjun Liu
- Division of Avian Infectious Diseases, State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, The Chinese Academy of Agricultural Sciences, Harbin 150001, China.
| | - Yongqiang Wang
- Division of Avian Infectious Diseases, State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, The Chinese Academy of Agricultural Sciences, Harbin 150001, China.
| | - Yanping Zhang
- Division of Avian Infectious Diseases, State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, The Chinese Academy of Agricultural Sciences, Harbin 150001, China.
| | - Kai Li
- Division of Avian Infectious Diseases, State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, The Chinese Academy of Agricultural Sciences, Harbin 150001, China.
| | - Xiaomei Wang
- Division of Avian Infectious Diseases, State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, The Chinese Academy of Agricultural Sciences, Harbin 150001, China; Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Disease and Zoonoses, Yangzhou 225009, China.
| | - Yunfeng Wang
- Division of Avian Infectious Diseases, State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, The Chinese Academy of Agricultural Sciences, Harbin 150001, China; National Engineering Research Center of Veterinary Biologics, Harbin, China.
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Gilhare VR, Hirpurkar SD, Kumar A, Naik SK, Sahu T. Pock forming ability of fowl pox virus isolated from layer chicken and its adaptation in chicken embryo fibroblast cell culture. Vet World 2015; 8:245-50. [PMID: 27047081 PMCID: PMC4774827 DOI: 10.14202/vetworld.2015.245-250] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2014] [Revised: 01/13/2015] [Accepted: 01/20/2015] [Indexed: 11/16/2022] Open
Abstract
Aim: The objective of the present study was to examine pock forming ability of field strain and vaccine strain of fowl pox virus (FPV) in chorioallantoic membrane (CAM) of embryonated chicken eggs and its adaptation in chicken embryo fibroblast (CEF) cell culture. Materials and Methods: Dry scabs were collected from 25 affected birds in glycerin-saline and preserved at 4°C until processed. Virus was isolated in 10-day-old embryonated chicken eggs by dropped CAM method. The identity of the virus is confirmed by clinical findings of affected birds, pock morphology and histopathology of infected CAM. In addition one field isolate and vaccine strain of FPV was adapted to CEF cell culture. CEF cell culture was prepared from 9-day-old embryonated chicken eggs. Result: Clinical symptoms observed in affected birds include pox lesion on comb, wattle, eyelids and legs, no internal lesions were observed. All field isolates produced similar findings in CAM. Pocks produced by field isolates ranged from 3 mm to 5 mm at the third passage while initial passages edematous thickening and necrosis of CAM was observed. Pocks formed by lyophilized strain were ranges from 0.5 mm to 2.5 mm in diameter scattered all over the membrane at the first passage. Intra-cytoplasmic inclusion bodies are found on histopathology of CAM. At third passage level, the CEF inoculated with FPV showed characteristic cytopathic effect (CPE) included aggregation of cells, syncytia and plaque formation. Conclusion: FPV field isolates and vaccine strain produced distinct pock lesions on CAMs. Infected CAM showed intracytoplasmic inclusion bodies. The CEF inoculated with FPV field isolate as well as a vaccine strain showed characteristic CPE at third passage level.
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Affiliation(s)
- Varsha Rani Gilhare
- Department of Veterinary Microbiology, College of Veterinary Science and Animal Husbandry, Anjora Durg, Chhattisgarh, India
| | - S D Hirpurkar
- Department of Veterinary Microbiology, College of Veterinary Science and Animal Husbandry, Anjora Durg, Chhattisgarh, India
| | - Ashish Kumar
- Department of Veterinary Microbiology, College of Veterinary Science and Animal Husbandry, Anjora Durg, Chhattisgarh, India
| | - Surendra Kumar Naik
- Department of Animal Nutrition, College of Veterinary Science and Animal Husbandry, Anjora Durg, Chhattisgarh, India
| | - Tarini Sahu
- Department of Animal Nutrition, College of Veterinary Science and Animal Husbandry, Anjora Durg, Chhattisgarh, India
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Woźniakowski G, Mamczur A, Samorek-Salamonowicz E. Common occurrence of Gallid herpesvirus-2 with reticuloendotheliosis virus in chickens caused by possible contamination of vaccine stocks. J Appl Microbiol 2015; 118:803-8. [PMID: 25641090 DOI: 10.1111/jam.12734] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2014] [Revised: 12/19/2014] [Accepted: 12/19/2014] [Indexed: 11/28/2022]
Abstract
AIMS The aim of this study was to investigate the common occurrence of reticuloendotheliosis virus (REV) among Gallid herpesvirus 2 (GaHV-2) infected chickens. The possible cause of this co-occurrence may be linked to contaminated vaccine stocks, which were also examined. METHODS AND RESULTS The study was conducted on 25 field isolates of GaHV-2 collected between 2007 and 2013 from vaccinated chickens. Additionally, 10 commercial Marek's Disease vaccine stocks manufactured between 1993 and 2013, comprising of FC126 HVT, CVI988/Rispens and bivalent HVT + Rispens vaccines were examined. Chicken isolates were collected from the liver. Due to difficulties in differentiation between GaHV-2 and REV, by observation of clinical signs or lesions presented in liver or spleen, loop-mediated isothermal amplification (LAMP and RT-LAMP) as well as PCR-based methods were applied. CONCLUSIONS The co-occurrence of GaHV-2 and REV genetic material was shown in 24 (96%) of 25 examined isolates. A marginal REV contamination was detected in three out 10 (30%) commercial vaccine stocks, mainly in bivalent HVT + Rispens vaccines produced between 2009 and 2012. SIGNIFICANCE AND IMPACT OF THE STUDY Our results indicated the common occurrence of GaHV-2 and REV in Polish chicken flocks, which is probably linked to contaminated HVT + Rispens vaccine stocks. Reasons for the detection of a marginal REV contamination need to be further elucidated.
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Affiliation(s)
- G Woźniakowski
- Department of Poultry Viral Diseases, National Veterinary Research Institute, Puławy, Poland
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14
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Koo BS, Lee HR, Jeon EO, Jang HS, Han MS, Min KC, Lee SB, Kim JJ, Mo IP. An outbreak of lymphomas in a layer chicken flock previously infected with fowlpox virus containing integrated reticuloendotheliosis virus. Avian Dis 2014; 57:812-7. [PMID: 24597128 DOI: 10.1637/10551-041113-case.r1] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Visceral lymphomas occurred in a 236-day-old layer flock previously diagnosed with reticuloendotheliosis virus (REV)-integrated fowlpox virus (FPV) infection at the age of 77 days. Common pathologic lesions were multiple neoplastic nodules of homogeneous lymphocytes in the livers and spleens of all submitted chickens. All neoplastic tissues were positive for the REV envelope (env) gene by PCR. In a retrospective molecular study of FPV-infected 77-day-old chickens from the same flock, we identified nearly full-length REV provirus integrated into the genome of FPV as well as the REV env gene in trachea samples, whereas only the REV LTR region was present in the FPV strain used to vaccinate this flock. The 622-bp REV env gene nucleotide sequence derived from the trachea and neoplastic tissues was identical. Commercial ELISA of serum samples revealed that all chickens aged between 17 and 263 days in this flock were positive for REV but not for avian leukosis virus. Taken together, the evidence suggests that the visceral lymphomas were caused by a REV-integrated FPV field strain. FPV infections of commercial chickens should be followed up by careful monitoring for manifestations of REV infection, including lymphomas and immune depression, considering the ease with which the REV provirus appears to be able to integrate into the FPV genome.
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Affiliation(s)
- B S Koo
- Avian Disease Laboratory, College of Veterinary Medicine, Chungbuk National University, Cheongju, 361-763, Korea
| | - H R Lee
- Avian Disease Laboratory, College of Veterinary Medicine, Chungbuk National University, Cheongju, 361-763, Korea
| | - E O Jeon
- Avian Disease Laboratory, College of Veterinary Medicine, Chungbuk National University, Cheongju, 361-763, Korea
| | - H S Jang
- Avian Disease Laboratory, College of Veterinary Medicine, Chungbuk National University, Cheongju, 361-763, Korea
| | - M S Han
- Avian Disease Laboratory, College of Veterinary Medicine, Chungbuk National University, Cheongju, 361-763, Korea
| | - K C Min
- Avian Disease Laboratory, College of Veterinary Medicine, Chungbuk National University, Cheongju, 361-763, Korea
| | - S B Lee
- Avian Disease Laboratory, College of Veterinary Medicine, Chungbuk National University, Cheongju, 361-763, Korea
| | - J J Kim
- Avian Disease Laboratory, College of Veterinary Medicine, Chungbuk National University, Cheongju, 361-763, Korea
| | - I P Mo
- Avian Disease Laboratory, College of Veterinary Medicine, Chungbuk National University, Cheongju, 361-763, Korea
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Karpińska T, Kozaczyński W, Niemczuk K, Jasik A, Kycko A, Reichert M. Mixed infection by fowlpox virus and Chlamydophila psittaci in a commercial laying hen flock. Acta Vet Hung 2014; 62:42-51. [PMID: 23974932 DOI: 10.1556/avet.2013.038] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
An outbreak of fowlpox occurred in a commercial laying hen flock in one of the western provinces of Poland. Clinical signs suggested fowlpox and the diagnosis was confirmed by histopathological detection of Bollinger bodies within the epithelial cells. Detailed ultrastructural examination revealed an additional concurrent infection with chlamydia-like particles. The particles were identified by PCR as fowlpox virus and Chlamydophila psittaci. It is worth noting that both pathogens can generate morphologic forms capable of prolonged survival and inducing latent and persistent infection. We suggest a possible interaction between the two pathogens on ultrastructural level and assess the clinical consequences of the mixed infection. This study also demonstrates a potential of the transmission electron microscope (TEM) for identifying a superinfection with another pathogen (in this case C. psittaci), which may remain undetected by routine techniques.
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Affiliation(s)
| | | | - Krzysztof Niemczuk
- 2 National Veterinary Research Institute — State Veterinary Institute Puławy Poland
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Existence of variant strains Fowlpox virus integrated with Reticuloendotheliosis virus in its genome in field isolates in Tanzania. Trop Anim Health Prod 2014; 46:711-6. [PMID: 24557589 DOI: 10.1007/s11250-014-0552-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/03/2014] [Indexed: 10/25/2022]
Abstract
Fowlpox virus (FPV) is one example of poultry viruses which undergoes recombination with Reticuloendotheliosis virus (REV). Trepidation had been raised, and it was well established on augmented pathogenicity of the FPV upon integration of the full intact REV. In this study, we therefore intended at assessing the integration of REV into FPV genome of the field isolates obtained in samples collected from different regions of Tanzania. DNA extraction of 85 samples (scabs) was performed, and FPV-specific PCR was done by the amplification of the highly conserved P4b gene. Evaluation of FPV-REV recombination was done to FPV-specific PCR positively identified samples by amplifying the env gene and REV long terminal repeats (5' LTR). A 578-bp PCR product was amplified from 43 samples. We are reporting for the first time in Tanzania the existence of variant stains of FPV integrated with REV in its genome as 65 % of FPV identified isolates were having full intact REV integration, 21 % had partial FPV-REV env gene integration and 5 % had partial 5' LTR integration. Despite of the fact that FPV-REV integrated stains prevailed, FPV-REV-free isolates (9 %) also existed. In view of the fact that full intact REV integration is connected with increased pathogenicity of FPV, its existence in the FPV genome of most field isolates could have played a role in increased endemic, sporadic and recurring outbreaks in selected areas in Tanzania.
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17
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Abstract
Subclinical immunosuppression in chickens is an important but often underestimated factor in the subsequent development of clinical disease. Immunosuppression can be caused by pathogens such as chicken infectious anemia virus, infectious bursal disease virus, reovirus, and some retroviruses (e.g., reticuloendotheliosis virus). Mycotoxins and stress, often caused by poor management practices, can also cause immunosuppression. The effects on the innate and acquired immune responses and the mechanisms by which mycotoxins, stress and infectious agents cause immunosuppression are discussed. Immunoevasion is a common ploy by which viruses neutralize or evade immune responses. DNA viruses such as herpesvirus and poxvirus have multiple genes, some of them host-derived, which interfere with effective innate or acquired immune responses. RNA viruses may escape acquired humoral and cellular immune responses by mutations in protective antigenic epitopes (e.g., avian influenza viruses), while accessory non-structural proteins or multi-functional structural proteins interfere with the interferon system (e.g., Newcastle disease virus).
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Niewiadomska AM, Gifford RJ. The extraordinary evolutionary history of the reticuloendotheliosis viruses. PLoS Biol 2013; 11:e1001642. [PMID: 24013706 PMCID: PMC3754887 DOI: 10.1371/journal.pbio.1001642] [Citation(s) in RCA: 70] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2013] [Accepted: 07/19/2013] [Indexed: 11/18/2022] Open
Abstract
The reticuloendotheliosis viruses (REVs) comprise several closely related amphotropic retroviruses isolated from birds. These viruses exhibit several highly unusual characteristics that have not so far been adequately explained, including their extremely close relationship to mammalian retroviruses, and their presence as endogenous sequences within the genomes of certain large DNA viruses. We present evidence for an iatrogenic origin of REVs that accounts for these phenomena. Firstly, we identify endogenous retroviral fossils in mammalian genomes that share a unique recombinant structure with REVs-unequivocally demonstrating that REVs derive directly from mammalian retroviruses. Secondly, through sequencing of archived REV isolates, we confirm that contaminated Plasmodium lophurae stocks have been the source of multiple REV outbreaks in experimentally infected birds. Finally, we show that both phylogenetic and historical evidence support a scenario wherein REVs originated as mammalian retroviruses that were accidentally introduced into avian hosts in the late 1930s, during experimental studies of P. lophurae, and subsequently integrated into the fowlpox virus (FWPV) and gallid herpesvirus type 2 (GHV-2) genomes, generating recombinant DNA viruses that now circulate in wild birds and poultry. Our findings provide a novel perspective on the origin and evolution of REV, and indicate that horizontal gene transfer between virus families can expand the impact of iatrogenic transmission events.
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Affiliation(s)
| | - Robert J. Gifford
- Aaron Diamond AIDS Research Center, New York, New York, United States of America
- * E-mail:
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19
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Buscaglia C. Mixed infections of Marek's disease and reticuloendotheliosis viruses in layer flocks in Argentina. Avian Dis 2013; 57:569-71. [PMID: 23901777 DOI: 10.1637/10398-100112-case.1] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
The presence of reticuloendotheliosis virus (REV) was examined in flocks affected with Marek's disease (MD). Sera were positive to REV antibodies by agar gel precipitation. However, these findings were not conclusive since fowlpox vaccines can have REV fragments or the whole genome inserted. Frozen sections from tumors were positive for MD virus (MDV) but negative for REV. Chicken embryo fibroblast (CEF) and chicken kidney cell (CKC) culture inoculated with buffy coat cells or blood from the affected birds were examined. Positive cells were shown for REV and MDV by fluorescent antibodies tests in CEF and CKC, respectively, indicating the presence of REV in Argentinean layer flocks. This is the first report of REV in Argentina and also in South America.
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Affiliation(s)
- Celina Buscaglia
- Comisión de Investigaciones Científicas de la Provincia Buenos Aires, Argentina.
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Singh P, Kim TJ, Tripathy DN. Re-emerging fowlpox: evaluation of isolates from vaccinated flocks. Avian Pathol 2012; 29:449-55. [PMID: 19184837 DOI: 10.1080/030794500750047207] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
Abstract
Vaccines of fowlpox or pigeonpox virus origin have been routinely used for more than half a century to prevent fowlpox in commercial poultry in areas where the disease is endemic. However, in recent years, outbreaks of fowlpox have occurred in previously vaccinated flocks. One possible explanation for this problem is the emergence of variant strains of fowlpox virus (FPV). A second, not mutually exclusive, postulate is that the novel FPV exhibit enhanced virulence due to the integration of avian reticuloendotheliosis virus (REV) into their genomes. To determine if immunological variance and/or the acquisition of REV nucleotide sequences could be responsible for the ineffectiveness of current vaccines, the ability of two commercial vaccine viruses and four, recently isolated, field strains to protect chickens against challenge with one of the more virulent field viruses was evaluated. Adequate protection was provided by the vaccines and two of the four field isolates. Interestingly, the two isolates that were not protective, as well as the challenge strain, failed to elicit a strong humoral antibody response. As to possible REV participation, an antibody response to this virus was only found in those chickens receiving one of the ''protective'' field strains, despite the presence of REV coding sequences in all four field viruses. While REV long terminal repeats of variable lengths were detected in the genomes of all FPV strains used in this study, only the DNAs of the field strains appeared to have intact REV provirus. This retention of foreign DNA may enhance the pathogenesis of FPV, although other factors may be involved.
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Affiliation(s)
- P Singh
- Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
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21
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Weli SC, Tryland M. Avipoxviruses: infection biology and their use as vaccine vectors. Virol J 2011; 8:49. [PMID: 21291547 PMCID: PMC3042955 DOI: 10.1186/1743-422x-8-49] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2010] [Accepted: 02/03/2011] [Indexed: 11/21/2022] Open
Abstract
Avipoxviruses (APVs) belong to the Chordopoxvirinae subfamily of the Poxviridae family. APVs are distributed worldwide and cause disease in domestic, pet and wild birds of many species. APVs are transmitted by aerosols and biting insects, particularly mosquitoes and arthropods and are usually named after the bird species from which they were originally isolated. The virus species Fowlpox virus (FWPV) causes disease in poultry and associated mortality is usually low, but in flocks under stress (other diseases, high production) mortality can reach up to 50%. APVs are also major players in viral vaccine vector development for diseases in human and veterinary medicine. Abortive infection in mammalian cells (no production of progeny viruses) and their ability to accommodate multiple gene inserts are some of the characteristics that make APVs promising vaccine vectors. Although abortive infection in mammalian cells conceivably represents a major vaccine bio-safety advantage, molecular mechanisms restricting APVs to certain hosts are not yet fully understood. This review summarizes the current knowledge relating to APVs, including classification, morphogenesis, host-virus interactions, diagnostics and disease, and also highlights the use of APVs as recombinant vaccine vectors.
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Affiliation(s)
- Simon C Weli
- National Veterinary Institute, Ullevålsveien 68, N-0106 Oslo, Norway.
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Dittmar T, Zänker KS. Horizontal gene transfers with or without cell fusions in all categories of the living matter. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2011; 714:5-89. [PMID: 21506007 PMCID: PMC7120942 DOI: 10.1007/978-94-007-0782-5_2] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
This article reviews the history of widespread exchanges of genetic segments initiated over 3 billion years ago, to be part of their life style, by sphero-protoplastic cells, the ancestors of archaea, prokaryota, and eukaryota. These primordial cells shared a hostile anaerobic and overheated environment and competed for survival. "Coexist with, or subdue and conquer, expropriate its most useful possessions, or symbiose with it, your competitor" remain cellular life's basic rules. This author emphasizes the role of viruses, both in mediating cell fusions, such as the formation of the first eukaryotic cell(s) from a united crenarchaeon and prokaryota, and the transfer of host cell genes integrated into viral (phages) genomes. After rising above the Darwinian threshold, rigid rules of speciation and vertical inheritance in the three domains of life were established, but horizontal gene transfers with or without cell fusions were never abolished. The author proves with extensive, yet highly selective documentation, that not only unicellular microorganisms, but the most complex multicellular entities of the highest ranks resort to, and practice, cell fusions, and donate and accept horizontally (laterally) transferred genes. Cell fusions and horizontally exchanged genetic materials remain the fundamental attributes and inherent characteristics of the living matter, whether occurring accidentally or sought after intentionally. These events occur to cells stagnating for some 3 milliard years at a lower yet amazingly sophisticated level of evolution, and to cells achieving the highest degree of differentiation, and thus functioning in dependence on the support of a most advanced multicellular host, like those of the human brain. No living cell is completely exempt from gene drains or gene insertions.
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Affiliation(s)
- Thomas Dittmar
- Inst. Immunologie, Universität Witten/Herdecke, Stockumer Str. 10, Witten, 58448 Germany
| | - Kurt S. Zänker
- Institute of Immunologie, University of Witten/Herdecke, Stockumer Str. 10, Witten, 58448 Germany
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Awad AM, Abd El-Hamid HS, Abou Rawash AA, Ibrahim HH. Detection of reticuloendotheliosis virus as a contaminant of fowl pox vaccines. Poult Sci 2010; 89:2389-95. [PMID: 20952701 DOI: 10.3382/ps.2010-00899] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
This study was designed to detect reticuloendotheliosis virus (REV) as a contaminant in fowl pox vaccines. A total of 30 fowl pox vaccine samples were examined for the presence of REV using both in vitro and in vivo methods. In in vitro testing, the fowl pox vaccine samples were inoculated into chicken embryo fibroblast cultures prepared from specific-pathogen-free embryonated chicken eggs, and the cultures were examined using PCR to detect REV. In in vivo testing, each fowl pox vaccine sample was inoculated into 5-d-old specific-pathogen-free chicks, which were kept under observation for up to 12 wk postinoculation; serum samples were collected at 15, 30, and 45 d postinoculation for the detection of REV-specific antibodies using ELISA. Tissue samples were collected at 8 and 12 wk postinoculation for histopathological examination. Of the tested vaccines, only one imported vaccine sample tested positive for REV using PCR. Serum samples collected from chicks infected with the PCR-positive vaccine batch also tested positive for REV-specific antibodies using ELISA. Histopathological examination of the liver, spleen, and bursa of Fabricius demonstrated the presence of tumor cells in these organs, confirming the results obtained using PCR and ELISA, and indicating that the sample was contaminated with REV. These data clearly indicate that the screening of all commercial poultry vaccines for viruses is an important factor in assuring the biosafety of animal vaccines.
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Affiliation(s)
- A M Awad
- Department of Avian and Aquatic Animal Medicine, Faculty of Veterinary Medicine, Alexandria University, Behera, Egypt 22758.
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24
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Diallo IS, Taylor J, Gibson J, Hoad J, De Jong A, Hewitson G, Corney BG, Rodwell BJ. Diagnosis of a naturally occurring dual infection of layer chickens with fowlpox virus and gallid herpesvirus 1 (infectious laryngotracheitis virus). Avian Pathol 2010; 39:25-30. [DOI: 10.1080/03079450903447412] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Affiliation(s)
- Ibrahim S. Diallo
- a Biosecurity Sciences Laboratory, Queensland Primary Industries and Fisheries, Department of Employment, Economic Development and Innovation Locked Bag 4 , Moorooka , 4105 , Australia
| | - Jim Taylor
- b Animal Disease Surveillance Laboratory, Queensland Primary Industries and Fisheries, Department of Employment, Economic Development and Innovation , Tor St Complex, Toowoomba , Australia
| | - John Gibson
- b Animal Disease Surveillance Laboratory, Queensland Primary Industries and Fisheries, Department of Employment, Economic Development and Innovation , Tor St Complex, Toowoomba , Australia
| | - John Hoad
- a Biosecurity Sciences Laboratory, Queensland Primary Industries and Fisheries, Department of Employment, Economic Development and Innovation Locked Bag 4 , Moorooka , 4105 , Australia
| | - Amanda De Jong
- a Biosecurity Sciences Laboratory, Queensland Primary Industries and Fisheries, Department of Employment, Economic Development and Innovation Locked Bag 4 , Moorooka , 4105 , Australia
| | - Glen Hewitson
- a Biosecurity Sciences Laboratory, Queensland Primary Industries and Fisheries, Department of Employment, Economic Development and Innovation Locked Bag 4 , Moorooka , 4105 , Australia
| | - Bruce G. Corney
- a Biosecurity Sciences Laboratory, Queensland Primary Industries and Fisheries, Department of Employment, Economic Development and Innovation Locked Bag 4 , Moorooka , 4105 , Australia
| | - Barry J. Rodwell
- a Biosecurity Sciences Laboratory, Queensland Primary Industries and Fisheries, Department of Employment, Economic Development and Innovation Locked Bag 4 , Moorooka , 4105 , Australia
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25
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Multiplication of HVT FC-126 (Herpesvirus turkey) virus in the kidney cell lines of no avian origin. ACTA VET-BEOGRAD 2010. [DOI: 10.2298/avb1004381f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
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26
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Wambura PN, Godfrey SK. Protective immune response of chickens to oral vaccination with thermostable live Fowlpox virus vaccine (strain TPV-1) coated on oiled rice. Trop Anim Health Prod 2009; 42:451-6. [PMID: 19714476 DOI: 10.1007/s11250-009-9442-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2009] [Accepted: 08/14/2009] [Indexed: 10/20/2022]
Abstract
The objective of the present study was to develop and evaluate a local vaccine (strain TPV-1) against Fowl pox (FP) in chickens. Two separate groups of chickens were vaccinated with FP vaccine through oral (coated on oiled rice) and wing web stab routes, respectively. The results showed that the haemagglutination-inhibition (HI) antibody titres in both vaccinated groups were comparable and significantly higher (P < 0.05) than the control chickens. It was further revealed that 14 days after vaccination HI GMT of > or =2 log(2) was recorded in chickens vaccinated by oral and wing web stab routes whereas 35 days after vaccination the HI antibody titres reached 5.6 log(2) and 6.3 log(2), respectively. Moreover, in both groups the birds showed 100% protection against challenge virus at 35 days after vaccination. The findings from the present study have shown that oral route is equally effective as wing web stab route for vaccination of chickens against FP. However, the oral route can be used in mass vaccination of birds thus avoid catching individual birds for vaccination. It was noteworthy that strain TPV-1 virus could be propagated by a simple allantoic cavity inoculation and harvesting of allantoic fluid where it survived exposure at 57 degrees C for 2 hours. If the oral vaccination technique is optimized it may be used in controlling FP in scavenging and feral chickens. In conclusion, the present study has shown that FP vaccine (strain TPV-1) was safe, thermostable, immunogenic and efficacious in vaccinated chickens.
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Affiliation(s)
- Philemon N Wambura
- Department of Veterinary Microbiology and Parasitology, Sokoine University of Agriculture, PO Box 3019, Chuo Kikuu, Morogoro, Tanzania.
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Davidson I, Shkoda I, Perk S. Integration of the reticuloendotheliosis virus envelope gene into the poultry fowlpox virus genome is not universal. J Gen Virol 2008; 89:2456-2460. [DOI: 10.1099/vir.0.2008/001313-0] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/30/2023] Open
Abstract
Fowlpox virus (FWPV) is found worldwide in poultry and wild birds. FWPV is a natural example of recombination between viruses, as reticuloendotheliosis virus (REV) fragments have been found in all poultry FWPVs and these are implicated in virulence alteration. We aimed to determine the commonality of this phenomenon and analysed FWPVs collected from 128 poultry flocks and birds over the last 10 years. Various fragments of both viruses were amplified and sequenced at the FWPV integration site, located between FWPV open reading frames 201 and 203. Seven isolates were found to contain no REV insertions, including fragments of the REV env, gag and 5′ REV-long terminal repeat (LTR). We demonstrate here for the first time, the existence of poultry FWPVs without REV inserts (two from chickens, one from turkey FWPV and four from wild birds). The REV inserts were heterogeneous in size. In addition to poultry and wild bird isolates, three FWPV vaccine virus strains were examined and found to contain only remnant REV-LTR and no REV envelope gene fragments.
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Affiliation(s)
- Irit Davidson
- Division of Avian and Fish Diseases, Kimron Veterinary Institute, PO Box 12, Bet Dagan 50250, Israel
| | - Irena Shkoda
- Division of Avian and Fish Diseases, Kimron Veterinary Institute, PO Box 12, Bet Dagan 50250, Israel
| | - Shimon Perk
- Division of Avian and Fish Diseases, Kimron Veterinary Institute, PO Box 12, Bet Dagan 50250, Israel
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Tadese T, Fitzgerald S, Reed WM. Detection and differentiation of re-emerging fowlpox virus (FWPV) strains carrying integrated reticuloendotheliosis virus (FWPV-REV) by real-time PCR. Vet Microbiol 2008; 127:39-49. [PMID: 17913400 DOI: 10.1016/j.vetmic.2007.08.012] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2007] [Revised: 08/06/2007] [Accepted: 08/10/2007] [Indexed: 10/22/2022]
Abstract
Current strains of fowlpox virus (FWPV) carrying circulating reticuloendotheliosis virus (FWPV-REV) sequence are becoming more pathogenic to poultry. This is evidenced by the fact that vaccination with current available FWPV vaccines provides limited protection against them. To characterize REV insertions in a collection of both older and more recent field isolates, we developed three different types of adjacent oligoprobes and primer sets from specific genomic locations of FWPV and REV: REV-ENV (accession no. K02537, 1382-2260), FWPV-REV integration site (accession no. AF006064, 86-1328), FWPV (accession no. AF198100, 232461-232670), and REV-LTR (accession no. V01204, 305-496). The data indicated that the primers from the REV-ENV region and the TaqMan probes specifically targeted REV-ENV sequences of FWPV-REV strains. Furthermore, the strains were differentiated based on quantitative melting temperature (T(m)) of their amplified products using FRET-based probes. The amplified products were further characterized by sequencing and multiple sequence alignment analysis. The results suggest that integrated REV-ENV sequences are both common and mostly conserved in field isolates. However, the minor variations found within the short-targeted ENV sequence from FWPV-REV strains suggest that these strains could have either undergone periodic point mutational changes or integration with different REV-ENV subtypes.
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Affiliation(s)
- Theodros Tadese
- Department of Pathobiology and Diagnostic Investigation and Diagnostic Center for Population and Animal Health, VMC A-19, Michigan State University, East Lansing, MI 48824, USA.
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29
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Davidson I, Silva RF. Creation of diversity in the animal virus world by inter-species and intra-species recombinations: lessons learned from poultry viruses. Virus Genes 2007; 36:1-9. [DOI: 10.1007/s11262-007-0165-1] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2007] [Accepted: 09/24/2007] [Indexed: 10/22/2022]
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30
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Müller K, Schettler E, Gerlach H, Brunnberg L, Hafez HM, Hattermann K, Johne R, Kollmann R, Krone O, Lierz M, Linke S, Lueschow D, Mankertz A, Müller H, Prusas C, Raue R, Soike D, Speck S, Wolf P, Frölich K. Investigations on the aetiology of pinching off syndrome in four white-tailed sea eagles (Haliaeetus albicilla) from Germany. Avian Pathol 2007; 36:235-43. [PMID: 17497338 DOI: 10.1080/03079450701338748] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
The purpose of this study was to investigate the aetiology of the pinching off syndrome (POS), a generalized feather abnormality affecting free-living nestling of the white-tailed sea eagle (Haliaeetus albicilla) in Europe. For the first time, extensive clinical, haematological, biochemical, virological, bacteriological, nutritional, histopathological, parasitological and electron microscopical examinations were performed on three females and one male suffering from POS. Early and increased cytokeratin formation at the base of regenerating feathers and their follicle was observed in affected birds. Ultrathin sections of the feather papillae revealed an extended stratum transitivum and a compact, thickened keratinized stratum corneum. The transitional cells in POS feathers contained vacuoles often associated with the nucleus. Lipofuscin accumulations in neurons, glial cells and islet cells of the pancreas were found in all examined birds. It was not clear whether there is an association between the occurrence of lipofuscin and POS. No evidence was found to suggest that infectious agents (parasites, bacteria, fungi or viruses), malnutrition or hormonal imbalances are involved in the aetiology of POS in white-tailed sea eagles. It remains unclear whether there is a genetic background of POS.
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Affiliation(s)
- Kerstin Müller
- Small Animal Clinic, Free University of Berlin, Berlin, Germany.
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31
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Prukner-Radovcić E, Lüschow D, Ciglar Grozdanić I, Tisljar M, Mazija H, Vranesić D, Hafez HM. Isolation and Molecular Biological Investigations of Avian Poxviruses from Chickens, a Turkey, and a Pigeon in Croatia. Avian Dis 2006; 50:440-4. [PMID: 17039847 DOI: 10.1637/7506-012006r.1] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
In the last 3 yr, several outbreaks of avian poxviruses (APVs) have been observed in different parts of Croatia. Four strains of APVs, from chickens, a pigeon, and a turkey, were isolated from cutaneous lesions by inoculation onto the chorioallantoic membranes (CAM) of 12-day-old specific-pathogen-free chicken embryos. The resulting proliferative CAM lesions contained eosinophilic cytoplasmic inclusion bodies. The characteristic viral particles of poxvirus were detected in the infected CAM and also in the infected tissues by transmission electron microscopy. Further identification and differentiation of the four various APVs were carried out by the use of a polymerase chain reaction (PCR) combined with restriction enzyme analysis. Using one primer set, which framed a region within the APV 4b core protein gene, it was possible to detect APV-specific DNA from all four tested isolates. PCR results revealed no recognizable differences in size of amplified fragments between the different APVs from chickens, turkey, and pigeon. Restriction enzyme analysis of PCR products using NlaIII showed the same cleavage pattern for turkey and chicken isolates and a different one for the pigeon isolate. Multiplex PCR for direct detection of APV and reticuloendotheliosis virus (REV) was carried out to determine the possible integration of REV in the genome of isolated APVs. The obtained results revealed that REV was present in chicken and turkey strains of poxviruses, whereas the pigeon isolate was negative. It is not known whether the avipoxvirus vaccine strain used in Croatia is contaminated with REV or if the REV is naturally contaminating Croatian field strains of fowl poxvirus. The latter is indicated by the negative REV finding in the pigeon, which was not vaccinated. The results of the present study indicate the reemergence of fowlpox in Croatia, where infections have not been recorded since 1963 and never confirmed etiologically.
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Affiliation(s)
- E Prukner-Radovcić
- Department of Poultry Diseases, Faculty of Veterinary Medicine, University of Zagreb, Heinzelova 55, 10000 Zagreb, Croatia
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32
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Wang J, Meers J, Spradbrow PB, Robinson WF. Evaluation of immune effects of fowlpox vaccine strains and field isolates. Vet Microbiol 2006; 116:106-19. [PMID: 16650660 DOI: 10.1016/j.vetmic.2006.03.012] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2006] [Revised: 03/01/2006] [Accepted: 03/17/2006] [Indexed: 10/24/2022]
Abstract
The immune effects of fowlpox virus (FPV) field isolates and vaccine strains were evaluated in chickens infected at the age of 1 day and 6 weeks. The field isolates and the obsolete vaccine strain (FPV S) contained integrated reticuloendotheliosis virus (REV) provirus, while the current vaccine strain (FPVST) carries only REV LTR sequences. An indirect antibody ELISA was used to measure the FPV-specific antibody response. The non-specific humoral response was evaluated by injection of two T-cell-dependent antigens, sheep red blood cells (SRBC) and bovine serum albumin (BSA). There was no significant difference in the antibody response to FPV between chickens infected with FPV various isolates and strains at either age. In contrast, antibody responses to both SRBC and BSA were significantly lower in 1-day-old chickens inoculated with field isolates and FPV S at 2-3 weeks post-inoculation. Furthermore, cell-mediated immune (CMI) responses measured by in vitro lymphocyte proliferation assay and in vivo using a PHA-P skin test were significantly depressed in chickens inoculated with field isolates and FPV S at the same periods. In addition, thymus and bursal weights were lower in infected chickens. These immunosuppressive effects were not observed in chickens inoculated with the current vaccine strain, FPVST, at any time. The results of this study suggest that virulent field isolates and FPV S have immunosuppressive effects when inoculated into young chickens, which appeared in the first 3 weeks post infection. REV integrated in the FPV field isolates and FPV S may have played a central role in the development of immunosuppression.
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Affiliation(s)
- Jianning Wang
- Investigation & Diagnostic Centre-Wallaceville, Biosecurity New Zealand, Ministry of Agriculture & Forestry, Ward Street, Upper Hutt 6007, New Zealand.
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33
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Cheng WH, Huang YP, Wang CH. Serological and Virological Surveys of Reticuloendotheliosis in Chickens in Taiwan. J Vet Med Sci 2006; 68:1315-20. [PMID: 17213700 DOI: 10.1292/jvms.68.1315] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Reticuloendotheliosis virus (REV) is widespread in the world. No related data has been reported in Taiwan. To determine the REV infection status, antibody determination and virus isolation were performed on chickens in Taiwan. The results revealed that serological flock prevalence for the REV antibody reached 92.8% (39/42) amongst breeders (> 16 weeks old). Two different REV isolates were identified by reverse transcriptase-polymerase chain reaction, electron microscopic, immunofluorescent, and western blot assays after isolation. One of these viruses was isolated from a broiler breeder farm and the other was isolated from a Taiwan Country Chicken farm. Despite their different origins, the percent identity of the nucleotide sequences of the env gene of these two isolates was 99.7%. These two strains were similar to the FPV-UI-REV strain, featuring 99.7% and 99.8% percent identity. Indeed, REV infection would appear to be quite common amongst chickens.
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Affiliation(s)
- Wan-Hsin Cheng
- Department of Veterinary Medicine, National Taiwan University, Taipei, Taiwan
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Kim TJ, Schnitzlein WM, McAloose D, Pessier AP, Tripathy DN. Characterization of an avianpox virus isolated from an Andean condor (Vultur gryphus). Vet Microbiol 2003; 96:237-46. [PMID: 14559171 DOI: 10.1016/j.vetmic.2003.08.003] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A novel pox virus, condorpox virus (CPV) isolated from the spleen of an Andean condor (Vultur gryphus) by inoculation of chorioallantoic membranes (CAM) of specific pathogen free (SPF) chicken embryos was compared biologically, antigenically and genetically with fowlpox virus (FPV), the type species of the genus Avipoxvirus. Susceptible chickens inoculated with CPV developed only mild localized lesions but were not protected against subsequent challenge with FPV. Based on Western blotting, in addition to the presence of cross-reacting antigens, distinct differences in antigenic profiles of CPV and FPV were observed. Sequence analysis of a 4.5 kb HindIII fragment of CPV genomic DNA revealed the presence of eight co-linear genes corresponding to FPV open reading frame (ORF)193-198, 201 and 203. Interestingly, reticuloendotheliosis virus (REV) sequences present in the genome of all FPV were absent in CPV. Although, the results of a phylogenic analysis suggested that CPV is a member of the genus Avipoxvirus, its unique antigenic, biologic and genetic characteristics distinguish it from FPV to be considered as a new member of this genus.
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Affiliation(s)
- Tae-Joong Kim
- Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Illinois, 2001 S. Lincoln Avenue, 61802, Urbana, IL, USA
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Tadese T, Reed WM. Detection of specific reticuloendotheliosis virus sequence and protein from REV-integrated fowlpox virus strains. J Virol Methods 2003; 110:99-104. [PMID: 12757926 DOI: 10.1016/s0166-0934(03)00106-x] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The detection is described of reticuloendotheliosis virus (REV) protein in tissue culture of chicken embryonated cells (CEFs) infected with field isolates of fowl poxvirus (FPV). By the polymerase chain reaction (PCR), five out of the six field isolates, but two out of the seven vaccine strains of FPV, were found to have had a 291 bp repeat sequence of REV-LTR integrated in their genomic DNA. An immunofluorescence (IF) method was employed using a monoclonal antibody (MAb) known to specify strain common envelope proteins for REV and allowed to detect the presence of a specific REV protein. The IF results indicate the localization of REV proteins in boundaries defined precisely within cells infected with these field strains of FPV carrying REV (FPV-REV). Furthermore, by immunoblotting (IB) using a chemiluminescent detection kit, the REV protein reacted specifically with the MAb and had a relative molecular mass (RMM) of 62 kDa. The data have the potential to advance substantially the current understanding of the integrated REV in FPV strains; and the identification of a unique protein associated with variant forms of FPV will also offer great potential for identification of novel vaccine candidates for use in poultry against variant forms of FPV.
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Affiliation(s)
- Theodros Tadese
- Department of Pathobiology and Diagnostic Investigation, Diagnostic Center for Population and Animal Health, Michigan State University, A510 East Fee Hall, East Lansing, MI 48824, USA.
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Singh P, Schnitzlein WM, Tripathy DN. Reticuloendotheliosis virus sequences within the genomes of field strains of fowlpox virus display variability. J Virol 2003; 77:5855-62. [PMID: 12719579 PMCID: PMC154015 DOI: 10.1128/jvi.77.10.5855-5862.2003] [Citation(s) in RCA: 74] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Nine field strains of fowlpox virus (FPV) isolated during a 24-year span from geographically diverse outbreaks of fowlpox in the United States were screened for the presence of reticuloendotheliosis virus (REV) sequences in their genomes by PCR. Each isolate appeared to be heterogeneous in that either a nearly intact provirus or just a 248- or 508-nucleotide fusion of portions of the integrated REV 5' and 3' long terminal repeats (LTRs) was exclusively present at the same genomic site. In contrast, four fowlpox vaccines of FPV origin and three originating from pigeonpox virus were genetically homogeneous in having retained only the 248-bp LTR fusion, whereas two other FPV-based vaccines had only the larger one. These remnants of integrated REV presumably arose during homologous recombination at one of the two regions common to both LTRs or during retroviral excision from the FPV genome. Loss of the provirus appeared to be a natural event because the tripartite population could be detected in a field sample (tracheal lesion). Moreover, the provirus was also readily deleted during propagation of FPV in cultured cells, as evidenced by the detection of truncated LTRs after one passage of a plaque-purified FPV recombinant having a "genetically marked" provirus. However, the deletion mutants did not appear to have a substantial replicative advantage in vitro because even after 55 serial passages the original recombinant FPV was still prevalent. As to the in vivo environment, retention of the REV provirus may confer some benefit to FPV for infection of poultry previously vaccinated against fowlpox.
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Affiliation(s)
- Pratik Singh
- Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Illinois at Urbana-Champaign, Urbana, Illinois 61802, USA
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García M, Narang N, Reed WM, Fadly AM. Molecular characterization of reticuloendotheliosis virus insertions in the genome of field and vaccine strains of fowl poxvirus. Avian Dis 2003; 47:343-54. [PMID: 12887193 DOI: 10.1637/0005-2086(2003)047[0343:mcorvi]2.0.co;2] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Evidence of the widespread occurrence of reticuloendotheliosis virus (REV) sequence insertions in fowl poxvirus (FPV) genome of field isolates and vaccine strains has increased in recent years. However, only those strains carrying a near intact REV provirus are more likely to cause problems in the field. Detection of the intact provirus or REV protein expression from FPV stocks has proven to be technically difficult. The objective of the present study was to evaluate current and newly developed REV and FPV polymerase chain reaction (PCR) assays to detect the presence of REV provirus in FPV samples. The second objective was to characterize REV insertions among recent "variant" FPV field isolates and vaccine strains. With REV, FPV, and heterologous REV-FPV primers, five FPV field isolates and four commercial vaccines were analyzed by PCR and nucleotide sequence analysis. Intact and truncated REV 5' long terminal repeat (LTR) sequences were detected in all FPV field isolates and vaccine strains, indicating heterogeneous REV genome populations. However only truncated 3' LTR and envelope sequences were detected among field isolates and in one vaccine strain. Amplifications of the REV envelope and 3' LTR provided strong evidence to indicate that these isolates carry a near intact REV genome. Three of the four FPV vaccine strains analyzed carried a solo complete or truncated 5' LTR sequence, indicating that intact REV provirus was not present. Comparison of PCR assays indicated that assays amplifying REV envelope and REV 3' LTR sequences provided a more accurate assessment of REV provirus than PCR assays that amplify the REV 5' LTR region. Therefore, to differentiate FPV strains that carry intact REV provirus from those that carry solo 5' LTR sequences, positive PCR results with primers that amplify the 5' LTR should be confirmed with more specific PCR assays, such as the envelope, or the REV 3' LTR PCR.
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Affiliation(s)
- Maricarmen García
- Department of Avian Medicine, College of Veterinary Medicine, University of Georgia, Athens, GA 30606, USA
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Borenshtain R, Witter RL, Davidson I. Persistence of chicken herpesvirus and retroviral chimeric molecules upon in vivo passage. Avian Dis 2003; 47:296-308. [PMID: 12887189 DOI: 10.1637/0005-2086(2003)047[0296:pochar]2.0.co;2] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Mareks disease virus (MDV), a herpesvirus, and avian leucosis virus subgroup J (ALV-J), a retrovirus, were used for experimental coinfection of chickens. Chimeric molecules having sequences of both viruses were detected by the hotspot-combined polymerase chain reaction (HS-cPCR) system. The detection of chimeric molecules provided evidence for avian retroviral inserts in the herpesvirus genome. The persistence of chimeric molecules on in vivo passage served to indicate the infectivity of the recombinant virus. The evaluation of formation and persistence of the chimeric molecules was performed in two trials involving three in vivo passages. The chimeric molecules were identified according to the primer sets, their product length, and pattern. The persistence of chimeric molecules on in vivo passages served as an indication of their ability to replicate in and infect chickens. In the first experimental passage, MDV and ALV-J prototype strains, MD11 and HC-1, were intraperitoneally (i.p.) injected into 1-day-old chicks. The second trial included two passages. Passage II chicks were injected i.p. and passage III chickens were in contact with the chickens of passage II. For passage II, enriched white blood cells from blood samples of chickens from the first trial that had chimeric molecules were injected i.p. into 1-day-old chicks. For passage III, uninfected chicks were included together with the infected chicks. Synthesis evidence for the various species of chimeric molecules was assessed in the tissues of birds of the second trial. DNA was extracted from blood and feathers and analyzed by the hotspot-combined PCR and by pulsed field gel electrophoresis. To overcome the limits of detection, three amplification assays followed by hybridization of the products to specific viral probes were conducted. A variety of chimeric molecules were detected in low concentrations. Five species of chimeric molecules were characterized in blood, tumors, and feathers. Chimeric molecules were detected in 18 of 36 dually infected birds from the first trial and in 14 of 21 dually infected birds from the second trial. The findings show that, in four out of seven groups of the second trial, the chimeric molecule species persisted on passage.
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Affiliation(s)
- R Borenshtain
- Division of Avian Diseases, Kimron Veterinary Institute, Bet Dagan, P.O. Box 12, Israel 50250
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Fallavena LCB, Canal CW, Salle CTP, Moraes HLS, Rocha SLS, Pereira RA, da Silva AB. Presence of avipoxvirus DNA in avian dermal squamous cell carcinoma. Avian Pathol 2002; 31:241-6. [PMID: 12396347 DOI: 10.1080/03079450220136558] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
Abstract
Dermal squamous cell carcinoma (DSCC; avian keratoacanthoma) is a neoplastic skin lesion of broiler chickens of unknown aetiology. In previous studies, the possibility of the involvement of pox viruses in the cause of DSCC was considered. In this work, a sensitive and specific nested polymerase chain reaction (PCR) protocol was developed that could amplify a 419 base pair DNA fragment of fowlpox virus with a detection limit of less than one infectious unit. Fowlpox virus DNA was always detected in skin samples with fowlpox lesions while it was not detected in samples of unrelated diseases such as cowpox, Marek's disease or infectious laryngotracheitis. Some macroscopically normal skin samples from vaccinated and non-vaccinated birds also produced PCR-positive results, corroborating previous studies on the possibility that a latent or chronic form of fowlpox occurs. Fowlpox virus DNA was consistently detected from DSCC skin lesions, and this finding is discussed.
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Affiliation(s)
- Luiz C B Fallavena
- Centro de Diagnóstico e Pesquisa em Patologia Aviária, Faculdade de Veterinária, Universidade Federal do Rio Grande do Sul, Av. Bento Gonçalves 8824, Porto Alegre, CEP 91540-000, Rio Grande do Sul, Brazil.
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