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Adedeji AJ, Shittu I, Akanbi OB, Asala OO, Adole JA, Okewole PA, Ijale GO, Kabantiyok D, Idoko F, Shallmizhili JJ, Abdu PA, Pewan SB. First report of co-infections of Marek's disease virus and chicken infectious anaemia virus in poultry flocks in Nigeria. Vet Anim Sci 2024; 23:100339. [PMID: 38406258 PMCID: PMC10884768 DOI: 10.1016/j.vas.2024.100339] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/27/2024] Open
Abstract
Marek's disease (MD) and chicken infectious anaemia (CIA) are viral immunosuppressive diseases of poultry caused by the MD virus (MDV) and CIA virus (CIAV) respectively. Despite vaccination against MD, the incidence of the disease in vaccinated poultry flocks in Nigeria persists. However, underlying factors like co-infection with CIAV have not been investigated in the country. This study was designed to investigate possible co-infections of MDV and CIAV in poultry flocks in Nigeria. In 2016, tumorous tissue samples were collected from suspected cases of MD at necropsy in Jos, Plateau State, Nigeria. The samples collected were fixed in formalin for histopathological examination, genomic DNA was extracted from a second part and analysed by polymerase chain reaction (PCR), targeting the meq and VP1 genes of the MDV and CIAV, respectively. The histology results revealed that the cutaneous and proventricular lymphomas were characterized by large numbers of mononuclear cellular infiltrates admixed with heterophils. The PCR results revealed that MDV was detected in 66.7% (16/24), CIAV in 45.8% (11/24), and co-infections of MDV and CIAV were detected in 45.8% (11/24) of the samples analysed. In addition, co-infections of MD and CIA were recorded in 100% (6/6) and 27.7% (5/18) of broilers and layer/pullet' samples respectively. Phylogenetic analysis of the meq gene sequences revealed that the Nigerian MDV clusters with very virulent MDV from Egypt and Italy. While, CIAV sequences were genotype II and genotype III and clustered with CIAVs from Cameroon and China. This is the first report of co-infections of MD and CIA in Nigeria.
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Affiliation(s)
| | | | - Olatunde B. Akanbi
- Department of Veterinary Pathology, Faculty of Veterinary Medicine, University of Ilorin, Nigeria
| | | | | | | | - Gabriel O. Ijale
- Federal Ministry of Agriculture and Rural Development, Abuja, Nigeria
| | | | - Felix Idoko
- National Veterinary Research Institute Vom, Nigeria
| | | | - Paul A. Abdu
- Faculty of Veterinary Medicine, Ahmadu Bello University Zaria, Nigeria
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Di Francesco A, Quaglia G, Salvatore D, Sakhria S, Catelli E, Bessoussa G, Kaboudi K, Ben Chehida N, Lupini C. Occurrence of Chicken Infectious Anemia Virus in Industrial and Backyard Tunisian Broilers: Preliminary Results. Animals (Basel) 2021; 12:ani12010062. [PMID: 35011168 PMCID: PMC8749614 DOI: 10.3390/ani12010062] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2021] [Revised: 12/10/2021] [Accepted: 12/25/2021] [Indexed: 02/04/2023] Open
Abstract
Chicken infectious anemia virus (CIAV) is an economically important and widely distributed immunosuppressive agent in chickens. This study performed an epidemiological investigation on CIAV circulation in 195 Tunisian broilers, belonging to 13 lots from five industrial farms and in one rural farm. Fifteen animals were detected positive by a VP1 nested PCR. The amplicons were molecularly characterised by complete genome sequencing. All positive samples obtained in this study were from the rural farm, whereas the industrial farms sampled were negative. Nucleotide and amino acid sequence analyses showed a high degree of similarity among the sequences obtained, suggesting the circulation of a single CIAV strain in the positive lot. Phylogenetic analysis based on the CIAV VP1 nucleotide sequence and/or the complete genome showed that the sequences obtained in this study clustered with CIAV strains previously detected in Tunisia, Italy and Egypt, belonging to genogroup II. Our results highlight the need for constant CIAV surveillance in backyard chicken production.
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Affiliation(s)
- Antonietta Di Francesco
- Department of Veterinary Medical Sciences, University of Bologna, Ozzano dell’Emilia, 40064 Bologna, Italy; (G.Q.); (D.S.); (E.C.); (C.L.)
- Correspondence:
| | - Giulia Quaglia
- Department of Veterinary Medical Sciences, University of Bologna, Ozzano dell’Emilia, 40064 Bologna, Italy; (G.Q.); (D.S.); (E.C.); (C.L.)
| | - Daniela Salvatore
- Department of Veterinary Medical Sciences, University of Bologna, Ozzano dell’Emilia, 40064 Bologna, Italy; (G.Q.); (D.S.); (E.C.); (C.L.)
| | - Sonia Sakhria
- Institute of Veterinary Research of Tunisia, University of Tunis El Manar, Tunis 1006, Tunisia; (S.S.); (N.B.C.)
| | - Elena Catelli
- Department of Veterinary Medical Sciences, University of Bologna, Ozzano dell’Emilia, 40064 Bologna, Italy; (G.Q.); (D.S.); (E.C.); (C.L.)
| | - Ghaith Bessoussa
- Commissariat Régional au Développement Agricole, Ben Arous 2063, Tunisia;
| | - Khaled Kaboudi
- National School of Veterinary Medicine of Sidi Thabet, University of Manouba, Sidi Thabet 2020, Tunisia;
| | - Noureddine Ben Chehida
- Institute of Veterinary Research of Tunisia, University of Tunis El Manar, Tunis 1006, Tunisia; (S.S.); (N.B.C.)
| | - Caterina Lupini
- Department of Veterinary Medical Sciences, University of Bologna, Ozzano dell’Emilia, 40064 Bologna, Italy; (G.Q.); (D.S.); (E.C.); (C.L.)
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Sajewicz-Krukowska J, Jastrzębski JP, Grzybek M, Domańska-Blicharz K, Tarasiuk K, Marzec-Kotarska B. Transcriptome Sequencing of the Spleen Reveals Antiviral Response Genes in Chickens Infected with CAstV. Viruses 2021; 13:2374. [PMID: 34960643 PMCID: PMC8708055 DOI: 10.3390/v13122374] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2021] [Revised: 11/19/2021] [Accepted: 11/22/2021] [Indexed: 11/16/2022] Open
Abstract
Astrovirus infections pose a significant problem in the poultry industry, leading to multiple adverse effects such as a decreased egg production, breeding disorders, poor weight gain, and even increased mortality. The commonly observed chicken astrovirus (CAstV) was recently reported to be responsible for the "white chicks syndrome" associated with an increased embryo/chick mortality. CAstV-mediated pathogenesis in chickens occurs due to complex interactions between the infectious pathogen and the immune system. Many aspects of CAstV-chicken interactions remain unclear, and there is no information available regarding possible changes in gene expression in the chicken spleen in response to CAstV infection. We aim to investigate changes in gene expression triggered by CAstV infection. Ten 21-day-old SPF White Leghorn chickens were divided into two groups of five birds each. One group was inoculated with CAstV, and the other used as the negative control. At 4 days post infection, spleen samples were collected and immediately frozen at -70 °C for RNA isolation. We analyzed the isolated RNA, using RNA-seq to generate transcriptional profiles of the chickens' spleens and identify differentially expressed genes (DEGs). The RNA-seq findings were verified by quantitative reverse-transcription PCR (qRT-PCR). A total of 31,959 genes was identified in response to CAstV infection. Eventually, 45 DEGs (p-value < 0.05; log2 fold change > 1) were recognized in the spleen after CAstV infection (26 upregulated DEGs and 19 downregulated DEGs). qRT-PCR performed on four genes (IFIT5, OASL, RASD1, and DDX60) confirmed the RNA-seq results. The most differentially expressed genes encode putative IFN-induced CAstV restriction factors. Most DEGs were associated with the RIG-I-like signaling pathway or more generally with an innate antiviral response (upregulated: BLEC3, CMPK2, IFIT5, OASL, DDX60, and IFI6; downregulated: SPIK5, SELENOP, HSPA2, TMEM158, RASD1, and YWHAB). The study provides a global analysis of host transcriptional changes that occur during CAstV infection in vivo and proves that, in the spleen, CAstV infection in chickens predominantly affects the cell cycle and immune signaling.
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Affiliation(s)
- Joanna Sajewicz-Krukowska
- Department of Poultry Diseases, National Veterinary Research Institute, 24-100 Puławy, Poland; (K.D.-B.); (K.T.)
| | - Jan Paweł Jastrzębski
- Department of Plant Physiology, Genetics and Biotechnology, Faculty of Biology and Biotechnology, University of Warmia and Mazury in Olsztyn, 10-719 Olsztyn, Poland;
| | - Maciej Grzybek
- Department of Tropical Parasitology, Institute of Maritime and Tropical Medicine, Medical University of Gdansk, 81-519 Gdynia, Poland;
| | - Katarzyna Domańska-Blicharz
- Department of Poultry Diseases, National Veterinary Research Institute, 24-100 Puławy, Poland; (K.D.-B.); (K.T.)
| | - Karolina Tarasiuk
- Department of Poultry Diseases, National Veterinary Research Institute, 24-100 Puławy, Poland; (K.D.-B.); (K.T.)
| | - Barbara Marzec-Kotarska
- Department of Clinical Pathomorphology, The Medical University of Lublin, 20-090 Lublin, Poland;
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Campbell Z, Coleman P, Guest A, Kushwaha P, Ramuthivheli T, Osebe T, Perry B, Salt J. Prioritizing smallholder animal health needs in East Africa, West Africa, and South Asia using three approaches: Literature review, expert workshops, and practitioner surveys. Prev Vet Med 2021; 189:105279. [PMID: 33581421 PMCID: PMC8024747 DOI: 10.1016/j.prevetmed.2021.105279] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Revised: 12/18/2020] [Accepted: 01/18/2021] [Indexed: 12/15/2022]
Abstract
Managing the health needs of livestock contributes to reducing poverty and improving the livelihoods of smallholder and pastoralist livestock keepers globally. Animal health practitioners, producers, policymakers, and researchers all must prioritize how to mobilize limited resources. This study employed three approaches to prioritize animal health needs in East and West Africa and South Asia to identify diseases and syndromes that impact livestock keepers. The approaches were a) systematic literature review, b) a series of expert workshops, and c) a practitioner survey of veterinarians and para-veterinary professionals. The top constraints that emerged from all three approaches include endo/ ectoparasites, foot and mouth disease, brucellosis, peste des petits ruminants, Newcastle disease, and avian influenza. Expert workshops additionally identified contagious caprine pleuropneumonia, contagious bovine pleuropneumonia, mastitis, and reproductive disorders as constraints not emphasized in the literature review. Practitioner survey results additionally identified nutrition as a constraint for smallholder dairy and pastoralist small ruminant production. Experts attending the workshops agreed most constraints can be managed using existing veterinary technologies and best husbandry practices, which supports a shift away from focusing on individual diseases and new technologies towards addressing systemic challenges that limit access to veterinary services and inputs. Few research studies focused on incidence/ prevalence of disease and impact, suggesting better incorporation of socio-economic impact measures in future research would better represent the interests of livestock keepers.
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Affiliation(s)
- Zoë Campbell
- International Livestock Research Institute (ILRI), P.O. Box 30709, Nairobi, 00100, Kenya.
| | - Paul Coleman
- H20 Venture Partners, 33-35 George Street, Oxford, OX1 2AY, United Kingdom
| | - Andrea Guest
- H20 Venture Partners, 33-35 George Street, Oxford, OX1 2AY, United Kingdom
| | - Peetambar Kushwaha
- GALVmed Asia Office, Unit 118 & 120 B, Splendor Forum, Plot No 3, Jasola District Centre, Jasola, New Delhi, 110025, India
| | - Thembinkosi Ramuthivheli
- GALVmed Africa Office, International Livestock Research Institute (ILRI), Swing One, Naivasha Road, Nairobi, Kenya
| | - Tom Osebe
- GALVmed Africa Office, International Livestock Research Institute (ILRI), Swing One, Naivasha Road, Nairobi, Kenya
| | - Brian Perry
- Nuffield College of Clinical Medicine, University of Oxford, United Kingdom; College of Medicine and Veterinary Medicine, University of Edinburgh, Arthurstone House, Meigle, Blairgowrie, PH12 8QW, Scotland, United Kingdom
| | - Jeremy Salt
- GALVmed UK Office, Doherty Building, Pentlands Science Park, Bush Loan, Penicuik Edinburgh, EH26 0PZ, Scotland, United Kingdom
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Huynh LTM, Nguyen GV, Do LD, Dao TD, Le TV, Vu NT, Cao PTB. Chicken infectious anaemia virus infections in chickens in northern Vietnam: epidemiological features and genetic characterization of the causative agent. Avian Pathol 2019; 49:5-14. [PMID: 31259607 DOI: 10.1080/03079457.2019.1637821] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Since the first report of chicken infectious anaemia virus (CIAV) in Vietnam in 2013, there have not been many studies focused on the detection of CIAV or the molecular characteristics of the virus. This study attempted to investigate the presence of CIAV in northern Vietnam by molecular-based methods. Regarding the spatial distribution of CIAV, the PCR-based results showed that CIAV was detected in 47 out of 64 farms (73.4%) and in all 10 investigated provinces. Of the 119 samples assayed by PCR, 74 (62.2%) tested positive for CIAV DNA. By arranging the samples into different categories, it was found that CIAV was detected at high rates (above 50%) based on all 4 evaluated criteria as follows: production type of chicken, housing system, flock size and age group. Different housing systems were significantly associated with the detection rates of CIAV (P = 0.003). By genetic analyses, all of the Vietnamese CIAVs were found to (i) lack substitutions related to attenuation substitutions, (ii) group separately from vaccine-like CIAVs and (iii) belong to genogroups G2 and G3 of CIAV. Because of the wide distribution of CIAV and because the virus was confirmed not to be vaccine-like viruses, it is suggested that further studies be conducted on the clinical form of chicken infectious anaemia, as well as the immunosuppressive effect of CIAV on chickens in Vietnam.RESEARCH HIGHLIGHTS Wide distribution of chicken infectious anaemia virus (CIAV) in northern Vietnam.Vietnamese CIAVs belong to genogroups G2 and G3 of CIAV.
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Affiliation(s)
- Le Thi My Huynh
- Department of Veterinary Microbiology and Infectious Diseases, Faculty of Veterinary Medicine, Vietnam National University of Agriculture, Hanoi, Vietnam
| | - Giap Van Nguyen
- Department of Veterinary Microbiology and Infectious Diseases, Faculty of Veterinary Medicine, Vietnam National University of Agriculture, Hanoi, Vietnam
| | - Luc Duc Do
- Department of Animal Breeding and Genetics, Faculty of Animal Science, Vietnam National University of Agriculture, Hanoi, Vietnam
| | - Trang Doan Dao
- Center of Applied Research and Livestock Genetic Conservation, National Institute of Animal Sciences, Hanoi, Vietnam
| | - Truong Van Le
- Department of Veterinary Microbiology and Infectious Diseases, Faculty of Veterinary Medicine, Vietnam National University of Agriculture, Hanoi, Vietnam
| | - Ngoc Thi Vu
- Department of Veterinary Microbiology and Infectious Diseases, Faculty of Veterinary Medicine, Vietnam National University of Agriculture, Hanoi, Vietnam
| | - Phuong Thi Bich Cao
- Department of Veterinary Microbiology and Infectious Diseases, Faculty of Veterinary Medicine, Vietnam National University of Agriculture, Hanoi, Vietnam
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Rani S, Kumar S. Evaluation of infectious bursal disease virus stability at different conditions of temperature and pH. Biologicals 2015; 43:515-8. [PMID: 26265229 DOI: 10.1016/j.biologicals.2015.07.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2015] [Revised: 06/23/2015] [Accepted: 07/18/2015] [Indexed: 10/23/2022] Open
Abstract
Infectious bursal disease (IBD) is one of the highly pathogenic viral diseases of poultry. The disease poses a serious threat to the economy of many developing countries where agriculture serves as the primary source of national income. Infectious bursal disease virus (IBDV) belongs to the family Birnaviridae. The IBDV is well characterized to cause immunosuppression in poultry. The live attenuated vaccine is the only way to protect the chickens from IBDV infection. The ineffectiveness of vaccine is one of the major causes of IBDV outbreaks in field condition. In the present study, we discuss briefly about the biology of IBDV genome and its proteins under different conditions of temperature and pH in order to evaluate its infectivity under adverse physical conditions. Our results indicate that the IBDV is non-infective above 42 °C and unstable above 72 °C. However, the change in pH does not significantly contribute to the IBDV stability. The study will be useful in estimating an optimum storage condition for IBDV vaccines without causing any deterioration in its viability and effectiveness.
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Affiliation(s)
- Surabhi Rani
- Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati, Guwahati, Assam 781039, India
| | - Sachin Kumar
- Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati, Guwahati, Assam 781039, India.
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Novel Gyroviruses, including Chicken Anaemia Virus, in Clinical and Chicken Samples from South Africa. Adv Virol 2014; 2014:321284. [PMID: 24876841 PMCID: PMC4022007 DOI: 10.1155/2014/321284] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2013] [Accepted: 03/17/2014] [Indexed: 11/18/2022] Open
Abstract
Introduction. Chicken anaemia virus, CAV, was until recently the only member of the Gyrovirus genus. 6 novel gyroviruses, AGV2, HGyV1, and GyV3-6, have since been discovered in human and chicken samples. Methods. PCR amplification of the VP2 gene was used to detect AGV2/HGyV1, GyV3, and CAV in a range of clinical samples including stool, respiratory, CSF, and HIV-positive plasma. Screening of fresh local chicken meat was also performed. Results. AGV2/HGyV1 or GyV3 was detected in stools from healthy children (17/49, 34.7%) and patients with diarrhoea (22/149, 14.8%). 1.2% (3/246) nasopharyngeal respiratory samples were positive. No AGV2/HGyV1 or GyV3 was detected in nasal swabs from wheezing patients, in CSF from patients with meningitis, and in HIVpositive plasma. CAV was found in 51% (25/49) of stools from healthy children and 16% (24/149) in diarrhoea samples. Screening of 28 chicken samples showed a higher prevalence of gyrovirus (20/28, 71%) compared to CAV (1/28, 3.6%). Phylogenetic analysis of the CAV VP1 gene showed South African sequences clustering with Brazilian isolates from genotypes D2 and A2. Conclusion. Novel gyroviruses, including CAV, are present in the South African population with diarrhoea and respiratory illness as well as in healthy children. Their presence suggests an origin from chicken meat consumption.
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Kye SJ, Kim JY, Seul HJ, Kim S, Kim SE, Lee HS, Sorn S, Choi KS. Phylogenetic analysis and genetic characterization of chicken anemia virus isolates from Cambodia. Poult Sci 2013; 92:2681-6. [PMID: 24046415 DOI: 10.3382/ps.2013-03204] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Three chicken anemia viruses (CAV) were detected by PCR during screening of field samples from village chickens collected in Cambodia in 2011/2012. Nearly full-length VP1 viral structural protein genes (nt 1-1,293) from the 3 CAV were sequenced and characterized. Phylogenetic analysis revealed that all 3 of the Cambodian CAV were clustered with CAV strains belonging to genotype II and were most closely related to CAV strains from Guangdong province, China. On the amino acid level, major substitutions were observed at 12 residues in the VP1 protein (positions 22, 75, 97, 125, 139, 144, 254, 287, 290, 370, 376, and 413) when compared with published reference CAV strains. In motifs associated with virulence, all Cambodian CAV had virulence-associated motifs composed of 75I, 89T, 125I, 139Q, 141Q, 144Q, and 394Q, which are commonly found in highly virulent genotype II viruses and some genotype III viruses. This is the first report of CAV isolated from village chickens in Southeast Asia as well as Cambodia.
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Affiliation(s)
- Soo-Jeong Kye
- Avian Diseases Division, Animal and Plant Quarantine Agency, Gyeonggi 430-757, Republic of Korea; and
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Epidemiology of chicken anemia virus in Central African Republic and Cameroon. Virol J 2012; 9:189. [PMID: 22958546 PMCID: PMC3495741 DOI: 10.1186/1743-422x-9-189] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2011] [Accepted: 08/14/2012] [Indexed: 11/24/2022] Open
Abstract
Background Although chicken anemia virus (CAV) has been detected on all continents, little is known about this virus in sub-Saharan Africa. This study aimed to detect and characterize CAV for the first time in Central African Republic and in Cameroon. Results An overall flock seroprevalence of 36.7% was found in Central African Republic during the 2008–2010 period. Virus prevalences were 34.2% (2008), 14.3% (2009) and 10.4% (2010) in Central African Republic and 39% (2007) and 34.9% (2009) in Cameroon. CAV DNA was found in cloacal swabs of 76.9% of seropositive chickens, suggesting that these animals excreted the virus despite antibodies. On the basis of VP1 sequences, most of the strains in Central African Republic and Cameroon belonged to 9 distinct phylogenetic clusters at the nucleotide level and were not intermixed with strains from other continent. Several cases of mixed infections in flocks and individual chickens were identified. Conclusions Our results suggest multiple introductions of CAV in each country that later spread and diverged locally. Mixed genotype infections together with the observation of CAV DNA in cloacal samples despite antibodies suggest a suboptimal protection by antibodies or virus persistence.
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van Santen VL, Toro H, Hoerr FJ. Biological Characteristics of Chicken Anemia Virus Regenerated from Clinical Specimen by PCR. Avian Dis 2007; 51:66-77. [PMID: 17461269 DOI: 10.1637/0005-2086(2007)051[0066:bcocav]2.0.co;2] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Our previous genetic characterization of chicken anemia virus (CAV) in commercial broiler chickens in Alabama revealed a previously undetected polymorphism: a glutamine codon at VP1 position 22, in 7 of the 14 sequences. The novel glutamine codon was always found in association with a VP1 "hypervariable region" identical to CAV field isolates that replicate poorly in culture. The complete genome of CAV73, representative of the sequences with the novel polymorphism, was generated from cloned polymerase chain reaction (PCR) fragments amplified directly from naturally infected tissues. CAV73 had been detected in 31-day-old broilers submitted for examination for reasons unrelated to anemia. After electroporation of the cloned genomes into MDCC-CU147 lymphoblastoid cells, the regenerated CAV caused the culture to fail within 9 days, and the medium contained 5 X 10(6) TCID50 CAV/ml. Use of MDCC-CU147 cells was essential, as identical electroporation of MDCC-MSB1 cells failed to generate CAV able to destroy the culture within 8 wk. Regenerated CAV73 produced anemia and severe lymphocytic depletion of the thymus when inoculated into susceptible 3-day-old chickens and was reisolated from these chickens. Furthermore, it replicated in low- and high-passage MDCC-MSB1 cells similarly to a low-passage CAV field isolate that contains a different VP 1 "hypervariable region." The regeneration of CAV from PCR products directly from naturally infected carcasses, as performed in this study, provides a tool for the evaluation of distinct genetic polymorphisms that may be detected in specimens where infective virions are no longer available. Our results also provide some insight into the differential susceptibility of cell lines for low-passage CAV field isolates.
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Affiliation(s)
- Vicky L van Santen
- Department of Pathobiology, College of Veterinary Medicine, Auburn University, Auburn, AL 36849-5519, USA
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