Search results for: Kunitoshi%20Imai
2 Genetic Characteristics of Chicken Anemia Virus Circulating in Northern Vietnam
Authors: Hieu Van Dong, Giang Thi Huong Tran, Giap Van Nguyen, Tung Duy Dao, Vuong Nghia Bui, Le Thi My Huynh, Yohei Takeda, Haruko Ogawa, Kunitoshi Imai
Abstract:
Chicken anemia virus (CAV) has a ubiquitous and worldwide distribution in chicken production. Our group previously reported high seroprevalence of CAV in chickens in northern Vietnam. In the present study, 330 tissue samples collected from commercial and breeder chicken farms in eleven provinces in northern Vietnam were tested for the CAV infection. We found that 157 out of 330 (47.58%) chickens were positive with CAV genes by real-time PCR method. Nine CAV strains obtained from the different location and time were forwarded to the full-length sequence of CAV VP1 gene. Phylogenetic analysis of the Vietnamese CAV vp1 gene indicated that the CAVs circulating in northern Vietnam were divided into three distinct genotypes, II, III, and V, but not clustered with the vaccine strains. Among the three genotypes, genotype III was the major one widely spread in Vietnam, and that included three sub-genotypes, IIIa, IIIb, and IIIc. The Vietnamese CAV strains were closely related to the Chinese, Taiwanese, and USA strains. All the CAV isolates had glutamine at amino acid position 394 in the VP1 gene, suggesting that they might be highly pathogenic strains. One strain was defined to be genotype V, which had not been reported for Vietnamese CAVs. Additional studies are required to further evaluate the pathogenicity of CAV strains circulating in Vietnam.Keywords: chicken anemia virus, genotype, genetic characteristics, Vietnam
Procedia PDF Downloads 1211 Phylogenetic Analyses of Newcastle Disease Virus Isolated from Unvaccinated Chicken Flocks in Kyrgyzstan from 2015 to 2016
Authors: Giang Tran Thi Huong, Hieu Dong Van, Tung Dao Duy, Saadanov Iskender, Isakeev Mairambek, Tsutomu Omatsu, Yukie Katayama, Tetsuya Mizutani, Yuki Ozeki, Yohei Takeda, Haruko Ogawa, Kunitoshi Imai
Abstract:
Newcastle disease virus (NDV) is a contagious viral disease of the poultry industry and other birds throughout the world. At present, very little is known about molecular epidemiological data regarding the causes of ND outbreak in commercial poultry farms in Kyrgyzstan. In the current study, the NDV isolated from the one out of three samples from the unvaccinated flock was confirmed as NDV. Phylogenetic analysis indicated that this NDV strain is clustered in the Class II subgenotype VIId, and closely related to the Chinese NDV isolate. Phylogenetic analyses revealed that the isolated NDV strain has an origin different from the 4 NDV strains previously identified in Kyrgyzstan. According to the mean death time (MDT: 61.1 h) and a multibasic amino acid (aa) sequence at the F0 proteolytic cleavage site (¹¹²R-R-Q-K-R-F¹¹⁷), the NDV isolate was determined as mesogenic strain. Several mutations in the neutralizing epitopes (notably, ³⁴⁷E→K) and the global head were observed in the hemagglutinin-neuraminidase (HN) protein of the current isolate. The present study represents the molecular characterization of the coding gene region of NDV in Kyrgyzstan. Additionally, further study will be investigated on the antigenic characterization using monoclonal antibody.Keywords: Kyrgyzstan, Newcastle disease, genotype, genome characterization
Procedia PDF Downloads 106