title: Molecular characterization and phylogenetic analysis of infectious bursal disease viruses isolated from chicken in South China in 2011.
abstract: Infectious bursal disease virus (IBDV) is a double-stranded RNA virus that causes immunosuppressive disease in young chickens. Thousands of cases of IBDV infection are reported each year in South China, and these infections can result in considerable economic losses to the poultry industry. To monitor variations of the virus during the outbreaks, 30 IBDVs were identified from vaccinated chicken flocks from nine provinces in South China in 2011. VP2 fragments from different virus strains were sequenced and analyzed by comparison with the published sequences of IBDV strains from China and around the world. Phylogenetic analysis of hypervariable regions of the VP2 (vVP2) gene showed that 29 of the isolates were very virulent (vv) IBDVs, and were closely related to vvIBDV strains from Europe and Asia. Alignment analysis of the deduced amino acid (aa) sequences of vVP2 showed the 29 vv isolates had high uniformity, indicated low variability and slow evolution of the virus. The non-vvIBDV isolate JX2-11 was associated with higher than expected mortality, and had high deduced aa sequence similarity (99.2 %) with the attenuated vaccine strain B87 (BJ). The present study has demonstrated the continued circulation of IBDV strains in South China, and emphasizes the importance of reinforcing IBDV surveillance.
authors.affiliation: College of Animal Science, South China Agricultural University, Guangzhou, 510642, China.
authors.forename: Di
authors.initials: D
authors.lastname: Liu
authors.forename: Xiang-Bin
authors.initials: XB
authors.lastname: Zhang
authors.forename: Zhuan-Qiang
authors.initials: ZQ
authors.lastname: Yan
authors.forename: Feng
authors.initials: F
authors.lastname: Chen
authors.forename: Jun
authors.initials: J
authors.lastname: Ji
authors.forename: Jian-Ping
authors.initials: JP
authors.lastname: Qin
authors.forename: Hai-Yan
authors.initials: HY
authors.lastname: Li
authors.forename: Jun-Peng
authors.initials: JP
authors.lastname: Lu
authors.forename: Yu
authors.initials: Y
authors.lastname: Xue
authors.forename: Jia-Jia
authors.initials: JJ
authors.lastname: Liu
authors.forename: Qing-Mei
authors.initials: QM
authors.lastname: Xie
authors.forename: Jing-Yun
authors.initials: JY
authors.lastname: Ma
authors.forename: Chun-Yi
authors.initials: CY
authors.lastname: Xue
authors.forename: Ying-Zuo
authors.initials: YZ
authors.lastname: Bee
mesh_terms: D019943:Amino Acid Substitution; D000818:Animals; D018175:Birnaviridae Infections / Q000453:epidemiology / Q000662:veterinary* / Q000821:virology; D002645:Chickens; D002681:China / Q000453:epidemiology; D007243:Infectious bursal disease virus / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism; D008969:Molecular Sequence Data; D010802:Phylogeny; D016133:Polymerase Chain Reaction / Q000662:veterinary; D011201:Poultry Diseases / Q000453:epidemiology* / Q000821:virology; D015995:Prevalence; D017422:Sequence Analysis, DNA / Q000662:veterinary; D020539:Sequence Analysis, Protein / Q000662:veterinary; D017386:Sequence Homology, Amino Acid; D015678:Viral Structural Proteins / Q000235:genetics* / Q000378:metabolism
chemical_list: C082513:VP2 protein, infectious bursal disease virus; D015678:Viral Structural Proteins