title: Detection of vaccine-like infectious bursal disease (IBD) virus in IBD vaccine-free chickens in Japan.
abstract: The prevalence of infectious bursal disease virus (IBDV) was studied in chickens, which had not been vaccinated against IBD. Fifty sera and forty-six bursae of Fabricius from chickens showing impaired growth, collected from 7 IBD vaccination-free farms in Japan were used for virus neutralization (VN) tests and RT-PCR for detection of IBDV genome corresponding to the VP2 hypervariable region. Of the fifty sera, 39 sera (78%) from 6 farms were VN antibodies positive. Of the forty-six bursae, 37 bursae (80.4%) from 6 farms were positive in the RT-PCR assay. The sequences of all the RT-PCR products detected in this study were closely related or identical to those of the vaccine strains. These results show that vaccine-like IBDV is prevalent even in IBD vaccine-free chicken farms in Japan.
authors.affiliation: Department of Applied Veterinary Sciences, United Graduate School of Veterinary Sciences, Gifu University, Gifu, Japan.
authors.forename: Min Thein
authors.initials: MT
authors.lastname: Maw
authors.forename: Tsuyoshi
authors.initials: T
authors.lastname: Yamaguchi
authors.forename: Kenji
authors.initials: K
authors.lastname: Ohya
authors.forename: Hideto
authors.initials: H
authors.lastname: Fukushi
mesh_terms: D000818:Animals; D018175:Birnaviridae Infections / Q000175:diagnosis / Q000453:epidemiology / Q000276:immunology / Q000662:veterinary*; D002645:Chickens; D017931:DNA Primers; D007243:Infectious bursal disease virus / Q000235:genetics / Q000302:isolation & purification*; D007564:Japan / Q000453:epidemiology; D011201:Poultry Diseases / Q000175:diagnosis / Q000453:epidemiology / Q000276:immunology / Q000821:virology*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D016036:Seroepidemiologic Studies; D014765:Viral Vaccines
chemical_list: D017931:DNA Primers; D014765:Viral Vaccines