title: [Isolation and identification of avian leukosis virus-B from layer chickens infected with avian leukosis virus-J].
abstract: Two strains of Avian leukosis virus subgroup B (ALV-B) were isolated for the first time in China Hy-line White on the cultured DF-1 cells which were inoculated tissue samples from by an ELISA assay, a histopathology examination and a PCR-based diagnosis. The results from the ELISA assay indicated that the positive rate of serum antibodies to ALV-B and ALV-J virus were 16.3% (15/92) and 13% (12/92), respectively. The histopathological examination indicated that two types of tumor cells existed at same focus in liver and spleen, which mainly were myelocytoma cells and lymphosarcoma cells. The PCR-based diagnosis were performed as follows: the cellular DNA was extracted from the inoculated DF-1 cells; the specific fragments of 1100 bp and 924 bp were obtained by a PCR system with the diagnostic primers of ALV-B and ALV-J; and the PCR results for ALV-A, MDV and REV were all negative. Then, the amplified fragments of the two ALV-B stains were partially sequenced and shown an identity of 92.8%,94.7% with the prototype strain of ALV-B (RSV Schmidt-ruppin B). The identities of two ALV-J strains with the prototype strain HPRS-103 at 96.9%, 91.5%; The identities of two ALV-J strains with the American prototype strain at 85.9%, 81.5%. Our study had shown that ALV-B was isolated for the first time from the ALV-J infected commercial layer flocks in China. It also indicated that the chance of genetic recombination among various subgroups of ALV was increased.
authors.affiliation: College of Animal Science and Veterinary Medicine, Shandong Agricultural University, Tai'an 271018, China. gongzhenliu@126.com
authors.forename: Gong-Zhen
authors.initials: GZ
authors.lastname: Liu
authors.forename: Hong-Hai
authors.initials: HH
authors.lastname: Zhang
authors.forename: Qing
authors.initials: Q
authors.lastname: Liu
authors.forename: Bo
authors.initials: B
authors.lastname: Qiu
authors.forename: Feng
authors.initials: F
authors.lastname: Wang
authors.forename: Xiao-Wei
authors.initials: XW
authors.lastname: Wang
authors.forename: Hong-Bo
authors.initials: HB
authors.lastname: Chen
authors.forename: Zi-Qiang
authors.initials: ZQ
authors.lastname: Cheng
mesh_terms: D000818:Animals; D001353:Avian Leukosis / Q000473:pathology / Q000821:virology*; D001354:Avian Leukosis Virus / Q000145:classification / Q000235:genetics / Q000302:isolation & purification*; D002460:Cell Line; D002645:Chickens; D002681:China; D008099:Liver / Q000473:pathology / Q000821:virology; D008969:Molecular Sequence Data; D010802:Phylogeny; D011201:Poultry Diseases / Q000473:pathology / Q000821:virology*; D013154:Spleen / Q000473:pathology / Q000821:virology