[Isolation and identification of a subgroup B avian leukosis virus from chickens of Chinese native breed Luhua].

By inoculation of blood samples in DF-1 (C/E) cell culture, an exogenous avian leukosis virus (ALV) strain SDAU09C2 was isolated from a breeder farm of Chinese native breed "Luhua" in Shandong province. Comparisons of the amino acid sequence of env gene gp85 from the isolate with those from other ALV reference strains of different subgroups indicated that SDAU09C2 had the highest gp85 identity to two reference strains of subgroup B of 92.5%. Its gp85 identity to other chicken ALV subgroups A, C, D, E was in the range of 73.2%-87.9%. The identity to subgroup J was only 30.3%-32.4%. This is the first report on isolation and identification of ALV-B and its gp85 from Chinese native breed chickens.