Diagnosis and sequence analysis of avian leukosis virus subgroup J isolated from Chinese Partridge Shank chickens

ABSTRACT The diagnosis of avian leukosis virus subgroup J (ALV-J) infection in Chinese Partridge Shank chickens was confirmed by necropsy, histopatho-logical examinations, antibody tests, viral isolation, immunofluorescence assays, and sequence analysis. Myelocytoma, myeloma, and fibrosarcoma were simul-taneously found in Partridge Shank flock with ALV-J infection. Sequence analysis of the env genes of ALV-J demonstrated that both gp85 and gp37 were highly homologous among the three strains from local chick-ens of those among ALV-J strains isolated from white meat-type chickens. The phylogenetic trees indicated that the three strains isolated in this study were closely related to reference strains isolated in so-called Chinese yellow chickens and some strains isolated from white meat-type chickens, both from the USA and China. The observed ALV-J infection was the first report on Par-tridge Shank chickens, and myelocytoma, myeloma, and fibrosarcoma were found at the same time in this batch of local chickens. Key words: Avian leukosis virus subgroup J, Partridge Shank chickens, comprehensive diagnosis, sequence analysi