关键词: 禽白血病, 核心群, 净化

Abstract: Avian leukosis，group of diseases designates a variety of transmissible benign and malignant neoplasms of chickens caused by members of the avian retrovirus family. Notably，Exogenous avian leukosis viruses （ALVs），including the subgroups A，B，C，D，J，and K has certain pathogenicity and has induced great economic loss to the poultry industry since 1990s. Vertical transmission via directly infected chicken embryos is the main transmission route，therefore，it is crucial to control avian leukosis virus by well eradication of vertical transmission of ALV in broiler breeder flock. In this study，we analyzed the positive incidence rate of ALV in two ALV well?eradicated broiler breeder flocks and their offspring，by virus isolation，egg albumen p27 detection，and pathological analysis. Our results showed that the ALV positive rate in different generations were really low，even close to zero，which strongly suggest that an excellent effect of good ALV eradication in broiler breeder flock will produce offsping with extremely low positive rate of ALV.

Key words: Avian leukosis, Nucleus flocks, Eradication