Avian leukosis virus subgroup-J (ALV-J)‎ infection in native breeder female chickens crossed with infected foreign broiler males

الملخص EN

A study has been conducted to investigate the potential transmission of ALV-J infection through cross-breeding at 18 weeks of age between three native breeder female flocks serologically negative for ALV-J antibody and ALV-common antigen and commercial foreign broiler males which originated from an ALV-J infected imported broiler breeder farm.

At 28-30 weeks of age the 3 cross-bred flocks, reared at different localities in El-Gharbia Governorate suffered from neoplasms, and the native females revealed more extensive pathognomonic visceral, bone,and ossified cartilage tumor formation than the foreign broiler male chickens.

Histopathologically, immature myelocyte proliferation with characteristic esionophilic cytoplasmic granules, were present in the bone marrow of various bones and in the periostium of the ribs, vertebrae, synsarcum and ossified cartilages of trachea and larynx as well as infiltrating the visceral organs.

The sciatic nerve revealed perineurium infiltration with myelocytes and pleomorphic lymphocytes.

Furthermore, intranuclear inclusions were observed in myelocytes, suggesting concurrent viral infection .

ALV-J antibodies were detected in 100% of serum and egg-yolk samples from the cross-bred flocks and in 50-80% and 67% of serum and egg-yolk samples from the original imported broiler breeder flocks, respectively.

Moreover, ALV-common antigen was detected in 20-40% and 0% of serum and egg-albumen samples from cross-bred chickens, respectively, and in 50%-90% and 0% of serum and egg-albumen samples from the original imported broiler breeder farm, respectively.

These results support the transmission of ALV-J infection from the imported original broiler breeders to their progeny which in turn transmitted the infection to native female chickens with negative history of ALV-J infection .