Vertical transmission of avian adenovirus associated with inclusion body hepatitis.

Using an indirect enzyme-linked immunsorbent assay, avian adenoviral antigens were detected in the yolk and albumen of eggs derived from broiler breeder chickens which were known to be infected with a strain of virus capable of causing inclusion body hepatitis. Viral antigens were detected in egg yolk (16/60) more frequently than in the albumen (5/60). Direct detection of viral antigens in eggs strongly supports the hypothesis that transovarian transmission of inclusion body hepatitis virus occurs if infection is present in breeder flocks.