Reproduction of inclusion body hepatitis in conventionally raised chickens inoculated with a New Zealand isolate of avian adenovirus

Conventionally raised chickens were inoculated with a local isolate of serotype 8 of avian adenovirus by an oral or intraperitoneal route, or were exposed to the infection by contact. Fatal hepatitis, resembling inclusion body hepatitis, occurred in 30% and 45% of the birds inoculated by the oral and intraperitoneal routes respectively, and severe growth depression was recorded in survivors and in birds in contact. Birds which had maternally derived virus neutralising antibody titres of 64 or greater at the time of viral exposure did not succumb to fatal infection, but their growth rates were significantly depressed.