Abstract: | A serial 34-chicken pancreas passage of avian encephalomyelitis virus by oral administration was successful. Oral inoculation test with 4 passaged viruses showed rapid infection of the duodenal wall and unchangeable infection of pancreas diminishing the viral invasiveness to other organs. The passaged virus caused neither detectable viremia nor clinical avian encephalomyelitis signs and produced neutralizing antibody of high titers. |