In 1980, 49 samples of feces and 40 samples of leukocytes were collected from 2 flocks affected with an egg drop syndrome-1976 (EDS-76)-like disease in the Kyushu region for virus isolation in duck embryos and duck embryonic liver cells. As a result, heamagglutinating viruses were isolated only from 4 samples of feces.
The isolates had the same antigenicity and physicochemical properties as the JPA-1 strain of avian adenovirus, identified as EDS-76 virus in Japan. HI antibodies against the isolate (KE-80) were detected in more than 90% of the sera from the flocks.
Laying SPF hens and ducks inoculated perorally with the isolates began to show aberrant egg production 7 and 9 days after inoculation, respectively, and produced HI antibody.