From November 1978 to April 1979, there occurred among cows many cases of abortion, premature birth, stillbirth and congenital arthrogryposis or hydranencephaly in Kyongki-do province in Korea. Epizootics recurred between February and May, 1980 in the same area. Six calves born at 8 or 10 months of gestation were examined by means of pathology and one of the calves was examined by serological test. And a survey on local occurrence of the disease in other than Kyongki-do province, was conducted.
1. At necropsy, some calves showed distinct lesions such deformities of the limbs and the vertebrae as arthrogryposis or scoliosis. Other calves revealed arthrogryposis and partial or total deficience of the cerebral hemispheres with hydranencephaly.
2. In the calves with deformities the skeletal muscle showed histologically severe hypoplasia of the muscle fibers with cellular infiltration. In the central nervous system of the calves with hydranencephaly there were minute cystic cavitation and the decrease of ventral horn cells of the spinal cord in the number.
3. Similar epizootics were also observed in the same season in the other several provinces such as Chungcheongnam-do, Kangwon-do and Jeonrabuk-do.
4. Anti-Akabane virus antibody was detected in precolostral blood from the calf with arthroglposis and hydranencephaly syndrome.
5. On these findings of the disease it was diagnosed as Akabane disease presenting the first report on the epizootics in Korea.
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