From June, 1974, to March, 1975, a total of 5, 566 serum samples were collected from dairy cattle in Shimane prefecture and tested for neutralizing anti-body against Akabane virus, the causative agent of abnormal birth in cattle. Of 3, 653 cattle of different age, the frequency of positive reactors was 19.5% in those born after 1973, 44.5% in those born in 1969 to 1972, and 49.0% in those born in 1965 to 1968.
A total of 63, 52, and 83 cows were associated with abortion, stillbirth, and deformed calving and pre-sented a positive rate of 44.6, 61.5 and 76.2%, res-pectively. When 57 pregnant dairy cows introduced from Hok-kaido free from an outbreak, 27 introduced in May, 1973, were positive for antibody, but 30 introduced in March, 1974, and May, 1974 were negative. Of the 27 cows having antibody, two were involved in still-birth and two in deformed calving.
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