Epizootiologic Studies on Akabane virus infections of Cattles in Kyungbuk

경북지방 소 Akabane병 발생과 중화항체가 분포조사

A considerably high rate of abnormal deliveries of unknown etiology was observed among dairy cattles from November 1988 to February 1989 and Korean native tattles from January to April 1990. The abnormal deliveries consisted of abortions, stillbirths and calf deformities refers to as congenital arthrogryposis hydranencephaly (AH )syndrome. In order to know the level of Akabane antibody of dairy cattle raised in Kyungbuk province, serum neutralization test was conducted with Akabane virus(OBE-1 strain) and HmLu(Hamster lung) cell line. The results were summarized as follows. 1. During 4 months(Nov. 1988-Feb. 1989), abortion (3 heads), stillbirth(1 head) and congenital abnormalities(13 heads) of newborn were occurred in 17 dairy cattles raised in Kyungbuk province. 2. During 4 months(Jan.-Apr.1990), stillbirth(2 heads) and congenital deformities (13 heads) of newborn were occurred in 15 Korean native tattles raised in Kyungbuk province. 3. In Fev, and Apr. 1990, 1,005 dairy cattles at 99 farms were investigated on the actual condition of possessing Akabane antibody. The result was that 1,000 heads (99.9%) in 1,005 dairy cattles reacted as positive condition in Akahane antibody. The antibody titer was from 4 to over 256. 4. 189 heads (18.8%) of 1,005 dairy cattles werw below antibody titer 8 and 816 heads (81.2%) were over 16. 5. Akabane antibody titer of east coast legions(Pohang Yeongil etc) was all over 16, that of internal legions (Yeongiu, Andong. etc) was relatively low, The result suggest that the vaccination for Akabane disease will be unnecessary for the time being because of possessing higher antibody titer reaction except the newly introduced cattle and Akabane virus was widely disseminated in kyungbuk province during the summer months in 1987 or 1988.