Fulton R W, Nicholson S S, Pearson N J, Potter M T, Archbald L F, Pearson J E, Jochim M M
Am J Vet Res. 1982 May;43(5):887-91.
Bluetongue virus (BTV) serotype 17 was isolated from cattle with clinical signs of bluetongue disease during 1978 and 1979 epizootics. Bovine sera from 6 herds located in an epizootic region were examined in 1979 for antibodies, using an immunodiffusion (ID) test. Of 300 sera, 164 (54.7%) were seropositive. Sera from statewide surveys of Louisiana cattle in July to August 1980 and December 1980 to January 1981 were tested for BTV antibodies, using the ID test. Fifty-eight of 70 herds (82.9%) and 164 of 597 (27.5%) individual cattle tested in July to August 1980 were seropositive. Fifty-four of 63 (85.7%) herds and 170 of 600 (28.3%) individual cattle tested in December 1980 to January 1981 were seropositive. Significant differences (P less than 0.01) were found in the seropositive rates between the various geographic regions of the state during each survey. Adult breeding-age cattle in 3 sentinel herds were tested for BTV antibodies beginning in 1976 and continuing through January 1981. During this interval, the seropositive rate in 2 of 3 herds was increased. Also, individual cattle in all 3 of these herds converted from seronegative to seropositive, indicating exposure during a particular interval for each herd. The age distribution of seropositive cattle in a dairy indicated that 2-year-old cattle had a seropositive rate comparable with that of older animals in the herd, suggesting that the 2-year-old animals had been exposed to a BTV before they entered the breeding herd.
蓝舌病病毒17型于1978年至1979年的蓝舌病疫情期间，从出现蓝舌病临床症状的牛身上分离得到。1979年，使用免疫扩散（ID）试验对位于一个疫区的6个牛群的牛血清进行了抗体检测。在300份血清中，164份（54.7%）呈血清阳性。1980年7月至8月以及1980年12月至1981年1月对路易斯安那州全州牛群进行调查时采集的血清，采用ID试验检测蓝舌病病毒抗体。1980年7月至8月检测的70个牛群中有58个（82.9%）呈血清阳性，597头牛中有164头（27.5%）呈血清阳性。1980年12月至1981年1月检测的63个牛群中有54个（85.7%）呈血清阳性，600头牛中有170头（28.3%）呈血清阳性。每次调查期间，该州不同地理区域之间的血清阳性率存在显著差异（P小于0.01）。从1976年开始，对3个哨兵牛群中的成年繁殖年龄牛进行蓝舌病病毒抗体检测，一直持续到1981年1月。在此期间，3个牛群中有2个的血清阳性率有所上升。此外，这3个牛群中的所有个体牛都从血清阴性转为血清阳性，表明每个牛群在特定时间段内接触过病毒。一个奶牛场中血清阳性牛的年龄分布表明，2岁的牛血清阳性率与牛群中年龄较大的动物相当，这表明2岁的动物在进入繁殖牛群之前就接触过蓝舌病病毒。
