广东省乳牛隐孢子虫病的流行病学调查

对广东省 10个奶牛场进行了隐孢子虫病的流行病学调查 ,并按大致 10 %的采样率采集了 10 87头乳牛的新鲜粪便 ,以饱和蔗糖漂浮法和改良抗酸染色法检查隐孢子虫卵囊 ,其中检出卵囊的阳性牛 92头 ,阳性率为 8.4 6 % ;有 7个场检出隐孢子虫卵囊 ,场阳性率为 70 %。这 7个奶牛场的卵囊阳性检出率分别是 10 .0 0 %、7.19%、6 .6 7%、9.80 %、6 .72 %、12 .76 %和 6 .72 %。调查发现 ,乳牛隐孢子虫的阳性率和感染强度与乳牛年龄呈负相关关系 ,而且可能与气候有关 ;所检出的隐孢子虫卵囊经形态学鉴定为鼠隐孢子虫 (Cryptosporidiummuris)。

Prevalence of Cryptosporidium infection in cows in Guangdong

An epidemiological survey in cows was carried out on 10 farms in Guangdong Province of China. A total of 1 087 rectal fecal samples were collected from each cow and analyzed by the modified acid-fast staining and flotation technique using saturated sucrose. The prevalence rates on the 10 farms were 10.00%, 7.19%, 6.67%, 9.80%, 6.72%, 12.76% and 6.72%, respectively, and the average prevalence rate was 8.46%. Shedding of Cryptosporium oocysts occurred in all ages and among categories of cattle but pinked (10.82%) in calves of 1-3 months old. The infection rate was 9.61% in autumn and winter, and 6.86% in spring. The results indicated that the calves are more susceptible to cryptosporidiosis than the heifers and the cows, and the infection varies in different seasons. The staining and morphological appearance of the oocysts indicated that the Cryptosporidium species on the farms in Guangdong was C.muris.