2005年上海地区乳牛球虫感染的季节动态

为了解上海地区乳牛球虫感染的季节变化情况,对上海地区3个牧场乳牛抽样直肠采集粪便,检查了718头乳牛粪样。结果,查出球虫阳性牛269头,平均感染率为37.46%,其中1月龄以内牛的感染率为33.89%,1~12月龄牛的感染率为42.33%,12月龄以上牛的感染率为25.95%。平均感染率最高的4月份为44.44%,最低的8月份为28.57%。3个牧场球虫阳性牛的感染强度(OPG值)为0~169 000个,平均OPG值为9 477个,其中1月龄以内牛的OPG值为8 270个,1~12月龄牛的OPG值为4 318个,12月龄以上牛的OPG值为145个。调查发现了6种球虫,分别是牛艾美球虫(Eimeria bovis)、椭圆艾美球虫(E.ellipsoidalis)、邱氏艾美球虫(E.zurnii)、怀俄明艾美球虫(E.wyomingensis)、柱状艾美球虫(E.cylindri-ca)、亚球形艾美球虫(E.subspherica)。结果表明,2005年上海地区乳牛球虫感染率无明显季节差异,12月龄内乳牛的球虫感染率与感染强度均明显高于12月龄以上乳牛,乳牛球虫的优势虫种为牛艾美球虫、椭圆艾美球虫、邱氏艾美球虫。

Seasonal changes of coccidia infection in dairy cows in Shanghai area in 2005

To understand seasonal changes of dairy cow coccidia infections in Shanghai,718 dairy cows were investigated on 3 dairy cow farms,and feces were collected from cecum and observed by microscope.Coccidia oocysts were found in 269 faecal samples from the cows and the average of infection rate was 37.46% in 2005.The highest infection rate was 44.44% in April and the lowest was 28.57% in August.The OPG values of faecal samples from the cows younger than 1 month,the cows aged 1-12 months and the cows older than 12 months were 8270,4318 and 145 respectively,and the mean OPG values was 9477.Six Eimeria species were identified,including E.bovis,E.ellipsoidalis,E.zurnii,E.wyomingensis,E.cylindrical and E.subspherica.It was concluded that the no difference of infection rates was observed among different months in 2005.The infection rate of the cow younger than 12 months was higher than the cow older than 12 months,and the dominant species were E.bovis,E.ellipsoidalis and E.zurnii in dairy cows in Shanghai area in 2005.