牛新孢子虫病和弓形虫病的流行病学调查

Epidemiological investigations of infections with Neospora caninum and Toxoplasma gondii in cattle and water buffaloes

为了调查我国牛新孢子虫和弓形虫的感染情况，应用新孢子虫酶联免疫吸附试验（ELISA）和弓形虫间接血凝试验（IAT）分别检测了来自国内10个省（市、自治区）的262份乳牛、10份肉牛和40份水牛血清。结果显示，乳牛新孢子虫的抗体阳性率为17．2％，弓形虫的抗体阳性率为2．3％，没有检测到既有新抱子虫抗体又有弓形虫抗体的乳牛血清。各牛场所检乳牛血清的新孢子虫抗体阳性率在0～34．4％之间。在水牛和肉牛血清中未检测到新孢子虫抗体和弓形虫抗体。流产乳牛血清的新孢子虫抗体阳性率为20．2％，未流产乳牛为16．1％，其中血清抗体阳性乳牛主要在妊娠中晚期流产。各个年龄段乳牛血清的抗体阳性率差异不显著（P〉0．05）。不同妊娠胎次的乳牛血清抗体阳性率差异不显著（P〉0．05）。确认新孢子虫病在国内大部分牛场存在。

An epidemiological survey of Neospora caninum and Toxoplasma gondii infections in cattle and water buffaloes was carried out in the People＇s Republic of China. Serum samples were obtained from dairy（n=262, 9 herds from 9 provinces）and beef cattle（n=10, one herd ） and water buffaloes（n= 40 ） in China. All sera were tested for seroprevalence of N. caninum and T. gondii by the ELISA and the indirect agglutination test （IAT）, respectively. The overall seroprevalence of N. caninum in dairy cattle was 17.2% （45/262）, and antibodies to T. gondii were present in 6 cows （2.3%）. No beef cattle or water buffaloes were found to have antibodies to both T. gondii and N. caninum. The seroprevalence of N. caninum in 9 herds ranged from 0 to 34.40%, and the difference between herds was statistically significant （P〈0.05）. None of the cows had antibodies against either T. gondii or N. caninum. The seroprevalence of N. caninum in abortive cows （20.2%） was higher than that in non-abortive cows （16.6%）, but the difference was not statistically significant （P〉0.05）. The seropositive cows aborted mainly during second and third trimesters of gestation. The differences of seroprevalence were not statistically significant among different age groups and parturition groups （P〉0.05）, respectively.