PDF(Pubmed)
Abstract：
Bovine neosporosis is a widespread parasitic disease associated with significant economic losses. Its effects on the reproductive performance of cows have resulted in losses that run into the hundreds of millions of US dollars in dairy industries in various countries (Reichel et al., Int J Parasitol 43:133-142, 2013). Due to outdated and scant information on the occurrence of Neospora caninum infection in South Africa, the study aimed to determine the seroprevalence and risk factors associated with infection in dairy cattle in South Africa. A total of 1401 blood samples were randomly collected from cattle on 48 dairy farms in seven of the nine provinces in South Africa. A close-ended questionnaire was used in a cross-sectional study to obtain farm-level and animal-level data. Serological testing was done using a commercial IDvet Screen® Neospora caninum Indirect ELISA. An overall seroprevalence, adjusted for test sensitivity and specificity, of 2.3% (95% CI, 1.3-4.1) was detected and 48% (23/48) of sampled farms had at least one animal testing positive. The highest seroprevalence of N. caninum was in the KwaZulu-Natal province with 7.5% (95% CI, 3.8-14.3), and the lowest in Western Cape with 0.1% (95% CI, 0-1.2). The highest within-farm seroprevalence of 25% was detected on a farm in the North West Province. In a multivariable logistic regression model, the odds of N. caninum seropositivity were higher in Holstein-Friesian cattle when compared to other breeds. Good hygiene was identified as a protective factor. Cattle left out on pasture had increased odds of testing positive for N. caninum compared to those that were penned. The odds of testing seropositive for N. caninum was higher on farms that practised segregation of cattle into different age groups. The purchase of replacement animals was a significant risk factor, as open herds had increased odds of N. caninum seropositivity. Cattle on farms that did not have a specific calving location were more likely to be seropositive. This is the first such study in South Africa and shows that N. caninum is widely distributed in the country at a low seroprevalence, but it may be a cause of concern on certain farms.
摘要：
牛新孢子虫病是一种广泛存在的寄生虫病，伴随着巨大的经济损失。它对奶牛繁殖性能的影响已导致损失，在各个国家的乳制品行业中损失了数亿美元（Reichel等人。,IntJParasitol43:133-142,2013)。由于有关南非新孢子虫感染发生的信息过时且很少，该研究旨在确定南非奶牛感染的血清阳性率和危险因素。从南非9个省中的7个省的48个奶牛场的牛中随机收集了1401个血液样本。在横断面研究中使用封闭式问卷来获得农场级和动物级数据。使用商业IDvetScreen®犬新孢子虫间接ELISA进行血清学测试。总体血清阳性率，调整测试灵敏度和特异性，2.3%(95%CI,1.3-4.1)的样本农场检测到,48%(23/48)的样本农场至少有一次动物试验呈阳性.最高血清阳性率在夸祖鲁-纳塔尔省，为7.5％（95％CI，3.8-14.3），西开普省最低，为0.1%(95%CI，0-1.2)。在西北省的一个农场中检测到最高的农场内血清阳性率为25％。在多变量逻辑回归模型中，与其他品种相比，荷斯坦-弗利西亚牛的犬只血清阳性的几率更高。良好的卫生习惯被认为是保护因素。与饲养的牛相比，在牧场上被遗漏的牛对犬的检测呈阳性的几率增加了。在实行将牛隔离到不同年龄段的农场中，犬牛血清阳性检测的几率更高。购买替代动物是一个重要的风险因素，因为开放牛群增加了犬瘟病菌血清阳性的几率。没有特定产卵地点的农场的牛更有可能呈血清阳性。这是南非的第一个这样的研究，表明犬齿菌在该国广泛分布，血清阳性率低，但这可能会引起某些农场的关注。
