The objective of this study was to instrument a serological assay for the epidemiological diagnosis of bovine babesiosis in Mexico, using the Babesia bigemina recombinant protein RAP‐1 (rRAP‐1α) as antigen. rRAP‐1α, r12d3 and rGP45 were the three recombinant antigens initially tested. Based on the highest titres obtained in the indirect ELISA (iELISA) with the positive control serum, using similar antigen concentrations, rRAP‐1α was selected for further use. The diagnostic sensitivity and specificity rates estimated for the iELISA with rRAP‐1α as antigen were 89.9% and 86.5%, respectively, while for the Indirect Fluorescent Antibody Test (IFAT), the gold standard assay, the sensitivity was 86.66% and the specificity was 95%. The ĸ agreement value determined was 0.52, indicating a moderate agreement between the iELISA and IFAT assays. The instrumented iELISA with rRAP‐1α as antigen shows an excellent specificity rate and an acceptable sensitivity that allows for the detection of antibodies to B. bigemina in cattle naturally exposed to the vector tick Rhipicephalus microplus. By using the iELISA‐rRAP‐1α, along with an iELISA with recombinant Merozoite Surface Antigen (rMSA‐1) for antibody determination against Babesia bovis in the serum samples collected from cattle at ‘La Posta’ experimental station in Mexico, a seroprevalence of 20.3% was estimated for B. bigemina and 19.4% for B. bovis, while 36.89% of samples were positive for both Babesia species. The iELISA test promises to be a safe and low‐cost type of diagnosis available to cattle producers in Mexico and would facilitate the definition of herd immunity status to implement measures of control adapted for the prevention of bovine babesiosis outbreaks.

中文翻译：

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使用重组蛋白作为抗原的间接ELISA的验证，以鉴定暴露于重瓣巴贝斯虫的动物。

这项研究的目的是使用大巴贝虫病（Babesia bigemina）为墨西哥的牛杆状杆菌病的流行病学诊断提供一种血清学检测方法重组蛋白RAP-1（rRAP-1α）作为抗原。rRAP-1α，r12d3和rGP45是最初测试的三种重组抗原。根据使用阳性对照血清在间接ELISA（iELISA）中获得的最高滴度，并使用相似的抗原浓度，选择了rRAP-1α进行进一步使用。以rRAP-1α作为抗原的iELISA的诊断敏感性和特异性估计分别为89.9％和86.5％，而对于间接荧光抗体试验（IFAT），金标准测定，敏感性为86.66％，特异性为95％。测得的ĸ一致性值为0.52，表明iELISA和IFAT分析之间存在中等程度的一致性。使用rRAP-1α作为抗原的仪器化iELISA显示出极好的特异性率和可接受的灵敏度，可以检测到牛双歧杆菌（B. bigemina）在自然暴露于微小的Rhipicephalus microplus的牛中。通过使用iELISA‐rRAP‐1α以及结合重组裂殖子表面抗原（rMSA‐1）的iELISA来测定在墨西哥``La Posta''实验站从牛身上采集的血清样品中的牛牛贝氏杆菌抗体，血清阳性率为20.3 ％估计为B. bigemina和19.4％牛巴贝虫，而样品的36.89％阳性两者巴贝斯种类。iELISA测试有望成为墨西哥牛生产者的一种安全且低成本的诊断方法，并将有助于定义牛群免疫状况，以实施适于预防牛杆状杆菌病暴发的控制措施。