中文摘要：

目的 建立驽巴贝虫（Babesia caballi）和马泰勒虫（Theileria equi）的双重PCR检测方法。 方法 根据GenBank发表的驽巴贝虫裂殖子mRNA BC48基因保守序列和马泰勒虫核糖体小亚基18 s rRNA基因保守序列，设计、合成2对特异性引物，经优化反应条件，建立双重PCR检测方法，并检测该方法的特异性和敏感性。用该双重PCR法对采集于伊犁地区马疑似病例全血样品进行检测，并与镜检法、常规PCR和荧光PCR的结果进行比较。 结果 建立的双重PCR法可特异性地扩增驽巴贝虫和马泰勒虫的相应目的条带，分别长约155 bp和280 bp，而对其他种属的双芽巴贝虫（B. bigemina）、环形泰勒虫（T. annulata）、瑟氏泰勒虫（T. sergenti）、刚地弓形虫（Toxoplasma gondii）、犬新孢子虫（Neospora caninum）和伊氏锥虫（Trypanosoma evansi）进行扩增未见相应片段。该方法对驽巴贝虫和马泰勒虫的最低检出浓度分别为4.85×105拷贝/μl和4.85×104拷贝/μl。对采集的24份疑似血样进行双重PCR扩增，驽巴贝虫的阳性率为45.8%（11/24），马泰勒虫的阳性率为75.0%（18/24），镜检法、常规PCR和荧光PCR与双重PCR检测的符合率分别为91.7%（22/24）、95.8%（23/24）和95.8%（23/24）。 结论 建立了可同时检测驽巴贝虫和马泰勒虫的双重PCR方法。

英文摘要：

Objective To develop a duplex PCR assay for detection of Babesia caballi and Theileria equi. Methods Two pairs of primers were designed according to the BC48 gene of B. caballi and 18 s rRNA gene of T. equi， and a duplex PCR assay was developed by the optimization of reaction conditions. The specificity， sensitivity and reliability of the method were tested. The horse blood samples of suspected cases were collected from Yili region， and detected by the duplex PCR， microspopy， conventional PCR， and fluorescence quantitative PCR， and the results were compared. Results Using the duplex PCR assay， the specific fragments of 155 bp and 280 bp were amplified from DNA samples of B. caballi and T. equi， respectively. No specific fragment was amplified from DNA samples of B. bigemina、 Theilerdia annulata， Theilerdia sergenti， Toxoplasma gondii， Neospora caninum， and Trypanosoma evansi. The limit of detection was 4.85×105 copies/μl for B. caballi DNA and 4.85×104 copies/μl for T. equi DNA， respectively. Among the 24 blood samples， 11 were found B. caballi-positive by the duplex PCR assay， and 18 were T. equi-positive. The coincidence rate of microscopy， conventional PCR， and fluorescence quantitative PCR with duplex PCR was 91.7%（22/24）， 95.8%（23/24）， and 95.8%（23/24）， respectively. Conclusion A duplex PCR assay for simultaneous detection of B. caballi and T. equi is established.