蒙古国科布多省牛新孢子虫病PCR诊断初报

Preliminary report on PCR diagnosis of Neosporosis in cattle in Hovd,Mongolia

为了查明科布多省牛只是否感染犬新孢子虫(Neospora caninum)并造成流产隐患,本文应用PCR方法,以新孢子虫NC-5为诊断靶基因,对随机采集科布多省3个检测点的120份牛血样进行DNA提取、扩增诊断,并基因测序。结果显示,成功获得了231 bp目的片段;测序结果经BLAST比对,与犬新孢子虫新西兰株(GenBank登录号:AY459289.1)同源性达99%,构建的系统发育树中,本株与犬新孢子虫聚为一支,置信度达99%。说明科布多省牛只已感染了新孢子虫;在3个检测点中,艾尔登特苏木乡感染率最高,为12.7%(7/55),总感染率为7.5%(9/120)。本文初次报道蒙古国科布多省牛群不同程度的感染新孢子虫,应该引起重视。

This study was to determine whether Neospora caninum had infected cattle in the province of Hovd, causing abortion risk. DNA extraction, amplification diagnosis and gene sequencing were performed on 120 cattle blood samples collected at three experimental sites in Kobuduo Province using PCR with Neospora NC-5 as the diagnostic target gene. The results showed that a 231 bp target fragment was successfully obtained. The sequencing results were compared by BLAST, and the homology of the present strain with the Neospora caninum New Zealand strain(GenBank accession number: AY459289.1) was 99%, and the constructed phylogenetic tree showed that the present strain and Neospora caninum were in one cluster, at a confidence level of 99%, indicating that the cattle in the province of Hovd had been infected with Neospora caninum. Among the three detection sites, the infection rate of Eldente Sumu Town was the highest, at 12.7%(7/55), with the total infection rate being 7.5%(9/120). It was estimated that Neosporosis had infected the cattle herds in the region at varying degrees, resulting in abortion of the cows. This was the first report on infection in cattle in Hovd, Mongolia with Neospora caninum;andmuch attention should be paid to more prevention and control of the disease.