新疆南疆部分地区绵羊支原体感染的分子流行病学调查

Molecular epidemiological investigation of sheep mycoplasma infection in parts of southern Xinjiang

为了解新疆南疆地区规模化羊场支原体感染的流行情况,首先采用PCR技术对新疆南疆3个县的5个规模化羊场132例鼻拭子、6例肺样品进行初步检测;然后利用支原体液体培养基MTB及固体培养基MTA对PCR阳性样本进行分离培养、鉴定;并选取部分代表株,对其16S rRNA基因进行序列测定,分析其分子特征。PCR结果显示,该地区支原体总体阳性率为26.1%(36/138),绵羊肺炎支原体阳性率为14.5%(20/138),精氨酸支原体的阳性率为11.6%(16/138),其中库车县的支原体阳性率最高,达43.5%(27/62)。系统进化树显示:绵羊肺炎支原体分离株中,WSMO株与美国株的亲缘关系较近,其他分离株单独聚为一支;精氨酸支原体分离株中,YJSMA与南非株的亲缘关系较近,其他分离株单独聚为一支。这说明该地区菌株由于地理环境或长途运输导致与国外菌株的亲缘关系较近,同时存在一定程度变异造成基因型的差异。本研究结果可为该地区绵羊支原体病的有效防治提供参考。

To investigate the prevalence of mycoplasma infection in sheep farms in southern Xinjiang,132 nasal swabs and 6 lungs were detected in five sheep farms in three counties in southern Xinjiang by PCR.Then mycoplasma liquid culture medium MTB and solid culture medium MTA were used to isolate and identify PCR positive samples.The 16S rRNA gene of selected representative strains was sequenced to analyze their molecular characteristics.The results showed that the overall positive rate of mycoplasma was 26.1%(36/138),the positive rate of Mycoplasma ovipneumoniae(Mo)was 14.5%(20/138),and the positive rate of Mycoplasma arginini(Ma)was 11.6%(16/138).The highest positive rate was 43.5%(27/62)in Kuqa County.Phylogenetic tree showed that the WSMO strain of Mo isolates was closely related to the American strain,and the other isolates were isolated into a branch.Among the isolates of Ma,YJSMA was closely related to the South African strain,and the other isolates were isolated into a branch. It indicates that the strains in this region are closely related to the foreignstrain due to geographical environment or long-distance transportation,and there is a certain degreeof variation resulting in genotype differences. This study can provide reference for the effectiveprevention and treatment of mycoplasma infection in sheep in this region.