【摘要】 为了解云南省牛环曲病毒（BToV）的流行特点及遗传进化情况，2021—2023年在红河、大理、曲靖、楚雄等9个市13个县（区）15个牛场采集了655份粪便样品进行BToV核酸检测，并对部分BToV阳性样品进行了HE基因序列分析。核酸检测结果显示：BToV总阳性率为10.8%(71/655)；扩增得到6条完整的BToV HE基因序列，分属于BToV Ⅱ型和BToV Ⅲ型，与40条参考序列的核苷酸同源性为69.1%～99.8%；基因重组分析结果显示：存在2个重组现象，其亲本均为BToV Ⅱ型毒株和青藏高原藏羚羊源毒株，重组区域位于凝集素结构域R；基因选择压力分析结果显示：BToV HE基因在宿主机体和生存环境中的进化趋势以中性选择为主。结果表明：云南省牛场存在BToV感染；流行毒株中存在重组毒株，其可能由国内奶牛BToV毒株重组而来，且出现跨物种重组现象，该重组事件可能对病毒与受体结合过程产生影响。更多还原

【Abstract】 In order to identify the prevalence status and genetic evolution of bovine torovirus(BToV)in Yunnan Province,655 faecal samples were collected from 15 cattle farms in 13 counties(districts)in 9 cities,including Honghe,Dali,Qujing and Chuxiong and other cities,from 2021 to 2023,to detect BToV nucleic acids,and then HE gene sequences were analyzed for some BToV-positive samples. The nucleic acid testing results indicated that the total positive rate of BToV was 10.8%(71/655);6 complete BToV HE gene sequences were amplified,falling into BToV Ⅱ and BToV Ⅲ type,respectively,and their nucleotide homology with 40 reference sequences ranged from 69.1% to 99.8%;the gene recombination results revealed that there were two kinds of recombinations,whose parents were both the BToV Ⅱ strain and the one originated from Tibetan antelope of Tibetan Plateau,and the recombination region was located in the structural domain R of the lectin;the gene selection pressure assay results showed that the evolutionary tendency of BToV HE gene in the host organisms and its survival environment was dominated by neutral selection. In conclusion,BToV existed in cattle farms in Yunnan Province,including recombinant strains that might be recombined from the BToV strains in domestic cows,and cross-species recombination was observed,which would likely affect the process where the virus bound to receptors.更多还原