Detection of Bovine Torovirus in Yunnan Province and Polymorphic Assay of Its HE Gene
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.
万方数据
维普
