Molecular Detection and Identification ofBabesiaspp.,Theileriaspp., andAnaplasmaspp. in Sheep From Border Regions, Northwestern China

Babesia, Theileria, andAnaplasmaare important causative agents of tick-borne diseases that severely affect sheep. However, there is paucity in the occurrence genetic diversity of the infections of tick-borne diseases in sheep in border regions, northwestern China. In this study, nested polymerase chain reaction (nPCR) assays and gene sequencing were used to identify tick-borneBabesiaspp.,Theileriaspp., andAnaplasmaspp. infections in border regions, northwestern China. Out of 323 samples tested in this study, 225 (69.7%) sheep were infected withBabesiaspp.,Theileriaspp., andAnaplasmaspp. Two hundred six (63.8%), 60 (18.6%), 54 (16.7%), 51 (15.8%), 32 (9.9%), 19 (5.9%), and 16 (5.0%) were positive forA. ovis, B. motasi-like,A. bovis, T. uilenbergi, A. phagocytophilum, T. luwenshuni, andB. motasi-like Xinjiang, respectively. The most common dual infection was withA. ovisandB. motasi-like while the most frequent triple coinfection wasA. ovis, B. motasi-like, andT. uilenbergiwith coinfection rates of 17.0% (55/323) and 5.0% (16/323), respectively. Sequencing analysis indicated thatA. ovis MSP4, A. phagocytophilum epank1, A. bovis16S rRNA,B. motasi-likerap1-b, B. motasi-like Xinjiangrap1-a, T. luwenshuni18S rRNA, andT. uilenbergi18S rRNA from border regions, northwestern China, showed 99-100% identity with documented isolates from other countries. To the best of the authors' knowledge, this is the first report ofT. uilenbergiandT. luwenshuniinfections of sheep in border regions, northwestern China. Furthermore, these findings provide important data for understanding the distribution ofBabesia, Theileria, andAnaplasmain sheep between border countries and China.