Molecular Detection of Theileria ovis, Anaplasma ovis, and Rickettsia spp. in Rhipicephalus turanicus and Hyalomma anatolicum Collected from Sheep in Southern Xinjiang, China

Abstract

The Xinjiang Uygur Autonomous Region (Xinjiang) borders eight countries and has a complex geographic environment. There are almost 45.696 million herded sheep in Xinjiang, which occupies 13.80% of China's sheep farming industry. However, there is a scarcity of reports investigating the role of sheep or ticks in Xinjiang in transmitting tick-borne diseases (TBDs). A total of 894 ticks (298 tick pools) were collected from sheep in southern Xinjiang. Out of the 298 tick pools investigated in this study, Rhipicephalus turanicus (Rh. turanicus) and Hyalomma anatolicum (H. anatolicum) were identified through morphological and molecular sequencing. In the southern part of Xinjiang, 142 (47.65%), 86 (28.86%), and 60 (20.13%) tick pools were positive for Rickettsia spp., Theileria spp., and Anaplasma spp., respectively. Interestingly, the infection rate of Rickettsia spp. (73%, 35.10%, and 28.56-41.64%) was higher in Rh. turanicus pools than in H. anatolicum pools (4%, 4.44%, and 0.10-8.79%) in this study. Fifty-one tick pools were found to harbor two pathogens, while nineteen tick pools were detected to have the three pathogens. Our findings indicate the presence of Rickettsia spp., Theileria spp., and Anaplasma spp. potentially transmitted by H. anatolicum and Rh. turanicus in sheep in southern Xinjiang, China.