First Report of Seroprevalence and Risk Factors of Infection in Tibetan Sheep in China.

is an intracellular protozoan parasite which can cause abortion and stillbirth in ruminants. However, there is no information on Tibetan sheep infection in China. A total of 2187 serum samples were collected from Tibetan sheep in the major production areas of Luqu, Maqu, and Tianzhu in Gansu province, and Nyingchi in southeast Tibet, China. All samples were analyzed for the presence of antibodies to using a competitive-inhibition enzyme-linked immunoassay. Of the 2187 serum samples, 184 (8.4%, 95% CI 7.3-9.6) were tested seropositive. The seroprevalence ranged from 4.4% (95% CI 1.4-7.4) to 11.3% (95% CI 8.2-14.4) among different regions, seasons, ages, and pregnancies, and there was no statistical significance among those groups ( > 0.05). Seroprevalence in male (10.8% 69/638) (95% CI 8.4-13.2) was significantly higher than in female (7.4% 115/1549) (OR =1.51, 95% CI 6.1-8.7) ( < 0.01). To our knowledge, this is the first report of seroprevalence in Tibetan sheep in China, which provides baseline data for the prevention and control of infection in Tibetan sheep.