Seroprevalence and associated risk factors of Toxoplasma gondii infection in yaks (Bos grunniens) on the Qinghai-Tibetan Plateau of China

Toxoplasma gondii is an intracellular parasite that is extensively prevalent globally. Studies have indicated the presence of T. gondii infection in animals in some provinces of China, but little is known about T. gondii infection in yaks (Bos grunniens) on the Qinghai-Tibetan Plateau. In the current study, to determine the seroprevalence and associated risk factors of T. gondii, a total of 2784 serum samples were collected from 18 different sampling sites in eight counties of the Qinghai and Tibet regions of China from 2018 to 2019. Serum antibodies against T. gondii were detected in 261 yaks (9.38%) via enzyme-linked immunosorbent assay (ELISA). We found that seroprevalence differed significantly among different counties (ranging from 5.41% in Gangcha to 19.79% in Datong), by year in the Tibet Autonomous Region (from 2.34% in 2018 to 13.24% in 2019), and by age (from 5.59% in 0 < year <= 1 to 11.76% in year > 7) (p < 0.05). Climate, geographical conditions, and age are the main factors influencing T. gondii infection in yaks in these regions. Therefore, our study provides a data reference for public health and prevention of yak toxoplasmosis.