Serological evidence of antibodies against Chlamydophila abortus in free-ranging yak (Poephagus grunniens) in Arunachal Pradesh, India.

Serum samples were randomly collected from 172 free-ranging yak (Poephagus grunniens, presently Bos grunniens) from six different yak tracts of Arunachal Pradesh, India, and subjected to enzyme-linked immunosorbent assay to detect the presence of specific antibodies against Chlamydophila abortus. The overall prevalence of this disease in yak was 35%. The prevalence of Cp. abortus-specific antibodies was significantly higher in yak cows (41%) than among bulls (25%). The highest prevalence (39%: 95% confidence interval [Cl] = 27, 55) was found in yak between one and three years of age, while the lowest prevalence (20%: 95% CI = 10, 41) was reported in yak below one year of age.