With the purpose of studying the prevalence of equine viral arteritis in horses raised in São Paulo State, Brazil, by the standard microtiter serum neutralization test, 659 serum samples were investigated. The prevalence of antibodies in the horse population was 18.2%, which was significantly higher in Mangalarga horses (33.3%) than in any other breed (Thoroughbred, Arab, Quarter Horse, mixed breeds and others). The distribuition of horses by age showed that horses between 6 to 24 months of age (30.4%) had a higher prevalence (30.4%) rate than others. The female horses prevalence rate of 22.9% was significantly higher than in male horses.
Viral arteritis; equines; prevalence; serum neutralization
