Seroprevalence of antibodies to Sarcocystis neurona in horses residing in Ohio

Abstract

Objective - To determine the seroprevalence of serum antibodies to Sarcocystis neurons in horses residing in Ohio. Design - Prevalence survey. Sample Population- Serum fiom samples from 1.056 horses. Serum was collected on every 36th sample submitted to the Ohio State Diagnostic Laboratory for testing for equire infectious anemia. Procedure- Serum was frozen at - 80 C and analyzed for antibodies to S neurona. using a western blot. Information regaidirg blood sample collection, age. breed, sex, and geographic location was recorded for each horse. Data were analysed, using multivariable logistic regression. Results-Horses of 37 breeds from 81 of Ohio's 88 counties were included in the study population There were 481 females, 133 moles, and 442 geldings ranging in age from 3 months to 27 years; 48% were 5.6 years old More than 53% of samples were seropositive for antibodies to S neurona. A gender or breed effect on seroprevalence was not identified. There was a significant effect of age (P ≤ 0.0001; with older horses more likely to be affected), and of location (statistical and extension districts; P - 0.02 and P - 0 03, respectively) on seroprevalence. Location effects appeared to be correlated to the number of days with temperatures below freezing (P < 0.05). Clinical Implications-The high seroprevalence of antibodies to S neurona found in the sample popula tion emphasizes the importance of examining CSF for S neurons-specific antibodies when establishing a diagnosis of egume protozoal myeloencephalitis.