CHANGES IN SEMEN QUALITY IN THE STALLION FOLLOWING EXPERIMENTAL-INFECTION WITH EQUINE ARTERITIS VIRUS

Two groups of eight stallions each, comprising separate experiments, were inoculated intranasally with equine arteritis virus (EAV) to investigate its effects on semen quality. Semen from each stallion was evaluated two to four times per week on the basis of semen volume, and on sperm concentration, motility and morphology. Significant decreases in motility, concentration and the percentage of normal spermatozoa were detected in the stallions in Experiment 2. A decrease in the percentage of normal spermatozoa was the only significant finding in the stallions in Experiment 1. The changes in semen quality observed in these stallions were considered to have resulted from the combined thermal effects of elevated body temperature and scrotal edema following infection with EAV and were not regarded as virus-specific in nature.