Serum hepatitis in two brood mares

Abstract

Serum hepatitis is the most common cause of acute hepatic failure in horses, and has been associated with the administration of biologics of equine origin, especially tetanus antitoxin. Lactating mares appear to be at a higher risk for development of serum hepatitis than are other horses; however, this may only reflect the common practice of administering tetanus antitoxin to mares at the time of parturition. Although serum hepatitis usually is associated with severe hepatic failure and death, less severe or atypical manifestations of the disease may be possible.