When examining the chronically infertile mare, it’s important to remember that the uterus is not an organ suspended in space–it must be viewed as one part in a complex system. Anything affecting the animal, no matter how remote, can have an effect on the reproductive system, according to Michelle LeBlanc, DVM, Dipl. ACT, a practitioner with Rood & Riddle Equine Hospital. LeBlanc presented on diagnostics and case management of these mares at the Florida Association of Equine Practitioners (FAEP) Promoting Excellence Symposium, held Sept. 27-29, 2007, at the Atlantis resort on Paradise Island, the Bahamas.

Diagnosing these mares begins with a physical exam of the entire animal.

"Your physical exam and taking a good history will give you the answer about 60% of the time," LeBlanc said. The veterinarian should consider factors such as the mare’s age, condition, and whether she’s sound. If that checks out, then scrutinize the reproductive system more closely.

If she notes anything abnormal during the vaginal exam of the infertile mare, LeBlanc advocates running both cytology (examination of the cells) and cultures. In a recent study, LeBlanc and Tom Riddle, DVM, looked at the diagnostics used on 970 Thoroughbred mares in Central Kentucky. Of these mares, 55% of those with reduced fertility would have remained undiagnosed without cytology to catch inflammation, and 17% would have remained undiagnosed without culture to catch infections