Anytime veterinarians talk about breeding the problem mare, it always develops into a lively, animated discussion. The Table Topic on Breeding the Problem Mare was no different at the 2009 American Association of Equine Practitioners (AAEP) Convention in early December.

The audience was asked to list items for discussion, and many difficult-to-treat causes of infertility were addressed, including the cause and treatment of anovulatory follicles, management of mares with an incompetent cervix, successful yeast infection treatment, and biofilm and how it affects equine reproduction.

Anovulatory follicles are a broad term given to abnormalities of ovulation that result in an egg remaining trapped in the follicular cavity and not entering the oviduct, the site of fertilization. Anovulatory follicles are a menace to veterinarians and mare owners because the problem cannot be predicted and once it occurs, there is no method for inducing that particular follicle to ovulate.

Mares with the condition develop a normal-appearing dominant follicle on ultrasonography during estrus, exhibit classic signs of heat when presented to the stallion, but the follicle does not ovulate even after repeated treatment with an ovulatory agent such as hCG or deslorelin