Effects of multiple GnRH analogue (deslorelin acetate) implants on cyclic mares

Abstract

The equine practitioner commonly receives requests to manage the estrous cycle in performance mares. These requests stem from complaints of less than desirable performance or problem behaviors related to the estrous cycle. Unwanted behaviors or poor performance may be truly related to the different phases of the estrous cycle or they may be behaviors that either resemble some sexually receptive behavior or problems that are ascribed to estrus but have no relationship to the estrous cycle. The approach to these cases involves working with owners, trainers, and caretakers to precisely define and then document daily changes in behavior or performance. The veterinarian should start with a complete history and physical examination and then document the reproductive events in the mare. Finally, working together, the owners/trainers and the veterinarian must establish parallelism between behavior and ovarian events, institute a treatment protocol, and then verify the efficacy of that treatment and management regime.