Tratamientos médicos para inhibir el comportamiento sexual en sementales

Abstract

In clinical practice, owners and riders frequently asked for medical treatments to suppress stallion’s sexual behaviour outside of a breeding environment, particularly in training or competition, without permanently losing their reproductive capacity. There are different hormonal treatments on the market that can be used as alternatives to surgical castration, but whose effectiveness, reversibility or side effects may limit their use. Traditionally, continuous progestogen-based treatments have been used, and anti-GnRH vaccines are now becoming more popular due to their more comfortable administration guideline. However, in both cases the subsequent breeding career of these horses must be taken into accountsince their reversibility, especially when used for long periods of time in young animals, is not currently fully assured. The use of GnRH antagonists and agonists have limitations due to the variability of results or/and their high cost. Furthermore, in practice, the use of relaxing or anxiolytic tranquilizers is relatively frequent for this purpose, however,either side-effects or absence of efficacy studies makes their use questionable or contraindicated. In any case, it should be noted that behavioral problems must be evaluated globally and that when choosing a pharmacological agent, possible side effects, as well as national regulations regarding registration for its use in this species and further rules regarding sport horses or “food-producing” animals must be taken into account. This article reviews the major pharmacological agents reported to control sexual behavior in stallions and outlines the most relevant papers, their efficacy, side effects, expected reversibility and possible regulations regarding food-producing and competing animals.