Rationale and efficacy of sexual desire stimulation in mares under anaphrodisia

Data from the literature regarding the objectivity of clinical and hormonal methods of diagnosing disorders of the gonads are contradictory, because they do not always accurately reflect the state of the course of folliculo-luteogenesis. At the same time, the relationship between clinical and endocrine indicators is still insufficiently clarified, which does not allow for the development of a justified use of drugs that accelerate the manifestation of sexual hunting in mares. In this regard, our further studies were aimed at studying the dependence of hormonal indicators on the size, shape and consistency of the gonads and determining the effectiveness of stimulation of sexual hunting with prostaglandin F 2α drugs. Before conducting the experiment, it was taken into account that exogenous prostaglandin F-2 alpha has both luteolytic properties - causes lysis of the corpus luteum, and stimulating properties - affects the release of gonadotropin hormones (FSH, LH) by the hypothalamus and pituitary gland, which leads to an acceleration of the manifestation of phenomena arousal stage of the sexual cycle. From the data presented in the article, it can be seen that after the use of estrophan sexual desire was found in a larger number of animals than when bioestrophan was administered and in the control. It was observed that the effectiveness of bioestrophan compared to estrophan was lower according to some parameters: 29% of animals showed less desire for sex, its duration was 1.5 days longer (8.2±1.6 vs. 6.7±0.6), and fertilization is 19% lower. The reaction of the animals to the administration of the drugs in terms of the period from administration to the manifestation of potential libido (desire with clear signs) was almost the same (7.0±1.8 and 7.3±1.2 days). The effectiveness of prostaglandin F-2 alpha preparations, applied to mares with anaphrodisiacs to stimulate the onset of the arousal stage of the sexual cycle, depends on the value of IPRYA (the value of the integral indicator of the size of mare's ovaries), which characterizes the activity of the gonads and their refractoriness to exogenous prostaglandins. With a large value of IPRYA - 14–18 cm, compared to the control, the introduction of estrophan and bioestrophan increased the number of mares that showed sexual desire by 47.5 and 27%, accelerated the onset of sexual hunting by 9 and 8 days, contributed to an increase in fertilization by 43 and 30%. Based on the above, the PI of mare's ovaries can be used to clarify the diagnosis - hypofunction and persistence of the corpus luteum of the gonads. Key words: sexual cycle, sexual desire, exogenous prostaglandin F-2 alpha, anaphrodisia, infertility, mares.