Methods for managing seasonal anestrus and the transitional phase in mares
Subject Areas : clinical veterinary science
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Keywords: Mare, seasonal anestrus, reproductive management, artificial lighting, hormone therapy.,
Abstract :
Seasonal anestrus and transitional periods are key phases in the reproductive cycle of mares, playing an important role in their fertility and reproductive efficiency. This study aims to investigate the physiological mechanisms related to these periods and introduce effective management strategies to stimulate ovarian activity and reduce the duration of reproductive inactivity. The main focus is on the use of artificial lighting and pharmacological interventions, including hormone therapy with GnRH analogs, progesterone, and dopamine antagonists. The results of this study indicate that the precise implementation of therapeutic protocols and appropriate environmental conditions can assist in follicular growth, induce ovulation, and ultimately improve reproductive performance in mares. This study serves as a practical guide for veterinarians and breeders to enhance reproductive management in mares. Mares are among the species whose reproduction occurs during the longer days of the year, with multiple reproductive cycles occurring during the breeding season. Their reproductive activity is significantly influenced by the length of daylight (photoperiod). The reproductive cycle of these animals is divided into four main stages: anestrus (inactive period), spring transitional period, breeding season (including estrus and diestrus), and autumn transitional period. Two key stages in this cycle, seasonal anestrus and the transitional period, have a major impact on fertility productivity and reproductive performance in mares. During the seasonal anestrus, due to the reduction in daylight hours, ovarian activity in mares decreases, and the estrous cycle halts. On the other hand, the transitional phase is a transitional period that shifts mares from anestrus to the breeding season (spring transitional period) or from the breeding season to anestrus (autumn transitional period). These periods, due to hormonal changes and fluctuations in ovarian activity, significantly affect fertility and reproductive health in mares, presenting considerable management challenges due to irregular ovarian activity and the absence of ovulation.
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