Deslorelin acetate to induce ovulation in mares

Abstract

The mares are seasonal reproductive animals, being influenced by the changes in the daily relation of luminosity during the year, presenting a greater difficulty in the control of the estrous cycle when compared to the cattle. The use of ovulation inducers can improve reproductive efficiency by synchronizing the time of ovulation and reducing the period of estrus. The objectives of this paper were to evaluate the use of progesterone-device for cow estrous induction and ovulation time in mares using deslorelin acetate as an ovulation inducer. Five mares of reproductive age were used, which had their estrus induced twice each. In one of them it was administered with 750 mg of deslorelin acetate. For estrous induction, a 5mg dose was administered via IM of prostaglandin F2alpha at the D0 and an intravaginal device was inserted, which was removed at D8, and a dose of prostaglandin was administered concomitantly. After removal of the vaginal devices follicular growth was evaluated at 12 / 12h intervals until ovulation. All animals showed estrus behavior. Mares treated with deslorelin acetate had a mean ovulation time of 43.2 ± 6.57 while the untreated group was 84.0 ± 14.70, with a significant difference. It can be concluded that the intra-vaginal device use for cattle induces the manifestation of estrus in mares; The administration of deslorelin acetate anticipates the time of ovulation contributing to a better reproductive management in mares.