Comparative analysis of various technologies of breedings of horses

Abstract The article presents the results of studies to assess the effect of natural mating and artificial insemination with frozen semen on the duration of the service period in mares. The research is aimed at determining the optimal technology to improve the reproductive qualities of horses. The pregnancy rate of 716 breeding mares in 1093 estrus cycles after natural mating (NM) (534 mares, 850 cycles) or artificial insemination with frozen semen (AIfs) (182 mares, 243 cycles) at the foal heat and three subsequent cycles, at the end of the year, per one cycle and the level of pregnancy lost were calculated. The results showed that in the NM program the most part of mares (>80 %) were covered at the first cycle with the lowest level of pregnancy (44.7 %) and the highest level of embryonic losses (12.6 %). In subsequent cycles, the efficiency of NM significantly (p<0.001) increased (up to 80–90 % pregnancy rate at the fourth cycle), and the percentage of embryonic death decreased to 0 %. In the AIfs group of mares, obviously with more careful monitoring of uterus condition after foaling, only 30 % of them were selected for insemination with frozen semen at the foal heat with results similar to the pregnancy level of NM at the first cycle (43–52 %). It was concluded that NM and AIfs at the foal heat in mares are advisable and can provide the normal pregnancy rate if a qualified control of the genital tract condition is ensured after parturition.