[The effect of the covering of mares during the postpartum heat on the pregnancy rate].

This research article investigates whether the timing of the mating of mares postpartum affects their pregnancy rate, and notes the potency of inducing oestrus through the administration of a specific drug.

Objective of the Research

• The primary aim of the article was to determine the effects of mating mares during different stages of heat (postpartum) on their pregnancy rates. Mares were divided into three groups; those mated in foal heat (Group I), in the subsequent spontaneous heat (Group II), and in the induced heat (Group III) after the administration of a prostaglandin analogue, Luprostiol, between the 20th and 22nd day postpartum.

Research Methodology

• The study involved mating mares in different stages of heat and monitoring their pregnancy rates. Group I mares, i.e., those covered in foal heat, had a pregnancy rate of 43.9%. On the other hand, Group II mares, those covered in the subsequent spontaneous heat postpartum, had a slightly higher pregnancy rate of 48.6%.
• For Group III, the researchers administered 7.5 mg of the prostaglandin F2 alpha analogue Luprostiol to induce heat. Out of 18 mares in this group, 14 had a foal heat, while 4 did not show a foal heat.
• About 77.8% of the mares (14 out of 18) returned to oestrus 1-8 days after the treatment. Taking into consideration the mares which had shown a foal heat, oestrus was successfully induced in 85.7% of the treated mares. In this group, a pregnancy rate of 50.0% was achieved.

Conclusion and Implications of the Study

• The results pointed out that inducing oestrus by treating mares with prostaglandin 20-22 days postpartum is a viable alternative to natural methods. This method not only increased the success rate of inducing heat but also improved the pregnancy rate to 50%, higher than either of the natural methods.
• This can have crucial implications for the horse breeding industry, providing breeders with a potentially more reliable method of ensuring pregnancies and aiding in better planning and productivity.