Management Strategies Aiming to Improve Horse Welfare Reduce Embryonic Death Rates in Mares.

The research looked at how different management strategies, specifically designed to improve the welfare of horses, could affect pregnancy and early embryonic mortality rates in mares.

The methodology of the research

• The study evaluated breeding records from 1206 Thoroughbred mares over ten breeding seasons that were all housed in a single stallion station facility.
• The mares were divided into two groups, namely Stress and Relax, each of which was subject to a different management strategy.
• The Stress group’s management was conventional, while the Relax group’s management eliminated stall confinement, teasing routines, and decreased the number of mares per group.
• The relaxing of herd stability during the breeding season was also maintained in the Relax group.

Key findings of the study

• Analysis revealed a significant increase in pregnancy success in barren mares from the Relax group as opposed to those from the Stress group. The pregnancy rate in these mares was almost 7% higher than in the Stress group.
• In the case of mares that already had foaled, there was not a significant difference in pregnancy rates between the Stress and Relax groups, with rates only slightly higher in the Relax group.
• The rates of embryonic death (ED) were noticeably higher in both barren and foaling mares in the Stress group compared to the Relax group.
• When comparing the foal heat pregnancy rate, there was no significant difference between the mares in the Stress and Relax groups. Yet, a significant decrease in embryonic death during foal heat was noted in the Relax group.

Conclusions from the study

The study concluded that the Relax group’s management strategies aimed at improving animal welfare, particularly reducing social stress, had a positive effect on reproductive performance in mares. Specific benefits were a reduction in early pregnancy loss and fewer average cycles per successful pregnancy.