Embryo transfer in subfertile mares.

This study explored the effectiveness of embryo transfer in mares that have been subfertile for at least two years. The research found that 50% of embryos were recovered, and of the 9 embryos transferred, 44% resulted in pregnancy, suggesting a low efficiency in using subfertile mares for embryo transfer.

Overview of the Study

• The key focus of this study was to investigate the efficacy of embryo transfer in subfertile mares, defined here as mares that have not been able to conceive for at least two years. The purpose was to evaluate the viability of using subfertile mares in an embryo transfer program, contributing to a more comprehensive understanding of equine reproduction.

Methodology

• Four subfertile mares were selected as donors for the embryo transfer program. The researchers analyzed the embryo recovery rate, which was the percentage of embryos retrieved from the mares after ovulation.
• The researchers successfully recovered 50% of embryos, although this rate varied significantly from 0% to 100%. Following this, 9 embryos were selected for transfer to determine the potential pregnancy rate.

Results and Conclusion

• The study found that out of 9 embryos transferred, 44% led to successful pregnancies. This indicates that while it is possible for subfertile mares to become pregnant via embryo transfer, the efficiency of this method is relatively low.
• The researchers concluded that 20% of the flushings resulted in pregnancy, suggesting that the conventional methods can be successfully employed with subfertile mares to some extent, but it is likely to be less successful than with fertile mares.

Implication of the Findings

• The results of this study contribute to the understanding of equine reproduction processes and the potential effectiveness of embryo transfer in subfertile mares. This insight is valuable for veterinary clinicians and horse breeders seeking to heighten pregnancy rates in subfertile mares.
• Despite the low efficiency found in this study, embryo transfer could still be considered a possible strategy for achieving pregnancy in subfertile mares, although further investigations are necessary to optimize the process.