Fertility of donor mares following nonsurgical collection of embryos.

The research paper is about an experiment on horse fertility where embryos were non-surgically collected from the mares and later transferred to assess the pregnancy rates, with the ultimate goal of achieving a successful foal birth.

Research Methodology

• The experiment was conducted on 7 Quarter horse mares. The embryos were non-surgically collected from these mares on Day 7 or 8 after ovulation.
• An adapted 30-ml Foley catheter was used to flush the uterine horn that was on the same side as the recent ovulation (ipsilateral) with 500 ml TCM-199, a media commonly used in collecting mammalian embryos, which also contained Hepes buffer.
• Following the extraction, the uteri of the horses were filled with nitrofurazone to reduce the chances of infection that might result from the process.

Results and Observations

• Eleven collections from 7 mares were made which resulted in the retrieval of 9 embryos. Four of these embryos were then transferred non-surgically, leading to the birth of one foal.
• After the collection was carried out, it was observed that the average oestrous cycle lasted for about 22.75 days in 8 instances and 2 prolonged oestrous cycles were reported to be 43 and 59 days long respectively.
• Of the 6 mares that were mated after one or two embryo collections, 5 became pregnant after a single service. The sixth mare conceived during the third oestrus in which she was covered.

This study provides crucial insights into equine fertility and non-invasive embryonic collection techniques. These findings could further improve the efficiency and success rate of equine assisted reproduction, a significant field for horse breeders and the equine industry globally.