Uterus unicornis in two mares.

The research article is about two unique cases of a congenital condition in horses, where one uterine horn is absent. The study follows two different mares over 20 years on commercial breeding farms, assessing breeding and fertility despite the lack of one uterine horn.

Background and Aim of The Study

• The researchers came across two unusual instances of a congenital defect in mares over a span of two decades. This condition involves the absence of one uterine horn, and in one case, an ovary was also missing. The aim of the study was to further investigate these notable cases and understand the fertility implications for the mares.

Research Methodology

• Both mares were subjected to routine examinations prior to breeding, yielding the initial discovery of the congenital malformation.
• Physical examination techniques and ultrasonic tests were used to diagnose and track the reproductive anatomy and activity of the mares.
• The mares’ ovulation and pregnancy were monitored closely to assess the impact of the condition.

Key Findings

• Both mares managed to get pregnant despite the absence of one uterine horn.
• The absence of the uterine horn did not hinder the regularity of the mares’ oestrus cycles.
• In the mare missing an ovary and uterine horn, the mare became pregnant during a cycle where she ovulated from the existing right ovary.
• The other mare’s first four ovulations from her left ovary didn’t result in a pregnancy, but a pregnancy did occur when she ovulated from both the right and left ovaries at the same time.

Conclusion and Recommendations

• The researchers concluded that one uterine horn and ovary might be sufficient for a mare to become pregnant and deliver a healthy foal.
• They recommend that if the absence of a uterine horn is suspected, multiple examinations should be conducted, possibly by more than one experienced clinician.
• They also suggest delaying mating until ovulation is expected from the ovary on the same side as the existing uterine horn to increase the chances of a successful pregnancy.

A shortage of additional information or follow-up on the two mares means further studies would be valuable. This research contributes to a broader understanding of equine fertility and the potential for successful pregnancies despite the absence of a uterine horn and/or ovary.