Methods for the treatment of twin pregnancy in the mare.

This research studied methods to treat twinned pregnancies in mares, finding that the use of a prostaglandin analogue at less than 35 days of gestation was a notably successful treatment.

Study Objective and Methodology

• The research aimed to study twin pregnancies in mares and identify effective treatment methods to increase the likelihood of live foals. 130 mares carrying twin pregnancies were studied over two breeding seasons.
• For 29 mares, diagnosis involved a single palpable follicle at service and a single pregnancy at 42 days.
• In the second group, 70 mares had twin pregnancies diagnosed by rectal palpation. Five different treatment methods were applied to five subgroups of these mares and the outcomes evaluated.

Study Findings

• Out of the initial group that was carrying twins, only 17 live foals were born, a success rate of 13%. Breeding results for the next season showed that 37% mares produced live foals resulting in an average success rate of 23% in live foal production over two seasons. This suggests that traditional twin pregnancy detection and management strategies can often yield low live foal birth rates.
• Within the 70 mares that received different treatments after diagnosis of twin pregnancy, 28% produced live foals in the same season. In the following season, 61% produced live foals, indicating an average success rate of 46% over two seasons among the treated group.
• The study found that the introduction of a prostaglandin analogue at less than 35 days of gestation was the most effective treatment method and significantly increased the number of live foals born. Prostaglandin analogues work by inducing luteolysis, which can help to reduce the number of fetuses in a case of multiple pregnancies.

Conclusion and Implications

• This study’s findings show that appropriate detection and management of twin pregnancies in mares can improve the chances of live foal births.
• The most effective treatment was the use of a prostaglandin analogue at less than 35 days of gestation. This should be considered when dealing with twin pregnancies in mares to maximize the chances of successful births in subsequent seasons.