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Progesterone therapy in mares with abnormal oestrous cycles
The Veterinary Record
|December 6, 1986
Summary
Progesterone releasing intravaginal devices effectively treated estrous issues in mares. This led to improved ovulation and pregnancy rates in mares experiencing anoestrus or persistent estrus.
Area of Science:
- Veterinary Medicine
- Reproductive Biology
- Equine Science
Background:
- Anoestrus and persistent oestrus are common reproductive challenges in mares.
- These conditions negatively impact breeding efficiency during the covering season.
Purpose of the Study:
- To evaluate the efficacy of a progesterone-releasing intravaginal device in treating anoestrus and persistent oestrus in mares.
- To assess the impact of this treatment on ovulation and pregnancy rates.
Main Methods:
- Two studies were conducted in Holland and France involving 41 mares with reproductive acyclicity.
- Mares were treated with a progesterone-releasing intravaginal device to regulate oestrous cycles.
- Pregnancy rates were determined following induced oestrus and natural covering.
Main Results:
- In the first study (32 mares), 24 mares ovulated and 11 became pregnant after treatment.
- In the second study (9 mares), 8 showed oestrus, 7 ovulated, and 6 became pregnant.
- Overall, 15 of 21 mares treated for anoestrus and 7 of 11 for persistent oestrus were pregnant by the end of the season.
Conclusions:
- Progesterone-releasing intravaginal devices are effective in inducing oestrus and ovulation in mares with acyclic reproductive patterns.
- This treatment significantly improves pregnancy rates in mares suffering from anoestrus or persistent oestrus, enhancing reproductive success in equine breeding programs.
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