Horse Breeders are now starting to look to the new breeding season, so I thought that it made sense for this week’s addition to be about the Mare’s Reproductive Cycle, System and Vital Breeding Hormones. As briefly touched on before, Horses are no doubt one of the hardest mammals to breed with successfully. Of course is it important to have a good stallion to breed with, but having a good broodmare is like gold! Mares have 11 month gestation periods, so it is not exactly a quick turnover if something goes wrong during pregnancy, nor is it cheap or easy in effort or emotional involvement. That is why a lot of Horse Breeders and their Vets are very pedantic about getting everything about the process right from their end of things.
The Reproductive Cycle and System of a mare are very similar to that of a human, but there are some significant differences. Mares tend to have 21-23 day cycles (depending on the individual mare). During this cycle, if mares have been covered on the 19 or 20th day (or both), they are generally then tested for pregnancy on day 17 of the following cycle. Prior to day 17 of their cycle, Mares are considered to be in anoestrus. Then starting from day 17 is oestrus.
The Mare’s Reproductive System is that similar to a human’s that I won’t bore you all with part and decriptions, however I will list the parts here as the Ovaries, the Fallopian Tubes, the Uterus, the Cervix, the Vagina, the Vestibule, the Vulva, the Pituitary Gland and the Mammary Glands. The Vestibule is just a smaller part of the Vulva, and is where the Vagina begins from the outside of the Mare.
Quite a few medications are used by Breeders at different times of a mare’s cycle to assist in having the right hormones at the right time for reproduction. A few key ones include: Regumate – contains the progesterone hormone that stops cycling when it is not needed, Prostaglandin – helps to start the mare cycling again, Gentam – for antibiotic fever and Oxytocin – to assist in creating contractions when substances need to be flushed from the Mare’s Uterus. All of these medications should be prescribed and used with a Vet’s approval.
Breeding with Mares can be a complex process, however if understood correctly by Breeders and their Vets, beautiful and healthy foals can be born and raised into the next generation of horses. Hopefully this brief summary has helped some of you to learn about how vital Broodmares are to a Breeding Program.
Feature Image courtesy of RG Morgans.
– Skye Pickering Dip. Horse Business Management