Appropriate Age To Breed A Mare

Last Updated on May 26, 2020 by Allison Price

Breeding a mare and raising a foal is not only a matter of taking them to a stallion. It is not only waiting 11 months and welcome a new member in the four-legged family. We want our foals to be healthy when they come out. Along with the rewards of raising a foal, there are responsibilities and some risks. There are a few things to consider when deciding to breed a mare and raising a healthy foal. This article will help you know if you can still breed your mare or they are already old enough for it. We will also give recommendations on how to know if you can still breed your mare aside from knowing her age.

Mare’s Health

Owners must first pay attention to mare’s general wellness. After that, they can focus on mare’s reproductive health. One most important initial observation is the mare’s Henneke Body Condition Score (BCS). Broodmare’s ideal score should be between 5 and 7 on a scale of 1 to 10. A veterinarian should also perform a breeding soundness exam (BSE) to see if a mare can mate. A rectal palpitation and ultrasound will help the vet know the health of the mare’s uterus and her ovaries. Some mares experience decreased heat cycles as they become older. Exams will detect abnormal structures in the reproductive system.

Veterinarians also suggest a uterine culture and biopsy. A uterine culture will or shows any infection that would decrease a mare’s fertility. A biopsy would show the details of the uterine lining and detects abnormalities.


Breeding horses has evolved. From stallion-meets-mare to mares carrying foals by stallions across the world. Stallions do not need to leave their farm. Producing foals is an investment. Thus, horse owners discovered different ways of producing the ideal offspring.

Live Cover. The stallion penetrates the mare and releases semen straight into the mare’s uterus. This may happen in the pasture or with manual breeding. There are certain breeds that need a live cover, but some accept new methods of producing foals. Sub-fertile mares and stallions can pass their genetics to the next generation. That is through the help of modern technologies

Pasture Breeding. Owners are usually involved with hand breeding. It begins by determining if the mare is in heat. Introduce her to a stallion and observe whether she is responsive to him. If she is, that’s a sign that she is in heat. A veterinarian may also ultrasound her ovaries and observes her follicles. If the stallion has good fertility, breeding may start 48 to 72 hours before ovulation. Mares can breed again in 12 to 24 hours if she has not yet on ovulation and the stallion has low fertility. Handlers bring them to the breeding area once the mare is ready to breed.

Breeding Dummy. The stallion moves up a breeding dummy and ejaculates into an artificial vagina. Handlers add a seminal extender to determine the number of semen in the entire ejaculate. This process uses a heated stage microscope. After getting this information, they divide the semen and extender into doses. If the veterinarian is present, he can administer the semen into the mare.

Freezing Semen. Breeders may chill or freeze the semen if the vet is not on the farm. Frozen semen is viable for 24 to 30 hours after collection. When stored in a liquid nitrogen container, semen is viable for several years. If you consider doing this, you may want to check LN2 Tank Cryogenic Dewar Semen Flask. I recommend this for a durable and cheap storage container.

Equine Artificial Insemination. When the mare is ready for breeding, the handler cleansher perineal area with soap and warm water. After that, the veterinarian inserts a pipette of semen into the mare’s vagina. He must do this with a gloved and lubricated hand. He then relieves the pipette through the cervix and deposits semen in the mare’s uterus. The handler gently removes the pipette and his hand. Semen is viable for 48 hours in the uterus. The mare may go through insemination again if she does not ovulate.

Considerations Before Breeding

If you have had exposure to the equine industry, you may be aware that there are many unwanted horses. They deteriorate in foster homes and rescue farms. Sometimes they are then given for slaughter.

Breeding a quality stallion will cost you a lot of money. There are payments for a veterinarian before and after breeding. Stud farms charge for mare care. If your mare was not able to catch during the first time, you will pay for the extended stay. There will be more vet costs for hormone injections. A small risk of injury is possible which could lead to more vet bills. The cost of raising a young horse from birth to four years is another factor. You could buy an expensive well-trained horse for the same price.

Responsible Breeding

The mare and the stallion used for breeding must be worthy of producing. Breeding poorly conformed mares to a weak stallion is not a responsible way to produce foals. A mare and a stallion must be healthy and able to reproduce. Any broodmare must prove themselves as pleasure or performance horses. They must meet physical and mental desirable traits. These traits must be present to reproduce a quality foal.

Right Age to Breed A Mare

Mares are usually past their reproductive prime when they reach 15 to 16 years old. But there are mares that can still carry and deliver foals in their 20’s. Most of them have many pregnancies before.

Mares can pass their reproductive prime but are fit and competes like a champ to breed. Let her go through the reproductive exams. If she’s cleared with the exams, then your mare can still go through without complications.


Breeding is not easy and may cost you a lot of finances. With determination and your reason for doing so, you may continue with breeding. Always put in mind and consider some important factors because it might be risky for your mare. Gather information and learn about these things. Most importantly, consult a vet and ask for advice. Do this especially when doubtful if your mare can still reproduce healthy foals.

Allison Price
Allison Price

I’m Allison, born and raised in San Diego California, the earliest memory I have with horses was at my grandfather’s farm. I used to sit at the stable as a kid and hang out with my Papa while he was training the horses. When I was invited to watch a horse riding competition, I got so fascinated with riding!