Should You Breed Your Mare?

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Every spring, mare owners get excited about choosing a stallion for their mare, but many decisions need to be made before selecting the stud and breeding the mare. 

By Tania Millen, BSc, MJ

“Breeding is not for the faint of heart,” says Lisa Longtin. She owns Merrington Warmbloods in Kindersley, Saskatchewan and has been breeding warmblood horses for the dressage and hunter rings for 25 years. “When things go well, it’s great. But there are so many things that can go wrong.”

Before deciding to breed a mare, it’s important to acknowledge why you’re breeding, what you’re trying to produce, and what the plan is for the foal. Once that’s clear, consider the rationale for breeding a specific mare, the mare’s ability to become pregnant and carry a foal, your budget, the actual breeding process and logistics, plus the risks. 

Why breed?

Determining why you want to produce a foal is an important first step. 

“With the current economic situation and drastic increase in the unwanted horse population, creating a new equine life needs to be carefully considered,” writes Dr. Megan Williams, DVM, of Brandon Equine Medical Centre, Florida, in her article Considerations When Breeding Your Mare.

Canada’s National Farm Animal Care Council (NFACC) concurs, stating that many welfare problems can be prevented through responsible breeding, which is defined at noted below in their 2013 Code of Practice for the Care and Handling of Equines.

Responsible breeding:

  • is purposeful rather than accidental or indiscriminate;
  • is managed by owners and handlers that are trained and knowledgeable;
  • involves careful selection of a mare and sire that are proven in their field, have good conformation and temperament, are healthy and free from known hereditary conditions that will impact on the welfare of the offspring;
  • is based on comprehensive criteria for breeding, including past reproductive performance, age, size of the sire and mare;
  • produces offspring that has a known market or purpose.

Everyone has different reasons for breeding. Commercial breeders are producing quality foals and young stock for sale. Heritage breeders are committed to developing or maintaining specific genetics and lines. Owners with exceptionally talented mares may want to pass along their athletic genes. Some riders believe it’s less expensive to breed a top-quality foal than purchase a high-performance youngster. Other riders get immense satisfaction in producing and showing a homebred foal. Regardless, acknowledging your rationale for breeding in the first place will help determine which mare is suitable and what stallions to consider.

What are your breeding goals?

Knowing the ideal traits that you’re trying to produce will help determine the best dam and sire plus ensure your expectations and breeding budget are appropriate.

The NFACC provides useful guidance, stating “Established breeders generally follow a specific breeding program producing quality offspring for a specific market.” That means breeders hoping to produce foals for a specific sport choose dams and sires that were competitive in that sport, had long careers, and remained sound.

For example, Longtin is producing horses for amateur riders, so her foals need to have a temperament suitable for those buyers.

“I really value a horse that is a willing work partner and has a great work ethic,” Longtin says. “You’re able to progress and they meet you at the gate and they’re happy.”

What are your plans for the foal?

Producing and raising a foal is a multi-year commitment so it’s worth envisioning how the future may play out. Before breeding, make plans for handling, weaning, housing, and training the foal. If the foal will be raised and trained, who will do the training and at what age? If the foal will be sold, when will it be marketed and what’s the expected sales price? What will you do if the foal doesn’t meet expectations or is injured? Nobody has a crystal ball so it’s worth considering various scenarios to ensure you’re prepared for all possibilities.

Create a breeding budget

Dr. Daniel Jou says that a ballpark cost for a veterinarian to get a mare pregnant — excluding the cost of semen and provided there are no complications — is between $1,000 and $3,000. He’s a reproductive specialist and the owner of Jou Equine Veterinary Services in Wellesley, Ontario. Jou says that the cost depends on how much veterinary work is required, whether the mare will be transported and housed elsewhere, plus how the mare will be bred (live cover, artificial insemination using fresh cooled or frozen semen, or more complex methods such as embryo transfer).

Longtin has hauled mares to a regional stallion for breeding without veterinary involvement and got them pregnant for less than $1,000. With other mares she’s spent $3,000 to $6,000 trying to get them pregnant with veterinarian involvement. “That’s money you never get back,” she says, “regardless of whether the mare becomes pregnant or not.”

Accordingly, it’s worth creating a realistic budget before breeding and considering whether the foal you’re producing will be worth the eventual cost. 

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Lisa Longtin of Merrington Warmbloods produces horses to be willing partners for amateur riders. Two of the foals she’s bred are the filly DandelionMW (by Dauphin out of Confidante), sold as a dressage prospect (above); and Sesta Elemento MW (by Schwarzenegger out of Confidante) sold through the CWHBA Fall Classic Sale in 2021 and being developed as a hunter (below). Photos courtesy of Lisa Longtin

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Choose the mare

“If you love everything about a mare and know what should make her offspring better, then jump in, educate yourself, and do your best,” Longtin says. “Hopefully, things turn out well. The thing that saddens me is to see people who have an ill-tempered mare or one that they don’t like riding because [she’s] difficult, [and] deciding to breed her.”

“The mares have such a big influence on the personality of foals. They really do,” says Longtin. “And I think people with ill-mannered or ill-tempered mares need to think hard about having a foal from that mare, because that personality is more than likely going to come through in the foal.”

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The mare should have a sociable character, a calm temperament, rideability, and willingness to work. She is genetically responsible for 50 percent of the foal, but many breeders believe her influence is greater since in the formative months after birth she has a major influence on her offspring’s personality. Photo: iStock/Kerrick

Dr. Jou suggests breeding the mare with the best genetics for the foal that you want to produce, whether that’s a potential Olympic horse or an everyday companion.

With advances in technology, it’s not unusual to breed mares in their mid-20s, provided they are reproductively sound — something Longtin thinks is lacking in current breeding programs.

“The great flaw with breeding horses is that we don’t breed horses to be reproductively sound,” says Longtin. “We breed them for their athletic prowess — conformation and that sort of thing — but we don’t look at their breeding soundness.”

That may not be top of mind for one-off breeders, but conformation, soundness, genetics, and a trainable mind are worthy considerations. It’s also worth choosing a mare that has a high likelihood of producing a sound, healthy foal and that won’t be passing along genetic diseases.

“I like a low maintenance mare,” Longtin says. “I want a nice mare for sport but I don’t want one that’s colicky, or that’s a hard keeper, or that has medical problems. I want a really nice sound, healthy mare.”

Related: Equine Embryo Transfer

Assess the mare’s breeding health

“The capability of a mare to produce a foal rides on a large number of factors other than simple exposure to the stallion,” writes Dr. Williams. She advises that breeders get to know their mare’s heat cycle and have a reproductive health exam prior to breeding, to ensure the uterus is healthy.

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To increase the chances of a successful result, your veterinarian should perform a breeding soundness exam on the mare prior to breeding season. The exam can identify potential problems to be addressed prior to breeding season. Photo: iStock/Purple Queue

“Two or three ultrasounds and a swab sample culture are a good start for assessing breeding suitability,” says Dr. Jou. Conducting ultrasounds to confirm ovary health and follicle size will help the veterinarian decide when the mare is most receptive. Plus, that knowledge will improve the likelihood that the mare will become pregnant when she’s actually bred.

But the mare’s overall health is imperative, too. According to the NFACC, reproductive efficiency is maximized by maintaining broodmares at a body condition score (BSC) of 5 to 7 throughout breeding, gestation, and lactation. Mares that are too thin (BCS less than 5) at the beginning of the breeding season or at foaling have lower conception and pregnancy rates.

Related: The High Risk Mare

Choose the stallion

Dr. Jou advises spending as much as you can afford on the stud fee. 

“It’s the cheapest part of breeding, considering all the time you spend raising them, training them, and going to shows,” he says. “The stud fee is very, very small compared to the overall cost of what goes into producing a horse and the difference it makes can be enormous.”

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To help choose the right stallion to complement her, evaluate your mare objectively to assess her strengths and weaknesses. Photo: iStock/Kent Weakley

He says that matching compatible mare and stallion genetics increases the likelihood of a good quality foal to seven times out of ten. Breeders who don’t know the mare’s or stallion’s genetics, or don’t plan a compatible match, tend to produce good quality foals only once or twice out of ten breedings.

Acknowledge the risks

Like everything with horses, breeding has risks.

“I’ve had foals almost every year with some exceptions,” says Longtin. “There’s a certain acceptable loss percentage [of foals] with breeders, but we’ve been pretty lucky. Last spring we had our first abortion and we’ve had a mare that’s not very fertile, plus two mares who reabsorbed their pregnancies in the fall. Other than that, it’s been pretty good.”

Dr. Jou says that it typically takes two or three breeding attempts each year for a mare to become pregnant, with 40 to 60 percent of mares becoming pregnant from those efforts. Once a pregnancy is confirmed, mares will produce a healthy foal approximately 80 percent of the time.

Ultimately, choosing to breed a mare in the hopes of producing a specific foal can a challenging and expensive activity.

“It's probably cheaper in the long run to buy a young horse from somebody else,” says Longtin. “Breeding is always a gamble and I think you have to be prepared to lose whatever you put into it. If you’re comfortable with that, then go ahead and try to breed your mare.”

Related: Effects of Longer Day Length on Pregnant Mares

Enter the breeding game with eyes wide open. Breeding is a complicated endeavour and being well informed is particularly important for first-time breeders. Be sure to understand the myriad details involved and evaluate all the costs and commitments, risks and rewards of this long-term project. If, after careful consideration you determine that breeding your mare is realistic and responsible, and your chances of success are high, you can more confidently start turning your vision of a frolicking foal in your pasture next spring into a reality. 

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Photo: Shutterstock/Callipso88

Related: Collecting Colostrum for your Foal

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Main Photo: Dreamstime/Jamie Hooper