Last Updated on July 27, 2020 by Allison Price

Breeding horses for most owners can be challenging as it requires extreme planning. The horses are usually bought as an investment and expected to be successful as a sire at this stage. Many promising stallion prospects are unable to pass on their competitive edge. This makes breeding a lot riskier. Thus, many horse enthusiasts do not prefer this type of earning income. Producing a foal from a mare is very exciting but there are many points to consider.

Basic Knowledge of Breeding

Breeders should know the basic knowledge of breeding. If you are new to this job, it would be better to seek professional help with mating and foaling from a stud. You can also check some articles about horse breeding, so you may be able to educate yourself about this.

Essentials for Breeding

We need to also know what are the essentials needed for breeding.  You need to prepare breeding costs and other unexpected expenses.  Breeding horses do not come cheap.

Know your Responsibilities

Breeders should know their responsibilities before and after breeding. Ask your self if you are ready to start this job. Breeding is never an easy task, so if you’re having doubts, you better back out now.

Know your Horses

You should know the right mare and stallion you will use before breeding. Your goal is to produce a foal with qualities like its mother, or even better. Always consider the mare’s genetics, performance quality, temperament, age, and health. Also, consider the stallion on what he brings to the table. Breeding process, live cover or artificial insemination, is something you need to think.

Three Ways to Breed a Horse

There are three different ways a breeder can breed their horses. These are field breeding, live cover, and artificial insemination. Let us all discuss the advantage and disadvantages of these breeding.

Field Breeding

Field Breeding is also known as pasture breeding. It is the safest and best way to breed your horses as it comes naturally. Field breeding means you turn the stallion in with the mare that is in heat during the breeding season.


Field breeding has higher percentage of conception. Breeders report a conception rate of more than 90% success. If the stallion has more than two mares present, then he has more opportunities to breed. Both horses can court, and either can start to contact.


The safety of both horses is usually at stake during this breeding process. This is because they can become aggressive in the ongoing courtship process. Since horses are usually involved in the dynamics of a herd, they might be then intimidated. Sometimes, they get ignored by dominant mares.

Live Cover

Live cover breeding is a stallion mounting a mare, inserts his male member and ejaculates. Live cover happens naturally or it is usually handled by in-house breeding.


All the sperm of the stallion is then deposited in the mare, so there are higher rates of pregnancy. Live cover encourages genetic variety within the breed. Live cover is the perfect option for breeding if the mare is healthy and responds to the process.


Live cover is usually more dangerous to the stallion, the broodmare, and handlers. There is no way to be sure that the stallion actually ejaculates into the mare. Getting the two horses together can be a challenge both schedule-wise and temperament-wise.

Artificial Insemination (AI)

Artificial Insemination is the process of introducing semen from a donor horse to a mare. This is usually done when mare is in estrus. Semen is then inserted to mare other than sexual intercourse to achieve pregnancy. Insemination techniques have been usually refined to make AI an excellent reproductive choice.


AI reduces risk of disease transmission. Stallions breed more mares since one ejaculate can be then split into several doses. Samples can be usually transported worldwide. They use frozen semen, offering mare owners more choices in selecting a stallion. We can cut the travel for the mare as semen is then shipped to the mare’s home facility. They can add extenders and antibiotics to semen that will improve stallions’ fertility. Most importantly, use of AI decreases the risk of injury to the mare, stallion, and personnel


Some breeding organization needs live cover for registration. This includes the Jockey Club for Thoroughbreds. AI techniques need more hands-on management, expertise, and equipment. It also needs increased involvement by a veterinarian. There is a possibility of a decreased genetic pool if few stallions are then bred to large numbers of mares.

Ideal Mare’s Characteristics in Breeding

Mares should be healthy. Before starting on any breeding, it is important to make sure your mares’ general health is at its peak. This would include yearly vaccinations, a dental check-up and deworming. Weigh it up. It is important that your mare is in good body condition for breeding. Also, she should not be too heavy. Mares that carry excess weight may have trouble cycling and falling pregnant. Mares should be in light condition, with a body score of 2.5/5. This allows you to have the mare on a rising plane of nutrition. This improves her condition while waiting to be then bred.

Stallions for Breeding Purposes

Stallions should not be over fat nor should they be underweight. Stallions carrying excess fat may also have increased fat deposits within their scrotum. This may insulate the testes and increase in temperature. This may affect semen production and quality. Also, the fertility rate of a stallion must be high and they must be then vaccinated and dewormed.

Breeding Season for Horses

Mares usually do not undergo heat cycles throughout the winter and early spring. Some mares do have a cycle during the year. In winter, a mare’s reproductive system goes into a rest period. This phase is usually known as anoestrus. After winter inactivity, the cycle usually begins again in spring. The horse’s normal breeding season is from May to August. This is when the highest rates of pregnancy are likely to occur.


How many mares can a stallion breed in a day?

If a stallion is usually used for field breeding, it can mate a lot more than two or three times a day.

When can a stallion start breeding?

Few stallions are then used as stud before two years of age. Most stallions get full reproductive capacity at around three years of age. Most stallions begin to produce sperm as early as 12 to 14 months. But, most stallions are at least 15 months or older before they can have a successful breed.

Can you breed a two year old mare?

After their yearling year, it is okay for well managed domestic mares to start breeding. A two year old filly may have slower milk production than that of older maiden mares. Milk production is strong within a day or so after the foal is born.

How old will the Mares stop breeding?

The mares are usually past their reproductive period as they hit the age of 15 to 16. Sometimes, on rare scenarios, it last until their 20’s.

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!