Can A Horse Breed With A Pony?

You know a horse when you see one, and you probably recognize a pony when you see one, but understanding the difference between the two terms might be more of a challenge. What is the difference between a horse and a pony, and can they reproduce with one another?

Can a horse breed with a pony? Horses and ponies are the same species, so yes – they can breed with one another. As is the case when breeding any two animals that have a significant difference in size, care must be taken when deciding to breed your equines.

Keep reading for more information on the difference between horses and ponies and the factors to take into consideration when thinking about breeding the two.

Breeding Horses & Ponies: Are They The Same Species

Horses and ponies are the same species; both members of the family Equus caballus. The difference between the two all comes down to size.

A “pony” is any horse that is shorter than 14.3 hands high, while the term “horse” is used when 14.3 hands high or taller. This means that ponies are horses, just shorter ones. 

Many people believe that ponies are simply young horses, but this isn’t true. A baby horse is called a foal. If the foal is a male, you can call him a colt. If the foal is a female, you can call her a filly. Horses are not considered to be fully grown until they are around 4-6 years of age, depending on the breed.

This means that a horse may not even carry the label of “pony” until they’ve reached their mature height. At this point, the breeder, or owner, will be able to measure the horse and determine whether they are over or under 14.3 hands.

Of course, if both parents are significantly under 14.3 hands, the breeder may assume with a great degree of confidence that the foal will also be a pony – just as with animals of other species, the young will inherit their physical (and behavioral) traits from their ancestors.

While the height difference between a pony and a horse can be very small (in terms of a 14.2 hh pony and a 15 hh horse), it can also be a very wide spectrum. Miniature horses are one of the smallest equine breeds, reaching an average of 34-38 inches at the withers. Compare this with a large draft horse, which can reach up to 19 hh on average (76 inches at the withers), you can see that there can be an immense gap between a smaller pony and a larger horse.

Breeding Horses With Ponies: Size Difference Considerations

Because there is such a wide range of sizes in horses, there are a few considerations to make when deciding whether to breed a pony to a horse (or vice versa).

If you are wanting to breed a 14.1 hh pony with a 14.3 or 15 hh horse, the difference in height (and therefore label) really does not carry any significance.

The difference here would be 2-3 inches, which is negligible. Male horses tend to be larger than female horses on average anyway, so a difference of a handful of inches, or even a couple of hands, does not need to be a factor to consider unless your mare can only accommodate a smaller foal. 

Breeding: Stallion (horse) x Mare (pony)

Attempting to breed a taller stallion with a shorter mare can present a couple of different challenges – one related to the breeding itself, and the other has to do with the size of the foal.

If you are considering breeding a 14 hh mare with a 16.2 hh stallion, you should consult a veterinarian to determine whether the mating itself can potentially cause injury to your mare. The weight will matter here more than the height – if your mare is a stocky Quarter Horse and your stallion is a Thoroughbred with a lean and light build, there is less of a chance of injury than if you have a lean Arabian mare and a draft-cross stallion.

If the weight difference between a bigger stallion and a smaller mare is significant, you will want to consider using artificial insemination for breeding.

The other consideration to take is with the delivery of the foal. There are differing opinions on this. One is that the uterus of a mare is like a fishbowl – in other words, the foal will only grow as large as the uterus can accommodate. There have been multiple studies in this area, one where full Shire embryos were implanted into Shetland mares.

Remarkably, the mares did not typically have trouble with delivery, as the foals only grew so large – though regardless of the birth weight, the foals grew to be the size of full Shires. You may consider this good news, however, smaller ponies in general, tend to have a higher rate of birth complications, including late-term miscarriage and dystocia. The best thing to do here is consult with your mare’s veterinarian before deciding what you are going to do.

Breeding: Stallion (pony) x Mare (horse)

You may be thinking breeding a smaller stallion to a larger mare is the safer option, and you’re probably right – but this route is also paved with a couple of inherent risks.

Obviously, breeding a small stallion to a taller mare will have its own challenges, and artificial insemination is probably the way you will need to go here. That said, there are some farmers that have had success in placing the larger mare at the bottom of a hill or trench, giving the stallion the advantage of height behind her. This will take some manipulation and involvement on your part, but it is an option in order to avoid artificial insemination. 

The second potential concern revolves around the health of the foal. The assumption here would be that the more womb room, the better, but that hasn’t always proven to be true. In the same study with Shires and Shetlands, the reverse breeding was conducted.

Shetland embryos were implanted into Shire mares. While the birthing itself was typically uneventful, the Shetland foals did not thrive. Why this occurred is unknown – the foals may have suffered from developmental abnormalities due to the extra uterine room, or they may have been overwhelmed by the Shire’s milk which is different in both volume and composition to that of a smaller pony.

Either way, the outcome was not good for the babies. Now, this is clearly an extreme example – if you are wondering if you can breed your larger mare to your smaller stallion, you likely don’t have a Shetland and a Shire. That said, just because there is more room in the uterus does not mean there are no risks involved.

Breeding Horses With Ponies May Not Accomplish Your Goal

Asking yourself what your goal is in breeding your pony with your horse will help in the decision of whether or not to go through with it. Many people who want to breed a smaller horse to a larger one want a foal that is either taller than one of the parents or shorter.

For example, you may have an athletic and agreeable show mare, but at 17 hh she may be too tall for you to comfortably ride. On the other hand, you may have an excellent barrel racing prospect, but at 14 hh she’s simply too small for you.

In either situation, you may be tempted to breed her with either a shorter or taller stallion to get a horse of comparable physical and behavioral tendencies but of a more appropriate size for your needs. The fact is, though, breeding for size often backfires.

There are countless stories of breeders selecting stallions for size, and they end up with a too-tall or too-short foal. Taller plus shorter does not necessarily equal “medium.” You might cross a 15 hh mare with a 15 hh stallion and get offspring that matures to 16.2 hh.

You may also breed a 16 hh mare with a 17 hh stallion and get offspring that is 15.2 hh at maturity. Breeding for size is truly a gamble. If this is your goal, your best bet is to select a stallion who has a proven record of producing foals of a consistent size. This route tends to produce the best results.

So When Should You Breed Your Pony With Your Horse?

You understand the risks, and you understand that you really can’t accurately breed for size. So when is it a good decision to breed your pony with your horse? If your vet has given his or her blessing to breed your mare with your selected (shorter or taller) stallion, and you have two parents with lovely personalities, go ahead and breed them.

While you may not be successful if breeding for size, you have a much higher chance of the offspring inheriting the parents’ temperament traits. And as we all know, a horse with a great personality is worth its weight in gold.

You can read more of my recent horse breed articles here!