Horse breeding.


11 Years
Sep 9, 2008
I thought it would be a good idea to start a topic for people who are new[like me:p] to horse breeding and had questions/comments/etc.

How old is too old to breed? Is there any easy way [without a vet] to tell if a mare has been bred before? What tests should you have done before breeding?
Really? I heard 25-ish. But it probably depends on the horse and breed.

It really does. It also depends upond the mares condition, how fast she wastes with out regular exercise. How her past births went. Her dental condition is of great importance. if her teeth are bad she is having a tough time getting nutrition for herself, much less a foal. Our old McCoy Arab mare was under a lot of pressure from Arab stud owners and I put my foot down and tols them to go to heck. I was more concerned with the quality of her life then I was in owning a new McCoy Arab.

Pretty Arab
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She's a great mare and I'd love to breed her, but I also don't want to risk her life or anything.
I would never tell someone else they shouldn't breed their own horse, it's yours, do as you like, but you can probably buy a very nice foal that's already on the ground for less than you can "grow your own". You won't have to wait a year for it, you will know exactly what you are getting, not to mention there is no risk to your beloved mare then. There are so many horses out there that need homes.
A good rule of thumb when wanting to breed a horse, is what faults conformation wise does your horse lack that could be fixed with a good sire. Can you register the foal?
WHY do you want to breed your mare? Can you afford vet care, special innoculations that are needed for mares that are pregnant? And can you afford the extra food that is necessary to have your horse carry to term and to have a healthy foal.
Don't breed your horse if you can't afford vet care, and to have them mare checked for good heat cycles, fertility, and to ensure she doesn't have a common problem with a lot of mares, a minor urine tract infection.
Many mares must be cultured and have a clean bill of health before being allowed to be bred. ALso can you afford mare care, generally it is is charged at where the stallion is while the mare is there, similar to board, but there is a sliding scale if she comes with foal at side, or needs special feeds.

Also don't breed your horse to your friend's unbroke, un trained, non show record, fugly, Kool Kolored stallion/colt. It is well worth the money to pay a little more for a good stallion with a show record. Also don't breed if you can't be sure what color you will get, unless you don't care.. don't breed to the grulla/buckskin/palamino if you are hoping for that color but are breeding him to a mare that will likely only throw, black, bay or chestnut.
Ask yourself WHY you want to breed. And then research, save money, and plan ahead!!
'Don't breed unless mare and stallion are top notch'. We all know that reality is that people are not going to stick to this. Many people have mistaken ideas about making a profit with small scale breeding of average quality horses...underestimate the cost and work involved or feel they can train the youngster despite their lack of experience training.

'Breed just for yourself'. The idea doesn't work out well in reality. Every breeding should be tailored to a specific market, with the stallion and mare chosen to be as appealing as possible to that market. It's amazing the number of 'just for me' babies that wind up in the marketplace in a few months or years. Situations change. If the mare and stallion are not appealing to a market, the owner better resolve himself to put in a lot of work - training MAY make these horses more appealing in the marketplace.

About 'find the stallion that makes up for the mare's faults' (breed 'strong to weak' concept). No guarantee that the trait will wind up as desired. That trait may be more like the mare or more like the stallion. There is nothing guaranteeing a stallion's trait will prevail.

This is (despite old fashioned ideas that 'a good stallion will dominate the mare' or that 'this stallion is high quality, because he has many more dominant genes'(I chuckle whenever I see that statement). Genetics doesn't work that way - it's a 50-50 chance or less, except for some very simple traits, and when a desirable trait actually is created by dozens - or more likely hundreds or even thousands, of genes together (like back length or 'good gaits'), simple mendelian dominance plays less and less.

There's just as much chance that the result will be a collection of traits that don't work well together, or the weaker traits of the mare plus the weaker traits of the stallion.

The more different the mare and stallion are (in that specific trait or in general), also the less related mare and stallion are, the less predictability in what the offspring will be.

One of my most vivid memories in horses, is of the gal who owned a 22 year old mare. The mare was getting weak and unsound behind. Unbeknownst to her, the mare was bred when a stallion got loose at the not-so-great barn where she boarded. She did not realize the mare was in foal until the night the mare gave birth to two stillborn foals.

The barn staff realized something was wrong and called her in. She could not afford emergency vet care. The mare bled to death, but there was evidence of overwhelming infection and insufficient placenta as well.

None of that needed to happen. It was all avoidable. She knew the barn kept several stud colts and that the fencing was very poor. The barn manager SAW the colt catch the mare on more than one occasion, and decided not to tell the gal.

Pregnancies need to be planned, monitored by a vet, and supervised closely by an experienced breeder on site.

Anyone interested in breeding a mare of any age should start out by going to some of the excellent free breedng seminars vets give, and by making a relationship with their nearest equine reproductive vet. A first timer should seriously consider boarding the mare with an experienced breeder who knows what to do, can recognize when something is going wrong, and can get the vet out quick if something goes wrong. Yes, that is expensive. Good breeders charge fairly for their expertise but it is not cheap.

There is an awful lot to learn. And while it may sound 'snobby' or 'mean', for most people, raising a foal is really not a good idea. Most people underestimate what it will take (timewise, skillwise) to break a foal and train it. Sure you could get an easy one, but you also might not. Too, as we all know from doing anything new, the first couple times around we make a lot of mistakes - it's just part of learning.

Of course the other thing is that breeding horses is a very, very tough business. We don't see the foal the breeder had to have put down because of a deformed leg or other genetic disorder. Even if the foal can scamper around, that leg may not hold up a yearling or older. We don't see the dummy foals that breeders spend thousands on to keep alive, often, only to lose them. We don't see the mare the breeder spends several years and thousands of dollars on, just to get her in foal. We just get this idyllic picture of mamma and baby grazing in the grass and frolicking around. In reality, breeding horses - breeding any large animal, is a difficult and demanding job...often with moments of heart ache and tough decisions. It just is not for everyone.

Summary - Issues with choosing to breed - 1.) appropriate facility for foals, ability AND TIME EVERY DAY, to break and train offspring 2.) condition/soundness esp of legs and back/reproductive/work history of mare as well as age 3.) weight of mare 4.) avoiding orphan foals 5.) low fertility in mares 6.) accidental/unknown/unplanned for pregnancies

The first thing is - foals. A foal is a wild animal. It is a wild animal of the worst kind - familiar with you and not particularly afraid of you. Foals run through fences - they cannot be safely put behind the same kind of fencing as adult horses. They require wider doors, bigger stalls, and they tend to be on the bottom of the totem pole in aherd of all-adult horses. They need more room to run and develop than most people have. They must have controlled nutrition or they are going to have growth/metabolic problems. All these factors make it hard for the average horse lover to raise a foal.

The 'don't breed past a certain age' idea.

Reproductive organs age right along with the animal. They just don't work as well in the older animal. Tissues become less flexible, less stretchy, heal slower and simply work less well. For every old mare someone brags they got pregnant, there are a great many more that can't be gotten in foal no matter HOW much money someone expends in vet bills and stallion fees.

Another factor is weight. It's obvious to most people that a starving, thin animal is hard to get bred and carry a healthy foal to term. What is NOT obvious is that overweight mares are much harder to get in foal, and hav special problems carrying a foal to term. Most people don't realize this, but mares must be in condition - not too fat, nor too thin, to increase their chances of getting in foal and carrying a healthy foal to term. Overweight DOES interfere with breeding and pregnancy.

One factor that wasn't mentioned in deciding to breed/not breed was soundness. Being a large heavy animal (yes, this covers minis and ponies too), a mare has to be in rather good physical condition to carry a foal without pain or jeapardizing her own health.

Carrying a foal is hard work, so is birthing and nursing a foal. If you think of human friends who have had a lot of babies, you know each one adds up in how it affects the body. You also know some women have babies easily and carry them easily and some do not. If you think of it as being like running a many month long marathon, that's about right.

A mare's hind quarters, back and stomach (ligaments, muscles) and all of her legs and feet especially, need to be in excellent condition to carry the extra weight.

Injuries and wear and tear over the years can mean a mare really should not be bred. This can happen at any age.

Mares that have foundered/have insulin resistance, Cushings, other medical issues, been worked very hard over the years, that have broken down in the rear ankles, back or stomach ligaments, will suffer an awful lot carrying a foal to term. We have to think not about 'will the foal live to weaning age, if so, then so what', but about what we are putting the mare through. Is she really fit to be bred?

Nor is raising an orphan foal if 'the mare doesn't make it' so very easy. A foal is far better off raised by the mare. Orphan foals tend to have an awful lot of behavioral problems. I know more than one horse lover who has tried to raise an orphan foal after their shouldn't-have-been-bred mare died giving birth. It is fantastically difficult to wind up with a normal, trainable youngster after it is orphaned.

Every mare has a unique life they have led. Some mares will get hurt early on and should never be bred. Some will foal again and again, into their twenties. A much larger number cannot and should not.

The other problem is just the nature of the mare as an animal. It is often said that of all domestic animals the mare has the lowest fertility rate of all. That means they are not always easy to get in foal or to carry a foal to term. That is just a fact of life.

It is not just due to age. With every year a mare is not bred ('left open'), it becomes more difficult to get them in foal.

It also depends on how they are cared for. Mares need reproductive care all their lives -not only a few weeks before breeding. Conformation may mean a mare contaminates her reproductive tract and this has to be dealt with medically during the years the mare is open.

The mare you buy that is accidentally bred before you get her is a special problem. Mares need specialized nutrition for every stage of pregnancy. You won't know if that was done -if it wasn't it can result in serious complications. Mares need to be bred to a stallion that won't result in too big of a foal. Mares need to be in safe turnout situations when pregnant or they can get kicked, or eat plants or get diseases that cause abortion.

Mares who twin need to have one of the fetuses terminated. You won't know if the mare is twinning or not.

The idea of a mare carrying the foal of a stallion of unknown size, with inappropriate medical care, turnout and diet during the pregnancy is something most experienced breeders shudder at. That's why vets advise having any mare you buy tested for pregnancy BEFORE you buy. That's why they often recommend terminating 'whoops' pregnancies.

While a stallion can get loose at any barn, it's the lower-budget barns where stud colts most often go without gelding, where fences and management is most often deficient, and where are found most of the cheaper sale price mares manyof us non-Steven-Speilberg-budget folk buy. That's why we have to be extra careful about buying 'woops' mares.
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