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What does it take to breed a successful racehorse? with Robert Speers (Speers Bloodstock)

Updated: Sep 9, 2021

Racehorse breeding is the process whereby a stallion (male horse) and mare (female horse) mate to give birth to a foal. When looking at a horse’s pedigree, you may have noticed there is always a sire and a dam listed. During the breeding process, the male horse is called the sire, and in the act of fertilisation and parenthood, the female horse is the dam. In the case of a racehorse, the stallion and mare involved must be thoroughbred so that they can register the offspring as a thoroughbred racehorse.

The idea behind breeding is to have two horses mate that are likely to produce a successful progeny (offspring). Although there is no guarantee that the offspring will be successful, or even make it to the racecourse, analysis of bloodlines and statistics lend predictability to breeding outcomes. Specific horses are chosen to remove any potential weaknesses in the bloodline, hoping to pass on prizewinning qualities and characteristics to the foal. But it is rarely that simple… It is estimated that only 6% of racehorses earn enough money during their racing career to cover their expenses, with a large proportion of horses winning no significant money. Although the cost of the feed and veterinary care etc is the same for almost any horse, it’s the stallion fees that vary most. In Europe at the moment, these fees can vary from £1,000 to £250,000, so if you choose to breed with a horse that has a high nomination fee, be prepared to struggle to earn that money back.

Now, let’s take a more in-depth look at what exactly happens during the breeding process, and how breeders choose which horses to breed with.

What Breeding methods are there?

Regarding thoroughbreds, there is only one, the stallion must "live cover" a broodmare for the offspring to be registered as a thoroughbred racehorse. The Jockey Club prevents any horses bred via artificial insemination or embryo transfer to be registered, despite technological advances in recent years. Live covering, as many of you may be aware, is the natural method of mating. This process can occur naturally in a field, but mostly results from in-hand breeding. In-hand breeding involves selecting the two horses you want to mate, restraining both in a controlled environment, and then allowing them to breed. The mare is examined before and after meaning it offers less risk than pasture breeding, and the mating process is scheduled to meet the supply/demands of trainers. It also allows you to select the horses which you would like to breed, allowing specific characteristics/qualities to be identified, hoping they will be passed on to the foal.

I spoke to Robert Speers, Bloodstock Manager to Mr. Ibrahim Arachi and consultant to Al Asayl Bloodstock. He said: “The process of breeding a mare would see her visit the stallion at a stallion stud once the vet has checked her. This is to make sure that she's well in season and ready to ovulate. A mare has a 21-day cycle and is covered around day 19 of that cycle if all is normal. Once the mare has ovulated and gone out of season, she is scanned at 16 days post covering to see if she is in foal.”

Two horses being introduced in the Breeding Barn

Why does the stallion have to “live cover” the mare?

Jockey Club rules state that for a foal to be registered as a thoroughbred racehorse, the mating process must’ve involved “live covering” as explained above. There are several reasons they don't allow artificial insemination with racehorses including:

· The quality of the horses could be affected if the process involved inferior mares as this dilutes the gene pool and creates inferior offspring. Such rules ensure all horses are of excellent quality and there is no risk of reducing the potential quality of any foals.

· Diversification could also be affected if the breeding pool is limited. This would mean that fewer different bloodlines are available, and as a result, if certain bloodlines dominate, diversification is decreased.

· Most breeders like the traditional way of doing things. Artificial Insemination doesn’t have any worldly benefits and so rules were implemented to keep it the “old way”.

· Artificial Insemination allows for a larger number of mares to be impregnated in a shorter space of time. Though this may sound good, increased supply would cause the stud’s cost to be reduced to balance the demand.

Keeping the breeding where it’s needed using the traditional method helps to avoid any of these potentially devastating knock-on effects. Demand is kept to a premium, the stud fee is kept reasonable for both breeder and trainer, and it maintains the quality of the gene pool.

How do you choose the right stallion to breed with?

I asked Robert for some more information regarding this. He said: “Choosing the right stallion for your mare comes down to several things, including:

· Your price/budget

· How does the stallion suit on pedigree? (it's important to make sure that the stallion and mares’ pedigrees match well)

· What distance did the stallion race over, and does that suit your mare?

· What are you trying to breed? If you're trying to breed a sprinter and your mare was fast, then you need to use a fast stallion.

· Do the mare and stallion match in terms of conformation and physical appearance? It's important to consider this as a small mare might want a stallion slightly bigger than her.

· A stallion should have a good race record, be sound and have a good temperament. I try to avoid breeding from stallions that have had soundness issues, wind operations or horses known to have bled, as these can all be hereditary and passed on.”

It is important to consider all the factors as they can all impact the foal equally. Once you’ve decided on a fee and type of horse to breed, you can begin looking at the pedigree, race records and background info such as temperament to determine which stallion is best to breed with. A horse with good conformation would have a shorter back and longer neck. Horses with these characteristics usually have the best athletic ability, as it means the horse can move easier and more quickly. The horse is more likely to withstand the demands of training as a result.

But it’s not as simple as just considering the above. Racehorse breeding is very much a genetic lottery, you just have to be lucky enough to match the numbers and breed a winner.

In what ways can breeding a racehorse go wrong?

The breeding is just the start of a long process (if all goes well) from the mare giving birth to a foal, to the foal hitting the racetrack. A lot of effort goes into ensuring the young horse is well maintained, from keeping on top of any veterinary needs, to simply getting the horse to grow and produce a nice coat. This will pay dividends in the future as it helps to avoid injury and prevents the horse from being rushed in its upbringing.

Robert said: “Breeding an unsuccessful racehorse is what most people do; most horses are not much good. To breed a good horse, you have to be lucky but also use your knowledge to send your mare to the stallion that suits it best. If the mare ends up in foal, carry's the foal to term with no problems, and gives birth, then you have to rear the foal, paying huge attention to detail with feed, farrier, vet etc. Whether you train the horse yourself or sell it on, keep the odds in your favour by doing things the right way to avoid injury. As a stud farm manager, the rearing of a foal and looking after young stock in the right way is a huge part of a horse's future career.”

Many people make the same mistakes when breeding a racehorse. The select few are just in it for the money and have a "get rich quick" mentality. New breeders forget that those who are successful didn't become so overnight, and so will attempt to cut corners to produce more foals and get money in whilst they can. Alternatively, if they've taken an early hit, then they are more likely to rush out before putting their expensive lessons to good use.

Countless people will rush in and breed with the mindset that if they don't want the foal, they can just sell it. Planning the breeding to be commercially viable is important, and just because a stallion is good for breeding to race, it doesn't mean they are necessarily a good choice at producing foals purely just to sell on. Just because something looks “proven" on paper, it doesn't mean it will be… Looking for information on good bloodlines to cross is worthwhile, however, rushing in to breed with a specific horse just because the offspring have performed well is a dangerous game. It is important to consider the conformation of the horse, size and also class/distance raced.

An example of a horses' pedigree, in this case, FRANKEL

The “proof” is in the pudding?

As we’ve already established, nothing is guaranteed with breeding, but breeders have determined a few things that are worth noting. First, if horses appear in the pedigree of a horse more than once through a different son or daughter, then the quality of the racehorse is likely to be higher. They call this line-breeding and it’s the most popular form of reproduction in racehorses. The genetic variance is reduced with them being from the same bloodline, which in turn increases the number of desired traits. A stallion passes on his Y-chromosomes to his sons and his X-chromosomes to his daughters, which is why line-breeding on a horse via a son or daughter is particularly successful.

There is also a variation of line-breeding called pattern breeding. This involves repeating a pattern of ancestors found in the mare with a similar family found in the stallion's pedigree. This increases the likelihood of passing on useful characteristics by having several influential ancestors in the same section of lineage.

Despite all of this, you can still never guarantee if a horse will be good, or even enjoy racing until it gallops. The pedigree might suggest it will be top class, and this means there is a higher chance that it will be, but it’s never a dead cert. As Robert said: “You can't see the horse's will to win, how game it is or how much it wants to race. On the whole, well-bred, athletic young horses by good stallions with good conformation tend to be the best horses on the track. However, what is exciting about our sport is that plenty of other horses that have conformation issues or cost less to produce still win races. That’s what keeps the dream alive for all breeders, big and small.”

An idea of the structure of a horse and what features to look for

So is there a “best time” to breed a racehorse?

I wanted to know whether the time of year or age of the horse had any impact on horse breeding. Robert said: “Most mares and stallions start their breeding careers around the same age (4 or 5 years old) though some stallions retire younger. Mares have an 11 month gestation period so they’re designed to have a foal every year. Most stallions, if fit and well, can cover mares until their early 20s, same with mares, who in their lifetime can have up to 14/15 foals. The breeding season in this part of the world runs from early February to around the middle of June, so thoroughbreds here are usually born between January and May. Mares in the wild would always breed in the springtime, so we try to stick with nature because of pleasant weather and good grass for nutrition and milk production. Having a foal born in winter wouldn’t be very beneficial.”

So that’s that. Hopefully that answers a lot of questions people have with regards to racehorse breeding, I certainly learned a lot throughout writing this article. I’d just like to thank Robert again for co-operating with me on this piece, and for providing us with such insightful information on the topic in hand.

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