How Important is the Mare
in Sport Horse Breeding?

It might interest you to know that the mare was the primary focus of Tesio. He structured his breeding program on his broodmares--he seldom stood a stallion at his farm. For his broodmare herd he sought out mares that carried specific bloodlines he was interested in- for instance he chose Catnip, a mare that was low priced, of unimpressive stature, her sire was not popular and worse, she carried the banned American bloodlines. Yes, the American Thoroughbred was banned by the English Jockey Club from 1913 to 1949 (Jersey Act--read all about it in and the unforeseen after effects in Legacy of Lexington.) It was this humble mare, Catnip (pedigree) who became the greatest broodmare of the greatest Thoroughbred breeder: Frederico Tesio. I think we want to understand what made her so special!

What was Tesio thinking in buying a mare like that? And that is just it, he was thinking, long and hard, and far beyond the prejudices and fancies of his day.

Tesio knew a few things others did not. Her sire Spearmint, although a great racer also had poor front legs, so he was avoided as a sire--at least for a while--until it became obvious to all he was a great sire of winners. But Tesio was looking at Spearmint, a son of Carbine, because he carried inbreeding to the mare Brown Bess, which he credited great hind-end impulsion and soundness to. And the previous experts have written that this was why he chose Catnip.

But there is much more to this humble mare. As I mentioned Catnip possessed American Thoroughbred lines, and the American Thoroughbred and ANY horse that carried their lines, which had not been previously accepted in the General Stud Book was not allowed to be registered as Thoroughbred in that era (Jersey Act). Her dam Sibola was an American Thoroughbred brought to England to race before the Jersey Act was in place. And race she did, winning the prestigious One Thousand Guineas. It was the consistent performance of our breed, such as Sibola, that resulted in the anger and outrage that birthed the Jersey Act. But Sibola had already been added to the GSB before the edict slammed down on American racers and so her offspring could be registered in it.

Tesio always looked for classic winners to breed to because he believed in performance as the litmus test for superior genetics--as long as they had pedigrees that carried the lines he wanted. So the Derby winner Spearmint was attractive to him (Brown Bess), and he also desired Sibola for her One Thousand Guinea win.

But Sibola possessed much more that was of interest to Tesio. Her third dam Perfection (pedigree), a daughter of the delicate Leamington, was out of Maiden RH--a daughter of American super horse Lexington RH, out of Kitty Clark RH. The 'RH' stands for Running Horse, which was the pre-Thoroughbred racing breed of America, and it is actually this Running Horse breed that took and continues to hold the world records in true distance racing, records that have never been equaled or broken. For instance, Lexington RH set a four-mile heat racing record that was only beat once, and for only 1/4 of second, and that was done by his grandson Fellowcraft, who is the sire of the great Lady Reel, dam of the sensation Hamburg--see Speed Gene for more on Hamburg. Lexington RH, born in 1850,  he still holds the world stallion record; he was leading sire for sixteen years. The closest modern horse to his sire record is Sadlers Wells, an American Thoroughbred who build a dynasty in England and Ireland and he carries 123 lines of Lexington RH.

Tesio was already familiar with the power for speed and stamina that came this way as his first classic winner Fidia (the horse who put Tesio on the racing map), whose his third dam was inbred 2x2 to Lexington RH daughters--and Catnip had Lexington RH on her damline as well. Obviously, Tesio was not blinded by the English bias, instead he was willing to take true performance excellence wherever he found it.

We can see how right he was also in that the second dam of this mare, Maiden RH (daughter of Lexington RH), is a 7/8 sister to Aerolite RH who is the maternal head of a dynasty that includes Fair Play and his superstar son Man O' War, and she is full sister to the reine-de-course La Henderson. It gets no better than this. There is more of interest here, because Maiden's third dam-sire is a celebrated speed line: Tiger RH, and he is the son of another American foundation: Blackburns Whip RH, who also carries inbreeding to a key mare, Brandon RH through his dam Speckleback RH.

We should not miss how fortunate the design of inbreeding to important mares or daughters of important stallions is, when found especially on the dam-side. Blackburns Whip RH was such a sure source of speed, stamina and perfect gaits that he is found in all three of our American racehorse breeds as well as our saddlehorse breeds--his genetic footprint is massive, on a par with Sir Archy and Janus. But here is the kicker: he was a pacing racehorse, who could also run at the gallop and trot, with remarkable pure and beautiful gaits as well as top speed.

But that is not all, Tesio was also aware that Maiden RH's daughter Perfection is the full sister to a gelding named Parole, and he was the horse that gave the then invincible Isonomy his first defeat, which of course added fuel to fire of indignation the British were stoking concerning the American racers. So it was that Tesio recognized this passed over mare--Catnip--was a genetic gold mine, and history has shown how right he was. 

History has proven how right Tesio's choice to buy this mare was, because the dynasty this mare begot is truly one of the most outstanding in the Thoroughbred breed. Her first daughter Nera di Bicci produced a racing and sport dynasty in Germany through her daughter Nella Da Gubbio, who was by another undervalued sire, Grand Parade. This sire, even while he was a Derby winner, was not thought of well because he the son of another notorious race stealer: the Irish-bred Orby, who had won both the English and Irish Derby, handing the English another humiliation. Why was this such a problem? Not only was Orby bred by the hated Irishman Croker, who was not allowed to even train at Newcastle, but he was out of an American dam! His dam Rhoda B was a daughter of the great Hanover, who carried the top mare Alice Carneal RH 5x6, who is the dam of Lexington RH, and he also had a double of the important Vandal RH 5x5.

Nella da Gubbio, from whom at least five German Derby winners descend, and who is found across the German warmblood sport horses, has the distinction of being descended from the American Running Horse on both sides of her pedigree--she is 3/4 American bred.

Catnip, who was barren for five years before producing Nera di Bicci, proceeded to have more outstanding offspring, including her greatest achievement: Nogara, a great racer herself and a fantastic producer; her best being the incomparable Nearco, whose genetic dynasty has no end.

Obviously, as mentioned Tesio choose his stock and bloodlines with proven performance, no matter what anyone else thought--and we breeders would be wise to follow his example if we want to create something lasting. The American lines not only had blistering speed, but outstanding stamina, proven by heat-racing test, and so it provided the best of both types in one product. And Catnip was no fluke, and it was proven once again by a mare that also slipped into the GSB before the American horse was banned.

Catnip had a contemporary who stayed in England and became the greatest broodmare of her generation on her home soil. This is Lady Josephine, who has a genetic influence that stretches around the globe, especially through her two best daughters: Lady Juror and Mumtaz Mahal.What would modern English breeding be without them and their descendants such as Fair Trial, Sansonnet, Riot, Mumtaz Begum (Nasrullah, Malindi, Rivaz and Sun Princess), and Mah Mahal (Mahmoud and Mah Iran)? They are the bedrock of the modern English Thoroughbred.

Like, Catnip, it was a good thing Lady Josephine was entered into the stud book before the Jersey Act came down, because this pinnacle of English breeding is loaded with American Running Horse lines! When Lady Josephine is written of it is usually her sire Sunridge that is given the credit for her amazing influence. Sunridge is a potent and very good sire, and he is 4x4x4 to the full brothers Rataplan/Stockwell--which makes them 5x5x5 in Lady Josephine, but seldom mentioned is the strong potency coming via the dam, Americus Girl.

I always found it strange that this top broodmare had little attention paid to what her dam gave her. An Irish bred stakes winner, Americus Girl was a daughter of Americus, an imported American Thoroughbred who is inbred 2x2 to full siblings The Nun/Norfolk, who are by Lexington RH out of Novice RH--which makes them 4x4 in Lady Josephine, as you can see they are of about the same genetic weight in her--yet seldom is the mighty Americus mentioned.

Do you think it is just a coincidence that two mares, one with a stud career in Italy, the other in England, with similar power lines coming through the dams, leave the greatest legacy of their time abroad? Here in the States, the daughters of Lexington RH produced greatness also (see Legacy of Lexington for the full story of Lexington RH and his peers, bloodlines proven via the testing of heat-racing produced the bloodlines of both speed and stamina that power racing and sport today).

There is a strong lesson for the breeder in these 'mares of the century' in that, like Tesio, we should look beyond the fancies of our day and discern where true sport ability resides. So let's look at what the other expert's have to say about broodmares.

Understanding your breeding stock's genetic strengths and weaknesses can be the greatest tool you have in your quest for sport horse excellence. Recently a recognition of the power of the mare has become a focus in equine breeding. Although the genetic contribution of both parents is very important, a realization has surfaced that the maternal strength might instead be responsible for more of the foal's attributes. 

The discovery of the large heart gene, a sex-linked trait, was one exciting example of this. Another instance is the advances that have been made into Mitochondrial DNA research, both in humans and equines.

"Around the globe you will see the most successful farm operators active at acquiring quality mares and fillies, they know maternal strength is the pathway to success."(McLean)

It took them quite a while to get to this point of view. In the early days of the stud book mares seldom got a name of their own, more often they carried names like "daughter of Glencoe" identified only in relation to their sire. This had made the study of early Thoroughbred pedigrees difficult. It is worse trying to study Warmblood and Sport Horse lineages--often the mare is just "unknown".

Knowledge in any field comes from the hard work of many people. The advances in equine genetics and breeding are no different. Following are just a few of the "giant's shoulders" we are standing on today.

Frederico Tesio, the father of balanced linebreeding, was an intuitive genius, instinctively he chose broodmares with reserves of nervous energy- this was long before Mitochondrial DNA was ever imagined.

Ken McLean in his Genetic Heritage announced the importance of the dam's x chromosome and he anticipated the future findings in Mitochondrial DNA.

Bruce Lowe attempted to trace and classify those female families that were potent for racing excellence in a number system that is still in use today.

Ellen Parker has developed a 'reine-de-course' list to identify the top producing broodmare lines in the Thoroughbred.

Clive Harper gave us the statistics that have clearly shown that sex balancing pays in his Thoroughbred Breeders' Handbook and then explored the power of the mare in depth in his The Thoroughbred Broodmare Book.

Marianna Haun thrilled us with her The X Factor which traced the large heart gene coming down the x chromosome (see Large Heart Gene).

The above is a partial list, but enough for you to see that all of these ground breakers were ON TO SOMETHING.

What does this mean for the breeders of Sport Horses? Briefly, because equine genetics work the same no matter the breed of horse, we should employ all the knowledge the Thoroughbred Industry is providing. In particular, we should make breeding decisions with an awareness of the strength of superior mare lines- and we should take steps to bring forward this power to our sport foals.

Just as in human research, the equine scientists are able to trace the Mitochondrial DNA back and determine true ancestry. This is a huge help now, and will be even more in the future, when we will be able to fill in those gaps in our sport horse pedigrees. For example, it was discovered by this method, that the General Stud Book (Thoroughbred) had far fewer foundation mares than they originally thought. And it also turned out that some of the foundation mares were recorded several times, but with different names, plus many of the mares were also found to share a common mother. Never before have we had a tool like this-one that can verify bloodlines.

It is well established that proper energy conversion in the cells is essential for good muscle performance. As breeders of horses that we hope will excel in sport we should pay close attention to any new developments in Mitochondrial research.

Evaluation done of the pedigrees in the Thoroughbred Industry revealed that particular pedigree patterns produce either better fillies or colts, and that there also was a difference between good breeding stock (both stallions and mares)when compared to the pedigree design of performance only winners. See Potency Primer page for more on this.

We are living in exciting times for sport horse breeders as every year there seems as if some significant discovery is made concerning sport talent and genetic transmission. For instance, in 2010 the Dr Mims Bower and her research team published their findings that the original foundation mares of the Thoroughbred were not 'Arabian' as long believed, but were what she calls 'native' British and Irish mares- these individuals we know as Running Horse and Irish Hobby mares from the historical records (MacKay-Smith 'Speed and the Thoroughbred'). Then in January of 2012 Dr. Emmiline Hill and her associates further expounded on this, by tracing the 'speed' gene back to "..a British mare about 300 years ago, when local British horse types were the preeminent racing horses, prior to the foundation of the Thoroughbred racehorse." Read the article below.

Dr. Emmiline Hill- speed gene article

This is the same root stock that the American Colonists imported for race and saddle stock--and it was the speed, stamina and athleticism of these early horses that birthed the racehorse breeds of the States. And so it is not surprising that the Irish team determined that the American Quarter Horse carries the speed gene also.

There is an irony in this, in that science is finally catching up with the conclusion of an American equine scholar who determined that speed in the racehorse originates with the Hobby-bred mares of the old racehorse studs of Ireland and England. The scholars I mention are John Wallace who in the 1800s, after fifty years of pedigree research and the establishment of two registries for Trotting racehorses, determined that speed at both the gallop and the trot originated with the pacing bloodlines. What has this to do with the 'speed' gene? Those early racehorse mares were gaited, the Hobby was a gaited breed, which possessed large amounts of stamina as well. The racing trot, with its low straight forward motion developed from the pacers- the elevated showy trot comes from a different source. (See Standardbred Sport Horses for more on this).

A more modern scholar who came to the same conclusions is Alexander MacKay-Smith, he believed that speed originated with the Hobby. They published their work in : Wallace The Horse of America in his Derivation, History and Development 1897 and MacKay-Smith The Colonial Quarter Race Horse 1983 and Speed and the Thoroughbred 2000.

America is blessed with tremendous domestic resources for the sport horse breeder as we have three racehorse breeds (TB, QH, ST) plus a multitude of other light horse breeds that descend from this same root stock: Morgan, Saddlebred, Tennessee Walker and Missouri Fox Trotter. We can capitalize on this science by making an effort to understand the proven mare lines our stock may carry.

Thoroughbred breeders have classified especially potent mares as 'blue hens' and Ellen Parker developed her 'reines-de-course' list and made an indepth study of the female families. With the computer databases available we can also trace our other American breeds back, and therefore find the early transmitters of this sport talent, then locate the modern carriers who possess concentrations of these traits (inbreeding), so we can build them up in our sport stock. With other breeds it may be harder, but not impossible. Here are a few links to stories of outstanding mares or their contribution:

Case Study- The dynasty of Enniskeane Countess

California Chrome --mare power in action

Cavalier Royale --a modern stallion with a powerful dam

Great maternal influences are much harder to find then those coming from stallions. Mares only produce an average of 5-10 foals in their lifetime, compared to a stallion average of 250-500 offspring. So, any mare that has more than a few good progeny is a mare to treasure.

Clive Harper, Thoroughbred pedigree expert, said: "Start with what strength the mare has- always looking very, very closely at the dam line- and build in the complimentary and supplementary names."

One of the most productive practices you can assume in your breeding program is to build up powerful broodmare famiies. When planning a mating for a stallion use your best mare.

California Chrome- Mare Power in Action
Speed and the Standardbred
Speed and the Thoroughbred
Link to Mumtaz Mahal - a Thoroughbred Mare with that is Hard to Ignore.
Cavalier Royale- a modern stallion with a powerful dam
Pocahontas and the Large Heart Gene
The Speed Gene