The majority of domestic sport horse breeders are not as well versed in Thoroughbred bloodlines as their Thoroughbred racehorse breeder counterparts. I know I am not, but I have found that once I gained an understanding of the history of our sport horse breeds and their bloodlines, that knowledge dramatically altered not only the way I viewed our North American breeds, but also the practice of breeding itself.
Because the racehorse, particularly the Thoroughbred, is such an important portion of sport aptitude and historically is such an essential portion of our best-performed North American sport horses (see Part IV and Appendix E ), we should at least have a basic knowledge of our uniquely North American Thoroughbred. How else will we be able to use the marvelous resource of our domestic Thoroughbred to our advantage in our sport-horse breeding programs if we don’t comprehend its important bloodlines for our goals?
In researching our North American Thoroughbred I discovered the most valuable strains to make dominant for my personal sport success, and in addition, I got the answer to some nagging questions that were in my mind from my warmblood-breeding era. For instance, I often wondered why there were not more American lines in the new ‘international horse.’ The answer was, first of all, there are more of them than I recognized; second, the international sport horse is a very new concept, and there was very little inter-breeding between continents until the twentieth century, and thirdly, our Thoroughbred horse was banned from international breeding for the first half of the twentieth century by the British Jockey Club. Yes, it is true, and this full first part of the book will give you the story on this event, but more important to us as breeders, it will explain to you exactly what it was about the American Thoroughbred that made it such as threat to Anglo breeding establishment.
“No horse or mare can, after this date, be considered as eligible for admission unless it can be traced without flaw on both sire’s and dam’s side of the pedigree to horses and mares themselves already accepted in the earlier volumes of the book”(GSB 1913; emphasis mine).
The book referred to in the above quotation is the General Stud Book (Weatherby’s) of the English Thoroughbred, and the English Jockey Club passed this rule unanimously in May of 1913. This regulation, popularly known as the ‘Jersey Act,’ slammed the door shut on the majority of American Thoroughbreds that could be allowed admission in the English Stud Book. England is the creator of the Thoroughbred breed, and therefore they control the qualifications of the breed. For the first forty years of its existence, the American Thoroughbred had been accepted into the GSB (General Stud Book), but in 1913 it was refused entry on the basis that it had ‘impure’ bloodlines. According to the English Jockey Club, there were certain bloodlines in the American Thoroughbred that were ‘flawed’.
The American horses were still allowed to race in England, but they could not breed there or anywhere else and have their stock accepted into the General Stud Book; this ruling diminished their worth instantly. That was not the half of it, for it was because of this regulation the American Thoroughbred became a pariah in every country that raised or raced Thoroughbreds, because none of a country’s stock containing American lines would be eligible for the General Stud Book, making them of significantly less commercial value. For admission into the English studbook a horse had to meet their qualifications, but as it has turned out the English Jockey Club standards are not static; they can be and have been adjusted by political policies over the years. Our American Thoroughbred met the standards to be called ‘Thoroughbred’ from 1868 until 1913—so what occurred to change its status?
A lot of stupid laws and regulations get passed every year in every country—in Thoroughbred racing history this particular rule had far-reaching consequences, not just for the American breeder; it eventually hurt England’s and Ireland’s own interests. The real shame of this law is that it remained in force until 1949—that’s thirty-six years (read more on the Jersey Act in Appendix A).
However, there is a flip side not apparent at the time, an unforeseen result of this isolation: the American Thoroughbred over time became very strong in its uniquely American lines, because its best lines were forced to stay at home, and it turned out that those very ‘flawed’ bloodlines carried something extremely precious for sport performance, which would have been diluted without the reinforcement that resulted from the close breeding this segregation imposed. So ultimately the rule meant to harm the American breeder and our Thoroughbred Industry—and make no mistake, that was its intent— nonetheless was in the end a factor in our Thoroughbred becoming the most valuable in the world.