My girls have lots of Big Heart blood in their veins. In 1789, an autopsy of Eclipse showed that he had a 14 lb. heart as compared to the average of 6 lb hearts of the time. He had a big heart. Secretariat was found to have a heart over 22 lbs, much higher than the 9 lb. average. In fact, of Secretariat's heart, his autopsy physician, Dr. Thomas Swerczek, said, "We just stood there in stunned silence. We couldn't believe it. The heart was perfect. There were no problems with it. It was just this huge engine." They now believe that big hearts are tied to the female X chromosome. So, you can be a "single copy" or "double copy" mare and if you are a big heart stud, you can pass your X to your children too. If a "double copy" mare is bred to a large-hearted stallion, she will always produce large-heart foals and double copy fillies. Violet is directly related to four of the most famous Big Heart stallions, Princequillo, War Admiral, Blue Larkspur, and Mahmoud. Hailee also has big heart studs, including Moon Deck, Three Bars, Easy Jet, Top Deck, and Leo. Man 'O War was a big-heart stud. The thing with big-heart stallions is that they can only pass their big heart to their daughters. So, often since it takes a crop or two for their big heart gene to express or show itself, thoroughbred stallions will be "sold down river" to the Quarter Horse industry which is why the American Quarter Horse is filled with Big Hearts from their thoroughbred relatives. Man 'O War blessed both breeds with his big-hearted heritage. Among the relatives suspected of having big hearts, my girls have Rock Sand, Count Fleet, Eclipse, Pocahontas, Glencoe, Lexington, Domino, and La Troienne. And they have Audience, daughter of Sir Dixon (the Belmont Stakes Winner) and grand-daughter of Hindoo, the Kentucky Derby winner. She foaled Whisk Broom and in her own racing day, she won the all-important Kentucky Oaks! She is considered a big-hearted gal!! Among the ways she's related to my girls are through Po' Chile for Violet and Sir Bim for Hailee. The photo has a picture of her baby, Whisk Broom. You can read more about the X-Factor at the following links:
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