婆罗门
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战斗力 鹅
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注册时间 2011-4-3
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reading is fundamental,lol
An extremely large heart is a trait that occasionally occurs in Thoroughbreds, hypothesized to be linked to a genetic condition, called the "x-factor", passed down in specific inheritance patterns.[138][139][140] The x-factor can be traced to the historic racehorse Eclipse, who was necropsied after his death in 1789. Because Eclipse's heart appeared to be much larger than the hearts of other horses, it was weighed, and found to be 14 pounds (6.4 kg), almost twice the normal weight. Eclipse is believed to have passed the trait on via his daughters, and pedigree research verified that Secretariat traces his dam line to a daughter of Eclipse. Secretariat's success as a broodmare sire has been linked by some to this large heart theory.[138] However, it has not been proven whether the x-factor exists, let alone if it contributes to athletic ability.[141][142] |
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