Secretariat, the legendary racehorse, was retired from racing at the end of 1973 after a spectacular career that included winning the Triple Crown and setting several track records. After retirement, he stood at stud at Claiborne Farm in Kentucky

. In the fall of 1989, Secretariat developed laminitis, a painful and debilitating hoof condition. Despite treatment, his condition did not improve, and he was euthanized on October 4, 1989, at the age of 19

. Secretariat was buried whole at Claiborne Farm, a rare honor for a racehorse, and his gravesite has become a place of homage for fans

. At the time of his death, veterinarians noted Secretariat had an exceptionally large heart, estimated around 22 pounds, about 2.5 times the size of an average horse's heart. This trait is sometimes linked to a genetic "x-factor" believed to contribute to extraordinary athletic ability

. In summary, Secretariat passed away in 1989 due to laminitis after a celebrated racing and breeding career, and he remains an iconic figure in horse racing history.