Capote euthanized at age 23
 

bloodhorse.com:

Champion Capote, a son of Seattle Slew, was euthanized Aug. 24 at Robert N. Clay's Three Chimneys Farm near Midway, Ky. The 23-year-old pensioned stallion was buried at his home of the past 16 years.

"While his appetite and spirits were remarkably good to his last day, Capote's coordination had declined to the point that he presented a danger to himself and others," said Three Chimneys Farm president Dan Rosenberg. "The spinal cord problems finally became too much for him to deal with, but he lived with that condition for four years without surgery. Capote had a good life."