Breed-shaping sire Kingmambo has been euthanized at 26 due to the infirmities of old age, Lane's End Farm announced Jan. 20. The influential stallion stood his entire career at the Kentucky operation and was pensioned from stud duty in 2010. Kingmambo will be buried at Lane's End. Regally bred by the Niarchos family's Flaxman Holdings, Kingmambo was by Mr. Prospector out of the champion and two-ti