Born in the Sudan, Percy Sykes did his training in London before World War II, and then served in India with the Royal Army Veterinary Corps. Setting up in practice in London after the war, Sykes was drawn into the world of racing through doing horse insurance work with Lloyds of London.
Sykes migrated to Australia in 1951, and established his practice in Sydney. By the end of the decade his clients numbered many leading trainers, most importantly Tommy Smith. Sykes not only treated Smith's horses, but became his close friend and confidant for 30 years. It was Sykes who diagnosed the cause of Tulloch's almost fatal illness. As Tommy Smith said, "only for Percy Sykes, Tulloch would have died”. Almost every top horse in Smith's stable, including Kingston Town, had the benefit of Sykes' treatment. Sykes was one of the first veterinarians in the world to initiate blood testing to monitor how a horse was responding to training, and Smith was among the first trainers to avail himself of this facility.
Sykes also had remarkable success in treating horses for leading trainers such as Jack Green, Bart Cummings and Jack Denham. Robert Sangster frequently sought his advice. For Jack Green he operated successfully on Silver Phantom and brought him back to the track, after that horse appeared to have hopelessly broken down. Baystone was saved by Sykes after breaking his jaw in the barrier, and subsequently went on to win the Melbourne Cup. Igloo, runner-up in the Caulfield and Melbourne Cups, was often quoted as Sykes' greatest success. In 1971 in Perth he broke down completely after shattering sesamoids in both front legs. 22 months later, after treatment by Sykes, he reappeared at Rosehill, winning over 2,000 metres carrying 61.5 kg.
No wonder Sykes was described as “the doctor they call when all hope's lost”.
Sykes was inducted into the Hall of Fame in 2006.