SYDNEY (AP) — Prominent trainer Gai Waterhouse has been fined $5,500 for failing to report the condition and treatment of a horse at the center of an ugly spat involving some of the biggest names in Australian horse racing.

Waterhouse and owner John Singleton were charged by Racing New South Wales after More Joyous finished second-last in a Group One race at Sydney on April 27.

Singleton fired Waterhouse as the trainer as he believed her bookmaker son Tom Waterhouse was informed of problems with the horse when he was not. Singleton, who confronted the trainer at the track in front of television cameras, was earlier fined $15,000 for conduct prejudicial to racing's image.

Racing NSW stewards on Monday ruled that Waterhouse should have reported the horse had been treated with antibiotics.