Trainer Symon Wilde has been fined $15,000 after pleading guilty to presenting a horse to race with a prohibited substance in its system.

Trainer Symon Wilde has been fined $15,000 over a positive swab returned by a horse in his care which won at Warrnambool in December.

Dexamethasone, a short-acting corticosteroid, was detected in a post-race urine sample taken from Florida Pearl after she won a benchmark-64 race on December 27.

Wilde pleaded guilty to bringing a horse to race when a prohibited substance was detected in its system, and the Racing Appeals and Disciplinary Board issued the fine on Thursday.

Florida Pearl has been disqualified from her win.