London - Queen Elizabeth II's racehorse Estimate has been stripped of its second-place finish in this year's Gold Cup after a positive drugs test, the British Horseracing Authority (BHA) ruled on Thursday.
But although Estimate's post-race sample contained the banned substance morphine, it was the result of contaminated feed, so the Queen's trainer Michael Stoute avoided a financial penalty.
Another horse trained by Stoute also tested positive for morphine at Royal Ascot and had its ninth-place finish in the Buckingham Palace Stakes annulled.
"The horses have been disqualified from the races in question. No financial penalty has been imposed upon the trainer," the BHA said in a statement on Twitter.
The BHA was satisfied that all reasonable steps had been taken to avoid wrongdoing, but the rules of racing state that horses that test positive for prohibited substances must be disqualified from the relevant races.
Estimate narrowly lost to Leading Light in this year's Gold Cup.
It had won the Gold Cup the previous year, making the Queen the first reigning monarch to own a winner of the prestigious race.