The two horses had tested positive the banned substance between June 24 and July 14 2018. The anabolic steroid is strictly prohibited from racing competition, and is classified as a “major doping drug”.
The horses were subsequently banned, and their trainers accused. This had been a surprise among the racing community, as the trainers had previously been considered to have good reputations.
Yet, the case has now been deemed “very rare” by experts, after the horses were found to have the drug in their system not due to intentional cheating, but because they had accidentally eaten some old hay, which caused the substance to metabolise in their stomachs.
The discovery was made after analysis by the horse racing laboratory in Verrières-le-Buisson (Essonne).
The hay in question was isolated, and a link drawn directly to the hoses who tested positive. The horse trainers have now been exonerated, and the horses reinstated.
Pierre-André Jay, commissioner for the racing federation of the Centre-Est region, said: “We had a theory [about the hay] that had been put forward by a Swiss vet, after the horses had tested positive. But it was only a theory.
“Now, we have been able to establish a causal link, clear the names of the professionals, and demonstrate this educational evidence.”
In a bid to explain how the old hay could have been accidentally provided for the horses, he said: “We are a small rural race track. We try to work with local materials, and we buy hay from local farmers. It was grain hay - oats and barley, I think - but it had been stored for some time.”
Dr Hélène Bourguignon, manager of biology at French racetrack authority La Fédération Nationale des Courses Hippiques, said: “In the hay, we found the precursor of boldenone, which is called boldione. These are bacteria in the digestive tract of the horse, which allowed [the drug's] metabolisation.”
Compensation is now due to be paid to the horse trainers in question, “with the help of civil liability insurance”, Mr Jay confirmed.
He added that the sport was tightly regulated, and applied “extreme rigour” towards any “banned performance drug”.
He said: “Racecourses are [among] the most tested in the world, because owners and betters involve money [in the sport].”
According to Dr Bourguignon, of 300,000 tests every year, "just 0.23% are positive, and in 80% of these cases, it is not clear fraud".
She said: "It is perhaps due to horse mismanagement, such as a horse that is racing too soon after a health treatment, or accidental use of a saddle that still has traces of medicine on it.”
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