A rule to ensure racehorses do not enter the human food chain in Great Britain has been brought in.
From the British Horseracing Authority, it means thoroughbreds cannot go to abattoirs to be slaughtered for food, in exchange for money.
This summer, a Panorama investigation found 4,000 former racehorses had been killed at the slaughterhouse in Great Britain and Ireland since 2019.
One of them shown in the programme, Vyta Du Roc, raced at the Cheltenham Festival and had won at the track.
BHA director of equine health and welfare James Given said changes needed to be made.
“The transporting of horses to an abattoir to be sold for consumption should not, in my view, be classed as euthanasia and is not an approach that we should tolerate in our sport, which is why a rule preventing this practice is a positive step," he said.
"I am confident that most British trainers and owners agree with me on this and already observe this principle.”
All horses entered to run in a race in Britain must be signed out of the human food chain via its passport by January 1, 2022.
From this date, any entry to compete will not be accepted unless it has been declared as not intended for human consumption via the Weatherbys App and horse’s passport.
The rule change was put out to consultation with the racing industry, prior to being approved by the committee and BHA board last month.
“British racing has in place a euthanasia code of practice to aid trainers and owners with end-of-life decisions. The guidance is clear that whenever possible, euthanasia should be performed at home or in suitable surroundings," Given added.
Panorama raised concerns over the way horses were being killed at one of the UK's biggest abattoirs.
Many had faced a journey of more than 350 miles by road and sea and suffered career-ending injuries.
In response to the programme, aired in July, Drury and Sons said they "take great care to maintain high welfare conditions and do not accept any form of animal abuse."
Commenting on the new BHA rule, World Horse Welfare chief executive Roly Owers told BBC Sport : "This is an interesting development but like any change, it needs to avoid unintended consequences.
"Signing horses out of the food chain is not the welfare panacea it might appear and it will be important for the BHA to monitor the impact of this change and to act where necessary.
"Equally this change will make the need for lifetime responsibility and traceability for all former racehorses ever more important as the slaughterhouse will no longer be an outlet.
"And until there is a robust digital equine identification system there is still a risk that some racehorses will be entered into the food chain fraudulently in an underground trade that we know carries grave risks for equine welfare."
