Pass a law that one percent of horse racing prize money is deducted and used for the welfare of racehorses after they are retired from racing in Great Britain and Northern Island
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Most racehorses, not all, can be repurposed to have another life after they finish racing instead of being slaughtered
This often entails an expense and the current charities dedicated to the above struggle for funds, when there is plenty of prize money in the sport.
The would mean all participants in the sport including owners, big and small, trainers, jockeys etc.,would make a very small donation to the welfare of racehorses after they are retired.