Millions of racing fans who followed the recovery of Grand National favourite McKelvey on television after his near fatal injury in the race last year were left devastated after the horse died in yesterday's gruelling race.
A spokeswoman for Aintree racecourse said: "Regrettably, McKelvey sustained an injury after unseating his rider at the 20th fence and was humanely put to sleep."
The animal rights groups Animal Aid had warned before the race that McKelvey was at particular risk in the steeplechase. Spokesman Andrew Tyler said McKelvey, who damaged a tendon while coming second in last year's race, could not have possibly recovered from such an injury sufficiently, and would not be fit enough after a year without racing.
Aintree officials said, however, that all horses entered for the race had to pass a veterinary test, and a spokeswoman for Peter Bowen, the horse's trainer, said the McKelvey had been fit.
"This is a race even a fit and healthy horse struggles to finish, never mind a horse that suffered such an injury just a year ago," Mr Tyler said. "It's the most gruelling, lethal race in the world. I hope the BBC shows the public that an event it sponsors, and millions of people bet on, leads to the deaths of horses. As an animal lover, it is a very distressing race to watch. I think it should be stopped. The obstacles are intentionally difficult."
McKelvey's death brings the number of horses to die in this year's meet to three. On Friday, Time to Sell and In the High Grass died after falls in the Topham Chase. According to Animal Aid, 174 horses have now died in horse races in the UK since March last year.
Since 1991, 51 horses have died at the Aintree meeting, although only one jockey has been killed. Improvements to the course were made in 1989 after two horses died after failing to clear Becher's Brook.
The RSPCA said the race had been made safer following negotiations with the racing authorities. Improvements included reducing the numbers of horses, adapting fences, as well as enforcing stricter entry requirements and moving the crowd further back to reduce distractions.
McKelvey's recovery was followed by the sports presenter Clare Balding for the BBC's The One Show. Viewers were also able to log on to a "stable cam" set up by the BBC at the horse's stables in Pembrokeshire.
Earlier this year the horse's trainer, Peter Bowen, said: "McKelvey has come back from his tendon injury and he looks as good as he has ever been, so we are hopeful of another good run at Aintree in April again this year."
Speaking to Clare Balding, the trainer added: "Ever since I was a five year old I've wanted to train the winner of the National."
A spokeswoman for Aintree said yesterday: "Yesterday's race was won by Comply Or Die, a victory which left bookmakers facing one of the biggest payouts in the race's 160-year history.
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