British Horseracing Authority officials have revealed a post mortem to have ascertained the sudden death of Many Clouds at Cheltenham on Saturday was due to a “severe pulmonary haemorrhage”.
The Hennessy Gold Cup and Grand National winner, who carried the colours of Preston North End owner Trevor Hemmings had just beaten Thistlecrack to claim a second victory in the Cotswold Chase when tragedy struck, as the Oliver Sherwood-trained 10-year-old collapsed shortly after the line.
Although the horse had suffered post-race ataxia in the past, which had seen him over-heat and “wobble” on his feet, Tony Welsh, acting chief veterinary officer for the BHA, said those symptoms “were in no way present or associated with his sad death at Cheltenham”.
Pulmonary haemorrhage through exercise occurs due to a broken blood vessel. No significant underlying health issues were discovered in the autopsy, the BHA said, adding that Many Clouds had worn a heart-rate monitor in training on November 17, 2016 and the data collected on that occasion was within normal parameters in relation to both his heart rate during exercise and his recovery rate after exercise.
Welsh said: “Episodes such as this are rare, and can occur in horses which have no underlying health issues, and amongst all disciplines of sport horses.
“In spite of the rarity of these incidents, as a sport we are determined to do more to understand what causes these symptoms, and whether more can be done to prevent it.
“Several studies have been commissioned, as part of the £32million-plus invested in veterinary science and research by the sport though the Horserace Betting Levy Board (HBLB) since the year 2000. The overall fatality rate in British racing has fallen by a third in this period.”
He added: “Post-race ataxia and similar symptoms are linked to an increase in body temperature after exercise and can be treated by providing the horse with water. It is not uncommon in racehorses or other sport horses.
“Despite some reports following the incident, there is no existing veterinary evidence which links these symptoms with racehorse fatalities, and the post-mortem results have categorically proved that the symptoms exhibited by Many Clouds in the past were in no way present or associated with his sad death at Cheltenham.
“Our thoughts remain with everyone connected to the horse. Any loss of life is regrettable, and we continue to use research, safety measures, regulation and education to reduce fatality rates to as close to zero as possible.