The deaths in Melbourne overshadowed victory for the German-trained Protectionist, who romped away with the biggest winning margin in nearly two decades. They also reignited a bitter debate about the ethical treatment of racing horses.
Jockey Dwayne Dunn and Araldo are tangled in the fence. Photo / AAP / Hamish Blair
Racing Victoria's Head of Veterinary and Equine Welfare Brian Stewart said an autopsy was conducted on Admire Rakti last night at the University of Melbourne and initial results pointed to acute heart failure.
Dr Stewart initially said the horse suffered from :sudden death syndrome", which occurs in just 0.007 per cent of racehorses.
"It's usually one of two things, either through heart rhythm or ruptured blood vessels in that they bleed out internally," he said. "We won't know which until the post mortem is done."
Admire Ratki leads the pack. The horse collapsed soon after crossing the finishing line. Photo / Getty Images
He said an irregular heartbeat which progressed to a condition called ventricular fibrillation - meaning the heart beats in a bad rhythm - was similar to a heart attack.
Ventricular fibrillation of the heart in racehorses could be stress-related and adrenalin could play a role.
He said the death could also have been caused by a by a large blood vessel like the aorta or a major abdominal vessel rupturing then bleeding out internally.
• OPINION: The truth about horse racing
The Coalition for the Protection of Racehorses has called on the racing industry to ban whips following the death of Admire Rakti.
But Dr Stewart said excessive whipping wasn't a factor in the death.
He said Racing Victoria had reviewed footage of the race and the jockey had stopped using the whip when the horse didn't respond. "The jockey immediately put the whip away and relaxed on the horse to ease distress," he told ABC Radio.
"There's no question in this case that the whip played any role whatsoever."
WATCH Protectionist wins Melbourne Cup
Seven-year-old Admire Rakti's demise was also a personal tragedy for jockey Zac Purton, who had ridden him to victory at the Caulfield Cup only last month.
Purton deliberately slowed down when he realised the horse was distressed in the latter stages of the race and they eventually finished last.
"The whole way through the run I thought I'd win," he said. "I didn't think they'd beat me from where I was."
With 800m to go, his mount was not responding and Purton began to have suspicions all was not well.
He eased the horse down and virtually walked him over the line, 25 lengths behind the second-last horse, 200-1 outsider Mr O'Ceirin.
"I didn't know it was as bad as it was. I'm just shattered," he added. "He gave me such a great thrill there at Caulfield."
Admire Rakti's Japanese owner Riichi Kondo was distraught. He was seen outside the stables after the horse's death where the body had been screened off by a green tent.
Staff put up tape and asked the public to move away from the area, saying "there is nothing to see here".
The reason for Araldo's demise was not immediately clear. Trainer Mike Moroney said the stallion had become distressed by a big flag and run off. "It was a freak accident," he said. "They run the Melbourne Cup for 154 years and nothing like that has happened."
An RSPCA spokesman said Admire Rakti's death was a stark reminder of the risks to racehorses.
"Sadly, injury and death are the price some horses pay for our entertainment in a sport that puts intense pressure on animals to perform to the limits of their endurance.''
- Daily Mail Australia
