LATEST: Acute heart failure has been identified as the cause of the death of Melbourne Cup favourite Admire Rakti in the minutes after the race on Tuesday, Fairfax reported.
Racing Victoria's chief veterinarian Brian Stewart told SEN Radio on Wednesday that an autopsy conducted at the University of Melbourne showed that the Japanese stayer, which dropped back through the field in the latter stages of the race, suffered from ventricular fibrillation.
"The diagnosis is that the horse died of acute heart failure as a result of ventricular fibrillation probably, which is a disorganised heart rhythm which happens very, very rarely in human athletes and in horses and is a consequence of the athletic heart and the rapid heart rate during racing," Dr Stewart said.
"It is very rare but it does occur.
"It's a disruption of the normal electrical conduction through the heart and there can be various sets of circumstances that might set it off.
"Athletes are probably more prone to the syndrome especially those with large hearts and a big capacity to raise the heart rate . . . throwing it into this abnormal rhythm and the heart is unable to supply enough blood for the body."
Seventh-placed Araldo was euthanised after experts determined his injury was too severe for a recovery.
The horse broke its leg after kicking a fence on its way back to its stall.
Seven-year-old Admire Ratki's demise was also a personal tragedy for Zac Purton, who had ridden him to victory at the Caulfield Cup only last month, the Daily Mail Australia reported.
The jockey 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 800 metres to go the horse was not responding and Purton began to have suspicions all was not well.
Purton eased him 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 Ratki's Japanese owner Riichi Kondo was also 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 immediately clear. Speaking shortly afterwards, his trainer Mike Moroney said that the stallion had become distressed by a big flag and run off.
3:30 PM : German horse Protectionist has won the 2014 Melbourne Cup but the race has been marred with the tragic death of the Japanese favourite.
Trained by Andreas Wohler and ridden perfectly by English jockey Ryan Moore, the five-year-old burst to the lead inside the final 200m to win running away.
Nine-year-old English stayer Red Cadeaux was runner-up for the third time, with Whot Shot Thebarman third.
But the victory has been tinged with sadness with news that pre-race favourite Admire Rakti died following the race.
The Japanese horse collapsed in the stalls after the race.
The top weight officially finished last.
Reports emerged soon after the race that Admire Rakti collapsed in its stall, with Racing Victoria chief steward Terry Bailey confirming afterwards that it had died, the ABC reported.
Seventh-placed Araldo has also injured broken leg after kicking a fence on its way back to its stall.
The Mike Moroney-trained horse took fright on the way back to the mounting yard.
Araldo reportedly broke the cannon bone in its hind leg.
Vets were working on the horse but its injuries were described as 'life-threatening' according to the Daily Telegraph.
Nine reported Araldo was taken to Werribee Veterinary Hospital with the suspected broken leg.
Japanese visitor Admire Rakti started favourite after winning the Caulfield Cup, but wilted to finish last after being up with the leaders early in the race.
The well-supported Lucia Valentina was always well back and failed to run out the 3200m.
Moore said the horse had run the race 'very easy'.
"He's a very good horse.''
Moore said the horse had an excellent track record.
Moore jetted back into Melbourne, determined to silence Australian critics by adding the time-honoured Melbourne Cup (3200m) to his world-wide Group One victories.
Punters had been burned by Moore's last two Cup rides - the Luca Cumani-trained Mount Athos, who got lost mid-race before finishing fifth to Green Moon in 2012, and Dandino, which was also fifth last year behind Fiorente when his tactics were again criticised.
Moore was in the punters' good books recently, however, when he landed the $3 million WS Cox Plate at Moonee Valley, sweeping around the entire field to take out the glamour weight-for-age race on the heavily-backed Aidan O'Brien four-year-old Adelaide.
The 31-year-old, who rode his first race winner over the jumps when he was 16, rides internationally for major racing stables and is considered by many overseas judges to be in the top three riders in the world.
A Melbourne Cup sits nicely with victories in other major races like the Prix de l' Arc de Triomphe, Epsom Oaks and Derby, King George and Queensland Elizabeth Stakes, and many other Group One races around the world.
After landing his first Group One winner at York in 2003, and winning the jockey's title with 182 winners in 2006, Moore was offered the job of replacing champion hoop Kieren Fallon as trainer Sir Michael Stoute's number one rider for his Newmarket stable.
They have since shared in almost 20 Group One wins, even though Moore rides for multiple trainers now.
Rival trainer Ed Dunlop, who has enjoyed great success legging Moore onto his horses, was recently quoted as saying the hoop could ride successfully anywhere in the world.
"I think his great strength is that he doesn't get flustered. A ride at Kempton is a little bit like a ride at Sha Tin for him - even though it's not, of course.
"He doesn't panic, he assesses races very well and, to be honest, he doesn't get overly excited by however big a race it is," said Dunlop, who will send Red Cadeaux around in today's Cup.
"He's strong, he knows where to be in a race, he keeps things as uncomplicated as possible, (and) he makes very few mistakes."
Punters who have jumped on board Protectionist on the strength of its only Australian start - a fast-closing fourth in the Herbert Power Handicap over 2400m at Caulfield on October 11 - were hoping Moore lives up to Dunlop's wraps.
The five-year-old continued to firm in Cup betting overnight
Aussie punters in late rush for Fawkner and Lucia Valentina
2PM: Aussie punters are hoping for an upset in the 2014 Melbourne Cup - putting their money on local horses ahead of the Japanese favourite Admire Rakti.
Fawkner and Lucia Valentina - and Ireland's Mutual Regard were having a late run with the bookies.
According to Sportsbet, Mutual Regard has come in from $11 to $9, while Fawkner has shortened from $8.50 to $7.50 and Lucia Valentina from $7.50 to $7.
Admire Rakti has drifted from $5.50 to $6.
Around 100,000 people have turned out under sunny skies at Flemington today for the 154th running of the Melbourne Cup.
Ten internationals are running in the Cup.
Cavalryman was scratched this morning due to swelling in his leg.
Meanwhile, punters will no doubt drink up to the new that interest rates are on hold.
Zac Purton hoping for a Cup win
Lismore-born jockey Zac Purton is hoping to achieve a lifelong dream with a winning ride in the $6.2 million Melbourne Cup today.
The 31-year-old will ride Japanese stayer and pre-race favourite Admire Rakti ($5) - the same horse he won the Caulfield Cup on last month.
Purton spent his first seven years in Casino on the Northern Rivers and Mt Gambier in South Australia.
He moved around spending time in New Zealand before his family settled on the Mid North Coast at Coffs Harbour.
Purton last rode in the Melbourne Cup in 2009, finishing 12th on the Ian Williams-trained gelding Munsef.
Casino jockey Chris Munce flew the flag for the Northern Rivers when he won the Melbourne Cup in 1998 on Jezabeel.
Scott Seamer, who is based in Federal, completed the double when he took out the 2001 Caulfield and Melbourne Cup on New Zealand stayer Ethereal.
Purton raced in Ballina after his apprenticeship and was successful for three years.
He has already achieved a lot in 2014, becoming the first Australian to win the Hong Kong jockeys championship since 1991.
Purton, who spends most of his time overseas, went to Japan after the Hong Kong season in the hope of securing a Melbourne Cup ride.
"That's why I went there, to specifically get a ride in the Melbourne Cup because I knew they were going to start coming back," Purton told the Coffs Coast Advocate.
"Obviously the timing worked out well, but it's not over yet, we've still got the big one to go hopefully."
Purton decided to pursue his dream of becoming a jockey at the age of 15.
His parents, Phil and Liz, would drive him on a 30km round trip when he started under Trevor Hardy's stables in Coffs Harbour.
He established himself from there in Brisbane forging plenty of fond memories from his time at Eagle Farm and Doomben before touching down overseas in 2007.
He now boasts a healthy bank account living in a four-bedroom apartment in Hong Kong with a live-in housekeeper and personal driver.
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