Dunaden won the 2011 Melbourne Cup and 2012 Caulfield Cup
He also won six races in his native France, including the Group III Prix de Barbeville and had the overall record of 10 wins and 20 placings from 46 starts.
"Dunaden is the horse that got Sheikh Fahad and his family hooked on horseracing," said the sheikh's racing manager David Redvers. "When he won the Melbourne Cup for a young Sheikh Fahad it really opened up the opportunities that horseracing can present. It's a very sad day as he was definitely one of the family."
Sheikh Fahad added: "Dunaden was a horse of a lifetime. Winning the Melbourne Cup is a day I will never forget. He was pure class – consistent, strong and incredibly competitive. Qipco's initial increase in investment in racing is largely down to Dunaden's success. It is a terrible loss."
With his oldest progeny now three year-olds , Dunaden has sired five winners from 20 runners.
"He's made a relatively bright start to his stallion career considering he wasn't terribly fertile and had very limited opportunities," said Redvers.
Simon Sweeting, manager of Overbury Stud added: "It was a huge honour to have stood Dunaden at Overbury Stud. I was delighted to have been involved with him and am very sad to have lost him so early."
