TOKYO -- Ferdinand, the 1986 Kentucky Derby winner ridden by Bill Shoemaker and trained by Charlie Whittingham, is dead, the horse's former owner said.

"Ferdinand was disposed of during the last year," Yoshikazu Watanabe said Tuesday. He declined to give further details about the death.

The announcement by Wantabe comes more than a month after the death of 1979 Kentucky Derby winner Spectacular Bid.

Watanabe, a horse dealer, said he gave the aging horse to a friend two years ago after Ferdinand was no longer effective as a stud.

"He was getting old and was in some discomfort," Watanabe said.

The horse then had a stint at a breeding farm. Watanabe refused to identify the friend or the breeding farm.

According to the Japan Race Horse Registry, Ferdinand was taken off its list of thoroughbred studs on Sept. 10, 2002 after being notified by Goshima Farm in northern Japan that he would be leaving the property.

The farm's operator told the registry Ferdinand was no longer appropriate for breeding because of his age and failing health, registry spokesman Taisei Hoshino said. The horse was 19 at the time.

Calls to Goshima Farm went unanswered Tuesday.

Ferdinand, the son of English Triple Crown winner Nijinsky II, entered the 1986 Kentucky Derby with only two wins in nine career starts.

Shoemaker won the Derby for the fourth time aboard Ferdinand with a daring stretch ride, cutting inside for the rail to save strides and winning as a 17-to-1 shot. At 54, Shoemaker became the oldest jockey to win the race.

Ferdinand gave Whittingham, the 73-year-old Hall of Fame trainer, the first of his two Derby victories. Ferdinand finished second in the Preakness and third in the Belmont Stakes.

The following year, Ferdinand won Horse of the Year honors by holding off 1987 Derby winner Alysheba by a nose in the Breeders' Cup Classic at Hollywood Park.

But his racing career declined after that and he returned to his birthplace -- Claiborne Farm in Paris, Ky. -- in 1989 to begin a stud career. His progeny achieved little success and Ferdinand was sold to a Japanese buyer in 1994.

"It was obvious he wasn't going to get the support in this country we thought he should get, so then we sold him to Japan," said Dell Hancock, the spokeswoman for Claiborne Farm. "Certainly they paid a substantial amount for a horse like that. We hoped he would find a niche over there and have success."

Hancock said the daughter of Howard and Elizabeth Keck, Ferdinand's owners during his racing career, asked about the horse's whereabouts earlier this year.

Once a horse is sold, "you can't control things and it's out of your hands," Hancock said.