According to popular belief, there is no shrewder kind of wheeler-dealer than a Kentucky horse trader.

But one Kentucky horse trader has found that he and his brethren are innocent lambs compared with some of the powerful men in the French breeding industry.

Wayne Murty, who with two brothers runs an international bloodstock business, learned this lesson when he bought 56 horses for $840,000 a year ago. After an improbable chain of events, Murty now has neither the horses nor his money.

"The French have manipulated this whole thing," Murty said by phone from Paris yesterday. "There's a real stench about it."

Last July Murty encountered the greatest opportunity of his career in the horse business. He learned than an aging French textile magnate, Marcel Boussac had developed his own distinct bloodlines over the years and had guarded them jealously, while breeding 12 winners of the French Derby. His mares represented a genetic treasure trove.

Murty flew to France, entered into negotiations with Boussac's representatives, and finally bought 56 horses for $840,000. His jubilation was short-lived.

Two days later, a bloodstock agent representing a then-unidentified client, tried to buy the horses from Murty. When the Kentuckian declined, the agent told him he never would get his horses out of the country.

Murty assumed that this was an idle threat; other buyers of Boussac horses had no difficulty taking them to far-flung parts of the world. But when Murty started making plans to ship his new acquisitions to the United States, he was stymied immediately. Two officials-Henri Balcn, head of the National Stud, and Jean Romanet, executive director of the French Jockey Club-had refused to sign routine export documents.

Soom Murty learned the reason. Another man wanted the Boussac horses, and he was no ordinary adversary. He was the Aga Khan, the most prominent horse owner in France (with more than 90o thoroughbreds in his worldwide operation), and a man with far-reaching political clout.

The Aga Khan had just donated three stallions to Blanc's National Stud, which might have influenced the decision to deny Murty's horses export documents. But the Aga Khan's influence showed even more clearly when the bulk of Boussac's horses were being sold.

Murty was interested in bidding on these horses, ezpecially the French Derby winner Acamas, whose value as a prospective sire he estimated at more than $6 million. But the head of the syndic , the group in charge of liquidating Boussac's assets, told him that all 144 horses would be sold as a package, and that Acamas would not be allowed to be exported from France. That effectively shut out Murty from buying any of the horses, and the Aga Khan acquired all of them for a bargain $9.5 million.

He then shipped Acamas to Ireland, without any objections from French officials.

But the Aga Khan was not satisfied with those 144 horses; he wanted Murty's too. He offered the sundic $1.4 million for the horses that Murty had already bought. The syndic accepted and Murty took the issue to court.

A bankruptcy court ruled that the syndic was obliged to protect the interest of Boussac's creditors and accept the Aga Khan's bid. Moreover, Murty would have to wait in line with the other creditors to get back the money he had spent; he would get about $440,000 back.

So Murty countered by offering $1.5 million for the horses. The syndic turned him down. The Aga Khan has taken possession of the horses and started breeding the mares.

Murty still is fighting for them. "The Aga Khan has everybody in his pocket," he said, "but we're not giving up. The court may not be able to hear this case for another two years, but these horses would put our breeding program so many years ahead that we're going to go ahead and go the whole route.

"For nine months there's been a complete suppression of news about this in France, but I feel it can't be tucked under the carpet. There's too much interest in it now, not just in the Murty brothers but in the integrity of racing and breeding."