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Trainer Howard Johnson plans to retire after being given a four-year ban by the British Horseracing Authority.
A panel found he showed "a reckless disregard" for rules on horse welfare.
The County Durham trainer admitted running Striking Article eight times after the horse had undergone a palmar neurectomy.
The operation involves severing or removal of leg nerves running to the foot and can leave the horse unaware of any possible pain.
Johnson, 58, claimed he was unaware of the rule stating he should not have run the horse.
He was disqualified for three years with regard to the neurectomy charges, and one year for using anabolic steroids on three other horses.
The trainer was informed last week of the panel's findings following the conclusion of a two-day hearing, but a decision on any penalty was delayed until all the paperwork had been completed.
Johnson indicated when contacted that he had no plans to appeal against the suspension and that he intended to retire from training. He plans to issue a full statement early next week.
He told BBC Sport last week he had done nothing wrong and would stand by that "until his dying day".
Johnson added: "I am not the best man at reading the rules of racing.
"I admitted that the vet de-nerved the horse but I didn't know it was called a neurectomy. The horse was in pain with the state of his feet, and the corns. We relieved the pain of that horse to run eight times, and the horse won three races."
Johnson said the horse would not have pulled up on his final start [at Musselburgh in February 2010] if he had no feeling in his foot.
Striking Article was put down after that race. It was discovered in the post-mortem that the neurectomy had taken place.
Johnson said he was not aware of the rules and did not know that a horse that had been de-nerved was banned from racing on welfare grounds, and because it could affect the safety of the jockey.
When asked during the inquiry for his understanding of the de-nerving operation, Johnson said he believed it would help the horse become sound.
"I just wanted the horse to run...you have to try every corner to get a horse to win a race," he said.
Johnson's most notable wins have come in connection with owner Graham Wylie, most notably with Inglis Drever, winner of three World Hurdles at the Cheltenham Festival.
In April 2010, Johnson told how he and his wife Sue were robbed of £100,000 at gunpoint during a raid at their farm.
BHA spokesman Paul Struthers said the ban showed it was determined to take decisive action on welfare and integrity issues.
"The panel stated in its reasons that his behaviour 'fell seriously short of the standard to be expected of a licensed trainer' and that 'any lesser penalty would undermine the confidence stakeholders in racing are entitled to hold that, reckless disregard of equine welfare, will not be tolerated,'" he said.
"This decision, and the action of the authority in investigating this case and bringing charges, demonstrates once more that British racing will take decisive and firm action when confronted with issues relating to welfare or integrity."