She added: “You did endanger the horses in your care. Luckily, they didn’t break down. You tried to gain an unfair advantage. I hope you accept that, but I don’t think that you do. At the end of the day, unquestionably, you undermined the integrity of horse racing.”

Mr. Servis, who was also ordered to pay $163,932 in restitution and a $30,000 fine, is to report to prison on Nov. 1. He addressed the court briefly during the hearing, which lasted more than two hours. He broke down in tears before reading his statement, and the judge asked if he wanted a break, but his lawyer, Rita Glavin, said he was able to proceed.

“No words can explain how remorseful and sorry I am over the decisions I’ve made and the people I’ve let down and the people I’ve hurt, mostly my wife and two sons,” he said as Ms. Glavin placed her hand his shoulder. “I will live with this for the rest of my life, and I am most truly sorry, and I throw myself at the mercy of the court.”

Mr. Servis pleaded guilty in December 2022 to two charges, one felony and one misdemeanor, related to the use of two banned substances: clenbuterol, a bronchodilator, and SGF-1000, a chemical compound that was said to promote stamina and endurance. He was sentenced to three years in prison for the felony charge and one year for the misdemeanor, to be served consecutively.

Four years was the maximum sentence that Judge Vyskocil could have levied against Mr. Servis, 66, for the guilty pleas on the two counts. Before entering into the plea agreement, Mr. Servis could have faced up to 25 years in prison had he been convicted on charges of conspiracy to commit mail and wire fraud.