Officials said the classification of erythropoeitin — the blood-doping agent commonly known as EPO — as a prohibited practice has curbed its use in some jurisdictions but a definitive test for the substance is a must if any regulation is to have teeth.

Medication was just one of the topics discussed during the initial sessions of the joint meeting of the Thoroughbred Racing Association, Harness Tracks of America, and Racetracks of Canada March 13 in Hollywood Beach, Fla. But the subject spilled over into another arena when regulators were called key to any successful enforcement policy.

“Until there is a definite positive test, there is very little that can be done,” said Lonny Powell, president of the Association of Racing Commissioners International, the organization that adopted the prohibited-practice model for substances that can’t be tested on race day. “Prohibited practices have been adopted by many jurisdictions, and that has been a beacon of light.”

Currently, there is a test for EPO antibodies. It has produced “positives” in Louisiana, New York, and Texas, but because it’s not definitive, participants can only be warned and then monitored. Dr. Ken McKeever, the Rutgers University physiologist who is working with Dr. George Maylin of Cornell University to develop the test, said the evidence is strong even without the test