Cal Expo Stewards Suspend Trainer with History of Cobalt Use

Stewards suspended Marissa Tyler after tests revealed that Standardbreds in her barn had excessive cobalt levels.

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The stewards at Cal Expo, a harness racing track located in Sacramento, California, issued an interim suspension on Jan. 30 to trainer Marissa Tyler after tests revealed that a number of Standardbreds in her barn had cobalt levels.

The stewards conducted an ex parte hearing Jan. 29 following a California Horse Racing Board (CHRB) investigation that included both out-of-competition testing and post-race testing of all horses trained by Tyler.

The CHRB has filed three complaints against Tyler, and other matters are pending. As a result, and presented with additional evidence, the stewards took steps to protect the public by issuing the interim suspension pending the final disposition of the violations alleged in the petition, as permitted by Business and Professions Code section 494. Additionally, the stewards placed all 21 horses in Tyler’s barn on the Stewards List, making them ineligible to start. The horses that tested high for cobalt also have been placed on the Veterinarians List, making them ineligible to start until such time as they test within allowable cobalt limits cobalt.

While cobalt is an essential element that is present in vitamin B-12, normal vitamin B-12 administrations do not produce high cobalt readings. Low concentrations of cobalt salts also are found in routine feed and vitamin/mineral supplements, but when used properly, those sources do not cause high cobalt readings. There never has been cobalt deficiency documented in the horse that would require cobalt administrations

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