HIWU Suspends Trainer Over Alleged Cobalt Finding

In its first public disclosure involving a failed drug test, the Horseracing Integrity and Welfare Unit posted June 16 that it has issued a provisional (immediate) suspension of Mid-Atlantic-based trainer Mario A. Dominguez after it alleges a failed drug test of one of his runners indicated the banned substance cobalt.

In its posting the HIWU said the test findings indicated the banned substance cobalt (the substance and/or its metabolites or markers) was discovered in a collected sample from one of his runners, Petulant Delight , May 24. Dominguez-trained Petulant Delight won a claiming race that day at Parx Racing, earning $10,800 for owner The Hakim's Stable in the 6 1/2-furlong race for horses entered for a $5,000 tag.

As cobalt salts fall into the Erythropoiesis category, they are listed as S2 on the HIWU list of banned substances. Substances in this category can be used to increase red blood cells—blood doping. The HIWU list notes that there is a threshold for cobalt of 0.1mcg/mL total in urine or 0.025 mcg/mL total (free and protein bound) in serum or plasma.

When HIWU has a finding of a banned substance, it puts a provisional suspension in place. (Findings of a controlled medication do not carry an immediate suspension.) A trainer that has a horse test positive for a banned substance can be suspended for up to two years and fined up to $25,000 and be subject to some or all adjudication and legal costs. 

Dominguez will not be able to start horses until the case is resolved. Dominguez has a pair of horses entered June 19 at Parx: We Be There  in the first race and Cartouche  in the ninth. A HIWU spokesperson said that, by rule, those two horses will have to be scratched.

BloodHorse did not have contact information readily available to reach Dominguez to allow him a chance to respond to the allegation.

It's expected that Petulant Delight will soon be disqualified from the May 24 win as HIWU rules say that, "Anti-doping rule violations that arise from a post-race sample automatically lead to the disqualification of race-day results. Any other results that the covered horse obtained from the date the anti-doping rule violation first occurred will also be disqualified."

HIWU's public disclosure at this point does not specifically say if the cobalt findings for Petulant Delight were discovered in a post-race test, although it does list the "date of violation" as May 24—the same date as the race. Petulant Delight, an 8-year-old gelding, has not raced since the May 24 win.

The May 24 win marked the first start by Petulant Delight this season for Dominguez. Before that May 24 effort, the trainer had previously sent him out for 20 starts throughout his career—most recently in September 2022. 

With 12 wins and $239,068 in earnings at the current Parx Racing meet, Dominguez ranks in the top 20 by wins and top 40 by earnings at the meet through June 15. Dominguez has been training horses since 2018 with his top season being 2021 when his stable secured more than $700,000 in purse earnings.