By: Frank Angst
The Kentucky Horse Racing Commission has approved $147,000 from the Kentucky Equine Drug Research Council fund for a two-year study that aims to develop an affordable test to detect horses that have been given small levels—microdoses—of erythropoietin.
Heather Knych, of the Ken L. Maddy Equine Analytical Chemistry Laboratory at the University of California-Davis, will conduct the study.
In a letter to the KHRC and presentation at its Feb. 19 meeting, Kentucky equine medical director Mary Scollay said there have been anecdotal reports that blood doping through administration of small doses of recombinant human erythropoietin, or its re-engineered form Darbepoetin, is occurring in racing and evading detection.
The abuse of erythropoietin increases red blood cells, creating a performance-enhancing effect known as blood doping as these cells are thought to carry more oxygen to muscles.
Scollay said in racing the current screening method for EPO substances is limited and the concentrations resulting from micro-dosing may be lower than the sensitivity of the screening method. Furthermore, the effects from this method of doping far exceed the window of detection for EPO substances, which are typically in the blood for less than 48 hours following administration.
In human athletes detection of micro-dosing of EPO has focused on identifying changes at the cellular level, in ribonucleic acid transcription signatures that are indicative of altered red blood cell production. The research intends to follow this lead by applying RNA transcription sequencing to equine blood samples to determine if the approach used in humans could be applied to horses.
Scollay noted that with less genetic diversity in Thoroughbreds than humans, the approach has the potential to be even more effective in Thoroughbreds. Scollay said the approach also could provide the foundation for detecting evidence of doping not related to EPO.
For the study, the investigators propose administering rHuEPO to a six-horse test group and saline to a four-horse control group. Blood samples will be collected throughout the seven-week administration period and for three weeks after the final treatment. The blood will be subjected to RNA sequencing with test horse results compared to control horse results. The top 10 differentially expressed transcripts will be validated and the applicability of the method will be tested by analysis of samples from another set of horses administered micro-doses of rHuEPO.
Most of the study’s two-year time frame will be devoted to data analysis.The proposal originally was submitted to the Racing Medication and Testing Consortium, which asked the KEDRC to consider partnering on funding. The KEDRC recommended $147,000 in funding, 75% of the project’s estimated cost. The KHRC approved that funding Feb. 19.
The KHRC also approved having the KEDRC request bids for a study that would aim to develop withdrawal time guidance for levamisole, which has been demonstrated as a useful adjunct treatment of Equine Protozoal Myelitis. A problem with levamisole is one of its metabolites is aminorex, a potent stimulant that calls for the highest level sanctions when detected.