Research findings at the University of Kentucky's Gluck Equine Research Center could make the use of urine in post-race drug testing a thing of the past within a very short time. Urine has been the body fluid of choice in drug testing because the horse's kidney concentrates whatever is in the blood. The disadvantages are that urine testing relates poorly to blood concentration and drugs sometimes be found for a long time in urine.
Blood is a much more satisfactory medium, but the concentrations of drug are much smaller.
This makes detection and quantitation more challenging. An ideal method would be highly sensitive and specific and require only a small volume of sample. This method now has arrived. For racing chemists and regulators, this means better technology because. For horse owners, it means making cutoffs much fairer because it eliminates the inherent variability of testing urine.