Application of testosterone to epitestosterone ratio to horse urine – a complementary approach to detect the administrations of testosterone and its pro‐drugs in Thoroughbred geldings

• DOI: 10.1002/dta.2109
• Publication Date: 2016-10-13T05:55:59Z
• Authors: Marjaana Viljanto; James Scarth; Pamela Hincks; Lynn Hillyer; Adam Cawley; Craig Suann; Glenys Noble; Christopher J. Wa...; Andrew T. Kicman; Mark C. Parkin
• Keywords: Epitestosterone; Testosterone propionate

Detection of testosterone and/or its pro-drugs in the gelding is currently regulated by application an international threshold for urinary 20 ng/mL. The use steroid ratios may provide a useful supplementary approach to aid differentiating between administration these steroids and unusual physiological conditions that result atypically high concentrations. In current study, ultra-high performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) method was developed quantify (T) epitestosterone (E). used analyze 200 post-race urine samples from geldings order generate reference population. Following statistical analysis data, upper limit 5 T:E ratio proposed. Samples collected 15 with atypical concentrations (>15 ng/mL) but otherwise normal profile, had within those observed applicability detect demonstrated selection incurred propionate, dehydroepiandrosterone (DHEA), mixture DHEA pregnenolone (Equi-Bolic®) administrations. These produced above ng/mL, also proposed 5. conclusion, consideration appears be valuable complementary evaluate whether concentration could caused natural biological outlier as opposed steroids. Copyright © 2016 John Wiley & Sons, Ltd.