4-CHLOROTESTOSTERONE ACETATE METABOLITES IN CATTLE AFTER INTRAMUSCULAR AND ORAL ADMINISTRATIONS

The use of 4-chlorotestosterone acetate by farmers for cattle fattenin g was recently demonstrated although the use of this anabolic steroid is strictly forbidden in the European Union. We investigated the metab olism of 4-chlorotestosterone acetate in the bovine species after intr amuscular and oral administration. Nineteen metabolites were detected in urine after intramuscular injection, and eight metabolites were ide ntified. For this purpose, preparative HPLC, mass spectrometry with di fferent ionization modes (electronic impact and chemical ionization), and different acquisition techniques were used (high resolution, selec ted ion monitoring, and scan measurement). Metabolite stereoisomerism was determined on the basis of retention time and organic synthesis. 4 -Chloroepitestosterone (M2), 4-chloroandrost-4-en-3 alpha-ol-17-one (M 3), and 4-chloroandrost-4-ene-3,17-dione (M4) were identified as the m ain urinary markers of intramuscular administration. On the Other hand , 4-chloroandrost-4-ene-3 alpha,17 beta-diol (M7), 4-chloroandrostan-3 beta-ol-17-one (M5), and M2 were the primary indicators of an oral ad ministration. In addition, we have shown that 95% of the metabolites w ere sulfo-conjugated, except for M3, which was partially conjugated to glucuronic acid. Finally, the main metabolites (M2, M3, and M4) were easily identified for 1.5 months after intramuscular administration.