Presence of β-boldenone sulphate and glucuronide in urine of untreated beef cattle

The use of the anabolic steroids in livestock breeding is prohibited by the EU legislation. As regards β-boldenone, the presence of its conjugates at any levels in urine is a proof of illegal treatment. A debate on the biomarker indicating the illicit use of boldenone is nevertheless in progress. The sulphate and glucuronide metabolites of β-boldenone were determined in urine from untreated, and under veterinary control, Friesian and Limousine beef cattle. A new method for the direct determination in urine of the II phase metabolites of β-boldenone by HPLC-MS/MS was used after extraction trough immunoaffinity columns.The preliminary data show the presence of the sulphate and glucuronide forms in the 75% and 67% percent of urine samples collected at the farm from the studied animals, respectively, and its absence in those from slaughterhouse. These results suggest that presence of β-boldenone conjugate, as both sulphate and glucuronide, in bovine urine cannot be always considered a biomarker of illicit treatment but that a threshold level should be set. These preliminary data need to be strengthened through a wider study including negative and experimentally treated animals.