Excretion profile of boldenone in urine of veal calves fed two different milk replacers

Endogenous boldenone-formation in cattle: Alternative invertebrate organisms to elucidate the enzymatic pathway and the potential role of edible fungi on cattle's feed

“…Moreover, this mechanism could possibly explain the observed increase in Bol-detection in dried out faeces (Table 8), being more exposed to flies and consequently maggots than fresh faeces. Even though the role of phytosterols in the formation of Bol and other steroids has often been suggested, it has only been described in a few studies [50,52,60,61]. In this study, the ability of edible fungi -potentially growing on animal feed -to convert phytosterols into steroids was hypothesised.…”

“…Abbreviations: aBol, ␣-boldenone; bBol, ␤-boldenone. [8] nd->80.0 nd-≤7.0 1.0-10.0 a 0.1-2.0 a Rossi et al [48] ≤7.9 ≤0.2 b na na Nielen et al [9] nd nd 0.1-2.0 a 0.1-2.0 a Sangiorgi et al [10] nd nd --Arioli et al [49] na na nd-10.0 nd Arioli et al [49] 168.7-124664.0 a 331.5 a Draisci et al [50] nd-0.9 nd na na Pompa et al [51] nd nd nd-5.9 27.6-89.0 Pompa et al [51] nd-3090.0 a nd-482.0 a Nielen et al [25] nd-2.7 nd 100.0 a 4.0 a Gallina et al [52] <1.0 nd na na nd: not detected; na: no data available. a Analyte was only detected in dried faeces, not in fresh rectal faeces.…”

In Vitro Androgen Bioassays as a Detection Method for Designer Androgens

“…Naturally occurring steroids such as testosterone or synthetic androgens such as 19-nortestosterone, trenbolone acetate, and medroxyprogesterone are used to illicitly augment growth of animal livestock [42,43]. In addition, prohormones such as dehydroepiandrosterone (DHEA) are being used, and these are often hard to detect if they have been exogenously administered [44]. GC-MS-based screening of material such as meat extracts, feed or urine may fail to detect these substances because deconjugating steps are required prior to GC-MS analysis and these processing steps can destroy the structures.…”

Novel analytical methods for the determination of steroid hormones in edible matrices

“…Microbial transformation of plant sterols into androsta-1,4-diene-3,17-dione (ADD), the precursor of boldenone and androst-4-ene-3,17-dione (AED), precursor of testosterone is frequently described [16][17][18][19][20][21][22]. Metabolisation of plant sterols has been demonstrated in higher organisms [23][24][25]. The physiological effects of phytosterols and mainly their cholesterol lowering properties have increased interest in their occurrence in food products and diets.…”