Detection of the administration of 17β‐nortestosterone in boars by gas chromatography/mass spectrometry

Abstract

17beta-Nortestosterone (17betaN) is illegally used in livestock as a growth promoter and its endogenous production has been described in some animals, such as adult boars. In this paper, the metabolism of 17betaN in boars has been studied by gas chromatography/mass spectrometry (GC/MS) in order to identify markers of the exogenous administration. Administration studies of intramuscular 17betaN laurate to male pigs were performed. Free, sulphate and glucuronide fractions of the urine samples were separated and the steroids present were quantified by GC/MS. 17betaN was detected in some pre-administration samples. After administration, 17betaN, norandrosterone, noretiocholanolone (NorE), norepiandrosterone, 5beta-estrane-3alpha,17beta-diol and 5alpha-estrane-3beta,17beta-diol were detected in different fractions, being the most important metabolites, 17betaN excreted as a sulphate and free NorE. Samples collected in routine controls were also analyzed by GC/MS to identify endogenous compounds. 17betaN, norandrostenedione and estrone were detected in almost all the samples. No other 17betaN metabolites were detected. According to these results, the detection by GC/MS of some of the 17betaN metabolites described above, different from 17betaN, could be indicative of the exogenous administration of 17betaN to boars.

Analysis of 19-nortestosterone residue in animal tissues by ion-trap gas chromatography-tandem mass spectrometry

“…Traditionally, the gas chromatography coupled to mass spectrometry (GC-MS) method is accurate and suitable for detecting steroid hormones and their metabolites simultaneously, and is used as the confirmatory method. In the veterinary field, methods based on GC-MS have been reported to confirm the administration of 19-NT to horse (Houghton et al, 1978;Yamada et al, 2008), to swine (Bagnati and Fanelli, 1991;Petersen et al, 1994;Ventura et al, 2008), and to bovine (Dubois et al, 1998), through identification of 19-NT or its main metabolites. However, no reports were detailed to directly identify 19-NT residue in meat from bovine or ovine.…”

A review of analytical strategies for the detection of ‘endogenous’ steroid abuse in food production

“…For example, 19-noretiocholanolone was at one time considered to be a qualitative marker metabolite for detecting the abuse of nandrolone in the porcine, [41] but was subsequently discovered to be endogenous when more sensitive methods were applied. [42] Therefore, it may be wise to restrict the reporting of marker metabolite results to those that are determined to be at least above the limit of detection (LOD) that was applied in the initial validation study or, depending upon the balance of risk, to apply a safety factor to the LOD below which a compliant result will be reported.…”

“…To put these thresholds into context, in a recent study administering 2 mg/kg nandrolone laurate via intra-muscular injection to six boars aged 8-10 weeks, the mean free fraction 19-noretiocholanolone concentration at the last time-point of the study (15 days following administration) was 28,400 pg/ml, with a range of 9600 to 53 600 pg/ml. [41] The suggested thresholds should therefore be able to detect the abuse of nandrolone for several weeks in the majority of treated animals and hence lead to rates of both low false compliance and non-compliance. The validation of these thresholds is significant as there are currently no other published methods available for the detection of nandrolone abuse in the porcine.…”

Optimised deconjugation of androgenic steroid conjugates in bovine urine

“…And further nortestosterone and a 3β-hydroxy metabolite are excreted as sulphate conjugates (Schänzer 1996;Scarth et al, 2009). Following the administration of nortestosterone laurate to boar, nortestosterone sulphate was the predominant metabolite obtained (Ventura et al, 2008).…”