Identification of Endogenous 19-Nortestosterone in Pregnant Ewes by Gas Chromatography–Mass Spectrometry

Abstract

Considered as a xenobiotic for many years, 19-nortestosterone has been extensively studied. Analyses developed to control the illegal use of this steroid in meat-producing animals led researchers to demonstrate the endogenous presence of 19-nortestosterone in several species. In this paper, the natural occurrence of 19-nortestosterone in its alpha form (epinandrolone) in the urine of pregnant sheep was demonstrated using gas chromatography-mass spectrometry. This reference method allowed 17 alpha-nandrolone to be detected and identified, and the absence of the beta epimer in the urine of pregnant sheep to be demonstrated. 17 alpha-Nandrolone was accurately determined at different stages of pregnancy. The analyses showed that epinandrolone, which was not detectable in the urine of non-pregnant sheep, was excreted in small amounts (leading to a < 0.5 ppb concentration) during the first 4 months of pregnancy. 17 alpha-Nandrolone concentrations then increased during the last month until parturition. The origin of this molecule was not determined.

Detection of Nandrolone and Boldenone Abuse in the Ovine by GC–MS–MS

“…Using radioimmunoassay, Vandenbroeck et al [9] reported immunoreactive concentrations of nandrolone at around 2,500 pg mL -1 in male and female sheep urine. In a GC-MS study by Clouet et al [20] in 1997, epinandrolone concentrations in the urine of pregnant ewes were determined to be between the limit of detection (LOD) of 200 pg mL -1 and the lower limit of quantification (LLOQ) of 500 pg mL -1 at 120 days prior to parturition. Concentrations then increased throughout pregnancy and reached 3,400 pg mL -1 at 7 days prior to parturition.…”

Report for 2011 on the results from the monitoring of veterinary medicinal product residues and other substances in live animals and animal products

“…The non-compliant samples were found in bovines (n = 39; 0.13 %), pigs (n = 6; 0.06 %), poultry (n = 6; 0.13 %) and aquaculture (n = 2; 0.57 %). For 26 results of anabolic steroids (80 %), Member States indicated that the source was most likely the endogenous production as reported in previous studies (Clouet et al, 1997;Samuels et al, 1998). No evidence of illegal use was found for other 5 non-compliant results for anabolic steroids.…”

Report for 2013 on the results from the monitoring of veterinary medicinal product residues and other substances in live animals and animal products

“…The non-compliant samples were found in bovines (n = 9; 0.04 %), pigs (n = 19; 0.18 %), sheep and goats (n = 4; 0.35 %) and horses (n = 3; 1.73 %). Some Member States indicated that residue findings on steroid hormones may not be attributable to illegal treatment, as the source was most likely the endogenous production as reported in previous studies (Clouet et al, 1997;Samuels et al, 1998).…”