The Urinary Ratio of Testosterone to Epitetosterone: A Good Marker of Illegal Treatment also in Cattle?

Angeletti, Roberto; Contiero, Lidia; Gallina, Guglielmo; Montesissa, Clara

doi:10.1007/s11259-006-0025-9

Cited by 19 publications

(15 citation statements)

References 4 publications

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“…A study by Angeletti et al . ( 1 ) demonstrated that the ratio between 17β-testosterone and 17α-testosterone in urine cannot be used in bovine animals as an indicator for abuse as it is in human and horse. In 1992 Heitzman ( 13 ) proposed maximum levels of testosterone in bovine plasma depending on sex and age, and these values remained officially recommended until now.…”

Section: Introductionmentioning

confidence: 99%

Development of LC-MS/MS confirmatory method for the determination of testosterone in bovine serum

Woźniak

Matraszek-Żuchowska

Witek

et al. 2017

Journal of Veterinary Research

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IntroductionIn the European Union the use of steroid growth promoters is prohibited under Council Directive 96/22/EC. For effective control of illegal use of natural steroids, highly sensitive analytical methods are required, because sex hormones can be present in very low concentrations in biological samples. The aim of the study was to develop a confirmatory method for the detection of testosterone in bovine serum at ppt level.Material and Methods17β-testosterone and internal standards of 17%-testosterone-d2 were extracted from serum samples with a mixture of tert-butyl methyl ether/petroleum ether and were directly analysed by an LC/MS/MS on QTRAP 5500 instrument with a TurboIon-Spray source operating in a positive ionisation mode. Chromatographic separation was achieved on the analytical column Inertsil® ODS-3 with an isocratic elution using mobile phase consisting of acetonitrile, methanol, and water. Method validation has been carried out in accordance with the Commission Decision 2002/657/EC.ResultsThe method was characterised by good recovery (82%) and precision (R.S.D 17 %). Decision limit (CCα) and detection capability (CCβ) was 0.05 μg L−1 and 0.09 μg L−1 respectively. The method met the criteria set out in Commission Decision 2002/657/EC for the purpose of confirmation in terms of retention time and ion ratio in the whole range of its application.ConclusionsThe developed method is specific and sensitive, suitable for measuring the natural level of testosterone in blood of cattle and for use in routine control programme for the detection of this hormone in bovine serum.

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Section: Introductionmentioning

confidence: 99%

Development of LC-MS/MS confirmatory method for the determination of testosterone in bovine serum

Woźniak

Matraszek-Żuchowska

Witek

et al. 2017

Journal of Veterinary Research

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“…The ratio between 17β-testosterone and 17α-testosterone concentrations in urine used as an indicator for abuse in human and horse doping cannot be used in cattle, as shown by Angeletti and co-workers (1). Therefore the matrix of choice for testosterone abuse examination is serum or plasma.…”

Section: Introductionmentioning

confidence: 99%

Levels of the natural hormones 17β-oestradiol and testosterone in serum of cattle: results from population studies in Poland

Woźniak

Witek

Matraszek-Żuchowska

et al. 2016

Journal of Veterinary Research

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Introduction: The present study is a comprehensive overview of the natural occurrence of 17β-oestradiol and testosterone in serum of cattle in Poland. Material and Methods: The serum samples (n = 826) were collected from cattle within five years. The samples were examined for the presence of oestradiol and testosterone using ELISA or gas chromatography with mass spectrometry. Results: In 98 samples (24%) 17β-oestradiol was detected above decision limits of applied methods, including five samples over the recommended concentration of 0.1 μg L -1 . Of the serum samples taken from cows (≤18 months of age), 95 and 99 percentiles of the animals had 17β-oestradiol concentration below 0.027 and 0.086 μg L -1 and of samples from cows over 18 months of age -below 0.059 and 0.125 μg L -1 respectively. Calculated values for bulls (≤18 months of age) were 0.025 and 0.034 μg L -1 and for the animals older than 18 months of age -0.035 and 0.041 μg L -1 . The natural presence of testosterone was detected in 201 serum samples (48.7%). According to the obtained data, 95% and 99% of cows (≤18 months of age) serum samples had testosterone concentration below 0.05 and 0.23 μg L -1 and the animals over 18 months of age -0.30 and 0.49 µg L -1 , respectively. For bulls these values did not depend on the age of the animals and were in the ranges of 5 -6.3 μg L -1 (95%) and 11.4 -12.1 μg L -1 (99%). Conclusion: Our study showed that the threshold values for these hormones in plasma of cattle designated years ago are correct, but they need to be supplemented for animals older than 18 months.

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“…Abuse of prohormones in livestock production is hard to prove: urinary metabolites are unknown or not significantly above highly fluctuating endogenous levels [6]. Chemical methods have the drawback of detecting only targeted compounds of interest.…”

Section: Introductionmentioning

confidence: 99%

Evidence of the indirect hormonal activity of prohormones using liver S9 metabolic bioactivation and an androgen bioassay

Rijk¹,

Bovee²,

Groot³

et al. 2008

Anal Bioanal Chem

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Prohormones such as dehydroepiandrosterone (DHEA) are steroid precursors that do not show hormonal activity by themselves. Abuse of these prohormones in cattle fattening is hard to prove because of strong in vivo metabolism and the difficulty to detect metabolites which are not significantly above endogenous levels. The aim of the present work was to develop an in vitro assay capable of detecting the indirect hormonal activity of prohormones that might be present in feed supplements and injection preparations. Sample extracts were incubated with a bovine liver S9 fraction in order to mimic the in vivo metabolic activation. Subsequently incubated extracts were exposed to a highly androgen-specific yeast bioassay to detect hormonal activity. Metabolic activation of DHEA, 4-androstene-3,17-dione (4-adione) and 5-androstene-3,17-diol (5-adiol) resulted in an increased androgenic activity caused by the formation of the active androgen 17β-testosterone (17β-T), as shown by ultra-performance liquid chromatography and time-of-flight mass spectrometry with accurate mass measurement. The developed in vitro system successfully mimics the hydroxysteroid dehydrogenase (HSD)-and cytochrome P450-mediated in vivo metabolic transitions, thus allowing assessment of both bioactivity and chemical identification without the use of animal experiments. Screening of unknown supplement samples claimed to contain DHEA resulted in successful bioactivation and positive screening results according to the androgen yeast biosensor.

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The Urinary Ratio of Testosterone to Epitetosterone: A Good Marker of Illegal Treatment also in Cattle?

Cited by 19 publications

References 4 publications

Development of LC-MS/MS confirmatory method for the determination of testosterone in bovine serum

Development of LC-MS/MS confirmatory method for the determination of testosterone in bovine serum

Levels of the natural hormones 17β-oestradiol and testosterone in serum of cattle: results from population studies in Poland

Evidence of the indirect hormonal activity of prohormones using liver S9 metabolic bioactivation and an androgen bioassay

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