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Drug testing and analysis2023; doi: 10.1002/dta.3624

Presence and detection of endogenous steroids in the horse-A review.

Abstract: Detection of doping with steroids that are also endogenous in the horse can be challenging, and a variety of approaches to distinguish exogenous administration from their natural presence are employed. Knowledge of endogenous concentrations of various steroids in different genders of horses (intact male, castrated male and female) and factors that could naturally affect them is beneficial for establishing ways for detection of their use. The current internationally adopted approaches include concentration-based thresholds in urine and plasma, steroid ratios in urine and targeting the administered intact steroid esters in plasma and hair. However, these have their limitations, and therefore, other strategies, such as additional biomarkers and steroid profiling based on longitudinal testing and multivariate analysis, have been investigated and could potentially improve detection of the use of endogenous steroids in horses. This paper aims to provide a comprehensive overview of the steroids (androgens, oestrogens and progestogens) that have been reported to be endogenous to horses in literature, their concentration ranges in different genders and factors potentially affecting them as well as current and possible future approaches to detect their use.
© 2023 John Wiley & Sons, Ltd.
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Publication Date: 2023-12-13 PubMed ID: 38092431DOI: 10.1002/dta.3624Google Scholar: Lookup
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Summary

This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.

This research article presents a detailed review of the challenges in detecting doping with endogenous steroids (those naturally occurring) in horses, and the various strategies used and proposed for their detection.

Detection of Endogenous Steroids

The detection of doping with steroids that are also naturally occurring in horses can be challenging because any trace of the steroid in a horse’s system could be a result of either doping or natural biological processes. As such, researchers employ various methods to determine whether the presence of these steroids is due to exogenous administration (doping) or their natural presence.

  • The primary methods currently used internationally include setting thresholds for steroid concentrations in urine and plasma (the liquid part of blood), comparing ratios of different steroids in urine, and targeting the administered intact steroid esters (a type of compound that results from the reaction between an acid and an alcohol) in plasma and hair.
  • The understanding of the natural (endogenous) levels of various steroids in different genders of horses and factors that could naturally affect them is critical in establishing the methods used to detect their unnatural use.

Limitations in Current Detection Methods and Proposed Strategies

There are limitations in the methods currently in use for the detection of steroid use in horses.

  • Potential variations in the natural steroid concentrations in horses due to factors such as age, diet, and health condition can complicate the threshold and ratio methods.
  • Though the targeting of intact steroid esters in plasma and hair can provide evidence of exogenous steroid administration, this method also has its challenges, as the administered steroids could have degraded, making them difficult to detect.

To address these limitations, other strategies have been explored:

  • Additional biomarkers (substances used as indicators of a particular biological state) have been investigated as potential tools for detection.
  • The profiling of steroids based on longitudinal testing (monitoring changes over a long period of time) and multivariate analysis (a statistical technique used to analyze data with more than one variable) has also been examined as a possible improvement to the current detection methods.

Overview of Endogenous Steroids in Horses

The paper provides a comprehensive review of the different types of steroids – androgens, oestrogens, and progestogens – that naturally occur in horses. It looks at their concentration ranges in different genders and factors that could potentially affect these levels. With this information, researchers may be more equipped to distinguish between natural and unnatural steroid presence, thus improving the detection and prevention of steroid use in horses.

Cite This Article

APA
Viljanto M, Gray B, Scarth J. (2023). Presence and detection of endogenous steroids in the horse-A review. Drug Test Anal. https://doi.org/10.1002/dta.3624

Publication

Drug testing and analysis
ISSN: 1942-7611
NlmUniqueID: 101483449
Country: England
Language: English

Researcher Affiliations

Viljanto, Marjaana
  • LGC, Cambridgeshire, UK.
Gray, Bobby
  • LGC, Cambridgeshire, UK.
Scarth, James
  • LGC, Cambridgeshire, UK.

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Citations

This article has been cited 1 times.
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