Urinary excretion of 5(10)-estrene-3beta,17alpha-diol and estrone by the female horse: complementary indicators of early pregnancy screened with regard to a putative anabolic doping practice.

The research article examines the use of certain urinary indicators to detect early signs of pregnancy in female horses, a factor that can potentially be manipulated for enhancing physical performance in horse racing. The study evaluates the viability of two conjugates, 5(10)-estrene-3beta,17alpha-diol (EED) and estrone (E1), as detection tools.

Overview of the Research

• The research focuses on understanding how early pregnancy detection could prevent misuse for enhancing physical performance in horse racing.
• It centers around putative anabolic steroid action, which could enhance physical performance, although EED and E1, the conjugates analyzed, lack anabolic properties in horses.
• The relevance is due to certain rules of horse racing – pregnant mares are allowed to compete under specific conditions, therefore the detection of pregnancy status is critical.

Methods Employed in the Study

• Pregnancy screening in horses is generally accomplished using a plasma equine gonadotrophin (eCG) immunoassay, valid for the period between Days 40 and 120.
• However, this research investigated the application of gas chromatography-mass spectrometry to screen for urinary anabolic steroids with additional evaluation of the conjugates EED and E1.
• These conjugates could potentially help extend the detection period behind that of eCG, specifically during Days 70 to 250.

Significance of EED and E1 Conjugates

• Assessing EED and E1 during pregnancy and an estrus cycle indicated a significant difference in the excretion values, which could be attributed to either the placenta or the ovarian follicle.
• Peak values of EED and E1 markers would be enough to serve as a diagnostic tool, as they could be visually inspected using chromatographic tracings.
• The identity of EED has been proven in both urine and placental tissue with the use of GC-MS(n).

Implications of the Research

• This discovery could add another layer to the screening process for early pregnancy detection in horses, therefore preventing potential doping or performance enhancement malpractices.
• This research underscores the importance of stringent surveillance mechanisms in horse racing to ensure fair competition and the wellbeing of the animals.