Effect of 19-norandrostenololylaurate on testicular growth in colts.

The research investigates the impact of an anabolic steroid on testicular growth in young horses (colts and foals) with the findings illustrating a reduction in testicular growth following the administration of the steroid, and a subsequent regrowth following cessation of treatment.

Experimental Methodology

• Three separate experiments were conducted using varying amounts of 19-norandrostenololylaurate, an anabolic steroid.
• The horses’ age ranges varied from 3-24 months across the experiments.
• The steroid dosage was either administered every 3rd week or every week, depending on the experiment.
• Each experiment had a control group of colts that were not given the steroid treatment.
• The key measure of impact was testicular width (TW).

Findings

• All treatments led to a decrease in testicular width within 6 to 9 weeks.
• There was a temporary upswing in testicular growth during spring which slightly countered the effect of the steroid treatment.
• Post cessation of the steroid treatment, testicular growth resumed.
• In each experiment, the treated animals’ testicular width was smaller than that of the control (untreated) group a certain period after the last steroid administration.
• Despite the decreased testicular width in treated animals, the difference was not statistically significant when compared to untreated animals.

Interpretation

• The study implies that the anabolic steroid 19-norandrostenololylaurate has a shrinking effect on testicular growth.
• The resilience of testicular growth is also demonstrated, as growth resumed once the administration of the steroid ceased.
• Furthermore, the influence of seasons on testicular growth was noted, with growth increasing during spring.
• However, despite the indication of steroid-induced testicular shrinkage, the study clarifies that the variance in testicular width between the treated and untreated animals was not statistically significant.