Leucine, pyridoxine and resveratrol supplementation alter metabolic parameters in ponies with equine metabolic syndrome.

BACKGROUND

Supplements claiming to improve metabolic profiles in equine metabolic syndrome (EMS) often lack scientific validation.

OBJECTIVES

To evaluate the effect of a supplement containing leucine, resveratrol and pyridoxine on the metabolic profile in ponies with EMS.

STUDY

DESIGN

Unmasked randomised, placebo-controlled field trial.

METHODS

Thirty-eight ponies completed the trial across five farms. Ponies were age and sex matched per farm and randomly assigned to the supplement (n = 20) or placebo group (n = 18) with owners masked to group assignments. Ponies were sampled at days -1/0 (T1), 7/8 (T2), 30/31 (T3) and 60/61 (T4). Measurements included morphometrics, insulin, triglycerides, nonesterified fatty acids, leptin and adiponectin, a two-step insulin tolerance test and oral sugar test (OST). Biochemical and dynamic testing results were compared across groups and times using pairwise comparisons of the estimated marginal means from mixed model, with significance set at a Tukey corrected p-value of <0.05. Chi2 analyses assessed group differences from the trial onset and conclusion, with significance set at a p-value of <0.05.

RESULTS

In the supplement group, maximum insulin post-OST was significantly reduced between T1/T2 and T3/T4, and bodyweight (bwt) decreased significantly between T1 and T4. By T4, more ponies in the supplement group lost ≥2% of their bwt (p = 0.006), with an average reduction of 8.1 kg (95% CI: -11.4, -4.7) while the placebo group gained an average of 2.6 kg (95% CI: -4.2, 9.4). Additionally, more ponies in the supplement group reduced maximum insulin post-OST by ≥40% (p = 0.01 average decrease 36.6 μU/mL; 95% CI: -60.8, -12.3), compared with the placebo group (average decrease of 3.5 μU/mL; 95% CI: -24.8, 17.8).

MAIN LIMITATIONS: Small sample size across multiple farms may have increased variability and masked some effects.

CONCLUSIONS

Supplementation with leucine, pyridoxine and resveratrol may support weight loss and reduce post-prandial insulin concentrations in ponies with EMS.