Authors: Dockalova Hana, Zeman Ladislav, Baholet Daria, Batik Andrej, Skalickova Sylvie, Horky Pavel
Journal: Animals : an open access journal from MDPI
Summary
# Editorial Summary Milk thistle seeds contain silymarin—a complex of flavonoids with potential hepatoprotective and antioxidant properties—yet until now, no research had systematically evaluated how horses digest this compound or how dietary inclusion affects nutrient availability and metabolic markers. Researchers administered escalating daily doses of milk thistle expeller (0, 100, 200, 400, and 700 g) to five mares under identical management, using HPLC-UV analysis to track silymarin digestibility whilst measuring digestible energy, macronutrient digestibility, mineral bioavailability, and a comprehensive blood biochemistry panel including liver enzymes, lipid profile, oxidative stress markers, and plasma silymarin concentrations. The digestibility of silymarin flavonolignans increased proportionally with dietary dose up to the highest level tested; however, this dose-response relationship plateaued at 700 g daily, suggesting a ceiling effect beyond which additional silymarin is not absorbed more effectively. These findings have important implications for practitioners considering milk thistle supplementation for equine liver support or metabolic management, as they demonstrate that silymarin bioavailability does not scale indefinitely with increasing inclusion rates, and suggest an optimum supplementation threshold exists. Further investigation into clinical outcomes, longer-term safety profiles, and whether plasma silymarin concentrations correlate with actual hepatic or systemic benefits would help clinicians make evidence-based recommendations regarding dosage and cost-effectiveness.
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Practical Takeaways
- •Milk thistle seed supplementation in horses shows dose-dependent digestibility, suggesting 400-700 g/day may optimize flavonoligan absorption without further benefit at higher levels
- •Silymarin is a bioavailable supplement for horses with potential hepatoprotective properties, though more research is needed on optimal dosing and clinical applications
- •Consider milk thistle supplementation as a potential supportive therapy for horses requiring hepatic or metabolic support, pending further clinical efficacy studies
Key Findings
- •Digestibility of flavonolignans from milk thistle expeller increased with daily doses up to 700 g/day, then plateaued
- •Statistically significant differences (p ≤ 0.05) were found in digestibility between different daily milk thistle doses (0, 100, 200, 400, 700 g)
- •Blood biochemical profiles and antioxidant markers were monitored to assess systemic effects of silymarin supplementation
- •This was the first study documenting silymarin complex digestibility in horses using HPLC-UV analysis