Effect of oral antioxidant supplementation on blood antioxidant status in trained thoroughbred horses.

Authors: de Moffarts B, Kirschvink N, Art T, Pincemail J, Lekeux P

Journal: Veterinary journal (London, England : 1997)

DOI: 10.1016/j.tvjl.2003.12.012 PubMed: 15683765Log in to save

Summary

# Editorial Summary Training stress in thoroughbreds generates oxidative load that can compromise performance and recovery, yet little was known about whether supplementation could meaningfully restore antioxidant balance under real-world conditions. De Moffarts and colleagues monitored 40 trained thoroughbreds over three months, measuring a comprehensive panel of blood antioxidants including water- and lipid-soluble components, enzymatic systems (superoxide dismutase and glutathione peroxidase), and trace elements critical to antioxidant function. Unsupplemented horses showed significant deterioration after three months—glutathione, superoxide dismutase, glutathione peroxidase and selenium all declined substantially, whilst oxidised glutathione increased, indicating progressive oxidative stress. An oral antioxidant mixture prevented the decline in glutathione peroxidase and selenium whilst meaningfully elevating both lipid-soluble (alpha-tocopherol, beta-carotene) and water-soluble antioxidant capacity. For practitioners, these findings suggest that trained horses benefit from targeted supplementation to maintain enzymatic antioxidant defences and micronutrient status during competitive conditioning, though the relationship between improved blood markers and measurable performance gains warrants further investigation in sport horse populations.

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Practical Takeaways

•Trained thoroughbreds experience measurable oxidative stress during regular training, which can be partially mitigated with oral antioxidant supplementation
•Antioxidant supplements appear to preserve glutathione peroxidase activity and selenium status, both critical for exercise-induced oxidative protection
•Individual variation by age and sex suggests supplementation protocols should be tailored rather than applied uniformly to all horses

Key Findings

•Control group showed significant antioxidant imbalance after 3 months with decreased GSH, SOD, GPx, and Se (P < 0.05) and increased GSSG (P < 0.05)
•Oral antioxidant supplementation prevented GPx and Se decline and significantly increased ACW, alpha-tocopherol, beta-carotene, and ACL (P < 0.05)
•Significant sex- and age-related differences were found for AA, ACW, alpha-tocopherol, SOD, GPx, and Se
•Strong correlations identified between ACW-AA, ACL-alpha-tocopherol, GPx-Se, and markers of muscle damage (CPK)

Conditions Studied

oxidative stress in trained thoroughbred horses

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