Protective effect of antioxidant-enriched diets on T-2-toxin-induced damage in tilapia (Oreochromis niloticus)

Mycotoxin contamination of plant-based food adversely affects growth and health of tilapia (Oreochromis niloticus) and a search is underway for naturally occurring biological agents that can protect against these mycotoxins. Therefore, diets containing the antioxidants quercetin, rutin and tea polyphenols were investigated for their effects on T-2-toxin-induced growth behavior, antioxidant response, histopathological changes and T-2 residues in tilapia. Five groups of tilapia were exposed to increasing doses of T-2, supplemented with antioxidants (control, T-2, T-2 + quercetin, T-2 + rutin, T-2 + tea polyphenols) for 20 d to evaluate the protective effects of antioxidants on growth, antioxidant enzyme activity, histopathology, and residues in fish liver and muscle. The results indicated that exposure to increasing T-2 doses significantly decreased the survival rate, weight gain and hepatosomatic index, induced liver cell and myofiber damage, and increased T-2 residues in liver and muscle. Dietary supplementation with antioxidants effectively reduced the damage to fish liver and muscle. Tea polyphenols significantly enhanced liver glutathione-S-transferase activity. In conclusion, quercetin, rutin and tea polyphenols significantly reduced liver and muscle damage in tilapia. Supplementation of tilapia diet with rutin was most beneficial with improved growth, increased liver antioxidant capacity, and markedly reduced liver and myofiber damage. Thus, addition of antioxidants to fish diets could potentially be used to resist mycotoxin-related morbidity and mortality in fish.