Effects of α-lipoic acid on growth and antioxidant enzyme activities in common carp (Cyprinus carpio)

This study evaluated the effects of α-lipoic acid (LA) supplementation on antioxidants responses in intestine and liver of Cyprinus carpio juveniles. Four experimental groups were fed in duration of 60 days with a diet containing different levels (0 as control, 0.5, 1 and 1.5g kg−1) of LA evaluating glutathione (GSH) activity, superoxide dismutase (SOD) and total antioxidant activity (TAC) in two organs. Parameters, including survival, weight gain and specific growth rates were also evaluated. The results showed that adding LA supplementation to carp diet led to increased activity of antioxidant enzymes in 1.5 g dose and the difference was significant in 0.5 and 1g groups (p<0.05). There was no significant difference in survival among experimental and control groups (p>0.05). Weight gain in 1 g group was significantly higher than other groups (p<0.05). Specific growth rates exhibited the same response pattern as that of weight gain (p<0.05). The obtained results regarding growth and antioxidant status indicated that LA could be supplemented in diets for Cyprinus carpio at doses between 1 and 1.5g LA kg−1 dry food.