The Effect of (Echinacea purpurea) Extract on the Growth and Activity of Antioxidant System Enzymes in Rainbow Trout (Oncorhynchus mykiss)

Echinacea purpurea (EP) a member of the Asteraceae family is one of the most popular herbal medicines. This study was done to evaluate the effects of dietary EP on growth and antioxidant defence status in rainbow trout, Oncorhynchus mykiss. A total number of 360 O. mykiss (mean weight 6.25 ± 0.02 g) were divided into four experimental groups including a control and 3 experimental groups that EP was incorporated in their diet at 0.5, 1 and 2 mg/kg. After 8 weeks of experiment growth parameters and antioxidant defence indices including plasma catalase, superoxide dismutase and glutathione peroxidase activity were measured. Our results showed that EP extract affect growth indices as the highest value of weight gain and SGR was seen in fish fed 2 mg/kg EP. Activity of catalase, superoxide dismutase and glutathione peroxidase did not affect by EP. Results indicated that feeding rainbow trout with EP enriched diets at 0.5, 1.0 and 2.0 g. kg-1 levels significantly enhance the growth but had no effect on antioxidant defence.