Dietary silymarin, Silybum marianum extract ameliorates cadmium chloride toxicity in common carp, Cyprinus carpio

The present study evaluated the protective effects of silymarin extract (SIE) on cadmium chloride toxicity in common carp, . Four experimental groups were considered for the experiment including: SIE (control): non-SIE-supplemented fish, SIE : fish supplemented with 400 mg SIE/kg diet, SIE : fish supplemented with 1400 mg SIE/kg diet, SIE : fish supplemented with 2400 mg SIE/kg diet. Fish were fed experimental diet for 60 days and then exposed to cadmium chloride (1.5 mg/l or 25% of LC50-96 h) and antioxidant defense components and the survival rate assayed. After 60 days feeding trial, total antioxidant capacity (TAC) levels significantly increased (P0.01) and acetylcholinesterase (AChE) levels (P>0.01) remained unchanged during the feeding period in all treatments. Hepatic catalase (CAT) in all SIE supplemented groups and superoxide dismutase (SOD) and glutathione peroxidase (GPx) in 1400–2400 mg SIE/kg diet treatments significantly elevated (P0.01) in all experimental groups over feeding period. After exposure to cadmium chloride, TAC levels were significantly elevated (P