The effects of levamisole on oxidative stress induced by copper intoxication in broilers

Abstract

AIM: To determine the effects of Cu and levamisole on concentrations of Cu and Fe in plasma and liver, and the effects of levamisole on lipid peroxidation induced by Cu intoxication in broiler chickens. METHODS: In a 2x4 factorial study, 80 one-day-old Ross PM3 broiler chicks were fed diets for 21 days containing either 8 mg/kg Cu (Low Cu) or 250 mg/kg Cu (High Cu) and were treated with 0 (L0), 4 (L4), 8 (L8) or 16 (L16) mg/kg bodyweight levamisole per day from Day 7 of the study, on three consecutive days in their drinking water. This treatment was repeated three times, at 3-day intervals. On Day 21, blood samples were collected from each bird for analysis of concentrations of Cu, Fe and malondialdehyde, and activities of aspartate aminotransferase (AST), alanine aminotransferase (ALT), superoxide dismutase, catalase and glutathione peroxidase (GSH-Px). The birds were killed and liver samples collected for analysis of Cu and Fe. RESULTS: Mean concentrations of Cu and Fe in plasma, and Cu in liver, were increased overall in the High Cu groups compared with the Low Cu groups (p<0.001). Compared with the L0 treatment group on the High Cu diet, treatments L4, L8 and L16 decreased concentrations of Cu in plasma, and L8 and L16 increased concentration of Cu in liver (p<0.05). Mean activities of AST and ALT were increased in untreated birds (L0) fed the High compared with Low Cu diets (p<0.01). In birds receiving the High Cu diet, treatments L4 and L8 decreased activities of AST, and L4 and L16 decreased activity of ALT, compared with L0 (p<0.05). The High Cu diet induced an oxidative stress characterised by increased mean concentrations of malondialdehyde and decreased activities of superoxide dismutase, catalase and GSH-Px (p<0.001). Concentration of malondialdehyde, and activities of superoxide dismutase and catalase were not changed following levamisole treatment in birds on the High Cu diet, and activity of GSH-Px was decreased by the L4 and L8 treatments compared with the L0 group. CONCLUSIONS AND CLINICAL RELEVANCE: The results of the study suggest that treatment with levamisole might alleviate the harmful effects of Cu on the liver, as demonstrated by decreased activities of AST and ALT induced by a diet containing 250 mg/kg Cu.