Protective effects of melatonin in reduction of oxidative damage and immunosuppression induced by aflatoxin B 1 ‐contaminated diets in young chicks

In the present study, the ability of aflatoxin B 1 (AFB 1 ) to induce endogenous oxidative damages and the possible ameliorating effects of dietary melatonin (MEL) were investigated. Newly hatched broiler chicks ( n = 240) were fed aflatoxin‐contaminated diets (0.5 or 1 mg kg −1 diet) with or without MEL (40 mg kg −1 bw) supplementation in diet for 40 days. AFB 1 resulted in a significant increase in lipid peroxidation (LPO) in the liver and erythrocytes accompanied with suppression of superoxide dismutase (SOD) and catalase (CAT) enzyme activities of erythrocytes. It also caused a significant reduction in levels of serum proteins and marked elevation in activities of serum transaminases. AFB 1 treatment also decreased both humoral and cell‐mediated immune responses in growing chicks. Simultaneous administration of MEL with AFB 1 resulted in an obvious improvement in all the tested parameters. Long‐term rather than short‐term administration of MEL was more effective in rendering protection against AFB 1 ‐induced toxicity. © 2009 Wiley Periodicals, Inc. Environ Toxicol 26: 153–160, 2011.