ABSTRACT
Seventy five weanling male albino rats were divided into 5 separate groups each of 15 rats; G I was supplemented with basal diet only [control -ve]. Rats of other groups G II, III, IV and V were intoxicated by malathion in a dose of 137.5 mg/kg body weight [1/10 of non lethal effected dose] for 30 days, while casein and ascorbic acid were given either alone or in combination for 45 [G III, GIV and GV] days. Five rats from each group were sacrificed at 15, 30 and 45 days post-treatment. Serum samples and tissue specimens were subjected for biochemical analysis and histopathological studies respectively. Serum biochemical analysis revealed that malathion suppressed SChE and elevated ALT, AST und ALP activities, caused hyperglycemia and affected lipid profile by increasing triacylglycerol, cholesterol and total lipids concentrations while supplementation with casein and ascorbic acid partially reduced the former metabolic changes. Histopathological examination revealed hemorrhages, severe necrobiotic changes in the internal organs of rats treated with malathion insecticide only, moderate changes were detected in rats treated with casein or ascorbic acid and mild lesions were noticed in rats treated with a combination of casein and ascorbic acid. It was concluded that chronic toxicity incited by malathion insecticides in a rat as a laboratory model was particularly reduced on using ascorbic acid as a natural antioxidant and/or casein as a dietary protein in farm animal ration