RÉSUMÉ
The Effect of organophosphorous insecticides compounds [Malathion and Fenitrothion] on certain aspects of carbohydrate metabolism in the freshwater fish Tilapia zillii exposed to 1/3 LC[50] of both insecticides for 96 hours was studied. Organophosphorous compounds were found to affect some parameters of carbohydrate metabolism. Muscle and liver glycogen decreased significantly accompanied with significant increase of the plasma glucose and the specific activity of phosphorylase enzyme in both liver and muscles. The activity of Succinate dehydrogenase [SDH], lactate dehydrogenase [LDH] and malate dehydrogenase [MDH] showed a significant decrease in liver and muscle tissues. Alanine transferase [ALT] and Aspartate transferase [AST] in liver and muscles also showed a significant decrease. Significant alterations in the content of metabolites and enzyme activity under malathion and fenitrothion toxicity seemed to suggest marked shift from aerobic to anaerobic condition