The hepatic and duodenal activities of some drug metabolizing enzymes in chickens: influence of infection with Escherichia coli endotoxin and coccidiosis.

The activities of the drug metabolizing enzymes aminopyrine-N-demethylase, aniline hydroxylase and UDP-glucuronyl transferase, together with protein concentration, were measured in liver microsomes and duodenal mucosa from healthy chickens and chickens experimentally infected with Escherichia coli endotoxin, or naturally infected with Eimeria necatrix and Eimeria tenella (clinically classified as slight, moderate or severe infections). E. coli (2 mg/kg, 3 days) and severe coccidiosis significantly decreased the activities of the three enzymes in the liver and duodenum. However, infection by the E. coli endotoxin at lower doses (0.5 and 1 mg/kg, 3 days) and moderate or slight coccidial infections had no significant effect on the activities of these enzymes. Neither E. coli nor coccidial infections significantly affected the liver/body weight ratio. However, infection with the E. coli endotoxin (2 mg/kg, 3 days) and the moderate or severe coccidial infections significantly reduced microsomal protein concentration in the liver.