Body weight gain decreased in chickens treated over 7 days with lindane at 30 mg/kg body wt (ip); no changes were found in chickens injected with lower doses (10 and 20 mg/kg). Compared to control animals, relative liver and small intestine weights were higher in all groups of chickens treated with lindane. Analysis of the chemical composition of intestinal mucosa showed a significant increase in total lipids, phospholipids, protein, and nucleic acid content, but there was no change in the cholesterol content in chickens exposed to lindane at 30 mg/kg. The activities of brush border maltase and alkaline phosphatase were significantly decreased in treated animals; however, sucrase and aminopeptidase N activities were not modified. (C) 1995 Academic Press, Inc.