Macronutrient selection in an animal model of cholestatic liver disease

Diet selection was investigated in an animal model of cholestatic liver disease produced by bile duct ligation. Animals self-selected diets from separate sources of macronutrients (protein, fat, carbohydrate). Diet selection was evaluated when the fat source was comprised of either a primarily medium-chain fat (coconut oil) or a primarily long-chain fat (Crisco vegetable shortening). Relative to intakes of control animals, bile duct ligated (BDL) animals consuming the long-chain fat decreased fat intake, decreased protein intake, and increased carbohydrate intake. Consumption of the fat source was decreased in BDL rats fed the medium-chain fat relative to intakes of control animals, however carbohydrate and protein intakes were not affected. Total caloric intake was comparable to control intakes by day 16 post-ligation in BDL rats fed the long-chain fat and by day 11 in BDL rats fed the medium-chain fat. Body weight gain was significantly greater in BDL rats fed the medium-chain fat than in those fed the long-chain fat. Mortality was 44% in BDL animals fed the long-chain fat, and 0% in those fed the medium-chain fat. The results suggest that BDL animals make dietary selections which may decrease the severity of liver disease. Differences between ligated animals consuming either medium- or long-chain fats suggest that some fat sources may be more beneficial during cholestasis.