Development of an Experimental Animal Model and Study of the Effect of Dietary Fats on Cholesterol Metabolism

Summary The effect of saturated (beef tallow) and polyunsaturated (corn oil) fat diets on plasma cholesterol, bile flow and composition, and excretion of fecal steroids, was studied in 5 female and 6 male miniature swine. The animals were fitted with a modified Baldwin T-tube in the common bile duct for bile sampling and a catheter in the duodenum for reinfusion. Plasma cholesterol levels were increased by beef tallow and decreased by corn oil. Both fats caused an increase in the secretion of bile, biliary lipids and bile acid pool size. The increases were significant when the source of fat was corn oil. The fecal neutral steroid excretion measured in the male swine was increased by both fats. However, only the polyunsaturated fat diet caused a significant increase in the fecal acidic steroid excretion.