Comparative effects of rose hip and corn oils on biliary and plasma lipids in rats

The comparative effects of dietary level and time of feeding corn (CO) and rose hip (RHO) oils on bile and plasma lipid composition were studied. 48 males Sprague Dawley rats were divided in two groups fed semipurified diets containing CO or RHO as the only lipid source. Groups of 6 rats were fed ad libitum diets containing 5% or 15% vegetable oil during 15 or 60 days. Food intake was not dependent on the type of oil, and was higher in 15% oil diets (p < 0.01), increasing with time of feeding (p < 0.001). Bile flow was similar in all groups. Biliary concentrations of cholesterol, phospholipids and bile acids were affected by the time of feeding (p < 0.001). Plasma total and high density lipoprotein (HDL) cholesterol levels were higher in 15% oil fed rats (p < 0.05). Triglycerides concentrations were similar in all groups. The results indicate that oil concentration and time of feeding were the most important variables affecting the lipid composition of rats, independently of the fatty acid composition of the ingested fats.