American Journal of Clinical Nutrition, Vol 9, 236-243, Copyright © 1961 by The American Society for Clinical Nutrition, Inc.

Serum and Liver Cholesterol, Total Lipids and Lipid Phosphorus Levels of Rats under Various Dietary Regimens

¹ From the Food and Nutrition Department, Utah State University, Logan, Utah

Young rats were fed isocaloric diets containing lard on cottonseed oil at three levels, with and without cholesterol. Other groups of rats were fed lecithin at three levels and alfalfa saponin.

Rats fed lard and cholesterol had higher serum cholesterol values than those fed cottonseed oil. The reverse picture occurred in the liver with higher values for cholesterol and lipids when cottonseed oil was fed. Results from a small group of olden rats maintained on diets with 20 per cent fat for months showed that serum cholesterol was highest on the lard diet but variation in liver cholesterol between fats was small.

Level of fat had slight affect on the serum cholesterol or lipid content. On cholesterol-rich diets, the liver showed a sharp increase in concentration of lipids between the 5 and 13.5 per cent fat diets. Further increases were slight when the diet contained 20 per cent fat.

Cholesterol:lipid phosphorus ratio of the serum was elevated with cholesterol feeding: female rats showed higher ratios than male rats; higher ratios were shown by the rats fed lard as compared to those fed cottonseed oil; and lecithin and saponin feeding prevented this elevation of C:P ratio.

Lecithin at the higher levels and saponin prevented the rise in serum and liver lipids that accompanies feeding of lard and cholesterol.