A COMPARISON OF THE UTILIZATION OF RAPESEED OIL AND CORN OIL BY THE RAT

Abstract

The effects of Golden rapeseed oil and corn oil on weekly weight gains, food consumptions, liver storage of vitamin A, plasma and adrenal cholesterol concentrations, organ weights, and testes histology were determined in Wistar rats for 5 weeks after weaning. At each weekly interval, animals fed rapeseed oil showed lesser weight gains and food consumptions, but, when body weight gains were adjusted for food consumptions by covariance analyses, differences largely disappeared. Liver storage of vitamin A was similar with both oils. Testes of animals fed rapeseed oil exhibited no alteration in cellular characteristics, but a reduction in tubular size. When fed to older rats, rapeseed oil again produced smaller weight gains which were accounted for at 4 weeks' time by a depressed appetite.Similar weight gains were obtained with corn oil and rapeseed oil when the oils were paired fed and when adjustments for food consumption were made by covariance analyses of weight gains of animals receiving the oils ad libitum. With corn oil supplied on a restricted basis the testicular tubules were smaller than those obtained with unrestricted feeding of corn oil. The absorption of corn oil and rapeseed oil fed ad libitum was 95 and 92% respectively. It was concluded that the two oils were not very differently utilized.