A comparative effect of mild autoxidation of lard and cottonseed oil on the nutritional response of weanling rats
Nadeau, R.G.; Lewis, W.R.
Proceedings West Virginia Acad Science 36: 11-15
Weanling rats were fed rations containing either 20% lard or 20% cottonseed oil. The fats were fresh or autoxidized at 50[degree] C to peroxide values of 150 or 300 mEq/kg. When the ration contained only 12% protein significant decreases were observed in growth rates, nitrogen retention, and fresh weights of livers, spleens and seminal vesicles from rats fed rancid lard rations. However, when cottonseed oil was the source of fat the only significant effect was a slight decrease in N retention. These differences were of relatively small magnitude and were not observed in preliminary studies when the rations contained 18 or 30% protein or when older rats were used. It appears that a low level of autoxidation of ration fat is sufficient to produce detectable adverse effects in young rats fed a low protein diet even when vitamins are administered separately from the rancid ration. Further, these effects are more pronounced when lard rather than cottonseed oil is the source of fat.