Influence of Ingestion of Butter Fat on Body Fat of the White Rat

Abstract

In previous communications 1 , 2 the writer presented evidence indicating that the ingestion of derivatives of butyric and caproic acids by the white rat exerted an effect on the body fat of such animals quite different from that usually observed when fats are fed. The general effect consists of an alteration of body fat accompanied by an incorporation in that fat of derivatives of the ingested fat. While it was apparent, from the investigations referred to, that the tissue fat of rats had been altered as a result of the ingestion of derivatives of the above mentioned acids, no evidence of the presence of the ingested fats in the fat of the rats could be obtained. The results secured when tricaproin was fed were quite satisfactory, since the rats appeared to be normal and grew at the usual rate. On the other hand those on a diet containing the butyryl radical in the form of sodium butyrate appeared to be abnormal throughout the whole experimental period.

This communication is a report of experiments in which the butyryl radical was incorporated in the diet in another manner, namely by feeding considerable amounts of butter fat to the rats. The diet fed consisted of the following mixture: vegex 2%, salt mixture 5%, casein 20%, butter fat 30%, and cornstarch 43%. Each 100 gm. of food contained non-saponifiable matter from 7 gm. of cod liver oil. As in previous experiments the animals were kept on the diet for 8 weeks. At the end of that time they were sacrificed by exposure to illuminating gas. The total lipids were then extracted in a manner previously described. 1 Throughout the whole experimental period no evidence of any abnormality was observed.