Supplementary Values Among Foods. I: Adding Egg to an Adequate Diet Compared with Increasing Vegetables.

Abstract

Sherman and Campbell 1 have shown that in a simplified ration composed of whole wheat and whole milk powder marked improvement in growth, reproduction, lactation and general vigor resulted from increasing the milk from 1/6 to 1/3 of the total weight.

We have fed albino rats simplified rations patterned after diets suitable for children, including milk, cereal food (represented by white flour), an assortment of vegetables, a butter substitute (equaling butter in vitamin A content) and meat residue. The composition of these diets is shown in Table I.

On each diet a 5th generation has been secured, but the present report covers only 3 generations; on each diet approximately 40 animals have been carried to the age of 1 year, and on each over 1000 young have been born. As many young as survived have been reared to the age of 28 days. The 3 diets with varying proportions of vegetables but no egg, supported excellent growth, fair reproduction, but very poor lactation. Growth and fertility were slightly better in the 2nd and 3rd generation than in the 1st, but the percentage of young reared decreased with each successive generation, owing to poor lactation.

On the 4th diet, in which egg was used, there was better growth of the young, earlier maturity of the mothers, higher fertility, and better lactation. These findings are summarized in Table II.

These experiments show that a mixed diet already adequate but not containing egg can be improved by the addition of egg more than by an increase in the amount of vegetables, and suggest special supplementing values for the egg, which require further investigation.