The Physiological Effects of Diets Rich in Egg White*

Experiments by Parsons, Smith, Moise, and Mendel(1930), on the physiological effects of various protein-rich diets showed that cooked, dried, commercial egg whit,e is unsatisfactory for reproduction and lactation when fed to adult female rats as either 80 or 20 per cent of a well supplemented diet. Bond (1922) found that reproduct,ion was not optimum with 30 per cent of egg white in the ration, and Mitchell (1925), using egg white to furnish 18 per cent or more of protein in the diet, came to the same conclusion. Tha.t the fault, at least on the highest percentages, does not lie in an inadequacy of the proteins of egg white was indicated by the success of Osborne andMende1 (1913,1913-14), Bateman (1916), Bond (1922), Mitchell (1925), Cowgill (1927), and Hartwell (1928) in inducing satisfactory growth of young rats with the use of egg white, at relatively low levels, as the sole source of protein in the diet. Chick and Roscoe (1929), in testing the possible value of egg white as the source of protein in the basal diet for the assay of vitamin B (RI), found, however, that egg white fed as 20 per cent of a relatively purified diet did not maintain the growth of rats to maturity, the growth of some of the rats becoming subnormal even in the first few weeks after weaning. They suggested that some third factor, not identical with the antineuritic nor the antidermatitis factor, present in yeast, is absent from egg white. Although Boas (1924) concluded that egg white does not contain protein adequate for complete nutrition, she reported in 1927, after further investigation, that egg white, coagulated before drying and properly supplemented with known dietary essentials supports satisfactory growth and nutrition in young rats, but that dried fresh egg white or commercial dried Chinese egg