The Storage of an Unidentified Growth Factor or Factors in the Egg and Its Relation to Chick Growth and Mortality

Abstract

THERE are many reports showing that the composition of the diet fed to hens influences the growth and livability of chicks when the chicks are fed diets deficient in the essential factor being studied. Norris, Wilgus, Ringrose, and Heuser (1936), Lepkovsky, Taylor, Jukes and Almquist (1938), Hunt, Winter, and Bethke (1936), and Clandinin (1946) showed that the riboflavin content of the breeder diet had a marked influence on growth of chicks and the development of deficiency symptoms when the chicks were fed a riboflavin deficient diet. Sherwood and Fraps (1935) and Bearse and Miller (1937) found that a low vitamin A content of the hens’ diet was reflected in poor livability of the chicks when they were fed a vitamin A deficient chick diet. More recently Bird, Rubin, Whitson, and Haynes (1946) reported that the hens’ diet had a marked influence on chick mortality and that supplementing the chick diet .