Keratin as a Source of Protein for the Growing Chick

Abstract

FEATHER meal has been shown to be of value as a protein source when used to replace limited quantities of various protein feedstuffs in a practical ration (Wilder et al., 1955; Lillie et al., 1956; Naber and Morgan, 1956; Sullivan and Stephenson, 1957; Wisman et al., 1958; McKerns and Rittersporn, 1958; Naber et al., 1961; Poppe, 1965). Because of the good replacement value of feather meal for the chick at high dietary protein levels (20–23%) and poor substituting ability at low dietary protein levels (15%) Sibbald et al. (1962) suggested that feather meal was being used as a source of non-specific nitrogen. Routh (1942) found feather meal to be deficient in tryptophan, methionine, lysine and histidine for the rat; however, even with amino acid supplementation only moderate growth was obtained. Feather meal as the primary source of protein for the chick in practical rations was never as good as …