Supplementary Values of Animal Protein Concentrates in Chick Rations

Abstract

When used as supplementary sources of protein in chick growing rations, tankages gave decidedly inferior results, meat scraps and cracklings gave much better but yet unsatisfactory results, while vacuum-dried beef and whale meat meal gave very satisfactory results. Analyses of animal protein concentrates were made for the estimation of intact protein, protein decomposition products, undigestible protein and hot-water-soluble protein. These analytical characteristics were found to exhibit a good correlation with nutritive value for chicks, when assigned the relative values of 100, 40, 0 and 40, respectively. Such analytical methods offer a possibility for the rapid laboratory determination of protein quality in commercial concentrates. The cystine, tryptophane and hydrogen sulphide content of the protein concentrates could not be used as a basis for predicting their nutritive values.