The Value of Various Feeds as Sources of Arginine, Histidine, Lysine and Threonine for Poultry

IN A previous paper (Schweigert, 1947) the leucine, valine, isoleucine and phenylalanine contents of various feed materials used in rations for poultry were presented. Data were also obtained on the variability in the values for different samples of some of the feeds and on the values for certain poultry rations calculated from data on the individual ingredients and determined by actual analysis. This work has been extended and similar data have been obtained for arginine, histidine, lysine, and threonine. Microbiological methods have been used throughout for the amino acid analyses and a comparison of the analytical data with the reported amino acid requirements of poultry has been made. EXPERIMENTAL Some of the samples used in earlier work were used in the present investigations. In addition several other samples of the same feed materials as well as samples of different feeds were included. Determinations of arginine, histidine and threonine were made . . .