Lysine and Methionine Requirement of Chicks Fed Practical Diets

ALMQUIST and Mecchi (1942) found the l-lysine requirement of chickens on a synthetic diet composed largely of zein and cerelose to be approximately 0.9 percent. Their work was confirmed by Grau, Kratzer and Asmundson in 1946. Grau (1946) fed two-week-old chickens a diet composed largely of cottonseed meal and cerelose, devoid of any source of vitamin B12, for an eight-day period with supplementary amino acids. He determined that there was a critical need for at least 0.46 percent additional l-lysine in such a ration. On this basis, a lysine deficiency would be likely in a practical diet containing cottonseed meal as the only protein supplement. In 1931, Mussehl and Ackerson reported that cottonseed meal was a less satisfactory protein supplement than soybean meal for chick growth. Ringrose and Morgan (1938) reported that cottonseed meal could be fed successfully as three-fourths of the protein supplement in combination with meat scraps. Curtin . . .