Relationship of Arginine and Methionine in the Nutrition of the Chick and the Significance of Creatine Biosynthesis in Their Interaction

Adding graded levels of arginine to a corn-soya diet limiting in methionine caused a growth depression in chicks corresponding to the levels of supplemental arginine, which could be alleviated by adding small quantities of methionine. The growth depression created by arginine supplementation was accentuated in the presence of additional glycine or α-aminoisobutyric acid (AIB). Betaine was similar to methionine in alleviating the adverse effect of added arginine. In one experiment supplemental arginine increased creatine in muscle and excreta, indicating that at least one of the mechanisms involved in the arginine-methionine interaction is the formation of creatine. Added levels of lysine or vitamin B6 had no effect on this interaction.