ABSTRACT
Since Wilcock and Hopkins specified that a certain number of amino acids were essential in protein nutrition, an enormous amount of research has concentrated on these constituents of natural proteins. After the work of Osborne and Mendel, Lewis was the first to link the biological value of protein to the proportion of its constituent amino acids. One of the properties of the basic amino acids (lysine, arginine, and histidine) is that they react in the same way as cations to a physiological pH. For this reason their metabolism tends to interact with that of the mineral cations. The interactions among basic amino acids and mineral cations are even more complex. In poultry, potassium and sodium seem to interact with the lysine-arginine antagonism. The sparing action of lysine by these cations in the pig is refuted by a large number of experimental results. Possible interactions seem to be of little importance in practical feed formulations.
