FORMS OF NITROGEN IN THE STOOLS OF INFANTS

It has for some time been recognized that the amount of nitrogen lost in the stools of infants is rarely of great importance from the point of view of nutrition. The percentage of the intake which escapes absorption seldom constitutes a serious loss. It seemed possible, however, that significant information concerning the manner in which the alimentary tract handles the food proteins under varying conditions might be obtained by a study of the relative proportions of the fecal nitrogen which are excreted in the form of protein, and of amino acids and ammonia, the two chief final split products of protein. When proteins are digested under aseptic conditions by the intestinal enzymes, trypsin and erepsin, amino acids are the main products, and the amount of ammonia is relatively small. Putrefactive bacteria, on the other hand, are capable of changing a large percentage of the nitrogen of proteins and amino acids