Abstract
1. The effect of methionine supplementation upon pancreatic trypsin, chymotrypsin, pancreatopeptidase E and amylase of chicks given raw and heated soya-bean diets (RSD and HSD) was studied before and after fasting.2. Statistical analysis of the ratios of amylase to pancreatopeptidase E, trypsin and chymotrypsin in each individual chick revealed that methionine supplementation consistently increased the ratio of amylolytic to proteolytic enzymes. This phenomenon was most marked in the fasted RSD group, less in the fed RSD and fasted HSD groups and least in the fed HSD group.3. The results are discussed in relation to methionine metabolism in chicks given RSD and HSD supplemented with trypsin inhibitors.