Pancreatic tissue, obtained from groups of 24 steers each fed pasture plus free-choice minerals or an all-concentrate ration for 126 days, was analyzed for amylase activity. Feeding grain resulted in a highly significant increase in pancreatic amylase activity. Pancreatic tissue from 48 steers fed grain with corn silage had intermediate amylase activity. Data from wethers with pancreatic duct or common bile duct cannulas to permit collection of pancreatic secretions during dietary change support a conclusion that ruminants adapt to increased grain intake by increasing their production of pancreatic amylase. The time required for full adaptation appeared to be longer than for monogastric animals.