Comparative apparent digestibility of casein in holoxenic, axenic, and Clostridium bifermentans monoassociated rats

The aim of the present study was to determine the role of the intestinal microflora in the dietary utilization of casein. The apparent digestibility of dry matter, organic matter, energy, and nitrogen was measured in holoxenic, axenic, and Clostridium befermentans monoassociated rats deprived or not deprived of their pancreatic and bile secretions. The apparent digestibility of energy decreased in all the animals whatever the bacterial environment, after ligation of the common duct. Concerning the apparent digestibility of nitrogen, the intestinal microflora allowed the rats to compensate for the absence of the pancreatic proteolytic enzymes. It is suggested that a small part of casein, which was not hydrolyzed when the animals were deprived of their pancreatic and bile secretions, underwent a hydrolysis from the bacterial proteases.