Effect of normal microbial flora on intestinal surface area

Abstract

The mucosal surface area of the small intestine was determined in young adult, germfree and conventional rats. On the average, the germfree values were found to be 30% lower than those of conventional animals. This reduction was pronounced in the mid- and lower parts of the small intestine and relatively slight in the upper segment. It is assumed that the higher surface area values of conventional rats are due to the "physiologic" stimulation by the normal microbial flora.