Effect of dietary protein on porcine colonic microstructure and function

Twelve feeder pigs were used to determine the effects of dietary protein on colonic microstructure and function. Scanning electron microscopy indicated marked differences in mucosal structure of pigs fed 12% vs 20% crude protein. Quantitative assessment of the morphologic features of the colon, using light microscopy, indicated significant differences in the mucosa of pigs fed 12% vs 20% crude protein and significant differences between the proximal and distal portions of the colon. Morphologic changes were associated with differences in the colonic transport of fluids and electrolytes. Dietary protein principally affected the transport of sodium, bicarbonate, and acetate. The transport of total volatile fatty acids and acetate flux were significantly different between the proximal and distal portions of the colon.