Apparent digestibility of non-starch polysaccharides and short chain fatty acids production in the large intestine of pigs fed dried or toasted peas

Peas, dried or toasted, were fed to growing pigs. Peas harvested in 1990 were used in Expt. 1 and peas harvested in 1993 in Expt. 2. In pea cotyledons, 49-55% of the non-starch polysaccharides (NSP) monomers were insoluble. Arabinose and uronic acids and cellulose were the main constituents. In the hulls, 83-84% of the NSP residues were insoluble, with cellulose, xylose and uronic acids as the dominating sugars. The caecum and proximal colon were the sites of highest fermentation. In the caecum, NSP digestibility was 40-48% in Expt. 1 and 29-45% in Expt 2. NSP digestibility values of 84-87% (Expt. 1) and 85-90% (Expt, 2) were observed in the distal colon. Arabinose and uronic acids and galactose were fermented ro a high extent in the proximal large intestine. Xylose and glucose disappeared at a lower extent and to a lower rate, and were fermented more distally in the colon, In spite of the different rate of fermentation of the sugars, no marked changes in the pattern of SCFA were detected along the large intestine. Toasting did not significantly affect the parameters measured.