Prececal digestibility of various sources of starch in minipigs with or without experimentally induced exocrine pancreatic insufficiency.

Low prececal digestibility of starch leads to a higher starch flux into the hindgut, causing a forced microbial fermentation, energy losses, and meteorism. For exocrine pancreatic insufficiency (EPI), lack of pancreatic amylase can be compensated mostly by hindgut fermentation of starch. Even in pigs with complete loss of pancreatic secretion, starch digestibility over the entire tract is reaching levels of controls. To optimize diets for human patients with EPI, the proportion of starch that is digested by the ileum is important. Minipigs were fitted with an ileocecal reentrant fistula (n = 8) to determine prececal digestibility of starch. In 5 minipigs the pancreatic duct was ligated (PL) to induce EPI; 3 minipigs served as controls (Con). Various starch sources were tested in a 1-d screening test; therefore, disappearance rate (DR) instead of digestibility was used. Test meals consisted of 169 g DM of a basal diet plus 67.5 g DM of the starch (without thermal treatment; purified; starch content of 89 to 94.5%) and Cr(2)O(3). The test meal contained (% of DM) starch, 67; crude fat, 1.69; CP, 15; crude fiber, 2.0; and Cr(2)O(3), 0.25. In PL, prececal DR of starch was lower than in Con (P < 0.05) for all starch sources. In Con, prececal DR of starch was almost complete (>90%) but was lower (P < 0.05) for potato (Solanum tuberosum) starch (75.4%). In PL, prececal DR of starch was higher (P < 0.05) for wheat (Triticum aestivum) starch (61.2%) than corn (Zea mays) starch (43.0%) and rice (Oryza sativa) starch (29.2%) and intermediate for potato and field pea (Pisum sativum) starch. For patients with EPI, wheat starch seems favorable due to the higher prececal digestibility whereas raw corn and rice starch should be avoided.