Nitrogen metabolism in rats and pigs fed inulin

This study was conducted to determine the effect of inulin, added to a non-purified diet, on nitrogen metabolism in rats and ileum-fistulated pigs. Ileal and fecal nitrogen excretion in pigs as well as nitrogen retention in both species were not influenced by inulin consumption. Fecal nitrogen excretion was significantly higher in rats fed inulin. This effect was paralleled by a shifting of nitrogen excretion from the renal to the fecal site. Moreover, cecal ammonia concentrations decreased upon feeding inulin, indicating that ammonia was more utilized in bacterial mass production. No effect of inulin intake on plasma urea concentration was found. The observed lowering of intestinal ammonia is an important aspect of inulin consumption as ammonia may interfere with mucosal cell cycle.