Effect of barley fibres and barley intake on the ileal endogenous nitrogenlosses in piglets

Ilcal endogenous N losses (ENL) were measured, using the N-15 isotope dilut ion technique, in piglets (17 kg) fed different bailey genotypes (naked, sp ring, winter with low/high beta-glucan content) or diets containing 330, 53 0, 730 or 930 g of a blend of barleys/kg diet. The apparent protein and ami no acid digestibilities of the naked variety and the winter variety with a high beta-glucan content were, on average, significantly higher than those for the other two varieties. The ENL were inversely correlated (p<0.01) wit h the apparent digestibilities but the difference between each of them Tt a s not significant (p>0.05). The ENL increased linearly with the inclusion l et el of barley in a N-free basal diet (2 mg endogenous N/g barley). Isolat ed hulls added to a N-free diet at the rate of 100 or 200 g/kg diet exerted no significant effect on the ENL (1.80 g endogenous N/kg diet in both case s vs. 1.76 g for the basal level). On the contrary, the effect of isolated bran, measured under similar conditions, was significantly higher and depen dent on fibre intake (2.59 and 3.31g N/kg diet, respectively). It is conclu ded that the ENL are affected Ly the insoluble bran fibre but not by the hu lls, nor by the level of beta-glucan. (C) 2000 Academic Press.