THE INFLUENCE OF ALPHA-GALACTOSIDASE SUPPLEMENTATION ON THE ILEAL DIGESTIBILITY OF LUPIN SEED CARBOHYDRATES AND DIETARY-PROTEIN IN YOUNG-PIGS

Eighteen cannulated piglets were used in two experiments (six in Exper iment 1 and 12 in Experiment 2) to determine the effect of supplementa tion of the diet with microbial alpha-galactosidase on the ileal diges tibility of the raffinose family oligosaccharides and other nutrients of lupin-based diets, Three semi-purified diets with the seed meal of yellow lupin (Lupinus luteus L.) cvs June and Amulet or narrow-leafed lupin (Lupinus angustifolius) cv Saturn were offered to pigs with or w ithout the enzyme supplementation (5 g kg(-1)). About 80% of the alpha -galactosides were digested up to the end of the small intestine of pi gs (Experiment 1) fed on the diet with cv June without the enzyme supp lementation. When alpha-galactosidase was added to the diet, digestibi lity of alpha-galactosides significantly increased to 97%. Results of Experiment 2 showed that the ileal digestibility of sucrose (92.9%), s tachyose (71.9%) and verbascose (83.4%) of narrow-leafed lupin cv Satu rn was higher than the corresponding values for yellow lupin cv Amulet (86.3, 60.1 and 77.8%). The ileal digestibility of raffinose was 52.2 % for cv Saturn and 40.7% for cv Amulet. The ileal digestibility of to tal non-starch polysaccharides (NSP) was 11% for cv Amulet and 14% for cv Saturn. alpha-Galactosidase supplementation significantly improved the digestibility of the raffinose series oligosaccharides and positi vely affected the ileal digestibility of most amino acids (P < 0.05). (C) 1997 Elsevier Science B.V.