The effect of different carbohydrase and protease supplementation on apparent (ileal and overall) digestibility of nutrients of five hulless barley varieties in young pigs

Two experiments were conducted to investigate the effect of beta -glucanase , xylanase, or an enzyme cocktail (beta -glucanase, xylanase and protease) on nutrient and energy digestibilities at ileal and total tract levels on f ive diets for young pigs based on hulless barley. In experiment 1, twelve C otswold male pigs of approximately 15 kg initial body weight, which were su rgically fitted with a post-valve "T" caecum cannula (PVTC), were used to s tudy the effects of various feed enzyme additions on nutrient digestibility of hulless barley-variety Falcon. In experiment 2, twenty pigs with simila r weight and cannulation as experiment 1 were used to investigate the effec t of adding a cocktail of various enzymes on nutrient digestibility of diet s having one of each of five hulless barley varieties, i.e., Phoenix, Falco n, Silky, Condor or Buck, as an energy source (774 g/kg) and canola meal as protein supplement (200 g/kg). The results from experiment 1 showed that t he supplementation of single beta -glucanase or enzyme cocktail significant ly (P < 0.05) improved apparent ileal digestibility of dry matter (DM), gro ss energy (GE), crude protein (CP), amino acids (AA), neutral detergent fib re (NDF) and total non-starch polysaccharide (NSP). Xylanase supplementatio n significantly (P < 0.05) increased apparent ileal digestibility of NDF, c ystine, isoleucine, lysine, methonine and tyrosine. In experiment 2. positi ve (P < 0.05) effects of enzyme cocktail addition were observed for apparen t ileal digestibility of DM, GE, CP and most of the AA with the magnitude g reater for Buck and Condor. Apparent fecal digestibilities of DM, GE and ND F were also improved (P < 0.05) by the enzyme cocktail addition. Reduction in hindgut fermentation was observed probably due to the improved ileal abs orption of nutrients. (C) 2001 Elsevier Science BY. All rights reserved.