Digestibility of fibre sources and molecular weight distribution of fibre fractions in ileal digesta of growing pigs.

Seven post-valve T-caecum cannulated growing pigs were used in a change-over experiment with four diets and four 14-day periods to evaluate the total tract apparent digestibility (TTAD) and the ileal apparent digestibility (IAD) of diets with inclusion of chicory forage (CFO), sugar beet pulp (SBP), wheat bran (WB) and grass meal (GM), as well as the TTAD of the mentioned fibre sources. Moreover, this experiment evaluated the molecular weight distribution of soluble non-starch polysaccharide (NSP) fractions in diet and ileal digesta from pigs fed the CFO and SBP diets. The experimental diets were balanced to have similar NSP content and compromised of one part of the basal diet and one part of the four fibre sources (CFO, SBP, WB and GM). In addition, all pigs were fed the basal diet during a 14-day period before and after the experimental periods. Diet affected the TTAD of all dietary components except glucose. The TTAD of organic matter (OM) was higher for Diet SBP than for Diets WB and CFO, showing both were higher than Diet GM. The TTAD of NSP was higher for Diet SBP than Diets WB and GM. The IAD of OM was higher in Diet SBP than in the other diets. The IAD of NSP was lower in Diet WB than in the other diets. The TTAD of OM and energy of CFO was 0.43 ± 0.04 (standard error), which is similar to that reported for commonly used forage crops. The molecular weight distribution in ileal digesta showed different distributions between Diets CFO and SBP as well as between digesta from pigs fed these diets.