Growth performance, gastrointestinal microbial activity and nutrient digestibility in early weaned pigs fed diets containing flaxseed and carbohydrase enzyme

The effects of ground flaxseed (FS) and a multi-carbohydrase enzyme (C) supplement on piglet performance, gastrointestinal microbial activity, and nutrient digestibility were investigated in a 28-d trial. Enzyme supplement provided 500 units pectinase, 50 units cellulase, 400 units mannanase, 1,200 units xylanase, 450 units glucanase and 45 units galactanase per kg of diet. Ninety-six pigs were weaned at 17 d of age (BW, 6.1 ± 0.4 kg, mean ± SD) and based on a 2 ? 2 factorial arrangement arraignment of treatments in a completely randomized design with 6 pens per diet (4 pigs per pen). The diets contained wheat, barley, peas, soybean meal and canola meal with 0 or 12% FS and fed without or with C. Flaxseed was included by changing the levels of the other ingredients to balance the diets  for DE and nutrients.  Diets had similar nutrient contents and met the NRC (1998) nutrient specification with exception of DE, CP and AA, which were 95%, 94% and 97% of NRC requirements, respectively. Diets were fed in a 2-phase feeding program (2-wk/phase). Feed intake and BW were measured weekly and 1 pig per pen with BW nearest the pen average was bled weekly to evaluate plasma urea nitrogen (PUN). On d 28 fresh fecal samples were collected from each pen and 1 pig per pen with BW nearest the pen average was killed to evaluate intestinal microbial activity and nutrient digestibility. Dietary effect on piglet performance was only observed in wk 3 when FS diets decreased (P = 0.005) ADG and G:F, tended to decrease ADFI (P = 0.070) and increased PUN (P = 0.027). An interaction between FS and C was observed for ileal digesta viscosity (P = 0.045) such that C increased viscosity in FS diet but had no effect in non-FS diet. Flaxseed and C interacted affecting ileal ammonia content (P = 0.049) such that in absence of FS, inclusion of C in the non-FS diet reduced ammonia compared to diet without C. Flaxseed and C affected other ileal parameters independently. Pigs fed FS diets had decreased (P = 0.003 to 0.033) anaerobic spore count, organic acids, DM, CP and non-starch polysaccharide (NSP) digestibility than pigs fed non-FS diets whereas pigs fed C supplemented diets had greater (P = 0.009 to 0.008) lactobacilli count, lactate, DM and NSP digestibility than pigs fed unsupplemented diets. In conclusion, FS reduced ileal microbial activity, nutrient digestibilities, and piglet performance in wk 3. Multi-carbohydrase supplement increased ileal DM and NSP digestibilities as well as lactobacilli counts and lactate. Author's Abstract.