LAUSR

This experiment investigated the effects of xylanase on growth performance, nutrient digestibility, serum metabolites, and faecal microbiota in growing pigs fed wheat-soybean meal-based diets. Seventy-two crossbred pigs [Duroc × (Landrace × Large White)] pigs (body weight of 23.30 ± 1.51 kg) were allotted two treatments with six pens per treatment and six pigs per pen. The diets were a wheat-soybean meal-based diet (Control group) and a wheat-soybean meal-based diet supplemented with 500 U/kg xylanases (XYL group). The experiment was divided into two periods (phase 1: d 1-35 and phase 2: d 36-70). Xylanase improved G:F during phase 1 and the entire experiment (P < 0.05) and tended to improve G:F during phase 2 (P = 0.09). Compared with the control group, pigs in the XYL group had greater apparent total tract digestibility (ATTD) of dry matter, organic matter, and gross energy on d 35 and d 70 (P < 0.05) and had greater apparent ileal digestibility (AID) of amino acids (histidine, lysine, methionine, and serine) on d 70 (P < 0.05). The faecal microbiota in the XYL group contained greater abundances of g_Terrisporobacter, g_Lactobacillus, g_Clostridium_sensu_stricto_1, and g_Romboutsia than the Control group on d 70. Xylanase increased the faecal Lactobacillus populations on d 35 (P < 0.05). On d 35 and d 70, xylanase reduced the faecal E. coli populations (P < 0.05). Supplementing xylanase to wheat-soybean meal-based diets collectively improved faecal microbiota, and nutrient digestibility, thereby improving growth performance in growing pigs.