Dietary inclusion of xylanase improves growth performance, apparent total tract nutrient digestibility, apparent ileal digestibility of nutrients and amino acids and alters gut microbiota in growing pigs

The study investigated the effects of dietary inclusion of xylanase on growth performance, apparent total tract digestibility (ATTD) of dry matter (DM), nitrogen (N), gross energy (GE), apparent ileal digestibility (AID) of nutrients and amino acids, and faecal and ileal microflora counts in twelve cannulated growing pigs fed corn-soybean meal based diet. Pigs with a body weight of 24.32 ± 1.77 kg were surgically equipped with T-cannulas and randomly allotted to one of four dietary treatments (basal diet supplemented with 0, 450, 900, and 1800 of xylanase U/kg) for a 21-days trial period. Dietary inclusion of xylanase significantly improved daily gain and tended to improve gain: feed ratio (P = 0.048; 0.089, respectively). It also improved AID of DM, N, and GE (P = 0.042; 0.084; and 0.093, respectively). The AID of histidine and glutamic acid were significantly improved by xylanase supplementation (P = 0.015 and 0.021) while the AID of lysine, methionine and threonine tended to be improved (P = 0.097; 0.082; and 0.086, respectively). Xylanse supplementation also increased counts of faecal and ileal Lactobacillus (P = 0.036 and 0.048, respectively) and reduced counts of faecal and ileal E. coli (P = 0.007 and 0.071, respectively). In conclusion, dietary inclusion of xylanase improved growth performance, AID of nutrients and amino acids and had beneficial effects on faecal and ileal microflora, increasing Lactobacillus and reducing E. coli counts in pigs.