45 Awardee Talk: Investigation of the nutritional and functional roles of a combinational use of xylanase and β-glucanase on intestinal health and growth of nursery pigs

Abstract

Abstract The objective of this study was to evaluate the intestinal health and growth performance of nursery pigs affected by dietary supplementation of increasing levels of xylanase and b-glucanase combinations. Pigs [n = 40; initial body weight (BW) = 6.5 ± 0.4 kg] were assigned to 5 dietary treatments and fed for 35 d in 3 phases (11, 9, and 15 d, respectively). Basal diets mainly included corn, soybean meal, and distiller’s dried grains with solubles with phytase (750 FTU/kg) supplemented with 5 levels of xylanase and b-glucanase combinations (NSPase) at 1) 0, 2) 280 TXU/kg xylanase and 125 TGU/kg b-glucanase, 3) 560 and 250, 4) 840 and 375, or 5) 1,120 and 500, respectively. Growth performance and fecal score were measured for each phase. On d 35, all pigs were euthanized and collected jejunal mucosa, jejunal digesta, jejunal tissues, and ileal digesta to determine the effects of increasing NSPase levels (%) and NSPase intake on jejunal mucosa-associated microbiota, jejunal digesta viscosity, immune responses, intestinal morphology, feed digestibility, and growth performance. Increasing NSPase level quadratically decreased (P < 0.05) Bacteroidetes (min: 0.7% at 636 TXU/kg and 284 TGU/kg), Prevotellaceae (min: 0.6% at 630 TXU/kg and 281 TGU/kg) in the jejunal mucosa. Increasing NSPase intake quadratically increased (P < 0.05) Firmicutes (max: 72.7% at 604 TXU/kg and 270 TGU/kg), Lactobacillaceae (max: 40.3% at 608 TXU/kg and 271 TGU/kg), and Lactobacillus (max: 40.3% at 608 TXU/kg and 271 TGU/kg) in the jejunal mucosa. Increasing NSPase intake also quadratically decreased (P < 0.05) Proteobacteria (min: 3.8% at 562 TXU/kg and 251 TGU/kg), Helicobacteraceae (min: 1.6% at 560 TXU/kg and 250 TGU/kg), and Helicobacter (min: 1.6% at 560 TXU/kg and 250 TGU/kg) in the jejunal mucosa. Increasing NSPase intake tended to quadratically decrease (P = 0.059) viscosity of jejunal digesta reaching the minimum (1.74 mPa·s) at 751 TXU/kg and 335 TGU/kg. Increasing NSPase level tended to linearly decrease (P = 0.073) jejunal IgG and tended to quadratically increase (P = 0.085) jejunal villus height to crypt depth ratio reaching the maximum (2.62) at 560 TXU/kg and 250 TGU/kg. Increasing NSPase intake tended to linearly increase the apparent ileal digestibility of dry matter (P = 0.087) and ether extract (P = 0.065). Increasing NSPase intake linearly increased (P < 0.05) average daily gain (ADG). In conclusion, increasing the combinational use of xylanase and β-glucanase positively modulated jejunal mucosa-associated microbiota, reduced jejunal digesta viscosity, reduced intestinal humoral immune response, enhanced villus morphology, increased ileal digestibility of nutrients, and increased growth of nursery pigs. The beneficial effects were maximized when xylanase and β-glucanase were supplemented at a range of 550 to 800 TXU/kg and 246 to 357 TGU/kg, respectively.