Effects of dietary xylanase supplementation on growth performance and gut health of weaned pigs fed a high non-starch polysaccharides diet

Non-starch polysaccharides (NSPs) in cereal grains can negatively affect the growth performance of early weaned pigs. Weaned pigs cannot digest NSPs due to a lack of endogenous enzymes. Feeds containing high levels of NSPs can decrease nutrient digestibility by increasing digesta viscosity and modulating the gut environment. Dietary xylanase (XYL) is used to increase nutrient utilization by degrading NSPs containing anti-nutritional factors. Therefore, this study was conducted to evaluate the effects of XYL on the high NSPs diet on growth performance, frequency of diarrhea, blood profiles, systemic immune responses, digesta characteristics, nutrient digestibility, and intestinal health parameters of weaned pigs. XYL improved (<italic>p</italic> < 0.05) the average daily gain (ADG) and gain to feed ratio from day 1 to 7 and day 1 to 14 compared with the control group (CON). Additionally, pigs fed XYL tended to have a higher (<italic>p</italic> = 0.098) ADG from day 8 to 14 than those fed CON. Pigs fed XYL tended to have a lower (<italic>p </italic>= 0.093) number of white blood cells on day 28 than those fed CON. The XYL group tended to increase (<italic>p </italic>= 0.088) digesta pH in the duodenum, but decreased digesta pH in the jejunum (<italic>p</italic> = 0.069) and cecum (<italic>p</italic> < 0.05) on day 28 compared with the CON. Pigs fed XYL had higher (<italic>p</italic> < 0.05) apparent total tract digestibility (ATTD) and apparent ileal digestibility of dry matter on day 28 than those fed CON. Additionally, the XYL group tended to improve ATTD of energy (<italic>p</italic> = 0.083) and crude protein (<italic>p</italic> = 0.082) compared with the CON. Dietary XYL decreased concentrations of tumor necrosis factor-α (<italic>p</italic> < 0.05), immunoglobulin G (<italic>p</italic> = 0.066), malondialdehyde (<italic>p</italic> = 0.070) in jejunal mucosa compared with CON. In conclusion, supplementation of high NSPs diet with XYL enhanced the growth performance of weaned pigs by enhancing nutrient digestibility through the modulation of the intestinal environment.