Impact of dietary xylanase in low- and high-fiber diets on the performance and fecal microbiota of lactating sows and their offspring

Dietary xylanase improves nutrient utilization and may promote beneficial gut microbiota through the production of fermentable oligosaccharides. However, its effects in lactating sows, particularly in combination with different dietary fiber levels, remain poorly understood.

Objective: The aim of this study was to evaluate the effect of xylanase supplementation in high- and low-fiber diets on the performance of lactating sows and their offspring.

Methods: At d108 of gestation, 48 sows were assigned to four treatments in a 2 × 2 factorial design: a low-fiber control diet (LF; LF-Con; 12.43% NDF), LF supplemented with 45,000 U/kg xylanase (LF + XYL), a high-fiber control diet (HF; HF-Con; 13.93% NDF), and HF supplemented with xylanase (HF + XYL). Sow body weight and P2 backfat thickness were recorded at d108 of gestation and weaning. Average daily feed intake was recorded throughout lactation, and piglet body weight was measured 24 h post-farrowing and at weaning.

Results: Sows fed HF diets consumed more feed compared to LF sows. Furthermore, xylanase supplementation significantly increased average daily feed intake, reduced lactation weight loss, and attenuated backfat mobilization compared to unsupplemented controls. Regarding the fecal microbiota, HF diets increased the relative abundance of Prevotellaceae and Rikenellaceae. Notably, an increase in the butyrate-producing genus Roseburia (family Lachnospiraceae) was observed, likely driven by cross-feeding mechanisms. Xylanase supplementation reduced the relative abundance of Prevotellaceae, potentially by altering the availability of their preferred carbohydrate substrates.

Conclusion: Supplementing lactating sows with an endo-1,4-β-xylanase in both LF + XYL and HF + XYL diets influenced sow energy balance by elevating feed intake and reducing tissue mobilization while simultaneously altering the fecal microbiome to a more beneficial, butyrate-producing composition, particularly when using fibrous feedstuffs.

Papadopoulos GA, Giannenas I, Lioliopoulou S, Tassis P, Papageorgiou K, di Benedetto M, van Hoeck V. Effects of xylanase supplementation in low- and high-fiber diets on performance and fecal microbiota of lactating sows and their piglets. Research in veterinary science 2026; 207: 106216. https://doi.org/10.1016/j.rvsc.2026.106216