Effects of Dietary Supplementation with Mushroom or Vitamin D 2 -Enriched Mushroom Powders on Gastrointestinal Health Parameters in the Weaned Pig.

The objective of this study was to compare the molecular, physiological and microbial effects of mushroom powder (MP), vitamin D 2 enriched mushroom powder (MPD 2 ) and zinc oxide (ZnO) in pigs post-weaning. Pigs (four pigs/pen; 12 pens/treatment) were assigned to: (1) basal diet (control), (2) basal diet + ZnO, (3) basal diet + MP (2 g/kg feed) and (4) basal diet + MPD 2 (2 g/kg feed). Zinc oxide supplementation improved the feed intake ( p < 0.001); increased the caecal abundance of Lactobacillus ( p < 0.05); increased the villus height ( p < 0.05) in the duodenum, jejunum and ileum; increased the expression of chemokine interleukin 8 ( CXCL8 ; p < 0.05); and decreased the expression of pro-inflammatory cytokine gene interleukin 6 ( IL6 ; p < 0.05), tumour necrosis factor ( TNF ; p < 0.05), nutrient transporters peptide transporter 1 ( SLC15A1 ; p < 0.05) and fatty acid binding protein 2 ( FABP2 ; ( p < 0.05) in the duodenum. Whereas dietary supplementation with MPD 2 improved the gastrointestinal morphology ( p < 0.05); increased the total volatile fatty acid concentrations ( p < 0.05); increased the expression of anti-inflammatory cytokine gene interleukin 10 ( IL10 ; p < 0.05) and nutrient transporters SLC15A1 ( p < 0.05), FABP2 ( p < 0.05) and vitamin D receptor ( VDR ; p < 0.05); and reduced the expression of pro-inflammatory cytokine gene IL6 ( p < 0.05), it adversely affected average daily feed intake (ADFI; p < 0.001) and average daily gain (ADG; p < 0.05). Mushroom powder supplementation had a positive impact on gastrointestinal morphology ( p < 0.05) and upregulated the expression of nutrient transporters SLC15A1 ( p < 0.05) and FABP2 ( p < 0.05) and tight junction claudin 1 ( CLDN1 ) ( p < 0.05) compared to the controls but had no effect on the expression of inflammatory markers ( p > 0.05). Furthermore, MP reduced ADFI ( p < 0.01); however, this did not negatively impact the ADG ( p > 0.05). In conclusion, MP and MPD 2 have limited use as commercial feed additives in replacing ZnO in pig diets as feed intake was reduced post-weaning.