Effect of post-weaning glutamine and/or liquid milk replacer supplementation on pig growth and intestinal development

This study aimed to determine the effect of supplemental liquid milk replacer and/or 1% L-glutamine on intestinal function and growth in weaned pigs. Pigs (12 pens/treatment, each with 10 pigs) were assigned to one of 4 treatments from day (D) 0-10 post-weaning (pw): (1) control diet; dry pelleted starter diet only; (2) control diet plus supplemental liquid milk replacer; (3) control diet with dietary inclusion of 1% L-glutamine and (4) control diet with dietary inclusion of 1% L-glutamine plus supplemental liquid milk replacer with dietary inclusion of 1% L-glutamine. Pig weight and feed disappearance were recorded at intervals up to slaughter at ~ 120 kg. At D7 pw, 40 pigs (n = 10/treatment) were euthanised and intestinal tissues collected for histology and gene expression analyses. Liquid milk replacer supplementation increased average daily feed intake and average daily gain from D0-D10 pw and D20-D47 pw and body weight up to slaughter. It also increased villus height in the small intestine, decreased expression of pro-inflammatory cytokines (IL17, IL18, IL22) in the jejunum and increased faecal abundance of Rikenellaceae RC9 and Oscillaspiraceae UCG-002 at D11 pw. In conclusion, while glutamine supplementation did not affect pig growth or intestinal integrity, milk replacer increased feed intake and improved intestinal health and lifetime growth in pigs.