PSXII-19 Effects of monoglycerides supplementation in drinking water on serum and colon digesta metabolomic profiles in weaned pigs challenged with F18 enterotoxigenic Escherichia coli.

Abstract Our previous research suggests that monobutyrin or monovalerin supplementation through drinking water may improve disease resistance by regulating systemic immunity of weaned pigs infected with F18 enterotoxigenic Escherichia coli (ETEC). This study aimed to investigate the effects of supplementing monobutyrin or monovalerin in drinking water on serum and colon digesta metabolomic profiles of weaned pigs experimentally infected with F18 ETEC. Twenty-four weaned pigs (average body weight = 7.29 ± 1.05 kg; 21-24 d old) were individually housed and randomly assigned to one of four treatment groups (6 replicates/group): basal diet (control), basal diet with 0.03% monobutyrin or monovalerin added to drinking water, or 50 mg/kg of carbadox (antibiotic) in feed. The experiment lasted 21 days with 7 days before and 14 days after first inoculation (d 0 post-inoculation [PI]); all pigs were orally inoculated with F18 ETEC (1010 CFU/3 mL) for 3 consecutive days. Serum samples were collected on d 5 and 14 PI and distal colon digesta were collected on d 14 PI to analyze untargeted metabolomics by gas chromatography-time of flight-mass spectrometer (GC-TOF-MS). The metabolomics data were analyzed using modules of a web-based platform, MetaboAnalyst 6.0. Statistical significance was declared at a false discovery rate (q) < 0.2 and fold change > 2.0. Pathway and metabolite set enrichment analysis were performed on identified metabolites that had a variable importance in projection score > 1. In serum, phenylalanine metabolism, alanine, aspartate and glutamate metabolism were the most impacted (P < 0.05) pathways in monobutyrin group, while alanine, aspartate and glutamate metabolism were the most affected (P < 0.05) in monovalerin group when compared to control on d 5 and 14 PI. Supplementation of monovalerin up-regulated (q < 0.2) abundance of serum pinitol compared to control on d 14 PI. In colon digesta, significantly impacted pathways (P < 0.05) compared to control were arginine biosynthesis, starch and sucrose metabolism in monobutyrin group on d 14 PI. In contrast, phenylalanine, tyrosine and tryptophan biosynthesis, glycerolipid metabolism, phenylalanine metabolism, starch and sucrose metabolism, and amino sugar and nucleotide sugar metabolism were impacted (P < 0.05) in monovalerin group. Alanine, aspartate and glutamate metabolism, phenylalanine metabolism, beta-alanine metabolism, and arginine biosynthesis were the most affected (P < 0.05) pathways in serum on d 5 and 14 PI when monobutyrin group was compared to monovalerin group. Influence on arginine biosynthesis and phenylalanine metabolism between the monobutyrin and monovalerin groups was also observed (P < 0.05) in colon digesta at d 14 PI. In conclusion, consistent with diarrhea and systemic inflammation data from previous research, serum and colon metabolomics results indicate that water application of monobutyrin or monovalerin had effects on metabolic pathways associated with amino acid and energy metabolism of F18 ETEC-infected weaned pigs.