Non-targeted metabolomics reveals liver metabolome changes in broiler chickens fed diets supplemented with fermented brewer's grain.

This study was designed to systematically assess the impact of wet-fermented brewer's grains (WFBG) on hepatic metabolic profiles and key regulatory pathways in broiler chickens. In this 21-day experiment, 240 one-day-old male broiler chickens (36.46 ± 0.93 g) were randomly assigned to two groups. The experimental diets contained 0% and 20% WFBG, respectively. Non-targeted metabolomics profiling identified 202 liver differentially expressed metabolites (DEMs), comprising 174 up-regulated and 28 down-regulated species, which were significantly associated with WFBG intervention. Pathway enrichment analysis revealed that these DEMs were predominantly involved in 40 metabolic pathways, including glycine/serine/threonine metabolism, fatty acid biosynthesis, and ABC transporter pathways. Notably, a significant upregulation of these DEMs was observed in the 20% WFBG group (P < 0.05). This finding reveals that WFBG modulates hepatic metabolism via multiple pathways, supporting its application in broiler nutrition.