Dietary wet fermented Brewer's grains modulate hepatic metabolism in pullets

This study was conducted to evaluate the effects of wet-fermented brewer's grains (WFBG) on liver metabolism in pullets. A total of 120 female 84-d-old pullets (575.2 ± 4.3 g) were randomly allocated into 2 treatments (0% and 20% WFBG) with 6 replicates per group and 10 birds per replicate in this 28-d experiment. Birds fed 20% WFBG had higher (P < 0.05) superoxide dismutase (SOD) level and lower (P < 0.05) malondialdehyde (MDA) content in the liver compared with the control group. In total, 324 liver differentially-expressed metabolites (DEMs) including 208 up-regulated DEMs and 116 down-regulated DEMs were identified and considered to be related with WFBG. Pathway analysis revealed that these DEMs were mainly involved in 64 metabolic pathways including metabolic pathways metabolism, glycerophospholipid (GP) metabolism, linoleic acid (LA) metabolism, arachidonic acid metabolism (ARA), and alpha-linolenic acid metabolism. Furthermore, untargeted metabolomic analyses uncovered 18 common up-regulated DEMs and 8 common down-regulated DEMs in GP, LA and ARA metabolism in the 20% WFBG group (P < 0.05), such as lysophosphatidylcholine (LPC(18:0/0:0), LPC(0:0/20:4)), lysophosphatidylethanolamine (LPE(22:6/0:0)), and 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine. Overall, the inclusion of 20% WFBG in the diets of pullets led to alterations in liver metabolism.