Variations in Plasma Metabolome Shed Light on the Associations Between Lipid Metabolism and Oxidative Stress in Goats Supplemented With Condensed Tannin

This study was designed to characterize the effects of dietary inclusion of condensed tannin (CT) at 2% (wt/wt) dry matter on the goat plasma metabolome and oxidative stress. Barley (BA) and corn (CN) were separately used as starch sources for the control rations, and rations supplemented with CT were BACT and CNCT, respectively. The rations were tested using eight Japanese Shiba × Saanen goats in a replicated 4 × 4 Latin square arrangement (28 days for each period). Plasma was obtained on the last day of each period, and ultra-high-performance liquid chromatography-tandem mass spectrometer analysis was performed. Metabolites of BACT/BA and CNCT/CN were mostly associated with primary bile acid biosynthesis and amino acid metabolism and showed strong relationships with lipid metabolism. Moreover, 2% CT supplementation significantly decreased oxidative stress, and the effect was more evident in BACT/BA than in CNCT/CN. Furthermore, correlation analysis between differential metabolites and oxidative stress revealed that plasma reactive molecules were negatively correlated with metabolites belonging to primary bile acid biosynthesis. The present study provides a better understanding of the relationship between plasma metabolome and oxidative stress and supports a shift in concern about using CT as a strategy to enhance ruminant health and production performance.