The Action Potential of Antioxidant Grape Seed Proanthocyanidin as a Rumen Modifier to Mitigate Rumen Methanogenesis In Vitro

Grape seed proanthocyanidin (GSP) contains polyphenolic bioflavonoids ubiquitously found in the lignified portions of grape seeds from winery and distillery industries, as an antioxidant. To explore its potential a rumen modifier methanogenesis inhibition, 2 × 5 factorial experiment was conducted to determine effect GSP at 0, 15, 30, 60 120 mg/g substrate on fermentation two representative total mixed rations (HY, diet for high-yield (>2 kg/d) lactating cows, LY, low-yield (<25 cows). By using MIXED procedure, after 48 h vitro incubation, increasing addition linearly decreased dry matter digestion (IVDMD) slowed down rates ration (RmaxS, g/h) kinetic gas production (RmaxG, mL/h), with decreases being more pronounced LY than HY group (p < 0.05). The hydrogen recovery (2Hrec) altered composition. molar CH4 proportion significantly reduced both mg 0.01). volatile fatty acid In addition, ratio methanogens bacteria 0.05), reduction notably greater (45.3% vs. 15.2% decrease), although diversity methanogenic archaea not affected either or group. Bioinformatic analysis illustrated that archaeal community predominated by Methanobrevibacter genus (>72.5%), followed Methanomassiliicoccus (>20.9%) Methanosphaera (>1.0%). could play important role presence GSP, though it is usually considered be main hydrogenotrophic methanogen. brief, presented high mitigate decreasing bacteria. GSP. However, relatively low administration level should taken into consideration order obtain inhibitory emission, minimal negative fermentation.