Resveratrol affects in vitro rumen fermentation, methane production and prokaryotic community composition in a time‐ and diet‐specific manner

Summary This study aimed to investigate the effect of resveratrol on methane production, rumen fermentation and microbial composition under high‐concentrate (HC) and high‐forage (HF) diets using the in vitro fermentation system. A total of 25 mg of resveratrol was supplemented into 300 mg of either HC or HF diet. Methane production, total volatile fatty acid (VFA) concentration, molar proportion of VFA, metabolites of resveratrol and prokaryotic community composition were measured after 12 and 24 h of in vitro fermentation. Resveratrol reduced methane production (ml per mg of dry matter degraded) by 41% and 60% under both HC and HF diets (P