Study shows proanthocyanidins reduce enteric methane in dairy cows via MCR inhibition and microbiome shifts (microbiomejournal.biomedcentral.com)

• PAC reduced methane by 22% in vitro and ~8% in vivo
• PAC improved nitrogen utilization without affecting milk yield
• Metagenomics showed increased Bacteroidota and decreased methanogenesis genes
• Untargeted metabolomics revealed metabolite shifts
• Study suggests PAC as natural methane mitigation strategy

"A study in Microbiome found that proanthocyanidins (PAC) reduce methane emissions in lactating dairy cows by interacting with methyl-coenzyme M reductase (MCR) and altering the rumen microbiome. Computational screening of 3,900 phytochemicals identified PAC as top candidate. In vitro, PAC reduced methane by 22% and increased dry matter degradability. In vivo, dietary PAC (10 or 20 g/kg DM) decreased daily methane by ~8% and improved nitrogen utilization without affecting milk yield. Amplicon sequencing and metagenomics revealed increased Bacteroidota and decreased methanogenesis genes. Untargeted metabolomics showed shifts in metabolite profiles. The study suggests PAC as a natural methane mitigation strategy."