Modulation of milking performance, methane emissions, and rumen microbiome on dairy cows by dietary supplementation of a blend of essential oils

[…] The results from this study indicate that feeding 1 g/d of a blend of essential oils containing eugenol, geranyl acetate, and coriander reduces methane emissions either on absolute terms or expressed per kilogram of feed consumed with no consequences on milk production or composition. However, feed efficiency is slightly reduced. These changes are likely induced by shifts in the rumen microbial population, which experienced an increase in relative abundances of Entodonium and a decrease in relative abundances of Fusobacteria, Chytridiomycota, Epidinium, and Mogibacterium when cows are supplemented with the blend of essential oils used herein.