Influence of agroecology practices on rumen microbiota associated with methane emission in dairy cattle

Agroecology is a way to manage agroecosystems through the application of ecological principles. In dairy farming, implementation of agroecology aims to sustainable yet productive farms. A core principle is to incorporate diversity in farm components such as feed and animal. It is unclear, however, whether this diversity modifies the rumen microbiota and its environmentally threatening association with methane emission. The objective of this study was to decipher how the increase of botanical diversity in silage and late mowing of grasslands to produce silage, another principle of agroecology, modified the rumen microbiota of diverse dairy cattle breeds. Three groups of cows of different breeds, namely Holstein Friesian, Groninger Blaarkop and Jersey, were fed experimental silage-based diets with increasing levels of botanical diversity from late mowed grasslands compared to a reference silage-based diet with low botanical diversity and mowed earlier. Methane intensity was measured individually through GreenFeed stations. Rumen microbiota was characterized through 16S rRNA gene amplicon sequencing.