The research scope is the development of new technologies that can promote the green transition of agriculture and the development of a more sustainable livestock production with a key interest in inter-disciplinarily, i.e. the interplay between feed production, nutrition, rumen microbiome, genetics, and product quality. The research area covers ruminant production with emphasis on improved utilisation of nutrients in dairy cows and reduced environmental impact of cattle production in general. More specifically feed additives and feeding strategies that can facilitate significant reductions in enteric methane. This information is used to model the effect of different interventions on production of enteric methane and N-utilization.