The influence of microbiomes on their hosts has emerged as one of the most promising factors able to modulate and improve livestock phenotypes, especially health and feed efficiency. Furthermore, increasing evidence is showing an involvement of microbiota into the gut-brain axis, which might contribute to individual welfare. Host-microbiota interactions are influenced by a myriad of external factors, from environment and diets to general management practices, but also by host genetics. The H2020 SFS-02-2020 project call targets these topics by asking for research on the interplay between the production animals and their microbial ecosystems in order to contribute to the improvement of sustainable livestock production. The aim of these ANR MRSEI project is to construct a network and provide a framework allowing the construction of a strong consortium for answering to the SFS-02-2020 project call. The project will contribute to the construction of the project consortium by funding three physical meetings of the whole consortium.