ABSTRACT. The SMARTER (SMAll RuminanT breeding for Efficiency and Resilience) H2020 project aims to develop and implement innovative strategies to improve resilience and efficiency (RandE) related traits in sheep and goats. Regarding feed efficiency, the objective is to identify novel traits that would be relevant, easy to measure and cheap enough to be collected in many animals to identify the most efficient individuals. In practice, feed efficiency can be assessed by different criteria such as residual feed intake and feed conversion ratio. Both criteria require feed intake to be measured for each individual which remains an expensive trait to get and hardly feasible under farm conditions. Thus, our objective is to identify novel traits related to feed efficiency and use them as proxies for feed intake and/or feed efficiency.