To improve feed resource efficiency and to reduce the environmental impact of dairy farming, improving feed efficiency has gained increasing interest. Feed efficiency has shown to be a heritable trait and is currently included in the breeding objective. Research suggests that (part of) the variation between cows in feed efficiency could be explained by differences in digestibility between cows. However, inter-individual variation in feed digestibility measured at large cohorts of animals is lacking and limited knowledge is available on the relation between feed intake, feed intake pattern, feed digestibility and feed efficiency. Hence, in close collaboration with the Animal Breeding and Genomics group, the aim is to get insight into the (genetic) variation in feed digestibility (e.g. fibre and nitrogen) and feed efficiency by collecting and analysing faecal samples of approximately 400 cows from which individual feed intake is recorded. Furthermore, fast and effective methods to estimate digestibility and feed efficiency via spectroscopy measurements will be explored.