The research focusses on the feed characteristics and on animal properties which influence intake and subsequent processes in the animal. Processes in the gastro-intestinal tract are studied with regard to the kinetics in its various parts. Subsequently, also utilisation of nutrients absorbed from the feed is studied in relation to development en production of animals. The aim is to optimize nutrition for the production of products for human consumption. On the other hand, the animal functioning with regard to its health and the environmental impact of animal production is very important. Models are being developed to stimulate gastro-intestinal functioning using data from kinetics. Modelling techniques are also used to study development in other animals (calves, poultry) using nutrients absorbed from gastro-intestinal tract. In recent years, more focus is on the studies on gut health in relation to fermentative properties of feed components. Especially gut ecology will receive more attention inthe near future. Effects of nutrition on emission of waste to the environment have specific attention. As a follow-up on studies about the impact of technological treatment on elimination of anti-nutritional factors the origin of endogenous protein production is studied. In that respect also the physico-chemical properties of feed after technological treatment are evaluated with regard to physical properties and there impact on digestion.