Two research groups are involved in this sub-line: one is devoted to studies on animal (single-stomached) nutrition, and the other to human nutrition. Work is firstly focused on nutrient and energy utilization, and to identify specific events and compounds involved in the metabolic response to food intake. In farm animal studies, attention is chiefly paid to pigs and poultry, and particularly to local breeds. The main task is the assessment of their balanced nutrition within sustainable, environmentally friendly animal production systems. Some specific objectives are: 1) defining animal nutrient and energy requirements for specific physiological functions; 2) evaluation of feed resources; 3) contributing to the development of experimental models to examine nutrition-health interactions in humans. The study of the mechanisms of action and biological effects in productive (swine, poultry) and laboratory (rat) animals and in humans of bioactive substances is the second main topic within this sub-line. Some specific problems addressed are: 1) to determine the nutritional value of chemically well defined, purified fractions (proteins, carbohydrates, lipids) from feed- or foodstuffs; 2) the local (intestine) and/or systemic mechanisms of action of purified compounds such as protease inhibitors, Maillard reaction products, prebiotics, etc.; 3) the potential usefulness of dietary compounds as functional feed or food ingredients on gut microbiota, protein and lipid metabolism, cholesterolemia, oxidative stress, etc. together with the mechanisms involved.