The combustion calorimeter available on the platform is an automatic combustion calorimeter with three operating modes (Adiabatic, Isoperibolic and Dynamic). This device makes it possible (i) to measure the energy contained in food and in the various biological materials; (ii) to evaluate the energy assimilated at different stages of nutrition and (iii) to establish a correlation between the energy expenditure (measured by indirect calorimetry) and the physiological functions of the animals. The assimilated energy is calculated by the difference between the total calories ingested and excreted in the faeces. It expresses dietary efficiency, which is particularly informative to value the contribution of intestinal absorption and nutriments digestibility in energy metabolism of metabolic diseases (diabetes, obesity, ...) and inflammatory bowel diseases (IBD) with evident alteration or adaptation of the overall energy balance.