The digestive health covers all the parameters enabling the animal to maintain its intestinal equilibrium, in response to various factors such nutrients intake or exogenous microorganisms. If the digestive balance is not maintained, troubles could appear such as diarrhoea in the young animal, either because of gut colonisation by an identified pathogen (e.g. E. Coli) or from a multifactorial origin. However, within a group, animals differently develop the clinical symptoms (diarrhoea, impaction) and not all the sick animals die. Several mechanisms of defence could explain the variability in the disease sensibility such as: the gut barrier function, the competitive exclusion between saprophyte and pathogen bacteria and the immune status. Nutrition and feeding strategies also play an important role in digestive health, in supplying the adequate nutrients quantity and quality, to improve: i) mucosa integrity and immune response (avoiding pathogen attachment and colonisation) ii) the growth/stability of the commensal microbiota (barrier effect).