Animalia typically have a digestive tract for digestion of food and absorption of water. The intestinal tract is a nutrient-rich environment, as the digestive system of the host often lacks enzymes necessary to degrade certain food components. Other sources of nutrients originate from the high turnover of epithelial cells covering the intestinal surface and from the production of mucus. As the lining of the intestine is continuous with the skin, the interior intestinal space (chyme) of the intestine is external environment. There, as a consequence, is a continuous contamination pressure by bacteria that during evolution proved to be useful for further metabolism of nutrients, which the host failed to utilize. Intestinal flora coevolved with its host and the selection was driven by the intestinal architecture (morphology and transit scheme) and dietary habits of the host. Different animal species have different typical profiles of intestinal bacterial populations. The pertinently existing inter-individual differences between members of certain species are a variation on this typical profile. Animals in general seem not to be able to hydrolyze beta-glycoside bonds, such as the chicory inulin beta(2-1) bond. Chicory fructans were shown to be prebiotic (selectively interacting with intestinal bacterial ecosystem) (1) in humans and in animals, including livestock and pets. This article describes how prebiotic feeding contributes to zootechnical performance of livestock (pig, calf, horse, broiler, laying hen, and fish), which is driven by intestinal functioning, and to animal well-being (mainly pets but also livestock,) which has intestinal but also derived systemic origins.