Principles of basic animal nutrition and feeding subjects chemical composition, nutritive value, intake, digestion, absorption, utilization, gastrointestinal functionality of feeds in animal nutrition and health. In the last decades, precision animal nutrition is the new trend which combines and balance highly diversified feed constitutes such as probiotics, prebiotics, synbiotics, smino acids, protein hydrolysates, lipids, enzymes, vitamins, trace elements, clay minerals, dietary fibers, nonstarch polysaccharides, essential oils, herbs, spices and their extracts, saponins, condensed tannins, phytogenic feed additives, butyrate and many others. Apart from nutrition, some new approaches are tied to animal nutrition in relation to mycotoxins, antibiotics, oxidant/antioxidant balance, genetically modified feeds, deficiency and excess of minerals, nano mineral elements and many others. Sector is in a fast progress. Here some different approaches are presented in this book.