ABSTRACT
This chapter highlights key aspects of Amino Acid (AA) nutrition and metabolism in animals. The protein digestion products are absorbed into the enterocytes via AA and peptide transporters. Among the different segments of the small intestine, the jejunum is the major site for terminal protein digestion and the absorption of the digestion products, but these processes also take place in the duodenum and ileum. The biochemical processes of nitrogen metabolism in the large intestine are similar to those in the rumen of ruminants, but the hindgut fermentation of dietary protein in nonruminants is much less effective than rumen fermentation. Optimizing AA nutrition through dietary supplementation with high-quality protein or AAs is an efficient and feasible way to enhance the yields and efficiency of livestock, poultry, and fish production, while ensuring the optimal health of animals and reducing the generation of animal wastes on farms.
