Due to the feed materials and animal digestion system, 20% of the protein in poultry feed can't be digested and used by the birds. This is why protein enzymes are introduced to the feed. Enzymes are biological catalysts that aid in the breakdown of feed nutrients and improve digestion of dietary components. The use of exogenous feed enzymes in poultry diet is becoming a norm to overcome the adverse effects of anti-nutritional factors and improve bird performance. Protease is a protein-digesting enzyme that breaks down storage proteins binding starch within feed ingredients, making the energy from protein-bound starch available to the bird for productive purposes. Other enzymes such as xylanases, amylases, and beta-glucanase aid in the digestion of fibrous animal feedstuffs.