Enzymes in broiler diets with special reference to protease

Enzyme supplementation of poultry diets is nutritionally, economically and environmentally justified. Enzymes are used to increase the energy value of feed ingredients and enhance the utilisation of protein, fats, carbohydrates and phytin phosphorus from plant materials, leading to a lower excretion rate of undigested nutrients into the environment and, hence, reduced environmental pollution. This is especially important regarding proteases, as the correct digestion of nitrogenous compounds in feed materials is essential for reducing N excretion - a major pollutant worldwide. Numerous studies have shown no adverse effects of enzyme supplementation in broiler diets on body weight, mortality, health, feed intake, FCR, nutrient digestibility, meat quality and production costs. However, there is still a large amount of uncertainty regarding the use of enzymes.